贝母素乙通过调节Gas6/Axl信号通路对糖尿病大鼠心肌纤维化的影响

Effect of Peiminine B on myocardial fibrosis in diabetes rats by regulating Gas6/Axl signaling pathway

关键词:  贝母素乙  生长停滞特异性蛋白6/Axl信号通路  糖尿病  心肌纤维化

Key words:  Peiminine B  growth arrest-specific protein 6/Axl signaling pathway  diabetes  myocardial fibrosis

摘要:

[目的] 探讨贝母素乙（PMI）对糖尿病（DM）大鼠心肌纤维化及生长停滞特异性蛋白6（Gas6）/Axl信号通路的影响。[方法] 构建DM大鼠模型，将48只造模成功大鼠随机分为DM组、贝母素乙低、高剂量组（PMI-L、PMI-H组）、贝母素乙高剂量+通路抑制剂R428组（PMI-H+R428组），各12只，另取12只正常大鼠作对照组（Control组）；超声检查各组大鼠心功能指标；全自动血液分析仪检测各组大鼠空腹血糖（FBG）及血清肌酸激酶同工酶（CK-MB）、乳酸脱氢酶（LDH）水平；苏木精-伊红（HE）染色及Masson染色分别观察各组大鼠心肌组织病理变化及纤维化程度；TUNEL染色检测心肌组织细胞凋亡情况；免疫组化检测胶原蛋白Ⅰ（COLⅠ）、胶原蛋白Ⅲ（COLⅢ）表达；蛋白免疫印迹法检测Gas6、p-Axl/Axl表达。[结果] DM组较Control组心肌纤维断裂，心肌细胞排列紊乱，细胞肥大，细胞核固缩深染，炎性细胞浸润明显，细胞减少，蓝色胶原纤维沉积增多，且排列紊乱，分布弥散，左室舒张末期内径（LVEDD）、左室收缩末期内径（LVESD）和FBG、CK-MB、LDH水平及COLⅠ、COLⅢ表达升高，LVFS及Gas6、p-Axl/Axl表达降低（P<0.05）；PMI-L、PMI-H组较DM组心肌纤维排列相对整齐，细胞形态相对正常，炎性细胞浸润减少，细胞增多，纤维化现象减少，蓝色胶原纤维沉积减少，且细胞排列相对整齐，LVEDD、LVESD和FBG、CK-MB、LDH水平及COLⅠ、COLⅢ表达降低，LVFS及Gas6、p-Axl/Axl表达升高（P<0.05）；PMI-H+R248组较PMI-H组心肌组织病理损伤加重，炎性细胞浸润及心肌组织纤维化明显，蓝色胶原纤维沉积明显增多，LVEDD、LVESD和FBG、CK-MB、LDH水平及COLⅠ、COLⅢ表达升高，LVFS及Gas6、p-Axl/Axl表达降低（P<0.05）。[结论] 贝母素乙可抑制DM大鼠心肌纤维化，其作用机制与激活GAS6/Axl信号通路有关。

Abstract:

[Objective] This study was designed to investigate the effects of Peiminine B（PMI） on myocardial fibrosis and growth arrest-specific protein 6（Gas6）/Axl signaling pathway in diabetes（DM） rats. [Methods] We constructed a DM rat model and randomly divided the successfully modeled rats into a DM group，a low-dose and high-dose PMI group（PMI-L，PMI-H group），and a high-dose PMI+pathway inhibitor R428 group（PMI-H+R428 group），with 12 rats in each group. Additionally，12 normal rats were regarded as the control group. Ultrasound was applied to examine the cardiac function indicators of rats in each group. An automatic blood analyzer was applied to detect fasting blood glucose（FBG） and serum creatine kinase isoenzyme（CK-MB），and lactate dehydrogenase（LDH） levels were detected in rats in each group. HE staining and Masson staining were applied to observe the pathological changes and fibrosis degree of myocardial tissue of rats in each group. TUNEL staining was applied to detect apoptosis in myocardial tissue cells. Immunohistochemistry was applied to detect the expression of collagen I（COL I） and collagen Ⅲ（COL Ⅲ）. Immunoblotting was applied to detect the expression of Gas6 and p-Axl/Axl. [Results] Compared with the Control group，the DM group had myocardial fiber rupture，disordered arrangement of myocardial cells，cell hypertrophy，nuclear pyknosis and deep staining，obvious infiltration of inflammatory cells，decreased cell count，increased deposition of blue collagen fibers，and disordered arrangement with scattered distribution，the LVEDD，LVESD，levels of FBG，CK-MB，LDH，and expression of COL I and COL Ⅲ elevated，the expression of LVFS and Gas6，p-Axl/Axl reduced（P<0.05）. The arrangement of myocardial fibers in the PMI-L and PMI-H groups was relatively neat compared to the DM group，with relatively normal cell morphology，reduced inflammatory cell infiltration，increased cell count，reduced fibrosis，reduced deposition of blue collagen fibers，and relatively neat cell arrangement，the LVEDD，LVESD，levels of FBG，CK-MB，LDH，and expression of COL I and COL Ⅲ reduced，the expression of LVFS and Gas6，p-Axl/Axl increased（P<0.05）. The pathological damage to myocardial tissue in the PMI-H+R248 group was more severe than that in the PMI-H group，with obvious infiltration of inflammatory cells and fibrosis of myocardial tissue，the deposition of blue collagen fibers was increased，the LVEDD，LVESD，levels of FBG，CK-MB，LDH，and expression of COL I and COL Ⅲ increased，the expression of LVFS and Gas6，p-Axl/Axl reduced（P<0.05）. [Conclusion] Peiminine B can inhibit myocardial fibrosis in diabetes rats，and its mechanism is related to the activation of GAS6/Axl signaling pathway.