糖痹康对糖尿病周围神经病变大鼠脂代谢及坐骨神经超微结构的影响

Effects of Chinese herbal compound Tangbikang on the lipid metabolism and ultrastructure of sciatic nerve of diabetic peripheral neuropathy rats

目的:观察中药复方糖痹康对糖尿病周围神经病变(DPN)大鼠脂代谢和坐骨神经超微结构的影响。方法:采用高脂饲料和小剂量链脲佐菌素(STZ)诱发2型糖尿病大鼠动物模型,用不同剂量的糖痹康灌胃,并与甲钴胺对照,16周后腹主动脉取血及大鼠一侧坐骨神经,用电镜观察其超微结构,采用酶法测定大鼠血清总胆固醇(TC)和甘油三酯(TG);免疫比浊法测定大鼠血清高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C);铜试纸显色法检测大鼠血清游离脂肪酸(NEFA)。结果:与正常组比较,模型组HDL-C含量均显著降低(P<0.01),TG、TC、LDL-C、NEFA均显著升高(P<0.01)。与模型组比较,糖痹康及甲钴胺组HDL-C的含量均显著升高(P<0.01),TG、TC、LDL-C、NEFA含量均显著降低(P<0.01)。电镜结果显示,正常组大鼠坐骨神经横切面髓鞘结构完整、致密、均匀;模型组大鼠坐骨神经横切面髓鞘的板层结构发生严重分离,各层间排列紊乱,出现大量空泡及裂隙;各给药组坐骨神经中空泡及裂隙均显著降低,但髓鞘仍未恢复板层状结构,线粒体及粗面内质网结构正常,出现结构完整的雪旺细胞。结论:糖痹康能改善DPN大鼠血脂及降低其血清NEFA水平,同时其对坐骨神经髓鞘、轴索等具有修复作用。

Objective： To explore the effects of Chinese herbal compound Tangbikang on the lipid metabolism and ultrastructure of sciatic nerve of diabetic peripheral neuropathy rats. Methods： The experimental type 2 diabetes mellitus rat model was induced by feeding high fat forage and injecting small dose of streptozotocin（STZ）. Tangbikang groups were given Tangbikang with different doses by gavage, and the control group was given mecobalamin. Blood plasma was collected by abdominal aortic and one side of sciatic nerves was cutting-up after 16 weeks. Ultrastructure of rat’s sciatic nerve was observed by electron microscopy. The serum total cholesterol（TC） and triglyceride（TG） were determined by the enzyme analysis method. The high-density lipoproteincholesterol（HDL-C） and low-density lipoproteincholesterol（LDL-C） were determined byimmunoturbidimetry method. The non-esterified fatty acid（NEFA） level of rat’s serum was determined by the method of Cul test paper. Results： Compared with normal group, the content of HDL-C in model group was significantly reduced（P〈0.01）, and the contents of TG, TC, LDL-C and NEFA were significantly increased（P〈0.01）. Compared with model group, the contents of HDL-C in Tangbikang groups and control group were significantly increased, and the contents of TG, TC, LDL-C and NEFA were significantly reduced. Electron microscopy results showed that the sciatic nervemyelin sheath was structural integrity, densification and well-distributed in normal group, while for the sciatic nervemyelin sheath in model group, serious separation of lamellar structure, a disordered arrangement between each layer and a large number of vacuoles and gaps could be seen. The vacuoles and gaps of sciatic nerve were significantly reduced in Tangbikang group, but the lamellar structure was also abnormal. The structures of mitochondria and rough endoplasmic reticulum were in normality, and structural integrity schwann cell was observed. Conclusion： Chinese herbal compound Tangbikang could regulate blood fat and reduce level of serum free fatty acids, and it could also repair myelin sheath and axonal of the sciatic nerve.