Evaluation of co-stimulatory effects of Tamarindus indica L. on MNU-induced colonic cell proliferation.

Colonic cell proliferation is the prerequisite for the genesis of cancer. Experimental and epidemiologic evidence indicate dietary factors to be one of the commonest predisposing factors in the development of several types of cancers including large intestine. Here we have investigated the role of the fruit pulp of Tamarindus indica L. (TI), a tropical plant-derived food material, on the proliferating colonic mucosa using Swiss albino mice. Crypt cell proliferation rate (CCPR), on histological basis and [3H]-thymidine incorporation assay were chosen to evaluate the modulating potential of TI per se and in response to a subacute dose of N-nitroso N'-methyl urea (MNU). Descending colonic segment showed greater rate of cell proliferation than the ascending colon and cecum tissues isolated from the group 2 (TI-per se) when compared with group 1 (negative controls). It also revealed a positive correlation with the incorporation studies. Significant increase in the CCPR and radiolabeled precursor incorporation (p <0.001) was observed in MNU-induced+TI fed group of animals (group 4) in all the three segments when compared with control diet fed normal (group 1) as well as MNU-induced (group 3) animals. This study therefore indicates a co-stimulatory effect of TI on MNU-induced colonic cell kinetics.