DOXORUBICIN INDUCED NEURO- AND CARDIOTOXICITIES IN EXPERIMENTAL RATS: PROTECTION AGAINST OXIDATIVE DAMAGE BY THEOBROMA CACAO STEM BARK

Kosoko A. M.*, Olurinde O. J. and Akinloye O. A.

ABSTRACT

80 rats, randomly selected, were divided into 3 treatment groups: pre-, co- and post-treatment; consisting of 6 sub-groups each (5 rats per sub-group): baseline, normal saline (2 mL), α-lipoic acid (20 mg/kg body weight), 200 mg/kg, 400 mg/kg or 800 mg/kg body weight Theobroma cacao stem bark aqueous extract (TCAE). All rats except for baseline group were intoxicated with 20mg/kg body weight doxorubicin (DOX) intraperitoneally. The animals in pre- or post-treatment group received a single dose of DOX (20 mg/kg body weight) intraperitoneally 24h before or after 7 days’ oral administration with TCAE respectively while those in co-treatment group were co-administered 2.86 mg/kg body weight of DOX with either normal saline, α- lipoic acid or TCAE orally for 7 days. Animals were sacrificed (pre- and post- treatment groups were sacrificed on the ninth day while the co-treatment group sacrificed on the 8th day). Brain and heart tissue samples were harvested for enzyme markers of toxicity, oxidative stress and histopathological examinations. DOX intoxication caused significant decrease in activities of LDH and ACP, and increase in γGT and ALP activities in brain tissues while causing a significant increase in LDH, ACP, γGT activities and decrease in ALP activity in the cardiac tissues. DOX intoxication caused a significant increase in concentrations of H2O2 generated, MDA and PC, XO, MPx and NOX activities with concomitant decrease in CAT, SOD, GPx and GST activities, and in concentrations of GSH, AsA and α-Toc in brain and cardiac tissues. Pre-, co- and post-treatment with TCAE at either 200 mg/kg, 400 mg/kg or 800 mg/kg body weight significantly reversed the oxidative damage to the organs induced by DOX-intoxication. The result affirmed that T. cacao stem bark aqueous extract protected against DOX induced oxidative damage in brain and cardiac tissues of experimental rats.

Keywords: Chemoprevention; Theobroma cacao; Doxorubicin; Oxidative stress; Neurotoxicity; Cardiotoxicity.