Department of Zoology, Panjab University, Chandigarh 160014, India.
Food Chem Toxicol. 2012 Dec;50(12):4375-81. doi: 10.1016/j.fct.2012.08.045. Epub 2012 Aug 30.
In the current investigation the ameliorative effect of 2% extract of green tea (GT) and white tea (WT) against benzo(a)pyrene (BaP) induced toxicity and DNA damage has been studied in liver and lung of Balb/c mice (8 animals per group). The activities of phase I enzymes such as 7-ethoxyresorufin O-deethylase (EROD) and pentoxyresorufin O-depentylase (PROD) were found to be increased (p<0.05) both in liver and lung of BaP treated (125 mg/kg b.w. orally) group. The enhanced activities of EROD and PROD were inhibited in group that received pretreatment with GT and WT for 35 days. Pretreatment with GT and WT also elevated (p<0.05) the level of detoxifying enzymes such as glutathione S-transferase (GST) and quinone reductase (QR) in both the tissues. The BaPDE-DNA adducts level reflected the decreasing pattern from BaP treated group to the groups that received pretreatment with GT and WT. BaP exposure induced drastic alterations in the morphology of erythrocytes, pretreatment of GT and WT to BaP administered groups showed reduced alteration in topography of erythrocytes. WT elucidate greater efficacy in ameliorating BaP toxicity, but further long term studies are required to validate white tea as a cancer chemopreventive agent.
在目前的研究中，研究了 2%绿茶（GT）和白茶（WT）提取物对苯并（a）芘（BaP）诱导的毒性和 DNA 损伤的改善作用，实验对象为 Balb/c 小鼠的肝脏和肺部（每组 8 只动物）。结果发现，BaP 处理组（125mg/kg bw 口服）的肝脏和肺部中，I 相酶如 7-乙氧基resorufin O-脱乙基酶（EROD）和戊氧基resorufin O-脱戊基酶（PROD）的活性均升高（p<0.05）。用 GT 和 WT 预处理 35 天的组，可抑制 EROD 和 PROD 活性的增强。GT 和 WT 的预处理还可提高两种组织中解毒酶如谷胱甘肽 S-转移酶（GST）和醌还原酶（QR）的水平（p<0.05）。BaPDE-DNA 加合物水平反映了从 BaP 处理组到 GT 和 WT 预处理组的降低模式。BaP 暴露引起红细胞形态的剧烈变化，GT 和 WT 预处理 BaP 给药组可减少红细胞形态的变化。WT 阐明了对 BaP 毒性的更大疗效，但需要进一步的长期研究来验证白茶作为癌症化学预防剂的功效。
