Scavenging of peroxynitrite by a phenolic/peroxidase system prevents oxidative damage to DNA

FEBS Letters

Pryor, William A¹  Salgo, Maria G¹  Grace, Stephen C¹ 

[1] Biodynamics Institute, 711 Choppin Hall, Louisiana State University, Baton Rouge, LA 70803-1800, USA

关键词: Antioxidant;    Chlorogenic acid;    DNA damage;    Horseradish peroxidase;    Inflammation;    Myeloperoxidase;    Peroxynitrite scavenging;    Polyphenol;   

DOI  :  10.1016/S0014-5793(98)00298-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We examined the ability of horseradish peroxidase (HRP), an analog of human myeloperoxidase, to protect DNA against oxidative damage caused by peroxynitrite in the presence of chlorogenic acid (CGA), a naturally occurring polyphenol. Chlorogenic acid inhibits the formation of single strand breaks in supercoiled pBR322 DNA by acting as a scavenger of peroxynitrite. Horseradish peroxidase markedly enhances the extent of DNA protection by catalyzing the decomposition of peroxynitrite in the presence of CGA. Horseradish peroxidase alone does not inhibit peroxynitrite-induced DNA strand breaks, indicating that CGA is required as an electron donor to regenerate the active enzyme. The apparent second order rate constant for the HRP-mediated oxidation of CGA in the presence of peroxynitrite at pH 6.9 is 3.4×10⁷ M⁻¹ s⁻¹. This high rate suggests that CGA and other dietary polyphenols might efficiently scavenge peroxynitrite in peroxidase-containing systems in vivo.

【 授权许可】

Unknown