Reddyvari Hymavathi, Govatati Suresh, Matha Sumanth Kumar, Korla Swapna Vahini, Malempati Sravanthi, Pasupuleti Sreenivasa Rao, Bhanoori Manjula, Nallanchakravarthula Varadacharyulu
Department of Biochemistry, Sri Krishnadevaraya University, Anantapur 515 003, India.
Department of Environmental Sciences, Andhra University, Visakhapatnam 530 003, India.
J Adv Res. 2017 May;8(3):289-295. doi: 10.1016/j.jare.2017.02.002. Epub 2017 Feb 24.
The present study principally sought to investigate the effect of green tea extract (GTE) supplementation on hepatic mitochondrial DNA (mtDNA) damage in alcohol receiving rats. MtDNA was isolated from hepatic tissues of albino wistar rats after alcohol treatment with and without GTE supplementation. Entire displacement loop (D-loop) of mtDNA was screened by PCR-Sanger's sequencing method. In addition, mtDNA deletions and antioxidant activity were measured in hepatic tissue of all rats. Results showed increased frequency of D-loop mutations in alcoholic rats (ALC). DNA analysis predicted higher free energy for and alleles compared to their corresponding wild alleles which represents less stable secondary structures with negative impact on overall mtDNA function. Interestingly, D-loop mutations observed in ALC rats were successfully restored on GTE supplementation. MtDNA deletions were observed in ALC rats, but intact native mtDNA was found in ALC + GTE group suggesting alcohol induced oxidative damage of mtDNA and ameliorative effect of GTE. Furthermore, markedly decreased activities of glutathione peroxidise, superoxide dismutase, catalase and glutathione content were identified in ALC rats; however, GTE supplementation significantly ( < 0.05) restored these levels close to normal. In conclusion, green tea could be used as an effective nutraceutical against alcohol induced mitochondrial DNA damage.
本研究主要旨在探究补充绿茶提取物（GTE）对接受酒精的大鼠肝脏线粒体DNA（mtDNA）损伤的影响。在用和不用GTE补充剂对白化Wistar大鼠进行酒精处理后，从其肝脏组织中分离出线粒体DNA。通过PCR-Sanger测序法筛选线粒体DNA的整个置换环（D环）。此外，还测定了所有大鼠肝脏组织中的线粒体DNA缺失和抗氧化活性。结果显示，酒精性大鼠（ALC）中D环突变的频率增加。DNA分析预测，与相应的野生等位基因相比，和等位基因具有更高的自由能，这代表着二级结构稳定性较低，对线粒体DNA的整体功能有负面影响。有趣的是，在补充GTE后，ALC大鼠中观察到的D环突变成功恢复。在ALC大鼠中观察到线粒体DNA缺失，但在ALC + GTE组中发现完整的天然线粒体DNA，这表明酒精会诱导线粒体DNA的氧化损伤以及GTE的改善作用。此外，在ALC大鼠中发现谷胱甘肽过氧化物酶、超氧化物歧化酶、过氧化氢酶的活性和谷胱甘肽含量显著降低；然而，补充GTE可显著（<0.05）将这些水平恢复至接近正常。总之，绿茶可作为一种有效的营养保健品，对抗酒精诱导的线粒体DNA损伤。
