Abstract

Diabetes mellitus is a metabolic disease characterized by hyperglycemia and if not properly controlled, culminates in increased oxidative stress and decrease in anti-oxidant levels. The leaves of Psidium guajava, Anacardium occidentale, Eucalyptus globulus and fruits of Xylopia aethiopica are used in the management of diabetes mellitus and thus, their anti-oxidative effects in alloxan-induced diabetes mellitus in Wister albino rats were investigated using standard methods. The administration of P. guajava, A. occidentale, E. globulus leaf and X. aethiopica fruit extracts caused significant (p<0.05) increases in the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and vitamin C concentration. These increases in some test groups were not significantly (p>0.05) different from those of the glibenclamide groups, with others better increased than the glibenclamide groups. Malondialdehyde (MDA) concentration was significantly (p<0.05) reduced in all the groups except the diabetic-untreated group that showed a marked increase attesting to the fact that peroxidative activity occurred after the induction of diabetes mellitus. In conclusion, the above plants demonstrated anti-oxidative effects and therefore, may be used in the amelioration of disorders associated with oxidative stress.

Key words: Diabetes mellitus, superoxide dismutase, catalase, glutathione.

Abbreviation

Abbreviations: SOD, Superoxide dismutase; CAT, catalase; GPx, glutathione peroxidase; GRx, glutathione reductase; CoQ10, coenzyme Q10; DMSO, dimethyl sulphuroxide; MDA, malondialdehyde; TBARS, thiobarbituric acid reactive substances.