Lentils (Lens culinaris, L.) Attenuate Colonic Lesions and Neoplasms in Fischer 344 Rats

Objective: Lentils (Lens culinaris, L.) contain several bioactive compounds that have been linked to theprevention of cancer. However, the in vivo chemopreventive ability of lentils against chemically-inducedcolonic lesions has not been previously examined. Our present study examined the hypothesis thatlentils could suppress neoplasmic growth in vivo by virtue of their bioactive micro- and macro-constituents, and that culinary thermal treatment could affect the chemopreventive potential. Methods: To accomplish this goal, raw whole lentils (RWL), raw split lentils (RSL), cooked wholelentils (CWL) and cooked split lentils (CSL) were used. Pluronic F-68 (PF68), which is a well-studiedchemopreventive agent, was used also for the purpose of comparison. Sixty weanling Fisher 344 malerats, 4-5 weeks of age, were randomly assigned to six groups (10 rats/group): the control group (C)received AIN-93G diet; treatment lentil groups of RWL, CWL, RSL and CSL received the treatmentdiets containing AIN-93G+5% of lentils, while PF68 group received C+1% PF68 diet. Afteracclimatization for 1 week, all animals were put on the control and treatment diets separately for 5weeks. At the end of the fifth week of feeding, all rats received two s.c. injections of azoxymethane(AOM) carcinogen at 15 mg/kg rat body weight/dose once a week for two consecutive weeks. After 17weeks of the last AOM injection, all rats were euthanized. Results: Total colonic lesions and neoplasms (mean ±SEM) ranged from 6 to 8 for lentil groups, with areduction value of 43 to 57% from the control (C) group (14 lesions). Incidence of severe dysplasia wasreduced significantly (P=0.0022) in the colons of rats fed on lentils (0%-10%), except RWL (20%)when compared with the control (40%) whilst incidence of adenocarcinomas was reduced significantly(P=0.0430) in lentil groups (0-10%), except RSL (20%), when compared with the control (40%). Conclusion: Our findings indicate that the consumption of lentils may attenuate colon carcinogenesis inanimal models, and that hydrothermal treatment resulted in an improvement in the chemopreventivepotential.