Cytochromes P450 and glutathione S-transferases: any association with inflammation and asthma?

Cytochromes P450 and glutathione S-transferases are enzymes involved in the metabolism of xenobiotics. In the lung, they are expressed all throughout the airways, and participate in the metabolism and clearance of numerous to xic xenobiotics. Cytochromes P450 and glutathione S-transferases play thus an important role in detoxication. However, their activity can also lead to the formation of pharmacologically active metabolites or be associated wit h toxic or inflammatory processes. These properties are in favour of a role of cytochromes P450 and glutathione S-transferases in asthma. This role ma y be decreased or increased by environmental pollutants or inflammatory pro cesses that modify cytochrome P450 and glutathione S-transferase expression . Cytochromes P450 and glutathione S-transferases exhibit a genetic polymor phism. In some instances, this polymorphism, explains individual susceptibi lity to the toxic effect of chemicals in the lung. It could also be associa ted with two characteristics of asthma, inflammation and bronchial hyperres ponsiveness. (C) 2001 Editions scientifiques et medicales Elsevier SAS.