Sodium-glucose cotransporter 2(SGLT2)inhibitors reduce cardiovascular mortality in patients with diabetes mellitus but the protective mechanism remains elusive.Here we demonstrated that the SGLT2 inhibitor,Empaglifloz...Sodium-glucose cotransporter 2(SGLT2)inhibitors reduce cardiovascular mortality in patients with diabetes mellitus but the protective mechanism remains elusive.Here we demonstrated that the SGLT2 inhibitor,Empagliflozin(EMPA),suppresses cardiomyocytes autosis(autophagic cell death)to confer cardioprotective effects.Using myocardial infarction(Ml)mouse models with and without diabetes mellitus,EMPA treatment significantly reduced infarct size,and myocardial fibrosis,thereby leading to improved cardiac function and survival.In the context of ischemia and nutritional glucose deprivation where autosis is already highly stimulated,EMPA directly inhibits the activity of the Na^(+)/H^(+)exchanger 1(NHE1)in the cardiomyocytes to regulate excessive autophagy.Knockdown of NHE1 significantly rescued glucose deprivation-induced autosis.In contrast,overexpression of NHE1 aggravated the cardiomyocytes death in response to starvation,which was effectively rescued by EMPA treatment.Furthermore,in vitro and in vivo analysis of NHE1 and Beclin 1 knockout mice validated that EMPA s cardioprotective effects are at least in part through downregulation of autophagic flux.These findings provide new insights for drug development,specifically targeting NHE1 and autosis for ventricular remodeling and heart failure after Ml in both diabetic and non-diabetic patients.展开更多
As post-mitotic cells with great energy demands, neurons depend upon the homeostatic and waste-recycling functions provided by autophagy. In addition, autophagy also promotes survival during periods of harsh stress an...As post-mitotic cells with great energy demands, neurons depend upon the homeostatic and waste-recycling functions provided by autophagy. In addition, autophagy also promotes survival during periods of harsh stress and targets aggregate-prone proteins associated with neurodegeneration for degradation. Despite this, autophagy has also been controversially described as a mechanism of programmed cell death. Instances of autophagic cell death are typically associated with elevated numbers of cytoplasmic autophagosomes, which have been assumed to lead to excessive degradation of cellular components. Due to the high activity and reliance on autophagy in neurons, these cells may be particularly susceptible to autophagic death. In this review, we summarize and assess current evidence in support of autophagic cell death in neurons, as well as how the dysregulation of autophagy commonly seen in neurodegeneration can contribute to neuron loss. From here, we discuss potential treatment strategies relevant to such cell-death pathways.展开更多
基金Y Xiang received support from the National Key Research and Development Program of China(2017YFC1700402)National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(81822048 and 81770256)Fund of Shanghai Pudong New Area(PDZY-2018-0603).
文摘Sodium-glucose cotransporter 2(SGLT2)inhibitors reduce cardiovascular mortality in patients with diabetes mellitus but the protective mechanism remains elusive.Here we demonstrated that the SGLT2 inhibitor,Empagliflozin(EMPA),suppresses cardiomyocytes autosis(autophagic cell death)to confer cardioprotective effects.Using myocardial infarction(Ml)mouse models with and without diabetes mellitus,EMPA treatment significantly reduced infarct size,and myocardial fibrosis,thereby leading to improved cardiac function and survival.In the context of ischemia and nutritional glucose deprivation where autosis is already highly stimulated,EMPA directly inhibits the activity of the Na^(+)/H^(+)exchanger 1(NHE1)in the cardiomyocytes to regulate excessive autophagy.Knockdown of NHE1 significantly rescued glucose deprivation-induced autosis.In contrast,overexpression of NHE1 aggravated the cardiomyocytes death in response to starvation,which was effectively rescued by EMPA treatment.Furthermore,in vitro and in vivo analysis of NHE1 and Beclin 1 knockout mice validated that EMPA s cardioprotective effects are at least in part through downregulation of autophagic flux.These findings provide new insights for drug development,specifically targeting NHE1 and autosis for ventricular remodeling and heart failure after Ml in both diabetic and non-diabetic patients.
基金funded by a Wellcome Trust Principal Research Fellowshipthe NIHR Biomedical Research Unit in Dementia at Addenbrooke’s Hospitalsupported by Plymouth University and Northcott Medical Foundation
文摘As post-mitotic cells with great energy demands, neurons depend upon the homeostatic and waste-recycling functions provided by autophagy. In addition, autophagy also promotes survival during periods of harsh stress and targets aggregate-prone proteins associated with neurodegeneration for degradation. Despite this, autophagy has also been controversially described as a mechanism of programmed cell death. Instances of autophagic cell death are typically associated with elevated numbers of cytoplasmic autophagosomes, which have been assumed to lead to excessive degradation of cellular components. Due to the high activity and reliance on autophagy in neurons, these cells may be particularly susceptible to autophagic death. In this review, we summarize and assess current evidence in support of autophagic cell death in neurons, as well as how the dysregulation of autophagy commonly seen in neurodegeneration can contribute to neuron loss. From here, we discuss potential treatment strategies relevant to such cell-death pathways.
