右美托咪定缓解缺氧/复氧诱导的PC12细胞凋亡和炎症反应

Dexmedetomidine alleviates hypoxia/reoxygenation-induced apoptosis and inflammatory response of PC12 cells

目的探讨右美托咪定对缺氧/复氧(H/R)处理大鼠肾上腺嗜铬细胞瘤细胞细胞PC12损伤的影响及其分子机制。方法体外培养PC12细胞,将其分为Control组、H/R组、H/R+右美托咪定组、H/R+anti-miR-NC组、H/R+anti-miR-423-5p组、H/R+右美托咪定+miR-NC组、H/R+右美托咪定+miR-423-5p组,右美托咪定浓度为10μmol/L;MTT检测细胞活力;流式细胞术检测细胞凋亡;Western blot检测细胞凋亡相关蛋白的表达;ELISA检测TNF-α、IL-1β、IL-18、IL-10表达水平;RT-qPCR检测miR-423-5p的表达水平。结果与Control组比较,H/R组PC12细胞存活率显著降低(P<0.05),5、10、15、20μmol/L右美托咪定处理显著提高了PC12细胞存活率(P<0.05),且10μmol/L右美托咪定的PC12细胞存活率最高。与Control组比较,H/R组PC12细胞凋亡率、Bax蛋白水平和促炎因子TNF-α、IL-1β、IL-18水平升高,Bcl-2蛋白水平和抗炎因子IL-10水平降低(P<0.05)。右美托咪定预处理或抑制miR-423-5p表达可降低PC12细胞凋亡率、Bax蛋白水平和促炎因子TNF-α、IL-1β、IL-18水平,升高Bcl-2蛋白水平和抗炎因子IL-10水平(P<0.05)。H/R组miR-423-5p表达水平升高(P<0.05),右美托咪定处理可降低miR-423-5p表达(P<0.05),过表达miR-423-5p逆转了右美托咪定对H/R诱导PC12细胞凋亡和炎症反应的影响(P<0.05)。结论右美托咪定通过下调miR-423-5p缓解H/R诱导的PC12细胞损伤。

Objective To investigate the effects of dexmedetomidine on PC12 injury of rat adrenal pheochromocytoma cells treated with hypoxia/reoxygenation(H/R)and its molecular mechanism.Methods PC12 cells were cultured in vitro and divided into control group,H/R group,H/R+dexmedetomidine group,H/R+anti-miR-NC group,H/R+anti-miR-423-5p group,H/R+dexmedetomidine+miR-NC group,H/R+dexmedetomidine+miR-423-5p group;the dexmedetomidine concentration was 10μmol/L.MTT was used to detect cell viability.Flow cytometry was used to detect cell apoptosis.Western blot was used to detect the expression of apoptosis-related proteins.ELISA was used to detect the expression levels of TNF-α,IL-1β,IL-18 and IL-10.RT-qPCR was used to detect the expression level of miR-423-5p.Results Compared with control group,the survival rate of PC12 cells in H/R group was significantly decreased(P<0.05),the survival rate of PC12 cells treated with 5,10,15 and 20μmol/L dexmedetomidine was significantly increased(P<0.05),and the survival rate of PC12cells treated with 10μmol/L dexmedetomidine was the highest.Compared with control group,the apoptosis rate of PC12cells,Bax protein level and the levels of pro-inflammatory factors TNF-α,IL-1βand IL-18 were increased in H/R group,while the levels of Bcl-2 protein and anti-inflammatory factor IL-10 were decreased(P<0.05).Dexmedetomidine pretreatment or inhibition of miR-423-5p expression decreased the apoptosis rate of PC12 cells,Bax protein level and the levels of pro-inflammatory factors TNF-α,IL-1βand IL-18,and increased the levels of Bcl-2 protein and anti-inflammatory factor IL-10(P<0.05).The expression level of miR-423-5p in H/R group was increased(P<0.05),dexmedetomidine pretreatment reduced the expression of miR-423-5p(P<0.05),and overexpression of miR-423-5p reversed the effects of dexmedetomidine on H/R-induced apoptosis and inflammatory response of PC12 cells(P<0.05).Conclusion Dexmedetomidine alleviates H/R-induced PC12 cell damage by down-regulating miR-423-5p.