维生素C增强氧化砷联用二甲萘醌诱导的U937细胞凋亡及其机制

目的 探讨维生素C是否可增强三氧化二砷（As2O3）联用二甲萘醌（DMNQ）对白血病细胞株U937的促凋亡效应及其机制。方法 以As2O3、维生素C、DMNQ不同组合孵育细胞，采用流式细胞仪及电镜检测细胞凋亡，并设立各种对照。结果 维生素C可增加As2O3联用DMNQ（10μmol/L）诱导U937细胞发生凋亡的比例（不加和加用维生素C细胞凋亡率分别为35.24%和61.20%）；过氧化氢酶可逆转这一效应；维生素C对DMNQ（20μmol/L）单独诱导U937细胞凋亡无影响。结论 维生素C在As2O3存在的情况下，通过活性氧依赖的途径，促进U937细胞凋亡。

Ascorbic acid enhances the apoptosis of U937 cells induced by arsenic trioxide in combination with DMNQ and its mechanism

OBJECTIVE: To investigate whether ascorbic acid could enhance the efficacy of arsenic trioxide (As(2)O(3)) combined with 2, 3-dimethoxy-1, 4-naphthoquinone (DMNQ) in inducing the apoptosis of leukemia cell line U937 and its possible mechanism. METHODS: Flow cytometry and electron microscopy were applied to detect apoptosis of U937 cells after treatment with various combinations of As(2)O(3), DMNQ and ascorbic acid for 24 hours. RESULTS: As(2)O(3) and DMNQ induced-apoptosis of U937 cells was enhanced (35.24%-->61.20%) upon cotreatment with ascorbic acid. Catalase could reverse this effect of DMNQ. Ascorbic acid had no effect on DMNQ-induced apoptosis of U937 cells. CONCLUSION: Ascorbic acid enhanced the apoptosis of U937 cells via reactive oxygen species-dependent pathway in the presence of As(2)O(3).