圣草酚对高脂饮食诱导的糖尿病大鼠肝损伤的保护作用及机制探讨

The protective effect and mechanism of eriodictyol on the liver injury in diabetic rats induced by high-fat diet

关键词:  圣草酚  糖尿病  凋亡  原位末端标记技术  免疫组化  肿瘤坏死因子-α

Key words:  eriodictyol  diabetes  apoptosis  TUNEL  immunohistochemistry  TNF-α

摘要:

[目的] 探讨圣草酚对高脂饮食诱导的糖尿病（DM）大鼠肝损伤的保护作用，以及与氧化应激、胰岛素抵抗相关的机制探讨。[方法] 将50只雄性SD大鼠分为5组，即空白组、模型组、低剂量组（2.5 mg/kg）、中剂量组（5 mg/kg）、高剂量组（10 mg/kg），建立高脂饮食联合低剂量链脲佐菌霉素诱导的DM模型。评估胰岛素抵抗相关指标，包括空腹血糖（FBG）、空腹胰岛素（FINS）及胰岛素抵抗指数（HOMA-IR）；试剂盒检测肝功能生化指标水平，包括天门冬氨酸氨基转移酶（AST）、丙氨酸氨基转移酶（ALT）、低密度脂蛋白（LDL）、高密度脂蛋白（HDL）；苏木精-伊红（HE）染色观察肝组织病理形态；试剂盒检测氧化应激标志物水平，包括超氧化物歧化酶（SOD）、丙二醛（MDA）；原位末端标记技术（TUNEL）观察肝细胞凋亡情况；蛋白免疫印迹（Western Blot）法检测凋亡相关蛋白B淋巴细胞瘤-2（Bcl-2）、Bcl-2相关X蛋白（Bax）的表达；免疫组化法检测肿瘤坏死因子-α（TNF-α）水平。[结果] 与正常组相比，模型组大鼠出现DM典型症状“三多一少”，病理形态炎性浸润严重，各指标提示模型组大鼠造模成功。与模型组相比，各给药组胰岛素抵抗相关指标FBG、FINS、HOMA-IR降低；肝功能指标AST、ALT、LDL水平降低，HDL水平升高；氧化应激相关指标SOD活性增强，MDA含量减少；凋亡细胞及相关蛋白Bax、Bcl-2表达下降；炎症因子TNF-α阳性表达减少。[结论] 圣草酚改善高脂饮食诱导的DM肝损伤，发挥对DM大鼠肝脏的保护作用，其机制可能与调节转氨酶水平、促进脂质代谢、减轻氧化应激反应、减少肝细胞凋亡相关蛋白表达、缓解肝脏组织炎性浸润等途径有关。

Abstract:

[Objective] To explore the protective effect of Eriodictyol on the liver injury of diabetes mellitus (DM) rats induced by high-fat diet, and the mechanism related to oxidative stress and insulin resistance.[Methods] The 50 male SD rats were divided into five groups, normal blank group, model group(DW), low-dose group(DW+Eriodictyol 2.5 mg/kg), medium-dose group(DW+Eriodictyol 5 mg/kg), high-dose group(DW+Eriodictyol 10 mg/kg), a diabetes model induced by high-fat diet combined with low-dose streptozotocin was established. Assess related indicators of insulin resistance, fasting blood glucose (FBG), fasting insulin (FINS) and insulin resistance index (HOMA-IR);Kit to detect the level of biochemical indicators of liver function, aspartate aminotransferase (AST), alanine aminotransferase (ALT), low-density lipoprotein (LDL), high-density lipoprotein cholesterol (HDL);HE staining to observe the pathological morphology of liver tissue;Kit to detect the level of oxidative stress markers, superoxide dismutase(SOD), malondialdehyde(MDA);TUNEL to observe the apoptosis of liver cells;Western blot to detect the expression of apoptosis-related proteins Bax and Bcl-2;immunohistochemistry to detect the level of TNF-α.[Results] Compared with the normal group, the rats in the model group showed the typical symptoms of DM "three more and one less", and the pathological inflammatory infiltration was serious. Various indicators suggested that the rats in the model group. Compared with the model group, the insulin resistance related indexes FBG, FINS, and HOMA-IR of the administration group decreased. The liver function indexes AST, ALT, LDL levels decreased, and the HDL level increased;oxidative stress related indexes, SOD activity increased, and MDA content decreased;The expression of apoptotic cells and related proteins Bax/Bcl-2 decreased and the positive expression of inflammatory factor TNF-α decreased.[Conclusion] Eriodictyol can improve diabetic liver injury induced by high-fat diet and plays a protective effect on the liver of DM rats. The mechanism may be related to the regulation of transaminase levels, promotion of lipid metabolism, reducing oxidative stress response, reducing protein expression related to hepatocyte apoptosis, and alleviating inflammatory infiltration of liver tissue.