Diabetes mellitus is a metabolic disorder characterized by the increasing levels of blood glucose as a result of either impaired of insulin secretion, insulin action, or both. Persistent hyperglycemia causes oxidative stress. Aloe vera is known of having an antioxidant activity. One of intrinsic antioxidant enzyme is superoxide dismutase (SOD) which eliminates superoxide radical. This research aims to determine the effect of Aloe vera gel on SOD level in STZ-induced diabetic Wistar rat liver. Wistar strain of Rattus novergicus used in this research were grouped into eight groups, consist of negative control (K-), non diabetic groups (NDM) consist of NDM 1 (dose of 30 mg/day), NDM 2 (dose of 60 mg/day), NDM 3 (dose of 120 mg/day), positive control (DM), and the DM group consists of DM 1 (dose of 30 mg/day), DM 2 (dose of 60 mg/day), and DM 3 (dose of 120 mg/day), with three replications each. Diabetic rats were induced using an intra-peritoneal injection of 60 mg/kg BW STZ. Three milliliters of Aloe vera gel were given intragastrointestinally for 14 days started from three days after injection of STZ. The level of liver SOD was measured with spectrophotometer.The results of One-Way Anova showed that Aloe vera gel has a significant effect on SOD levels (p< 0.05). Further analysis using LSD showed that only the treatment of NDM with 60 mg/day of Aloe vera gel giving a significant decreasing of SOD level compared to (K-). The conclusion is that Aloe vera has potency as a natural antioxidant.

Keywords: Aloe vera, diabetes mellitus, superoxide dismutase (SOD), liver, streptozotocin (STZ) 

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