目的利用心肌梗死后心力衰竭模型研究组织激肽释放酶(TK)和缓激肽(BK)改善心功能、抑制心肌纤维化的机制。方法冠状动脉结扎后1周,纯化的TK及BK连续皮下渗透给药4周,5周后处死动物。导管法检测各组动物的心功能,天狼红染色检测胶原的沉...目的利用心肌梗死后心力衰竭模型研究组织激肽释放酶(TK)和缓激肽(BK)改善心功能、抑制心肌纤维化的机制。方法冠状动脉结扎后1周,纯化的TK及BK连续皮下渗透给药4周,5周后处死动物。导管法检测各组动物的心功能,天狼红染色检测胶原的沉积,银染法测量心肌细胞的面积,免疫组织化学法检测Ⅰ、Ⅲ型胶原,W estern b lot-ting检测TGF-β1、Sm ad 2和phosph-Sm ad 2的表达,化学发光法检测一氧化氮(NO)和过氧化物的含量。结果TK及BK能明显改善心功能,对梗死面积无影响。治疗组胶原的沉积明显减少,细胞肥大减轻,TGF-β1、Smad的表达和磷酸化减少,NO的合成增加,过氧化物蓄积减轻。结论TK及BK对心肌梗死后的心力衰竭有治疗作用,抑制TGF-β1活化及过氧化物形成是主要的机制。展开更多
The tissue kallikrein-kinin system exerts a wide spectrum of biological activities in the cardiovascular, renal and central nervous systems. Tissue kallikrein-kinin modulates the proliferation, viability, mobility and...The tissue kallikrein-kinin system exerts a wide spectrum of biological activities in the cardiovascular, renal and central nervous systems. Tissue kallikrein-kinin modulates the proliferation, viability, mobility and functional activity of certain stem cell populations, namely mesenchymal stem cells(MSCs), endothelial progenitor cells(EPCs), mononuclear cell subsets and neural stem cells. Stimulation of these stem cells by tissue kallikrein-kinin may lead to protection against renal, cardiovascular and neural damage by inhibiting apoptosis, inflammation, fibrosis and oxidative stress and promoting neovascularization. Moreover, MSCs and EPCs genetically modified with tissue kallikrein are resistant to hypoxia- and oxidative stress-induced apoptosis, and offer enhanced protective actions in animal models of heart and kidney injury and hindlimb ischemia. In addition, activation of the plasma kallikrein-kinin system promotes EPC recruitment to the inflamed synovium of arthritic rats. Conversely, cleaved high molecular weight kininogen, a product of plasma kallikrein, reduces the viability and vasculogenic activity of EPCs. Therefore, kallikrein-kinin provides a new approach in enhancing the efficacy of stem cell therapy for human diseases.展开更多
文摘目的利用心肌梗死后心力衰竭模型研究组织激肽释放酶(TK)和缓激肽(BK)改善心功能、抑制心肌纤维化的机制。方法冠状动脉结扎后1周,纯化的TK及BK连续皮下渗透给药4周,5周后处死动物。导管法检测各组动物的心功能,天狼红染色检测胶原的沉积,银染法测量心肌细胞的面积,免疫组织化学法检测Ⅰ、Ⅲ型胶原,W estern b lot-ting检测TGF-β1、Sm ad 2和phosph-Sm ad 2的表达,化学发光法检测一氧化氮(NO)和过氧化物的含量。结果TK及BK能明显改善心功能,对梗死面积无影响。治疗组胶原的沉积明显减少,细胞肥大减轻,TGF-β1、Smad的表达和磷酸化减少,NO的合成增加,过氧化物蓄积减轻。结论TK及BK对心肌梗死后的心力衰竭有治疗作用,抑制TGF-β1活化及过氧化物形成是主要的机制。
基金Supported by National Institutes of Health,No.HL118516,HL29397 and HL44083
文摘The tissue kallikrein-kinin system exerts a wide spectrum of biological activities in the cardiovascular, renal and central nervous systems. Tissue kallikrein-kinin modulates the proliferation, viability, mobility and functional activity of certain stem cell populations, namely mesenchymal stem cells(MSCs), endothelial progenitor cells(EPCs), mononuclear cell subsets and neural stem cells. Stimulation of these stem cells by tissue kallikrein-kinin may lead to protection against renal, cardiovascular and neural damage by inhibiting apoptosis, inflammation, fibrosis and oxidative stress and promoting neovascularization. Moreover, MSCs and EPCs genetically modified with tissue kallikrein are resistant to hypoxia- and oxidative stress-induced apoptosis, and offer enhanced protective actions in animal models of heart and kidney injury and hindlimb ischemia. In addition, activation of the plasma kallikrein-kinin system promotes EPC recruitment to the inflamed synovium of arthritic rats. Conversely, cleaved high molecular weight kininogen, a product of plasma kallikrein, reduces the viability and vasculogenic activity of EPCs. Therefore, kallikrein-kinin provides a new approach in enhancing the efficacy of stem cell therapy for human diseases.