Reactive oxygen/nitrogen species

Hinson, J.A. Reid, A.B. McCullough, S.S. James, L.P. (2004). Acetaminophen-induced hepatotoxicity role of metabolic activation, reactive oxygen/nitrogen species, and mitochondrial permeability transition. Drug Metabolism Reviews, Vol.36, No. 3-4, (January 2004), pp. 805-822, ISSN 0360-2532. 

Secretion of lysosomal enzymes, reactive oxygen, nitrogen species, and monokines by phagocytic cells... 

Activation of epithelial cells release of reactive oxygen/ nitrogen species causing DNA damages/genetic alteration... 

Oxidation of ascorbic acid by reaction wifii reactive oxygen/nitrogen species in biological fluids - as also shown above for milk leads to its depletion by the reactions. 

The primary sources that are responsible for the presence of this family of compounds in the atmosphere emit NH3, N20, and NO to the troposphere, the lowest level of the atmosphere, which extends to approximately 10 km from the earth s surface. NH3 seems to undergo very little chemistry in the atmosphere except for the formation of aerosols, including ammonium nitrate and sulfates. NH3 and the aerosols are highly soluble and are thus rapidly removed by precipitation and deposition to surfaces. N20 is unreactive in the troposphere. On a time scale of decades it is transported to the stratosphere, the next higher atmospheric layer, which extends to about 50 km. Here N20 either is photodissociated or reacts with excited oxygen atoms, O (lD). The final products from these processes are primarily unreactive N2 and 02, but about 10% NO is also produced. The product NO is the principal source of reactive oxidized nitrogen species in the stratosphere. 

Wiseman H, Halliwell B Damage to DNA by reactive oxygen and nitrogen species role In Inflammatory disease and progression to cancer. BlochemJ 1996 313 17. 

Figure 10.1 Ward cascade showing the cooperation between cytoprotective enzymes and antioxidants for scavenging of reactive oxygen and reactive nitrogen species.

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