创伤性脑损伤后IL-1β在神经胶质细胞中经时定位表达的研究

Research of the Time Orientation Expression of IL-1β in Glial Cells after Traumatic Brain Injury

目的:探讨创伤性脑损伤(TBI)后白细胞介素-1β(IL-1β)在神经胶质细胞中的经时定位表达情况。方法:选择72只SPF级雄性小鼠分为假手术组(sham组)、TBI 6h组、TBI 12h组、TBI 1d组、TBI 4d组与TBI 7d组,每组12只,分别在脑损伤后6h、12h、1d、4d、7d时获取血清和脑组织并且制作切片。ELISA检测损伤后炎症因子IL-1β、白细胞介素-6 (IL-6)和肿瘤坏死因子-α(TNF-α)的表达。Western blot检测钙离子结合蛋白-1(IBA-1)和胶质纤维酸性蛋白(GFAP)的表达。应用免疫荧光双重染色技术观察炎症因子IL-1β在小胶质细胞和星形胶质细胞中的定位表达情况。结果:TBI后6h-7d时炎症因子IL-1β、IL-6和TNF-α的表达量均高于sham组(P<0.05)。Western blot结果显示,IBA-1的表达在损伤后6h-7d时高于sham组,GFAP的表达在损伤后1d-7d时高于sham组(P<0.05)。免疫荧光双重染色技术显示,6h、12h时IL-1β主要表达在小胶质细胞中,IL-1β和IBA-1共表达细胞数量多于sham组(P<0.05);1d、4d、7d时IL-1β主要表达在星形胶质细胞中,IL-1β和GFAP共表达细胞数量多于sham组(P<0.05)。结论:TBI诱导了胶质细胞和炎症因子的表达,其表达随脑损伤的时间而变化,IL-1β早期定位表达于小胶质细胞,后期定位表达于星形胶质细胞中。

Objective: To investigate the time orientation expression of interleukin-1β(IL-1β) in glial cells after traumatic brain injury(TBI). Methods: 72 cases of SPF male mice were selected and divided into sham operation group(group sham), group TBI 6 h,group TBI 12 h, group TBI 1 d, group TBI 4 d, group TBI 7 d, 12 cases in each group. Serum and brain tissues were obtained after brain injury at 6 h, 12 h, 1 d, 4 d and 7 d. The expression of IL-1β, interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by ELISA.The expression of ionized calcium binding adaptor molecule-1(IBA-1) and glial fibrillary acidic protein(GFAP) were detected by Western blot. The expression of IL-1β in microglia and astrocytes was observed by immunofluorescence double staining. Results: The expression inflammatory factors IL-1β, IL-6, TNF-α were higher than sham group at 6 h-7 d after TBI(P <0.05). Western blot results showed that the expression of IBA-1 were higher than sham group at 6 h-7 d after injury, the expression of GFAP were higher than sham group at 1 d-7 d after injury(P<0.05). Immunofluorescence double staining showed that IL-1β was mainly expressed in microglia at 6 h and 12 h, the number of IL-1β and IBA-1 coexpressed were more than that in sham group(P <0.05). IL-1β was mainly expressed in astrocytes at 1 d, 4 d and 7 d, the number of IL-1β and GFAP coexpressed were more than that in sham group(P<0.05). Conclusion: TBI induced the expression of glial cells and inflammatory factors, and the expression changes with the time of brain damage. IL-1β is expressed in the microglia at an early stage and it is expressed in astrocytes at the later stage.