Signalling pathways involved in cigarette smoke induced-oxidative stress and apoptosis in human lymphocytes

Although, health effects of cigarette smoke (CS) in humans are well known, the mechanism behind CS toxicity remains mainly unknown, partly due to its chemical complexity. In the cur-rent study we investigated the effect of CS and CS gas phase on human T-lymphocytes oxidation and apoptosis. Cells were exposed to various concentrations of CS (1-5 puffs). Both apoptosis and oxidative stress exhibited a dose-response relationship with CS concentrations. In order to evaluate which signal transduction pathways were involved, focus was given on the kinase and the protease cascade. Therefore MAP kinase and caspase-3 activation were examined in lymphocytes exposed to CS. Activation of both cascades was evident when cells were exposed to CS, while only the kinase pathway seemed to be activated when cells were exposed to CS gas phase.