Antihyperuricemic and diuretic effects of procyanidins extracted from Crataegus monogyna

Abstract

Background and objectives: Data indicated that procyanidins extracted from grape seeds has uric acid-lowering effects in mice, however the hypouricaemic effect of procyanidins was not accompanied with changes in enzymatic activities of xanthine dehydrogenase and xanthine oxidase. This study was designed to investigate the effect of procyanidins extracted from Crataegus monogyna on serum uric acid, adenosine deaminase (ADA), 5nucleotidase, xanthine oxidase, and renal function on normal and potassium oxonate induced hyperuricemic rats. Methods: Thirty female albino rats were divided into three groups. The first group included 18 rats pretreated with the uricase inhibitor potassium oxonate (250 mg/kg, i.p.), served as an animal model for hyperuricemia. The rat models were divided into three subgroups, each subgroup having six rats. The first subgroup served as a normal control. Subgroup 2 received a single daily dose (100 mg/kg p.o) of procyanidins for 7 days. The third subgroup received daily dose (50 mg/kg p.o) of allopurinol for 7 days as positive control. The second group included six rats received only water as a vehicle. The serum uric acid, xanthine oxidase, adenosine deaminase (ADA) and 5-nucleotidase levels were measured and compared to those in normal untreated control group. The Third group included six normal rats received a single dose of Procyanidins (50 mg/kg body weight; i.v.) to study the renal effects of procyanidins.. Results: A single daily dose (100 mg/kg PO) of procyanidins for 7 days significantly reduced serum levels of uric acid, ADA and 5’-nucleotidase, without detectable effects on the level of xanthine oxidase in hyperuricemic rats. Intravenous infusion of a single dose of procyanidins (50 mg/kg i.v) produced marked increases in urinary Na + excretion (4.8 folds) and urine flow (2.6 folds) accompanied by insignificant change of potassium excretion in the rats. Conclusion: The reduction in serum uric acid most probably is due to inhibiting enzymes, ADA and 5-nucleotidase. The antihyperuricemic and diuretic effects of procyanidins recommended it as a good drug for the treatment of gout and renal uric acid calculi.