Evaluation of in vitro and in vivo anti-urolithiatic activity of silver nanoparticles containing aqueous leaf extract of Tragia involucrata.

The present investigation is focused on exploring the anti-urolithiatic potential of aqueous leaf extract of Tragia involucrata (TIA) and its silver nanoparticles (AgNPs) and to quantify the total phenol, flavonoid, terpenoid and sterol contents present in TIA. Quantification results suggested TIA to be a rich source of phenol, flavonoid and terpenoid and less of sterol content. The AgNPs were synthesized by a simple green method using aqueous extract of T. involucrata. The formation of AgNPs was confirmed through UV spectroscopy, particle size analysis, zeta potential, X-ray diffraction and transmission electron microscopy. The in vitro struvite growth inhibitory activity of the extract was performed using a single gel diffusion method. Samples incorporated with higher concentration of 2% TIA and AgNPs (200 μg mL-1) exhibited potent crystal growth inhibitory activity which was further supported by the dissolution of crystals in gel medium. Calcium oxalate stone formation was induced in rats by the oral administration of ethylene glycol in water. Stone formation was assessed by increase in the levels of calcium and phosphorous in the urine and accumulation of nitrogenous substances like urea, creatinine in renal tissues and blood. Prophylactic treatment with TIA and AgNPs showed significant anti-urolithiatic activity with normalization of the mineral contents of the urine and serum samples. Histopathological analysis of the kidney of TIA- and AgNP-treated animals showed no CaOx deposits and a normal architecture of the kidney cells. We conclude that aqueous extract of T. involucrata and its AgNPs has potential for the treatment of patients with recurrent stones.