目的:探讨益气升陷活血方及其拆方对心梗后心衰低血压大鼠心肌Ⅰ、Ⅲ型胶原的影响。方法:采用大鼠心脏左冠状动脉结扎术,建立心衰模型,将LVEF值≤50%、尾动脉收缩压≤90 mm Hg的大鼠随机分为4组,即心衰低血压组、益气升陷活血方组、益...目的:探讨益气升陷活血方及其拆方对心梗后心衰低血压大鼠心肌Ⅰ、Ⅲ型胶原的影响。方法:采用大鼠心脏左冠状动脉结扎术,建立心衰模型,将LVEF值≤50%、尾动脉收缩压≤90 mm Hg的大鼠随机分为4组,即心衰低血压组、益气升陷活血方组、益气升陷组、活血化瘀组,灌胃干预8周。用免疫组化及RT-PCR检测心肌Ⅰ、Ⅲ型胶原,并实时定量PCR检测心肌Ⅰ、Ⅲ型胶原m RNA的含量。结果:与心衰低血压组比较,所有治疗组心肌Ⅰ、Ⅲ型胶原含量及m RNA的含量均降低(P<0.05);与活血化瘀治疗组比较,益气升陷组、全方治疗组,心肌Ⅰ、Ⅲ型胶原m RNA的含量均降低,全方治疗组更显著(P<0.05)。结论:全方治疗组、益气升陷组、活血化瘀组能减轻心梗后心衰大鼠心肌纤维化的程度,减少心肌Ⅰ、Ⅲ型胶原的含量,其中全方治疗组较益气升陷治疗组、活血化瘀治疗组的改善作用明显,益气升陷组次之。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
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.
