槲皮素通过下调缓激肽受体B1表达减轻糖尿病大鼠神经病理性疼痛

Quercetin reduces neuropathic pain in diabetic rats by down-regulating theexpression of bradykinin receptor B1

目的:研究槲皮素通过下调缓激肽受体B1(BDKRB1)表达减轻糖尿病大鼠神经病理性疼痛的机制。方法:60只大鼠腹腔注射60 mg/kg链脲佐菌素建立糖尿病神经病理性疼痛(DNP)大鼠模型,采用随机数表法平均分为5组:模型组、槲皮素(100 mg/kg)组、BDKRB1过表达质粒组、空载质粒组、槲皮素(100 mg/kg)+BDKRB1过表达质粒组,另选12只大鼠腹腔注射等剂量生理盐水作为对照组。各组大鼠以药物分组干预处理后,检测大鼠机械性刺激痛觉、热刺激痛觉与冷刺激痛觉,比较各组机械性缩足阈值、冷刺激抬足时间、热敏潜伏期;免疫组织化学染色检测大鼠脊髓背根神经节淋巴细胞浸润情况,比较各组淋巴细胞功能相关抗原-1(LFA-1)阳性细胞比例;试剂盒测量大鼠血清炎症介质IL-17、环氧化酶-2(COX-2)、IL-18水平;RT-qPCR、Western blot分别检测大鼠脊髓背根神经节BDKRB1 mRNA及蛋白表达水平。结果:与对照组比较,模型组大鼠机械性缩足阈值、热敏潜伏期显著降低(P<0.05),冷刺激抬足时间、LFA-1阳性细胞比例、血清IL-17、COX-2及IL-18水平、BDKRB1mRNA及蛋白表达水平显著升高(P<0.05);与模型组、槲皮素+BDKRB1过表达质粒组分别比较,槲皮素组大鼠机械性缩足阈值、热敏潜伏期均升高(P<0.05),冷刺激抬足时间、LFA-1阳性细胞比例、血清IL-17、COX-2及IL-18水平、BDKRB1 mRNA及蛋白表达水平均降低(P<0.05);BDKRB1过表达质粒组大鼠机械性缩足阈值、热敏潜伏期均降低(P<0.05),冷刺激抬足时间、LFA-1阳性细胞比例、血清IL-17、COX-2及IL-18水平、BDKRB1 mRNA及蛋白表达水平均升高(P<0.05);空载质粒组大鼠各指标均无显著变化(P>0.05)。结论:槲皮素通过下调BDKRB1表达抑制炎症,减少淋巴细胞浸润,减轻糖尿病大鼠神经病理性疼痛症状。

Objective:To study the mechanism of quercetin reduces neuropathic pain in diabetic rats by down-regulating the expression of bradykinin receptor B1(BDKRB1).Methods:Sixty diabetic neuropathic pain(DNP)model rats were established by intraperitoneal injection of 60 mg/kg streptozotocinm,which were divided into 5 groups by the random number table method:model group,quercetin(100 mg/kg)group,BDKRB1 overexpression plasmid group,empty plasmid group and quercetin(100 mg/kg)+BDKRB1 overexpression plasmid group,another 12 rats were intraperitoneally injected with the same dose of normal saline as control group.After rats in each group were treated with drugs,mechanical stimulation pain,thermal stimulation pain and cold stimulation pain in rats were detected,and the mechanical paw withdrawal threshold,cold stimulation paw lift time,and heat sensitivity latency were compared in each group;infiltration of lymphocytes in dorsal root ganglion of the spinal cord in rats was detected by immunohisto-chemical staining,proportion of lymphocyte function-related antigen-1(LFA-1)positive cells in each group was compared;levels of rat serum inflammatory mediators IL-17,cyclooxygenase-2(COX-2)and IL-18 were measured by kits;and mRNA and protein expres-sion level of BDKRB1 in rat spinal dorsal root ganglia were detected by RT-qPCR and Western blot.Results:Compared with control group,mechanical paw withdrawal threshold and heat sensitivity latency of model group were significantly reduced(P<0.05),while the cold stimulation foot lift time,proportion of LFA-1 positive cells,serum IL-17,COX-2 and IL-18 levels,BDKRB1 mRNA and protein expression level were significantly increased(P<0.05);compared with model group and quercetin+BDKRB1 overexpression plasmid group,mechanical paw withdrawal threshold and heat sensitivity latency of quercetin group were significantly increased(P<0.05),while the cold stimulation foot lift time,proportion of LFA-1 positive cells,serum IL-17,COX-2 and IL-18 levels,BDKRB1 mRNA and protein expression level were significantly reduced(P<0.05);mechanical paw withdrawal threshold and heat sensitivity latency of BDKRB1 overexpression plasmid group were significantly reduced(P<0.05),while the cold stimulation foot lift time,pro-portion of LFA-1 positive cells,serum IL-17,COX-2 and IL-18 levels,BDKRB1 mRNA and protein expression level were significantly increased(P<0.05);there were no significant changes in the above indexes of rats in empty plasmid group(P>0.05).Conclusion:Quercetin inhibits inflammation,reduces lymphocyte infiltration,and reduces neuropathic pain symptoms in diabetic rats by down-regulating the expression of BDKRB1.