硫化氢通过p38MAPK和TGF-β1影响糖尿病小鼠心肌纤维化的研究

Hydrogen sulfide influences myocardial fibrosis in diabetic mice by p38MAPK and TGF-β1

摘要:

摘要：目的  探讨硫化氢（H2S）对糖尿病小鼠心肌组织中p38丝裂原活化蛋白激酶（p38MAPK）、转化生长因子-β1（TGF-β1）及Ⅰ型胶原蛋白（CollagenⅠ）表达的影响，以及对糖尿病心肌纤维化的保护作用。方法  18只雄性C57BL/6J小鼠随机分为正常对照组（NC组）、糖尿病对照组（ALX组）、H2S治疗组（ALX+H2S组），每组6只。采用四氧嘧啶（ALX）200 mg/kg腹腔注射复制糖尿病小鼠模型；模型复制成功后，NC组和ALX组每天自由饮用自来水；ALX+H2S组自由饮用浓度为90 μmol/L的NaHS（H2S供体）溶液。8周后取材，监测空腹血糖、血脂；苏木精-伊红染色法观察心肌组织形态学变化；采用Western blot检测p-p38MAPK、TGF-β1及CollagenⅠ蛋白表达；实时定量荧光聚合酶链反应检测p38MAPK和TGF-β1 mRNA的表达。结果  与NC组比较，ALX组血糖、血脂升高（P <0.05），心肌组织胶原表达量增加，心肌间质出现明显纤维化，p-p38MAPK、TGF-β1及CollagenⅠ蛋白表达增高（P <0.05），p38MAPK和TGF-β1 mRNA表达增加（P <0.05）；糖尿病小鼠经H2S干预，血糖、血脂改善（P <0.05），心肌间质胶原纤维明显减少，p-p38MAPK、TGF-β1及CollagenⅠ蛋白表达下降（P <0.05），p38MAPK和TGF-β1 mRNA表达减少（P <0.05）。结论  H2S可改善糖尿病小鼠血糖、血脂及心肌纤维化，可能与调节p38MAPK和TGF-β1的表达有关。

Abstract:

Abstract: Objective To study the effect of exogenous hydrogen sulfide (H2S) on the expressions of p38 mitogen-activated protein kinase (p38MAPK) and transforming growth factor-beta1 (TGF-β1) and on the protection of diabetic myocardial fibrosis. Methods Eighteen male adult C57BL/6J mice were randomly divided into normal control group (NC group), diabetes mellitus group (ALX group), and diabetes mellitus treated with H2S group (ALX+H2S group) with six mice in each group. The diabetic mouse model was established by intra-peritoneal injection (i.p.) of 200 mg/kg ALX. The mice in the normal control and ALX groups drank tap water freely everyday. The mice of the ALX+H2S group freely drank NaHS (H2S donor) solution at a concentration of 90 μmol/L. After 8 weeks, fasting blood glucose and serum lipid were tested. The pathological changes of myocardial fibers were observed by HE staining. The expressions of p-p38MAPK, TGF-β1 and collagen Ⅰ were detected using Western blot. The expressions of p38MAPK mRNA and TGF-β1 mRNA were tested by qRT-PCR. Results Compared with the NC group, the fasting blood glucose and serum lipid increased (P < 0.05), the expression of collagen in myocardium increased and there was apparent myocardial interstitial fibrosis; the expressions of p-p38MAPK and TGF-β1 proteins and collagen Ⅰ increased (P < 0.05), the mRNA expressions of p38MAPK and TGF-β1 increased (P < 0.05) in the ALX group. After the intervention of H2S, the fasting blood glucose and serum lipid were improved (P < 0.05), the collagen fibers in the myocardial interstitium apparently decreased, the protein expressions of p-p38MAPK, TGF-β1 and collagen Ⅰwere decreased (P < 0.05), the mRNA expressions of p38MAPK and TGF-β1 were decreased (P < 0.05). Conclusions H2S can ameliorate fasting blood glucose, serum lipid and myocardial fibrosis in diabetic mice, which might be related to the regulation of p38MAPK and TGF-β1 expressions.