Attenuation of Oxidative Damage in Alloxan Induced Diabetic Rabbits Following Administration of the Extract of the Leaves of Vernonia amygdalina.

Abstract

Introduction: Diabetes is a disease that constitutes multiple sources of free radicals, thus oxidative stress is expected to have a double impact. Since oxidative stress is mediated by hyperglycemia-induced generation of free radical, it is supposed that compounds with hypoglycemic and antioxidative properties would be useful antidiabetic agents. Our study investigated the use of V. amygdalina as a potential hypoglycemic and antioxidative agent by testing its effect on the antioxidant biomarkers and lipid peroxidation. Methods: Dried leaves of V. amgydalina were extracted for 48 hrs and freeze dried. Acute toxicity was investigated in 25 rats. Thirty six rabbits were divided into 6 groups: groups I -III were normal; diabetes was induced in groups (IV -VI). Groups I and IV were normal and diabetic controls respectively. The animals were treated with aqueous leaf extract of V. amygdalina. Blood samples were collected and used for the study. Results: The reduction in body weight in the diabetic groups was regained following administration of the extract of V. amgydalina. The extract is considered safe and had little or no effect on blood glucose, MDA and GSH levels of the normal rabbits. Extract significantly reduced glucose and MDA concentrations but increased GSH levels in the diabetic rabbits. Similarly, the extract had no effect on the activities of SOD, CAT and GPx in normal rabbits, however in diabetic rabbits, the enzymes activities increased dose-dependently. Conclusion: This finding provides basis for the use of V. amgydalina as potential antidiabetic antioxidant agent and may be useful for its hypoglycemic property. INTRODUCTIONWith oxidative stress linked to metabolic or vascular disorder, diabetes becomes the best disease for studying the consequences of oxidative stress and its treatment. Diabetes mellitus is a multifactorial disease characterized by hyperglycemia, [2,3] lipoprotein abnormalities, [4] raised basal metabolic rate, [5] defect in reactive oxygen species scavenging enzymes [6] and high oxidative stress induced by the generation of highly reactive free radicals which are also involved in pancreatic destruction. [2,7] Insufficient removal of these free radicals can lead to oxidative damage to membranes; enhance susceptibility to lipid peroxidation, enzyme inactivation and nucleic acid damage. [8,6] Since oxidative stress is mediated by hyperglycemiainduced generation of free radical, it became clear that lowering blood glucose as well as scavenging the free radicals may ameliorate the oxidative stress thus providing an effective strategy for reducing diabetic mellitus and its complications. Attenuation of Oxidative Damage in Alloxan Induced[9] Hence compounds with both hypoglycemic and antioxidative properties would be very useful antidiabetic agents. We therefore considered a known hypoglycemic plant, Vernonia amygdalina and its effect on some endogenous biomarkers of oxidative stress: superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) and lipid peroxidation...

Comparative Effect of Vernonia Amygdalina and Metformin in Alloxan Induced Diabetes Mellitus

“…Vernonia amygdalinahave been shown to possess similar antihyperglycaemic effect (Akah et al, 2002;Onahinon et al,2018). VA have been shown to reverse oxidative stress imposed on pancreatic beta cell by alloxan (Owolabi et al,2011;Onahinon et al,2018). The reduction of fasting blood glucose by VA in alloxan induced diabetes is as a result of several active constituents that have been reported to be present in VA extract (Mukwaya et al,2016).…”

Sargassum polycystum extract attenuates oxidative stress on diabetic rats

“…There is decreasing of oxidative stress caused by free radicals in diabetes mellitus was corrected by antioxidant agent administration [8]. To elucidate the contribution of antioxidant agent to oxidative stress improving in diabetes mellitus, we studied the effect of S. polycystum extract on the level of lipid peroxidation product, MDA which results from attacking of free radical to membrane components of the cells [5]. The mean level of MDA increased significantly (P ≤ 0.05) in the diabetic control compared to the normal group indicating increased oxidative stress in the diabetic rats.…”

“…In diabetes mellitus, free radical could be produced by many mechanisms, for example, autooxidation of glucose, induction and activation of various lipoxygenase enzymes, activation of glycation pathways, promotion of the interaction of nitric oxide with superoxide anions to produce peroxynitrite and hydroxyl radicals and reduction of the activity of the antioxidant defense mechanisms [4]. Insufficient of reduction blood glucose level and removal free radical might lead to lipid peroxidation and enzyme inactivation and finally inducing diabetic complications [2,[5][6].…”

Evaluation of the Antihyperlipidemic and Antioxidant Properties of the Aqueous Leaf Extract of Camellia sinensis in Oil-induced Hyperlipidemic Rats

“…Lipid peroxidation was determined by measuring the level of malondialdehyde (MDA) as an indicator of lipid peroxidation using the method of Owolabi et al 26 Briefly, 1 mL of plasma was precipitated with 0.5 mL, 14% trichloroacetic acid and centrifuged at 3000 x g for 15 min and supernatant separated. To the supernatant was added 0.5 mL glacial acetic acid and 0.5 mL thiobarbituric acid (0.6% w/v).…”