DIFFERENTIAL EFFECT OF ALPHA-TOCOPHEROL AND ASCORBATE ON OXIDATIVE INJURY-INDUCED IN IMMUNE CELLS BY THERMAL-STRESS

As immune cells are often subjected to hyperthermia that can easily oc cur either after intense and/or prolonged exercise or during defense a gainst pathogens, in this paper we analysed whether superoxide anion p roduction occurred in lymphocytes exposed to high temperature and, con sequently, if antioxidants could exert any protective function. The re sults demonstrated that an increase of superoxide anion was induced in rabbit lymphocytes exposed to 42 degrees C for 1h, although cell viab ility was not affected. However suppression of either Pokeweed mitogen (PWM)-driven cell proliferation, or immunoglobulin production or IL-2 synthesis was observed. To evaluate the capacity of antioxidants to r estore the immune suppressed responses, two vitamins, a-tocopherol and ascorbic acid, were added to PWM-stimulated cultures following heat t reatment The data demonstrated that a-tocopherol was able to totally a brogate the inhibitory effects mediated by thermal stress, while ascor bic acid did not give any protective results.