Biological Effects of Quercetin in COPD

Chronic obstructive pulmonary disease (COPD) is a progressive lung disorder and affects millions of people globally. Although the exact mechanisms of pathogenesis of this disease are not well‐understood, the general consensus is that oxidative stress and inflammation induced by exposure to cigarette smoke or other environmental or occupational hazards are responsible for development of COPD. Therefore, therapies aimed at decreasing oxidative stress and inflammation constitutes an important component of treating COPD. The current pharmacological therapies may provide temporary symptom relief, reduce acute exacerbations and hospitalizations, but are associated with side effects. Therefore complementary method of treatment with potentially fewer side effects and relatively well‐tolerated provide promising alternative. One such compound is quercetin, which is plant polyphenol and is present in variety of foods that we consume. Quercetin has potent antioxidant and anti‐inflammatory properties and reduces oxidative stress and inflammation in a preclinical model of COPD. Quercetin exerts it antioxidant properties not only by neutralizing free radical species, but also by enhancing the expression of antioxidant enzymes. Similarly, quercetin inhibits various protein and lipid kinases by competing for adenosine triphosphate (ATP) binding sites thus reducing the inflammatory pathways.