Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an imp...Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.展开更多
基金supported by the National Natural Science Foundation of China(82270386,82070252,and 8207025)the Zhejiang Provincial Medical and Health Science and Technology Plan(2023RC020)the Zhejiang Provincial Natural Science Foundation(LR21H020001).
文摘Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.
文摘背景与目的谷胱甘肽S转移酶M1(glutathione S-transferase M1,GSTM1)基因是参与体内多种致癌物代谢的重要的II相代谢酶,其基因多态性被认为与人肺癌遗传易感性有关。本研究旨在探讨天津地区汉族人群GSTM1基因多态性与肺癌遗传易感性之间的关系。方法采用SYBR green I实时荧光PCR熔解曲线分析方法检测天津地区265例肺癌患者和307例对照者GSTM1基因多态性,应用病例对照研究分析其与肺癌易感性及不同病理类型之间的关系。结果①GSTM1(-)基因型在肺癌组和对照组的分布频率分别为56.6%和57.0%,两组之间无统计学差别(χ2=0.831,P=0.362)。经性别、年龄、吸烟状况调整后分析,携带GSTM1(-)基因型个体未增加患肺癌危险性(OR=0.840,95%CI:0.578-1.221,P=0.362)。②按病理分层分析GSTM1基因型与肺癌各病理类型之间的关系,其中鳞癌、腺癌、小细胞肺癌与其它病理类型肺癌患者GSTM1(-)基因型分布频率分别为65.8%、48.5%、47.8%和52.2%,与对照组相比,不同病理类型患者肺癌危险性均无明显统计学差异(P>0.05)。结论在天津地区人群中GSTM1基因多态性与肺癌遗传易感性之间无相关性。
