Dhiman M, Mendiz E, Rao A R, Kale R K
Radiation and Cancer Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
Hum Exp Toxicol. 2005 Jun;24(6):303-12. doi: 10.1191/0960327105ht526oa.
As there is a strong correlation between diet and cancer, the dietary constituents that inhibit mutagenesis and/or carcinogenesis are of paramount importance for the prevention of human cancer. In the present study, cancer chemopreventive potentials of different doses of mustard (Brassica compestris) seed mixed diets were evaluated against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis and 3-methylcholantrene (MCA)-induced uterine cervix tumorigenesis. Results showed a significant inhibition of stomach tumour burden (tumours/ mouse) by mustard seeds. Tumour burden was 7.08 +/- 2.47 in the B(a)P-treated control group, whereas it was reduced to 1.36 +/- 1.12 (P<0.001) by the 2.5% dose and 1.18 +/- 0.87 (P<0.001) by the 5% dose of mustard seeds. The cervical carcinoma incidence, as compared to MCA-treated control group (73.33%), was reduced to nil (P<0.05) by the 5% diet of mustard seeds and to 13.33% (P<0.05) by the 7.5% diet of mustard seeds. The effect of the 2.5% and 5% mustard seed mixed diets was also examined on the antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH) and lipid peroxidation in the liver of Swiss albino mice. The glutathione-S-transferase-specific activity was increased (P<0.05) by the 2.5% dose, whereas there was no significant change in the activity of DT-diaphorase. In antioxidant systems, significant elevation of the specific activities of superoxide dismutase and catalase was observed with both doses of mustard seeds (P<0.05). The level of reduced glutathione (GSH) measured as nonprotein sulphydryl content was elevated by the 2.5% dose of mustard seeds only (P<0.05). Lipid peroxidation measured as formation of thiobarbituric acid reactive substances production showed significant inhibition (P<0.05) by the 5% dose of mustard seed mixed diet. LDH activity was decreased significantly (P<0.05) by both the doses. The results strongly suggest the cancer chemopreventive potentials of mustard seeds and their ability to enhance the antioxidant defence system and in turn provide protection against the toxic effects of carcinogens. It is likely that the use of mustard seeds in the diet may contribute to reducing the risk of cancer incidence and burden in the human population.
由于饮食与癌症之间存在密切关联，因此抑制诱变和/或致癌作用的饮食成分对于预防人类癌症至关重要。在本研究中，评估了不同剂量的芥菜（Brassica compestris）籽混合饮食对苯并(a)芘[B(a)P]诱导的前胃肿瘤发生和3-甲基胆蒽（MCA）诱导的子宫颈肿瘤发生的癌症化学预防潜力。结果显示，芥菜籽对胃肿瘤负担（肿瘤数/小鼠）有显著抑制作用。在B(a)P处理的对照组中，肿瘤负担为7.08±2.47，而2.5%剂量的芥菜籽使其降至1.36±1.12（P<0.001），5%剂量的芥菜籽使其降至1.18±0.87（P<0.001）。与MCA处理的对照组（73.33%）相比，5%的芥菜籽饮食使子宫颈癌发病率降至零（P<0.05），7.5%的芥菜籽饮食使其降至13.33%（P<0.05）。还研究了2.5%和5%的芥菜籽混合饮食对瑞士白化小鼠肝脏中抗氧化酶、谷胱甘肽含量、乳酸脱氢酶（LDH）和脂质过氧化的影响。2.5%剂量的芥菜籽使谷胱甘肽-S-转移酶的比活性增加（P<0.05），而DT-黄递酶的活性没有显著变化。在抗氧化系统中，两种剂量的芥菜籽均使超氧化物歧化酶和过氧化氢酶的比活性显著升高（P<0.05）。仅2.5%剂量的芥菜籽使以非蛋白巯基含量衡量的还原型谷胱甘肽（GSH）水平升高（P<0.05）。以硫代巴比妥酸反应性物质生成量衡量的脂质过氧化在5%剂量的芥菜籽混合饮食作用下受到显著抑制（P<0.05）。两种剂量均使LDH活性显著降低（P<0.05）。结果强烈表明芥菜籽具有癌症化学预防潜力，以及增强抗氧化防御系统的能力，进而提供针对致癌物毒性作用的保护。饮食中使用芥菜籽可能有助于降低人群中癌症发病率和负担的风险。
