Pan H, Wu J, Zheng S
Cancer Institute, Zhejiang Medical University, Hangzhou.
Zhonghua Yu Fang Yi Xue Za Zhi. 1995 Nov;29(6):356-9.
Colorectal cancer was induced by subcutaneous injection of 1,2-dimethylhydrazine (DMH) in mice, and the animals were administered orally with 0.4% of tea polyphenols (TP) simultaneously for 20 weeks to study its preventive effects. Results showed incidence of colorectal cancer in mice administered with TP was significantly lower than in positive controls (P < 0.05), and average number of tumor foci and proportion of adenocarcinoma were significantly fewer in TP group than in positive controls (P < 0.01). Level of cytochrome P450 (CP450) in liver microsome of the mice administered with TP was lower than that both in negative and positive controls (P < 0.01), and activities of superoxide dismutase (SOD) in liver tissue were higher than those in positive controls (P < 0.01), but lower than in negative controls (P < 0.01). Proliferative index of epithelial cells in mice was not obviously influenced by TP. It suggested that TP could have preventive effects on experimental colorectal cancer with a possible mechanism of lowering CP450 and increasing the activity of SOD in the liver.
通过给小鼠皮下注射1,2 - 二甲基肼（DMH）诱导结直肠癌，并同时给动物口服0.4%的茶多酚（TP），持续20周，以研究其预防效果。结果显示，给予TP的小鼠结直肠癌发病率显著低于阳性对照组（P < 0.05），TP组的肿瘤病灶平均数和腺癌比例显著少于阳性对照组（P < 0.01）。给予TP的小鼠肝脏微粒体中细胞色素P450（CP450）水平低于阴性和阳性对照组（P < 0.01），肝脏组织中超氧化物歧化酶（SOD）活性高于阳性对照组（P < 0.01），但低于阴性对照组（P < 0.01）。TP对小鼠上皮细胞增殖指数无明显影响。这表明TP对实验性结直肠癌可能具有预防作用，其可能机制是降低肝脏中的CP450并增加SOD活性。
