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1.
Biomed Res Int ; 2022: 7380324, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046439

RESUMO

Objective: To explore the function and mechanism of Sirt-1 in fluorine-induced liver injury. Method: Fluorosis rats were first established. The fluorine content, pathological structure, collagen fibers, and fibrosis in liver tissues were tested through the fluoride ion selective electrode method, H&E, Masson, and Sirius red staining; alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin 18 (IL-18), and tumor necrosis factor-α (TNF-α) levels in rat serum were also analyzed using ELISA kits. Then, the fluorosis cell model was built, which was also alleviated with NaF, Sirt-1 siRNAs, or endoplasmic reticulum stress (ERS) alleviator (4-PBA). CCK-8 also assessed cell proliferation; RT-qPCR or Western blots detect sirtuin-1 (Sirt-1), protein kinase R- (PKR-) like endoplasmic reticulum kinase (PERK), and endoplasmic reticulum stress (ERS) and apoptosis-related protein levels in liver tissue. Results: Our results uncovered that fluorine exposure could aggravate the pathological damage and fibrosis of rat liver tissues and increase indicators related to liver injury. And fluoride exposure also could downregulate Sirt-1 and upregulate ERS-related proteins (PERK, 78-kD glucose-regulated protein (GRP-78), and activating transcription factor 6 (ATF6)) and apoptosis-related protein (caspase-3 and C/EBP-homologous protein (CHOP)) in rat liver tissues. Besides, we proved that fluoride exposure could suppress proliferation and enhances ERS and apoptotic pathways in AML12 cells by downregulating Sirt-1. Moreover, we revealed that ERS alleviator (4-PBA) could induce proliferation and prevent ERS and apoptosis in fluorine-exposed AML12 cells. Conclusions: We suggested that fluorine exposure can induce hepatocyte ERS and apoptosis through downregulation of Sirt-1.


Assuntos
Estresse do Retículo Endoplasmático , Fluoretos , Animais , Apoptose , Proliferação de Células , Fibrose , Fluoretos/toxicidade , Flúor , Hepatócitos , Ratos , Sirtuína 1
2.
Ecotoxicol Environ Saf ; 241: 113803, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36068739

RESUMO

Chronic interstitial nephritis in agricultural communities (CINAC) is a severe and widespread disease that has been associated with environmental and occupational exposure to glyphosate and hard water. However, the potential underlying mechanisms remain incompletely understood. Melatonin is reported to exert protective effects on the kidney, but whether melatonin can attenuate renal tubular injury in mice exposed to glyphosate combined with hard water is unclear. Here, mice were treated with high doses and environmentally relevant doses of glyphosate (100 mg/kg·bw and 0.7 mg/L, respectively) and/or hard water (2500 mg/L CaCO3 and 250 mg/L Ca2+, respectively) via their drinking water for 12 weeks. We found that high-dose glyphosate or hard water treatment significantly increased the levels of biomarkers of renal damage, including ß2-microglobulin, neutrophil gelatinase-associated lipid carrier protein, and/or albumin, in the urine; these increased biomarker levels were correlated with obvious morphological changes, and all of these changes were also observed in animals exposed to environmentally relevant doses of glyphosate and/or high Ca2+ water. Melatonin (10 mg/kg·bw, intraperitoneal injection, daily for 12 weeks) administered concomitantly with high doses of glyphosate and hard water inhibited the glyphosate- and hard water-induced increases in the levels of kidney injury biomarkers and changes in morphology; this result was intriguing. Additionally, glyphosate combined with hard water at both high and environmentally relevant doses significantly upregulated the expression of the endoplasmic reticulum (ER) stress marker proteins Bip, ATF6, and PERK as well as the pyroptosis-related proteins (NLRP3 and caspase 1 signaling proteins) in renal tissues. Similarly, melatonin significantly attenuated the increased ER stress and pyroptosis induced by high doses of glyphosate and hard water. In summary, we conclude that exposure to glyphosate and hard water at both high doses and environmentally relevant doses causes renal dysfunction in mice, and this dysfunction can be attenuated by melatonin, possibly through the inhibition of ER stress and pyroptosis. Our results support the notion that melatonin may have therapeutic potential for the treatment of chronic kidney diseases.


Assuntos
Melatonina , Insuficiência Renal Crônica , Animais , Estresse do Retículo Endoplasmático , Glicina/análogos & derivados , Glicina/toxicidade , Melatonina/farmacologia , Camundongos
3.
World J Gastroenterol ; 28(26): 3201-3217, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-36051342

RESUMO

BACKGROUND: Endoplasmic reticulum (ER) stress contributes to the pathogenesis of chronic liver diseases, but how hepatocytes respond to ER stress has not been clarified. Alpha-fetoprotein (AFP) is secreted by hepatoma cells and elevated levels of serum AFP are associated with development of liver malignancies. AIM: To investigate whether and how AFP could regulate ER stress and hepatocyte injury. METHODS: The distribution of AFP and the degrees of ER stress in liver tissues and liver injury were characterized by histology, immunohistochemistry, and Western blot in biopsied human liver specimens, two mouse models of liver injury and a cellular model. The levels of AFP in sera and the supernatants of cultured cells were quantified by chemiluminescence. RESULTS: High levels of intracellular AFP were detected in liver tissues, particularly in the necrotic areas, from patients with chronic liver diseases and mice after carbon tetrachloride (CCl4) administration or induction of ER stress, but not from the controls. The induced intracellular AFP was accompanied by elevated activating transcription factor-6 (ATF6) expression and protein kinase R-like ER kinase (PERK) phosphorylation in mouse livers. ER stress induced AFP expression in LO2 cells and decreased their viability. ATF6, but not PERK, silencing mitigated the ER-stress-induced AFP expression in LO2 cells. Conversely, AFP silencing deteriorated the ER stress-mediated LO2 cell injury and CCl4 administration-induced liver damages by increasing levels of cleaved caspase-3, the C/enhancer binding protein homologous protein expression, mixed lineage kinase domain-like pseudokinase and PERK phosphorylation, but decreasing ATF6 expression. CONCLUSION: ER stress upregulated intra-hepatocyte AFP expression by activating ATF6 during the process of liver injury and intracellular AFP attenuated hepatocyte apoptosis and necroptosis by alleviating ER stress.


Assuntos
Estresse do Retículo Endoplasmático , Hepatopatias , Animais , Apoptose , Hepatócitos/patologia , Humanos , Hepatopatias/patologia , Camundongos , Necroptose , alfa-Fetoproteínas/metabolismo
4.
Oxid Med Cell Longev ; 2022: 7086807, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052160

RESUMO

Mitochondria-associated membranes (MAMs), physical connection sites between the endoplasmic reticulum (ER) and the outer mitochondrial membrane (OMM), are involved in numerous cellular processes, such as calcium ion transport, lipid metabolism, autophagy, ER stress, mitochondria morphology, and apoptosis. Autophagy is a highly conserved intracellular process in which cellular contents are delivered by double-membrane vesicles, called autophagosomes, to the lysosomes for destruction and recycling. Autophagy, typically triggered by stress, eliminates damaged or redundant protein molecules and organelles to maintain regular cellular activity. Dysfunction of MAMs or autophagy is intimately associated with various diseases, including aging, cardiovascular, infections, cancer, multiple toxic agents, and some genetic disorders. Increasing evidence has shown that MAMs play a significant role in autophagy development and maturation. In our study, we concentrated on two opposing functions of MAMs in autophagy: facilitating the formation of autophagosomes and inhibiting autophagy. We recognized the link between MAMs and autophagy in the occurrence and progression of the diseases and therefore collated and summarized the existing intrinsic molecular mechanisms. Furthermore, we draw attention to several crucial data and open issues in the area that may be helpful for further study.


Assuntos
Retículo Endoplasmático , Membranas Mitocondriais , Autofagia , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo
5.
Comput Math Methods Med ; 2022: 4212180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060663

RESUMO

Background: Neuronal apoptosis, which is the primary pathological transform of cerebral injury following ischemic stroke (IS), is considered to be induced by endoplasmic reticulum stress (ERS) by numerous reports. However, ERS biomarkers in IS have not been fully identified yet. Consequently, the present study is aimed at exploring potential blood biomarkers by investigating the molecular mechanisms of ERS promoting neuronal apoptosis following IS development. Methods: A comprehensive analysis was performed with two free-accessible whole-blood datasets (GSE16561 and GSE37587) from the Gene Expression Omnibus database. Genetic information from 107 IS and 24 healthy controls was employed to analyze the differentially expressed genes (DEGs). Genes related to ERS (ERS-DEGs) were identified from the analysis. Enrichment analyses were performed to explore the biofunction and correlated signal pathways of ERS-DEGs. Protein-protein interaction (PPI) network and immune correlation analyses were performed to identify the hub genes along with their correspondent expressions and functions, all of which contributed to incremental diagnostic values. Results: A total of 60 IS-related DEGs were identified, of which 27 genes were confirmed as ERS-DEGs. GO and KEGG enrichment analysis corroborated that upregulated ERS-DEGs were principally enriched in pathways related to immunity, including neutrophil activation and Th17 cell differentiation. Moreover, the GSEA and GSVA indicated that T cell-related signal pathways were the most considerably immune pathways for ERS-DEG enrichment. A total of 10 hub genes were filtered out via the PPI network analysis. Immune correlation analysis confirmed that the expression of hub genes is associated with immune cell infiltration. Conclusions: By integrating and analyzing the two gene expression data profiles, it can be inferred that ERS may be involved in the development of neuronal apoptosis following IS via immune homeostasis. The identified hub genes, which are associated with immune cell infiltration, may serve as potential biomarkers for relative diagnosis and therapy.


Assuntos
Redes Reguladoras de Genes , AVC Isquêmico , Biomarcadores , Biologia Computacional , Estresse do Retículo Endoplasmático/genética , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , AVC Isquêmico/genética
6.
Sci Rep ; 12(1): 14902, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050346

RESUMO

Emerging evidence suggests that 7-ketocholesterol (7-KC), one of the most abundant dietary oxysterols, causes inflammation and cardiovascular diseases. Here we show the deteriorating effects of dietary 7-KC on myocardial ischemia-reperfusion (IR) injury and detailed the molecular mechanisms. A high-fat high-cholesterol diet containing 7-KC (7KWD) for 3 weeks increased the plasma 7-KC level compared with high-fat high-cholesterol diet in mice. In wild-type mice but not in CCR2-/- mice, dietary 7-KC increased the myocardial infarct size after IR. Flow cytometry revealed that the ratio of Ly-6Chigh inflammatory monocytes to total monocytes was increased in the 7KWD group. Unbiased RNA sequencing using murine primary macrophages revealed that 7-KC regulated the expression of transcripts related to inflammation and cholesterol biosynthesis. We further validated that in vitro, 7-KC induced endoplasmic reticulum stress, mitochondrial reactive oxygen species production, and nuclear factor-kappa B activation, which are associated with increased mRNA levels of proinflammatory cytokines. Administration of N-acetyl-L-cysteine or siRNA-mediated knockdown of PKR-like endoplasmic reticulum kinase or endoplasmic reticulum oxidase 1α suppressed the levels of 7-KC-induced inflammation. Dietary 7-KC exacerbates myocardial IR injury through monocyte/macrophage-mediated inflammation. Endoplasmic reticulum stress and oxidative stress are involved in the 7-KC-induced proinflammatory response in macrophages.


Assuntos
Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Animais , Dieta , Estresse do Retículo Endoplasmático , Inflamação/metabolismo , Cetocolesteróis , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão/metabolismo
7.
Biochem Biophys Res Commun ; 628: 155-162, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36099691

RESUMO

BACKGROUND AND AIMS: Increased endoplasmic reticulum (ER) stress is strongly associated with the phenotypic switching of vascular smooth muscle cells (VSMCs) in atherosclerosis. Depletion of the ER Ca2+ content is one of the leading causes of increased ER stress in VSMCs. The ryanodine receptor (RyR) is a major Ca2+ release channel in the sarcoplasmic reticulum membrane. Calmodulin (CaM), which binds to RyR (CaM-RyR), stabilizes the closed state of RyR in the resting state in normal cells. Defective CaM-RyR interactions can cause abnormal Ca2+ leakage through RyR, resulting in decreased Ca2+ content, indicating that defective CaM-RyR interactions may be a cause of increased ER stress. Herein, we used a mouse VSMCs to assess whether CaM-RyR plays a pivotal role in VSMCs phenotypic switching, which is caused by ER stress, and whether dantrolene, which enhances the binding affinity of CaM to RyR, affects VSMCs phenotypic switching. METHODS AND RESULTS: Tunicamycin was used to mimic ER stress in vitro. Tunicamycin-induced ER stress caused CaM to dissociate from the RyR and translocate to the nucleus, which stimulated phenotypic switching through the activation of MEF2 and KLF5. Dantrolene suppressed tunicamycin-induced apoptosis, ER stress (restoring ER Ca2+ content), and phenotypic switching of VSMCs. Suramin, which directly unbinds CaM from RyR, promoted nuclear CaM accumulation with parallel VSMCs phenotypic switching, and dantrolene prevented these effects. CONCLUSIONS: We observed that ER stress causes CaM translocation to the nucleus and drives the phenotypic switching of VSMCs. Thus, restoration of the binding affinity of CaM to RyR may be a therapeutic target for atherosclerosis.


Assuntos
Aterosclerose , Calmodulina , Animais , Aterosclerose/metabolismo , Calmodulina/metabolismo , Dantroleno , Estresse do Retículo Endoplasmático , Camundongos , Músculo Liso Vascular/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Suramina , Tunicamicina/farmacologia
8.
Oxid Med Cell Longev ; 2022: 2297268, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120597

RESUMO

Objective: Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2DM) commonly coexist and act synergistically to drive adverse clinical outcomes. This study is aimed at investigating the effects of exercise intervention and oral hypoglycaemic drug of metformin (MET) alone or combined on hepatic lipid accumulation. To investigate if oxidative stress and endoplasmic reticulum stress (ERS) are involved in lipotoxicity-induced hepatocyte apoptosis in diabetic mice and whether exercise and/or MET alleviated oxidative stress or ERS-apoptosis by AMPK-Nrf2-HO-1 signaling pathway. Methods: Forty db/db mice with diabetes (random blood glucose ≥ 250 mg/dL) were randomly allocated into four groups: control (CON), exercise training alone (EX), metformin treatment alone (MET), and exercise combined with metformin (EM) groups. Hematoxylin-eosin and oil red O staining were carried out to observe hepatic lipid accumulation. Immunohistochemical and TUNEL methods were used to detect the protein expression of the binding immunoglobulin protein (BiP) and superoxide dismutase-1 (SOD1) and the apoptosis level of hepatocytes. ERS-related gene expression and the AMPK-Nrf2-HO-1 signaling pathway were tested by western blotting. Results: Our data showed that db/db mice exhibited increased liver lipid accumulation, which induced oxidative and ER stress of the PERK-eIF2α-ATF4 pathway, and hepatocyte apoptosis. MET combined with exercise training significantly alleviated hepatic lipid accumulation by suppressing BiP expression, the central regulator of ER homeostasis, and its downstream PERK-eIF2α-ATF4 pathway, as well as upregulated the AMPK-Nrf2-HO-1 signaling pathway. Moreover, the combination of exercise and MET displayed protective effects on hepatocyte apoptosis by downregulating Bax expression and TUNEL-positive staining, restoring the balance of cleaved-caspase-3 and caspase-3, and improving the antioxidant defense system to prevent oxidative damage in db/db mice. Conclusion: Compared to MET or exercise intervention alone, the combined exercise and metformin exhibited significant effect on ameliorating hepatic steatosis, inhibiting oxidative and ER stress-induced hepatocyte apoptosis via improving the capacity of the antioxidant defense system and suppression of the PERK-eIF2α-ATF4 pathway. Furthermore, upregulation of AMPK-Nrf2-HO-1 signaling pathway might be a key crosstalk between MET and exercise, which may have additive effects on alleviating hepatic lipid accumulation.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Metformina , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Antioxidantes/farmacologia , Apoptose , Glicemia , Caspase 3/metabolismo , Diabetes Mellitus Experimental/metabolismo , Estresse do Retículo Endoplasmático , Amarelo de Eosina-(YS)/farmacologia , Hematoxilina/farmacologia , Hepatócitos/metabolismo , Hipoglicemiantes/farmacologia , Lipídeos , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais , Superóxido Dismutase-1/metabolismo , Proteína X Associada a bcl-2/metabolismo
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(8): 1256-1262, 2022 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-36073227

RESUMO

OBJECTIVE: The purpose of this study was to determine whether xenon post-conditioning affects mTOR signaling as well as endoplasmic reticulum stress (ERS)-apoptosis pathway in rats with spinal cord ischemia/reperfusion injury. METHODS: Fifty male rats were randomized equally into sham-operated group (Sham group), I/R model group (I/R group), I/R model+ xenon post-conditioning group (Xe group), I/R model+rapamycin (a mTOR signaling pathway inhibitor) treatment group (I/R+ Rapa group), and I/R model + xenon post- conditioning with rapamycin treatment group (Xe + Rapa group).. In the latter 4 groups, SCIRI was induced by clamping the abdominal aorta for 85 min followed by reperfusion for 4 h. Rapamycin (or vehicle) was administered by daily intraperitoneal injection (4 mg/kg) for 3 days before SCIRI, and xenon post-conditioning by inhalation of 1∶1 mixture of xenon and oxygen for 1 h at 1 h after initiation of reperfusion; the rats without xenon post-conditioning were given inhalation of nitrogen and oxygen (1∶ 1). After the reperfusion, motor function and histopathologic changes in the rats were examined. Western blotting and real-time PCR were used to detect the protein and mRNA expressions of GRP78, ATF6, IRE1α, PERK, mTOR, p-mTOR, Bax, Bcl-2 and caspase-3 in the spinal cord. RESULTS: The rats showed significantly lowered hind limb motor function following SCIRI (P < 0.01) with a decreased count of normal neurons, increased mRNA and protein expressions of GRP78, ATF6, IRE1α, PERK, and caspase-3, and elevated p-mTOR/mTOR ratio and Bax/Bcl-2 ratio (P < 0.01). Xenon post-conditioning significantly decreased the mRNA and protein levels of GRP78, ATF6, IRE1α, PERK and caspase-3 (P < 0.05 or 0.01) and reduced p-mTOR/mTOR and Bax/Bcl-2 ratios (P < 0.01) in rats with SCIRI; the mRNA contents and protein levels of GRP78 and ATF6 were significantly decreased in I/R+Rapa group (P < 0.01). Compared with those in Xe group, the rats in I/R+Rapa group and Xe+Rapa had significantly lowered BBB and Tarlov scores of the hind legs (P < 0.01), and caspase-3 protein level and Bax/Bcl-2 ratio were significantly lowered in Xe+Rapa group (P < 0.05 or 0.01). CONCLUSION: By inhibiting ERS and neuronal apoptosis, xenon post- conditioning may have protective effects against SCIRI in rats. The mTOR signaling pathway is partially involved in this process.


Assuntos
Traumatismo por Reperfusão/complicações , Isquemia do Cordão Espinal/complicações , Serina-Treonina Quinases TOR/metabolismo , Xenônio/metabolismo , Animais , Apoptose , Caspase 3/metabolismo , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Endorribonucleases/farmacologia , Injeções Intraperitoneais , Masculino , Neurônios/metabolismo , Neurônios/patologia , Nitrogênio/administração & dosagem , Nitrogênio/metabolismo , Oxigênio/administração & dosagem , Oxigênio/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Isquemia do Cordão Espinal/metabolismo , Isquemia do Cordão Espinal/patologia , Xenônio/administração & dosagem , Xenônio/farmacologia , Xenônio/uso terapêutico , Proteína X Associada a bcl-2/metabolismo
10.
Methods Mol Biol ; 2543: 155-166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36087266

RESUMO

Autophagy and ER stress are most often studied employing a Western blotting approach to the measurement of autophagy by LC3B upregulation and the ER stress sensor signaling proteins PERK (protein kinase R-like endoplasmic reticulum kinase), IRE1, and ATF6 which initiate protein refolding and elongation of the ER until ER homeostasis is returned. If the misfolding of proteins is increased, then ER stress is maintained, and microautophagy of the ER or specifically reticulophagy occurs. However, LC3B, PERK, protein misfolding, and changes in ER mass (reticulophagy) can also be measured in a cell cycle-dependent manner by flow cytometry and the use of antibodies, protein misfolding, and ER tracking fluorescent probes.


Assuntos
Estresse do Retículo Endoplasmático , eIF-2 Quinase , Autofagia , Ciclo Celular , Retículo Endoplasmático/metabolismo , eIF-2 Quinase/metabolismo
11.
PLoS One ; 17(9): e0274057, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36048803

RESUMO

OBJECTIVE: The present study explored whether pyroptosis is involved in the injury process of PC12 cells induced by glucocorticoid (GC) and the regulatory relationship between endoplasmic reticulum stress (ERS) and pyrolysis. METHODS: LDH leakage of PC12 cells was detected by LDH assay. The number of dead cells was detected by SYTOX green nucleic acid staining. The levels of IL-1ß and IL-18 in the supernatants was detected by ELSIA assay. The expression levels of glucose regulated protein 78 (GRP78), cleaved gasdermin D-NT (cleaved-GSDMD-NT), NLR-pyrin domain-containing 3 (NLRP3) and cleaved-caspase-1 were observed by immunofluorescence staining and western blot. RESULTS: The LDH assay revealed that GC exposure significantly increased the release of LDH. The results of SYTOX green acid staining showed that GC exposure significantly increased the number of SYTOX green acid-positive cells. The ELSIA assay revealed that GC exposure significantly increased the levels of IL-1ß and IL-18 in the supernatants. The results of immunofluorescence staining and western blot showed that GC exposure significantly increased the expression of GRP78, cleaved-GSDMD-NT, NLRP3 and cleaved caspase-1. Treatment with the ERS inhibitor tauroursodeoxycholate (TUDCA) and siRNA GSDMD attenuated related damage and downregulated the expression of the abovementioned proteins. CONCLUSION: The present study clearly demonstrated that GC exposure can induce GSDMD-dependent pyrolysis, and ERS is involved in the above damage process.


Assuntos
Interleucina-18 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Caspase 1/metabolismo , Estresse do Retículo Endoplasmático , Glucocorticoides , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células PC12 , Pirólise , Piroptose , Ratos
12.
Toxicology ; 479: 153309, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36058351

RESUMO

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium species that greatly threatens human health. We previously showed that OTA induced cycle arrest, apoptosis and autophagy in human gastric epithelium cells (GES-1). However, the mechanism underlying these effects is still unclear. Here, we showed that OTA exposure increased the expression of endoplasmic reticulum (ER) stress indicators (GRP78, PERK, ATF6, eIF2α, and CHOP), suggesting the activation of the unfolded protein response pathway. 4-phenylbutyric acid (4-PBA), an ER stress-specific inhibitor, attenuated OTA-induced loss of cell viability and apoptosis in GES-1 cells. It also attenuated the G2 phase arrest and autophagy induced by OTA, as evidenced by upregulated G2 phase-related proteins (Cdc2, Cdc25C, and cyclinB1) and downregulated autophagy markers (LC3B and Beclin-1). Moreover, OTA was found to increase ROS generation, and the inhibition of ROS formation by N-acetylcysteine (NAC), an ROS inhibitor, attenuated OTA-induced ER stress and subsequent apoptosis, cell cycle arrest, and autophagy. Collectively, these results suggest that the ROS-mediated ER stress pathway contributes to the OTA toxin-induced cytotoxicity in GES-1 cells. This study offers new insights into the molecular mechanisms underlying OTA toxicity in gastric cells.


Assuntos
Estresse do Retículo Endoplasmático , Ocratoxinas , Acetilcisteína/farmacologia , Apoptose , Proteína Beclina-1 , Epitélio , Humanos , Ocratoxinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo
13.
J Inorg Biochem ; 236: 111972, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36087434

RESUMO

Excessive organophosphate flame retardant (OPFR) use in consumer products has been reported to increase human disease susceptibility. However, the adverse effects of tris(2-chloroethyl) phosphate (TCEP) (a chlorinated alkyl OPFR) on the heart remain unknown. In this study, we tested whether cardiac fibrosis occurred in animal models of TCEP (10 mg/kg b.w./day) administered continuously by gavage for 30 days and evaluated the specific role of sarco/endoplasmic reticulum Ca2+ ATPase (SERCA). First, we confirmed that TCEP could trigger cardiac fibrosis by histopathological observation and cardiac fibrosis markers. We further verified that cardiac fibrosis occurred in animal models of TCEP exposure accompanied by SERCA2a, SERCA2b and SERCA2c downregulation. Notably, inductively coupled plasma-mass spectrometry (ICP-MS) analysis revealed that the cardiac concentrations of Ca2+ increased by 45.3% after TCEP exposure. Using 4-Isopropoxy-N-(2-methylquinolin-8-yl)benzamide (CDN1163, a small molecule SERCA activator), we observed that Ca2+ overload and subsequent cardiac fibrosis caused by TCEP were both alleviated. Simultaneously, the protein levels of endoplasmic reticulum (ER) markers (protein kinase R-like endoplasmic reticulum kinase (PERK), inositol requiring protein 1α (IRE1α), eukaryotic initiation factor 2 α (eIF2α)) were upregulated by TCEP, which could be abrogated by CDN1163 pretreatment. Furthermore, we observed that CDN1163 supplementation prevented overactive autophagy induced by TCEP in the heart. Mechanistically, TCEP could lead to Ca2+ overload by inhibiting the expression of SERCA, thereby triggering ER stress and overactive autophagy, eventually resulting in cardiac fibrosis. Together, our results suggest that the Ca2+ overload/ER stress/autophagy axis can act as a driver of cardiotoxicity induced by TCEP.


Assuntos
Endorribonucleases , Retardadores de Chama , Aminoquinolinas , Animais , Autofagia , Benzamidas/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Endorribonucleases/farmacologia , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 2 em Eucariotos/farmacologia , Fibrose , Retardadores de Chama/metabolismo , Retardadores de Chama/farmacologia , Humanos , Inositol/metabolismo , Inositol/farmacologia , Organofosfatos , Fosfatos/metabolismo , Fosfinas , Proteínas Serina-Treonina Quinases , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/farmacologia
14.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4436-4445, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-36046873

RESUMO

This study aims to investigate the effect of atractylenolide Ⅲ(ATL-Ⅲ) on hydrogen peroxide(H_2O_2)-induced endoplasmic reticulum stress and apoptosis of H9 c2 cells via the ROS/GRP78/caspase-12 signaling pathway.The binding activity of ATL-Ⅲ to GRP78 was determined by molecular docking.The result showed that ATL-Ⅲ had a good binding activity to GRP78, and the binding activity of ATL-Ⅲ was stronger than that of its specific inhibitor.The endoplasmic reticulum stress model of H9 c2 was established by H_2O_2(100 µmol·L~(-1)) treatment.Five groups were designed: blank control group, model group, and ATL-Ⅲ(15, 30, and 60 µmol·L~(-1)) groups.Apoptosis was detected by Hoechst/PI double staining and flow cytometry.The levels of superoxide dismutase(SOD), malondialdehyde(MDA), and lactate dehydrogenase(LDH) were measured by colorimetry.The levels of reactive oxygen species(ROS) and calcium(Ca~(2+)) in cytoplasm were determined by the fluorescence probe DCFH-DA and the calcium fluorescence probe Flou-4, respectively.The protein levels of GRP78, caspase-12, and caspase-3 were determined by Western blot, and the mRNA levels of GRP78 and caspase-12 by RT-qPCR.N-acetyl-L-cysteine(NAC) and 4-phenylbutyric acid(4-PBA) were respectively used to inhibit ROS and GRP78, and then the mechanism of ATL-Ⅲ in protecting the cells from endoplasmic reticulum stress induced by H_2O_2 were deduced.ATL-Ⅲ(15, 30, and 60 µmol·L~(-1)) decreased the apoptosis rate and ROS, MDA, and LDH levels(P<0.01), increased the SOD activity(P<0.01), and down-regulated the protein levels of GRP78, caspase-12, and caspase-3 and the mRNA levels of GRP78 and caspase-12(P<0.05).The addition of NAC decreased the apoptosis rate and ROS, MDA, GRP78, caspase-12, and caspase-3 levels(P<0.01), while it elevated the SOD level(P<0.01).The addition of 4-PBA also decreased the apoptosis rate and the levels of GRP78, caspase-12, caspase-3, and Ca~(2+)(P<0.01).The effect of inhibitors were consistent with that of ATL-Ⅲ.In conclusion, ATL-Ⅲ can protect H9 c2 cardiomyocytes by regulating ROS/GRP78/caspase-12 signaling pathway to inhibit H_2O_2-induced endoplasmic reticulum stress and apoptosis.


Assuntos
Cálcio , Chaperona BiP do Retículo Endoplasmático , Apoptose , Cálcio/farmacologia , Caspase 12/genética , Caspase 12/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Estresse do Retículo Endoplasmático , Lactonas , Simulação de Acoplamento Molecular , RNA Mensageiro , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos , Transdução de Sinais , Superóxido Dismutase/metabolismo
15.
Front Immunol ; 13: 968639, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059491

RESUMO

Acinar cell death and inflammatory response are two important events which determine the severity of acute pancreatitis (AP). Endoplasmic reticulum (ER) stress and necroptosis are involved in this process, but the relationships between them remain unknown. Here, we analyzed the interaction between ER stress and necroptosis and the underlying mechanisms during AP. Experimental pancreatitis was induced in Balb/C mice by caerulein (Cae) and lipopolysaccharide (LPS) or L-arginine (L-Arg) in vivo, and pancreatic acinar cells were also used to follow cellular mechanisms during cholecystokinin (CCK) stimulation in vitro. AP severity was assessed by serum amylase, lipase levels and histological examination. Changes in ER stress, trypsinogen activation and necroptosis levels were analyzed by western blotting, enzyme-linked immunosorbent assay (ELISA), adenosine triphosphate (ATP) analysis or lactate dehydrogenase (LDH) assay. The protein kinase C (PKC)α -mitogen-activated protein kinase (MAPK) -cJun pathway and cathepsin B (CTSB) activation were evaluated by western blotting. Activating protein 1 (AP-1) binding activity was detected by electrophoretic mobility shift assay (EMSA). We found that ER stress is initiated before necroptosis in CCK-stimulated acinar cells in vitro. Inhibition of ER stress by 4-phenylbutyrate (4-PBA) can significantly alleviate AP severity both in two AP models in vivo. 4-PBA markedly inhibited ER stress and necroptosis of pancreatic acinar cells both in vitro and in vivo. Mechanistically, we found that 4-PBA significantly reduced CTSB maturation and PKCα-JNK-cJun pathway -mediated AP-1 activation during AP. Besides, CTSB inhibitor CA074Me markedly blocked PKCα-JNK-cJun pathway -mediated AP-1 activation and necroptosis in AP. However, pharmacologic inhibition of trypsin activity with benzamidine hydrochloride had no effect on PKCα-JNK-cJun pathway and necroptosis in CCK-stimulated pancreatic acinar cells. Furthermore, SR11302, the inhibitor of AP-1, significantly lowered tumor necrosis factor (TNF) α levels, and its subsequent receptor interacting protein kinases (RIP)3 and phosphorylated mixed lineagekinase domain-like (pMLKL) levels, ATP depletion and LDH release rate in CCK-stimulated pancreatic acinar cells. To sum up, all the results indicated that during AP, ER stress promoted pancreatic acinar cell necroptosis through CTSB maturation, thus induced AP-1 activation and TNFα secretion via PKCα-JNK-cJun pathway, not related with trypsin activity. These findings provided potential therapeutic target and treatment strategies for AP or other cell death-related diseases.


Assuntos
Células Acinares , Catepsina B , Estresse do Retículo Endoplasmático , Necroptose , Pancreatite , Fator de Transcrição AP-1 , Células Acinares/metabolismo , Células Acinares/patologia , Doença Aguda , Trifosfato de Adenosina/metabolismo , Animais , Catepsina B/genética , Catepsina B/metabolismo , Estresse do Retículo Endoplasmático/genética , Estresse do Retículo Endoplasmático/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Necroptose/genética , Necroptose/fisiologia , Pancreatite/genética , Pancreatite/metabolismo , Pancreatite/patologia , Proteína Quinase C-alfa/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Tripsina/metabolismo
16.
Front Immunol ; 13: 984508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059525

RESUMO

In the 21st century, intestinal homeostatic imbalance has emerged as a growing health challenge worldwide. Accumulating evidence reveals that excessive intake of saturated fatty acid (SFA) induces intestinal homeostatic imbalance. However, the potential molecular mechanism is still unclear. In the present study, we found that palm oil or palmitic acid (PA) treatment disturbed lipid metabolism homeostasis and triggered endoplasmic reticulum (ER) stress and inflammation in the intestine or intestinal cells of large yellow croaker (Larimichthys crocea). Interestingly, PA treatment significantly decreased phosphatidylethanolamine (PE) content in the intestinal cells. PE supplementation decreased triglyceride content in the intestinal cells induced by PA treatment by inhibiting fatty acid uptake and lipogenesis. PE supplementation suppressed ER stress. Meanwhile, PE supplementation alleviated inflammatory response through p38 MAPK-p65 pathway, reducing the damage of intestinal cells caused by PA treatment to some extent. Our work revealed that intestinal homeostatic imbalance caused by PA treatment was partly due to the decrease of PE content. PE consumption might be a nutritional strategy to regulate intestinal homeostasis in fish and even human beings.


Assuntos
Transtornos do Metabolismo dos Lipídeos , Perciformes , Animais , Dieta , Estresse do Retículo Endoplasmático , Ácidos Graxos/metabolismo , Humanos , Inflamação/induzido quimicamente , Intestinos , Metabolismo dos Lipídeos , Ácido Palmítico/efeitos adversos , Perciformes/metabolismo , Fosfatidiletanolaminas/efeitos adversos , Fosfatidiletanolaminas/metabolismo
17.
Chin J Physiol ; 65(4): 187-198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36073567

RESUMO

Endoplasmic reticulum stress (ERS)-induced inflammation participates in the occurrence of pulmonary arterial hypertension (PAH) by promoting pulmonary vascular remodeling, which involved in the activation of PERK/eIF2α/NF-κB signaling pathway. 18ß-Glycyrrhetinic acid (18ß-GA) has been found efficacious for attenuating PAH through its anti-remodeling effects in our previous research and it remains unclear whether 18ß-GA has an effect on the remodeling caused by ERS-induced inflammation. In this study, we made observations in monocrotaline-induced PAH rats and found improvement of hemodynamic and histopathological parameters, decreases in the right ventricular hypertrophy index, and alleviation of pulmonary vascular remodeling after 18ß-GA administration in vivo. Moreover, 18ß-GA could significantly inhibit the proliferation and DNA synthesis of human pulmonary arterial smooth muscle cells (HPASMCs) induced by platelet-derived growth factor BB. At the cellular and molecular levels, we found that 18ß-GA could significantly reduce the accumulation of misfolded protein in rat lung tissue, inhibit ERS activation, reduce the expression of GRP78, p-PERK, p-eIF2α, and p-NF-κB p65, and increase IκB protein expression. 18ß-GA could inhibit the migration of NF-κB into the nucleus, reduce the contents of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and monocyte chemoattractant protein-1 (MCP-1) in the culture supernatant of HPASMCs, and reduce GRP78, p-PERK, p-eIF2α, p-NF-κB p65, TNF-α, IL-6, and MCP-1 protein expression, increase IκB protein expression in HPASMCs. According to what we observed, this study indicated that 18ß-GA could treat PAH, which is related to the inhibition of PERK/eIF2α/NF-κB signaling pathway.


Assuntos
Ácido Glicirretínico , NF-kappa B , Hipertensão Arterial Pulmonar , Animais , Estresse do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/farmacologia , Humanos , Proteínas I-kappa B/metabolismo , Inflamação/tratamento farmacológico , NF-kappa B/metabolismo , Ratos , Transdução de Sinais , Fator de Necrose Tumoral alfa , Remodelação Vascular
18.
Medicine (Baltimore) ; 101(36): e30280, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36086718

RESUMO

Besides protecting normal cells from various internal and external perturbations, endoplasmic reticulum (ER) stress is also directly related to the pathogenesis of cutaneous melanoma (CM). However, due to the lack of specific molecular biomarkers, ER stress has not been considered a novel treatment target for CM. Here, we identified ER stress-related genes involved in the prognosis of CM patients and constructed an effective model for the prognostic prediction of these patients. First, gene expression data of CM and normal skin tissues from the Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases were retrieved to identify differentially expressed ER stress-related genes in CM. Meanwhile, an independent cohort obtained from the Gene Expression Omnibus (GEO) database was used for validation. The ER stress genes (ZBP1, DIABLO, GNLY, FASLG, AURKA, TNFRSF21, and CD40LG) that were associated with CM prognosis were incorporated into our prognostic model. The functional analyses indicated that the prognostic model was correlated with patient survival, gender, and cancer growth. Multivariate and univariate Cox regressions revealed that the constructed model could serve as an independent prognostic factor for CM patients. The pathway enrichment analysis showed that the risk model was enriched in different immunity and cancer progression-associated pathways. Moreover, the signature model was significantly connected with the immune subtypes, infiltration of immune cells, immune microenvironment, as well as tumor stem cells. The gene function analysis revealed that 7 ER stress genes were differentially expressed in CM patients and were significantly associated with prognosis and several antitumor drugs. Overall, our current model presented predictive value for the prognosis of CM patients and can be further used in the development of novel therapeutic strategies for CM.


Assuntos
Melanoma , Neoplasias Cutâneas , Estresse do Retículo Endoplasmático/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/genética , Prognóstico , Neoplasias Cutâneas/genética , Microambiente Tumoral/genética
19.
Int J Mol Sci ; 23(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36077299

RESUMO

Pancreatic cancer has a high mortality rate due to its aggressive nature and high metastatic rate. When coupled to the difficulties in detecting this type of tumor early and the lack of effective treatments, this cancer is currently one of the most important clinical challenges in the field of oncology. Melitherapy is an innovative therapeutic approach that is based on modifying the composition and structure of cell membranes to treat different diseases, including cancers. In this context, 2-hydroxycervonic acid (HCA) is a melitherapeutic agent developed to combat pancreatic cancer cells, provoking the programmed cell death by apoptosis of these cells by inducing ER stress and triggering the production of ROS species. The efficacy of HCA was demonstrated in vivo, alone and in combination with gemcitabine, using a MIA PaCa-2 cell xenograft model of pancreatic cancer in which no apparent toxicity was evident. HCA is metabolized by α-oxidation to C21:5n-3 (heneicosapentaenoic acid), which in turn also showed anti-proliferative effect in these cells. Given the unmet clinical needs associated with pancreatic cancer, the data presented here suggest that the use of HCA merits further study as a potential therapy for this condition.


Assuntos
Estresse do Retículo Endoplasmático , Neoplasias Pancreáticas , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ácidos Docosa-Hexaenoicos/uso terapêutico , Humanos , Hidroxiácidos , Imidazóis , Neoplasias Pancreáticas/patologia , Sulfonamidas , Tiofenos
20.
Artigo em Inglês | MEDLINE | ID: mdl-36078578

RESUMO

BACKGROUND: Recent studies suggested that individuals with metabolic disorders have altered function of adipocytes and adipose stem cell subpopulations, which impairs tissue homeostasis, promoting insulin resistance and diabetes development. The non-psychoactive phytocannabinoid CBD was found to modulate adipose tissue metabolism, however, its exact role in controlling ASCs' fate is still poorly understood. OBJECTIVES: This investigation aimed to elucidate whether pretreatment of ASCs with CBD can protect against ER stress development and maintain the cytophysiological properties of cells. METHODS: Human ASCs were cultured under control and adipogenic conditions. Prior to the experiments, cells in the experimental group were pretreated with CBD following the addition of an ER stress inducer-tunicamycin. After the experiments, the cells were subsequently tested for expression of the apoptotic, ER stress, and anti-inflammatory-related genes using RT-qPCR. Oxidative stress was analysed with flow cytometric assays. RESULTS: Cells pretreated with CBD displayed decreased apoptosis and enhanced proliferation rate. Additionally, the expression of pro-inflammatory cytokines and miRNAs was significantly reduced. The obtained results also demonstrated an obvious reduction in intracellular accumulated ROS and NO, as well as mitigated ER stress through the down-regulation of IRE-1, PERK, CHOP, and ATF6 transcripts upon CBD treatment. CONCLUSION: The presented data provide the evidence that CBD protects ASCs against ER stress development and its complications and, thus, offers new insights for the management of obesity through the regulation of adipose tissue dynamics.


Assuntos
Canabidiol , Células-Tronco Mesenquimais , Adipogenia , Tecido Adiposo , Canabidiol/farmacologia , Estresse do Retículo Endoplasmático , Humanos
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