Antihyperglycemic activities of methanolic leaf extract of Anacardium occidentale (Linn.) on the pancreas of streptozotocin-induced diabetic rats

Abstract

Anacardium occidentale is a plant with reported antidiabetic and antioxidant properties. The stem, leave and bark extracts are known to contain saponin, phenolics, flavonoids, vitamins and selenium. Diabetes is a multisystemic disease characterised by defects in insulin secretion or inaction. In this study, forty male Wistar rats (Rattus norvegicus) were randomly divided into four experimental groups A, B, C and D. Hyperglycemia was induced by a single intraperitoneal injection of 70 mg/kg b.w streptozotocin (STZ). Hyperglycemia was confirmed 48 hours later. Five days after, the confirmation of hyperglycemia by using a glucometer (Roche (R) ) and compatible glucose test strips, Groups A and B were treated with 300 mg/kg b.w of A. occidentale extract (AOE) and 1 I U/kg b.w insulin, respectively. Groups C and D served as hyperglycemia and normal controls and received 1 ml/kg b.w citrate buffer, respectively. After 16 days of treatment the animals were sacrificed and the pancreas was processed for histological staining. Data obtained were expressed as means of ten (10) replicates ± SEM and subjected to one way analysis of variance (ANOVA) and the Scheffe’s post hoc test for multiple comparison. Findings showed that STZ-induced diabetes induced hyperglycemia and histopathological changes in the pancreas of untreated rats. Treatment with the methanolic extract of Anacardium occidentale resulted in reduction in hyperglycaemia and regeneration of beta cells.