Effects of a bioactive amine on 1,2-dimethylhydrazine treated rats fed polyunsaturated fat diet

Neomycin, a biogenic amine, well known for its manifold biological activities, is a potent hypocholesterolemic agent having significant influence on the sterol metabolism in gut, thereby effective in reducing the risk of coronary heart diseases in which dietary lipids play an important role. A high cholesterol diet increases the risk of atherosclerosis whereas a diet rich in polyunsaturated fatty acids reduces the risk owing to the serum cholesterol lowering property of the latter. However, a low serum cholesterol level poses a considerable danger of development of colon cancer. Epidemiological and animal model studies have demonstrated that the availability of cholesterol in gut and its subsequent conversion into promoters or cc-carcinogens by the intestinal microflora are the focal points of colon carcinogenesis. Present study reports the effects of neomycin on the incidence of large bowel tumorigenesis and excretion pattern of fecal sterols in rats with colon tumours induced by 1,2-dimethylhydrazine, fed polyunsaturated fat diet. Neomycin feeding has significantly enhanced colon tumour development in the experimental animals. Fecal excretion of sterols did not show any significant variation except coprostanol, the concentration of wh ich has been increased and cholesterol, cholic and deoxycholic acids which showed inverse relationships with neomycin feeding.