丙泊酚对TNF-α诱导的小胶质细胞HMGB1表达的调控作用

The regulating effect of propofol on the expression of HMGB1 induced by TNF-α in microglia

目的:研究丙泊酚对TNF-α诱导的小胶质BV-2细胞高迁移率族蛋白B1(HMGB1)表达的影响。方法:用不同浓度(5、10、20、50、100、150、200μmol/L)的丙泊酚处理细胞后进行MTT实验检测细胞增殖;用不同浓度(5、10、20ng/mL)的TNF-α处理细胞后进行RT-qPCR和Westernblot检测HMGB1的表达;设立对照组、TNF-α(20ng/mL)组、TNF-α(20ng/mL)+丙泊酚(10、20、50μmol/L)组,丙泊酚干预TNF-α处理的细胞进行RT-qPCR和Westernblot检测HMGB1的表达和p38的磷酸化;利用siRNA沉默p38表达后再用丙泊酚处理,RT-qPCR和Westernblot检测HMGB1的表达。结果:高浓度丙泊酚(150、200μmol/L)抑制小胶质细胞增殖;与对照组比,经TNF-α刺激后小胶质细胞HMGB1表达增高;与TNF-α组比较,TNF-α+丙泊酚组HMGB1的表达明显降低,并呈剂量依赖性(P<0.05);沉默p38表达可抑制TNF-α诱导小胶质细胞HMGB1的表达(P<0.05);在沉默p38后再用丙泊酚处理,与单沉默p38比较,HMGB1的表达差异无统计学意义(P>0.05)。结论:丙泊酚可通过p38的激活调控TNF-α诱导小胶质细胞的HMGB1表达,从而影响脑损伤晚期炎症反应。

Objective： To investigate the effect of propofol on the expression of HMGB1 of microglia BV-2 cells induced by TNF-α. Methods： MTT was used to detect cell proliferation of microglia treated by propofol in different concentrations （5, 10, 20, 50, 100, 150 and 200 μmol/L）. Control group, TNF-α （20 ng/mL） group, and TNF-α （20 ng/mL） ＋ propofol （10, 20 and 50 μmol/L） group were set up. The expression of HMGB1 and the phosphorylation of p38 in microglia were detected by RT-qPCR and Western blot after microglia was pretreated with propofol （10, 20 and 50 μmol/L） and then stimulated with TNF-α. Utilizing siRNA to silence p38 before it was treated with propofol and the expression of HMGB1 was examined by RT-qPCR and Western blot. Results：High concentration of propofol （150 and 200 μmol/L） inhibited the proliferation of microglial cells. Compared with the control group, the expression of HMGB1 was increased after TNF-α stimulation. The expression of HMGB1 in TNF-α＋propofol group was significantly reduced and presented dosage dependence compared with TNF-α group. Silencing p38 inhibited the TNF-α-induced expression of HMGB1 in microglia. There was no significant difference in HMGB1 expression between the group with silenced p38 alone and the propofol-treated group after silencing p38. Conclusion： Propofol can be used to regulate the expression of HMGB1 of microglial cells through activating p38 and thus affecting the advanced inflammatory response to brain injury.