Abstract
Incubation of a heavy lysosome-containing (3500×g) fraction from rat liver with ascorbic acid resulted in a marked increase in the formation of lipid peroxides, and a concomitant increase in the release of two marker enzymes, acid phosphatase and aryl sulfatase, from lysosomes. These simultaneous increases in the lipid peroxidation and the lysosomal enzyme release were completely inhibited by adding ethylenediamine tetraacetic acid, indicating that the ascorbic acid-induced lipid peroxidation is responsible for the labilization of lysosomes. Sodium copper chlorophyllin (Cu-Chl-Na) caused a concentration-dependent inhibition of both the lipid peroxidation and the release of marker enzymes which were stimulated by ascorbic acid, and the dose-inhibition curves showed nearly the same pattern. Cu-Chl-Na also prevented the stimulation of lipid peroxidation and release of aryl sulfatase by ferrous ion. These findings indicate that Cu-Chl-Na has the ability to protect liver lysosomes from peroxidative damage, and this effect is ascribed to an inhibition of lipid peroxidation. Cu-Chl-Na also moderately inhibited the release of two marker enzymes from lysosomes in 0.25 and 0.18 M sucrose media, suggesting a direct stabilizing effect of Cu-Chl-Na on the lysosomal membrane.
