title: Hypouricemic and antioxidant activities of Allium cepa Lilliaceae and quercetin in normal and hyperuricemic rats.
abstract: OBJECTIVE
  To evaluate the hypouricemic and antioxidant effects of Allium cepa Lilliaceae (Allium cepa L.) and quercetin in normal and hyperuricemic rats.
  
  
  METHODS
  The following study was conducted in the Department of Nutrition and Biochemistry, Tehran University of Medical Science, Iran, between May 2007 and March 2008. A total of 48 male Wistar rats (body weights: 180-200 g) were randomly divided into 8 equal groups including normal; normal + Allium cepa L. (5g/kg); normal + quercetin (5mg/kg); normal + allopurinol (5mg/kg); hyperuricemic; hyperuricemic + Allium cepa L. (5g/kg); hyperuricemic + quercetin (5mg/kg); hyperuricemic + allopurinol (5mg/kg) once a day for 14 days. Experimentally, hyperuricemia in rats was induced by intraperitoneal injection of potassium oxonate (250mg/kg).
  
  
  RESULTS
  Allium cepa L. and quercetin treatments for 14 days significantly reduced (p=0.000) the serum uric acid levels of hyperuricemic rats in a time-dependent manner. All treatments significantly inhibited hepatic xanthine oxidase/xanthine dehydrogenase activity. Allium cepa L. and quercetin treatments led also to a significant improvement in biomarkers of oxidative stress in hyperuricemic rats (p=0.000). Although the hypouricemic effect of allopurinol was much higher than that of Allium cepa L. and quercetin, it could not significantly change oxidative stress biomarkers.
  
  
  CONCLUSIONS
  These results may be responsible partly for the beneficial effects of Allium cepa L. and its major flavonoid on hyperuricemia and oxidative stress.
authors.affiliation: School of Health and Institute of Public Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Haidari
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Rashidi
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Eshraghian
authors.forename: Soltan A
authors.initials: SA
authors.lastname: Mahboob
authors.forename: Majid M
authors.initials: MM
authors.lastname: Shahi
authors.forename: Seid A
authors.initials: SA
authors.lastname: Keshavarz
mesh_terms: D000490:Allium / Q000737:chemistry*; D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D002851:Chromatography, High Pressure Liquid; D033461:Hyperuricemia / Q000188:drug therapy*; D008297:Male; D018384:Oxidative Stress; D011794:Quercetin / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D014527:Uric Acid / Q000097:blood*
chemical_list: D000975:Antioxidants; D014527:Uric Acid; D011794:Quercetin