Antioxidant Effect of Purple Eggplant Flour (Solanum melongena L.) Against Oxidative Stress in Hyperglycaemic Rats

Abstract

Abstract Background and Aims: Oxidative stress in diabetes mellitus (DM) occurs due to an increase in free radicals and decreased antioxidant defenses including superoxide dismutase (SOD). It causes the occurrence of lipid peroxidation as indicated by the levels of malondialdehyde (MDA). Healthy foods that are rich in antioxidants are needed to reduce oxidative stress, such as eggplant (Solanum melongena L.). Until now there is no scientific evidence about the effects of purple eggplant against oxidative stress in hyperglycemia. The aim of this study is to determine the antioxidant effect of eggplant flour (TTU) against oxidative stress in hyperglycemic rats by induced Nicotinamide-Streptozotocin (NA-STZ). Materials and Method: This experimental study was designed using posttest only. Thirty-six male Sprague Dawley rats, aged 10-12 weeks, body weight (bw) 207.25±26.76 grams were divided randomly into 5 groups, namely 2 control groups (normal and hyperglycemic) and 3 groups of treatment. Hyperglycemic rats were induced by NA-STZ (230-65 mg/kg bw). Administration of TTU through feed for 28 days varied with dose of 2.36 grams, 4.71 grams, and 7.07 grams in groups P1, 2, and 3, respectively. Examinations of blood glucose levels were conducted before intervention, whereas the antioxidant activity of SOD and MDA plasma levels were examined after intervention. Results: The antioxidant activity of SOD in groups which were given TTU was higher than the hyperglycemic rats (31.19±1.98%), but lower than the normal group (220.83±23.68%) Levels of plasma MDA in groups which were given TTU were lower than the hyperglycemic rats (220.47±5.24 nmol/L), but higher than the normal group (1.55±0.20 nmol/L). The antioxidant activity of SOD in the P3 group (69.29±3.82%) was higher than the P1 group (41.84±3.82%) and the P2 group (55.10±3.23%), while the levels of plasma MDA in the P3 group (1.89±0.17 nmol/L) was lower than the P1 group (3.79±0.24 nmol/L) and the P2 group (3.17±0.53 nmol/L). Conclusion: The results of this study demonstrate that administration of TTU significantly prevents oxidative stress in hyperglycemic rats.