α7n型乙酰胆碱能受体在小胶质细胞中下调炎症水平的作用及其机制研究

The anti-inflammatory role ofα7 nicotinic acetylcholine receptor in microglial cells and its mechanisms

目的小胶质细胞在中枢神经系统的炎症相关疾病中发挥重要作用,旨在研究在炎症环境中α7 n型乙酰胆碱能受体的抗炎作用及机制。方法应用PNU282987激动α7 n型乙酰胆碱能受体,应用脂多糖(LPS)造成细胞的炎症模型,通过实时定量PCR技术检测BV2细胞的炎症因子IL-1β、IL-6、TNF-α及M1型巨噬细胞标记物CD68、CD86与M2型巨噬细胞标记物CD206、Arg1的mRNA水平,通过细胞免疫荧光检测M1型及M2型巨噬细胞的比例,通过Western blot技术检测自噬相关蛋白的表达。结果在LPS的刺激下,小胶质细胞中促炎因子IL-1β、IL-6、TNF-α的mRNA水平显著增加、M1型巨噬细胞比例显著增加、自噬水平显著上调,而应用PNU282987激动α7 n型乙酰胆碱能受体极大地降低了促炎因子IL-1β、IL-6、TNF-α的mRNA水平、增加M2型巨噬细胞比例、降低M1型巨噬细胞比例,并进一步上调小胶质细胞的自噬水平。结论激动α7 n型乙酰胆碱能受体可以发挥抑制小胶质细胞炎症反应的作用,其作用的实现依赖于调节小胶质细胞M1型和M2型巨噬细胞比例和上调自噬水平。

Objective To investigate the anti-inflammatory role ofα7 nicotinic acetylcholine receptor(α7nAChR)under inflammatory stress and its mechanisms.Methods PNU282987 was used for the activation ofα7nAChR and LPS was administrated as inflammatory stressor.Realtime PCR was used for the detection of IL-1β,IL-6,TNF-α,M1 macrophage marker CD68,CD86 and M2 macrophage marker CD206,Arg1.Cell immunofluorescence was used for the detection of M1/M2 ratio and Western blot was applied for the detection of autophagy-related proteins.Results Under the stimulation of LPS,the mRNA levels of proinflammatory cytokines IL-1β,IL-6 and TNF-α,the proportion of M1 macrophage and autophagy process were increased in BV2 microglial cells.However,the administration of PNU282987 significantly decreased the mRNA levels of IL-1β,IL-6 and TNF-αand the proportion of M1 macrophage while increased the proportion of M2 macrophage and the level of autophagy process.Conclusion Activatingα7nAChR plays an anti-inflammatory role in microglial cells under inflammatory stress due to the regulation of M1/M2 macrophage ratio and increase of autophagy level.