Response of cellular antioxidants to ozone in cultured human fibroblasts

There are some evidence that oxygen-ozone therapy may be beneficial in several human diseases. However the biochemical and pharmacodynamic mechanisms have not been elucidated yet. The ozone therapy is closely related to the "oxidative stress" conception because it generates an effect through the stimulation of antioxidant defence systems against the activity of the noxious oxidative species. Maybe ozone can exert its protective effect by means of an oxidative preconditioning, stimulating and/or preserving the endogenous antioxidant systems. The aim of this work is to evaluate the effects of ozone exposure on antioxidant cellular system in culture of human fibroblast. Normal primary fibroblasts were obtained from healthy donor. Oxygen (O2) or mixture of ozone (O2-O3) were administered (40 or 80 µg/ml) directly on medium for 180 seconds. The fibroblast are tripsinized 30 minutes, 3 hours, 3 day after gaseous exposure. The levels of glutathione reduced (GSH) and oxidized (GSSG), ascorbic acid (AA) and malondialdehyde (MDA) were measured in cells, moreover the concentrations of nitrixc oxide (NO) were evaluated in the medium. The exposures to O2-O3 comparison to control group (cells no exposed) produce an significant increase of GSH (+150 % at 30min, P<0.001), GSSG (+62% at 30min P<0.05), NO (+100% at 3h, P<0.05) levels and a diminution of AA concentrations (-84% P<0.001 after 30 min) and no production of MDA. Our results show that ozone doesn’t induce stress oxidative at used doses and times. On the basis of preliminary data we postulated that ozone administration would promote an oxidative preconditioning preventing the cellular damage. We speculate that effectiveness of ozone could be related to its action on endogenous antioxidants and pro-oxidants balance in favour of antioxidants, explaining thus the good clinical results obtained with ozone therapy.