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Ramakrishnan K, Sanjeev D, Rehman N, Raju R. A Network Map of Intracellular Alpha-Fetoprotein Signalling in Hepatocellular Carcinoma. J Viral Hepat 2025; 32:e14035. [PMID: 39668590 DOI: 10.1111/jvh.14035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2024] [Revised: 10/03/2024] [Accepted: 10/18/2024] [Indexed: 12/14/2024]
Abstract
Alpha fetoprotein (AFP) is a glycoprotein of foetal origin belonging to the albumin protein family. Serum AFP is a long-conceived early-diagnostic biomarker for HCC with its elevated expression in different liver pathologies ranging from hepatitis viral infections to fibrosis, cirrhosis, and HCC. Beyond their utility as biomarkers, in support of its contribution to these clinical outcomes, the function of AFP as an immune suppressor and inducer of malignant transformation in HCC patients is well reported. Multiple reports show that AFP is secreted by hepatocytes, binds to its cognate receptor, AFP-receptor (AFPR), and exerts its actions. However, there is only limited information available in this context. There is an urgent need to gather more insight into the AFP signalling pathway and consider it a classical intracellular signalling pathway, among others. AFP is a highly potent intracellular molecule that has the potential to bind to many interactors like PTEN, Caspase, RAR, and so on. It has been shown that cellular AFP and secreted AFP have different roles in HCC pathophysiology, and a comprehensive map of the AFP signalling pathway is warranted for further theranostic applications.
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Affiliation(s)
| | - Diya Sanjeev
- Centre for Integrative Omics Data Science, Yenepoya (Deemed to Be University), Mangalore, India
| | - Niyas Rehman
- Centre for Integrative Omics Data Science, Yenepoya (Deemed to Be University), Mangalore, India
| | - Rajesh Raju
- Centre for Integrative Omics Data Science, Yenepoya (Deemed to Be University), Mangalore, India
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2
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Zheng Y, Zhu M, Li M. Effects of alpha-fetoprotein on the occurrence and progression of hepatocellular carcinoma. J Cancer Res Clin Oncol 2020; 146:2439-2446. [DOI: 10.1007/s00432-020-03331-6] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/20/2020] [Indexed: 02/07/2023]
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Abstract
MODY (Maturity Onset Diabetes of the Young) is a type of diabetes resulting from a pathogenic effect of gene mutations. Up to date, 13 MODY genes are known. Gene HNF1A is one of the most common causes of MODY diabetes (HNF1A-MODY; MODY3). This gene is polymorphic and more than 1200 pathogenic and non-pathogenic HNF1A variants were described in its UTRs, exons and introns. For HNF1A-MODY, not just gene but also phenotype heterogeneity is typical. Although there are some clinical instructions, HNF1A-MODY patients often do not meet every diagnostic criteria or they are still misdiagnosed as type 1 and type 2 diabetics. There is a constant effort to find suitable biomarkers to help with in distinguishing of MODY3 from Type 1 Diabetes (T1D) and Type 2 Diabetes (T2D). DNA sequencing is still necessary for unambiguous confirmation of clinical suspicion of MODY. NGS (Next Generation Sequencing) methods brought discoveries of multiple new gene variants and new instructions for their pathogenicity classification were required. The most actual problem is classification of variants with uncertain significance (VUS) which is a stumbling-block for clinical interpretation. Since MODY is a hereditary disease, DNA analysis of family members is helpful or even crucial. This review is updated summary about HNF1A-MODY genetics, pathophysiology, clinics functional studies and variant classification.
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Matsuoka S, Bariuan JV, Nakagiri S, Abd Eldaim MA, Okamatsu-Ogura Y, Kimura K. Linking pathways and processes: Retinoic acid and glucose. MOLECULAR NUTRITION: CARBOHYDRATES 2019:247-264. [DOI: 10.1016/b978-0-12-849886-6.00013-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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A Novel Role for RARα Agonists as Apolipoprotein CIII Inhibitors Identified from High Throughput Screening. Sci Rep 2017; 7:5824. [PMID: 28724938 PMCID: PMC5517646 DOI: 10.1038/s41598-017-05163-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 05/25/2017] [Indexed: 01/23/2023] Open
Abstract
Elevated triglyceride (TG) levels are well-correlated with the risk for cardiovascular disease (CVD). Apolipoprotein CIII (ApoC-III) is a key regulator of plasma TG levels through regulation of lipolysis and lipid synthesis. To identify novel regulators of TG levels, we carried out a high throughput screen (HTS) using an ApoC-III homogenous time resolved fluorescence (HTRF) assay. We identified several retinoic acid receptor (RAR) agonists that reduced secreted ApoC-III levels in human hepatic cell lines. The RARα specific agonist AM580 inhibited secreted ApoC-III by >80% in Hep3B cells with an EC50 ~2.9 nM. In high-fat diet induced fatty-liver mice, AM580 reduced ApoC-III levels in liver as well as in plasma (~60%). In addition, AM580 treatment effectively reduced body weight, hepatic and plasma TG, and total cholesterol (TC) levels. Mechanistically, AM580 suppresses ApoC-III synthesis by downregulation of HNF4α and upregulation of SHP1 expression. Collectively, these studies suggest that an RARα specific agonist may afford a new strategy for lipid-lowering and CVD risk reduction.
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6
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Zhang R, Wang Y, Li R, Chen G. Transcriptional Factors Mediating Retinoic Acid Signals in the Control of Energy Metabolism. Int J Mol Sci 2015; 16:14210-14244. [PMID: 26110391 PMCID: PMC4490549 DOI: 10.3390/ijms160614210] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/10/2015] [Accepted: 06/11/2015] [Indexed: 02/07/2023] Open
Abstract
Retinoic acid (RA), an active metabolite of vitamin A (VA), is important for many physiological processes including energy metabolism. This is mainly achieved through RA-regulated gene expression in metabolically active cells. RA regulates gene expression mainly through the activation of two subfamilies in the nuclear receptor superfamily, retinoic acid receptors (RARs) and retinoid X receptors (RXRs). RAR/RXR heterodimers or RXR/RXR homodimers bind to RA response element in the promoters of RA target genes and regulate their expressions upon ligand binding. The development of metabolic diseases such as obesity and type 2 diabetes is often associated with profound changes in the expressions of genes involved in glucose and lipid metabolism in metabolically active cells. RA regulates some of these gene expressions. Recently, in vivo and in vitro studies have demonstrated that status and metabolism of VA regulate macronutrient metabolism. Some studies have shown that, in addition to RARs and RXRs, hepatocyte nuclear factor 4α, chicken ovalbumin upstream promoter-transcription factor II, and peroxisome proliferator activated receptor β/δ may function as transcriptional factors mediating RA response. Herein, we summarize current progresses regarding the VA metabolism and the role of nuclear receptors in mediating RA signals, with an emphasis on their implication in energy metabolism.
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Affiliation(s)
- Rui Zhang
- State Food and Drug Administration Hubei Center for Medical Equipment Quality Supervision and Testing, 666 High-Tech Avenue, Wuhan 430000, China.
| | - Yueqiao Wang
- Department of Nutrition and Food Hygiene, Wuhan University, 185 East Lake Road, Wuhan 430071, China.
| | - Rui Li
- Department of Nutrition and Food Hygiene, Wuhan University, 185 East Lake Road, Wuhan 430071, China.
| | - Guoxun Chen
- Department of Nutrition, University of Tennessee at Knoxville, 1215 West Cumberland Avenue, Knoxville, TN 37996, USA.
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7
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Priyamvada S, Anbazhagan AN, Gujral T, Borthakur A, Saksena S, Gill RK, Alrefai WA, Dudeja PK. All-trans-retinoic Acid Increases SLC26A3 DRA (Down-regulated in Adenoma) Expression in Intestinal Epithelial Cells via HNF-1β. J Biol Chem 2015; 290:15066-77. [PMID: 25887398 PMCID: PMC4463450 DOI: 10.1074/jbc.m114.566356] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/10/2015] [Indexed: 11/06/2022] Open
Abstract
All-trans-retinoic acid (ATRA) is an active vitamin A derivative known to modulate a number of physiological processes, including growth and development, differentiation, and gene transcription. The protective effect of ATRA in gut inflammation and diarrheal diseases has been documented. In this regard, down-regulated in adenoma (DRA, a key luminal membrane Cl(-) transporter involved in NaCl absorption) has been shown to be suppressed in intestinal inflammation. This suppression of DRA is associated with diarrheal phenotype. Therefore, current studies were undertaken to examine the effects of ATRA on DRA expression. DRA mRNA levels were significantly elevated (∼4-fold) in response to ATRA with induction starting as early as 8 h of incubation. Similarly, ATRA increased DRA protein expression by ∼50%. Furthermore, DRA promoter activity was significantly increased in response to ATRA indicating transcriptional activation. ATRA effects on DRA expression appeared to be mediated via the RAR-β receptor subtype, as ATRA remarkably induced RAR-β mRNA levels, whereas RAR-β knockdown substantially attenuated the ability of ATRA to increase DRA expression. Results obtained from agonist (CH-55) and antagonist (LE-135) studies further confirmed that ATRA exerts its effects through RAR-β. Furthermore, ATRA treatment resulted in a significant increase in HNF-1β mRNA levels. The ability of ATRA to induce DRA expression was inhibited in the presence of HNF-1β siRNA indicative of its involvement in ATRA-induced effects on DRA expression. In conclusion, ATRA may act as an antidiarrheal agent by increasing DRA expression via the RAR-β/HNF-1β-dependent pathway.
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Affiliation(s)
- Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Tarunmeet Gujral
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Alip Borthakur
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612 From the Jesse Brown Veterans Affairs Medical Center
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612 From the Jesse Brown Veterans Affairs Medical Center,
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8
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Tahtouh R, Azzi AS, Alaaeddine N, Chamat S, Bouharoun-Tayoun H, Wardi L, Raad I, Sarkis R, Antoun NA, Hilal G. Telomerase inhibition decreases alpha-fetoprotein expression and secretion by hepatocellular carcinoma cell lines: in vitro and in vivo study. PLoS One 2015; 10:e0119512. [PMID: 25822740 PMCID: PMC4379025 DOI: 10.1371/journal.pone.0119512] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 01/13/2015] [Indexed: 12/13/2022] Open
Abstract
Alpha-fetoprotein (AFP) is a diagnostic marker for hepatocellular carcinoma (HCC). A direct relationship between poor prognosis and the concentration of serum AFP has been observed. Telomerase, an enzyme that stabilizes the telomere length, is expressed by 90% of HCC. The aim of this study was to investigate the effect of telomerase inhibition on AFP secretion and the involvement of the PI3K/Akt/mTOR signaling pathway. Proliferation and viability tests were performed using tetrazolium salt. Apoptosis was determined through the Annexin V assay using flow cytometry. The concentrations of AFP were measured using ELISA kits. The AFP mRNA expression was evaluated using RT-PCR, and cell migration was evaluated using a Boyden chamber assay. The in vivo effect of costunolide on AFP production was tested in NSG mice. Telomerase inhibition by costunolide and BIBR 1532 at 5 and 10 μM decreased AFP mRNA expression and protein secretion by HepG2/C3A cells. The same pattern was obtained with cells treated with hTERT siRNA. This treatment exhibited no apoptotic effect. The AFP mRNA expression and protein secretion by PLC/PRF/5 was decreased after treatment with BIBR1532 at 10 μM. In contrast, no effect was obtained for PLC/PRF/5 cells treated with costunolide at 5 or 10 μM. Inhibition of the PI3K/Akt/mTOR signaling pathway decreased the AFP concentration. In contrast, the MAPK/ERK pathway appeared to not be involved in HepG2/C3A cells, whereas ERK inhibition decreased the AFP concentration in PLC/PRF/5 cells. Modulation of the AFP concentration was also obtained after the inhibition or activation of PKC. Costunolide (30 mg/kg) significantly decreased the AFP serum concentration of NSG mice bearing HepG2/C3A cells. Both the inhibition of telomerase and the inhibition of the PI3K/Akt/mTOR signaling pathway decreased the AFP production of HepG2/C3A and PLC/PRF/5 cells, suggesting a relationship between telomerase and AFP expression through the PI3K/Akt/mTOR pathway.
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MESH Headings
- Aminobenzoates/pharmacology
- Animals
- Apoptosis/drug effects
- Carcinoma, Hepatocellular/drug therapy
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Cell Line, Tumor
- Cell Movement/drug effects
- Enzyme Inhibitors/pharmacology
- Hep G2 Cells
- Humans
- Liver Neoplasms/drug therapy
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Male
- Mice
- Mice, Inbred NOD
- Mice, SCID
- Naphthalenes/pharmacology
- Neoplasm Invasiveness/pathology
- Neoplasm Invasiveness/prevention & control
- Phosphatidylinositol 3-Kinases/metabolism
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- RNA, Small Interfering/genetics
- Sesquiterpenes/pharmacology
- Signal Transduction/drug effects
- TOR Serine-Threonine Kinases/metabolism
- Telomerase/antagonists & inhibitors
- Telomerase/genetics
- Xenograft Model Antitumor Assays
- alpha-Fetoproteins/genetics
- alpha-Fetoproteins/metabolism
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Affiliation(s)
- Roula Tahtouh
- Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Anne-Sophie Azzi
- Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Nada Alaaeddine
- Regenerative Medicine Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Soulaima Chamat
- Faculty of Health Sciences, Lebanese University, Fanar, Lebanon
| | | | - Layal Wardi
- Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Issam Raad
- Department of Infectious Diseases, the University of Texas M. D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Riad Sarkis
- Faculty of Medicine, Saint-Joseph University and Hotel-Dieu de France, Surgery Department, Beirut, Lebanon
| | | | - George Hilal
- Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
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9
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Marchio A, Bertani S, Rojas Rojas T, Doimi F, Terris B, Deharo E, Dejean A, Ruiz E, Pineau P. A peculiar mutation spectrum emerging from young peruvian patients with hepatocellular carcinoma. PLoS One 2014; 9:e114912. [PMID: 25502816 PMCID: PMC4263719 DOI: 10.1371/journal.pone.0114912] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 11/15/2014] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma usually afflicts individuals in their later years following longstanding liver disease. In Peru, hepatocellular carcinoma exists in a unique clinical presentation, which affects patients around age 25 with a normal, healthy liver. In order to deepen our understanding of the molecular processes ongoing in Peruvian liver tumors, mutation spectrum analysis was carried out on hepatocellular carcinomas from 80 Peruvian patients. Sequencing analysis focused on nine genes typically altered during liver carcinogenesis, i.e. ARID2, AXIN1, BRAF, CTNNB1, NFE2L2, H/K/N-RAS, and TP53. We also assessed the transcription level of factors involved in the control of the alpha-fetoprotein expression and the Hippo signaling pathway that controls contact inhibition in metazoans. The mutation spectrum of Peruvian patients was unique with a major class of alterations represented by Insertions/Deletions. There were no changes at hepatocellular carcinoma-associated mutation hotspots in more than half of the specimens analyzed. Furthermore, our findings support the theory of a consistent collapse in the Hippo axis, as well as an expression of the stemness factor NANOG in high alpha-fetoprotein-expressing hepatocellular carcinomas. These results confirm the specificity of Peruvian hepatocellular carcinoma at the molecular genetic level. The present study emphasizes the necessity to widen cancer research to include historically neglected patients from South America, and more broadly the Global South, where cancer genetics and tumor presentation are divergent from canonical neoplasms.
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Affiliation(s)
- Agnès Marchio
- Institut Pasteur, Unité Organisation Nucléaire et Oncogenèse, Paris, France
- INSERM, U993, Paris, France
| | - Stéphane Bertani
- Université de Toulouse, UPS, UMR152 PHARMADEV, Université Toulouse 3, Toulouse, France
- Institut de Recherche pour le Développement, UMR152 PHARMADEV, Lima, Peru
| | - Teresa Rojas Rojas
- Aix-Marseille Université, UMR912 SESSTIM INSERM-IRD-AMU, Centre d′Epidémiologie et de Santé Publique des Armées, Marseille, France
| | - Franco Doimi
- Instituto Nacional de Enfermedades Neoplásicas, Departamento de Patología, Banco de Tejidos Tumorales, Lima, Peru
| | - Benoît Terris
- Assistance Publique-Hôpitaux de Paris, Hôpital Cochin, Service d'Anatomie et Cytologie Pathologiques, Paris, France
| | - Eric Deharo
- Université de Toulouse, UPS, UMR152 PHARMADEV, Université Toulouse 3, Toulouse, France
- Institut de Recherche pour le Développement, UMR152 PHARMADEV, Vientiane, Laos
| | - Anne Dejean
- Institut Pasteur, Unité Organisation Nucléaire et Oncogenèse, Paris, France
- INSERM, U993, Paris, France
| | - Eloy Ruiz
- Instituto Nacional de Enfermedades Neoplásicas, Departamento de Cirugía en Abdomen, Lima, Peru
| | - Pascal Pineau
- Institut Pasteur, Unité Organisation Nucléaire et Oncogenèse, Paris, France
- INSERM, U993, Paris, France
- * E-mail:
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10
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Li R, Zhang R, Li Y, Zhu B, Chen W, Zhang Y, Chen G. A RARE of hepatic Gck promoter interacts with RARα, HNF4α and COUP-TFII that affect retinoic acid- and insulin-induced Gck expression. J Nutr Biochem 2014; 25:964-976. [PMID: 24973045 DOI: 10.1016/j.jnutbio.2014.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 04/13/2014] [Accepted: 04/22/2014] [Indexed: 02/07/2023]
Abstract
The expression of hepatic glucokinase gene (Gck) is regulated by hormonal and nutritional signals. How these signals integrate to regulate the hepatic Gck expression is unclear. We have shown that the hepatic Gck expression is affected by Vitamin A status and synergistically induced by insulin and retinoids in primary rat hepatocytes. We hypothesized that this is mediated by a retinoic acid responsive element (RARE) in the hepatic Gck promoter. Here, we identified the RARE in the hepatic Gck promoter using standard molecular biology techniques. The single nucleotide mutations affecting the promoter activation by retinoic acid (RA) were also determined for detail analysis of protein and DNA interactions. We have optimized experimental conditions for performing electrophoresis mobility shift assay and demonstrated the interactions of the retinoic acid receptor α (RARα), retinoid X receptor α (RXRα), hepatocyte nuclear factor 4α (HNF4α) and chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII) in the rat nuclear extract with this RARE, suggesting their roles in the regulation of Gck expression. Chromatin immunoprecipitation assays demonstrated that recombinant adenovirus-mediated overexpression of RARα, HNF4α and COUP-TFII, but not RXRα, significantly increased their occupancy in the hepatic Gck promoter in primary rat hepatocytes. Overexpression of RARα, HNF4α and COUP-TFII, but not RXRα, also affected the RA- and insulin-mediated Gck expression in primary rat hepatocytes. In summary, this hepatic Gck promoter RARE interacts with RARα, HNF4α and COUP-TFII to integrate Vitamin A and insulin signals.
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Affiliation(s)
- Rui Li
- School of Public Health, Wuhan University, Wuhan, Hubei, 430071, P. R. China; Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
| | - Rui Zhang
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
| | - Yang Li
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
| | - Bing Zhu
- Central Laboratory, Guangzhou Children's Hospital, Guangzhou, Guangdong, P. R. China
| | - Wei Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
| | - Yan Zhang
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
| | - Guoxun Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA.
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11
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Abstract
Mammalian alpha-fetoprotein (AFP) as a fetal specific alpha-globulin has long been used as a serum fetal defect/tumor marker for diagnosis and prediction of liver diseases. In the last decade, clinical and basic research data indicated that AFP acts not only as a biomarker but also as an intracellular signal molecule to play multifarious role in the development of hepatocellular carcinoma.
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12
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Howell M, Li R, Zhang R, Li Y, Chen W, Chen G. The expression of Apoc3 mRNA is regulated by HNF4α and COUP-TFII, but not acute retinoid treatments, in primary rat hepatocytes and hepatoma cells. Mol Cell Biochem 2014; 387:241-250. [PMID: 24234421 DOI: 10.1007/s11010-013-1889-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 11/05/2013] [Indexed: 02/07/2023]
Abstract
Vitamin A status regulates obesity development, hyperlipidemia, and hepatic lipogenic gene expression in Zucker fatty (ZF) rats. The development of hyperlipidemia in acne patients treated with retinoic acid (RA) has been attributed to the induction of apolipoprotein C-III expression. To understand the role of retinoids in the development of hyperlipidemia in ZF rats, the expression levels of several selected RA-responsive genes in the liver and isolated hepatocytes from Zucker lean (ZL) and ZF rats were compared using real-time PCR. The Rarb and Srebp-1c mRNA levels are higher in the liver and isolated hepatocytes from ZF than ZL rats. The Apoc3 mRNA level is only higher in the isolated hepatocytes from ZF than ZL rats. To determine whether dynamic RA production acutely regulates Apoc3 expression, its mRNA levels in response to retinoid treatments or adenovirus-mediated overexpression of hepatocyte nuclear factor 4 alpha (HNF4α) and chicken ovalbumin upstream-transcription factor II (COUP-TFII) were analyzed. Retinoid treatments for 2-6 h did not induce the expression of Apoc3 mRNA. The overexpression of HNF4α or COUP-TFII induced or inhibited Apoc3 expression, respectively. We conclude that short-term retinoid treatments could not induce Apoc3 mRNA expression, which is regulated by HNF4α and COUP-TFII in hepatocytes.
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13
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Chen G. Roles of Vitamin A Metabolism in the Development of Hepatic Insulin Resistance. ISRN HEPATOLOGY 2013; 2013:534972. [PMID: 27335827 PMCID: PMC4890907 DOI: 10.1155/2013/534972] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 08/18/2013] [Indexed: 02/07/2023]
Abstract
The increase in the number of people with obesity- and noninsulin-dependent diabetes mellitus has become a major public health concern. Insulin resistance is a common feature closely associated with human obesity and diabetes. Insulin regulates metabolism, at least in part, via the control of the expression of the hepatic genes involved in glucose and fatty acid metabolism. Insulin resistance is always associated with profound changes of the expression of hepatic genes for glucose and lipid metabolism. As an essential micronutrient, vitamin A (VA) is needed in a variety of physiological functions. The active metablite of VA, retinoic acid (RA), regulates the expression of genes through the activation of transcription factors bound to the RA-responsive elements in the promoters of RA-targeted genes. Recently, retinoids have been proposed to play roles in glucose and lipid metabolism and energy homeostasis. This paper summarizes the recent progresses in our understanding of VA metabolism in the liver and of the potential transcription factors mediating RA responses. These transcription factors are the retinoic acid receptor, the retinoid X receptor, the hepatocyte nuclear factor 4α, the chicken ovalbumin upstream promoter-transcription factor II, and the peroxisome proliferator-activated receptor β/δ. This paper also summarizes the effects of VA status and RA treatments on the glucose and lipid metabolism in vivo and the effects of retinoid treatments on the expression of insulin-regulated genes involved in the glucose and fatty acid metabolism in the primary hepatocytes. I discuss the roles of RA production in the development of insulin resistance in hepatocytes and proposes a mechanism by which RA production may contribute to hepatic insulin resistance. Given the large amount of information and progresses regarding the physiological functions of VA, this paper mainly focuses on the findings in the liver and hepatocytes and only mentions the relative findings in other tissues and cells.
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Affiliation(s)
- Guoxun Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, USA
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14
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Petrescu AD, Huang H, Martin GG, McIntosh AL, Storey SM, Landrock D, Kier AB, Schroeder F. Impact of L-FABP and glucose on polyunsaturated fatty acid induction of PPARα-regulated β-oxidative enzymes. Am J Physiol Gastrointest Liver Physiol 2013; 304:G241-56. [PMID: 23238934 PMCID: PMC3566512 DOI: 10.1152/ajpgi.00334.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Liver fatty acid binding protein (L-FABP) is the major soluble protein that binds very-long-chain n-3 polyunsaturated fatty acids (n-3 PUFAs) in hepatocytes. However, nothing is known about L-FABP's role in n-3 PUFA-mediated peroxisome proliferator activated receptor-α (PPARα) transcription of proteins involved in long-chain fatty acid (LCFA) β-oxidation. This issue was addressed in cultured primary hepatocytes from wild-type, L-FABP-null, and PPARα-null mice with these major findings: 1) PUFA-mediated increase in the expression of PPARα-regulated LCFA β-oxidative enzymes, LCFA/LCFA-CoA binding proteins (L-FABP, ACBP), and PPARα itself was L-FABP dependent; 2) PPARα transcription, robustly potentiated by high glucose but not maltose, a sugar not taken up, correlated with higher protein levels of these LCFA β-oxidative enzymes and with increased LCFA β-oxidation; and 3) high glucose altered the potency of n-3 relative to n-6 PUFA. This was not due to a direct effect of glucose on PPARα transcriptional activity nor indirectly through de novo fatty acid synthesis from glucose. Synergism was also not due to glucose impacting other signaling pathways, since it was observed only in hepatocytes expressing both L-FABP and PPARα. Ablation of L-FABP or PPARα as well as treatment with MK886 (PPARα inhibitor) abolished/reduced PUFA-mediated PPARα transcription of these genes, especially at high glucose. Finally, the PUFA-enhanced L-FABP distribution into nuclei with high glucose augmentation of the L-FABP/PPARα interaction reveals not only the importance of L-FABP for PUFA induction of PPARα target genes in fatty acid β-oxidation but also the significance of a high glucose enhancement effect in diabetes.
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Affiliation(s)
- Anca D. Petrescu
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Huan Huang
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Gregory G. Martin
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Avery L. McIntosh
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Stephen M. Storey
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Danilo Landrock
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
| | - Ann B. Kier
- 2Department of Pathobiology, Texas A&M University, TVMC, College Station, Texas
| | - Friedhelm Schroeder
- 1Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, Texas; and
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15
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Yuan W, Heesom K, Phillips R, Chen L, Trinder J, López Bernal A. Low abundance plasma proteins in labour. Reproduction 2012; 144:505-18. [DOI: 10.1530/rep-12-0114] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Every year, millions of births worldwide are complicated by prematurity or difficult post-term deliveries, resulting in a high incidence of perinatal mortality and morbidity. Our poor understanding of human parturition is a key reason for our inability to improve the management of preterm and post-term birth. In this study, we used proteomic techniques to look into protein changes in placental blood plasma obtained from women before or after spontaneous or induced labour, with vaginal or caesarean section deliveries. Our aim was to understand the basic mechanisms of human parturition regardless of whether the signals that trigger labour are of maternal and/or fetal origin. We found proteins from 33 genes with significantly altered expression profiles in relation to mode of labour and delivery. Most changes in labour occurred in proteins associated with ‘immune and defence responses’. Although the signal transduction and regulation of these pathways varied among modes of delivery, hepatocyte nuclear factor 1 homeobox A emerged as a shared protein in the mechanism of labour. Moreover, several apolipoproteins such as apolipoprotein A-IV and APOE were found to change with labour, and these changes were also confirmed in maternal plasma. This study has identified significant protein changes in placental intervillous plasma with labour and has revealed several pathways related to human parturition.
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16
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Knutson DC, Clagett-Dame M. atRA Regulation of NEDD9, a gene involved in neurite outgrowth and cell adhesion. Arch Biochem Biophys 2008; 477:163-74. [PMID: 18585997 DOI: 10.1016/j.abb.2008.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 06/10/2008] [Accepted: 06/11/2008] [Indexed: 12/01/2022]
Abstract
We previously identified NEDD9 (RAINB2/HEF1/Cas-L) as a new downstream target of all-trans retinoic acid (atRA) and its receptors in the human neuroblastoma cell line, SH-SY5Y [R.A. Merrill, A.W.-M. See, M.L. Wertheim, M. Clagett-Dame, Dev. Dyn. 231 (2004) 564-575; R.A. Merrill, J.M. Ahrens, M.E. Kaiser, K.S. Federhart, V.Y. Poon, M. Clagett-Dame, Biol. Chem. 385 (2004) 605-614]. We now provide functional evidence that NEDD9 is directly regulated by atRA through a complex retinoic acid response element (RARE) located in the NEDD9 proximal promoter and consisting of four conserved half-sites separated by 1, 5, and 1 intervening base pairs. We show that a region of the human NEDD9 promoter from -1670 to +15 is sufficient to confer atRA-responsiveness and that a complex RARE located from -475 to -445 is necessary for this effect. While mutation of any one half-site does not eliminate complex formation in electrophoretic mobility shift assays (EMSA); these same mutations, when tested in transient transfection assays, markedly decrease atRA-responsiveness. Finally, chromatin immunoprecipitation (ChIP) assays demonstrate that RAR and RXR are bound to the RARE in cells.
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Affiliation(s)
- D C Knutson
- Interdepartmental Graduate Program in Nutritional Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706-1544, USA
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17
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Shen H, Luan F, Liu H, Gao L, Liang X, Zhang L, Sun W, Ma C. ZHX2 is a repressor of alpha-fetoprotein expression in human hepatoma cell lines. J Cell Mol Med 2008; 12:2772-80. [PMID: 18194454 PMCID: PMC3828890 DOI: 10.1111/j.1582-4934.2008.00233.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The zinc-fingers and homeoboxes 2 (ZHX2) protein was shown previously to be involved in postnatal repression of α-fetoprotein (AFP) in mice. More recently, loss of ZHX2 expression was often found in human hepatcellular carcinoma (HCC), where AFP is frequently reactivated. Using HepG2 and HepG2.2.15, which express high AFP levels, we show that ZHX2 overexpression significantly decreases of AFP secretion in a dose dependent manner. Furthermore, using LO2 and SMMC7721 cells, which express low AFP levels, we use siRNA inhibition to show that AFP is de-repressed when ZHX2 levels are reduced. This represents the first direct evidence that ZHX2 represses AFP. Co-transfections of ZHX2 and AFP-luciferase reporter genes demonstrate ZHX2 repression is governed by the AFP promoter and requires intact HNF1 binding sites. These data support the idea that ZHX2 contributes to AFP repression in the liver after birth and may also be involved in AFP reactivation in liver cancer.
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Affiliation(s)
- H Shen
- Institute of Immunology, School of Medicine, Shandong University, Wenhua Xi Road, Jinan, PR China
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18
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Yu M, Wang J, Li W, Yuan YZ, Li CY, Qian XH, Xu WX, Zhan YQ, Yang XM. Proteomic screen defines the hepatocyte nuclear factor 1alpha-binding partners and identifies HMGB1 as a new cofactor of HNF1alpha. Nucleic Acids Res 2007; 36:1209-19. [PMID: 18160415 PMCID: PMC2275099 DOI: 10.1093/nar/gkm1131] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Hepatocyte nuclear factor (HNF)-1α is one of the liver-enriched transcription factors involved in many tissue-specific expressions of hepatic genes. The molecular mechanisms for determining HNF1α-mediated transactivation have not been explained fully. To identify unknown proteins that interact with HNF1α, we developed a co-IP-MS strategy to search HNF1α interactions, and high mobility group protein-B1 (HMGB1), a chromosomal protein, was identified as a novel HNF1α-interacting protein. In vitro glutathione S-transferase pull-down and in vivo co-immunoprecipitation studies confirmed an interaction between HMGB1 and HNF1α. The protein–protein interaction was mediated through the HMG box domains of HMGB1 and the homeodomain of HNF1α. Furthermore, electrophoretic mobility shift assay and chromatin-immunoprecipitation assay demonstrated that HMGB1 was recruited to endogenous HNF1α-responsive promoters and enhanced HNF1α binding to its cognate DNA sequences. Moreover, luciferase reporter analyses showed that HMGB1 potentiated the transcriptional activities of HNF1α in cultured cells, and downregulation of HMGB1 by RNA interference specifically affected the HNF1α-dependent gene expression in HepG2 cell. Taken together, these findings raise the intriguing possibility that HMGB1 is a new cofactor of HNF1α and participates in HNF1α-mediated transcription regulation through protein–protein interaction.
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Affiliation(s)
- Miao Yu
- Beijing Institute of Radiation Medicine, Beijing, 100850, Beijing Proteomics Research Center, Beijing, 102206, PR China
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19
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Antoun J, Amet Y, Simon B, Dréano Y, Corlu A, Corcos L, Salaun JP, Plée-Gautier E. CYP4A11 is repressed by retinoic acid in human liver cells. FEBS Lett 2006; 580:3361-7. [PMID: 16712844 DOI: 10.1016/j.febslet.2006.05.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Revised: 04/28/2006] [Accepted: 05/03/2006] [Indexed: 12/31/2022]
Abstract
CYP4A11, the major fatty acid omega-hydroxylase in human liver is involved in the balance of lipids, but its role and regulation are both poorly understood. We studied the effects of retinoids on the regulation of CYP4A11 in the human hepatoma cell line HepaRG. Treatment of HepaRG cells with all-trans-retinoic acid resulted in a strong decrease in CYP4A11 gene expression and apoprotein content and, furthermore, was associated with a 50% decrease in the microsomal lauric acid hydroxylation activity. Such a strong suppression of CYP4A11 expression by retinoids could have a major impact on fatty acid metabolism in the liver.
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Affiliation(s)
- Joseph Antoun
- EA-948 Laboratoire de Biochimie, Faculté de Médecine et des Sciences de la Santé, CS 93837, Brest, France
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20
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Vecchini A, Ceccarelli V, Nocentini G, Riccardi C, Di Nardo P, Binaglia L. Dietary PUFA modulate the expression of proliferation and differentiation markers in Morris 3924A hepatoma cells. Biochim Biophys Acta Mol Cell Biol Lipids 2005; 1737:138-44. [PMID: 16290114 DOI: 10.1016/j.bbalip.2005.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Revised: 10/28/2005] [Accepted: 10/31/2005] [Indexed: 12/30/2022]
Abstract
The effect of dietary polyunsaturated fatty acids on the expression of differentiation and proliferation markers in Morris 3924A hepatoma cells was investigated. ACT/I rats were conditioned 10 days with diets enriched with linoleic acid or alpha-linolenic acid before subcutaneous hepatoma cell transplantation. After 19 days from the inoculum, the mRNA levels of liver-enriched transcription factors and of their target genes were quantified. Both linoleic acid- and linolenic acid-enriched diets induced a decrease of beta-actin, AFP, PCNA, c-myc and of hepatocyte nuclear factors HNF-1alpha and HNF-4alpha mRNA levels in tumor tissue whereas HNF-3beta expression was induced by both dietary treatments. Only the alpha-linolenic acid-enriched diet was effective in reducing c-jun and increasing albumin mRNA levels. Since albumin is a C/EBPalpha target gene, C/EBPalpha gene transcription was evaluated at both protein and mRNA levels. It was found that alpha-linolenic acid-enriched diet did not enhance the C/EBPalpha mRNA content in hepatoma tissue while inducing C/EBPalpha protein expression with an isoform pattern similar to the hepatic phenotype. This evidence implies that alpha-linolenic acid or one of its metabolic products induce albumin synthesis in hepatoma cells by modulating C/EBPalpha gene expression at post-transcriptional level.
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MESH Headings
- Animals
- Biomarkers, Tumor/genetics
- CCAAT-Enhancer-Binding Protein-alpha/genetics
- Cell Differentiation/genetics
- Cell Proliferation
- Dietary Fats, Unsaturated/administration & dosage
- Fatty Acids/analysis
- Fatty Acids, Unsaturated/administration & dosage
- Gene Expression
- Lipids/chemistry
- Liver Neoplasms, Experimental/diet therapy
- Liver Neoplasms, Experimental/genetics
- Liver Neoplasms, Experimental/metabolism
- Liver Neoplasms, Experimental/pathology
- Male
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- Rats
- Rats, Inbred ACI
- Transcription Factors/genetics
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Affiliation(s)
- Alba Vecchini
- Department of Internal Medicine, Section of Biochemistry, University of Perugia, Via del Giochetto, 3, 06126 Perugia, Italy
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21
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Younossi ZM, Gorreta F, Ong JP, Schlauch K, Del Giacco L, Elariny H, Van Meter A, Younoszai A, Goodman Z, Baranova A, Christensen A, Grant G, Chandhoke V. Hepatic gene expression in patients with obesity-related non-alcoholic steatohepatitis. Liver Int 2005; 25:760-771. [PMID: 15998427 DOI: 10.1111/j.1478-3231.2005.01117.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is among the most common causes of chronic liver disease. NAFLD includes a spectrum of clinicopathologic syndromes that includes non-alcoholic steatohepatitis (NASH) that has potential for progression. The pathogenesis of NASH is poorly characterized. AIM This study was designed to identify differences in hepatic gene expression in patients with NASH and to relate such differences to their clinical characteristics. DESIGN Consecutive patients undergoing bariatric surgery were prospectively recruited. Extensive clinical data and two liver biopsy specimens were obtained at the time of enrollment. A single hepatopathologist reviewed and classified the liver biopsies. Patients with excessive alcohol use and other causes of liver disease were excluded. A group of 29 NASH patients, 12 with steatosis alone, seven obese controls and six non-obese controls were selected for further investigation. Customized cDNA microarrays containing 5220 relevant genes were designed specifically for this study. Microarray experiments were run in triplicate for each sample and a selected group of genes were confirmed using real-time PCR. OUTCOME MEASURE Differential hepatic gene expressions in patients with NASH as compared with controls. RESULTS Thirty-four genes with significant differential expression were identified in patients with NASH when compared with non-obese controls. Moreover, 19 of these genes showed no significant expression differences in obese vs. non-obese controls, suggesting a stronger association of these genes to NASH. CONCLUSIONS Several differentially expressed genes in patients with NASH are related to lipid metabolism and extracellular matrix remodeling. Additionally, genes related to liver regeneration, apoptosis, and the detoxification process were differentially expressed. These findings may help clarify the molecular pathogenesis of NASH and identify potential targets for therapeutic intervention.
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Affiliation(s)
- Zobair M Younossi
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, VA, USA
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22
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Kang MJ, Lee DY, Joo WA, Kim CW. Plasma Protein Level Changes in Waste Incineration Workers Exposed to 2,3,7,8-Tetrachlorodibenzo-p-dioxin. J Proteome Res 2005; 4:1248-55. [PMID: 16083274 DOI: 10.1021/pr049756d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) is a chemical compound which is known to induce severe reproductive and developmental problems, immune system damage, and interference with regulatory hormones. To characterize changes in the expression of plasma proteins caused by exposure to TCDD, we analyzed plasma samples from workers at municipal incinerators using two-dimensional gel electrophoresis (2-DE). Proteins exhibiting differences in expression were identified by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray ionization quadrupole (ESI-Q) TOF mass spectrometry. One newly expressed protein was identified as the adrenomedulin binding protein (AMBP). Seven overexpressed proteins were identified in this study, and the most overexpressed protein was identified as alpha-fetoprotein (AFP). In addition, we cultured HepG2 cells in the presence of TCDD, to determine the effects of TCDD on the AFP and albumin expression in mRNA and protein levels, via RT-PCR and Western blotting, respectively. TCDD treatment resulted in an increase in the mRNA and protein expression levels of AFP, but reduced albumin expression. According to our results, exposure to TCDD may induce liver disease or cancer, and the proteins identified in this study could help reveal the mechanisms underlying TCDD toxicity.
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Affiliation(s)
- Mee Jeong Kang
- School of Life Sciences and Biotechnology, Korea University, 1-5 Anam-dong, Sungbuk-gu, Seoul 136-701 Seoul, Korea
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23
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Plumb-Rudewiez N, Clotman F, Strick-Marchand H, Pierreux CE, Weiss MC, Rousseau GG, Lemaigre FP. Transcription factor HNF-6/OC-1 inhibits the stimulation of the HNF-3alpha/Foxa1 gene by TGF-beta in mouse liver. Hepatology 2004; 40:1266-74. [PMID: 15562441 DOI: 10.1002/hep.20459] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A network of liver-enriched transcription factors controls differentiation and morphogenesis of the liver. These factors interact via direct, feedback, and autoregulatory loops. Previous work has suggested that hepatocyte nuclear factor (HNF)-6/OC-1 and HNF-3alpha/FoxA1 participate coordinately in this hepatic network. We investigated how HNF-6 controls the expression of Foxa1. We observed that Foxa1 expression was upregulated in the liver of Hnf6(-/-) mouse embryos and in bipotential mouse embryonic liver (BMEL) cell lines derived from embryonic Hnf6(-/-) liver, suggesting that HNF-6 inhibits the expression of Foxa1. Because no evidence for a direct repression of Foxa1 by HNF-6 was found, we postulated the existence of an indirect mechanism. We found that the expression of a mediator and targets of the transforming growth factor beta (TGF-beta) signaling was increased both in Hnf6(-/-) liver and in Hnf6(-/-) BMEL cell lines. Using these cell lines, we demonstrated that TGF-beta signaling was increased in the absence of HNF-6, and that this resulted from upregulation of TGF-beta receptor II expression. We also found that TGF-beta can stimulate the expression of Foxa1 in Hnf6(+/+) cells and that inhibition of TGF-beta signaling in Hnf6(-/-) cells down-regulates the expression of Foxa1. In conclusion, we propose that Foxa1 upregulation in the absence of HNF-6 results from increased TGF-beta signaling via increased expression of the TGF-beta receptor II. We further conclude that HNF-6 inhibits Foxa1 by inhibiting the activity of the TGF-beta signaling pathway. This identifies a new mechanism of interaction between liver-enriched transcription factors whereby one factor indirectly controls another by modulating the activity of a signaling pathway.
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Affiliation(s)
- Nicolas Plumb-Rudewiez
- Hormone and Metabolic Research Unit, Institute of Cellular Pathology and Université Catholique de Louvain, Brussels, Belgium
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24
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Wu Y, Cai Y, Aguilo J, Dai T, Ao Y, Wan YJY. RXRα mRNA expression is associated with cell proliferation and cell cycle regulation in Hep3B cell. Exp Mol Pathol 2004; 76:24-8. [PMID: 14738865 DOI: 10.1016/j.yexmp.2003.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Retinoids are well-characterized differentiation and anti-proliferation agents. The functional role of retinoid x receptor alpha (RXRalpha) in cell proliferation and cell cycle regulation is not well understood. Using human Hep3B cell line, we showed that the mRNA level of RXRalpha was closely associated with cell growth. RXRalpha mRNA expression elevated along with the proliferation of Hep3B cells. This association was most evident in RXRalpha and was also noted with retinoic acid (RA) receptor alpha (RARalpha), but not found in other RARs and RXRs. The expression of RXRalpha and cyclin A mRNA was co-regulated when Hep3B cells were cultured in serum-free medium. The mRNA levels of RXRalpha and cyclin A appeared to be highest in G1/S phase in Hep3B cells treated by aphidicolin. Taken together, our data suggest that RXRalpha may be actively involved in cell proliferation and cell cycle regulation in Hep3B cells.
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Affiliation(s)
- Yong Wu
- Department of Pathology, Harbor-UCLA Medical Center, Torrance, CA 90503, USA
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25
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Divine JK, McCaul SP, Simon TC. HNF-1alpha and endodermal transcription factors cooperatively activate Fabpl: MODY3 mutations abrogate cooperativity. Am J Physiol Gastrointest Liver Physiol 2003; 285:G62-72. [PMID: 12646418 DOI: 10.1152/ajpgi.00074.2003] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hepatocyte nuclear factor (HNF)-1alpha plays a central role in intestinal and hepatic gene regulation and is required for hepatic expression of the liver fatty acid binding protein gene (Fabpl). An Fabpl transgene was directly activated through cognate sites by HNF-1alpha and HNF-1beta, as well as five other endodermal factors: CDX-1, C/EBPbeta, GATA-4, FoxA2, and HNF-4alpha. HNF-1alpha activated the Fabpl transgene by as much as 60-fold greater in the presence of the other five endodermal factors than in their absence, accounting for up to one-half the total transgene activation by the group of six factors. This degree of synergistic interaction suggests that multifactor cooperativity is a critical determinant of endodermal gene activation by HNF-1alpha. Mutations in HNF-1alpha that result in maturity onset diabetes of the young (MODY3) provide evidence for the in vivo significance of these synergistic interactions. An R131Q HNF-1alpha MODY3 mutant exhibits complete loss of synergistic activation in concert with the other endodermal transcription factors despite wild-type transactivation ability in their absence. Furthermore, whereas wild-type HNF-1alpha exhibited pairwise cooperative synergy with each of the other five factors, the R131Q mutant could synergize only with GATA-4 and C/EBPbeta. Selective loss of synergy with other endodermal transcription factors accompanied by retention of native transactivation ability in an HNF-1alpha MODY mutant suggests in vivo significance for cooperative synergy.
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Affiliation(s)
- Joyce K Divine
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
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26
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Lu SY, Sui YF, Li ZS, Pan CE, Ye J, Wang WY. Construction of a regulable gene therapy vector targeting for hepatocellular carcinoma. World J Gastroenterol 2003; 9:688-91. [PMID: 12679911 PMCID: PMC4611429 DOI: 10.3748/wjg.v9.i4.688] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To construct a gene modified hepatocellular carcinoma (HCC) specific EGFP expression vector regulated by abbreviated cis-acting element of AFP gene.
METHODS: The minimal essential DNA segments of AFP gene enhancer and promoter were synthesized through PCR from Genome DNA of HepG2 cells. Gene fragments were then cloned into the multiple cloning site of non-promoter EGFP vector pEGFP-1. Recombinant plasmid was transferred into positive or negative AFP cell lines by means of lipofectamine. The expression of EGFP was tested by fluorescence microscope and flow cytometry. The effect of all-trans retinoic acid (ATRA) on the expression of EGFP was tested in different concentrations.
RESULTS: By the methods of restriction digestion and sequence analyses we confirmed that the length, position and orientation of inserted genes of cis-acting element of AFP were all correct. The transcription of EGFP was under the control of AFP cis-acting element. The expressing EGFP can only been detected in AFP producing hepatoma cells. The expression rate of EGFP in G418 screened cell line was 34.9% ± 4.1%. 48 h after adding 1 × 10-7 M retinoic acid, EGFP expression rate was 14.7% ± 3.5%. The activity of AFP gene promoter was significantly suppressed by addition of 1 × 10-7 M retinoic acid (P < 0.05, P = 0.003, t = 6.488).
CONCLUSION: This recombinant expression vector can be used as a gene therapy vector for HCC. The expression of tumor killing gene will be confined within the site of tumor and the activity of which can be regulated by retinoic acid.
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Affiliation(s)
- Shao-Ying Lu
- Department of Pathology, Fourth Military Medical University, Xi'an 710032, China
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27
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Li MS, Li PF, He SP, Du GG, Li G. The promoting molecular mechanism of alpha-fetoprotein on the growth of human hepatoma Bel7402 cell line. World J Gastroenterol 2002; 8:469-475. [PMID: 12046072 PMCID: PMC4656423 DOI: 10.3748/wjg.v8.i3.469] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2002] [Revised: 02/13/2002] [Accepted: 03/05/2002] [Indexed: 02/06/2023] Open
Abstract
AIM The goal of this study was to characterize the AFP receptor, its possible signal transduction pathway and its proliferative functions in human hepatoma cell line Bel 7402. METHODS Cell proliferation enhanced by AFP was detected by MTT assay, 3H-thymidine incorporation and S-stage percentage of cell cycle analysis. With radioactive labeled 125I-AFP for receptor binding assay; cAMP accumulation, protein kinase A activity were detected by radioactive immunosorbent assay and the change of intracellular free calcium (Ca2+i) was monitored by scanning fluorescence intensity under TCS-NT confocal microscope. The expression of oncogenes N- ras, p 53, and p21( ras ) in the cultured cells in vitro were detected by Northern blotting and Western blotting respectively. RESULTS It was demonstrated that AFP enhanced the proliferation of human hepatoma Bel 7402 cell in a dose dependent fashion as shown in MTT assay, (3)H-thymidine incorporation and S-phase percentage up to 2-fold. Two subtypes of AFP receptors were identified in the cells with Kds of 1.3 x 10(-9)mol.L(-1) and 9.9 x10(-8)mol. (-1)L respectively. Pretreatment of cells with AFP resulted in a significant increase (625%) in cAMP accumulation. The activity of protein kinase A activity were increased up to 37.5, 122.6, 73.7 and 61.2% at treatment time point 2, 6, 12 and 24 hours. The level of intracellular calcium were elevated after the treatment of alpha-fetoprotein and achieved to 204% at 4 min. The results also showed that AFP(20mg.L(-1)) could upregulate the expression of N- ras oncogenes and p 53 and p21( ras ) in Bel 7402 cells. In the later case,the alteration were 81.1%(12h) and 97.3%(12h) respectively compared with control. CONCLUSION These results demonstrate that AFP is a potential growth factor to promote the proliferation of human hepatoma Bel 7402 cells. Its growth-regulatory effects are mediated by its specific plasma membrane receptors coupled with its transmembrane signaling transduction through the pathway of cAMP-PKA and intracellular calcium to regulate the expression of oncogenes.
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Affiliation(s)
- Meng-Sen Li
- Department of Biochemistry, Hainan Medical College, Hainan, China
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Hatzis P, Talianidis I. Regulatory mechanisms controlling human hepatocyte nuclear factor 4alpha gene expression. Mol Cell Biol 2001; 21:7320-30. [PMID: 11585914 PMCID: PMC99906 DOI: 10.1128/mcb.21.21.7320-7330.2001] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Hepatocyte nuclear factor 4alpha (HNF-4alpha) (nuclear receptor 2A1) is an essential regulator of hepatocyte differentiation and function. Genetic and molecular evidence suggests that the tissue-restricted expression of HNF-4alpha is regulated mainly at the transcriptional level. As a step toward understanding the molecular mechanism involved in the transcriptional regulation of the human HNF-4alpha gene, we cloned and analyzed a 12.1-kb fragment of its upstream region. Major DNase I-hypersensitive sites were found at the proximal promoter, the first intron, and the more-upstream region comprising kb -6.5, -8.0, and -8.8. By the use of reporter constructs, we found that the proximal-promoter region was sufficient to drive high levels of hepatocyte-specific transcription in transient-transfection assays. DNase I footprint analysis and electrophoretic mobility shift experiments revealed binding sites for HNF-1alpha and -beta, Sp-1, GATA-6, and HNF-6. High levels of HNF-4alpha promoter activity were dependent on the synergism between either HNF-1alpha and HNF-6 or HNF-1beta and GATA-6, which implies that at least two alternative mechanisms may activate HNF-4alpha gene transcription. Chromatin immunoprecipitation experiments with human hepatoma cells showed stable association of HNF-1alpha, HNF-6, Sp-1, and COUP-TFII with the promoter. The last factor acts as a repressor via binding to a newly identified direct repeat 1 (DR-1) sequence of the human promoter, which is absent in the mouse homologue. We present evidence that this sequence is a bona fide retinoic acid response element and that HNF-4alpha expression is upregulated in vivo upon retinoic acid signaling.
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Affiliation(s)
- P Hatzis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, 711 10 Herakleion, Crete, Greece
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Nakabayashi H, Koyama Y, Sakai M, Li HM, Wong NC, Nishi S. Glucocorticoid stimulates primate but inhibits rodent alpha-fetoprotein gene promoter. Biochem Biophys Res Commun 2001; 287:160-72. [PMID: 11549270 DOI: 10.1006/bbrc.2001.5564] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucocorticoids inhibit rodent alpha-fetoprotein (AFP) gene activity but stimulate expression of the human homologue. Like human, activity of the AFP promoter from other primates was stimulated by the synthetic glucocorticoid dexamethasone (Dex) in various cell lines. A glucocorticoid responsive element (GRE) is located within 180 bp upstream of the transcription initiation site of all AFP genes examined. Comparative analysis of the GRE in the two different groups of promoters revealed a common 3' hexamer, 5'-TGTCCT-3', but the 5' hexamers were different. This difference converts the rodent GRE to a DR-1 motif. DR-1 is a binding site for members of the nuclear receptor superfamily including the orphan receptor hepatocyte nuclear factor-4 (HNF-4). The presence of DR-1 in the rodent but not human may underlie the opposite actions of Dex on the AFP promoter. We tested this hypothesis using a transient transfection assay. In hepatoma cells that expressed GR and HNF-4, reporter-activity was inhibited by Dex. The same construct in nonhepatoma cells was strongly induced by over expression of HNF-4 and the induced activity was inhibited by Dex. The findings show that Dex induction of human AFP is mediated by a GRE. But Dex repression of the rodent promoter requires a DR-1 motif that interacts with GR and HNF-4.
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Affiliation(s)
- H Nakabayashi
- Department of Biochemistry, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo 060-8638, Japan.
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Osawa Y, Nagaki M, Banno Y, Nozawa Y, Moriwaki H, Nakashima S. Sphingosine kinase regulates hepatoma cell differentiation: roles of hepatocyte nuclear factor and retinoid receptor. Biochem Biophys Res Commun 2001; 286:673-7. [PMID: 11520048 DOI: 10.1006/bbrc.2001.5451] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In hepatoma Huh-7 cells, inhibition of sphingosine kinase (SphK) activity by N,N-dimethylsphingosine (DMS) resulted in up-regulated production of liver-specific serum proteins including albumin and alpha-fetoprotein (AFP). The changes in these protein levels coincided well with those of two liver-enriched transcription factors, hepatocyte nuclear factor (HNF)-1 and -4, which regulate a number of liver-specific genes at the transcriptional level. Moreover, DMS induced the expression of retinoic acid receptor-alpha and retinoid X receptor-alpha. In DMS-treated cells, 9-cis retinoic acid (RA) further enhanced HNF-4alpha and albumin expression but it inhibited AFP accumulation. These results suggest that activation of SphK disengages cells from their liver-specific phenotype, and that 9-cis RA further induces differentiation of hepatoma cells when SphK activity is inhibited.
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Affiliation(s)
- Y Osawa
- First Department of Internal Medicine, Gifu University School of Medicine, Tsukasamachi-40, Gifu 500-8705, Japan
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Memon RA, Moser AH, Shigenaga JK, Grunfeld C, Feingold KR. In vivo and in vitro regulation of sterol 27-hydroxylase in the liver during the acute phase response. potential role of hepatocyte nuclear factor-1. J Biol Chem 2001; 276:30118-26. [PMID: 11406622 DOI: 10.1074/jbc.m102516200] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The host response to infection is associated with several alterations in lipid metabolism that promote lipoprotein production. These changes can be reproduced by lipopolysaccharide (LPS) administration. LPS stimulates hepatic cholesterol synthesis and suppresses the conversion of cholesterol to bile acids. LPS down-regulates hepatic cholesterol 7alpha-hydroxylase, the rate-limiting enzyme in the classic pathway of bile acid synthesis. We now demonstrate that LPS markedly decreases the activity of sterol 27-hydroxylase, the rate-limiting enzyme in the alternate pathway of bile acid synthesis, in the liver of Syrian hamsters. Moreover, LPS progressively decreases hepatic sterol 27-hydroxylase mRNA levels by 75% compared with controls over a 24-h treatment period. LPS also decreases oxysterol 7alpha-hydroxylase mRNA levels in mouse liver. In vitro studies in HepG2 cells demonstrate that tumor necrosis factor and interleukin (IL)-1 decrease sterol 27-hydroxylase mRNA levels by 48 and 80%, respectively, whereas IL-6 has no such effect. The IL-1-induced decrease in sterol 27-hydroxylase mRNA expression occurs early, is sustained for 48 h, and requires very low doses. In vivo IL-1 treatment also lowers hepatic sterol 27-hydroxylase mRNA levels in Syrian hamsters. Studies investigating the molecular mechanisms of LPS-induced decrease in sterol 27-hydroxylase show that LPS markedly decreases mRNA and protein levels of hepatocyte nuclear factor-1 (HNF-1), a transcription factor that regulates sterol 27-hydroxylase, in the liver. Moreover, LPS decreases the binding activity of HNF-1 by 70% in nuclear extracts in hamster liver, suggesting that LPS may down-regulate sterol 27-hydroxylase by decreasing the binding of HNF-1 to its promoter. Coupled with our earlier studies on cholesterol 7alpha-hydroxylase, these data indicate that LPS suppresses both the classic and alternate pathways of bile acid synthesis. A decrease in bile acid synthesis in liver would reduce cholesterol catabolism and thereby contribute to the increase in hepatic lipoprotein production that is induced by LPS and cytokines.
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Affiliation(s)
- R A Memon
- Departments of Medicine, University of California, San Francisco and the Metabolism Section, Department of Veterans Affairs Medical Center, San Francisco, California 94121, USA.
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Qian A, Cai Y, Magee TR, Wan YJ. Identification of retinoic acid-responsive elements on the HNF1alpha and HNF4alpha genes. Biochem Biophys Res Commun 2000; 276:837-42. [PMID: 11027556 DOI: 10.1006/bbrc.2000.3549] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hepatocyte nuclear factor 1alpha (HNF1alpha) and HNF4alpha are liver-selective transcription factors and are essential for hepatocyte differentiation. This study demonstrates that HNF1alpha as well as HNF4alpha genes contain a direct repeat with a space of one nucleotide (DR1)-retinoic acid (RA) response element that can be bound and regulated by RA and retinoid x receptor alpha (RXRalpha) complex. Transient transfection experiments showed that RA increased the promoter activity of the HNF1alpha and HNF4alpha genes in Hep3B cells. Overexpression of RXRalpha further enhanced the activities of both genes. Two putative RXRalpha binding sites on the HNF1alpha (-295 to -276) and HNF4alpha (-418 to -399) genes have been characterized. By transient transfection, both sites positively responded to RA, and overexpression of RXRalpha in Hep3B cells increased the regulatory effect. Gel mobility shift assay demonstrated that these two DR-1 sites could be bound by RXRalpha specifically. These data suggest that the differentiation effect of RA on hepatocyte may be due to direct interaction of RXRalpha with the RA-responsive elements on the HNF1alpha and HNF4alpha genes.
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Affiliation(s)
- A Qian
- Department of Pathology, Harbor-UCLA Medical Center, Torrance, California, 90509, USA
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Abstract
Retinoic acid (RA) induces apoptosis in Hep3B human hepatoma cells. 9-Cis-RA (c-RA) had a similar effect as all-trans-RA (t-RA) in inducing cell death in Hep3B cells. RA-induced Hep3B-cell death was associated with inhibited expression of the hepatocyte nuclear factor 4 (HNF-4) gene. Palmitoyl-CoA ((C16:0)-CoA), the reported HNF-4 ligand, prevented RA-induced apoptosis. The effect of (C16:0)-CoA was specific, since palmitic acid and co-enzyme A had no effect in preventing RA-induced apoptosis. Bovine serum albumin (BSA) also prevented RA-induced apoptosis. However, in contrast to BSA, which induced cell growth, (C16:0)-CoA alone had no effect on cell growth. Investigating the possible role of HNF-4 in apoptosis, the reported HNF-4 antagonist (C18:0)-CoA was employed, and it also prevented RA-induced apoptosis. By transient transfection, overexpression of HNF-4 did not prevent RA-induced apoptosis. The induction and prevention of apoptosis caused by RA and (C16:0)-CoA were associated, respectively with the induction and inhibition of the expression of transforming growth factor beta (TGFbeta), which is known to play a role in apoptosis. Furthermore, RA and (C16:0)-CoA can regulate AP-1, which is a key regulator of the TGFbeta gene. Our data indicate that fatty acyl-CoAs can prevent RA-induced apoptosis and that TGFbeta, rather than HNF-4, may play a role in these regulatory processes. Our data also suggest that (C16:0)-CoA and (C18:0)-CoA are not the agonist and antagonist for HNF4, respectively in the Hep3B cell system.
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Affiliation(s)
- Y J Wan
- Department of Pathology, Harbor-UCLA Medical Center, Torrance, CA 90509, USA.
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Takeda K, Ichiki T, Funakoshi Y, Ito K, Takeshita A. Downregulation of angiotensin II type 1 receptor by all-trans retinoic acid in vascular smooth muscle cells. Hypertension 2000; 35:297-302. [PMID: 10642314 DOI: 10.1161/01.hyp.35.1.297] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
All-trans retinoic acid (atRA) is a biologically active metabolite of vitamin A that plays an important role in cell differentiation and proliferation. Although neointimal formation after balloon injury of rat carotid artery is inhibited by atRA, the mechanisms are not clearly understood. Because the renin-angiotensin system is one of the crucial components of atherosclerosis, we examined the effects of atRA on the expression of angiotensin II type 1 receptor (AT(1)-R) in vascular smooth muscle cells. atRA (1 micromol/L) decreased the AT(1)-R mRNA level by 50% after 24 hours; AT(1)-R number was also reduced to the same extent after 48 hours. atRA markedly suppressed promoter activity of the AT(1)-R promoter-luciferase construct, but AT(1)-R mRNA stability was not affected. Cycloheximide blocked the atRA-induced decrease in AT(1)-R mRNA expression, suggesting that this process requires de novo protein synthesis. Simultaneous treatment with an agonist (Ro40-6055) specific for retinoic acid receptor (RAR) and an agonist (Ro25-7836) specific for retinoid X receptor (RXR) suppressed the AT(1)-R mRNA expression comparable to that with treatment with atRA, suggesting that the RAR/RXR heterodimer mediates the effect of atRA in AT(1)-R downregulation. These results suggest that atRA suppressed AT(1)-R mRNA transcription through new protein synthesis induced by RAR/RXR-dependent transcription. This study provides novel insight into a role of atRA as an important molecule that regulates AT(1)-R gene expression and provides possible mechanisms for the suppression of neointimal formation by atRA.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Aorta, Thoracic/cytology
- Benzoates/pharmacology
- Binding, Competitive/genetics
- CREB-Binding Protein
- Cells, Cultured
- Cycloheximide/pharmacology
- Down-Regulation/drug effects
- Gene Expression Regulation/drug effects
- Lac Operon
- Luciferases/genetics
- Muscle, Smooth, Vascular/chemistry
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Nuclear Proteins/metabolism
- Promoter Regions, Genetic/physiology
- Protein Synthesis Inhibitors/pharmacology
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/genetics
- Receptors, Retinoic Acid/physiology
- Recombinant Fusion Proteins/genetics
- Retinoid X Receptors
- Tetrahydronaphthalenes/pharmacology
- Trans-Activators/metabolism
- Transcription Factors/physiology
- Tretinoin/pharmacology
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Affiliation(s)
- K Takeda
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Higashi-ku, Fukuoka, Japan
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