VITAMIN-E PREVENTS OXIDATIVE MODIFICATION OF BRAIN AND LYMPHOCYTE BAND-3 PROTEINS DURING AGING

Antioxidants may play an important role in preventing free radical dam age associated with aging by interfering directly in the generation of radicals or by scavenging them. We investigated the effects of a high vitamin E and/or a high beta-carotene diet on aging of the anion tran sporter, band 3, in lymphocytes and brain. The band 3 proteins functio n as anion transporters, acid base regulators, CO2 transporters, and s tructural proteins that provide a framework for membrane lipids and th at link the plasma membrane to the cytoskeleton. Senescent cell antige n (SCA), which terminates the life of cells, is a degradation product of band 3. This study was conducted as a double-blind study in which e ight groups of middle-aged or old mice received either high levels of beta-carotene and/or vitamin E or standard levels of these supplements in their diets. Anion transport kinetic assays were performed on isol ated splenic lymphocytes. Immunoreactivity of an antibody that recogni zes aging changes in old band 3 preceding generation of SCA was used t o quantitate aged band 3 in brain tissue. Results indicate that vitami n E prevented the observed age-related decline in anion transport by l ymphocytes and the generation of aged band 3 leading to SCA formation. beta-Carotene had no significant effect on the results of either assa y. Since increased aged band 3 and decreased anion transport are initi al steps in band 3 aging, which culminates in the generation of SCA an d cellular removal, vitamin E prevents or delays aging of band 3-relat ed proteins in lymphocytes and brain.