BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple b...BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple biological processes,including cellular senescence,apoptosis,sugar and lipid metabolism,oxidative stress,and inflammation.AIM To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.METHODS This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)testing.C57BL/6 mice were also intraperitoneally pretreated with SIRT1,p53,or glutathione peroxidase 4(GPX4)inducers and inhibitors and injected with lipopolysaccharide(LPS)/D-galactosamine(D-GalN)to induce ALF.Gasdermin D(GSDMD)^(-/-)mice were used as an experimental group.Histological changes in liver tissue were monitored by hematoxylin and eosin staining.ALT,AST,glutathione,reactive oxygen species,and iron levels were measured using commercial kits.Ferroptosis-and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction.SIRT1,p53,and GSDMD were assessed by immunofluorescence analysis.RESULTS Serum AST and ALT levels were elevated in patients with ALF.SIRT1,solute carrier family 7a member 11(SLC7A11),and GPX4 protein expression was decreased and acetylated p5,p53,GSDMD,and acyl-CoA synthetase long-chain family member 4(ACSL4)protein levels were elevated in human ALF liver tissue.In the p53 and ferroptosis inhibitor-treated and GSDMD^(-/-)groups,serum interleukin(IL)-1β,tumour necrosis factor alpha,IL-6,IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated.In mice with GSDMD knockout,p53 was reduced,GPX4 was increased,and ferroptotic events(depletion of SLC7A11,elevation of ACSL4,and iron accumulation)were detected.In vitro,knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels,the cytostatic rate,and GSDMD expression,restoring SLC7A11 depletion.Moreover,SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group,accompanied by reduced p53,GSDMD,and ACSL4,and increased SLC7A11 and GPX4.Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalNinduced in vitro and in vivo models.CONCLUSION SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.展开更多
Objective: To demonstrate whether the expression of silent mating type information regulation 2 homolog 1 (SIRT1) affects the level of TGF-β1 and Smad3 in HEK293 cells through regulating mTOR. Methods: First, recombi...Objective: To demonstrate whether the expression of silent mating type information regulation 2 homolog 1 (SIRT1) affects the level of TGF-β1 and Smad3 in HEK293 cells through regulating mTOR. Methods: First, recombinant plasmids DNA (rSIRT1) and siRNA targeting SIRT1 were constructed which were transfected into Human Embryonic Kidney 293 cell (HEK293) cells, respectively. Then, the generation of intracellular ROS in cells was examined by flow cytometry using the oxidation-sensitive probe. Last, the expressions of TGF-β1, smad3, P53, mTOR, p-mTOR, LC3-I and LC3-II in cells were detected to observe the effect of SIRT1 on TGF-β1 Pathway by western blot analysis. Results: We demonstrated that overexpressing of SIRT1 may decrease TGF-β1 and Smad3 expression in HEK293 cells through regulating mTOR. In addition, the result is the opposite when SIRT1 was silent in HEK293 cells. Conclusions: SIRT1 is closely related to TGF-β1/Smad3 pathway that correlates with the regulation of mTOR and ROS generation and causes diabetic nephropathy. The available evidence implies that SIRT1 has great potential as a clinical target for the prevention and treatment of renal fibrosis in the development of DN.展开更多
AIM： To detect the expression of miR-211 in age-related cataract tissue, explore the effects of miR-211 on lens epithelial cell proliferation and apoptosis, and identify its target gene.METHODS： This study used real...AIM： To detect the expression of miR-211 in age-related cataract tissue, explore the effects of miR-211 on lens epithelial cell proliferation and apoptosis, and identify its target gene.METHODS： This study used real-time quantitative polymerase chain reaction（RT-q PCR） to measure the expression of miR-211 and its predicted target gene [silent matingtype information regulation 2 homolog 1（SIRT1）] in 46 anterior lens capsules collected from age-related cataract patients. Human lens epithelial cell line（SRA01/04） cells were transfected with either miR-211 mimics, mimic controls, miR-211 inhibitors or inhibitor controls, 72 h after transfection, miR NA and protein expression of SIRT1 were measured using RT-qP CR and Western blotting; then cells were exposed to 200 μmol/L H2O2 for 1h, whereupon cell viability was measured by MTS assay, caspase-3 assay was performed. Dual luciferase reporter assay was performed to verify the relationship between miR-211 of SIRT1.RESULTS： Compared to the control group, expression of miR-211 was significantly increased（P〈0.001）, the miR NA and protein expression of SIRT1 were significantly decreased（P〈0.001） in the anterior lens capsules of patients with age-related cataracts. Relative to the control group, SIRT1 miR NA and protein levels in the miR-211 mimic group were significantly reduced, cell proliferation activity significantly decreased, and caspase-3 activity was significantly increased（P〈0.001）. In the miR-211 inhibitor group, SIRT1 miRNA and protein expression were significantly increased, cell proliferation activity significantly increased, and caspase-3 activity was significantly decreased（P〈0.001）. A dual luciferase reporter assay confirmed that SIRT1 is a direct target of miR-211.CONCLUSION： miR-211 is highly expressed in the anterior lens capsules of patients with age-related cataracts. By negatively regulating the expression of SIRT1, miR-211 promotes lens epithelial cell apoptosis and inhibits lens epithelial cell proliferation.展开更多
In this editorial,we comment on the article by Zhou et al.The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1(SIRT1)activation in acute liver fa...In this editorial,we comment on the article by Zhou et al.The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1(SIRT1)activation in acute liver failure(ALF).ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage,often posing a high risk of mortality.The predominant form of hepatic cell death in ALF involves apoptosis,ferroptosis,autophagy,pyroptosis,and necroptosis.Glutathione peroxidase 4(GPX4)inhibition sensitizes the cell to ferroptosis and triggers cell death,while Gasdermin D(GSDMD)is a mediator of pyroptosis.The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway,bridging the gap between the two processes.The inhibition of p53 elevates the levels of GPX4,reducing the levels of inflammatory and liver injury markers,ferroptotic events,and GSDMDN protein levels.Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction.SIRT1 is a NAD-dependent deacetylase,and its activation attenuates liver injury and inflammation,accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF.SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation,attenuating LPS/D-GalN-induced ALF.展开更多
AIM:To examine the regulatory role of microRNA-204(miR-204)on silent information regulator 1(SIRT1)and vascular endothelial growth factor(VEGF)under highglucose-induced metabolic memory in human retinal pigment epithe...AIM:To examine the regulatory role of microRNA-204(miR-204)on silent information regulator 1(SIRT1)and vascular endothelial growth factor(VEGF)under highglucose-induced metabolic memory in human retinal pigment epithelial(hRPE)cells.METHODS:Cells were cultured with either normal(5 mmol/L)or high D-glucose(25 mmol/L)concentrations for 8d to establish control and high-glucose groups,respectively.To induce metabolic memory,cells were cultured with 25 mmol/L D-glucose for 4d followed by culture with 5 mmol/L D-glucose for 4d.In addition,exposed in 25 mmol/L D-glucose for 4d and then transfected with 100 nmol/L miR-204 control,miR-204 inhibitor or miR-204 mimic in 5 mmol/L D-glucose for 4d.Quantitative reverse transcription-polymerase chain reaction(RT-qPCR)was used to detect miR-204 mRNA levels.SIRT1 and VEGF protein levels were assessed by immunohistochemical and Western blot.Flow cytometry was used to investigate apoptosis rate.RESULTS:It was found that high glucose promoted miR-204 and VEGF expression,and inhibited SIRT1 activity,even after the return to normal glucose culture conditions.Upregulation of miR-204 promoted apoptosis inhibiting SIRT1 and increasing VEGF expression.However,downregulation of miR-204 produced the opposite effects.CONCLUSION:The study identifies that miR-204 is the upstream target of SIRT1and VEGF,and that miR-204 can protect hRPE cells from the damage caused by metabolic memory through increasing SIRT1 and inhibiting VEGF expression.展开更多
目的探讨利拉鲁肽通过沉默信息调节因子1(silent information regulator 1,SIRT1)/腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)通路改善小鼠肝脏脂质变性的机制。方法将24只健康雄性6周龄C57BL/6J小鼠...目的探讨利拉鲁肽通过沉默信息调节因子1(silent information regulator 1,SIRT1)/腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)通路改善小鼠肝脏脂质变性的机制。方法将24只健康雄性6周龄C57BL/6J小鼠随机分为对照组、模型组、模型+利拉鲁肽组、模型+SIRT1组、模型+SIRT1+利拉鲁肽组、模型+SIRT1-NC组,每组4只。对照组普通饲料饲养,予以等容积生理盐水皮下注射,模型组高脂饲养12周建立代谢相关脂肪性肝病(metabolic dysfunction-associated fatty liver disease,MAFLD)模型,之后3周尾静脉注射SIRT1干扰慢病毒及利拉鲁肽。检测各组小鼠血清甘油三酯和丙氨酸氨基转移酶(alanine aminotransferase,ALT)水平,采用HE染色和油红O染色观察肝组织病理,采用实时荧光定量RT-PCR检测AMPK、SIRT1、肝激酶B1(liver kinase B1,LKB1)和去乙酰化固醇调节元件结合蛋白(sterol regulatory element binding protein-1c,SREBP-1c)基因表达水平,采用Western blot检测蛋白表达水平。结果利拉鲁肽可降低高脂喂养的C57BL/6J小鼠体质量、肝湿重、血清甘油三酯及ALT水平,油红O染色可见肝细胞脂滴减少。与模型组相比,模型+利拉鲁肽组SIRT1(0.212±0.110比0.076±0.010)、AMPK(0.518±0.051比0.248±0.023)、LKB1(1.023±0.039比0.576±0.029)基因表达量和AMPK(0.212±0.026比0.100±0.006)、LKB1(0.413±0.016比0.221±0.015)蛋白表达水平均上调,而SREBP-1c基因(0.727±0.249比9.007±1.530)和蛋白(0.187±0.008比0.824±0.114)表达水平均下调(P均<0.05)。与模型组相比,模型+SIRT1组SIRT1(0.029±0.003比0.076±0.010)、AMPK(0.105±0.013比0.248±0.023)、LKB1(0.333±0.106比0.576±0.029)基因表达量均下调(P均<0.05)。与模型+SIRT1组相比,模型+SIRT1+利拉鲁肽组LKB1(0.945±0.110比0.333±0.106;0.380±0.004比0.145±0.014)、AMPK(0.319±0.051比0.105±0.013;0.181±0.039比0.051±0.012)基因表达量和蛋白表达量均上调,而SREBP-1c基因表达量(4.239±0.554比12.740±0.976)下调(P均<0.05)。结论利拉鲁肽改善C57BL/6J小鼠肝脏脂毒性可能通过直接上调SIRT1/AMPK通路信号分子基因和蛋白表达水平,或间接激活LKB1并增强AMPK基因和蛋白表达、拮抗SREBP-1c基因和蛋白表达,从而降低脂质合成相关分子水平,而干扰SIRT1表达削弱了利拉鲁肽上调SIRT1/AMPK通路改善肝脏脂肪变性的作用。展开更多
基金Supported by National Natural Science Foundation of China,No.82060123Doctoral Start-up Fund of Affiliated Hospital of Guizhou Medical University,No.gysybsky-2021-28+1 种基金Fund Project of Guizhou Provincial Science and Technology Department,No.[2020]1Y299Guizhou Provincial Health Commission,No.gzwjk2019-1-082。
文摘BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple biological processes,including cellular senescence,apoptosis,sugar and lipid metabolism,oxidative stress,and inflammation.AIM To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.METHODS This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)testing.C57BL/6 mice were also intraperitoneally pretreated with SIRT1,p53,or glutathione peroxidase 4(GPX4)inducers and inhibitors and injected with lipopolysaccharide(LPS)/D-galactosamine(D-GalN)to induce ALF.Gasdermin D(GSDMD)^(-/-)mice were used as an experimental group.Histological changes in liver tissue were monitored by hematoxylin and eosin staining.ALT,AST,glutathione,reactive oxygen species,and iron levels were measured using commercial kits.Ferroptosis-and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction.SIRT1,p53,and GSDMD were assessed by immunofluorescence analysis.RESULTS Serum AST and ALT levels were elevated in patients with ALF.SIRT1,solute carrier family 7a member 11(SLC7A11),and GPX4 protein expression was decreased and acetylated p5,p53,GSDMD,and acyl-CoA synthetase long-chain family member 4(ACSL4)protein levels were elevated in human ALF liver tissue.In the p53 and ferroptosis inhibitor-treated and GSDMD^(-/-)groups,serum interleukin(IL)-1β,tumour necrosis factor alpha,IL-6,IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated.In mice with GSDMD knockout,p53 was reduced,GPX4 was increased,and ferroptotic events(depletion of SLC7A11,elevation of ACSL4,and iron accumulation)were detected.In vitro,knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels,the cytostatic rate,and GSDMD expression,restoring SLC7A11 depletion.Moreover,SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group,accompanied by reduced p53,GSDMD,and ACSL4,and increased SLC7A11 and GPX4.Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalNinduced in vitro and in vivo models.CONCLUSION SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.
文摘Objective: To demonstrate whether the expression of silent mating type information regulation 2 homolog 1 (SIRT1) affects the level of TGF-β1 and Smad3 in HEK293 cells through regulating mTOR. Methods: First, recombinant plasmids DNA (rSIRT1) and siRNA targeting SIRT1 were constructed which were transfected into Human Embryonic Kidney 293 cell (HEK293) cells, respectively. Then, the generation of intracellular ROS in cells was examined by flow cytometry using the oxidation-sensitive probe. Last, the expressions of TGF-β1, smad3, P53, mTOR, p-mTOR, LC3-I and LC3-II in cells were detected to observe the effect of SIRT1 on TGF-β1 Pathway by western blot analysis. Results: We demonstrated that overexpressing of SIRT1 may decrease TGF-β1 and Smad3 expression in HEK293 cells through regulating mTOR. In addition, the result is the opposite when SIRT1 was silent in HEK293 cells. Conclusions: SIRT1 is closely related to TGF-β1/Smad3 pathway that correlates with the regulation of mTOR and ROS generation and causes diabetic nephropathy. The available evidence implies that SIRT1 has great potential as a clinical target for the prevention and treatment of renal fibrosis in the development of DN.
基金Supported by the National Natural Science Foundation of China(No.81170836No.81570838)+1 种基金the Natural Science Foundation of Liaoning Province,China(No.2015020474)the Liaoning Provincial Hospital Program for Building Treatment Capacity in Key Clinical Departments(No.LNCCC-D15-2015)
文摘AIM： To detect the expression of miR-211 in age-related cataract tissue, explore the effects of miR-211 on lens epithelial cell proliferation and apoptosis, and identify its target gene.METHODS： This study used real-time quantitative polymerase chain reaction（RT-q PCR） to measure the expression of miR-211 and its predicted target gene [silent matingtype information regulation 2 homolog 1（SIRT1）] in 46 anterior lens capsules collected from age-related cataract patients. Human lens epithelial cell line（SRA01/04） cells were transfected with either miR-211 mimics, mimic controls, miR-211 inhibitors or inhibitor controls, 72 h after transfection, miR NA and protein expression of SIRT1 were measured using RT-qP CR and Western blotting; then cells were exposed to 200 μmol/L H2O2 for 1h, whereupon cell viability was measured by MTS assay, caspase-3 assay was performed. Dual luciferase reporter assay was performed to verify the relationship between miR-211 of SIRT1.RESULTS： Compared to the control group, expression of miR-211 was significantly increased（P〈0.001）, the miR NA and protein expression of SIRT1 were significantly decreased（P〈0.001） in the anterior lens capsules of patients with age-related cataracts. Relative to the control group, SIRT1 miR NA and protein levels in the miR-211 mimic group were significantly reduced, cell proliferation activity significantly decreased, and caspase-3 activity was significantly increased（P〈0.001）. In the miR-211 inhibitor group, SIRT1 miRNA and protein expression were significantly increased, cell proliferation activity significantly increased, and caspase-3 activity was significantly decreased（P〈0.001）. A dual luciferase reporter assay confirmed that SIRT1 is a direct target of miR-211.CONCLUSION： miR-211 is highly expressed in the anterior lens capsules of patients with age-related cataracts. By negatively regulating the expression of SIRT1, miR-211 promotes lens epithelial cell apoptosis and inhibits lens epithelial cell proliferation.
文摘In this editorial,we comment on the article by Zhou et al.The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1(SIRT1)activation in acute liver failure(ALF).ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage,often posing a high risk of mortality.The predominant form of hepatic cell death in ALF involves apoptosis,ferroptosis,autophagy,pyroptosis,and necroptosis.Glutathione peroxidase 4(GPX4)inhibition sensitizes the cell to ferroptosis and triggers cell death,while Gasdermin D(GSDMD)is a mediator of pyroptosis.The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway,bridging the gap between the two processes.The inhibition of p53 elevates the levels of GPX4,reducing the levels of inflammatory and liver injury markers,ferroptotic events,and GSDMDN protein levels.Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction.SIRT1 is a NAD-dependent deacetylase,and its activation attenuates liver injury and inflammation,accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF.SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation,attenuating LPS/D-GalN-induced ALF.
基金Supported by the Training Project for Young and Middleaged Core Talents in Health System of Fujian Province(No.2016-ZQN-62)Natural Science Foundation of Fujian Province(No.2020J01652).
文摘AIM:To examine the regulatory role of microRNA-204(miR-204)on silent information regulator 1(SIRT1)and vascular endothelial growth factor(VEGF)under highglucose-induced metabolic memory in human retinal pigment epithelial(hRPE)cells.METHODS:Cells were cultured with either normal(5 mmol/L)or high D-glucose(25 mmol/L)concentrations for 8d to establish control and high-glucose groups,respectively.To induce metabolic memory,cells were cultured with 25 mmol/L D-glucose for 4d followed by culture with 5 mmol/L D-glucose for 4d.In addition,exposed in 25 mmol/L D-glucose for 4d and then transfected with 100 nmol/L miR-204 control,miR-204 inhibitor or miR-204 mimic in 5 mmol/L D-glucose for 4d.Quantitative reverse transcription-polymerase chain reaction(RT-qPCR)was used to detect miR-204 mRNA levels.SIRT1 and VEGF protein levels were assessed by immunohistochemical and Western blot.Flow cytometry was used to investigate apoptosis rate.RESULTS:It was found that high glucose promoted miR-204 and VEGF expression,and inhibited SIRT1 activity,even after the return to normal glucose culture conditions.Upregulation of miR-204 promoted apoptosis inhibiting SIRT1 and increasing VEGF expression.However,downregulation of miR-204 produced the opposite effects.CONCLUSION:The study identifies that miR-204 is the upstream target of SIRT1and VEGF,and that miR-204 can protect hRPE cells from the damage caused by metabolic memory through increasing SIRT1 and inhibiting VEGF expression.
