Journal of Natural Sciences Research www.iiste.org ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online) Vol.6, No.4, 2016 91 Anti-Diabetic Activities of the Leaf and Bark Extracts of Jatropha Curcas on Alloxan-Induced Diabetic Albino Rats V.O. AINA 1 M.B. IBRAHIM 2 M.S. ABDULSALAMI 3 G.O. ADEJO 4 SOLOMON MUSA 1 1. Department of Biochemistry, Faculty of Science,Kaduna State University,Kaduna – Nigeria 2. Department of Applied Science, Kaduna Polytechnic, P.M.B. 2021,Kaduna 3. Department of Biological Sciences, Nigerian Defense Academy, P.M.B 2109,Kaduna 4. Department of Biochemistry and Molecular Biology, Federal University, P.M.B. 5001 – Dutsin-Ma,Katsina – Katsina State Abstract Antidiabetic activity was measured using a glucometer to check blood glucose level before induction with alloxan, after induction with alloxan and after treatment with both plant extracts. The animals were divided into seven groups, two of which were used for toxicological studies, three were used as control (negative, positive and normal) while the remaining two were used for the test groups. The extracts were found to exhibit hypoglycemic activity in the animals. The results of this study also revealed that the bark extract had more of the antidiabetic properties than the leaf extract as was observed in the change in blood glucose level of the animals in those groups. Histological studies was carried out on various organs of three of the groups among the seven groups (normal control group, group treated with leaf extract and group treated with the bark extract), it was observed that tissue necrosis was more prominent in the organs of the group treated with the leaf extract as compared to those treated with the bark extract when both were compared to the organs of the normal control group. The findings in this study provided the basis for further studies on the plant with the aim of finding out the mechanism of action of the folklore antidiabetic activity and the best extraction method of the toxic compounds without destroying other active components of the plant. Keywords: Jatropha curcas, extracts, alloxan, diabetic. Introduction Diabetes mellitus is a disease characterized by an inability to regulate blood glucose which is caused by a relative or absolute deficiency in insulin. Insulin is a hormone secreted by the β-cells of the pancreas, and is required to utilize glucose from digested food as an energy source (Stong and Story, 2005). There is chronic hyperglycemia in diabetes and is associated with long term damage, dysfunction and failure of different organs, especially the eyes, kidney, nerves, heart and blood vessels (American Diabetes Association, 2012). Several pathogenic processes are involved in the development of Diabetes ranging from autoimmune destruction of the β-cells of pancreas with consequent insulin deficiency to abnormalities that result in resistance to insulin action (American Diabetes Association, 2012). Experimental Diabetes Mellitus has been induced in laboratory animals by several methods. Streptozotocin (STZ) 69% and Alloxan (31%) are by far the most frequently used drugs. Both drugs exert their diabetogenic action when administered parenterally, intravenously, intraperitoneally or subcutaneously (Etuk and Mohammed, 2010). The dose of these agents required for inducing Diabetes depends on the animal specials, route of administration and nutritional status (Balamurugan et al, 2003). Streptozotocin prevents DNA synthesis in mammalian and bacterial cells. In bacterial cells, it renders special reaction with cytosine groups, resulting in degeneration and destruction of DNA with eventual death of mammalian cells. Streptozotocin (STZ) prevents cecullar reproduction with a much smaller dose than the doze needed for inhibiting the substrate connection to the DNA or inhibiting any of the enzymes involves in DNA synthesis (Holam and Vanasscha, 2003). Although, STZ is the most popular drug for induction of Diabetes in rats, there are some disadvantages to its use in chronic experiments especially spontaneous recovery from blood glucose level, by the development of functional insulin (Stemer et al, 1970) and high incidence of kidney and liver tumors. These problems are due strongly to the carcinogenic action of STZ (Anita et al, 2005). Alloxan, a well-known diabetogenic agent is widely used to induce Type-2 Diabetes in animal (Bliss, 2000). Alloxan and its reduction product dialuric acid established a redox cycle with the formation of superoxide radical. These radical undergo dismutation to hydrogen peroxide. The action of reactive oxygen specie (R.O.S) with a simultaneous massive increase in cytosolic calcium concentration causes rapid destruction of B-cells (Chen and Wang, 2005). This alloxan induced Diabetes Mellitus serve as a pathological biomodel for testing a substance with supposed antioxidant activities in-vive (Choi, 2014). Jatropha is a non-edible, oil seed plant from Euphabiacaea family. The plants of this family are an important source of medicine and toxins. The genus Jatropha is widely spread in the tropical regions of the world such as America, Africa and parts of Asian subcontinent. The word Jetropha is derived from a Greek word Jatrus