七氟醚预处理对大鼠肺缺血再灌注时HMGB1/TLR4/NF-κB信号通路的影响

Effect of sevoflurane preconditioning on HMGB1/TLR4/NF-κB signaling pathway during lung ischemia-reperfusion in rats

目的评价七氟醚预处理对大鼠肺缺血再灌注时高迁移率族蛋白B1(HMGB1)/Toll样受体4(TLR4)/NF-κB信号通路的影响。方法雄性SD大鼠36只,8~10周龄,体重200~250 g,采用随机数字表法分为3组(n=12):假手术组(S组)仅游离右肺门,不阻断;肺缺血再灌注组(I/R组)采用阻断右肺门60 min、再灌注120 min的方法制备肺缺血再灌注损伤模型;七氟醚预处理组(SP组)吸入2.1%七氟醚30 min行预处理,停止吸入10 min时制备肺缺血再灌注损伤模型。于再灌注120 min时处死大鼠,取肺组织,光镜下观察病理学结果,并行肺损伤评分,测定湿重/干重(W/D)比值,采用ELISA法检测TNF-α含量,采用Western blot法测定HMGB1、TLR4和NF-κB的表达水平。结果与S组比较,I/R组和SP组肺损伤评分、肺组织W/D比值、TNF-α含量、HMGB1、TLR4和NF-κB的表达水平升高(P<0.05);与I/R组比较,SP组肺损伤评分、肺组织W/D比值、TNF-α含量、HMGB1、TLR4和NF-κB的表达水平降低(P<0.05),肺组织病理学损伤减轻。结论七氟醚预处理可能通过抑制HMGB1/TLR4/NF-κB信号通路,减轻大鼠肺缺血再灌注损伤。

Objective To evaluate the effect of sevoflurane preconditioning on high-mobility group box 1 protein (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway during lung ischemia-reperfusion(I/R)in rats. Methods Thirty-six clean-grade healthy male Sprague-Dawley rats, aged 8-10 weeks, weighing 200-250 g, were divided into 3 groups (n=12 each) using a random number table method: sham operation group (group S), lung I/R group (group I/R) and sevoflurane preconditioning group (group SP). The right pulmonary hilum was only isolated but not ligated in group S. Lung I/R was induced by clamping the right pulmonary hilum for 60 min followed by 120 min of reperfusion in anesthetized rats in group I/R.In group SP, 2.1% sevoflurane was inhaled for 30 min to perform sevoflurane preconditioning, and the lung I/R model was established at 10 min after the end of inhalation.The rats were sacrificed at 120 min of reperfusion, and the lungs were removed for examination of the pathological changes which were scored and for determination of wet to dry weight ratio (W/D ratio), content of tumor necrosis factor-alpha (TNF-α) in lung tissues (by enzyme-linked immunosorbent assay) and expression of HMGB1, TLR4 and NF-κB protein in lung tissues (by Western blot). Results Compared with group S, the pathological scores, W/D ratio and content of TNF-α were significantly increased, and the expression of HMGB1, TLR4 and NF-κB was up-regulated in I/R and SP groups (P<0.05). Compared with group I/R, the pathological scores, W/D ratio and content of TNF-α were significantly decreased, and the expression of HMGB1, TLR4 and NF-κB was down-regulated (P<0.05), and the pathological changes of lung tissues were significantly attenuated in group SP. Conclusion Sevoflurane preconditioning reduces lung I/R injury probably through inhibiting HMGB1/TLR4/NF-κB signaling pathway in rats.