ABSTRACT
Oxidation and reduction (redox) are basic chemical reactions of mol ecules in living organisms and are necessary for the generation and uti lization of energy. Much attention has recently been given to the redox event in controlling gene usages (1-5). Oxidative stress on cells through environmental agents such as oxidants (6-12), nitric oxide (NO) (1315), ultraviolet (UV) radiation (16), alkylating agents (8,17-19) and heavy metals (18,20-26) regulates the signal transduction for gene ac tivation, possibly through changing the intracellular redox level. More over, there is evidence that reactive oxygen intermediates (ROI) may work as second messengers of the receptor-mediated signal. Interaction of inflammatory cytokines (27), insulin (28), and platelet-derived growth factor (29) with their receptors on cells thus generates ROI, and antioxidants inhibit the receptor-ligand interaction-mediated activation of Syk tyrosine kinase (30).
