【摘要】 目的探讨微小RNA21(miR-21)对博莱霉素诱导的大鼠肺纤维化的影响及相关机制。方法收集特发性肺纤维化(IPF)患者及正常人的外周血各20份,采用荧光实时定量PCR检测miR-21表达。将45只SD大鼠随机分为对照组、miR-21激动剂(miR-21agomir)和miR-21拮抗剂(miR-21antagomir)组,每组15只。经气管内注入博莱霉素A5建立肺纤维化模型后,分别给予生理盐水、miR21 agomir、miR21 antagomir尾静脉注射,第28天处死所有大鼠。取出肺组织,行HE和Masson染色,通过荧光实时定量PCR和Western blot法分别检测含1型血小板结合蛋白基序的解聚蛋白样金属蛋白酶(ADAMTS-1)、1型胶原蛋白(Col1)、Col3 mRNA与蛋白表达,分离血清,ELISA检测血清1型前胶原蛋白羧基端前肽(P1CP)和3型前胶原蛋白氨基端前肽(P3NP)的含量。结果 IPF患者外周血miR-21表达水平明显高于正常人。miR-21 agomir组大鼠肺泡炎和肺纤维化程度明显重于对照组,而miR-21 antagomir组大鼠肺泡炎和肺纤维化程度显著轻于对照组。与对照组相比,miR-21 agomir组ADAMTS-1mRNA与蛋白表达水平降低,Col1、Col3的mRNA与蛋白表达水平及血清P1CP、P3NP水平均增加。但miR-21 antagomir组ADAMTS-1 mRNA与蛋白表达水平较对照组升高,Col1、Col3的mRNA与蛋白表达水平及血清P1CP、P3NP含量较对照组减少。结论 miR-21促进博莱霉素诱导的大鼠肺纤维化进展,其机制可能与下调ADAMTS-1表达及随后增加肺组织Col1、Col3含量有关。更多还原

【Abstract】 Objective To observe the effect of miR-21 on bleomycin-induced pulmonary fibrosis in rats,and explore the related mechanism. Methods Peripheral blood was collected from idiopathic pulmonary fibrosis( IPF) patients( n = 20) and healthy adults( n = 20). Fluorescence quantitative real-time PCR was then used to measure miR-21 expression. Forty-five SD rats were randomly divided into control group,miR-21 agomir group and miR-21 antagomir group. Each group included15 rats. After establishment of pulmonary fibrosis models by intratracheal administration with bleomycin A5,rats in control group,miR-21 agomir group and miR-21 antagomir group were injected at caudal vein with normal saline,miR21 agomir and miR21 antagomir,respectively. All rats were sacrificed on day 28 after modeling. Subsequently,the pulmonary tissues were removed for HE and Masson staining. The mRNA and protein expressions of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif( ADAMTS-1), collagen type 1( Col1) and collagen type 3( Col3) were detected by fluorescence quantitative real-time PCR and W estern blotting. Serum was separated to exam ine procollagen type 1carboxyterminal propeptide( P1CP) and procollagen type 3 aminoterminal propeptide( P3NP) concentrations by ELISA.Results The level of miR-21 in peripheral blood was higher in IPF patients than in healthy adults. The alveolitis and pulmonary fibrosis extent in miR-21 agomir group was heavier than that in the control group. However,the alveolitis and pulmonary fibrosis extent in miR-21 antagomir group was improved when compared with the control group. In comparison with the control group,ADAMTS-1 mRNA and protein expression was significantly downregulated,whereas the mRNA and protein expressions of Col1 and Col3 were significantly upregulated and serum P1 CP and P3 NP concentrations were elevated in miR-21 agomir group. On the contrary,the level of ADAMTS-1 mRNA and protein expression in miR-21 antagomir group was higher than that in the control group; the levels of Col1 and Col3 mRNA and protein as well as serum P1 CP and P3 NP concentrations in miR-21 antagomir group were lower than those in the control group. Conclusion miR-21 promotes the progression of bleomycin-induced pulmonary fibrosis in rats. The mechanism is associated with downregulation of ADAMTS-1expression and subsequent increase of pulmonary Col1 and Col3 contents.更多还原