目的探讨凋亡相关蛋白Bcl-2/Bax、Caspase-3的表达和抗氧化能力与少突胶质细胞(0L)对氧化损伤的成熟依赖性关系。方法用不同浓度过氧化氢(H2O2)刺激培养OL前体及成熟0L,应用MTT法检测细胞活力。应用Western blot分别检测两种细胞Bcl-2/Bax和Caspase-3的蛋白表达,并用比色法检测细胞总超氧化物歧化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性以及丙二醛(MDA)的含量。结果在不同H2O2浓度的刺激下,OL前体的细胞活力均明显低于成熟OL。OL前体的Bax和Caspase-3蛋白表达明显高于成熟OL,Bcl-2蛋白表达则明显低于成熟OL:其T-SOD、GSH-Px和CAT的活性亦明显弱于成熟OL,但MDA含量明显升高,差异有统计学意义(P〈O.05)。结论OL对氧化损伤的成熟依赖性与其Bcl-2/Bax、Caspase-3在不同阶段中的表达差异以及抗氧化能力不同有关。
Objective To explore the maturation-dependent vulnerability of oligodendrocytes (OLs) to oxidative injury and its relationship with the expressions of apoptosis-related proteins (Bcl-2/Bax, Caspase-3), and antioxidative abilities. Methods Cultured OL progenitors and mature OLs were exposed to H2O2 of different concentrations, and their cell viability was detected with MTT assay. Western blot was used to detect the expressions ofBcl-2, Bax and Caspase-3 proteins in both of OL progenitors and mature OLs. Activities of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) and level of malondialdehyde (MDA) were detected by chromatometry. Rusults H2O2 caused a concentration-dependent decrease in cell viability, and the viabilities of OL progenitors were significant lower than that of mature OLs. There were the higher expressions of either Bax or Caspase-3 and lower expression of Bcl-2 in OL progenitors compared to those in mature OLs. Activities of T-SOD, GSH-Px and CAT were lower while MDA was higher in OL progenitors than those in mature cells. Conclusions Differences in either the expressions of Bcl-2, Bax and Caspase-3 or the antioxidative ability in different developmental stages of OLs are correlated with the maturation-dependent vulnerability of OLs to oxidative injury.