Antioxidant effect of cirsimarin, a flavonoid extracted from microtea debilis
Résumé
The free radical scavenging activity of cirsimarin was investigated and compared to flavonoids quercetin and genistein. In vitro, cirsimarin induced a dose-dependent inhibition of lipid peroxidation indicating a moderate antioxidant activity (IC(50) = 370 mu M) when compared with genistein (IC(50) = 170 mu M) and quercetin (IC(50) = 1.4 mu M). Adipose tissue has been recently identified as a major site of reactive oxygen species production, the effect of cirsimarin was tested on basal H(2)O(2) production rate of small pieces of rat white adipose tissue. Cirsimarin (15 mu M) induced a 36 % reduction of H(2)O(2) production by adipose tissue. At that concentration it did not scavenge H(2)O(2). These results suggest that cirsimarin exerts a direct action on hydrogen peroxide production by adipose tissue cells.