Effect of quercetin and glucuronide metabolites on the monoamine oxidase-A reaction in mouse brain mitochondria

Nutrition. 2011 Jul-Aug;27(7-8):847-52. doi: 10.1016/j.nut.2010.09.002. Epub 2011 Mar 3.


Objective: Quercetin is a flavonoid found in plant foods and herbal medicines. It possesses antidepressant-like effects in forced swimming test-loaded rodents. We wanted to clarify the mechanism of action of dietary quercetin for exerting antidepressant-like effects. The effect of quercetin and its antioxidative metabolite quercetin 3-glucuronide (Q3GA) on the activity of mouse brain mitochondrial monoamine oxidase-A (MAO-A) was evaluated by measuring the deamination product of serotonin, 5-hydroxyindole acetaldehyde (5-HIAL).

Methods: An ultraviolet high-performance liquid chromatographic analysis was applied to measure the 5-HIAL generated by the reaction of MAO-A with serotonin. The inhibitory effect of quercetin and Q3GA on mitochondrial MAO-A activity was estimated by the content of 5-HIAL and hydrogen peroxide accompanied by the MAO-A reaction.

Results: Quercetin (but not Q3GA) decreased the production of 5-HIAL by MAO-A activity. Q3GA inhibited the generation of hydrogen peroxide from the MAO-A reaction with serotonin. A periodic forced swimming test in mice increased brain mitochondrial MAO-A activity. Brain mitochondrial MAO-A activity was decreased in mice administered quercetin for 7 d, but its effect was much weaker than that of the selective MAO-A inhibitor clorgyline.

Conclusion: Quercetin is effective in the modulation of serotonergic activity by attenuating mitochondrial MAO-A activity in the brain. Its antioxidative metabolite Q3GA attenuates oxidative stress by interrupting the generation of hydrogen peroxide accompanying the MAO-A reaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antidepressive Agents / pharmacology*
  • Antidepressive Agents / therapeutic use
  • Brain / drug effects*
  • Brain / metabolism
  • Chromatography, High Pressure Liquid
  • Glucuronides / metabolism
  • Glucuronides / pharmacology
  • Hydrogen Peroxide / metabolism
  • Hydroxyindoleacetic Acid / analogs & derivatives
  • Hydroxyindoleacetic Acid / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Monoamine Oxidase / metabolism*
  • Monoamine Oxidase Inhibitors / pharmacology*
  • Monoamine Oxidase Inhibitors / therapeutic use
  • Phytotherapy
  • Plant Extracts / pharmacology*
  • Plant Extracts / therapeutic use
  • Quercetin / analogs & derivatives
  • Quercetin / pharmacology*
  • Quercetin / therapeutic use
  • Serotonin / metabolism
  • Stress, Psychological / drug therapy
  • Stress, Psychological / metabolism
  • Swimming


  • Antidepressive Agents
  • Glucuronides
  • Monoamine Oxidase Inhibitors
  • Plant Extracts
  • hydroxyindoleacetaldehyde
  • Serotonin
  • Hydroxyindoleacetic Acid
  • Quercetin
  • Hydrogen Peroxide
  • Monoamine Oxidase