STAT1／SOCS1在高迁移率族蛋白1诱导的大鼠滑膜细胞中的表达

The expression of STATI/SOCS1 on the rat synoviocytes induced by high mobility group box

目的探讨高迁移率族蛋白fHMGB）I对滑膜细胞增殖的影响及机制。方法①常规培养的滑膜细胞，随机分为正常对照组和肿瘤坏死因子（TNF）-α组，培养6、12h和24h，反转录-聚合酶链反应（RT—PCR）和免疫细胞化学法（ICC）检测HMGB1mRNA及蛋白在滑膜细胞中的表达变化；②常规培养的滑膜细胞，随机分为正常对照组、HMGB1组，分别培养6、12h和24h，RT—PCR检测磷酸化信号转导和转录激活因子（p—STATI）mRNA表达；ICC和流式细胞术（FCM）检测p—STAT1、细胞激酶信号抑制剂（SOCSI）蛋白的表达；ICC检测PCNA蛋白的表达。结果①TNF—α刺激6、12、24h显著上调HMGB1mRNA的表达[0．86，0．92，1．06vs0．70，P〈0．01]；其蛋白表达亦增强，HMGB1蛋白不仅表达于细胞核，而且出现于胞质中；②HMGB1作用6、12、24h显著增强STAT1mRNA及蛋白的表达量[0．30，0．69，1．05vs0．24，P〈0．01）]及[1．34±0．09，1．55±0．16，1．74±0．13vs1．00±0．15，P〈0．01]；SOCS1蛋白量分别为1．43±0．10、1．58±0．05和1．24±0．15，呈先升高后下降。③p—STATI与SOCS1蛋白表达呈负相关（r=-0．484，P=0．04）。结论HMGB1是滑膜细胞增殖过程中的重要细胞因子，其可能通过上调STAT1的表达和活性，促进细胞增殖。

Objective To investigate the effect and possible mechanisms of high mobility group box （HMGB） 1 on the proliferation of RSC-364 synoviocytes. Methods （1） RSC-364 cells stimulated by 10 μg/L TNF-α and cells of the normal control groups were collected at 6, 12, 24 h respectively in vitro. HMGBhnRNA and protein was detected by reverse transcription polymerase chain reaction （RT-PCR） and immunocytochemistry （ICC）; （2） RSC-364 cells induced by 10 μg/L HMGB1 were collected in 6, 12, 24 h respectively, so did normal control group cells in vitro. The expression of signal transducer and activator of transcription （STAT） mRNA 1 was detected by RT-PCR. The expression of STATland SOCS1 proteins were detected by ICC and flow cytometry analysis （FCM）. The expression of PCNA was detected by ICC. Results Compared with the control group, TNF-α markedly up-regulated HMGB1 mRNA at 6, 12, 24 h respectively [0.86, 0.92, 1.06 vs 0.70, P〈0.01 ], as well as protein expressfon level. Positive signal of HMGB1 proteins was not only expressed in nuclear but also in cytoplasm after stimulation. （2） Compared with normal group, HMGB1 increased the expression of P-STAT1 mRNA and protein at 6, 12, 24 h respectively [0.30, 0.69, 1.05 vs 0.24, P〈0.01 ] and [ 1.34±0.09, 1.55±0.16, 1.74±0.13 vs 1.00±0.15, P〈0.01]. The expression of SOCS1 protein increased significantly in HMGB1 group at 6 and 12 hours （ 1.43±0.10 vs 1.58±0.05）, but it decreased at 24 hours （1.24±0.15）. （3） The expression of p-STAT1 protein was negatively correlated with that of SOCS1 protein. Conclusion HMGB1 appears to be an important mediator in the proliferation of RSC-364 cells, partly by up-regulating the expression and activity of p-STAT1.