Indian Journal of Experimental Biology Vol. 42, June 2004, pp. 595-600 Effect of amaranth leaves on dimethylhydrazine-induced changes in multicomponent antioxidant system of rat liver K R Anilakumar*, Farhath Khanum, K R Sudarshanakri s hn a & K Santhanam Biochemistry and Nutrition Discipline, Defen ce Food Res ea rch Laboratory, Mysore 570 011. India Received 22 Ma y 2003; revised 17 February 2004 Effect of prefee ding dehydrat ed amaranth (A. gallgeliclI s) leaves at 10 and 20% levels on a chemical toxi ca nt, dimethylhydrazine (DMH)-induced free radical stress in rat liv er was evaluated. DMH -induced ri se in hepa ti c malondialdehyde ( MDA) , was diminished by AL. AL intake resulted in a significant increase in hepatic glutathione (GSH). Th e feeding of AL at 10%level increased the hepatic glucose-6- phosphate de hydroge nase (G-6-PDH) activity, while that at 20 % level increa sed the hepa tic glutathione reductase (GSSGR) as well, in addition to G-6-PDH. Amaranth l eaves at 10 and 20% levels of feeding diminished the hepatic superoxide dismutase and glutat hi one peroxidase (GSH-Px) activities. DMH influenced adversely the hepatic antioxidant enzyme activities. Simu lt aneous administration of DMH and feeding of AL enhanced the DMH-induced d ec rease in hepatic GSH-Px. DMH enhan ced formation of micronuclei was reve rt ed significantly by AL intake. Hen ce , it was concluded that the consumption of AL at 20% level reduced DMH-induced impaired antioxidant status in rat li ver. Keywords : Amaranth leaf, Antioxidant, Liver, Multicomponent antioxidant system, Rat IPC Code: Int CI 7 A61 K Amaranth leaves (Amaranthus gangeticus Linn.) are widely consumed as a vegetable in India and are rich in carotenoids. The carotenoids and perhaps non- nutrients like dietary fibre and other phenolic constituents influence the enzymes involved in the activation and detoxification of xenobiotics including carcinogens. This effect cou ld primarily be mediated through alterations in levels of phase I cytochrome P-4S0 enzyme -d ependent metabolism of carcinogens and induction of phase-II enzymes i.e. glutathione S- transferase, glutathione reductase, glutathione peroxidase, catalase etc. I - 4 . Therefore, vegetables are important source of antioxidant nutrient and non- nutrients and are being advocated for use in the dietary management of degenerative diseases. The antioxidant compounds have been well recognized to have effective role in reducing the oxidation stress and thereby, reduce the risk of cancer. National Research Counci I, therefore, has recommended an increased consumption of fruits and vegetables 5 . There are several reports on cabbage 6 , garlic 7 , carrot S, I 9 B I 10 h . . I curry eaves russe s sprouts etc. on t elr potentia beneficial effects per se as well as against chemically induced carcinogenesis. Fibre ll , calcium l2 and folic *Corrcspondent author: Tel : +91-821-473290. Fax:+9 1- 82 1-474282. E-mail: dfoodlab @sancharnet.in acid 13 are some of the food components, currently in the centre of research to ascertain their effects. Amaranth leaves contain dietary fibre, folic acid 14 and perhaps other bioactive nutrients such as bioflavonoids. Flavonoids are also reported to possess antioxidant potency 15. Further , amaranth leaves contain Mg , an antimutagen and chlorophyllin, a proven efficient anti mutagen and antioxidant l6 . The knowledge presently available on the potential for protective capacity of dietary components like green leafy vegetables in many instances is sparse and insufficient to make dietary advice on food selection. This study was, therefore, undertaken to investigate whether the cons umpti on of dehydrated leaves of amaranth have any beneficial effect in preventing or protecting against the toxicity of a cancer causing xenobiotic, dimethylhydrazine (DMH), which is known to induce oxidati ve stress 17 . Materials and Methods Preparation of dehydrated amaranth leaves diet--Good quality fresh amaranth (Amarallthus gallgeticus) leaves procured from local market were wa shed, blanched for 2 min with 0.12% potassium metabisulphite and dried in a cross flow drier till the moisture content was reduced to 9%. The dehydr ated amaranth leaves (AL) thus prepared were powdered