Bhuvaneswari V, Velmurugan B, Balasenthil S, Ramachandran C R, Nagini S
Department of Biochemistry, Faculty of Science, Annamalai University, Annamalainagar-608 002, Tamil Nadu, India.
Fitoterapia. 2001 Dec;72(8):865-74. doi: 10.1016/s0367-326x(01)00321-5.
The chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was examined using lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR) as biomarkers of chemoprevention. Twenty four male Syrian hamsters were divided into four groups of six animals each. The right buccal pouches of the animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in group 2 were painted with DMBA as in group 1 and in addition received 2.5 mg/kg body weight lycopene orally three times a week on days alternate to DMBA application. Group 3 animals received lycopene as in group 2. Animals in group 4 received neither DMBA nor lycopene and served as control. The hamsters were killed after an experimental period of 14 weeks. Biochemical measurements were carried out in tumour and normal tissues. All hamsters painted with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH, GPx, GST and GR. Administration of lycopene significantly suppressed DMBA-induced oral carcinogenesis as revealed by the absence of carcinomas. The results of the present study suggest that lycopene may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the activities of the enzymes in the glutathione redox cycle.
以脂质过氧化、还原型谷胱甘肽（GSH）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽S-转移酶（GST）和谷胱甘肽还原酶（GR）作为化学预防的生物标志物，研究了番茄红素对7,12-二甲基苯并[a]蒽（DMBA）诱导的仓鼠颊囊（HBP）癌变的化学预防效果。将24只雄性叙利亚仓鼠分为四组，每组6只。第1组动物的右侧颊囊每周用0.5% DMBA的液体石蜡溶液涂抹三次。第2组动物按第1组方法涂抹DMBA，此外，在与涂抹DMBA的日子交替的日子里，每周口服三次2.5 mg/kg体重的番茄红素。第3组动物按第2组方法接受番茄红素。第4组动物既不接受DMBA也不接受番茄红素，作为对照。实验14周后处死仓鼠。在肿瘤组织和正常组织中进行生化测定。所有仅用DMBA涂抹14周的仓鼠均发生了高分化鳞状细胞癌。口腔肿瘤组织中脂质过氧化减少，同时GSH、GPx、GST和GR水平显著升高。番茄红素的给药显著抑制了DMBA诱导的口腔癌变，表现为无癌发生。本研究结果表明，番茄红素可能通过调节脂质过氧化和增强谷胱甘肽氧化还原循环中酶的活性来发挥其化学预防作用。
