Advance in the pharmacological effects of quercetin in modulating oxidative stress and inflammation related disorders

Numerous pharmacological effects of quercetin have been illustrated, including antiinflammation, antioxidation, and anticancer properties. In recent years, the antioxidant activity of quercetin has been extensively reported, in particular, its impacts on glutathione, enzyme activity, signaling transduction pathways, and reactive oxygen species (ROS). Quercetin has also been demonstrated to exert a striking antiinflammatory effect mainly by inhibiting the production of cytokines, reducing the expression of cyclooxygenase and lipoxygenase, and preserving the integrity of mast cells. By regulating oxidative stress and inflammation, which are regarded as two critical processes involved in the defense and regular physiological operation of biological systems, quercetin has been validated to be effective in treating a variety of disorders. Symptoms of these reactions have been linked to degenerative processes and metabolic disorders, including metabolic syndrome, cardiovascular, neurodegeneration, cancer, and nonalcoholic fatty liver disease. Despite that evidence demonstrates that antioxidants are employed to prevent excessive oxidative and inflammatory processes, there are still concerns regarding the expense, accessibility, and side effects of agents. Notably, natural products, especially those derived from plants, are widely accessible, affordable, and generally safe. In this review, the antioxidant and antiinflammatory abilities of the active ingredient quercetin and its application in oxidative stress-related disorders have been outlined in detail.