Endoplasmic reticulum(ER)stress occurs when ER homeostasis is perturbed with accumulation of unfolded/misfolded protein or calcium depletion.The unfolded protein response(UPR),comprising of inositol-requiring enzyme 1...Endoplasmic reticulum(ER)stress occurs when ER homeostasis is perturbed with accumulation of unfolded/misfolded protein or calcium depletion.The unfolded protein response(UPR),comprising of inositol-requiring enzyme 1 a(IRE1 a),double-stranded RNA-dependent protein kinase(PKR)-like ER kinase(PERK)and activating transcription factor 6(ATF6)signaling pathways,is a protective cellular response activated by ER stress.However,UPR activation can also induce cell death upon persistent ER stress.The liver is susceptible to ER stress given its synthetic and other biological functions.Numerous studies from human liver samples and animal disease models have indicated a crucial role of ER stress and the UPR signaling pathways in the pathogenesis of liver diseases,including non-alcoholic fatty liver disease(NAFLD),alcoholic liver disease(ALD),alpha-1 antitrypsin(AAT)deficiency(AATD),cholestatic liver disease,drug-induced liver injury,ischemia/reperfusion(I/R)injury,viral hepatitis and hepatocel-lular carcinoma(HCC).Extensive investigations have demonstrated the potential underlying mechanisms of the induction of ER stress and the contribution of the UPR pathways during the development of the diseases.Moreover,ER stress and the UPR proteins and genes have become emerging therapeutic targets to treat liver diseases.展开更多
In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS...In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.展开更多
Sublytic complement C5b-9 complexes can cause cell apoptosis, but the mechanism of glomerular mesangial cell (GMC) apoptosis mediated by these complexes has not been well defined. The activating transcription factor...Sublytic complement C5b-9 complexes can cause cell apoptosis, but the mechanism of glomerular mesangial cell (GMC) apoptosis mediated by these complexes has not been well defined. The activating transcription factor 3 (ATF3) gene is an immediate early gene for the cell to cope with a variety of stress signals and can promote apoptosis of some cells. In this study, ATF3 expression and cell apoptosis in GMCs induced by sublytic C5b-9 were measured, and then the effects of ATF3 gene over-expression or knockdown on GMC apoptosis induced by sublytic C5b-9 were examined at a fixed time. The results showed that both ATF3 expression and GMC apoptosis were markedly increased and ATF3 over-expression obviously increased sublytic C5b-9-induced GMC apoptosis, whereas ATF3 gene silencing had a significant opposite effect. Collectively, these findings indicate that upregulation of ATF3 gene expression is involved in regulating GMC apoptosis induced by sublytic C5b-9 complexes.展开更多
【目的】探讨四逆汤对阿霉素诱导的慢性心力衰竭(CHF)大鼠内质网应激的影响。【方法】从90只大鼠中随机选取15只作为正常组,其余大鼠腹腔注射阿霉素构建CHF模型,同时,正常组给予腹腔注射生理盐水。造模结束后,正常组大鼠全部存活,造模...【目的】探讨四逆汤对阿霉素诱导的慢性心力衰竭(CHF)大鼠内质网应激的影响。【方法】从90只大鼠中随机选取15只作为正常组,其余大鼠腹腔注射阿霉素构建CHF模型,同时,正常组给予腹腔注射生理盐水。造模结束后,正常组大鼠全部存活,造模大鼠存活60只。再将60只CHF大鼠随机分为5组,即模型组,四逆汤低、中、高剂量组,曲美他嗪组,每组12只。四逆汤低、中、高剂量组分别给予1.4、4.2、12.6(生药)g·kg^(-1)·d^(-1)灌胃,曲美他嗪组给予曲美他嗪10 mg·kg^(-1)·d^(-1)灌胃,正常组和模型组给予相同体积的生理盐水灌胃。连续给药4周。采用小动物超声测量左心室舒张末期直径(LVEDD)、左心室射血分数(LVEF)和左心室缩短分数(LVFS)变化;采用酶联免疫吸附分析(ELISA)检测血浆脑钠肽(BNP)和血管紧张素Ⅱ(AngⅡ)水平;采用实时荧光定量聚合酶链反应(PCR)技术检测心肌组织葡萄糖调节蛋白78(GRP78)、RNA依赖的蛋白激酶样内质网激酶(PERK)和活化转录因子4(ATF4)mRNA表达。【结果】与正常组比较,模型组大鼠LVEDD显著增大,LVEF、LVFS均显著降低,血浆BNP和AngⅡ含量升高,心肌组织GRP78、PERK及ATF4 m RNA表达量升高(P <0.01);与模型组比较,四逆汤低、中、高剂量组及曲美他嗪组LVEDD降低,LVEF、LVFS均显著增加,血浆BNP和AngⅡ含量减少,心肌组织GRP78、PERK及ATF4 m RNA表达量降低,且呈剂量依赖性,其中,四逆汤高剂量组及曲美他嗪组差异均有统计学意义(P <0.05或P <0.01)。【结论】四逆汤可改善慢性心力衰竭大鼠模型心脏功能,其机制可能与抑制PERK/ATF4信号通路从而减轻内质网应激有关。展开更多
基金This work was supported by USA National Institute of Diabetes and Digestive and Kidney Diseases(NIDDK)R01 DK093807.
文摘Endoplasmic reticulum(ER)stress occurs when ER homeostasis is perturbed with accumulation of unfolded/misfolded protein or calcium depletion.The unfolded protein response(UPR),comprising of inositol-requiring enzyme 1 a(IRE1 a),double-stranded RNA-dependent protein kinase(PKR)-like ER kinase(PERK)and activating transcription factor 6(ATF6)signaling pathways,is a protective cellular response activated by ER stress.However,UPR activation can also induce cell death upon persistent ER stress.The liver is susceptible to ER stress given its synthetic and other biological functions.Numerous studies from human liver samples and animal disease models have indicated a crucial role of ER stress and the UPR signaling pathways in the pathogenesis of liver diseases,including non-alcoholic fatty liver disease(NAFLD),alcoholic liver disease(ALD),alpha-1 antitrypsin(AAT)deficiency(AATD),cholestatic liver disease,drug-induced liver injury,ischemia/reperfusion(I/R)injury,viral hepatitis and hepatocel-lular carcinoma(HCC).Extensive investigations have demonstrated the potential underlying mechanisms of the induction of ER stress and the contribution of the UPR pathways during the development of the diseases.Moreover,ER stress and the UPR proteins and genes have become emerging therapeutic targets to treat liver diseases.
文摘In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.
文摘Sublytic complement C5b-9 complexes can cause cell apoptosis, but the mechanism of glomerular mesangial cell (GMC) apoptosis mediated by these complexes has not been well defined. The activating transcription factor 3 (ATF3) gene is an immediate early gene for the cell to cope with a variety of stress signals and can promote apoptosis of some cells. In this study, ATF3 expression and cell apoptosis in GMCs induced by sublytic C5b-9 were measured, and then the effects of ATF3 gene over-expression or knockdown on GMC apoptosis induced by sublytic C5b-9 were examined at a fixed time. The results showed that both ATF3 expression and GMC apoptosis were markedly increased and ATF3 over-expression obviously increased sublytic C5b-9-induced GMC apoptosis, whereas ATF3 gene silencing had a significant opposite effect. Collectively, these findings indicate that upregulation of ATF3 gene expression is involved in regulating GMC apoptosis induced by sublytic C5b-9 complexes.
文摘【目的】探讨四逆汤对阿霉素诱导的慢性心力衰竭(CHF)大鼠内质网应激的影响。【方法】从90只大鼠中随机选取15只作为正常组,其余大鼠腹腔注射阿霉素构建CHF模型,同时,正常组给予腹腔注射生理盐水。造模结束后,正常组大鼠全部存活,造模大鼠存活60只。再将60只CHF大鼠随机分为5组,即模型组,四逆汤低、中、高剂量组,曲美他嗪组,每组12只。四逆汤低、中、高剂量组分别给予1.4、4.2、12.6(生药)g·kg^(-1)·d^(-1)灌胃,曲美他嗪组给予曲美他嗪10 mg·kg^(-1)·d^(-1)灌胃,正常组和模型组给予相同体积的生理盐水灌胃。连续给药4周。采用小动物超声测量左心室舒张末期直径(LVEDD)、左心室射血分数(LVEF)和左心室缩短分数(LVFS)变化;采用酶联免疫吸附分析(ELISA)检测血浆脑钠肽(BNP)和血管紧张素Ⅱ(AngⅡ)水平;采用实时荧光定量聚合酶链反应(PCR)技术检测心肌组织葡萄糖调节蛋白78(GRP78)、RNA依赖的蛋白激酶样内质网激酶(PERK)和活化转录因子4(ATF4)mRNA表达。【结果】与正常组比较,模型组大鼠LVEDD显著增大,LVEF、LVFS均显著降低,血浆BNP和AngⅡ含量升高,心肌组织GRP78、PERK及ATF4 m RNA表达量升高(P <0.01);与模型组比较,四逆汤低、中、高剂量组及曲美他嗪组LVEDD降低,LVEF、LVFS均显著增加,血浆BNP和AngⅡ含量减少,心肌组织GRP78、PERK及ATF4 m RNA表达量降低,且呈剂量依赖性,其中,四逆汤高剂量组及曲美他嗪组差异均有统计学意义(P <0.05或P <0.01)。【结论】四逆汤可改善慢性心力衰竭大鼠模型心脏功能,其机制可能与抑制PERK/ATF4信号通路从而减轻内质网应激有关。