Cytotoxicity of nitroaromatic

Ascorbate Potentiated Cytotoxicity of Nitroaromatic Compounds. Extensive research aimed at finding chemicals or chemical systems that will sensitize hypoxic cells, which are ordinarily very resistant to radiation or chemicals, is being conducted in the field of radiobiology. Of particular interest are the investigations (58-6J) of the catalytic effect of certain carcinogens upon the oxidation of ascorbate. 4-Nitroquinoline N-oxide (4-NQO), which is one of many compounds (52,62,63) that mediate the ascorbate-oxygen reaction, is used as an example. 

Cenas N et al., Quantitative structure-activity relationships in enzymatic single-electron reduction of nitroaromatic explosives Implications for their cytotoxicity, Biochim. Biophys. Acta., 1528, 31, 2001. 

In this section, we present the data on the enzymatic reactions of explosives relevant to the general cytotoxicity mechanisms of nitroaromatics (1) their single-electron enzymatic reduction to radicals accompanied by the formation of the reactive oxygen species (oxidative stress type of cytotoxicity) and (2) their two-electron reduction to nitroso and hydroxylamino metabolites causing the cytotoxicity by their covalent binding to proteins and DNA. 

Concentrations of Nitroaromatic Explosives and Their Metabolites for the 50% Cell Survival (LC50) in Mammalian Cell Culture Cytotoxicity Studies... 

The nitroaromatic and nitro-nonbenzenoid compounds considered in this chapter share a commonality of cytotoxic mechanisms that initially involve one or more reductive reactions on the nitro group, followed by various enzyme inhibitions necessary for the parasitic cell s energy requirements. An understanding of some of the differences between mammalian and microbial cells may explain the favorable selective toxicity these drugs exhibit. 

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