Reactive oxygen stress

P450 Mono-oxygenase System Reactive Oxygene Species Oxidative Stress Vitamin C Vitamin E... 

Reactive Oxygen Species Antioxidants Oxidative Stress... 

The protective effects of carotenoids against chronic diseases appear to be correlated to their antioxidant capacities. Indeed, oxidative stress and reactive oxygen species (ROS) formation are at the basis of oxidative processes occurring in cardiovascular incidents, cancers, and ocular diseases. Carotenoids are then able to scavenge free radicals such as singlet molecular oxygen ( O2) and peroxyl radicals particularly, and protect cellular systems from oxidation. 

This situation may be about to change as we look at the role of iron and its implications in the formation of reactive oxygen species, with their potential to attack, modify, and ultimately destroy cells. The signalling function of ROS, not to mention RNS, has been underlined earlier. Yet, we tread a delicate, and poorly understood balance between low levels of ROS, required both for cell signalling and to maintain the antioxidative defences of the cell in a state of alert1"1, and levels which become toxic. This remains an extremely important area of therapeutic concern, since oxidative stress, whether proven to be due to iron or not, is... 

Jiang, M. and Zhang, J. (2002). Water stress-induced abscisic acid accumulation triggers the increased generation of reactive oxygen species and up-regulates the activities of antioxidant enzymes in maize leaves. Journal of Experimental Botany 53 2401-2410. 

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