大鼠腹腔巨噬细胞高迁移率族蛋白B1诱生机制的初步探讨

Effect of lipopolysaccharide on stimulating high mobility group box-1 protein expression in peritoneal macrophages in rats and its potential signaling mechanism

目的 探讨腹腔巨噬细胞高迁移率族蛋白B1(HMGB1)诱生的分子机制。方法 取正常Wistar大鼠腹腔巨噬细胞置 2 4孔培养板中 (1× 10 6/孔 ) ,培养 3天后用内毒素 (LPS)刺激 ,观察LPS刺激与巨噬细胞HMGB1mRNA表达的时效关系及量效关系 ,同时观察氟达拉滨 (fludarabine,STAT1抑制剂 )及雷帕霉素 (rapamycin,STAT3抑制剂 )对HMGB1mRNA表达的影响。结果 LPS刺激可使大鼠腹腔巨噬细胞HMGB1mRNA表达明显上调 ,于攻击后 2 4～36h达峰值 ,至 4 8h减弱。LPS的刺激剂量为 75～10 0ng/ml时 ,HMGB1基因表达明显增强。经氟达拉滨和雷帕霉素处理均可明显下调HMGB1基因表达。结论 LPS可诱导大鼠腹腔巨噬细胞HMGB1mRNA表达 ,其诱生机制与Janus激酶 /信号转导子和转录激活因子 (JAK/STAT )途径密切相关。

Objective To investigate the effect of lipopolysaccharide (LPS) on stimulating high mobility group box-1 protein (HMGB1) mRNA expression in peritoneal macrophages in rats and its potential signaling mechanism. Methods Abdominal macrophages obtained from male Wistar rats were seeded on 24-well (1×10 6 cells/well) tissue culture plates. The cells were incubated for 3 days before they were stimulated with LPS, fludarabine (specific inhibitor of signal transducer and activator of transcription 1, STAT1), or rapamycin (specific inhibitor of signal transducer and activator of transcription 3, STAT3). After being stimulated, macrophages were denatured directly in tissue culture plates to determine HMGB1 mRNA expression. The time-dependent and dose-dependent responses between LPS stimulation and HMGB1 mRNA expression were analyzed, and the effect of treatment with fludarabine and rapamycin on HMGB1 mRNA expression was also observed. Results After being stimulated with 75-100ng/ml LPS, the HMGB1 mRNA expressions in macrophages were up-regulated markedly, peaking at 24-36 hours, and remained elevated up to 48 hours. It was found that the HMGB1 mRNA expression was significantly inhibited by treatment with either fludarabine (100μmol/L) or rapamycin (25ng/ml). Conclusions These data suggest that LPS stimulation can result in up-regulation of HMGB1 mRNA expression in peritoneal macrophages in rats. Janus kinase/STAT pathway may be involved in modulating HMGB1 mRNA expression in LPS-activated macrophages.