Evaluation of Efficacy of Cucumis melo in Gentamycin and CPD Induced Urolithiasis on Rats

Evaluation of the efficacy of methanolic extract of Cucumis melo in urolithiasis induced by gentamycin and calculi producing diet on Wistar rats. Gentamycin (40 mg/kg, subcutaneously) and calculi-producing diet (CPD) was fed to induce urolithiasis on Wistar rats. The effect of oral administration of methanolic extract of Cucumis melo seed on calcium oxalate urolithiasis has been studied and is compared with the effect of oral administration of Cystone as standard on Wistar rats. Gentamycin and CPD feeding resulted in hyperoxaluria and calcium oxalate deposition as well as increased renal excretion of calcium and oxalate. Supplementation with methanolic extract of Cucumis melo seed reduced the elevated urinary oxalate, showing a regulatory action on endogenous oxalate synthesis. The results indicate that the seed of Cucumis melo is endowed with antiurolithiatic activity. Keywords: C. melo, Hyperoxaluria, calcium oxalate deposition, cystone, hyperoxaluria, analysis of variance

Interactive effect of nitrogen nutrition, nitrate reduction and seasonal variation on oxalate synthesis in leaves of Napier-bajra hybrid (Pennisetum purpureum × P. glaucum)

Oxalate may cause hypocalcaemia or formation of urinary calculi in animals with prolonged grazing of Napier grass (Pennisetum purpureum) × pearl millet (bajra, P. glaucum) hybrid (NBH). We investigated the influence of nitrate metabolism, nitrogen (N) nutrition, N forms and seasonal variation on oxalate accumulation in leaves of NBH in a field experiment in Ludhiana, India. The experiment was a randomised block design with three N sources (nitrate, amide and ammonium), three application rates (50, 75 and 100 kg N/ha), four seasons (summer, monsoon, autumn, pre-winter) and three replicates. Applied N nutrition induced oxalate synthesis and activities of nitrate reductase (NR) and nitrite reductase (NiR) enzymes. A positive association of N nutrition with both oxalate accumulation and nitrate-reducing enzymes was found. Nitrate-N increased oxalate accumulation and NiR activity more than ammonium and amide. A differential effect of seasons on NR and NiR activities, as well as on oxalate accumulation, was observed. Among different harvest seasons, NR and NiR activities were positively associated with oxalate accumulation in summer and the monsoon season. These results suggest that N fertilisation, particularly in nitrate form, is associated with upregulation of nitrate-reducing enzymes, leading to oxalate accumulation in NBH leaves.