Morphological study of the effects of aqueous leaf extract of Xylopia aethiopica on the pancreas in diabetic rats

Abstract

To investigate the histological and immunohistochemical effects of aqueous leaf extract of Xylopia aethiopica on the pancreas in streptozotocin-induced diabetic rats, 30 adult Wistar rats were divided into three groups (n=10). Group A was the control (administered with equivalent volume of citrate buffer), group B animals were made diabetic by a single intraperitoneal injection of streptozotocin dissolved in citrate buffer (65 mg/kg), group C animals were made diabetic as above and treated with 200mg/kg body weight of aqueous leave extract of Xylopia aethiopica for 25 days. Upon animal sacrifice, the pancreas were excised, fixed in 10% formol saline and processed for light microscopy and immunohistochemistry.. The results revealed destruction of the islet cells in the untreated diabetic group as compared with the controls. The extract treated group was characterized by recovery/regenerative processes indicated by improvement in islet morphology. In untreated diabetic rats immunoreactive β-cells were sparse, at variance from the controls. The group treated with aqueous leaf extract of Xylopia aethiopica revealed more intense staining for insulin and significant (p<0.05) increase in the percentage of immuno-labelled surface area when compared with the untreated diabetic group, suggesting the ability of β-cells to secrete insulin in the extract treated rats. We conclude that the aqueous leaf extract of Xylopia aethiopica improves recovery process of β-cells in streptozotocin-induced diabetic rats and might become useful in the management of diabetes related complications.