Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after...Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after cerebral ischemic injury.Sonic hedgehog signaling participates in fibrosis in the heart,liver,lung,and kidney.Whether Shh signaling modulates fibrotic scar formation after cerebral ischemic stroke and the underlying mechanisms are unclear.In this study,we found that Sonic Hedgehog expression was upregulated in patients with acute ischemic stroke and in a middle cerebral artery occlusion/reperfusion injury rat model.Both Sonic hedgehog and Mitofusin 2 showed increased expression in the middle cerebral artery occlusion rat model and in vitro fibrosis cell model induced by transforming growth factor-beta 1.Activation of the Sonic hedgehog signaling pathway enhanced the expression of phosphorylated Smad 3 and Mitofusin 2 proteins,promoted the formation of fibrotic scars,protected synapses or promoted synaptogenesis,alleviated neurological deficits following middle cerebral artery occlusion/reperfusion injury,reduced cell apoptosis,facilitated the transformation of meninges fibroblasts into myofibroblasts,and enhanced the proliferation and migration of meninges fibroblasts.The Smad3 phosphorylation inhibitor SIS3 reversed the effects induced by Sonic hedgehog signaling pathway activation.Bioinformatics analysis revealed significant correlations between Sonic hedgehog and Smad3,between Sonic hedgehog and Mitofusin 2,and between Smad3 and Mitofusin 2.These findings suggest that Sonic hedgehog signaling may influence Mitofusin 2 expression by regulating Smad3 phosphorylation,thereby modulating the formation of early fibrotic scars following cerebral ischemic stroke and affecting prognosis.The Sonic Hedgehog signaling pathway may serve as a new therapeutic target for stroke treatment.展开更多
目的:观察荔枝核总黄酮(total flavone from Litchi chinensis Sonn,TFL)对二甲基亚硝胺(dimethylnitrosamine,DMN)诱导的肝纤维化大鼠肝脏组Smads信号通路中关键信号传导分子Smad3、Smad4及基质金属蛋白酶抑制剂-1(tissue inhibitor of...目的:观察荔枝核总黄酮(total flavone from Litchi chinensis Sonn,TFL)对二甲基亚硝胺(dimethylnitrosamine,DMN)诱导的肝纤维化大鼠肝脏组Smads信号通路中关键信号传导分子Smad3、Smad4及基质金属蛋白酶抑制剂-1(tissue inhibitor of metalloproteinase-1TIMP-1)表达水平的变化,探讨TFL抗肝纤维化的作用机制.方法:90只S D大鼠随机平均分成正常对照组、模型组、秋水仙碱组不同浓度的TFL[200、100、50 mg/(kg·d)].用DMN腹腔注射诱导大鼠肝纤维化模型,造模同时灌胃给药.1次/d,共给6 wk,于实验第6周后处死大鼠,取血清测定谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)的含量.取留取肝脏同一部位行Masson染色观察大鼠病理改变及肝纤维化程度;免疫组织化学法检测Smad3、Smad4、TIMP-1表达量,实时荧光定量PCR检测(real-time quantitative PCR,qRT-PCR)检测Smad3、Smad4、TIMP-1m RNA表达量.结果:与模型组比较,TFL能降低血清ALT、AST含量,Masson染色病理显示TFL能显著减轻大鼠肝纤维化程度;与空白对照组比较,模型组大鼠的肝纤维化程度明显增加,肝组织Smad3、Smad4及TIMP-1的表达明显增强(P<0.05);与模型组比较,TFL各剂量组和秋水仙碱组肝组织Smad3、Smad4、TIMP-1的表达不同程度的降低(P<0.05).结论:T F L可减轻实验性大鼠肝损伤及改善肝纤维化程度,其机制与降低S m a d3、Smad4及TIMP-1的表达有密切关系,可能与改善肝功能、抑制肝细胞变性坏死,从而抑制胶原蛋白的合成和沉积减少细胞外基质有关.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82171456(to QY)and 81971229(to QY)the Natural Science Foundation of Chongqing,Nos.CSTC2021JCYJ-MSXMX0263(to QY)and CSTB2023NSCQ-MSX1015(to XL)Doctoral Innovation Project of The First Affiliated Hospital of Chongqing Medical University,Nos.CYYY-BSYJSCXXM-202318(to JW)and CYYY-BSYJSCXXM-202327(to HT).
文摘Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after cerebral ischemic injury.Sonic hedgehog signaling participates in fibrosis in the heart,liver,lung,and kidney.Whether Shh signaling modulates fibrotic scar formation after cerebral ischemic stroke and the underlying mechanisms are unclear.In this study,we found that Sonic Hedgehog expression was upregulated in patients with acute ischemic stroke and in a middle cerebral artery occlusion/reperfusion injury rat model.Both Sonic hedgehog and Mitofusin 2 showed increased expression in the middle cerebral artery occlusion rat model and in vitro fibrosis cell model induced by transforming growth factor-beta 1.Activation of the Sonic hedgehog signaling pathway enhanced the expression of phosphorylated Smad 3 and Mitofusin 2 proteins,promoted the formation of fibrotic scars,protected synapses or promoted synaptogenesis,alleviated neurological deficits following middle cerebral artery occlusion/reperfusion injury,reduced cell apoptosis,facilitated the transformation of meninges fibroblasts into myofibroblasts,and enhanced the proliferation and migration of meninges fibroblasts.The Smad3 phosphorylation inhibitor SIS3 reversed the effects induced by Sonic hedgehog signaling pathway activation.Bioinformatics analysis revealed significant correlations between Sonic hedgehog and Smad3,between Sonic hedgehog and Mitofusin 2,and between Smad3 and Mitofusin 2.These findings suggest that Sonic hedgehog signaling may influence Mitofusin 2 expression by regulating Smad3 phosphorylation,thereby modulating the formation of early fibrotic scars following cerebral ischemic stroke and affecting prognosis.The Sonic Hedgehog signaling pathway may serve as a new therapeutic target for stroke treatment.
文摘目的:观察荔枝核总黄酮(total flavone from Litchi chinensis Sonn,TFL)对二甲基亚硝胺(dimethylnitrosamine,DMN)诱导的肝纤维化大鼠肝脏组Smads信号通路中关键信号传导分子Smad3、Smad4及基质金属蛋白酶抑制剂-1(tissue inhibitor of metalloproteinase-1TIMP-1)表达水平的变化,探讨TFL抗肝纤维化的作用机制.方法:90只S D大鼠随机平均分成正常对照组、模型组、秋水仙碱组不同浓度的TFL[200、100、50 mg/(kg·d)].用DMN腹腔注射诱导大鼠肝纤维化模型,造模同时灌胃给药.1次/d,共给6 wk,于实验第6周后处死大鼠,取血清测定谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)的含量.取留取肝脏同一部位行Masson染色观察大鼠病理改变及肝纤维化程度;免疫组织化学法检测Smad3、Smad4、TIMP-1表达量,实时荧光定量PCR检测(real-time quantitative PCR,qRT-PCR)检测Smad3、Smad4、TIMP-1m RNA表达量.结果:与模型组比较,TFL能降低血清ALT、AST含量,Masson染色病理显示TFL能显著减轻大鼠肝纤维化程度;与空白对照组比较,模型组大鼠的肝纤维化程度明显增加,肝组织Smad3、Smad4及TIMP-1的表达明显增强(P<0.05);与模型组比较,TFL各剂量组和秋水仙碱组肝组织Smad3、Smad4、TIMP-1的表达不同程度的降低(P<0.05).结论:T F L可减轻实验性大鼠肝损伤及改善肝纤维化程度,其机制与降低S m a d3、Smad4及TIMP-1的表达有密切关系,可能与改善肝功能、抑制肝细胞变性坏死,从而抑制胶原蛋白的合成和沉积减少细胞外基质有关.
