NICANARTINE IMPROVES IN-VITRO RESISTANCE OF LIPOPROTEINS TO OXIDATION

Purpose. The aim of this study is to investigate the plasma protein bi nding of nicanartine and to measure its antioxidant effect on lipoprot eins. Methods. The blood binding was studied with an erythrocyte parti tioning method and the lipoprotein oxidation with the conjugated diene s method. Results. Nicanartine was 24.7% LDL (low density lipoprotein) -bound and 29.2% AAG (alphal-acid glycoprotein)-bound. Nicanartine del ayed but did not stop the oxidation of the three density classes of li poprotein HDL (high density lipoprotein), LDL, VLDL (very low density lipoprotein). The addition of AAG to LDL in the conjugated dienes meth od decreased the nicanartine fraction bound to LDL and decreased its a ntioxidant effect. The decrease of nicanartine LDL-bound fraction and the decrease in antioxidant effect were not parallel. Conclusions. Thi s suggested that (a) AAG-bound nicanartine dissociated to equilibrate the decrease in LDL-bound nicanartine consumed by oxidation, or (b) th e oxidation conditions could involve chemical modifications of nicanar tine and therefore modify its affinity for AAG.