活化星形胶质细胞中线粒体生物发生增强

Mitochondrial biogenesis is increased in activated astrocytes

目的 观察星形胶质细胞（AS）活化后其线粒体生物发生的变化情况。方法 分离新生大鼠大脑皮质AS并纯化培养，随机分为正常对照组、脂多糖（LPS）＋干扰素-γ（IFN-γ）联合刺激6h组、12h组和24h组，酶联免疫吸附法检测AS分泌肿瘤坏死因子（TNF-α）和白细胞介素-6（IL-6）浓度，蛋白质印迹法检测过氧化物酶体增殖物激活受体γ辅助激活因子-1α（PGC-1α）、线粒体细胞色素C氧化酶亚单位1fCOX1）、线粒体细胞色素C氧化酶亚单位2（COX2）、视神经萎缩1基因蛋白（OPA1）和动力相关蛋白1（DRP1）蛋白的表达情况，实时定量聚合酶链反应（RT-PCR）检测AS线粒体DNA相对含量，透射电镜观察计算AS线粒体体积密度。结果 6h组、12h组和24h组TNF-α和IL-6浓度均较正常对照组显著升高，差异具有统计学意义（P〈0．05）；6h组和12h组PGC-1α、COX1、COX2、OPA1和DRP1蛋白浓度均较正常对照组显著增加，差异具有统计学意义（P〈0．05）；12h组和24h组AS线粒体DNA相对含量较正常对照组显著增加，差异具有统计学意义（P〈0．05）；24h组AS线粒体体积密度较正常对照组显著增加，差异具有统计学意义（P〈0．05）。结论 线粒体生物发生在活化AS中增强。

Objective To investigate the changes of mitochondrial biogenesis in activated astrocytes （ASS）. Methods The ASs isolated from neonatal rat cerebral cortex were purified and cultured; and then, they were randomly divided into 4 groups： control group, and lipopolysaccharide （LPS） and interferon-γ （IFN-γ） insulted 6, 12 and 24 h groups. The levels of tumor necrosis factor-ct （TNF-ct） and interleukin-6 （IL-6） were detected by enzyme-linked immuno sorbent assay. The expressions of peroxisomal proliferator-activated receptor gamma coactivator 1 alpha （PGC-1α）, cytochrome C oxidase 1 （COX1）, COX2, optic atrophy 1 gene protein （OPAl） and dynamin-related protein 1 （DRP1） were detected by Western blotting. The mitochondrial DNA relative content was detected by real-time polymerase chain reaction （RT-PCR）. The mitochondrial volume density was observed by transmission electron microscopy. Results The levels of TNF-α and IL-6 in the LPS and IFN-γ/insulted 6, 12 and 24 h groups were significantly increased as compared with those in the control group （P〈0.05）. The protein expressions of PGC-1α, COX1, COX2, OPAl and DRP1 in LPS and IFN-γ insulted 6 and 12 h groups were significantly increased as compared with those in the control group （P〈0.05）. The mitochondrial DNA relative contents in LPS and IFN-γ insulted 12 and 24 h groups were significantly increased as compared with those in control group （P〈0.05）. The mitochondrial volume density was dramatically increased in LPS and IFN-γ, insulted 24 h group as compared with that in the control group （P〈0.05） Conclusion Mitochondrial biogenesis is increased in ASs.