目的研究体外低氧诱导小鼠心脏成纤维细胞（cardiac fibroblasts，CFs）向心脏肌成纤维细胞（cardiac myofibroblasts，CMFs）表型转换过程中，促分裂素原活化蛋白激酶（mitogen-activated protein kinases，MAPK）信号通路与Smad2／3...目的研究体外低氧诱导小鼠心脏成纤维细胞（cardiac fibroblasts，CFs）向心脏肌成纤维细胞（cardiac myofibroblasts，CMFs）表型转换过程中，促分裂素原活化蛋白激酶（mitogen-activated protein kinases，MAPK）信号通路与Smad2／3蛋白磷酸化的关系。方法新生小鼠第1代CFs低氧（37℃、3％O2）无血清培养48h，免疫荧光检测α-SMA蛋白；新生小鼠CFs给予3种MAPK（ERK、JNK和p38）特异性抑制剂常氧培养1h，进行低氧培养30min，免疫印迹检测ERK、JNK、p38和Smad2／3蛋白磷酸化水平。结果①低氧显著上调新生小鼠CFs中α-SMA蛋白的表达；②低氧能显著地促进ERK、JNK和P38蛋白磷酸化，PD98059（ERK特异性抑制剂）、SP600125（JNK特异性抑制剂）和SB203580（P38特异性抑制剂）能抑制低氧诱导的ERK、JNK和P38蛋白的磷酸化；③PD98059（ERK特异性抑制剂）和SP600125（JNK特异性抑制剂）能抑制低氧诱导的Smad2／3蛋白的磷酸化，SB203580（P38特异性抑制剂）无此作用。结论①低氧可诱导小鼠CFs细胞发生表型转化为CMFs；②ERK和JNK信号通路能调控Smad2／3蛋白的磷酸化表达；③MAPK和Smad信号通路可能参与低氧诱导的小鼠CFs细胞的表型转化。展开更多
The PHB （polyhydroxybutyrate） films were reported recently as promising materials for tissue involving cultivation of dermoblasts, fibroblasts and connective tissue. In the present work, the authors studied PHB scaf...The PHB （polyhydroxybutyrate） films were reported recently as promising materials for tissue involving cultivation of dermoblasts, fibroblasts and connective tissue. In the present work, the authors studied PHB scaffolds for the cardiac tissue engineering, either in a form of thin membranes or electrospun fiber mats. The results show that cardiac cells of various origins can be successfully grown on PHB substrates, in the both forms： membrane and nanofiber matrix. Functioning of obtained tissue patches was tested by visual observation of contractions and with the aid of optical mapping, i.e., registration of excitation waves with fluorescent markers. The latter one allowed ensuring the fact that cultured cells represented electrophysiological syncytium, and the PHB scaffold showed its full compatibility with the excitability of cardiac cells.展开更多
Although microRNAs （miRNAs） have been intensively studied in cardiac fibrosis, their roles in drug-mediated anti-fibrotic therapy are still unknown. Previously, Pioglitazone attenuated cardiac fibrosis and increased...Although microRNAs （miRNAs） have been intensively studied in cardiac fibrosis, their roles in drug-mediated anti-fibrotic therapy are still unknown. Previously, Pioglitazone attenuated cardiac fibrosis and increased miR-711 experimentally. We aimed to explore the role and mechanism of miR-711 in pioglitazone-treated myocardial infarction in rats. Our results showed that pioglitazone significantly reduced collagen-I levels and increased miR-711 expression in myocardial infarction heart. Pioglitazone increased the expression of miR-711 in cardiac fibroblasts, and overexpression of miR-711 suppressed collagen-I levels in angiotensin II （Ang II）-treated or untreated cells. Transfection with antagomir-711 correspondingly abolished the pioglitazone-induced reduction in collagen-I levels. Bioinformatics analysis identified SP1, which directly promotes collagen-I synthesis, as the putative target of miR-711. This was confirmed by luciferase assay and western blot analysis. Additionally, increased SP1 expression was attenuated by pioglitazone in myocardial infarction heart. Furthermore, transfection of antago- mir-711 attenuated pioglitazone-reduced SP1 expression in cardiac fibroblasts with or without Ang II stimulation. We conclude that pioglitazone up-regulated miR-711 to reduce collagen-I levels in rats with myocardial infarction. The miR-711-SPl-collagen-I pathway may be involved in the anti-fibrotic effects of pioglitazone. Our findings may provide new strategies for miRNA-based anti-fibrotic drug research.展开更多
文摘目的研究体外低氧诱导小鼠心脏成纤维细胞（cardiac fibroblasts，CFs）向心脏肌成纤维细胞（cardiac myofibroblasts，CMFs）表型转换过程中，促分裂素原活化蛋白激酶（mitogen-activated protein kinases，MAPK）信号通路与Smad2／3蛋白磷酸化的关系。方法新生小鼠第1代CFs低氧（37℃、3％O2）无血清培养48h，免疫荧光检测α-SMA蛋白；新生小鼠CFs给予3种MAPK（ERK、JNK和p38）特异性抑制剂常氧培养1h，进行低氧培养30min，免疫印迹检测ERK、JNK、p38和Smad2／3蛋白磷酸化水平。结果①低氧显著上调新生小鼠CFs中α-SMA蛋白的表达；②低氧能显著地促进ERK、JNK和P38蛋白磷酸化，PD98059（ERK特异性抑制剂）、SP600125（JNK特异性抑制剂）和SB203580（P38特异性抑制剂）能抑制低氧诱导的ERK、JNK和P38蛋白的磷酸化；③PD98059（ERK特异性抑制剂）和SP600125（JNK特异性抑制剂）能抑制低氧诱导的Smad2／3蛋白的磷酸化，SB203580（P38特异性抑制剂）无此作用。结论①低氧可诱导小鼠CFs细胞发生表型转化为CMFs；②ERK和JNK信号通路能调控Smad2／3蛋白的磷酸化表达；③MAPK和Smad信号通路可能参与低氧诱导的小鼠CFs细胞的表型转化。
文摘The PHB （polyhydroxybutyrate） films were reported recently as promising materials for tissue involving cultivation of dermoblasts, fibroblasts and connective tissue. In the present work, the authors studied PHB scaffolds for the cardiac tissue engineering, either in a form of thin membranes or electrospun fiber mats. The results show that cardiac cells of various origins can be successfully grown on PHB substrates, in the both forms： membrane and nanofiber matrix. Functioning of obtained tissue patches was tested by visual observation of contractions and with the aid of optical mapping, i.e., registration of excitation waves with fluorescent markers. The latter one allowed ensuring the fact that cultured cells represented electrophysiological syncytium, and the PHB scaffold showed its full compatibility with the excitability of cardiac cells.
基金supported by the National Natural Science Foundation of China (81100164,31271212,81070196,81030001)the Research Fund for the Doctoral Program of Higher Education (20100001110101,20110001120015)the Program for New Century Excellent Talents in University,the Beijing Talents Foundation
文摘Although microRNAs （miRNAs） have been intensively studied in cardiac fibrosis, their roles in drug-mediated anti-fibrotic therapy are still unknown. Previously, Pioglitazone attenuated cardiac fibrosis and increased miR-711 experimentally. We aimed to explore the role and mechanism of miR-711 in pioglitazone-treated myocardial infarction in rats. Our results showed that pioglitazone significantly reduced collagen-I levels and increased miR-711 expression in myocardial infarction heart. Pioglitazone increased the expression of miR-711 in cardiac fibroblasts, and overexpression of miR-711 suppressed collagen-I levels in angiotensin II （Ang II）-treated or untreated cells. Transfection with antagomir-711 correspondingly abolished the pioglitazone-induced reduction in collagen-I levels. Bioinformatics analysis identified SP1, which directly promotes collagen-I synthesis, as the putative target of miR-711. This was confirmed by luciferase assay and western blot analysis. Additionally, increased SP1 expression was attenuated by pioglitazone in myocardial infarction heart. Furthermore, transfection of antago- mir-711 attenuated pioglitazone-reduced SP1 expression in cardiac fibroblasts with or without Ang II stimulation. We conclude that pioglitazone up-regulated miR-711 to reduce collagen-I levels in rats with myocardial infarction. The miR-711-SPl-collagen-I pathway may be involved in the anti-fibrotic effects of pioglitazone. Our findings may provide new strategies for miRNA-based anti-fibrotic drug research.
