Quercetin nitric oxide protection

The administration of Qio or quercetin to rats protected against endotoxin-induced shock in rat brain [252]. It was found that the pretreatment with these antioxidants diminished the shock-induced increase in brain MDA and nitric oxide levels. Interesting data have been obtained by Yamamura et al. [253] who showed that ubiquinone Qi0 is able to play a double role in mitochondria. It was found that on the one hand, Q10 enhanced the release of hydrogen peroxide from antimycin A- or calcium-treated mitochondria, but on the other hand, it inhibited mitochondrial lipid peroxidation. It was proposed that Q10 acts as a prooxidant participating in redox signaling and as an antioxidant suppressing permeability transition and cytochrome c release. 

Duarte J, Jimenez R, O Valle F, Galisteo M, Perez-Palencia R, Vargas F, Perez-Vizcaino F, Tamargo J. 2002. Protective effects of the flavonoid quercetin in chronic nitric oxide deficient rats. J Hypertens 20 1843-1854. 

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