山稔子提取物对体外DNA氧化性损伤的保护作用

Protective Effect of Fructus Rhodomyrti on H_2O_2-induced DNA Damage in Vitro

目的观察山稔子提取物对原代体外培养淋巴细胞DNA氧化损伤的保护作用。方法原代培养24h的脾淋巴细胞悬液,随机分为7组,其中5组细胞用不同浓度的山稔子提取物溶液预先处理60min,再加入50μmol/L的H2O2,H2O2染毒组直接加入相同浓度的H2O2,空白对照组加入等量的PBS溶液,7组细胞共同在4℃下染毒20min,收获细胞同时进行单细胞凝胶电泳,计算DNA迁移的细胞率和总彗星长度。结果H2O2可致原代培养脾淋巴细胞的DNA严重损伤,而山稔子提取物能不同程度地降低H2O2诱导产生的DNA损伤,在10、50、100μg/mL的浓度下,彗星细胞出现率从阳性对照组的100%分别降低为85%、65%和30%(P分别<0.05、0.01、0.01),总彗星长度也从对照组的(52.82±6.42)μm,逐渐降低为(43.68±5.59)μm、(35.80±8.75)μm、(25.35±4.32)μm(P分别<0.05、0.01、0.01)。结论山稔子提取物具有抗氧化作用,能在一定浓度范围内保护细胞显著降低氧自由基对DNA的氧化损伤。

Objective To evaluate the protective effect of fIuctus rhodomyrti （FR） on H2O2-induced DNA damage of primarily cultured spleen lymphocytes. Methods Spleen lymphocytes were cultured for 24 h and then divided into 7 groups randomly. 5 groups were treated with different concentrations of FR extracts for 60 min, then with 50 μmol/L H2O2; 1 group was treated with 50 μmol/L H2O2 only and the last group with PBS. Twenty min after H2O2 or PBS treatment, samples were collected for SCGE and the comet length and percentage of cells with migrated DNA were measured. Results H2O2 caused severe DNA damage in primary cultured spleen lymphoeytes and FR extracts reduced the DNA damage from 100% to 85%, 65% and 30% at a concentration of 10, 50 and 100 μg/mL, respectively （P〈0.05, 0.01, 0.01）, and the comet length was reduced from （52.82±6.42）μm to （43.68±5.59）μm, （35.80±8.75）μm and （25.35±4.32）μm （P〈0.05,0.01,0.01）,respeetively. Conclusion FR extract is a strong antioxidant and can protect cells from the damage of ROS-induced DNA injury.