Detaruim microcarpum Guill. & Perr is a leguminous African plant with significant nutritional and medicinal uses. In an experimental N-methyl nitroso urea (MNU) induced colon carcinogenesis in rats, various concentrations of pulverized D. microcarpum fruits were included in diets of rats and the chemopreventive effects of these supplemented diets were investigated. The rats were divided into 10 groups (n=7) and fed for 10 weeks with diets containing 2.5%, 5.0% and 10.0% D. microcarpum. Subsequently, the feeding continues for another 12 weeks but with concomitant intra-rectal administration of MNU at every 72 hour interval. Respective control groups fed similar concentrations of supplemented diets, normal diet with or without MNU intoxication were also included. All rats were sacrificed at the end of the 22 weeks experiment; blood collected for hematological analysis and serum was separated for carcinoembryogenic antigen (CEA) assay and other biochemical tests. Liver, kidney and colon were also collected for antioxidant and tissue peroxidation assays. Sections of the colon were subjected to histopathological studies and immunohistochemical (IHC) staining using mutL homolog 1 (MLH1) antibody. A significant (p<0.05) elevation was observed in levels of CEA (210 ± 18 pg/ml) in the MNU positive control group when compared with the test groups and the negative control group (70 ± 6 to 140 ±11 pg/ml). There were significant decreases (p<0.05) in the major hematological parameters (PCV, hemoglobin, WBC etc) levels, catalase and superoxide dismutase (SOD) activities in the MNU control group when compared to other groups. A concomitant significant increases (p<0.05) was also observed in the levels of liver function enzymes and kidney function biomarkers as well as thiobarbituric reactive substance (maliondealdehyde) in the MNU control group when compared to the test groups and other controls . It was further observed that these variations in the CEA and antioxidant status markers were dose dependent in many instances. Histopathological and IHC staining of the colons in the treated groups showed mild changes in tissues with no expression of the MLH1 antibody when compared with the MNU control group having moderate damage and expression of the antibody. Hence it was concluded that the inclusion of fruits of D. microcarpum in the diet protected the organs and tissues of the rats from induced MNU toxicity; ameliorated oxidative stress in colon carcinogenesis model and possibly prevented the initiation of the process of carcinogenesis implying that the fruits possess significant health benefits which may have warranted their usage in foods and also in traditional medicine in Africa.
Citation Format: Mubarak L. Liman, Sunday E. Atawodi. Preventive potentials of the fruits of Detarium microcarpum on N-methyl nitrosourea (MNU) induced colon carcinogenesis in rats [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1269. doi:10.1158/1538-7445.AM2017-1269