Quercetin inhibitory potency

The abihty of certain flavonoids to reduce hpid peroxidation in the enzymahc, NADH-dependent model [42,43] most likely involved a dual effect the abihty of the flavonoids to scavenge radicals and a direct inhibition of complex I activity. As discussed earher, complex I achvity is sensihve to most flavonoids in vitro the inhibitory potency is ordy partially dependent on the redox potential of Are compounds. Furthermore, alAiough meAiylahon of a flavonoid such as quercetin promoted its anhperoxidahve effect, it reduced the inhibitory potency of Are flavonoids in relation to complex I and II respirarion [33]. Therefore, it is important to bear in mind that Are protechve vs. toxic effect of a flavonoid may be Are net result of its abihty to inhibit respiratory complexes, scavenge radicals, and influence other mitochondrial funchons. 

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