糖络宁对糖尿病周围神经病变大鼠PERK-CHOP-Caspase-12通路的影响

摘要

目的 观察糖络宁对糖尿病周围神经病变(diabetic peripheral neuropathy,DPN)大鼠坐骨神经内质网应激相关PERK-CHOP-Caspase-12通路的调节作用.方法 选用8周龄雄性SD大鼠,除空白对照组外,采用高脂饲料致高血脂联合链脲佐菌素腹腔注射诱导高血糖致DPN大鼠模型.将高脂高糖大鼠随机分为模型对照组、阳性药(氧化三甲胺)对照组、糖络宁低剂量组和糖络宁高剂量组,连续给药12周.给药过程中,动态监测大鼠血糖、血脂,确保糖尿病造模成功.12周后采用免疫荧光法检测坐骨神经中葡萄糖调节蛋白(glucose regulatory protein 78kD,GRP78)、C/EBP同源蛋白(C/EBP-homologous protein,CHOP)、蛋白激酶样内质网激酶(PKR-like ER kinase,PERK)、caspase-12和caspase-3的表达.结果 与空白对照组比较,模型对照组坐骨神经中GRP78、CHOP、PERK、Caspase-12和Caspase-3的表达均显著升高(P<0.01或P<0.05);与模型对照组比较,糖络宁低剂量组和高剂量组GRP78表达显著升高(P<0.01),CHOP、PERK、Caspase-12和Caspase-3表达明显降低(P<0.01或P<0.05).结论 糖络宁防治DPN的作用机制与调节坐骨神经中内质网应激相关的PERK-CHOP-Caspase-12通路相关蛋白表达而抑制细胞凋亡有关.%Objective To observe the effect of Tangluoning on PERK-CHOP-Caspase-12 pathway of endoplasmic reticulum stress ( ERS ) in sciatic nerve of diabetic peripheral neuropathy ( DPN ) rats. Methods The rat model was induced by high-fat diet and intraperitoneal injected with streptozocin. Rats with hyperlipidemia and hyperglycemia were randomly divided into model control group, positive control ( trimethylamine oxide) group, low dose of Tangluoning group and high dose of Tangluoning group, and then successively administrate for 12 weeks. In the 12 weeks of administration process, blood glucose and blood lipid were dynamically monitored to ensure the success of diabetes model. After 12 weeks, immuno-fluorescence method was used to measure the expression of GRP78, CHOP, PERK, Caspase-12 and Caspase-3 in sciatic nerve. Results The expressions of GRP78, CHOP, PERK, Caspase-12 and Caspase-3 in sciatic nerve were significantly increased in model control group compared those in normal group (P<0. 01,P<0. 05). Compared with model control group, the expressions of GRP78 were increased (P<0. 01)while the expressions of CHOP, PERK, Caspase-12 and Caspase-3 were decreased in both low dose of Tangluoning group and high dose of Tangluoning group(P<0. 01,P<0. 05). Conclusion The prevention and treatment mechanism of Tangluoning on DPN may be related to inhibit sciatic nerve apoptosis by regulating PERK-CHOP-Caspase-12 pathway in endoplasmic reticulum stress.