Article

Effects of quercetin on liver damage in rats with carbon tetrachloride-induced cirrhosis.

ULBRA-Cachoeira do Sul e Canoas, Brasil.
Digestive Diseases and Sciences (impact factor: 2.12). 05/2003; 48(4):824-9.
Source: PubMed

ABSTRACT Flavonoids are reported to exhibit a wide variety of biological effects, including antioxidant and free radical-scavenging activities. Evidence of oxidative reactions is often associated with various chronic disease processes characterized by accumulation of connective tissue. This study was aimed to investigate the protective effects of chronic administration of the flavonoid quercetin (150 micromol/kg body wt/day intraperitoneally) in rats with carbon tetrachloride-induced fibrosis. In animals rendered cirrhotic by administration of carbon tetrachloride for 16 weeks, cell necrosis, fibrosis, and inflammatory infiltration were found. Histological abnormalities were accompanied by a higher hepatic content of collagen and thiobarbituric acid-reactive substances. Expression of inducible nitric oxide synthase (iNOS) was significantly increased in the liver. Treatment with quercetin during 3 weeks improved liver histology and reduced collagen content, iNOS expression, and lipid peroxidation. Those effects were associated with an increased total peroxyl radical-trapping antioxidant capacity of liver. We conclude that quercetin is effective in this model of liver damage.

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Keywords

150 micromol/kg body wt/day intraperitoneally
 
3 weeks
 
biological effects
 
carbon tetrachloride-induced fibrosis
 
cell necrosis
 
collagen content
 
connective tissue
 
exhibit
 
flavonoid quercetin
 
Flavonoids
 
free radical-scavenging activities
 
higher hepatic content
 
inducible nitric oxide synthase
 
inflammatory infiltration
 
liver damage
 
liver histology
 
protective effects
 
thiobarbituric acid-reactive substances
 
various chronic disease processes
 
wide variety