Diuretic activities of hydro-alcoholic extract and solvent fractions of the roots of Withania somnifera L. (Solanacaea) in rats

Abstract

Background: Withania somnifera (Local name ‘Gsawa’) is used in folkloric medicine for the management of hypertension in different parts of the world including Ethiopia. This may be due to its diuretic activity. However, it has not been yet scientifically validated for its efficacy and safety. Objective: The aim of this study was to investigate the diuretic potential of both hydro-alcoholic (80% methanol) extract and solvent fractions of the hydro-alcoholic root extract of W. somnifera in rats. Results: The hydro-alcoholic extract increased diuresis significantly at the doses of 400 and 600mg/kg (p<0.05). Similarly, the solvent fractions of the hydro-alcoholic extract -the aqueous and n-butanol fractions- significantly increased urine volume at 400mg/kg (p<0.05). Regarding electrolyte excretion, the larger doses of both hydro-alcoholic extract and aqueous fraction increased natriuresis (p<0.05). Phytochemical analysis revealed the presence of secondary metabolites including tannins, terpenoids, flavonoids and saponins, which could be the responsible component (s) for the diuretic activity. Conclusion: The results of the present study indicated that the W. somnifera extract is endowed with significant diuretic activity providing evidence for its traditional claim. The increased diuresis effects of the crude extracts and fractions may be attributable for presence of polar phytoconstitutents. Background: Withania somnifera (Local name ‘Gsawa’) is used in folkloric medicine for the management of hypertension in different parts of the world including Ethiopia. This may be due to its diuretic activity. However, it has not been yet scientifically validated for its efficacy and safety. Objective: The aim of this study was to investigate the diuretic potential of both hydro-alcoholic (80% methanol) extract and solvent fractions of the hydro-alcoholic root extract of W. somnifera in rats. Results: The hydro-alcoholic extract increased diuresis significantly at the doses of 400 and 600mg/kg (p<0.05). Similarly, the solvent fractions of the hydro-alcoholic extract -the aqueous and n-butanol fractions- significantly increased urine volume at 400mg/kg (p<0.05). Regarding electrolyte excretion, the larger doses of both hydro-alcoholic extract and aqueous fraction increased natriuresis (p<0.05). Phytochemical analysis revealed the presence of secondary metabolites including tannins, terpenoids, flavonoids and saponins, which could be the responsible component (s) for the diuretic activity. Conclusion: The results of the present study indicated that the W. somnifera extract is endowed with significant diuretic activity providing evidence for its traditional claim. The increased diuresis effects of the crude extracts and fractions may be attributable for presence of polar phytoconstitutents. Background: Withania somnifera (Local name ‘Gsawa’) is used in folkloric medicine for the management of hypertension in different parts of the world including Ethiopia. This may be due to its diuretic activity. However, it has not been yet scientifically validated for its efficacy and safety. Objective: The aim of this study was to investigate the diuretic potential of both hydro-alcoholic (80% methanol) extract and solvent fractions of the hydro-alcoholic root extract of W. somnifera in rats. Results: The hydro-alcoholic extract increased diuresis significantly at the doses of 400 and 600mg/kg (p<0.05). Similarly, the solvent fractions of the hydro-alcoholic extract -the aqueous and n-butanol fractions- significantly increased urine volume at 400mg/kg (p<0.05). Regarding electrolyte excretion, the larger doses of both hydro-alcoholic extract and aqueous fraction increased natriuresis (p<0.05). Phytochemical analysis revealed the presence of secondary metabolites including tannins, terpenoids, flavonoids and saponins, which could be the responsible component (s) for the diuretic activity. Conclusion: The results of the present study indicated that the W. somnifera extract is endowed with significant diuretic activity providing evidence for its traditional claim. The increased diuresis effects of the crude extracts and fractions may be attributable for presence of polar phytoconstitutents.