20-羟基蜕皮甾酮对1型糖尿病小鼠降糖作用的研究

摘要

Objective To study the glucose-lowering effect of 20-hydroxyecdysone(20E)on type 1 diabetes mellitus induced streptozocin(STZ)and its mechanism. Methods Forty-five mice were randomly divided into three groups,with 15 mice in each group. Animals of type 1 diabetes mellitus were induced by injection of STZ with a concentration of 150 mg / kg,then 20E treatment group was treated with 20E solution at a concentration of 5 mg / kg and with similar volume saline solution in normal group and model group,respectively. The histopathological changes of liver were examined using hematoxylin /eosin,the serum glucose and liver glycogen contents were measured,the expression levels of glucokinase (GK)and tumor necrosis factor-α(TNF-α)were detected by real-time PCR. Results Compared with that of mode group,liver histopathological study showed 20E treatment results in protective role. After 20E treatment,the serum glucose levels decreased by 92. 7%(P < 0. 01),and liver glycogen contents increased by 64. 1%(P < 0. 05). Real-time PCR results revealed the levels of GK mRNA increased by 107. 3%(P < 0. 01),and TNF-α levels decreased by 68. 7%(P < 0. 05). Conclusions 20E can re-duce blood glucose in type 1 diabetic mice,and its mechanism may be related to induction of hepatic GK expression,increased liver glycogen reserves and enhance liver protective effect.%目的：探讨20-羟基蜕皮甾酮（20E）对1型糖尿病小鼠降糖作用及相关机制。方法将45只小鼠随机分三组，每组15只，用150 mg/ kg 腹腔注射链脲佐菌素（STZ）造模，正常对照组和1型糖尿病（DM）组小鼠灌服蒸馏水10 ml/ kg；20E 治疗组按5 mg/ kg 剂量灌服20E。药物干预3周后，观察肝脏形态学改变，测定血糖和肝脏糖原含量，分析葡萄糖激酶（GK）和肿瘤坏死因子-α（TNF-α）的表达。结果与模型组相比，20E 处理后肝细胞损伤程度减轻；血糖浓度比模型组降低了92.7%（P <0.01），肝脏糖原含量增加了64.1%（P <0.05）；Real-time PCR 结果显示，20E 处理后 GKmRNA 水平增加了107.3%（P <0.01），TNF-α表达水平降低了68.7%（P <0.05）。结论20E 具有降低1型糖尿病小鼠血糖的作用，其机制可能与诱导肝脏 GK 表达、增加肝脏糖原储备和增强肝脏保护作用有关。