非马沙坦对2型糖尿病大鼠早期心肌S-腺苷同型半胱氨酸水解酶的调节作用

目的:探讨非马沙坦(FIM)在糖尿病心肌病(DCM)早期发生发展过程中的干预作用及对S-腺苷同型半胱氨酸水解酶(SAHH)的调节作用。方法:健康雄性SD大鼠,高脂饮食5周后,腹腔注射链脲佐菌素建立2型糖尿病大鼠模型,实验将大鼠分为正常对照(control)组、早期糖尿病模型(DM)组和DM+FIM组,DM+FIM组在造模成功后给予FIM灌胃处理。4周后,对各组动物进行血清学检测,包括空腹血糖(FBG)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)和空腹胰岛素(FINS)的水平,超声心动图检测心功能相关指标,高效液相色谱法(HPLC)检测同型半胱氨酸(Hcy)、S-腺苷甲硫氨酸(SAM)及S-腺苷半胱氨酸(SAH)的含量,Western blot检测各组大鼠心肌组织中SAHH等蛋白表达变化。结果:2型糖尿病大鼠模型造模成功率为84%,与DM组相比,DM+FIM组动物体重增加显著(P0.05),心脏指数、左心室指数、FBG和LDL-C明显降低(P0.05);超声心动图检测显示,与DM组相比,DM+FIM组大鼠射血分数明显升高(P0.05);HPLC检测结果显示,Hcy水平和SAM/SAH显著降低(P0.05);Western blot检测结果显示,相对于control组,DM组心肌组织中SAHH的表达显著升高,而DM+FIM处理组则下降。结论:SAHH及下游Hcy等因子的表达可能是早期糖尿病心肌病发生发展的重要作用机制,而非马沙坦可能通过抑制SAHH表达而减轻DCM。

Dynamic expression of S-adenosyl-L-homocysteine hydrolase under intervention of fimasartan in early stage of type 2 diabetic cardiomyopathy rats

AIM: To detect the changes of S-adenosyl-L-homocysteine hydrolase (SAHH) signaling pathway and related proteins under the intervention of fimasartan (FIM) in rats with diabetes mellitus (DM), and to explore the pathological mechanism of the occurrence and development of diabetic cardiomyopathy (DCM). METHODS: The type 2 diabetic rat model was established by injection of streptozocin after 5-week high-fat diet. The rats were randomly divided into control group, DM group, and DM+FIM group. Fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and fasting insulin (FINS) levels were tested. M-mode echocardiography was performed for determining the heart functions. High-performance liquid chromatography (HPLC) was used to detect homocysteine (Hcy), S-adenosylmethionine (SAM) and S-adenosyl-L-homocysteine (SAH). The alteration of SAHH in myocardium was determined by Western blot. RESULTS: The success rate of type 2 diabetic rat modeling was 84%. Compared with DM group, the body weight of the rats in DM+FIM group increased significantly (P<0.05), while cardiac index, left ventricular index, FBG and LDL-C were significantly reduced (P<0.05). The results of echocardiography showed that ejection fraction increased (P<0.05) in DM+FIM group. HPLC detection showed that the level of Hcy and the ratio of SAM/SAH were significantly reduced (P<0.05). The results of Western blot showed that the expression of SAHH in DM group was increased compared with control group, while that in DM+FIM group declined (P<0.01). CONCLUSION: The expression of SAHH, Hcy and other related factors may be important during the occurrence and development of early DCM, and FIM may play a role in this process as an inhibitor of SAHH.