PLGA微球搭载鹿茸多肽联合BMSCs移植对坐骨神经损伤修复的作用及机制研究

Effects and Mechanism of VAP-loaded PLGA Microspheres Combined with BMSCs on Sciatic Nerve Injury Repair in Rats

目的探讨聚丙交酯-乙交酯(PLGA)微球搭载鹿茸多肽(VAP)联合骨髓间充质干细胞(BMSCs)移植对受损坐骨神经的修复作用及其相关机制。方法采用横断法复制大鼠坐骨神经损伤模型。将60只Wistar大鼠随机分为坐骨神经横断对照组(Control组)、VAP微球组(VAP组)、BMSCs移植组(BMC组)以及VAP微球联合BMSCs移植组(VAP+BMC组)。给予VAP(15 mg·mL^-1)、BMSCs(1×10^6·mL^-1)分别注射和联合注射后,观察3个月。采用坐骨神经功能指数(SFI)评估各组大鼠神经恢复情况;HE染色观察各组大鼠坐骨神经形态学变化;ELISA法检测各组大鼠血清中白介素-1β(IL-1β)、白介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)的含量;Western Blot法检测各组大鼠坐骨神经中IL-1β、IL-6和TNF-α的蛋白表达水平。结果与Control组比较,VAP组、BMC组和VAP+BMC组大鼠的SFI评分均明显升高(P<0.01),VAP+BMC组大鼠的神经修复速度更快;中性粒细胞及巨噬细胞表达明显较少,炎症反应减轻;各组大鼠血清及坐骨神经组织中IL-1β、IL-6和TNF-α的含量及蛋白表达水平均有不同程度降低,VAP+BMC组效果更明显(P<0.05,P<0.01)。结论PLGA微球搭载VAP联合BMSCs移植可修复受损的坐骨神经,其作用机制可能与抑制炎症因子的表达有关。

Objective To observe the effect of polylactide-glycolide acid(PLGA)microspheres loaded with velvet antler polypeptide combined with bone marrow mesenchymal stem cells(BMSCs)on injured sciatic nerve,and to explore its influence on inflammatory factor IL-1β,TNF-αand IL-6.Methods Cross-sectional method was used to establish models of rat sciatic nerve injury.A total of 60 rats were randomly divided into sciatic nerve transection control group(control group),VAP group(VAP),BMSCs transplantation group(BMC)and VAP microsphere combined with BMSCs transplantation group(VAP-BMC).The VAP and BMSCs were separately administered for three months.The sciatic nerve function index(SFI)was used to evaluate the neurological recovery of rats.HE staining was used to detect the morphological changes of peripheral nerves of rats.ELISA was used to detect the levels of IL-1β,IL-6 and TNF-αin serum of rats.Western Blot was used to detect the protein expression levels of IL-1β,IL-6 and TNF-αin the sciatic nerve of rats.Results Compared with the control group,the SFI of the VAP group,BMC group and the VAP-BMC group were significantly increased(P<0.01).The results of HE staining showed that compared with the control group,the expression of lymphocytes was less in administration groups and the inflammatory reaction was decreased.The results of ELISA and Western Blot showed that levels of IL-1β,IL-6 and TNF-αand protein expression in serum and sciatic nerve tissues of different administration groups were decreased at different degrees compared with control group,the effect of VAP+BMC showed better results(P<0.05 or P<0.01).Conclusion VAP-loaded PLGA combined with BMSCs can repair damaged sciatic nerve and its mechanism may be related to the inhibiting release of inflammatory factors.