|
Courtesy [9] Origins of reactive oxygen species (ROS) and cellular location |
| Nicotinamide adenine dinucleotide reduced (NADH) |
| NADH Oxidase NADH / NAD+ (mitochondrion, cytosol) |
| NADH + 2O2 → NAD+ + H+ + 2O2- (Super Oxide) |
| Nicotinamide adenine dinucleotide phosphate reduced (NAD(P)H) |
| NAD(P)H Oxidase NAD(P)H / NAD(P)+ (membrane) |
| NAD(P)H + 2O2 → NAD(P)+ + H+ + 2O2- (Super Oxide) |
| Super oxide dismutase (SOD): |
| MnSOD = Mitochondrial SOD |
| CuZnSOD = Intracellular (cytosolic) SOD |
| EcSOD = Extracellular SOD |
| O2- + SOD → H2O2 (hydrogen peroxide) |
| Fenton Reaction: H2O2 + Fe++ → -OH' (the hydroxyl radical) * + Fe+++ + OH- |
| Haber-Weiss Reaction: H2O2 + O2- → -OH- (the hydroxyl radical) + O2 +OH- |
| Peroxynitrite: origins of reactive nitrogen species (RNS) |
| O2- is consumed. Nitric oxide (NO) is also consumed in this process with the creation of reactive nitrogen species (RNS). |
| O2- +NO → ONOO- (peroxynitrite) + tyrosine → nitrotyrosine |
| O2- +NO → ONOO- (peroxynitrite) + arginine → nitroarginine |
| Nitroarginine competes for arginine in the formation of eNO. |
| Nitrotyrosine reflects redox stress and leaves an indelible measurable footprint. |
| NO: the good; O2-: the bad; ONOO-: the ugly [122,9] |
Hayden and Tyagi Cardiovascular Diabetology 2002 1:3 doi:10.1186/1475-2840-1-3 |