Use of fluorescent probes to assess the early sulfhydryl depletion and oxidative stress induced by mechlorethamine human bronchial epithelial cells

In this study, we report in vitro methods using fluorescent probes to asses s thiol depletion and the oxidative stress induced by mechlorethamine (HN2) , a nitrogen mustard, on a human bronchial epithelial cell line (16HBE14o-) . Monobromobimane (mBBr) and 2',7'-dichlorofluorescin-diacetate (H2DCF-DA) were respectively used to monitor the intracellular thiol and peroxide leve ls. Fluorescent measurements were realized on gated live cells with a flow cytometer and a microspectrofluorimeter. Results clearly show that HN2 indu ced an early reduction of free sulfhydryl groups inside the cell correlated with an increase in the intracellular peroxides content. HN2 effects were time and dose dependent. The use of these fluorescent probes provide a usef ul and rapid methods for future screening of protective molecules against t he early sulfydryl depletion and oxidative stress induced by HN2 on human a irway epithelium. (C) 1999 Elsevier Science Ltd. All rights, reserved.