Effects of Trachyspermum ammi L. (Apiaceae) on serum, urine and hepatic uric acid levels in oxonate-induced rats and in vitro xanthine oxidase inhibition assay.

Invention of many of the new synthetic drugs is based on the knowledge of traditional system of medicine. Trachyspermum ammi L. (Apiaceae) is traditionally used to treat gout and rheumatism. The study was comprised of in vitro determination of total polyphenolic and flavonoid content, xanthine oxidase inhibition assay and in vivo hypouricemic activity of T. ammi in oxonate induced hyperuricemic rat model. In vivo activity consisted of 11 groups of rats each having 6 animals. All the groups except normal control were treated with potassium oxonate. Allopurinol, T. ammi 250 and 500 mg/kg were administered for one, three and seven days (single dose/day) in different study groups (3x3=9 groups). T. ammi has total phenolic content of 145.17 ± 1.70 gallic acid equivalents/g, and the total flavonoid content of 35 ± 2.20 rutin equivalents/g. T. ammi significantly inhibited xanthine oxidase in vitro (IC₅₀= 68.6±0.2 µg/mL). Oral administration of T. ammi significantly reduced serum and hepatic urate levels in hyperuricemic rats in a time-dependent manner. Furthermore, fractional excretion of uric acid was increased. The results suggested that hypouricemic effects of T. ammi could be explained, at least partly, by inhibiting xanthine oxidase in vitro and due to presence of phenolic and flavonoid contents. [ABSTRACT FROM AUTHOR]