title: Protective effect of dietary flavonoid quercetin against lipemic-oxidative hepatic injury in hypercholesterolemic rats.
abstract: BACKGROUND
  Quercetin, a dietary-derived flavonoid, is ubiquitous in fruits and vegetables and plays important roles in human health by virtue of its antioxidant activity.
  
  
  OBJECTIVE
  This study was conducted to investigate the possible modulatory effect of quercetin against hepatic lipemic-oxidative injury in rats fed with a high cholesterol diet (HCD), and to highlight the underlying mechanisms of such effect.
  
  
  METHODS
  Different groups of male Sprague-Dawley rats were used; one group was treated by gavage with HCD cocktail (1 mL/100 g) whereas another group was orally administered HCD-enriched with quercetin (15 mg/kg). Corresponding control animals were also used.
  
  
  RESULTS
  Quercetin administration significantly decreased liver triglycerides (24%), liver total cholesterol (TC) (22%), serum TC (20%), serum low-density lipoprotein cholesterol (31%), and duplicated serum high-density lipoprotein cholesterol (HDL-C). This study also revealed that quercetin administration significantly reduced the activity of serum alanine aminotransferase (41%), aspartate aminotransferase (51%), and γ-glutamyl transpeptidase (G-GT) (35%). Significant inhibition of thiobarbituric acid-reacting substances (40%), together with a valuable enhancement of reduced glutathione (GSH) content (53%) in the liver homogenates, was observed. In addition, quercetin-treated hypercholesterolemic animals exhibited a reasonable improvement of hepatic antioxidant enzymes. Moreover, serum and liver content of nitric oxide (NO) were markedly decreased in this model (26 and 25%, respectively), and were almost normalized following quercetin administration.
  
  
  CONCLUSIONS
  These data revealed that quercetin has the ability to ameliorate HCD-induced lipemic-oxidative injury in rat liver possibly through its antioxidant potential and/or increased NO bioavailability.
authors: Department of Biochemistry, College of Pharmacy, Al-Azhar University, Cairo, Egypt. amrmariee@yahoo.co.uk
authors: Amr D
authors: AD
authors: Mariee
authors: Gamil M
authors: GM
authors: Abd-Allah
authors: Hesham A
authors: HA
authors: El-Beshbishy
mesh_terms: D000818:Animals; D000924:Anticholesteremic Agents / Q000627:therapeutic use*; D000975:Antioxidants / Q000627:therapeutic use*; D002784:Cholesterol / Q000097:blood / Q000378:metabolism; D002791:Cholesterol, Dietary / Q000009:adverse effects; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D019587:Dietary Supplements; D005978:Glutathione / Q000378:metabolism; D006937:Hypercholesterolemia / Q000097:blood / Q000378:metabolism / Q000517:prevention & control*; D008054:Lipid Peroxides / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000097:blood / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011794:Quercetin / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000378:metabolism
chemical_list: D000924:Anticholesteremic Agents; D000975:Antioxidants; D002791:Cholesterol, Dietary; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008054:Lipid Peroxides; D014280:Triglycerides; D009569:Nitric Oxide; D002784:Cholesterol; D011794:Quercetin; D005978:Glutathione