Modulatory role of lauric acid supplement on lipid peroxidation and some antioxidant enzymes activity in high fat diet, streptozotocin-induced type 2 diabetic male wistar rats

Abstract

Background: Diabetes mellitus is a major health challenge in the world and is diagnosed by the presence of sustained hyperglycemia (high glucose levels in the blood). Oxidative stress is known to be actively involved in the onset and progression of diabetes and its complications. Antioxidants have important roles in biological systems by scavenging free radicals which may result in oxidative damage of biological molecules such as lipids, proteins and DNA.

Aim: This study was designed to evaluate the effect of lauric acid on lipid peroxidation (serum malondialdehyde concentration) and some antioxidant enzymes (superoxide dismutase and Catalase) activities in high fat diet/streptozotocin-induced type 2 diabetic male wistar rats.

Study Design: Thirty-five apparently healthy male wistar rats aged 6-8 weeks, weighing between 70-90 g were assigned into seven groups of five animals each (n=5) and administered graded doses of lauric acid supplement after validation of diabetes for a period of twenty-one (21) days.

Methodology: Group 1: (Normal control), Group 2: (Diabetic control untreated), Groups 3: (Normoglycemic) received 125 mg/kg Lauric acid, Group 4, 5 and 6 were administered 125, 250 and 500 mg/kg body weight of lauric acid, Group 7: (Standard control) received metformin 100 mg/kg. At the end of twenty-one (21) days, rats were anaesthetized using ketamine and xylazine at 75 and 25 (mg/kg). Blood samples were taken from all treated groups for evaluation of serum MDA, SOD and CAT level.

Results: Serum malondialdehyde (MDA) levels were significantly (P < 0.05) reduced (1.32±0.04, 1.40±0.04 and 1.42 ± 0.06 nmol/l) respectively when compared with the diabetic control (untreated) group with a value of (2.25±0.10 nmol/l), while there was up-regulated activities of serum endogenous antioxidant enzymes: SOD (1.97±0.08, 2.02±0.16, 1.98±0.12 IU/L), CAT (44.5±0.64, 43.2±0.85, 43.7±0.85 IU/L) relative to diabetic control (untreated) (1.35±0.02 and 34.0±0.91 IU/L) respectively.

Conclusion: In conclusion, lauric acid decreases lipid peroxidation while increasing serum antioxidant activity in high fat diet/streptozotocin-induced type 2 diabetic male wistar rats after 21 days oral administration.

Keywords: Lipid peroxidation; antioxidant enzymes; lauric acid; metformin; type 2 diabetes