Protective Role of Urtica dioica methanol extract in treating experimentally induced urinary calculi in rats

Formation of renal calculi is one of the common urological disorders. Urinary stone disorder has always been a common disease currently affecting 10-12% of the population in industrialized countries. The highest prevalence of this disease seems to be at the age of 20-40 years for men, while for the women, the incidence of this disease is somewhat later. Various previous studies have shown that long term exposure to oxalate is toxic to renal epithelial cells and results in oxidative stress. In the present study, methanolic extract of aerial parts of Urtica dioica was screened for antiurolithiatic activity against ethylene glycol and ammonium chloride induced calcium oxalate renal stones in male rats. In the control rats, ethylene glycol and ammonium chloride administration resulted in increased urinary calcium, oxalate and creatinine and renal deposition of calcium and oxalate. Histopathological observations confirmed the induction of lithiasis as calcium oxalate microcrystal deposits were observed in sections of kidney from animals treated with ethylene glycol and ammonium chloride. In the test rats, treatment with methanolic extract of Urtica dioica decreased the elevated levels of urinary calcium, oxalate and creatinine and significantly decreased renal deposition of calcium and oxalate. Renal histological observations exhibited significant reduction in calcium oxalate crystal depositions. In addition, we also carried out the phytochemical analysis of the extract to determine its chemical composition by using LC-ESI-MS-MS as well as HPLC-DAD analytical techniques. The eight chemical constituents identified in the extract were protocatechuic acid, Salicylic acid, Luteolin, Gossypetin, Rutin, Kaempferol-3-O-rutinoside, Kaempferol-3-O-glucoside and Chlorogenic acid. In conclusion, our results suggest that Urtica dioica is embellished with potent antiurolithiatic activity and as such may be considered as a potent natural medicine for various urological disorders.