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Ganguly S, Chattopadhyay T, Kazi R, Das S, Malik B, Ml U, Iyer PS, Kashiv M, Singh A, Ghadge A, Nair SD, Sonawane MS, Kolthur-Seetharam U. Consumption of sucrose-water rewires macronutrient uptake and utilization mechanisms in a tissue specific manner. J Nutr Biochem 2025; 139:109850. [PMID: 39889860 DOI: 10.1016/j.jnutbio.2025.109850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Revised: 10/31/2024] [Accepted: 01/25/2025] [Indexed: 02/03/2025]
Abstract
Consumption of sugar-sweetened beverages (SSBs) have been linked to metabolic dysfunction, obesity, diabetes and enhanced risk of cardiovascular diseases across all age-groups globally. Decades of work that have provided insights into pathophysiological manifestations of sucrose overfeeding have employed paradigms that rarely mimic human consumption of SSBs. Thus, our understanding of multiorgan cross-talk and molecular and/or cellular mechanisms, which operate across scales and drive physiological derangement is still poor. By employing a paradigm of sucrose water feeding in mice that closely resembles chronic SSB consumption in humans (10% sucrose in water), we have unraveled hitherto unknown tissue-specific mechanistic underpinnings, which contribute towards perturbed physiology. Our findings illustrate that systemic impaired glucose homeostasis, mediated by hepatic gluconeogenesis and insulin resistance, does not involve altered gene expression programs in the liver. We have discovered the pivotal role of the small intestine, which in conjunction with liver and muscles, drives dyshomeostasis. Importantly, we have uncovered rewiring of molecular mechanisms in the proximal intestine that is either causal or consequential to systemic ill-effects of chronic sucrose water consumption including dysfunction of liver and muscle mitochondria. Tissue-specific molecular signatures, which we have unveiled as the primary outcome, clearly indicate that inefficient utilization of glucose is exacerbated by enhanced uptake by the gut. Besides providing systems-wide mechanistic insights, we propose that consumption of SSBs causes intestinal 'molecular addiction' for deregulated absorption of hexose-sugars, and drives diseases such as diabetes and obesity.
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Affiliation(s)
- Saptarnab Ganguly
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India
| | - Tandrika Chattopadhyay
- Centre for innovation in molecular and pharmaceutical sciences, Dr. Reddy's Institute of Life Sciences, Hyderabad, Telangana, India
| | - Rubina Kazi
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Souparno Das
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Bhavisha Malik
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Uthpala Ml
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India
| | - Padmapriya S Iyer
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India
| | - Mohit Kashiv
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India
| | - Anshit Singh
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Amita Ghadge
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India
| | - Shyam D Nair
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India
| | - Mahendra S Sonawane
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India; Development and Aging (ARUMDA), Advanced Research Unit on Metabolism, Tata Institute of Fundamental Research, Hyderabad, Telangana, India.
| | - Ullas Kolthur-Seetharam
- Tata Institute of Fundamental Research, Subject Board of Biology, Hyderabad, Telangana, India; Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India; Development and Aging (ARUMDA), Advanced Research Unit on Metabolism, Tata Institute of Fundamental Research, Hyderabad, Telangana, India; Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, India.
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Štancl P, Gršković P, Držaić S, Vičić A, Karlić R, Korać P. RNA-Sequencing Identification of Genes Supporting HepG2 as a Model Cell Line for Hepatocellular Carcinoma or Hepatocytes. Genes (Basel) 2024; 15:1460. [PMID: 39596661 PMCID: PMC11593409 DOI: 10.3390/genes15111460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2024] [Revised: 10/31/2024] [Accepted: 11/06/2024] [Indexed: 11/29/2024] Open
Abstract
Background/Objectives: Cell lines do not faithfully replicate the authentic transcriptomic condition of the disease under study. The HepG2 cell line is widely used for studying hepatocellular carcinoma (HCC), but not all biological processes and genes exhibit congruent expression patterns between cell lines and the actual disease. The objective of this study is to perform a comparative transcriptomic analysis of the HepG2 cell line, HCC, and primary hepatocytes (PH) in order to identify genes suitable for research in HepG2 as a model for PH or HCC research. Methods: We conducted a differential expression analysis between publicly available data from HCC patients, PH, and HepG2. We examined specific overlaps of differentially expressed genes (DEGs) in a pairwise manner between groups in order to obtain a valuable gene list for studying HCC or PH using different parameter filtering. We looked into the function and druggability of these genes. Conclusions: In total, we identified 397 genes for HepG2 as a valuable HCC model and 421 genes for HepG2 as a valuable PH model, and with more stringent criteria, we derived a smaller list of 40 and 21 genes, respectively. The majority of genes identified as a valuable set for the HCC model are involved in DNA repair and protein degradation mechanisms. This research aims to provide detailed guidance on gene selection for studying diseases like hepatocellular carcinoma, primary hepatocytes, or others using cell lines.
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Affiliation(s)
- Paula Štancl
- Bioinformatics Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (P.Š.); (S.D.)
| | - Paula Gršković
- Biomedical Research Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia;
| | - Sara Držaić
- Bioinformatics Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (P.Š.); (S.D.)
| | - Ana Vičić
- Department of Obstetrics and Gynecology, Clinical Hospital “Sveti Duh”, 10000 Zagreb, Croatia;
| | - Rosa Karlić
- Bioinformatics Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (P.Š.); (S.D.)
| | - Petra Korać
- Biomedical Research Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia;
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Hernandez A, Belfleur L, Migaud M, Gassman NR. A tipping point in dihydroxyacetone exposure: mitochondrial stress and metabolic reprogramming alter survival in rat cardiomyocytes H9c2 cells. Chem Biol Interact 2024; 394:110991. [PMID: 38582340 PMCID: PMC11069339 DOI: 10.1016/j.cbi.2024.110991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 03/20/2024] [Accepted: 04/02/2024] [Indexed: 04/08/2024]
Abstract
Exogenous exposures to the triose sugar dihydroxyacetone (DHA) occur from sunless tanning products and electronic cigarette aerosol. Once inhaled or absorbed, DHA enters cells, is converted to dihydroxyacetone phosphate (DHAP), and incorporated into several metabolic pathways. Cytotoxic effects of DHA vary across the cell types depending on the metabolic needs of the cells, and differences in the generation of reactive oxygen species (ROS), cell cycle arrest, and mitochondrial dysfunction have been reported. We have shown that cytotoxic doses of DHA induced metabolic imbalances in glycolysis and oxidative phosphorylation in liver and kidney cell models. Here, we examine the dose-dependent effects of DHA on the rat cardiomyocyte cell line, H9c2. Cells begin to experience cytotoxic effects at low millimolar doses, but an increase in cell survival was observed at 2 mM DHA. We confirmed that 2 mM DHA increased cell survival compared to the low cytotoxic 1 mM dose and investigated the metabolic differences between these two low DHA doses. Exposure to 1 mM DHA showed changes in the cell's fuel utilization, mitochondrial reactive oxygen species (ROS), and transient changes in the glycolysis and mitochondrial energetics, which normalized 24 h after exposure. The 2 mM dose induced robust changes in mitochondrial flux through acetyl CoA and elevated expression of fatty acid synthase. Distinct from the 1 mM dose, the 2 mM exposure increased mitochondrial ROS and NAD(P)H levels, and sustained changes in LDHA/LDHB and acetyl CoA-associated enzymes were observed. Although the cells were exposed to low cytotoxic (1 mM) and non-cytotoxic (2 mM) acute doses of DHA, significant changes in mitochondrial metabolic pathways occurred. Further, the proliferation increase at the acute 2 mM DHA dose suggests a metabolic adaption occurred with sustained consequences in survival and proliferation. With increased exogenous exposure to DHA through e-cigarette aerosol, this work suggests cell metabolic changes induced by acute or potentially chronic exposures could impact cell function and survival.
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Affiliation(s)
- Arlet Hernandez
- Department of Pharmacology and Toxicology, The University of Alabama at Birmingham, 1720 2nd Ave S, Birmingham, AL, 35294, USA
| | - Luxene Belfleur
- Department of Pharmacology, Whiddon College of Medicine, University of South Alabama, 1660 Springhill Ave, Mobile, AL, 36604, USA
| | - Marie Migaud
- Department of Pharmacology, Whiddon College of Medicine, University of South Alabama, 1660 Springhill Ave, Mobile, AL, 36604, USA
| | - Natalie R Gassman
- Department of Pharmacology and Toxicology, The University of Alabama at Birmingham, 1720 2nd Ave S, Birmingham, AL, 35294, USA.
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Kopec M, Beton-Mysur K. The role of glucose and fructose on lipid droplet metabolism in human normal bronchial and cancer lung cells by Raman spectroscopy. Chem Phys Lipids 2024; 259:105375. [PMID: 38159659 DOI: 10.1016/j.chemphyslip.2023.105375] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/18/2023] [Accepted: 12/27/2023] [Indexed: 01/03/2024]
Abstract
Fructose is one of the most important monosaccharides in the human diet that the human body needs for proper metabolism. This paper presents an approach to study biochemical changes caused by sugars in human normal bronchial cells (BEpiC) and human cancer lung cells (A549) by Raman spectroscopy and Raman imaging. Results after supplementation of human bronchial and lung cells with fructose are also discussed and compared with results obtained for pure human bronchial and lung cells. Based on Raman techniques we have proved that peaks at 750 cm-1, 1126 cm-1, 1444 cm-1, 1584 cm-1 and 2845 cm-1 can be treated as biomarkers to monitor fructose changes in cells. Results for fructose have been compared with results for glucose. Raman analysis of the bands at 750 cm-1, 1126 cm-1, 1584 cm-1 and 2845 cm-1 for pure BEpiC and A549 cells and BEpiC and A549 after supplementation with fructose and glucose are higher after supplementation with fructose in comparison to glucose. The obtained results shed light on the uninvestigated influence of glucose and fructose on lipid droplet metabolism by Raman spectroscopy methods.
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Affiliation(s)
- Monika Kopec
- Lodz University of Technology, Institute of Applied Radiation Chemistry, Laboratory of Laser Molecular Spectroscopy, Wroblewskiego 15, 93-590 Lodz, Poland.
| | - Karolina Beton-Mysur
- Lodz University of Technology, Institute of Applied Radiation Chemistry, Laboratory of Laser Molecular Spectroscopy, Wroblewskiego 15, 93-590 Lodz, Poland
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Weiner J, Dommel S, Gebhardt C, Hanschkow M, Popkova Y, Krause K, Klöting N, Blüher M, Schiller J, Heiker JT. Differential expression of immunoregulatory cytokines in adipose tissue and liver in response to high fat and high sugar diets in female mice. Front Nutr 2023; 10:1275160. [PMID: 38024380 PMCID: PMC10655005 DOI: 10.3389/fnut.2023.1275160] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
A comprehensive understanding of how dietary components impact immunoregulatory gene expression in adipose tissue (AT) and liver, and their respective contributions to metabolic health in mice, remains limited. The current study aimed to investigate the metabolic consequences of a high-sucrose diet (HSD) and a high-fat diet (HFD) in female mice with a focus on differential lipid- and sucrose-induced changes in immunoregulatory gene expression in AT and liver. Female C57BL/6 J mice were fed a purified and macronutrient matched high fat, high sugar, or control diets for 12 weeks. Mice were extensively phenotyped, including glucose and insulin tolerance tests, adipose and liver gene and protein expression analysis by qPCR and Western blot, tissue lipid analyses, as well as histological analyses. Compared to the control diet, HSD- and HFD-fed mice had significantly higher body weights, with pronounced obesity along with glucose intolerance and insulin resistance only in HFD-fed mice. HSD-fed mice exhibited an intermediate phenotype, with mild metabolic deterioration at the end of the study. AT lipid composition was significantly altered by both diets, and inflammatory gene expression was only significantly induced in HFD-fed mice. In the liver however, histological analysis revealed that both HSD- and HFD-fed mice had pronounced ectopic lipid deposition indicating hepatic steatosis, but more pronounced in HSD-fed mice. This was in line with significant induction of pro-inflammatory gene expression specifically in livers of HSD-fed mice. Overall, our findings suggest that HFD consumption in female mice induces more profound inflammation in AT with pronounced deterioration of metabolic health, whereas HSD induced more pronounced hepatic steatosis and inflammation without yet affecting glucose metabolism.
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Affiliation(s)
- Juliane Weiner
- Medical Department III - Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
| | - Sebastian Dommel
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Claudia Gebhardt
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Martha Hanschkow
- Institute for Medical Physics and Biophysics, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Yulia Popkova
- Institute for Medical Physics and Biophysics, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Kerstin Krause
- Medical Department III - Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
- Deutsches Zentrum für Diabetesforschung e.V., Neuherberg, Germany
| | - Nora Klöting
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Matthias Blüher
- Medical Department III - Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Jürgen Schiller
- Institute for Medical Physics and Biophysics, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - John T. Heiker
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
- Institute for Biochemistry, Faculty of Life Sciences, University of Leipzig, Leipzig, Germany
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Ondee T, Pongpirul K, Udompornpitak K, Sukkummee W, Lertmongkolaksorn T, Senaprom S, Leelahavanichkul A. High Fructose Causes More Prominent Liver Steatohepatitis with Leaky Gut Similar to High Glucose Administration in Mice and Attenuation by Lactiplantibacillus plantarum dfa1. Nutrients 2023; 15:1462. [PMID: 36986190 PMCID: PMC10056651 DOI: 10.3390/nu15061462] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/02/2023] [Accepted: 03/07/2023] [Indexed: 03/30/2023] Open
Abstract
High-sugar diet-induced prediabetes and obesity are a global current problem that can be the result of glucose or fructose. However, a head-to-head comparison between both sugars on health impact is still lacking, and Lactiplantibacillus plantarum dfa1 has never been tested, and has recently been isolated from healthy volunteers. The mice were administered with the high glucose or fructose preparation in standard mouse chaw with or without L. plantarum dfa1 gavage, on alternate days, and in vitro experiments were performed using enterocyte cell lines (Caco2) and hepatocytes (HepG2). After 12 weeks of experiments, both glucose and fructose induced a similar severity of obesity (weight gain, lipid profiles, and fat deposition at several sites) and prediabetes condition (fasting glucose, insulin, oral glucose tolerance test, and Homeostatic Model Assessment for Insulin Resistance (HOMA score)). However, fructose administration induced more severe liver damage (serum alanine transaminase, liver weight, histology score, fat components, and oxidative stress) than the glucose group, while glucose caused more prominent intestinal permeability damage (FITC-dextran assay) and serum cytokines (TNF-α, IL-6, and IL-10) compared to the fructose group. Interestingly, all of these parameters were attenuated by L. plantarum dfa1 administration. Because there was a subtle change in the analysis of the fecal microbiome of mice with glucose or fructose administration compared to control mice, the probiotics altered only some microbiome parameters (Chao1 and Lactobacilli abundance). For in vitro experiments, glucose induced more damage to high-dose lipopolysaccharide (LPS) (1 µg/mL) to enterocytes (Caco2 cell) than fructose, as indicated by transepithelial electrical resistance (TEER), supernatant cytokines (TNF-α and IL-8), and glycolysis capacity (by extracellular flux analysis). Meanwhile, both glucose and fructose similarly facilitated LPS injury in hepatocytes (HepG2 cell) as evaluated by supernatant cytokines (TNF-α, IL-6, and IL-10) and extracellular flux analysis. In conclusion, glucose possibly induced a more severe intestinal injury (perhaps due to LPS-glucose synergy) and fructose caused a more prominent liver injury (possibly due to liver fructose metabolism), despite a similar effect on obesity and prediabetes. Prevention of obesity and prediabetes with probiotics was encouraged.
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Affiliation(s)
- Thunnicha Ondee
- Department of Preventive and Social Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Krit Pongpirul
- Department of Preventive and Social Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
- School of Global Health, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Clinical Research Center, Bumrungrad International Hospital, Bangkok 10110, Thailand
- Department of Infection Biology & Microbiomes, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 3GB, UK
| | - Kanyarat Udompornpitak
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Warumphon Sukkummee
- Center of Excellence in Clinical Pharmacokinetics and Pharmacogenomics, Department of Pharmacology, Faculty of Medicine Chulalongkorn University, Bangkok 10330, Thailand
| | - Thanapat Lertmongkolaksorn
- Research Management and Development Division, Office of the President, Mahidol University, Nakhon Pathom 73170, Thailand
| | - Sayamon Senaprom
- Department of Preventive and Social Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Asada Leelahavanichkul
- Center of Excellence in Translational Research in Inflammation and Immunology Research Unit (CETRII), Department of Microbiology, Chulalongkorn University, Bangkok 10330, Thailand
- Nephrology Unit, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
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Ma Y, Meng A, Dai Y, Yang H, Huang Y, Liu X, Xian L, Yuan X. Hypoglycemic activity of phenols from Pleioblastus amarus (Keng) shells and its main chemical constituents identificatied using UHPLC-Q-TOF-MS. J Funct Foods 2022. [DOI: 10.1016/j.jff.2022.105261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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ÖZKAN H, KUTLU T, YAKAN A, ÖZSOY ŞY. Molecular, biochemical, and histopathological effects of long-term low and high-percentage fructose consumption on the liver in rats. ANKARA ÜNIVERSITESI VETERINER FAKÜLTESI DERGISI 2022; 69:409-417. [DOI: 10.33988/auvfd.855124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2025]
Abstract
The aim of this study was to investigate the lipogenic and inflammatory effects of low and high percentage fructose solutions in rats. Wistar albino rats were fed with fructose solutions for 10 weeks. The groups were as follows: Cont (Control), F15 (Fructose 15%), F30 (Fructose 30%), and F60 (Fructose 60%). Rats' body weights were measured weekly. Also, lipogenic and inflammatory gene expression levels, biochemical parameters, and histopathological changes in the liver were investigated. After 10 weeks, it was observed that the animals in the F60 were the heaviest, while the animals in the F30 were the lightest. In all experimental groups, triglycerides were significantly higher than those of controls (P<0.05). In F30 and F60, TNFα, IL-6, and IL-1β were upregulated in the liver compared to control (P<0.05). In addition, SREBP-1c, ChREBP, FAS, ACACA, and SCD-1 were upregulated in all fructose feeding groups compared to Cont (P<0.05). The livers of rats in the F30 and F60 groups had degenerative changes and steatosis. The most detrimental effects of fructose were observed in F60. The concentration of fructose was found to be a very important factor for maintaining normal liver physiology at the molecular level.
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Fiorello ML, Treweeke AT, Macfarlane DP, Megson IL. Intermittent exposure of cultured endothelial cells to physiologically relevant fructose concentrations has a profound impact on nitric oxide production and bioenergetics. PLoS One 2022; 17:e0267675. [PMID: 35560114 PMCID: PMC9106152 DOI: 10.1371/journal.pone.0267675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/12/2022] [Indexed: 11/18/2022] Open
Abstract
Hyperglycaemia is known to induce endothelial dysfunction and changes in metabolic function, which could be implicated in diabetes-induced cardiovascular disease. To date, however, little is known about the impact of physiologically relevant concentrations of fructose on endothelial cells. A novel in vitro model was devised to establish the impact of substitution of a small proportion of glucose with an equal concentration (0.1 mM or 1 mM) of fructose on EA.hy926 endothelial cells during periodic carbohydrate “meals” superimposed on a normoglycaemic (5.5 mM) background. Parallel experiments were conducted using meals consisting of normoglycaemic glucose, intermediate glucose (12.5 mM) or profound hyperglycaemia (25 mM), each delivered for 2 h, with and without substituted fructose over 50 h. Outcome measures included nitrite as a surrogate marker of the mediator of healthy endothelial function, nitric oxide (NO), and a range of bioenergetic parameters using a metabolic analyser. Despite its relatively low proportion of carbohydrate load, intermittent fructose induced a substantial reduction (approximately 90%) in NO generation in cells treated with either concentration of fructose. Cell markers of oxidative stress were not altered by this treatment regimen. However, the cells experienced a marked increase in metabolic activity induced by fructose, irrespective of the glucose concentration delivered simultaneously in the “meals”. Indeed, glucose alone failed to induce any metabolic impact in this model. Key metabolic findings were a 2-fold increase in basal oxygen consumption rate and a similar change in extracellular acidification rate–a marker of glycolysis. Non-metabolic oxygen consumption also increased substantially in cells exposed to fructose. There was no difference between results with 0.1 mM fructose and those with 1 mM fructose. Low, physiologically relevant concentrations of fructose, delivered in a pattern that mimics mealtime consumption, had a profound impact on endothelial function and bioenergetics in an in vitro cell model. The results suggest that endothelial cells are exquisitely sensitive to circulating fructose; the potential ensuing dysfunction could have major implications for development of atherosclerotic disease associated with high fructose consumption.
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Affiliation(s)
- Maria Luisa Fiorello
- Division of Biomedical Sciences, University of the Highlands & Islands, Inverness, United Kingdom
| | - Andrew T. Treweeke
- Division of Biomedical Sciences, University of the Highlands & Islands, Inverness, United Kingdom
| | - David P. Macfarlane
- Department of Diabetes, NHS Highland, Raigmore Hospital, Inverness, United Kingdom
| | - Ian L. Megson
- Division of Biomedical Sciences, University of the Highlands & Islands, Inverness, United Kingdom
- * E-mail:
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10
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EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA), Turck D, Bohn T, Castenmiller J, de Henauw S, Hirsch‐Ernst KI, Knutsen HK, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Peláez C, Pentieva K, Siani A, Thies F, Tsabouri S, Adan R, Emmett P, Galli C, Kersting M, Moynihan P, Tappy L, Ciccolallo L, de Sesmaisons‐Lecarré A, Fabiani L, Horvath Z, Martino L, Muñoz Guajardo I, Valtueña Martínez S, Vinceti M. Tolerable upper intake level for dietary sugars. EFSA J 2022; 20:e07074. [PMID: 35251356 PMCID: PMC8884083 DOI: 10.2903/j.efsa.2022.7074] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Following a request from five European Nordic countries, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was tasked to provide scientific advice on a tolerable upper intake level (UL) or a safe level of intake for dietary (total/added/free) sugars based on available data on chronic metabolic diseases, pregnancy-related endpoints and dental caries. Specific sugar types (fructose) and sources of sugars were also addressed. The intake of dietary sugars is a well-established hazard in relation to dental caries in humans. Based on a systematic review of the literature, prospective cohort studies do not support a positive relationship between the intake of dietary sugars, in isocaloric exchange with other macronutrients, and any of the chronic metabolic diseases or pregnancy-related endpoints assessed. Based on randomised control trials on surrogate disease endpoints, there is evidence for a positive and causal relationship between the intake of added/free sugars and risk of some chronic metabolic diseases: The level of certainty is moderate for obesity and dyslipidaemia (> 50-75% probability), low for non-alcoholic fatty liver disease and type 2 diabetes (> 15-50% probability) and very low for hypertension (0-15% probability). Health effects of added vs. free sugars could not be compared. A level of sugars intake at which the risk of dental caries/chronic metabolic diseases is not increased could not be identified over the range of observed intakes, and thus, a UL or a safe level of intake could not be set. Based on available data and related uncertainties, the intake of added and free sugars should be as low as possible in the context of a nutritionally adequate diet. Decreasing the intake of added and free sugars would decrease the intake of total sugars to a similar extent. This opinion can assist EU Member States in setting national goals/recommendations.
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van Laar A, Grootaert C, Van Nieuwerburgh F, Deforce D, Desmet T, Beerens K, Van Camp J. Metabolism and Health Effects of Rare Sugars in a CACO-2/HepG2 Coculture Model. Nutrients 2022; 14:nu14030611. [PMID: 35276968 PMCID: PMC8839664 DOI: 10.3390/nu14030611] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 02/06/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide and is impacted by an unhealthy diet with excessive calories, although the role of sugars in NAFLD etiology remains largely unexplored. Rare sugars are natural sugars with alternative monomers and glycosidic bonds, which have attracted attention as sugar replacers due to developments in enzyme engineering and hence an increased availability. We studied the impact of (rare) sugars on energy production, liver cell physiology and gene expression in human intestinal colorectal adenocarcinoma (Caco-2) cells, hepatoma G2 (HepG2) liver cells and a coculture model with these cells. Fat accumulation was investigated in the presence of an oleic/palmitic acid mixture. Glucose, fructose and galactose, but not mannose, l-arabinose, xylose and ribose enhanced hepatic fat accumulation in a HepG2 monoculture. In the coculture model, there was a non-significant trend (p = 0.08) towards higher (20–55% increased) median fat accumulation with maltose, kojibiose and nigerose. In this coculture model, cellular energy production was increased by glucose, maltose, kojibiose and nigerose, but not by trehalose. Furthermore, glucose, fructose and l-arabinose affected gene expression in a sugar-specific way in coculture HepG2 cells. These findings indicate that sugars provide structure-specific effects on cellular energy production, hepatic fat accumulation and gene expression, suggesting a health potential for trehalose and l-arabinose, as well as a differential impact of sugars beyond the distinction of conventional and rare sugars.
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Affiliation(s)
- Amar van Laar
- Department of Food Technology, Safety & Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (A.v.L.); (C.G.)
| | - Charlotte Grootaert
- Department of Food Technology, Safety & Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (A.v.L.); (C.G.)
| | - Filip Van Nieuwerburgh
- NXTGNT, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; (F.V.N.); (D.D.)
| | - Dieter Deforce
- NXTGNT, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; (F.V.N.); (D.D.)
| | - Tom Desmet
- Centre for Synthetic Biology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (T.D.); (K.B.)
| | - Koen Beerens
- Centre for Synthetic Biology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (T.D.); (K.B.)
| | - John Van Camp
- Department of Food Technology, Safety & Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (A.v.L.); (C.G.)
- Correspondence:
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12
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Chen YS, Gleaton J, Yang Y, Dhayalan B, Phillips NB, Liu Y, Broadwater L, Jarosinski MA, Chatterjee D, Lawrence MC, Hattier T, Michael MD, Weiss MA. Insertion of a synthetic switch into insulin provides metabolite-dependent regulation of hormone-receptor activation. Proc Natl Acad Sci U S A 2021; 118:e2103518118. [PMID: 34290145 PMCID: PMC8325334 DOI: 10.1073/pnas.2103518118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Insulin-signaling requires conformational change: whereas the free hormone and its receptor each adopt autoinhibited conformations, their binding leads to structural reorganization. To test the functional coupling between insulin's "hinge opening" and receptor activation, we inserted an artificial ligand-dependent switch into the insulin molecule. Ligand-binding disrupts an internal tether designed to stabilize the hormone's native closed and inactive conformation, thereby enabling productive receptor engagement. This scheme exploited a diol sensor (meta-fluoro-phenylboronic acid at GlyA1) and internal diol (3,4-dihydroxybenzoate at LysB28). The sensor recognizes monosaccharides (fructose > glucose). Studies of insulin-signaling in human hepatoma-derived cells (HepG2) demonstrated fructose-dependent receptor autophosphorylation leading to appropriate downstream signaling events, including a specific kinase cascade and metabolic gene regulation (gluconeogenesis and lipogenesis). Addition of glucose (an isomeric ligand with negligible sensor affinity) did not activate the hormone. Similarly, metabolite-regulated signaling was not observed in control studies of 1) an unmodified insulin analog or 2) an analog containing a diol sensor without internal tethering. Although secondary structure (as probed by circular dichroism) was unaffected by ligand-binding, heteronuclear NMR studies revealed subtle local and nonlocal monosaccharide-dependent changes in structure. Insertion of a synthetic switch into insulin has thus demonstrated coupling between hinge-opening and allosteric holoreceptor signaling. In addition to this foundational finding, our results provide proof of principle for design of a mechanism-based metabolite-responsive insulin. In particular, replacement of the present fructose sensor by an analogous glucose sensor may enable translational development of a "smart" insulin analog to mitigate hypoglycemic risk in diabetes therapy.
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Affiliation(s)
- Yen-Shan Chen
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202
| | | | - Yanwu Yang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Balamurugan Dhayalan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Nelson B Phillips
- Department of Biochemistry, Case Western Reserve University, Cleveland, OH 44106
| | - Yule Liu
- Thermalin Inc., Cleveland, OH 44106
| | | | - Mark A Jarosinski
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Deepak Chatterjee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Michael C Lawrence
- Structural Biology Division, WEHI, Parkville, VIC 3052, Australia
- Department of Medical Biology, University of Melbourne, Royal Parade, Parkville, VIC 3050, Australia
| | | | | | - Michael A Weiss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202;
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13
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Annandale M, Daniels LJ, Li X, Neale JPH, Chau AHL, Ambalawanar HA, James SL, Koutsifeli P, Delbridge LMD, Mellor KM. Fructose Metabolism and Cardiac Metabolic Stress. Front Pharmacol 2021; 12:695486. [PMID: 34267663 PMCID: PMC8277231 DOI: 10.3389/fphar.2021.695486] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/07/2021] [Indexed: 11/13/2022] Open
Abstract
Cardiovascular disease is one of the leading causes of mortality in diabetes. High fructose consumption has been linked with the development of diabetes and cardiovascular disease. Serum and cardiac tissue fructose levels are elevated in diabetic patients, and cardiac production of fructose via the intracellular polyol pathway is upregulated. The question of whether direct myocardial fructose exposure and upregulated fructose metabolism have potential to induce cardiac fructose toxicity in metabolic stress settings arises. Unlike tightly-regulated glucose metabolism, fructose bypasses the rate-limiting glycolytic enzyme, phosphofructokinase, and proceeds through glycolysis in an unregulated manner. In vivo rodent studies have shown that high dietary fructose induces cardiac metabolic stress and functional disturbance. In vitro, studies have demonstrated that cardiomyocytes cultured in high fructose exhibit lipid accumulation, inflammation, hypertrophy and low viability. Intracellular fructose mediates post-translational modification of proteins, and this activity provides an important mechanistic pathway for fructose-related cardiomyocyte signaling and functional effect. Additionally, fructose has been shown to provide a fuel source for the stressed myocardium. Elucidating the mechanisms of fructose toxicity in the heart may have important implications for understanding cardiac pathology in metabolic stress settings.
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Affiliation(s)
- M Annandale
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - L J Daniels
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.,Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - X Li
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - J P H Neale
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - A H L Chau
- Department of Physiology, School of Biomedical Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - H A Ambalawanar
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - S L James
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - P Koutsifeli
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - L M D Delbridge
- Department of Physiology, School of Biomedical Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - K M Mellor
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.,Department of Physiology, School of Biomedical Sciences, University of Melbourne, Melbourne, VIC, Australia
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14
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Bian G, Yang J, Elango J, Wu W, Bao B, Bao C. Natural Triterpenoids Isolated from Akebia trifoliata Stem Explants Exert a Hypoglycemic Effect via α-Glucosidase Inhibition and Glucose Uptake Stimulation in Insulin-Resistant HepG2 Cells. Chem Biodivers 2021; 18:e2001030. [PMID: 33779055 DOI: 10.1002/cbdv.202001030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/25/2021] [Indexed: 12/26/2022]
Abstract
The inhibition of α-glucosidase activity is a prospective approach to attenuate postprandial hyperglycemia in the treatment of type 2 diabetes mellitus (T2DM). Herein, the inhibition of α-glucosidase by three compounds T1 -T3 of Akebia trifoliata stem, namely hederagenin (T1 ), 3-epiakebonoic acid (T2 ), and arjunolic acid (T3 ) were investigated using enzyme kinetics and molecular docking analysis. The three triterpenoids exhibited excellent inhibitory activities against α-glucosidase. T1 -T3 showed the strongest inhibition with IC50 values of 42.1±5.4, 19.6±3.2, and 11.2±2.3 μM, respectively, compared to the acarbose positive control (IC50 =106.3±8.2). Enzyme inhibition kinetics showed that triterpenoids T1 -T3 demonstrated competitive, mixed, and noncompetitive-type inhibition against α-glucosidase, respectively. The inhibition constant (Ki ) values were 21.21, 7.70, and 3.18 μM, respectively. Docking analysis determined that the interaction of ligands T1 -T3 and α-glucosidase was mainly forced by hydrogen bonds and hydrophobic interactions, which could result in improved binding to the active site of the target enzyme. The insulin resistant (IR)-HepG2 cell model used in this study (HepG2 cells exposed to 10-7 M insulin for 24 h) and glucose uptake assays showed that compounds T1 -T3 had no cytotoxicity with concentrations ranging from 6.25 to 25 μM and displayed significant stimulation of glucose uptake in IR-HepG2 cells. Thus, triterpenoids T1 -T3 showed dual therapeutic effects of α-glucosidase inhibition and glucose uptake stimulation and could be used as potential medicinal resources to investigate new antidiabetic agents for the prevention or treatment of diabetes.
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Affiliation(s)
- Guoyong Bian
- Department of Marine Bio-Pharmacology, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, P. R. China
| | - Jinbo Yang
- Department of Marine Bio-Pharmacology, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, P. R. China
| | - Jeevithan Elango
- Department of Marine Bio-Pharmacology, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, P. R. China
| | - Wenhui Wu
- Department of Marine Bio-Pharmacology, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, P. R. China.,National R&D Branch Center for Freshwater Aquatic Products Processing Technology, Shanghai, 201306, P. R. China
| | - Bin Bao
- National R&D Branch Center for Freshwater Aquatic Products Processing Technology, Shanghai, 201306, P. R. China
| | - Chunling Bao
- Shanghai Sixth People's Hospital East Campus, Shanghai, 201306, P. R. China
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15
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Piras IS, Gerhard GS, DiStefano JK. Palmitate and Fructose Interact to Induce Human Hepatocytes to Produce Pro-Fibrotic Transcriptional Responses in Hepatic Stellate Cells Exposed to Conditioned Media. Cell Physiol Biochem 2021; 54:1068-1082. [PMID: 33095528 PMCID: PMC8265013 DOI: 10.33594/000000288] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND/AIMS Excessive consumption of dietary fat and sugar is associated with an elevated risk of nonalcoholic fatty liver disease (NAFLD). Hepatocytes exposed to saturated fat or sugar exert effects on nearby hepatic stellate cells (HSCs); however, the mechanisms by which this occurs are poorly understood. We sought to determine whether paracrine effects of hepatocytes exposed to palmitate and fructose produced profibrotic transcriptional responses in HSCs. METHODS We performed expression profiling of mRNA and lncRNA from HSCs treated with conditioned media (CM) from human hepatocytes treated with palmitate (P), fructose (F), or both (PF). RESULTS In HSCs exposed to CM from palmitate-treated hepatocytes, we identified 374 mRNAs and 607 lncRNAs showing significant differential expression (log2 foldchange ≥ |1|; FDR ≤0.05) compared to control cells. In HSCs exposed to CM from PF-treated hepatocytes, the number of differentially expressed genes was much higher (1198 mRNAs and 3348 lncRNAs); however, CM from fructose-treated hepatocytes elicited no significant changes in gene expression. Pathway analysis of differentially expressed genes showed enrichment for hepatic fibrosis and hepatic stellate cell activation in P- (FDR =1.30E-04) and PF-(FDR =9.24E-06)
groups. We observed 71 lncRNA/nearby mRNA pairs showing differential expression under PF conditions. There were 90 mRNAs and 264 lncRNAs strongly correlated between the PF group and differentially expressed transcripts from a comparison of activated and quiescent HSCs, suggesting that some of the transcriptomic changes occurring in response to PF overlap with HSC activation. CONCLUSION The results reported here have implications for dietary modifications in the prevention and treatment of NAFLD.
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Affiliation(s)
| | - Glenn S Gerhard
- Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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16
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Gunn PJ, Pramfalk C, Millar V, Cornfield T, Hutchinson M, Johnson EM, Nagarajan SR, Troncoso‐Rey P, Mithen RF, Pinnick KE, Traka MH, Green CJ, Hodson L. Modifying nutritional substrates induces macrovesicular lipid droplet accumulation and metabolic alterations in a cellular model of hepatic steatosis. Physiol Rep 2020; 8:e14482. [PMID: 32643289 PMCID: PMC7343665 DOI: 10.14814/phy2.14482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/02/2020] [Accepted: 05/18/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND AIMS Nonalcoholic fatty liver disease (NAFLD) begins with steatosis, where a mixed macrovesicular pattern of large and small lipid droplets (LDs) develops. Since in vitro models recapitulating this are limited, the aims of this study were to develop mixed macrovesicular steatosis in immortalized hepatocytes and investigate effects on intracellular metabolism by altering nutritional substrates. METHODS Huh7 cells were cultured in 11 mM glucose and 2% human serum (HS) for 7 days before additional sugars and fatty acids (FAs), either with 200 µM FAs (low fat low sugar; LFLS), 5.5 mM fructose + 200 µM FAs (low fat high sugar; LFHS), or 5.5 mM fructose + 800 µM FAs (high fat high sugar; HFHS), were added for 7 days. FA metabolism, lipid droplet characteristics, and transcriptomic signatures were investigated. RESULTS Between the LFLS and LFHS conditions, there were few notable differences. In the HFHS condition, intracellular triacylglycerol (TAG) was increased and the LD pattern and distribution was similar to that found in primary steatotic hepatocytes. HFHS-treated cells had lower levels of de novo-derived FAs and secreted larger, TAG-rich lipoprotein particles. RNA sequencing and gene set enrichment analysis showed changes in several pathways including those involved in metabolism and cell cycle. CONCLUSIONS Repeated doses of HFHS treatment resulted in a cellular model of NAFLD with a mixed macrovesicular LD pattern and metabolic dysfunction. Since these nutrients have been implicated in the development of NAFLD in humans, the model provides a good physiological basis for studying NAFLD development or regression in vitro.
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Affiliation(s)
- Pippa J. Gunn
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Camilla Pramfalk
- Division of Clinical ChemistryDepartment of Laboratory MedicineKarolinska Institutet at Karolinska University Hospital HuddingeStockholmSweden
| | - Val Millar
- Target Discovery InstituteNuffield Department of MedicineUniversity of OxfordOxfordUK
| | - Thomas Cornfield
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Matthew Hutchinson
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Elspeth M. Johnson
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Shilpa R. Nagarajan
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | | | | | - Katherine E. Pinnick
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | | | - Charlotte J. Green
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and MetabolismRadcliffe Department of MedicineUniversity of OxfordOxfordUK
- National Institute for Health Research Oxford Biomedical Research CentreOxford University Hospital TrustsOxfordUK
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17
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Al-Jawadi A, Patel CR, Shiarella RJ, Romelus E, Auvinen M, Guardia J, Pearce SC, Kishida K, Yu S, Gao N, Ferraris RP. Cell-Type-Specific, Ketohexokinase-Dependent Induction by Fructose of Lipogenic Gene Expression in Mouse Small Intestine. J Nutr 2020; 150:1722-1730. [PMID: 32386219 PMCID: PMC7330472 DOI: 10.1093/jn/nxaa113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/06/2020] [Accepted: 04/01/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND High intakes of fructose are associated with metabolic diseases, including hypertriglyceridemia and intestinal tumor growth. Although small intestinal epithelia consist of many different cell types, express lipogenic genes, and convert dietary fructose to fatty acids, there is no information on the identity of the cell type(s) mediating this conversion and on the effects of fructose on lipogenic gene expression. OBJECTIVES We hypothesized that fructose regulates the intestinal expression of genes involved in lipid and apolipoprotein synthesis, that regulation depends on the fructose transporter solute carrier family 2 member a5 [Slc2a5 (glucose transporter 5)] and on ketohexokinase (Khk), and that regulation occurs only in enterocytes. METHODS We compared lipogenic gene expression among different organs from wild-type adult male C57BL mice consuming a standard vivarium nonpurified diet. We then gavaged twice daily for 2.5 d fructose or glucose solutions (15%, 0.3 mL per mouse) into wild-type, Slc2a5-knockout (KO), and Khk-KO mice with free access to the nonpurified diet and determined expression of representative lipogenic genes. Finally, from mice fed the nonpurified diet, we made organoids highly enriched in enterocyte, goblet, Paneth, or stem cells and then incubated them overnight in 10 mM fructose or glucose. RESULTS Most lipogenic genes were significantly expressed in the intestine relative to the kidney, liver, lung, and skeletal muscle. In vivo expression of Srebf1, Acaca, Fasn, Scd1, Dgat1, Gk, Apoa4, and Apob mRNA and of Scd1 protein increased (P < 0.05) by 3- to 20-fold in wild-type, but not in Slc2a5-KO and Khk-KO, mice gavaged with fructose. In vitro, Slc2a5- and Khk-dependent, fructose-induced increases, which ranged from 1.5- to 4-fold (P < 0.05), in mRNA concentrations of all these genes were observed only in organoids enriched in enterocytes. CONCLUSIONS Fructose specifically stimulates expression of mouse small intestinal genes for lipid and apolipoprotein synthesis. Secretory and stem cells seem incapable of transport- and metabolism-dependent lipogenesis, occurring only in absorptive enterocytes.
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Affiliation(s)
- Arwa Al-Jawadi
- Present address for AA-J: Thermo Fisher Scientific, 5823 Newton Drive, Carlsbad, CA 92008 USA
| | - Chirag R Patel
- Present address for CRP: Independent Drug Safety Consultant, 1801 Augustine Cut-off, Wilmington, DE 19803
| | - Reilly J Shiarella
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Emmanuellie Romelus
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Madelyn Auvinen
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Joshua Guardia
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Sarah C Pearce
- Present address for SCP: Performance Nutrition Team, Combat Feeding Directorate, Natick Soldier Research, Development, and Engineering Center (NSRDEC), 15 General Greene Avenue, Natick, MA 01760-5018
| | - Kunihiro Kishida
- Present address for KK: Department of Science and Technology on Food Safety, Kindai University, Wakayama 649-6493, Japan
| | - Shiyan Yu
- Department of Biological Sciences, Life Science Center, Rutgers University, Newark, NJ, USA
| | - Nan Gao
- Department of Biological Sciences, Life Science Center, Rutgers University, Newark, NJ, USA
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18
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DiStefano JK. Fructose-mediated effects on gene expression and epigenetic mechanisms associated with NAFLD pathogenesis. Cell Mol Life Sci 2020; 77:2079-2090. [PMID: 31760464 PMCID: PMC7440926 DOI: 10.1007/s00018-019-03390-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a chronic, frequently progressive condition that develops in response to excessive hepatocyte fat accumulation (i.e., steatosis) in the absence of significant alcohol consumption. Liver steatosis develops as a result of imbalanced lipid metabolism, driven largely by increased rates of de novo lipogenesis and hepatic fatty acid uptake and reduced fatty acid oxidation and/or disposal to the circulation. Fructose is a naturally occurring simple sugar, which is most commonly consumed in modern diets in the form of sucrose, a disaccharide comprised of one molecule of fructose covalently bonded with one molecule of glucose. A number of observational and experimental studies have demonstrated detrimental effects of dietary fructose consumption not only on diverse metabolic outcomes such as insulin resistance and obesity, but also on hepatic steatosis and NAFLD-related fibrosis. Despite the compelling evidence that excessive fructose consumption is associated with the presence of NAFLD and may even promote the development and progression of NAFLD to more clinically severe phenotypes, the molecular mechanisms by which fructose elicits effects on dysregulated liver metabolism remain unclear. Emerging data suggest that dietary fructose may directly alter the expression of genes involved in lipid metabolism, including those that increase hepatic fat accumulation or reduce hepatic fat removal. The aim of this review is to summarize the current research supporting a role for dietary fructose intake in the modulation of transcriptomic and epigenetic mechanisms underlying the pathogenesis of NAFLD.
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Affiliation(s)
- Johanna K DiStefano
- Diabetes and Fibrotic Disease Unit, Translational Genomics Research Institute, 445 N 5th Street, Phoenix, AZ, 85004, USA.
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19
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Sakamuri A, Sakamuri SSVP, Kona SR, Jeyapal S, Ibrahim A. Diets with low n-6:n-3 PUFA ratio protects rats from fructose-induced dyslipidemia and associated hepatic changes: Comparison between 18:3 n-3 and long-chain n-3 PUFA. Prostaglandins Leukot Essent Fatty Acids 2020; 155:102082. [PMID: 32169807 DOI: 10.1016/j.plefa.2020.102082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 02/07/2020] [Accepted: 02/18/2020] [Indexed: 12/17/2022]
Abstract
In the present study, we investigated the impact of substituting alpha-linolenic acid (ALA) or long-chain n-3 PUFA (eicosapentaenoic acid and docosahexaenoic acid) for linoleic acid and hence decreasing n-6:n-3 PUFA ratio on high-fructose diet-induced hypertriglyceridemia and associated hepatic changes. Weanling male Wistar rats were divided into four groups and fed with starch-diet (n-6:n-3 PUFA ratio 215:1) and high-fructose diets with different n-6:n-3 PUFA ratio (215:1, 2:1 with ALA and 5:1 with long-chain n-3 PUFA) for twenty-four weeks. Substitution of linoleic acid with ALA (n-6:n-3 PUFA ratio of 2) or long-chain n-3 PUFA (n-6:n-3 PUFA ratio of 5) protected the rats from fructose-induced dyslipidemia, hepatic oxidative stress and corrected lipogenic and proinflammatory gene expression. Both ALA and long-chain n-3 PUFA supplementation also reversed the fructose-induced upregulation of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) gene, which is involved in the generation of active glucocorticoids in tissues. Although both ALA and LC n-3 PUFA prevented fructose-induced dyslipidemia to a similar extent, compared to ALA, LC n-3 PUFA is more effective in preventing hepatic oxidative stress and inflammation.
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Affiliation(s)
- Anil Sakamuri
- Department of lipid chemistry, National Institute of Nutrition, Hyderabad, India
| | - Siva S V P Sakamuri
- Department of lipid chemistry, National Institute of Nutrition, Hyderabad, India
| | - Suryam Reddy Kona
- Department of lipid chemistry, National Institute of Nutrition, Hyderabad, India
| | - Sugeedha Jeyapal
- Department of lipid chemistry, National Institute of Nutrition, Hyderabad, India
| | - Ahamed Ibrahim
- Department of lipid chemistry, National Institute of Nutrition, Hyderabad, India.
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20
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Chen WL, Jin X, Wang M, Liu D, Luo Q, Tian H, Cai L, Meng L, Bi R, Wang L, Xie X, Yu G, Li L, Dong C, Cai Q, Jia W, Wei W, Jia L. GLUT5-mediated fructose utilization drives lung cancer growth by stimulating fatty acid synthesis and AMPK/mTORC1 signaling. JCI Insight 2020; 5:e131596. [PMID: 32051337 PMCID: PMC7098789 DOI: 10.1172/jci.insight.131596] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 01/10/2020] [Indexed: 12/22/2022] Open
Abstract
Lung cancer (LC) is a leading cause of cancer-related deaths worldwide. Its rapid growth requires hyperactive catabolism of principal metabolic fuels. It is unclear whether fructose, an abundant sugar in current diets, is essential for LC. We demonstrated that, under the condition of coexistence of metabolic fuels in the body, fructose was readily used by LC cells in vivo as a glucose alternative via upregulating GLUT5, a major fructose transporter encoded by solute carrier family 2 member 5 (SLC2A5). Metabolomic profiling coupled with isotope tracing demonstrated that incorporated fructose was catabolized to fuel fatty acid synthesis and palmitoleic acid generation in particular to expedite LC growth in vivo. Both in vitro and in vivo supplement of palmitoleic acid could restore impaired LC propagation caused by SLC2A5 deletion. Furthermore, molecular mechanism investigation revealed that GLUT5-mediated fructose utilization was required to suppress AMPK and consequently activate mTORC1 activity to promote LC growth. As such, pharmacological blockade of in vivo fructose utilization using a GLUT5 inhibitor remarkably curtailed LC growth. Together, this study underscores the importance of in vivo fructose utilization mediated by GLUT5 in governing LC growth and highlights a promising strategy to treat LC by targeting GLUT5 to eliminate those fructose-addicted neoplastic cells.
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Affiliation(s)
- Wen-Lian Chen
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xing Jin
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Mingsong Wang
- Department of Thoracic Cardiovascular Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Dan Liu
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Qin Luo
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Hechuan Tian
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lili Cai
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lifei Meng
- Department of Thoracic Cardiovascular Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Rui Bi
- Department of Thoracic Cardiovascular Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Lei Wang
- Department of Thoracic Cardiovascular Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiao Xie
- Department of Thoracic Cardiovascular Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Guanzhen Yu
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lihui Li
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Changsheng Dong
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Qiliang Cai
- Ministry of Education and Ministry of Health Key Lab of Medical Molecular Virology, School of Basic Medical Science, Fudan University, Shanghai, China
| | - Wei Jia
- University of Hawaii Cancer Center, Honolulu, Hawaii, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Lijun Jia
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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21
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Hengist A, Koumanov F, Gonzalez JT. Fructose and metabolic health: governed by hepatic glycogen status? J Physiol 2019; 597:3573-3585. [PMID: 30950506 PMCID: PMC6767689 DOI: 10.1113/jp277767] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 03/20/2019] [Indexed: 12/28/2022] Open
Abstract
Fructose is a commonly ingested dietary sugar which has been implicated in playing a particularly harmful role in the development of metabolic disease. Fructose is primarily metabolised by the liver in humans, and increases rates of hepatic de novo lipogenesis. Fructose increases hepatic de novo lipogenesis via numerous mechanisms: by altering transcriptional and allosteric regulation, interfering with cellular energy sensing, and disrupting the balance between lipid synthesis and lipid oxidation. Hepatic de novo lipogenesis is also upregulated by the inability to synthesise glycogen, either when storage is inhibited in knock‐down animal models or storage is saturated in glycogen storage disease. Considering that fructose has the capacity to upregulate hepatic glycogen storage, and replenish these stores more readily following glycogen depleting exercise, the idea that hepatic glycogen storage and hepatic de novo lipogenesis are linked is an attractive prospect. We propose that hepatic glycogen stores may be a key factor in determining the metabolic responses to fructose ingestion, and saturation of hepatic glycogen stores could exacerbate the negative metabolic effects of excessive fructose intake. Since physical activity potently modulates glycogen metabolism, this provides a rationale for considering nutrient–physical activity interactions in metabolic health.
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22
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Pinnick KE, Hodson L. Challenging metabolic tissues with fructose: tissue-specific and sex-specific responses. J Physiol 2019; 597:3527-3537. [PMID: 30883738 DOI: 10.1113/jp277115] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 02/25/2019] [Indexed: 12/16/2022] Open
Abstract
Excessive consumption of free sugars (which typically includes a composite of glucose and fructose) is associated with an increased risk of developing chronic metabolic diseases including obesity, non-alcoholic fatty liver disease (NAFLD), type 2 diabetes and cardiovascular disease. Determining the utilisation, storage and fate of dietary sugars in metabolically relevant tissues is fundamental to understanding their contribution to metabolic disease risk. To date, the study of fructose metabolism has primarily focused on the liver, where it has been implicated in impaired insulin sensitivity, increased fat accumulation and dyslipidaemia. Yet we still have only a limited understanding of the mechanisms by which consumption of fructose, as part of a mixed meal, may alter hepatic fatty acid synthesis and partitioning. Moreover, surprisingly little is known about the metabolism of fructose within other organs, specifically subcutaneous adipose tissue, which is the largest metabolically active organ in the human body and is consistently exposed to nutrient fluxes. This review summarises what is known about fructose metabolism in the liver and adipose tissue and examines evidence for tissue-specific and sex-specific responses to fructose.
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Affiliation(s)
- Katherine E Pinnick
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
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23
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Lu M, Henry CE, Lai H, Khine YY, Ford CE, Stenzel MH. A new 3D organotypic model of ovarian cancer to help evaluate the antimetastatic activity of RAPTA-C conjugated micelles. Biomater Sci 2019; 7:1652-1660. [DOI: 10.1039/c8bm01326h] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A novel 3D co-culture model of ovarian cancer can be used to test the efficacy of nanomedicine.
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Affiliation(s)
- Mingxia Lu
- Centre for Advanced Macromolecular Design (CAMD)
- School of Chemistry
- University of New South Wales
- Sydney
- Australia
| | - Claire E. Henry
- Gynaecological Cancer Research Group
- Lowy Cancer Research Centre and School of Women's and Children's Health
- Faculty of Medicine
- University of New South Wales
- Sydney
| | - Haiwang Lai
- Centre for Advanced Macromolecular Design (CAMD)
- School of Chemistry
- University of New South Wales
- Sydney
- Australia
| | - Yee Yee Khine
- Centre for Advanced Macromolecular Design (CAMD)
- School of Chemistry
- University of New South Wales
- Sydney
- Australia
| | - Caroline E. Ford
- Gynaecological Cancer Research Group
- Lowy Cancer Research Centre and School of Women's and Children's Health
- Faculty of Medicine
- University of New South Wales
- Sydney
| | - Martina H. Stenzel
- Centre for Advanced Macromolecular Design (CAMD)
- School of Chemistry
- University of New South Wales
- Sydney
- Australia
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24
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Hoang NA, Richter F, Schubert M, Lorkowski S, Klotz LO, Steinbrenner H. Differential capability of metabolic substrates to promote hepatocellular lipid accumulation. Eur J Nutr 2018; 58:3023-3034. [PMID: 30368556 DOI: 10.1007/s00394-018-1847-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 10/23/2018] [Indexed: 02/07/2023]
Abstract
PURPOSE Excessive storage of triacylglycerides (TAGs) in lipid droplets within hepatocytes is a hallmark of non-alcoholic fatty liver disease (NAFLD), one of the most widespread metabolic disorders in Western societies. For the purpose of exploring molecular pathways in NAFLD development and testing potential drug candidates, well-characterised experimental models of ectopic TAG storage in hepatocytes are needed. METHODS Using an optimised Oil Red O assay, immunoblotting and real-time qRT-PCR, we compared the capability of dietary monosaccharides and fatty acids to promote lipid accumulation in HepG2 human hepatoma cells. RESULTS Both high glucose and high fructose resulted in intracellular lipid accumulation after 48 h, and this was further augmented (up to twofold, as compared to basal levels) by co-treatment with the lipogenesis-stimulating hormone insulin and the pro-inflammatory cytokine tumour necrosis factor alpha (TNF-α), respectively. The fatty acids palmitic and oleic acid were even more effective than these carbohydrates, inducing significantly elevated TAG storage already after 24 h of treatment. Highest (about threefold) increases in lipid accumulation were observed upon treatment with oleic acid, alone as well as in combinations with palmitic acid or with high glucose and insulin. Increases in protein levels of a major lipid droplet coat protein, perilipin-2 (PLIN2), mirrored intracellular lipid accumulation following different treatment regimens. CONCLUSIONS Several treatment regimens of excessive fat and sugar supply promoted lipid accumulation in HepG2 cells, albeit with differences in the extent and rapidity of steatogenesis. PLIN2 is a candidate molecular marker of sustained lipid accumulation in HepG2 cells.
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Affiliation(s)
- Ngoc Anh Hoang
- Institute of Nutritional Sciences, Nutrigenomics, Friedrich-Schiller-Universität Jena, Jena, Germany
| | - Friederike Richter
- Institute of Nutritional Sciences, Nutrigenomics, Friedrich-Schiller-Universität Jena, Jena, Germany
| | - Martin Schubert
- Department of Nutritional Biochemistry and Physiology, Institute of Nutritional Sciences, Friedrich-Schiller-Universität Jena, Jena, Germany
- Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD) Halle-Jena-Leipzig, Jena, Germany
| | - Stefan Lorkowski
- Department of Nutritional Biochemistry and Physiology, Institute of Nutritional Sciences, Friedrich-Schiller-Universität Jena, Jena, Germany
- Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD) Halle-Jena-Leipzig, Jena, Germany
| | - Lars-Oliver Klotz
- Institute of Nutritional Sciences, Nutrigenomics, Friedrich-Schiller-Universität Jena, Jena, Germany
| | - Holger Steinbrenner
- Institute of Nutritional Sciences, Nutrigenomics, Friedrich-Schiller-Universität Jena, Jena, Germany.
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25
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The Ability of Different Ketohexoses to Alter Apo-A-I Structure and Function In Vitro and to Induce Hepatosteatosis, Oxidative Stress, and Impaired Plasma Lipid Profile in Hyperlipidemic Zebrafish. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:3124364. [PMID: 29951163 PMCID: PMC5987316 DOI: 10.1155/2018/3124364] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 10/25/2017] [Indexed: 01/22/2023]
Abstract
In the current study, we have tested the nonenzymatic glycation activities of ketohexoses, such as tagatose and psicose. Although tagatose-treated apoA-I (t-A-I) and psicose-treated apoA-I (p-A-I) exerted more inhibitory activity you cupric ion-mediated low-density lipoprotein (LDL) oxidation and oxidized LDL (oxLDL) phagocytosis into macrophage than fructose-treated apoA-I (f-A-I). In the lipid-free state, t-A-I and f-A-I showed more multimerized band without crosslinking. Since t-A-I lost its phospholipid binding ability, the rHDL formation was not as successful as f-A-I. However, injecting t-A-I showed more antioxidant activities in zebrafish embryo under the presence of oxLDL. Three weeks of consumption of fructose (50% of wt in Tetrabit/4% cholesterol) showed a 14% elevation of serum triacylglycerol (TG), while tagatose-administered group showed 30% reduction in serum TG compared to high cholesterol control. Fructose-fed group showed the biggest area of Oil Red O staining with the intensity as strong as the HCD control. However, tagatose-consumed group showed much lesser Oil Red O-stained area with the reduction of lipid accumulation. In conclusion, although tagatose treatment caused modification of apoA-I, the functional loss was not as much severe as the fructose treatment in macrophage cell model, zebrafish embryo, and hypercholesterolemic zebrafish model.
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26
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Putative identification of components in Zengye Decoction and their effects on glucose consumption and lipogenesis in insulin-induced insulin-resistant HepG2 cells. J Chromatogr B Analyt Technol Biomed Life Sci 2018; 1073:145-153. [DOI: 10.1016/j.jchromb.2017.12.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/29/2017] [Accepted: 12/10/2017] [Indexed: 11/19/2022]
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27
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Mašek T, Filipović N, Vuica A, Starčević K. Effects of treatment with sucrose in drinking water on liver histology, lipogenesis and lipogenic gene expression in rats fed high-fiber diet. Prostaglandins Leukot Essent Fatty Acids 2017; 116:1-8. [PMID: 28088289 DOI: 10.1016/j.plefa.2016.11.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/09/2016] [Accepted: 11/21/2016] [Indexed: 11/16/2022]
Abstract
We studied the influence of sucrose in drinking water on liver histology, fatty acid profile and lipogenic genes expression in rats maintained on high-fiber. The experimental groups were: control group (water) and sucrose group (sucrose solution in drinking water, 30% w/v). Liver histology of sucrose treated rats revealed steatosis and increased number of αSMA immunoreactive cells without the signs of fibrosis. Sucrose treatment increased de novo lipogenesis, lipid peroxidation and MUFA content and decreased PUFA content, C18:2n6 and C20:4n6 content in total phospholipids and phosphatidylethanolamine and C18:2n6 content in cardiolipin. RT-qPCR revealed increase in Δ-9-desaturase and SREBP1c gene expression and decrease in the Δ-5-desaturase and elongase 5 expression. Treatment with sucrose extensively changes fatty acid composition of hepatic lipid and phospholipid classes including cardiolipin, increases oxidative stress and causes pathological changes in liver in rats maintained on high-fiber diet.
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Affiliation(s)
- Tomislav Mašek
- Department of Animal Nutrition and Dietetics, University of Zagreb, Faculty of Veterinary Medicine, Heinzelova 55, 10000 Zagreb, Croatia.
| | - Natalija Filipović
- Department of Anatomy, Histology and Embryology, University of Split, School of Medicine, Split, Croatia
| | - Ana Vuica
- Department of Anatomy, Histology and Embryology, University of Split, School of Medicine, Split, Croatia
| | - Kristina Starčević
- Department of Animal Husbandry, University of Zagreb Faculty, of Veterinary Medicine, Zagreb, Croatia
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28
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Application of an In Vivo Hepatic Triacylglycerol Production Method in the Setting of a High-Fat Diet in Mice. Nutrients 2016; 9:nu9010016. [PMID: 28036028 PMCID: PMC5295060 DOI: 10.3390/nu9010016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/02/2016] [Accepted: 12/21/2016] [Indexed: 12/21/2022] Open
Abstract
High-fat (HF) diets typically promote diet-induced obesity (DIO) and metabolic dysfunction (i.e., insulin resistance, hypertriglyceridemia, and hepatic steatosis). Dysfunction of triacylglycerol (TAG) metabolism may contribute to the development of hepatic steatosis, via increased de novo lipogenesis or repackaging of circulating nonesterified fatty acids (NEFAs). Hepatic TAG production (HTP) rate can be assessed through injecting mice with nonionic detergents that inhibit tissue lipoprotein lipase. Potential confounding effects of detergent-based HTP tests (HTPTs) used in longitudinal studies—including the impact on food intake, energy balance, and weight gain—have not been reported. To examine this, male C57BL/6J mice were fed a 10% or 60% kcal diet. After 4 weeks, the mice underwent an HTPT via poloxamer 407 intraperitoneal injections (1000 mg/kg). Weight gain, energy intake, and postabsorptive TAG levels normalized 7–10 days post-HTPT. The post-HTPT recovery of body weight and energy intake suggest that, in metabolic phenotyping studies, any additional sample collection should occur at least 7–10 days after the HTPT to reduce confounding effects. Diet-specific effects on HTP were also observed: HF-fed mice had reduced HTP, plasma TAG, and NEFA levels compared to controls. In conclusion, the current study highlights the procedural and physiological complexities associated with studying lipid metabolism using a HTPT in the DIO mouse model.
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29
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Alwahsh SM, Gebhardt R. Dietary fructose as a risk factor for non-alcoholic fatty liver disease (NAFLD). Arch Toxicol 2016; 91:1545-1563. [PMID: 27995280 DOI: 10.1007/s00204-016-1892-7] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 11/08/2016] [Indexed: 12/16/2022]
Abstract
Glucose is a major energy source for the entire body, while fructose metabolism occurs mainly in the liver. Fructose consumption has increased over the last decade globally and is suspected to contribute to the increased incidence of non-alcoholic fatty liver disease (NAFLD). NAFLD is a manifestation of metabolic syndrome affecting about one-third of the population worldwide and has progressive pathological potential for liver cirrhosis and cancer through non-alcoholic steatohepatitis (NASH). Here we have reviewed the possible contribution of fructose to the pathophysiology of NAFLD. We critically summarize the current findings about several regulators, and their potential mechanisms, that have been studied in humans and animal models in response to fructose exposure. A novel hypothesis on fructose-dependent perturbation of liver regeneration and metabolism is advanced. Fructose intake could affect inflammatory and metabolic processes, liver function, gut microbiota, and portal endotoxin influx. The role of the brain in controlling fructose ingestion and the subsequent development of NAFLD is highlighted. Although the importance for fructose (over)consumption for NAFLD in humans is still debated and comprehensive intervention studies are invited, understanding of how fructose intake can favor these pathological processes is crucial for the development of appropriate noninvasive diagnostic and therapeutic approaches to detect and treat these metabolic effects. Still, lifestyle modification, to lessen the consumption of fructose-containing products, and physical exercise are major measures against NAFLD. Finally, promising drugs against fructose-induced insulin resistance and hepatic dysfunction that are emerging from studies in rodents are reviewed, but need further validation in human patients.
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Affiliation(s)
- Salamah Mohammad Alwahsh
- Faculty of Medicine, Institute of Biochemistry, University of Leipzig, Johannisallee 30, 04103, Leipzig, Germany. .,MCR Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Dr, EH16 4UU Edinburgh, UK.
| | - Rolf Gebhardt
- Faculty of Medicine, Institute of Biochemistry, University of Leipzig, Johannisallee 30, 04103, Leipzig, Germany.
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30
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Delbridge LMD, Benson VL, Ritchie RH, Mellor KM. Diabetic Cardiomyopathy: The Case for a Role of Fructose in Disease Etiology. Diabetes 2016; 65:3521-3528. [PMID: 27879401 DOI: 10.2337/db16-0682] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 09/09/2016] [Indexed: 11/13/2022]
Abstract
A link between excess dietary sugar and cardiac disease is clearly evident and has been largely attributed to systemic metabolic dysregulation. Now a new paradigm is emerging, and a compelling case can be made that fructose-associated heart injury may be attributed to the direct actions of fructose on cardiomyocytes. Plasma and cardiac fructose levels are elevated in patients with diabetes, and evidence suggests that some unique properties of fructose (vs. glucose) have specific cardiomyocyte consequences. Investigations to date have demonstrated that cardiomyocytes have the capacity to transport and utilize fructose and express all of the necessary proteins for fructose metabolism. When dietary fructose intake is elevated and myocardial glucose uptake compromised by insulin resistance, increased cardiomyocyte fructose flux represents a hazard involving unregulated glycolysis and oxidative stress. The high reactivity of fructose supports the contention that fructose accelerates subcellular hexose sugar-related protein modifications, such as O-GlcNAcylation and advanced glycation end product formation. Exciting recent discoveries link heart failure to induction of the specific high-affinity fructose-metabolizing enzyme, fructokinase, in an experimental setting. In this Perspective, we review key recent findings to synthesize a novel view of fructose as a cardiopathogenic agent in diabetes and to identify important knowledge gaps for urgent research focus.
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Affiliation(s)
- Lea M D Delbridge
- Department of Physiology, University of Melbourne, Victoria, Australia
| | - Vicky L Benson
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Rebecca H Ritchie
- Heart Failure Pharmacology, Baker IDI Heart and Diabetes Institute, Victoria, Australia
| | - Kimberley M Mellor
- Department of Physiology, University of Melbourne, Victoria, Australia
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
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31
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Windemuller F, Xu J, Rabinowitz SS, Hussain MM, Schwarz SM. Lipogenesis in Huh7 cells is promoted by increasing the fructose: Glucose molar ratio. World J Hepatol 2016; 8:838-843. [PMID: 27458503 PMCID: PMC4945503 DOI: 10.4254/wjh.v8.i20.838] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 03/28/2016] [Accepted: 06/14/2016] [Indexed: 02/06/2023] Open
Abstract
AIM To determine whether hepatocyte lipogenesis, in an in vitro cell culture model, is modulated by adjusting culture media monosaccharide content and concentration. METHODS Hepatocytes (Huh7), demonstrating glucose and fructose uptake and lipid biosynthesis, were incubated in culture media containing either glucose alone (0.65-0.72 mmol/L) or isosmolar monosaccharide (0.72 mmol/L) comprising fructose:glucose (F:G) molar ratios ranging from 0.58-0.67. Following a 24-h incubation, cells were harvested and analyzed for total protein, triglyceride (TG) and cholesterol (C) content. Significant differences (P < 0.05) among groups were determined using analysis of variance followed by Dunnett's test for multiple comparisons. RESULTS After a 24 h incubation period, Huh7 cell mass and viability among all experimental groups were not different. Hepatocytes cultured with increasing concentrations of glucose alone did not demonstrate a significant change either in C or in TG content. However, when the culture media contained increasing F:G molar ratios, at a constant total monosaccharide concentration, synthesis both of C and of TG increased significantly [F:G ratio = 0.58, C/protein (μg/μg) = 0.13; F:G = 0.67, C/protein = 0.18, P < 0.01; F:G ratio = 0.58, TG/protein (μg/μg) = 0.06; F:G ratio = 0.67, TG/protein = 0.11, P < 0.01]. CONCLUSION In an in vitro hepatocyte model, glucose or fructose plus glucose support total cell mass and lipogenic activity. Increasing the fructose:glucose molar ratio (but not glucose alone) enhances triglyceride and cholesterol synthesis. These investigations demonstrate fructose promotes hepatocellular lipogenesis, and they provide evidence supporting future, in vivo studies of fructose's role in the development of hepatic steatosis and non-alcoholic fatty liver disease.
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Affiliation(s)
- Fernando Windemuller
- Fernando Windemuller, Jiliu Xu, Simon S Rabinowitz, Steven M Schwarz, Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, State University of New York Downstate Medical Center, Brooklyn, NY 11203, United States
| | - Jiliu Xu
- Fernando Windemuller, Jiliu Xu, Simon S Rabinowitz, Steven M Schwarz, Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, State University of New York Downstate Medical Center, Brooklyn, NY 11203, United States
| | - Simon S Rabinowitz
- Fernando Windemuller, Jiliu Xu, Simon S Rabinowitz, Steven M Schwarz, Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, State University of New York Downstate Medical Center, Brooklyn, NY 11203, United States
| | - M Mahmood Hussain
- Fernando Windemuller, Jiliu Xu, Simon S Rabinowitz, Steven M Schwarz, Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, State University of New York Downstate Medical Center, Brooklyn, NY 11203, United States
| | - Steven M Schwarz
- Fernando Windemuller, Jiliu Xu, Simon S Rabinowitz, Steven M Schwarz, Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, State University of New York Downstate Medical Center, Brooklyn, NY 11203, United States
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32
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Zhao L, Guo X, Wang O, Zhang H, Wang Y, Zhou F, Liu J, Ji B. Fructose and glucose combined with free fatty acids induce metabolic disorders in HepG2 cell: A new model to study the impacts of high-fructose/sucrose and high-fat diets in vitro. Mol Nutr Food Res 2016; 60:909-21. [DOI: 10.1002/mnfr.201500635] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/26/2015] [Accepted: 12/29/2015] [Indexed: 01/22/2023]
Affiliation(s)
- Liang Zhao
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
| | - Xiaoxuan Guo
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
| | - Ou Wang
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
| | | | - Yong Wang
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
| | - Feng Zhou
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
| | - Jia Liu
- China National Research Institute of Food and Fermentation Industries; Beijing P. R. China
| | - Baoping Ji
- Beijing Key Laboratory of Functional Food from Plant Resources; College of Food Science and Nutritional Engineering; China Agricultural University; Beijing P. R. China
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Abstract
Cardiovascular disease (CVD) is the single largest cause of mortality in the United States and worldwide. Numerous risk factors have been identified for CVD, including a number of nutritional factors. Recently, attention has been focused on fructose-containing sugars and their putative link to risk factors for CVD. In this review, we focus on recent studies related to sugar consumption and cardiovascular risk factors including lipids, blood pressure, obesity, insulin resistance, diabetes, and the metabolic syndrome. We then examine the scientific basis for competing recommendations for sugar intake. We conclude that although it appears prudent to avoid excessive consumption of fructose-containing sugars, levels within the normal range of human consumption are not uniquely related to CVD risk factors with the exception of triglycerides, which may rise when simple sugars exceed 20% of energy per day, particularly in hypercaloric settings.
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Affiliation(s)
- James M Rippe
- Rippe Lifestyle Institute, Shrewsbury, MA; Rippe Lifestyle Research Institute of Florida, Celebration, FL; and Department of Biomedical Sciences and
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34
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Abstract
A high intake of sugars has been linked to diet-induced health problems. The fructose content in sugars consumed may also affect health, although the extent to which fructose has a particularly significant negative impact on health remains controversial. The aim of this narrative review is to describe the body's fructose management and to discuss the role of fructose as a risk factor for atherosclerosis, type 2 diabetes, and obesity. Despite some positive effects of fructose, such as high relative sweetness, high thermogenic effect, and low glycaemic index, a high intake of fructose, particularly when combined with glucose, can, to a larger extent than a similar glucose intake, lead to metabolic changes in the liver. Increased de novo lipogenesis (DNL), and thus altered blood lipid profile, seems to be the most prominent change. More studies with realistic consumption levels of fructose are needed, but current literature does not indicate that a normal consumption of fructose (approximately 50–60 g/day) increases the risk of atherosclerosis, type 2 diabetes, or obesity more than consumption of other sugars. However, a high intake of fructose, particularly if combined with a high energy intake in the form of glucose/starch, may have negative health effects via DNL.
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35
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Meissen JK, Hirahatake KM, Adams SH, Fiehn O. Temporal metabolomic responses of cultured HepG2 liver cells to high fructose and high glucose exposures. Metabolomics 2015; 11:707-721. [PMID: 26190955 PMCID: PMC4504739 DOI: 10.1007/s11306-014-0729-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
High fructose consumption has been implicated with deleterious effects on human health, including hyperlipidemia elicited through de novo lipogenesis. However, more global effects of fructose on cellular metabolism have not been elucidated. In order to explore the metabolic impact of fructose-containing nutrients, we applied both GC-TOF and HILIC-QTOF mass spectrometry metabolomic strategies using extracts from cultured HepG2 cells exposed to fructose, glucose, or fructose + glucose. Cellular responses were analyzed in a time-dependent manner, incubated in media containing 5.5 mM glucose + 5.0 mM fructose in comparison to controls incubated in media containing either 5.5 mM glucose or 10.5 mM glucose. Mass spectrometry identified 156 unique known metabolites and a large number of unknown compounds, which revealed metabolite changes due to both utilization of fructose and high-carbohydrate loads independent of hexose structure. Fructose was shown to be partially converted to sorbitol, and generated higher levels of fructose-1-phosphate as a precursor for glycolytic intermediates. Differentially regulated ratios of 3-phosphoglycerate to serine pathway intermediates in high fructose media indicated a diversion of carbon backbones away from energy metabolism. Additionally, high fructose conditions changed levels of complex lipids toward phosphatidylethanolamines. Patterns of acylcarnitines in response to high hexose exposure (10.5 mM glucose or glucose/fructose combination) suggested a reduction in mitochondrial beta-oxidation.
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Affiliation(s)
- John K. Meissen
- UC Davis Genome Center, University of California Davis, 451 Health Sciences Dr., Davis, CA 95616, USA
- West Coast Metabolomics Center, University of California Davis, 451 Health Sciences Dr., Davis, CA 95616, USA
| | - Kristin M. Hirahatake
- Department of Nutrition, University of California Davis, One Shields Avenue., Davis, CA 95616, USA
- Obesity and Metabolism Research Unit, USDA-Agricultural Research Service Western Human Nutrition Research Center, 430 W. Health Sciences Dr., Davis, CA 95616, USA
| | - Sean H. Adams
- Department of Nutrition, University of California Davis, One Shields Avenue., Davis, CA 95616, USA
- Obesity and Metabolism Research Unit, USDA-Agricultural Research Service Western Human Nutrition Research Center, 430 W. Health Sciences Dr., Davis, CA 95616, USA
| | - Oliver Fiehn
- UC Davis Genome Center, University of California Davis, 451 Health Sciences Dr., Davis, CA 95616, USA
- West Coast Metabolomics Center, University of California Davis, 451 Health Sciences Dr., Davis, CA 95616, USA
- To whom correspondence should be addressed: Oliver Fiehn, 451 Health Sciences Dr., Davis, CA 95616, Tel: +1-530-754-8258, Fax: +1-530-754-9658,
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Zimmerman AD, Harris RBS. In vivo and in vitro evidence that chronic activation of the hexosamine biosynthetic pathway interferes with leptin-dependent STAT3 phosphorylation. Am J Physiol Regul Integr Comp Physiol 2015; 308:R543-55. [PMID: 25568075 DOI: 10.1152/ajpregu.00347.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously reported that a 2-day peripheral infusion of glucosamine caused leptin resistance in rats, suggesting a role for the hexosamine biosynthetic pathway (HBP) in the development of leptin resistance. Here we tested leptin responsiveness in mice in which HBP activity was stimulated by offering 30% sucrose solution in addition to chow and water or by infusing glucosamine. Mice were leptin resistant after 33 days of access to sucrose. Resistance was associated with increased activity of the HBP and with phosphorylation of transcription factor signal transducer and activator of transcription-3 Tyr705 [pSTAT3(Y705)] but inhibition of suppressor of cytokine signaling 3 in the liver and hypothalamus. Intravenous infusion of glucosamine for 3 h stimulated pSTAT3(Y705) but prevented leptin-induced phosphorylation of STAT3(S727). In an in vitro system, glucose, glucosamine, and leptin each dose dependently increased O-linked β-N-acetylglucosamine (O-GlcNAc) protein and pSTAT3(Y705) in HepG2 cells. To test the effect of glucose on leptin responsiveness cells were incubated in 5.5 mM (LG) or 20 mM (HG) glucose for 18 h and were treated with 0 or 50 ng/ml leptin for 15 min. HG alone and LG + leptin produced similar increases in O-GlcNAc protein, glutamine fructose-6-phosphate amidotransferase (GFAT), and pSTAT3(Y705) compared with LG media. Leptin did not stimulate these proteins in HG cells, suggesting leptin resistance. Leptin-induced pSTAT3(S727) was prevented by HG media. Inhibition of GFAT with azaserine prevented LG + leptin and HG stimulation of pSTAT3. These data demonstrate development of leptin resistance in sucrose-drinking mice and provide new evidence of leptin-induced stimulation of the HBP.
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Affiliation(s)
- Arthur D Zimmerman
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia
| | - Ruth B S Harris
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia
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