Natural channel proteins (NCPs) have numerous ion transport modes, but it remains a big challenge to replicate this trait by artificial ion transport systems. Herein, we present an azobenzene-incorporated single-chain random heteropolymers (RHPs)-derived biomimetic K+ channel P3, which can switch between three ion transport states ("ON," "Partially OFF," and "Totally OFF") in both liposomes and cancer cells. The conformational adjustments of P3 activated by light-modulating two groups of supramolecular interactions ((1) hydrogen bonding and π-π interactions; (2) host-guest interactions) realize these switches, resembling the protein mechanisms that govern activity. Underlying molecular mechanisms are the photoisomerization of azobenzene moieties in P3 and their complexation with β-cyclodextrin (β-CD), enabling the exploit of a "one stone (azobenzene moiety), two birds (supramolecular interactions)" strategy. Mechanistic investigations demonstrate that P3-induced substantial K+ efflux (a 50% drop within just 4 min) causes endoplasmic reticulum (ER) stress, intriguing Ca2+ sparks, enhanced reactive oxygen species (ROS), and finally severe mitochondria-dependent apoptosis. This NCP-like channel (P3) is expected to provide new opportunities for a deeper understanding of the internal mechanisms of NCPs, as well as for treating cancer and other diseases.

Systemic autoinflammatory disorders (SAIDs) are a group of diseases that are characterized by recurrent or persistent unprovoked attacks of inflammation resulting from innate immunity dysregulation and leading to significant sequelae in many cases. The concept of autoinflammatory disorders has been widely studied in the last 28 years since the genetic mutation responsible for familial Mediterranean fever (FMF) was discovered. These disorders are mainly hereditary autoinflammatory diseases with key immunological pathways affected and particularly involving inflammasomes, nuclear factor-κB dysregulation and interferon upregulation. This article serves as an overview of pediatric systemic autoinflammatory disorders, their presentation, workup, complications, and therapeutic management.

Advances in genetic analysis have allowed for the rapid identification of mutations responsible for many autoinflammatory disorders. Advances in biomolecular techniques, which have allowed for identifying key players such as inflammasomes, have led to treatment options that have significantly improved morbidity and mortality in affected patients. This review provides an overview of the proposed pathogenesis, presenting features, potential complications and suggested therapies of systemic autoinflammatory disorders. Providers should have a high clinical suspicion for autoinflammatory disorders in children who present with fever, a heightened inflammatory response and negative evaluation for an infectious, malignant, and autoimmune etiology. Understanding and identifying these disorders in a timely manner and implementing prompt treatment allow for the best possible outcome for these patients.

There has been a recent expansion in our understanding of DNA-sensing mechanisms. Mitochondrial dysfunction, oxidative and proteostatic stresses, instability and impaired disposal of nucleoids cause the release of mitochondrial DNA (mtDNA) from the mitochondria in several human diseases, as well as in cell culture and animal models. Mitochondrial DNA mislocalized to the cytosol and/or the extracellular compartments can trigger innate immune and inflammation responses by binding DNA-sensing receptors (DSRs). Here, we define the features that make mtDNA highly immunogenic and the mechanisms of its release from the mitochondria into the cytosol and the extracellular compartments. We describe the major DSRs that bind mtDNA such as cyclic guanosine-monophosphate-adenosine-monophosphate synthase (cGAS), Z-DNA-binding protein 1 (ZBP1), NOD-, LRR-, and PYD- domain-containing protein 3 receptor (NLRP3), absent in melanoma 2 (AIM2) and toll-like receptor 9 (TLR9), and their downstream signaling cascades. We summarize the key findings, novelties, and gaps of mislocalized mtDNA as a driving signal of immune responses in vascular, metabolic, kidney, lung, and neurodegenerative diseases, as well as viral and bacterial infections. Finally, we define common strategies to induce or inhibit mtDNA release and propose challenges to advance the field.

Celiac disease (CD) is an autoimmune disorder that primarily affects the gut of genetically predisposed individuals and is triggered by gliadin peptides (PT) produced by the digestion of gluten. Although inappropriate activation of the immune system is thought to be the main trigger of CD, the interaction between PT and intestinal epithelial cells (IECs) remains a key step. Recently, the possible involvement of ER stress in the pathogenesis of CD has been pointed out, although its role is still largely unclear. Therefore, discovering the molecular mechanism(s) activated in IECs exposed to PT represents a unique opportunity to better understand the disease and define new potential therapeutic targets.

In this study we used three different experimental set-ups: intestinal biopsies from CD patients and non-CD control subjects, an in vitro model, based on human CaCo-2 cells, and an ex vivo model, based on our recently described mouse gut-ex-vivo system (GEVS), with the latter two systems were studied after stimulation with gliadin peptides (PT). To understand the signaling pathways involved we monitor the expression of a number of proteins by qPCR, Western blotting, IF, ELISA or a combination of tests. Specifically, we have analyzed the level of CD, ER stress, tissue permeability, and inflammation markers.

Indeed, our study demonstrated a prompt induction of the transcription factors ATF4, ATF6 and XBP1 in IECs upon PT exposure. Thus, the upregulation of TG2 and downregulation of CFTR were prevented by ER stress inhibition/buffering by a pharmacological chaperone, also leading to restored physiological expression of OCL, CLD-2 and CLD-15, while preventing the expression of IFNγ, IL-15 and IL-17 A.

Overall, our analysis has highlighted the key role of ER stress in the pathogenesis of CD and identified the chemical chaperones as a new potential valuable therapeutic treatment for CD patients.

Traumatic brain injury (TBI) precipitates a neuroinflammatory cascade, with the NLRP3 inflammasome emerging as a critical mediator. This review scrutinizes the complex activation pathways of the NLRP3 inflammasome by underscoring the intricate interplay between calcium signaling, mitochondrial disturbances, redox imbalances, lysosomal integrity, and autophagy. It is hypothesized that a combination therapy approach-integrating NF-κB pathway inhibitors with NLRP3 inflammasome antagonists-holds the potential to synergistically dampen the inflammatory storm associated with TBI.

A comprehensive analysis of literature detailing NLRP3 inflammasome activation pathways and therapeutic interventions was conducted. Empirical evidence supporting the concurrent administration of MCC950 and Rapamycin was reviewed to assess the efficacy of dual-action strategies compared to single-agent treatments.

Findings highlight potassium efflux and calcium signaling as novel targets for intervention, with cathepsin B inhibitors showing promise in mitigating neuroinflammation. Dual therapies, particularly MCC950 and Rapamycin, demonstrate enhanced efficacy in reducing neuroinflammation. Autophagy promotion, alongside NLRP3 inhibition, emerges as a complementary therapeutic avenue to reverse neuroinflammatory damage.

Combination therapies targeting the NLRP3 inflammasome and related pathways offer significant potential to enhance recovery in TBI patients. This review presents compelling evidence for the development of such strategies, marking a new frontier in neuroinflammatory research and therapeutic innovation.

Chronic stress in the central nervous system can lead to neurological dysfunction characterized by spontaneous neuronal cell death. This study investigated the neuroprotective potential of an aqueous extract of Lilium lancifolium Thunberg (ELL) against corticosterone (CORT)-induced pathophysiology in PC12 cells. To assess the neuroprotective effects of ELL, PC12 cells were pretreated with 50 µg/mL of ELL before being exposed to CORT. ELL significantly prevented CORT-induced neuronal cell death by attenuating pro-apoptotic protein expression, lactate dehydrogenase release, and reactive oxygen species generation, while maintaining intact adenosine triphosphate levels. Furthermore, ELL significantly mitigated CORT-induced endoplasmic reticulum (ER) stress responses by attenuating the elevation of unfolded protein responses, intracellular calcium levels, opening of mitochondrial permeability transition pores, and loss of mitochondrial membrane potential. In conclusion, ELL exerts neuroprotective effects by inhibiting apoptosis through the mitigation of CORT-induced ER stress and mitochondrial dysfunction, suggesting that ELL may prevent neuronal damage associated with chronic stress-induced neurotoxicity.

Coeliac disease is an autoimmune disease that is primarily associated with chronic inflammation of the gut, but can also affect organs outside the gut, from the liver to the skin and CNS. The disease is triggered in predisposed individuals by a peptide mixture (PT) derived from the digestion of gliadin, a component of wheat, which is ingested with food. Although the induction of endoplasmic reticulum stress in intestinal epithelial cells (IECs) upon exposure to PT is known, the underlying molecular mechanisms remain unclear. Identifying the key players in this signaling pathway could therefore help to develop a new effective therapeutic strategy for the treatment of CD patients.

Two CD models were used to identify the molecular mechanism linking extracellular PT and endoplasmic reticulum (ER) stress in the IECs of predisposed individuals exposed to gliadin. These models were an in vitro model based on CaCo-2 cells and an ex vivo model based on our previously described gut ex vivo system (GEVS), both exposed to PT.

Our results clearly show that the interaction of gliadin peptides with the transmembrane CXCR3 receptor on IECs leads to a rapid induction of PLC activity that generates IP3 molecules. This second messenger binds to the IP3R located in ER membranes, resulting in calcium efflux from the organelle.

The PT-dependent ER stress observed in the IECs of CD patients results from the excessive release of calcium from the ER. Importantly, inhibition of this signaling pathway abrogates ER stress, which in turn attenuates downstream signs of CD, such as TG2 expression and gut permeability dysregulation, as well as inhibits inflammation.

Seneca Valley virus (SVV), also known as Senecavirus A, a porcine pathogen that causes vesicular diseases, is prevalent in pig herds worldwide. SVV infection induces endoplasmic reticulum (ER) stress in PK-15 and BHK-21 cells, accompanied by activation of the protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and activating transcription factor 6 (ATF6) pathways, which in turn facilitates SVV replication. ER stress is associated with the regulation of Ca2+ homeostasis and mitochondrial apoptosis. However, the precise role of Ca2+ in SVV-induced apoptosis remains unclear. In this study, western blotting, flow cytometry, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) detection revealed that either ER stress or the PERK pathway is involved in the apoptosis of SVV-infected cells treated with specific inhibitors. Furthermore, SVV-mediated ER stress markedly contributed to the transfer of Ca2+ from the ER to mitochondria. The subsequent increase in mitochondrial Ca2+ content was accompanied by an increased number of ER membranes near the mitochondria. Finally, the inhibition of mitochondrial Ca2+ overload, ER stress, and the PERK pathway substantially attenuated SVV-mediated mitochondrial dysfunction, as evidenced by analyzing mitochondrial membrane potential (MMP), mitochondrial permeability transition poremPTP, reactive oxygen speciesROS, and adenosine 5'-triphosphate ATP, and the levels of mitochondrial apoptosis. These findings demonstrate that SVV induces mitochondrial apoptosis, which is dependent on ER stress-mediated transmission of Ca2+ from the ER to the mitochondria.

Viruses have developed multiple mechanisms to facilitate their proliferation or persistence through manipulating various organelles in cells. Seneca Valley virus (SVV), as a novel emerging pathogen associated with vesicular disease, is clinically and economically important infections that affect farm animals. Previously, we had confirmed that SVV-induced endoplasmic reticulum (ER) stress benefited for viral replication. Ca2+, as an intracellular signaling messenger mainly stored in the ER, is regulated by ER stress and then involved in apoptosis. However, the precise mechanism that Ca2+ transfer induced by SVV infection triggered apoptosis remained unclear. Here, we found that SVV infection triggered the Ca2+ transform from ER to mitochondria, resulting in mitochondrial dysfunction, and finally induced mitochondrial apoptosis. Our study shed light on a novel mechanism revealing how ER stress manipulates Ca2+ homeostasis to induce mitochondrial apoptosis and regulate viral proliferation.

Thiram, a broadly used dithiocarbamate fungicide, exaggerates endoplasmic reticulum (ER) stress and interferes with mitochondrial function, thus disrupting cellular homeostasis. Here, we intend to identify the molecular actions of thiram at the mitochondrial-associated ER membranes (MAMs) that lead to the induction of ER stress and mitochondrial calcium overload in both liver and bone tissues. Taken together, we show that thiram-induced remodelling of MAMs leads to huge ER stress and calcium dysregulation. Histological and immunohistochemical examinations revealed that thiram-induced hyperactivation of IP3R1 mediated the release of endoplasmic reticulum calcium, but mitochondrial calcium uptake was mediated by voltage-dependent anion channels VDAC1. This stress response was characterized by increased glucose regulated protein 78 (GRP78) expression in the liver and tibial growth plates (GP). In this respect, a new liver-bone axis was delineated for thiram-induced ER stress. More interestingly, the activation of NLRP3 inflammasome was very striking in tibial growth plates but not in liver tissues. Hence, the results highlight the systemic effects of thiram by identifying a critical metabolic junction that might play a role in metabolic disorders such as tibial dyschondroplasia and related bone disorders, e.g., osteoarthritis and osteoporosis.

The success of BH3 mimetics in hematological malignancies has spurred interest in their application in solid tumors. We examined the expression of the BCL-2 family of molecules in NPC tumors and cell lines and explored the anticancer efficacy of BH3 mimetics in vitro.

Immunohistochemistry for BCL-2, MCL-1, BCL-xL, and transcriptomic analyses was conducted on NPC tumors. The efficacy of ABT-199, S63845, and ABT-737 were examined as monotherapy and in combination with cisplatin in NPC cell lines. RNA sequencing was performed to identify up and downregulated pathways in sensitive cell lines.

One hundred and forty-nine EBV-positive NPC and 15 EBV-negative NPC were identified. Expression of BCL-2 was more frequent in EBV-positive NPC. BCL-2, MCL-1, and BCL-xL expression was not prognostic for overall survival. Marked sensitivity was seen with the combination of S63845 and cisplatin in NPC43.

Our study demonstrates the therapeutic potential of combining cisplatin and S63845, which warrants further investigation.

The endoplasmic reticulum (ER) is a crucial cellular organelle involved in protein synthesis, folding, modification, and transport. Exposure to internal and external stressors can induce endoplasmic reticulum stress (ERS), leading to abnormal protein folding and ER malfunction. This stress can disrupt lipid synthesis, metabolism, and transport processes. Fatty acid oxidation is the primary energy source for the renal system. When energy intake exceeds the storage capacity of adipose tissue, lipids accumulate abnormally in non-adipose tissues, including kidneys, liver, and pancreas. Lipids accumulate in the kidneys of nearly all cell types, including thylakoid membranous, pedunculated, and proximal renal tubular epithelial cells. Intracellular free fatty acids can significantly disrupt renal lipid metabolism, contributing to ischemia-reperfusion acute kidney injury, diabetic nephropathy, renal fibrosis, and lupus nephritis. Consequently, this study delineated the primary signaling pathways and mechanisms of the ERS-induced unfolded protein response, explored the mechanistic link between ERS and lipid metabolism, and elucidated its role in renal lipid metabolism. This study aimed to offer new perspectives on managing and treating renal disorders.

Dolutegravir (DTG)-based antiretroviral therapy is the contemporary first-line therapy to treat HIV infection. Despite its efficacy, mounting evidence has suggested a higher risk of neuropsychiatric adverse effect (NPAE) associated with DTG use, with a limited understanding of the underlying mechanisms. Our laboratory has previously reported a toxic effect of DTG but not bictegravir (BTG) in disrupting the blood-brain barrier (BBB) integrity. The current study aimed to investigate the underlying mechanism of DTG toxicity. Primary cultures of mouse brain microvascular endothelial cells were treated with DTG and BTG at therapeutically relevant concentrations. RNA sequencing, qPCR, western blot analysis, and cell stress assays (Ca2+ flux, H2DCFDA, TMRE, MTT) were applied to assess the results. The gene ontology (GO) analysis revealed an enriched transcriptome signature of endoplasmic reticulum (ER) stress following DTG treatment. We demonstrated that therapeutic concentrations of DTG but not BTG activated the ER stress sensor proteins (PERK, IRE1, p-IRE1) and downstream ER stress markers (eIF2α, p-eIF2α, Hspa5, Atf4, Ddit3, Ppp1r15a, Xbp1, spliced-Xbp1). In addition, DTG treatment resulted in a transient Ca2+ flux, an aberrant mitochondrial membrane potential, and a significant increase in reactive oxygen species in treated cells. Furthermore, we found that prior treatment with ER sensor or ER stress inhibitors significantly mitigated the DTG-induced downregulation of tight junction proteins (Zo-1, Ocln, Cldn5) and elevation of pro-inflammatory cytokines and chemokines (Il6, Il23a, Il12b, Cxcl1, Cxcl2). The current study provides valuable insights into DTG-mediated cellular toxicity mechanisms, which may serve as a potential explanation for DTG-associated NPAEs in the clinic.

Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme for redox reactions and regulates cellular catabolic pathways. An intertwined relationship exists between NAD+ and mitochondria, with consequences for mitochondrial function. Dysregulation in NAD+ homeostasis can lead to impaired energetics and increased oxidative stress, contributing to the pathogenesis of cardiometabolic diseases. In this review, we explore how disruptions in NAD+ homeostasis impact mitochondrial function in various cardiometabolic diseases. We discuss emerging studies demonstrating that enhancing NAD+ synthesis or inhibiting its consumption can ameliorate complications of this family of pathological conditions. Additionally, we highlight the potential role and therapeutic promise of mitochondrial NAD+ transporters in regulating cellular and mitochondrial NAD+ homeostasis.

GRP78 (Glucose-related protein 78, BiP/HSPA5) is commonly overexpressed in cancer cells. Acting as an activator of endoplasmic reticulum stress, GRP78 is involved in the resistance of cancer cells to injury. Current evidence suggests that GRP78 plays a significant role in the radiotherapy resistance and chemotherapy resistance of cancers, which is accomplished through a variety of complex pathways. These include the promotion of tumor stemness, inhibition of apoptosis, regulation of autophagy, maintenance of tumor microenvironment homeostasis, protection of dormant cells, evasion of senescence, counteraction of autoantibodies against GRP78, facilitation of DNA damage repair, suppression of ferroptosis, and modulation of metabolic reprogramming in tumor cells. Importantly, chemoradiotherapy resistance in cancers are the main reasons for treatment failure in patients, severely affecting their survival. Investigating the mechanisms of GRP78 in tumor therapeutic resistance is essential. In this article, we review the mechanisms by which GRP78 mediates cell survival and chemoradiotherapy resistance in cancers and provide an overview of clinical trials targeting GRP78 therapy.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition marked by excessive lipid accumulation in hepatic tissue. This disorder can lead to a range of pathological outcomes, including metabolic dysfunction-associated steatohepatitis (MASH) and cirrhosis. Despite extensive research, the molecular mechanisms driving MASLD initiation and progression remain incompletely understood. Oxidative stress and lipid peroxidation are pivotal in the "multiple parallel hit model", contributing to hepatic cell death and tissue damage. Gut microbiota plays a substantial role in modulating hepatic oxidative stress through multiple pathways: impairing the intestinal barrier, which results in bacterial translocation and chronic hepatic inflammation; modifying bile acid structure, which impacts signaling cascades involved in lipidic metabolism; influencing hepatocytes' ferroptosis, a form of programmed cell death; regulating trimethylamine N-oxide (TMAO) metabolism; and activating platelet function, both recently identified as pathogenetic factors in MASH progression. Moreover, various exogenous factors impact gut microbiota and its involvement in MASLD-related oxidative stress, such as air pollution, physical activity, cigarette smoke, alcohol, and dietary patterns. This manuscript aims to provide a state-of-the-art overview focused on the intricate interplay between gut microbiota, lipid peroxidation, and MASLD pathogenesis, offering insights into potential strategies to prevent disease progression and its associated complications.

Oocytes and early embryos are exposed to many uncontrollable factors that trigger endoplasmic reticulum (ER) stress during in vitro culture. Prevention of ER stress is an effective way to improve the oocyte maturation rate and oocyte quality. Increasing evidence suggests that dietary intake of sufficient n-3 polyunsaturated fatty acids (PUFAs) is associated with health benefits, particularly in the domain of female reproductive health. We found that supplementation of eicosatrienoic acid (ETA) during in vitro maturation (IVM) of oocyte significantly downregulated ER stress-related genes. Mitochondria-associated membranes (MAMs) are communications areas between the ER and mitochondria. Inositol 1,4,5-trisphosphate receptor (IP3R) is a key calcium channels in MAMs and, participates in the regulation of many cellular functions. Notably, the MAM area was significantly decreased in ETA-treated oocytes. CDGSH iron sulfur domain 2 (CISD2) is presents in MAMs, but its role in oocytes is unknown. ETA treatment significantly increased CISD2 expression, and siRNA-mediated knockdown of CISD2 blocked the inhibitory effect of ETA on IP3R. Transcriptomic sequencing and immunoprecipitation experiments showed that ETA treatment significantly decreased expression of the E3 ubiquitin ligase PRKN. PRKN induced ubiquitination and degradation of CISD2, indicating that the PRKN-mediated ubiquitin-proteasome system regulates CISD2. In conclusion, our study reveals the mechanism by which ETA supplementation during IVM alleviates mitochondrial calcium overload under ER stress conditions by decreasing PRKN-mediated ubiquitination of CISD2 and facilitating inhibition of IP3R by CISD2/BCL-2. This improves oocyte quality and subsequent embryo developmental competence prior to implantation.

Acute kidney injury (AKI) induced by renal ischemia-reperfusion injury (IRI) has a high morbidity and mortality, representing a worldwide problem. The kidney is an essential organ of metabolism that has high blood perfusion and is the second most mitochondria-rich organ after the heart because of the high ATP demands of its essential functions of nutrient reabsorption, acid-base and electrolyte balance, and hemodynamics. Thus, these energy-intensive cells are particularly vulnerable to mitochondrial dysfunction. As the bulk of glomerular ultrafiltrate reabsorption by proximal tubules occurs via active transport, the mitochondria of proximal tubules must be equipped for detecting and responding to fluctuations in energy availability to guarantee efficient basal metabolism. Any insults to mitochondrial quality control mechanisms may lead to biological disruption, blocking the clearance of damaged mitochondria and resulting in morphological change and tissue dysfunction. Extensive research has shown that mitochondria have pivotal roles in acute kidney disease, so in this article, we discuss the role of mitochondria, their dynamics and mitophagy in renal ischemia-reperfusion injury.

Thapsigargin, a sesquiterpene lactone derived from Thapsia garganica L., has demonstrated mixed potential as an anticancer agent due to its potent ability to disrupt calcium signaling and induce apoptosis. This review evaluates the chemopreventive and chemotherapeutic potential of thapsigargin, focusing on its molecular mechanisms and toxicity. An extensive literature review of studies published since 2015 was conducted using databases such as PubMed/MedLine and Science Direct. Findings indicate that thapsigargin's primary mechanism is the inhibition of sarco/endoplasmic reticulum calcium ATPase, leading to endoplasmic reticulum stress and cell death in various cancer types. Despite these effects, thapsigargin's non-specific cytotoxicity results in significant side effects, including organ damage and histamine-related reactions. Recent advances in targeted delivery, especially with the prodrug mipsagargin, initially suggested promise in minimizing these toxicities by selectively activating in cancer cells expressing prostate-specific membrane antigen (PSMA). However, the completion of clinical trials with no ongoing studies suggests that the viability of mipsagargin and other prodrugs remains uncertain, especially in light of the toxicities observed. While thapsigargin and its derivatives present a potential pathway in cancer treatment, their future role in oncology requires careful re-evaluation.

Fetal programming by exposure to high-energy diets increases the susceptibility to type 2 diabetes mellitus (T2DM2) in the offspring. Glucose imbalance during fetal programming might be associated to still unknown selective lipid species and their characterization might be beneficial for T2DM diagnosis and treatment. We aim to characterize the effect of the lipid specie, C24:0 ceramide, on glucose imbalance and metabolic impairment in cellular and murine models. A lipidomic analysis identified accumulation of C24:0 ceramide in plasma of offspring rats exposed to high-energy diets during fetal programing, as well as in obese-T2DM subjects. In vitro experiments in 3T3L-1, hMSC and HUH7 cells and in in vivo models of Wistar rats and C57BL/6 mice demonstrated that C24:0 ceramide disrupted glucose balance, and differentiation and lipid accumulation in adipocytes, whereas promoted liver steatosis. Mechanistically, C24:0 ceramide impaired mitochondrial fatty acid oxidation in adipocytes and hepatic cells, tentatively by favoring reactive oxygen species accumulation and calcium overload in the mitochondria; and also, activates endoplasmic reticulum (ER) stress in hepatocytes. We propose that C24:0 ceramide accumulation in the offspring followed a prenatal diet exposure, impair lipid allocation into adipocytes and enhances liver steatosis associated to mitochondrial dysfunction and ER stress, leading to glucose imbalance.

Endoplasmic reticulum (ER) stress interferes with developmental processes in oocyte maturation and embryo development. Invitro growth (IVG) is associated with low developmental competence, and ER stress during IVG culture may play a role. Therefore, this study aimed to examine the effect of tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor, on the IVG of bovine oocytes to understand the role of ER stress. Oocyte-granulosa cell complexes (OGCs) were collected from early antral follicles (1.5-1.8 mm) and allowed to grow in vitro for 5 days at 38.5 °C in a humidified atmosphere containing 5 % CO2. Basic growth culture medium was supplemented with TUDCA at various concentrations (0, 50, 100, 250, and 500 μM). After IVG, oocyte diameters were similar among groups, but the antrum formation rate tended to be higher in the TUDCA 100 μM group. The mRNA expression levels of ER stress-associated genes (PERK, ATF6, ATF4, CHOP, BAX, IRE1, and XBP1) in OGCs were downregulated in the TUDCA 100 μM group than those in the control group. Moreover, the TUDCA 100 μM group exhibited reduced ROS production with higher GSH levels and improved in vitro-grown oocyte maturation compared with those in the control group. In contrast, no difference in the developmental competence of embryos following invitro fertilization was observed between the control and TUDCA 100 μM groups. These results indicate that ER stress could impair IVG and subsequent maturation rate of bovine oocytes, and TUDCA could alleviate these detrimental effects. These outcomes might improve the quality of oocytes in IVG culture in assisted reproductive technology.

Imidacloprid (IMI), an insecticide from the neonicotinoid group widely used in agriculture, has drawn attention due to its potential harmful effects on non-target species, including bird populations. In the present work, we investigated the effect of IMI on avian semen by in vitro exposure of rooster spermatozoa to this pesticide. The semen was collected twice a week. Samples collected on one day were pooled and incubated with the following IMI concentrations: 0 mM, 0.5 mM, 5 mM, 10 mM, and 50 mM at 36°C for 3 h. Comprehensive semen analysis was carried out after 1 h and 3 h of incubation, evaluating sperm motility parameters with the CASA system and using flow cytometry to assess membrane integrity, mitochondrial activity, acrosome integrity, chromatin structure, intracellular calcium level and apoptosis markers such as: early apoptosis and caspase activation and lipid peroxidation. The results of the first experiment suggest that low concentrations of IMI have a different effect on sperm motility compared to higher concentrations. In IMI samples, we also observed a lower percentage of cells with a high level of calcium ions compared to the control, and a lower level of lipid peroxidation. We concluded that IMI may act as a blocker of calcium channels, preventing the influx of these ions into the cell. To confirm this mechanism, we conducted a second experiment with calcium channel blockers: SNX 325, MRS-1845, and Nifedipine. The results of this experiment confirmed that the mechanism of action of IMI largely relies on the blockade of calcium channels in rooster sperm. Blocking the influx of calcium ions into the cell prevents the formation of Ca²⁺-dependent pores, thereby preventing an increase in cell membrane permeability, ultimately blocking early apoptosis and lipid peroxidation in chicken spermatozoa.

Bisphenol A (BPA) is widely used in plastic and paper products, and its exposure can occur through skin contact or oral ingestion. The hazardous effects of BPA absorbed through the skin may be more severe; however, few studies have investigated the skin toxicity of BPA. This study investigated the effects of BPA on human epidermal keratinocyte cell lines, which is relevant for skin exposure. BPA treatment reduced cell viability in a time- and concentration-dependent manner and elevated oxidative and endoplasmic reticulum (ER) stress. N-acetylcysteine (NAC), an oxidative stress inhibitor, reduced BPA-induced reactive oxygen species (ROS) levels. However, only 10% of the decreased cell viability was restored at the highest NAC concentration. Treatment with tauroursodeoxycholic acid (TUDCA), which is an ER stress inhibitor, effectively countered the increase in ER stress-related proteins induced by BPA. Moreover, TUDCA treatment led to a reduction in oxidative stress, as demonstrated by the decrease in ROS levels, maintenance of mitochondrial membrane potential, and modulation of stress signaling proteins. Consequently, TUDCA significantly improved BPA-induced cytotoxicity in a concentration-dependent manner. Notably, combined treatment using TUDCA and NAC further reduced the BPA-induced ROS levels; however, no significant difference in cell viability was observed compared with that for TUDCA treatment alone. These findings indicated that the oxidative stress observed following BPA exposure was exacerbated by ER stress. Moreover, the principal factor driving BPA-induced cytotoxicity was indeed ER stress, which has potential implications for developing therapeutic strategies for diseases associated with similar stress responses.

NAFLD is a condition that develops when the liver accumulates excess fat without alcohol consumption. This chronic liver ailment progresses along with insulin resistant and is typically not diagnosed until the patients have cirrhosis. Nuclear hormone receptor superfamily PPARs are essential for metabolism of fatty acids and glucose. In liver, lipid metabolism is regulated by nuclear receptors and PPARα, and PPARβ/δ encourages fatty acid β-oxidation. PPAR-γ, an energy-balanced receptor is a crucial regulator in NAFLD. The partial activation of PPAR-γ could lead to increased level of adiponectin and insulin sensitivity, thus improved NAFLD. Because of less side effects, natural compounds are emerged as potential therapeutic agents for NAFLD by PPARγ agonists. Although the results from preclinical studies are promising, further research is needed to determine the potential dosing and efficacy of mentioned compounds in human subjects. In this review, we summarize the effect of natural PPARγ agonist in the NAFLD.

ATP2B1 is a known regulator of calcium (Ca2+) cellular export and homeostasis. Diminished levels of intracellular Ca2+ content have been suggested to impair SARS-CoV-2 replication. Here, we demonstrate that a nontoxic caloxin-derivative compound (PI-7) reduces intracellular Ca2+ levels and impairs SARS-CoV-2 infection. Furthermore, a rare homozygous intronic variant of ATP2B1 is shown to be associated with the severity of COVID-19. The mechanism of action during SARS-CoV-2 infection involves the PI3K/Akt signaling pathway activation, inactivation of FOXO3 transcription factor function, and subsequent transcriptional inhibition of the membrane and reticulum Ca2+ pumps ATP2B1 and ATP2A1, respectively. The pharmacological action of compound PI-7 on sustaining both ATP2B1 and ATP2A1 expression reduces the intracellular cytoplasmic Ca2+ pool and thus negatively influences SARS-CoV-2 replication and propagation. As compound PI-7 lacks toxicity in vitro, its prophylactic use as a therapeutic agent against COVID-19 is envisioned here.

Malignant Pleural Mesothelioma (MPM) is a rare malignancy with a poor prognosis. Current therapies are unsatisfactory and novel cures are urgently needed. In a previous drug screening, we identified thonzonium bromide (TB) as one of the most active compounds against MPM cells. Since the biological effects of TB are poorly known, in this work we departed from some hints of previous studies and investigated several hypotheses. Moreover, we evaluated the efficacy of TB in an in vivo xenograft rodent model.

In vitro assessment was made on five MPM (Mero-14, Mero-25, Ren, NCI-H28, MSTO-211H) and one SV40-immortalized mesothelial cell line (MeT-5A). We evaluated TB ability to affect proliferation, apoptosis, mitochondrial functions and metabolism, and the mevalonate pathway. In vivo assay was carried out on MPM-xenograft NOD-SCID mice (4 mg/kg delivered intraperitoneally, twice a week for 4 weeks) and the overall survival was analysed with Kaplan-Meier curves.

After TB treatment, we observed the suppression of ERK 1/2 phosphorylation, the increase of BAX expression and p38 phosphorylation. TB affected Ca2+ homeostasis in both mitochondrial and cytosolic compartments, it regulated the mitochondrial functioning, respiration, and ATP production as well as the mevalonate pathway. The in vivo study showed an increased overall survival for TB treated group vs. vehicle control group (P = 0.0076).

Both in vitro and in vivo results confirmed the effect of TB on MPM and unravelled novel targets with translational potential.

Gain-of-function mutation in the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) catalytic subunit alpha gene (PIK3CA) is a significant factor in head and neck cancer (HNC). Patients with HNC harboring PIK3CA mutations receive therapeutic benefits from the use of non-steroidal anti-inflammatory drugs (NSAIDs). However, the molecular mechanisms underlying these effects remain unknown. Here, we examined the Detroit562 and FaDu cell lines as HNC models with and without a hyperactive PIK3CA mutation (H1047R), respectively, regarding their possible distinct responses to the NSAIDs celecoxib and sulindac sulfide (SUS). Detroit562 cells exhibited relatively high PI3K/Akt pathway-dependent cyclooxygenase-2 (COX-2) expression, associated with cell proliferation. Celecoxib treatment restricted cell proliferation and upregulated endoplasmic reticulum (ER) stress-related markers, including GRP78, C/EBP-homologous protein, activating transcription factor 4, death receptor 5, and reactive oxygen species (ROS). These effects were much stronger in Detroit562 cells than in FaDu cells and were largely COX-2-independent. SUS treatment yielded similar results. Salubrinal (an ER stress inhibitor) and N-acetyl-L-cysteine (a ROS scavenger) prevented NSAID-induced ROS generation and ER stress, respectively, indicating crosstalk between ER and oxidative stress. In addition, celecoxib and/or SUS elevated cleaved caspase-3 levels, Bcl-2-associated X protein/Bcl-2-interacting mediator of cell death expression, and mitochondrial damage, which was more pronounced in Detroit562 than in FaDu cells. Salubrinal and N-acetyl-L-cysteine attenuated celecoxib-induced mitochondrial dysfunction. Collectively, our results suggest that celecoxib and SUS efficiently suppress activating PIK3CA mutation-harboring HNC progression by inducing ER and oxidative stress and mitochondrial dysfunction, leading to apoptotic cell death, further supporting NSAID treatment as a useful strategy for oncogenic PIK3CA-mutated HNC therapy.

Hypertension is a principal risk factor for cardiovascular morbidity and mortality, with its severity exacerbated by high sodium intake, particularly in individuals with salt-sensitive blood pressure. However, the mechanisms underlying hypertension and salt sensitivity are only partly understood. Herein, we review potential interactions in hypertension pathophysiology involving the immune system, endoplasmic reticulum (ER) stress, the unfolded protein response (UPR), and proteostasis pathways; identify knowledge gaps; and discuss future directions.

Recent advancements by our research group and others reveal interactions within and between adaptive and innate immune responses in hypertension pathophysiology. The salt-immune-hypertension axis is further supported by the discovery of the role of dendritic cells in hypertension, marked by isolevuglandin (IsoLG) formation. Alongside these broadened understandings of immune-mediated salt sensitivity, the contributions of T cells to hypertension have been recently challenged by groups whose findings did not support increased resistance of Rag-1-deficient mice to Ang II infusion. Hypertension has also been linked to ER stress and the UPR. Notably, a holistic approach is needed because the UPR engages in crosstalk with autophagy, the ubiquitin proteasome, and other proteostasis pathways, that may all involve hypertension. There is a critical need for studies to establish cause and effect relationships between ER stress and the UPR in hypertension pathophysiology in humans and to determine whether the immune system and ER stress function mainly to exacerbate or initiate hypertension and target organ injury. This review of recent studies proposes new avenues for future research for targeted therapeutic interventions.

Non-small cell lung cancer (NSCLC) remains at the forefront of new cancer cases, and there is an urgent need to find new treatments or improve the efficacy of existing therapies. In addition to the application in the field of cerebrovascular diseases, recent studies have revealed that tanshinone IIA (Tan IIA) has anticancer activity in a variety of cancers.

To investigate the potential anticancer mechanism of Tan IIA and its impact on immunotherapy in NSCLC.

Cytotoxicity and colony formation assays were used to detect the Tan IIA inhibitory effect on NSCLC cells. This research clarified the mechanisms of Tan IIA in anti-tumor and programmed death-ligand 1 (PD-L1) regulation by using flow cytometry, transient transfection, western blotting and immunohistochemistry (IHC) methods. Besides, IHC was also used to analyze the nuclear factor of activated T cells 1 (NFAT2) expression in NSCLC clinical samples. Two animal models including xenograft mouse model and Lewis lung cancer model were used for evaluating tumor suppressive efficacy of Tan IIA. We also tested the efficacy of Tan IIA combined with programmed cell death protein 1 (PD-1) inhibitors in Lewis lung cancer model.

Tan IIA exhibited good NSCLC inhibitory effect which was accompanied by endoplasmic reticulum (ER) stress response and increasing Ca2+ levels. Moreover, Tan IIA could suppress the NFAT2/ Myc proto oncogene protein (c-Myc) signaling, and it also was able to control the Jun Proto-Oncogene(c-Jun)/PD-L1 axis in NSCLC cells through the c-Jun N-terminal kinase (JNK) pathway. High NFAT2 levels were potential factors for poor prognosis in NSCLC patients. Finally, animal experiments data showed a stronger immune activation phenotype, when we performed treatment of Tan IIA combined with PD-1 monoclonal antibody.

The findings of our research suggested a novel mechanism for Tan IIA to inhibit NSCLC, which could exert anti-cancer effects through the JNK/NFAT2/c-Myc pathway. Furthermore, Tan IIA could regulate tumor PD-L1 levels and has the potential to improve the efficacy of PD-1 inhibitors.

In Type 1 and Type 2 diabetes, pancreatic β-cell survival and function are impaired. Additional etiologies of diabetes include dysfunction in insulin-sensing hepatic, muscle, and adipose tissues as well as immune cells. An important determinant of metabolic health across these various tissues is mitochondria function and structure. This review focuses on the role of mitochondria in diabetes pathogenesis, with a specific emphasis on pancreatic β-cells. These dynamic organelles are obligate for β-cell survival, function, replication, insulin production, and control over insulin release. Therefore, it is not surprising that mitochondria are severely defective in diabetic contexts. Mitochondrial dysfunction poses challenges to assess in cause-effect studies, prompting us to assemble and deliberate the evidence for mitochondria dysfunction as a cause or consequence of diabetes. Understanding the precise molecular mechanisms underlying mitochondrial dysfunction in diabetes and identifying therapeutic strategies to restore mitochondrial homeostasis and enhance β-cell function are active and expanding areas of research. In summary, this review examines the multidimensional role of mitochondria in diabetes, focusing on pancreatic β-cells and highlighting the significance of mitochondrial metabolism, bioenergetics, calcium, dynamics, and mitophagy in the pathophysiology of diabetes. We describe the effects of diabetes-related gluco/lipotoxic, oxidative and inflammation stress on β-cell mitochondria, as well as the role played by mitochondria on the pathologic outcomes of these stress paradigms. By examining these aspects, we provide updated insights and highlight areas where further research is required for a deeper molecular understanding of the role of mitochondria in β-cells and diabetes.

The present study aims to evaluate the protective effect of Crataegus azarolus berries decoction extract (CAB-DE) against acetic acid-induced ulcerative colitis as well as the mechanisms implicated in such protection. Adult male Wistar rats were separated into seven groups: Control (H2O), acetic acid (AA), AA + various doses of CAB-DE (100, 200, and 400 mg/kg, b.w.,p.o.), and AA + sulfasalazine (100 mg/kg, b.w.,p.o.) or gallic acid (50 mg/kg, b.w.,p.o.) during 10 days. All rats were kept fasting overnight and ulcerative colitis was induced by rectal infusion of AA (300 mg kg-1, b.w.) (3%, v/v, 5 mL kg-1 b.w), for 30 s. The colon was rapidly excised and macroscopically examined to measure ulcerated surfaces and the ulcer index. In vitro, we found that CAB-DE exhibited a high antioxidant activity against DPPH radical (IC50 = 164.17 ± 4.78 μg/mL). In vivo, pretreatment with CAB-DE significantly protected the colonic mucosa against AA-induced damage by stimulating mucus secretion, reducing ulcer index as well as histopathological changes. Also, CAB-DE limited the oxidative status induced by AA in the colonic mucosa, as assessed by MDA and H2O2 increased levels and the depletion of both enzymatic activities and non-enzymatic levels. In addition, AA intoxication increased iron and calcium levels in colonic mucosa and plasma, while CAB-DE pretreatment regulated all intracellular mediators deregulation and significantly reduced inflammatory markers such as CRP (1.175 ± .04 ─ .734 ± .06 μg/dl) and ALP (161.53 ± 5.02 ─ 98.60 ± 4.21 UI/L) levels. We suggest that CAB-DE protected against AA-induced ulcerative colitis due in part to its antioxidant and anti-inflammatory properties.

An extensive network of chaperones and folding factors is responsible for maintaining a functional proteome, which is the basis for cellular life. The underlying proteostatic mechanisms are not isolated within organelles, rather they are connected over organellar borders via signalling processes or direct association via contact sites. This review aims to provide a conceptual understanding of proteostatic mechanisms across organelle borders, not focussing on individual organelles. This discussion highlights the precision of these finely tuned systems, emphasising the complicated balance between cellular protection and adaptation to stress. In this review, we discuss widely accepted aspects while shedding light on newly discovered perspectives.

Cinnamic acid, ferulic acid, and the flavonoids quercetin and taxifolin (dihydroquercetin) are naturally occurring compounds found in plants. They are often referred to as polyphenols and are known, among others, for their pharmacological effects supporting health through the inhibition of aging processes and oxidative stress. To improve their bioavailability, pharmacological activities, and safety, the creation of novel flavonoid-phenolic acid hybrids is an area of active research. Previous work showed that such hybridization products of phenolic acids and flavonoids enhanced the resilience of neuronal cells against oxidative stress in vitro, and attenuated cognitive impairment in a mouse model of Alzheimer's disease (AD) in vivo. Notably, the therapeutic effects of the hybrid compounds we obtained were more pronounced than the protective activities of the respective individual components. The underlying mechanisms mediated by the flavonoid-phenolic acid hybrids, however, remained unclear and may differ from the signaling pathways activated by the originating structures of the respective individual phenolic acids or flavonoids. In this study, we characterized the effects of four previously described potent flavonoid-phenolic acid hybrids in models of oxidative cell death through ferroptosis. Ferroptosis is a type of iron-dependent regulated cell death characterized by lipid peroxidation and mitochondrial ROS generation and has been linked to neurodegenerative conditions. In models of ferroptosis induced by erastin or RSL3, we analyzed mitochondrial (lipid) peroxidation, mitochondrial membrane integrity, and Ca2+ regulation. Our results demonstrate the strong protective effects of the hybrid compounds against ROS formation in the cytosol and mitochondria. Importantly, these protective effects against ferroptosis were not mediated by radical scavenging activities of the phenolic hybrid compounds but through inhibition of mitochondrial complex I activity and reduced mitochondrial respiration. Our data highlight the effects of flavonoid-phenolic acid hybrids on mitochondrial metabolism and further important mitochondrial parameters that collectively determine the health and functionality of mitochondria with a high impact on the integrity and survival of the neuronal cells.

Immunogenic cell death (ICD) has emerged as a promising approach to cancer immunotherapy. During ICD, cancer cell death and the release of damage-associated molecular pattern (DAMP) signals occur simultaneously. Increased production of reactive oxygen species (ROS) and severe endoplasmic reticulum stress are necessary for enhanced ICD. Furthermore, the levels of ROS and reduced glutathione (GSH) are involved in various cell death mechanisms. The thiazole ring structure has gained considerable interest as a functional moiety for anticancer agents. This study designed and synthesized a positively charged cell-penetrating polypeptide with a thiazole functional moiety (NS). The NS internalizes into the cancer cells through direct penetration and endo-lysosomal escape. The NS induces mitochondrial depolarization and ER stress in a concentration-dependent manner, leading to a significant ROS production and GSH depletion. Consequently, the ICD of cancer cells is activated, resulting in the release of DAMP signals. Furthermore, NS causes a shift in the cell death pathway from apoptosis to necroptosis as the concentration increases. In this study, we confirmed the possibility of NS as a promising ICD inducer that can be used while varying the concentration according to the cancer type.

Mitochondria are sensitive organelles that sense intrinsic and extrinsic stressors and maintain cellular physiological functions through the dynamic homeostasis of mitochondrial fusion and fission. Numerous pathological processes are associated with mitochondrial fusion and fission disorders. However, the molecular mechanism by which stress induces cardiac pathophysiological changes through destabilising mitochondrial fusion and fission is unclear. Therefore, this study aimed to investigate whether the endoplasmic reticulum stress signalling pathway initiated by the turbulence of mitochondrial fusion and fission under stressful circumstances is involved in cardiomyocyte damage. Based on the successful establishment of the classical stress rat model of restraint plus ice water swimming, we measured the content of serum lactate dehydrogenase. We used haematoxylin-eosin staining, special histochemical staining, RT-qPCR and western blotting to clarify the cardiac pathology, ultrastructural changes and expression patterns of mitochondrial fusion and fission marker proteins and endoplasmic reticulum stress signalling pathway proteins. The results indicated that mitochondrial fusion and fission markers and proteins of the endoplasmic reticulum stress JNK signalling pathway showed significant abnormal dynamic changes with the prolongation of stress, and stabilisation of mitochondrial fusion and fission using Mdivi-1 could effectively improve these abnormal expressions and ameliorate cardiomyocyte injury. These findings suggest that stress could contribute to pathological cardiac injury, closely linked to the endoplasmic reticulum stress JNK signalling pathway induced by mitochondrial fusion and fission turbulence.

The endoplasmic reticulum (ER) stores large amounts of calcium (Ca2+), and the controlled release of ER Ca2+ regulates a myriad of cellular functions. Although altered ER Ca2+ homeostasis is known to induce ER stress, the mechanisms by which ER Ca2+ imbalance activate ER stress pathways are poorly understood. Stromal-interacting molecules STIM1 and STIM2 are two structurally homologous ER-resident Ca2+ sensors that synergistically regulate Ca2+ influx into the cytosol through Orai Ca2+ channels for subsequent signaling to transcription and ER Ca2+ refilling. Here, we demonstrate that reduced STIM2, but not STIM1, in colorectal cancer (CRC) is associated with poor patient prognosis. Loss of STIM2 causes SERCA2-dependent increase in ER Ca2+, increased protein translation and transcriptional and metabolic rewiring supporting increased tumor size, invasion, and metastasis. Mechanistically, STIM2 loss activates cMyc and the PERK/ATF4 branch of ER stress in an Orai-independent manner. Therefore, STIM2 and PERK/ATF4 could be exploited for prognosis or in targeted therapies to inhibit CRC tumor growth and metastasis.

Toxicant-induced injury is a significant global health issue. However, the mechanisms through which toxicants such as carbon tetrachloride, acetaminophen, dimethylformamide, cocaine, and morphine induce the death of multiple cell types and contribute to liver toxicity are highly complex. This phenomenon involves intricate signaling pathways in association with oxidative stress, inflammation, and activation of death receptors, which are closely linked to endoplasmic reticulum (ER) stress. ER stress initially triggers the unfolded protein response, which either promotes cell survival or causes cell death at later times, depending on the severity and duration of the stress. Thus, comprehending the molecular basis governing cell fate determination in the context of ER stress may provide key insights into the prevention and treatment of toxicant-induced injury. This review summarizes our current understanding of agents that trigger different forms of ER stress-mediated cell death, necroptosis, ferroptosis, pyroptosis, and apoptosis, and covers the underlying molecular basis of toxicant-induced ER stress, as well as potential target molecules.

Bisphenol A (BPA) is a chemical partially soluble in water and exists in a solid state. Its structural similarity with estrogen makes it an endocrine-disrupting chemical. BPA can disrupt signaling pathways at very low doses and may cause organellar stress. According to in vitro and in vivo studies, BPA interacts with various cell surface receptors to cause organellar stress, producing free radicals, cellular toxicity, structural changes, DNA damage, mitochondrial dysfunction, cytoskeleton remodeling, centriole duplication, and aberrant changes in several cell signaling pathways. The current review summarizes the impact of BPA exposure on the structural and functional aspects of subcellular components of cells such as the nucleus, mitochondria, endoplasmic reticulum, lysosome, ribosome, Golgi apparatus, and microtubules and its consequent impact on human health.