The protective effect of quercetin on long-term alcohol consumption-induced oxidative stress

Mol Biol Rep. 2012 Mar;39(3):2789-94. doi: 10.1007/s11033-011-1037-2. Epub 2011 Jun 15.


Long-term alcohol consumption can cause oxidative stress and cytokines induction, which are associated with free radicals. Quercetin, one of the most widely distributed flavonoids in plants, is a natural antioxidant. We investigated the hypothesis that quercetin could prevent the ethanol-induced oxidative stress and decreases tumor necrosis factor-α (TNF-α) and interferon-γ (INF-γ) as pro-inflammatory cytokines. Twenty-eight rats were randomly divided into control group (C), ethanol treatment group (EtOH) (~1 ml/day, 80%; 2 g/kg body wt), intragastrically (i.g.), quercetin treatment group (Q), (100 mg/kg-body wt per 3 days) i.g. and ethanol plus quercetin treatment group (EtOH + Q) (1 ml/day, 80% of ethanol and 100 mg/kg-body wt of quercetin per 3 days) i.g. for 30 days Plasma thiobarbituric acid reactive substance (TBARS) levels and protein carbonyl content were significantly higher in the EtOH group than the C group (P < 0.01). On the other hand, TBARS level and protein carbonyl content in the EtOH + Q group was decreased significantly by quercetin (P < 0.05, P < 0.01; respectively). While GSH levels in whole blood decreased in EtOH group compared to C group, they increased significantly by quercetin (P < 0.05). Plasma ALT, TNF-α and IFN-γ levels increased significantly in the EtOH group compared to control group (P < 0.05, P < 0.01, P < 0.01, respectively), but they decreased significantly in the EtOH + Q group in comparison with EtOH group (P < 0.05, P < 0.01, P < 0.01, respectively). Our results demonstrate that quercetin treatment may provide a protection as reflected by decreased plasma TBARS, protein carbonyls, TNF-α, INF-γ and ALT levels against ethanol-induced oxidative damage.

MeSH terms

  • Alanine Transaminase / blood
  • Alcohol Drinking / adverse effects*
  • Animals
  • Case-Control Studies
  • Glutathione / blood
  • Interferon-gamma / metabolism
  • Oxidative Stress / drug effects*
  • Protein Carbonylation / drug effects
  • Quercetin / pharmacology*
  • Rats
  • Statistics, Nonparametric
  • Thiobarbituric Acid Reactive Substances / analysis
  • Tumor Necrosis Factor-alpha / metabolism


  • Thiobarbituric Acid Reactive Substances
  • Tumor Necrosis Factor-alpha
  • Interferon-gamma
  • Quercetin
  • Alanine Transaminase
  • Glutathione