摘要
目的:探究8周跑台运动对T2DM小鼠心肌细胞纤维化的影响及其分子机制。方法:8只m/m小鼠为对照组,32只db/db小鼠随机分为:对照组、模型组、运动干预组、单纯抑制剂组和运动联合抑制剂干预组,每周定期监测小鼠空腹血糖。8周后,检测小鼠血脂:TG和TC;采用Masson染色观察小鼠心肌纤维化程度、免疫荧光染色观察CollagenⅠ、α-SMA的表达情况。用Western Blot检测纤维化、炎症、焦亡、p38MAPK等相关蛋白表达水平。结果:模型组空腹血糖、TG和TC(P<0.0001)及CollagenⅢ(P<0.05)、TGF-β1(P<0.01)的表达较对照组均显著上升;Masson染色显示,相比模型组,其余各组心肌细胞排列紊乱、结构模糊等问题明显改善,组织间质和血管周围蓝色胶原纤维明显减少,免疫荧光染色显示其余各组CollagenⅠ和α-SMA表达量明显降低,纤维化相关蛋白表达水平均显著下降;运动干预组炎症及焦亡相关蛋白表达水平较模型组显著降低。与模型组相较,运动干预组及单纯抑制剂组p38MAPK磷酸化水平显著降低(P<0.05、P<0.01),然而,联合干预后其磷酸化水平未进一步下降;与模型组相比,单纯抑制剂组NLRP3、GSDMD-N表达水平明显降低(P<0.05),同时联合干预进一步抑制小鼠Caspase-1(P<0.05)、Cleaved-Caspase-1(P<0.05)、GSDMD-N(P<0.001)的表达。结论:8周跑台运动可以明显改善db/db小鼠心肌纤维化,其机制可能是通过降低p38MAPK磷酸化水平,减轻心肌细胞焦亡现象,从而改善db/db小鼠心肌纤维化,跑台运动联合SB203580可更进一步减轻焦亡反应。
Objective:To explore the effect of 8-week treadmill exercise on myocardial fibrosis in mice with T2DM and its molecular mechanism.Method:Eight m/m mice were used as the control group,and 32 db/db mice were randomly divided into control group,model group,exercise intervention group,inhibitor alone group and exercise combined with inhibitor intervention group.Fasting blood glucose was monitored weekly.After 8 weeks,triglycerides(TG)and total cholesterol(TC)were measured.Masson staining was used to observe the degree of myocardial fibrosis,and immunofluorescence staining was used to observe the expression of CollagenⅠandα-SMA.Western Blot was used to detect the expression levels of fibrosis,inflammation,pyroptosis and p38MAPK related proteins.Result:The model group showed a significant increase in fasting blood glucose,TG and TC(P<0.0001),Collagen Ⅲ(P<0.05) and TGF- β1(P<0.01) expression compared with control group. Compared to the modelgroup, Masson staining in the other groups showed a significant improvement in disordered myocardial cell arrangement and a decrease in blue collagen fibers between the interstitial tissue and perivascular tissue;immunofluorescence staining also showed that the expression levels of Collagen I and α-SMA and the expression levels of fibrosis-related proteins were significantly decreased in these groups. The expression levels of inflammation and pyroptosis related proteins in the exercise intervention group were significantly lower than those inthe model group. Compared to the model group,the phosphorylation level of p38MAPK in the exercise intervention group and the simple inhibitor group was significantly decreased(P<0.05,P<0.01),but the phosphorylation level was not further decreased after the combined intervention. Compared to the model group,the expression levels of NLRP3 and GSDMD-N in the single inhibitor group were significantly decreased(P<0.05),and the combined intervention further inhibited the expression of Caspase- 1(P<0.05),Cleaved-Caspase- 1(P<0.05),and GSDMD-N(P<0.001).Conclusion: Eight- week treadmill exercise can significantly improve myocardial fibrosis in db/db mice. Themechanism may reduce the phosphorylation of p38MAPK and pyroptosis of cardiomyocytes,thus improvingmyocardial fibrosis in db/db mice. The combination of treadmill exercise and SB203580 can further reduce pyroptosis.
作者
朱悦
张蒙
张源源
牛梦竹
张宝文
寇现娟
ZHU Yue;ZHANG Meng;ZHANG Yuanyuan(Hubei Key Laboratory of Exercise Training Monitoring,College of Sports Medicine,Wuhan Institute of Physical Education and Sport,Wuhan,430079)
出处
《中国康复医学杂志》
CAS
CSCD
北大核心
2024年第10期1417-1429,共13页
Chinese Journal of Rehabilitation Medicine
基金
国家自然科学基金项目(81601228)
教育部人文社会科学研究规划基金项目(21YJA890014)。
