甲基紫精对丹参培养细胞抗氧化防护系统的影响

Effects of methyl viologen on the antioxidant system in cultured Salvia miltiorrhiza cells

为了探讨甲基紫精(MV)对丹参(Salvia miltiorrhiza)体内抗氧化防护系统的影响及其生理机制。以MV为诱导剂,以敌草隆(DCMU)为抑制剂,考察了MV与DCMU处理后丹参悬浮培养细胞中H2O2、丙二醛、还原型谷胱甘肽的含量以及抗氧化防护酶(超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT))活性变化和同工酶的表达差异。结果表明,MV处理显著提高了丹参培养细胞内H2O2、丙二醛以及还原型谷胱甘肽含量;MV处理使CAT、POD活性增强,谱带颜色更亮,条带增加。DCMU处理显著抑制了MV诱导的H2O2、丙二醛、还原型谷胱甘肽含量的增加,抗氧化酶活性的升高和同工酶的表达。以上结果说明,MV可诱导丹参培养细胞叶绿体产生H2O2,H2O2激活了丹参培养细胞抗氧化防护系统以维持细胞正常的生理活动。

Aims We studied the effects of the methyl viologen （MV） in the culture medium on the antioxidant enzyme sys-tem in Salvia miltiorrhiza cells and investigated changes in the contents of H_2O_2, malonaldehyde （MDA）, glu-tathione （GSH）, and antioxidant enzyme. The differential expressions of superoxide dismutase （SOD）, peroxidase （POD）, and catalase （CAT） were discussed. Our objective was to explore if the MV could significantly affect the antioxidant system in the cultured S. miltiorrhiza cells. Methods We treated the S. miltiorrhiza cells in suspension cultures with MV as an elicitor on the accumulation of H_2O_2, and used the diuron （DCMU） as an electron transporting antagonist. The biosynthesis of H_2O_2, MDA, and GSH, and the activities of SOD, CAT, and POD were determined by ultraviolet spectrophotometry. The spe-cific isoenzymes bands of SOD, CAT, and POD were examined by acrylamide gel electrophoresis technique. Important findings We found that MV significantly increased the accumulation of H_2O_2, MDA, and GSH, along with increased activities of CAT and POD as well as enhanced expressions and increased number of isoenzymes bands of CAT and POD;whereas DCMU inhibited the effects of MV. Results in this study suggest that MV could significantly enhance H_2O_2 accumulation in chloroplasts and regulate the antioxidant system in S. miltiorrhiza cells in suspension cultures, in order to maintain normal physiological conditions.