Quercetin

From WikiMD's Wellness Encyclopedia

Quercetin is a plant-derived polyphenolic flavonoid with potential chemopreventive activity. It is abundant in various plant food sources and is a significant bioflavonoid in the human diet. Quercetin exerts various biological effects, including antiproliferative, anti-inflammatory, and anti-allergy actions.

Mechanism of Action[edit | edit source]

While the precise mechanism of action is not fully understood, quercetin has been observed to exert several effects in vitro:

  • Antiproliferative effects: These may result from the modulation of EGFR or estrogen-receptor mediated signal transduction pathways. Quercetin has been observed to decrease the expression of mutant p53 protein and the p21-ras oncogene, which are implicated in cell cycle regulation and tumor progression, respectively.
  • Cell cycle arrest: Quercetin may induce cell cycle arrest at the G1 phase, impeding the progression of the cell cycle and potentially inhibiting the growth of cancer cells.
  • Inhibition of heat shock protein synthesis: Heat shock proteins play a role in protecting cells from stress. Their inhibition by quercetin may make cells more susceptible to the effects of chemotherapeutic drugs.
  • Synergy with chemotherapeutic drugs: Quercetin may enhance the effectiveness of chemotherapeutic drugs and reverse the multidrug resistance phenotype in vitro.

Anti-inflammatory and Anti-allergy Effects[edit | edit source]

Quercetin's anti-inflammatory and anti-allergy effects are thought to be mediated through the inhibition of the lipoxygenase and cyclooxygenase pathways. These enzymes play key roles in the production of pro-inflammatory mediators. By inhibiting these pathways, quercetin can potentially reduce inflammation and allergic reactions.

Food Sources[edit | edit source]

Quercetin is found in various plant-based foods, including apples, onions, berries, red wine, and green tea. Dietary supplements of quercetin are also available.

Further Research[edit | edit source]

While quercetin's potential health benefits are promising, more research is needed to establish its effectiveness and safety in humans, particularly in relation to its potential chemopreventive properties.

See Also[edit | edit source]

Quercetin Resources

Contributors: Prab R. Tumpati, MD