Understanding the cardioprotective effects of flavonols: Discovery of relaxant flavonols without antioxidant activity

Abstract

3′,4′-Dihydroxyflavonol (DiOHF) is a cardioprotective flavonol that can reduce injury after myocardial ischemia and reperfusion and thus is a promising small molecule for the treatment of cardiovascular disease. Like all vasoactive flavonols reported to date, DiOHF is both relaxant and antioxidant, hindering investigation of the relative contribution of each activity for the prevention of reperfusion injury. This study investigates structure-activity relationships of variations at the 3′ and 4′ positions of the B ring of DiOHF and vasorelaxant and antioxidant activities. Relaxation of rat isolated aortic rings precontracted with KCl revealed that the most active flavonols were those with a 4..