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 75 mg/kg b.w streptozotocin (STZ). Hyperglycemia was confirmed 48 hrs 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 streptozotocin-induced (STZ-induced) diabetes induced hyperglycemia and histopathological changes iin the pancreas of untreated rats. Treatment with the methanolic extract of Anacardium occidentale resulted in reduction in hyperglycaemia and regeneration of beta cells.