Insulin and alpha amylase levels in alloxan-induced diabetic rats and the effect of Rothmannia hispida (K. Schum) Fagerl leaf extract

Abstract

Objectives: Rothmannia hispida (R. hispida) is used in West African traditional medicine for the treatment of various ailments such as fever, dysentery, skin infections, abdominal pain and diabetes mellitus. To elucidate the pharmacological basis of the antidiabetic efficacy of this plant drug, the effect of R. hispida on insulin and alpha amylase levels were examined in alloxan-induced diabetic rats. Method: Diabetic rats were treated with leaf extract of R. hipida at dose levels of 250mg/kg and 500mg/kg respectively. The concentration of insulin in serum samples was estimated using Enzyme-Linked Immunoabsorbent Assay (ELISA) method using insulin kit (Syntron Bioresearch, USA), alpha amylase levels were estimated using routine biochemical procedures. Results: Treatment of alloxan diabetic rats with leaf extract of R. hipida significantly (p<0.001) reduced hyperglycaemia, significantly (p<0.001) attenuated alloxan-induced hypoinsulinaemia and significantly (p<0.01) increased alpha amylase levels compared with diabetic untreated rats. Conclusion: It is concluded that increased insulin secretion and/or increased alpha amylase synthesis sequel to enhanced liver glucose entry by Rothmannia hispida is proposed to be the mechanism by which this herbal plant exhibits its antidiabetic effect.