FIGURE 5.

Lysosomal injury was increased with Hp 2-2-glycosylated Hb complexes incubated with THP-1 differentiated macrophages after loading the cells with LDL, and vitamin E conferred significant protection. Data shown represent the mean ± S.E. of five independent experiments. Three THP-1 differentiated cell groups were used in this experiment before the addition of the different Hp-Hb complexes; THP-1 cells without any treatment, THP-1 cells loaded with native LDL (300 μg/ml) for 24 h and then with acetylated LDL (30 μg/ml) for 6 h, and THP-1 cells prepared the same as the second group except for using vitamin E-enriched LDL (300 μg/ml) instead of native LDL. Lysosomal injury was increased 3-fold in cells loaded with LDL and incubated with Hp 2-2-glycosylated Hb as compared with Hp 1-1-glycosylated Hb (p < 0.001). Vitamin E treatment resulted in ∼40% reduction in lysosomal injury associated with Hp 2-2-glycosylated Hb (p = 0.01). * indicates significant differences between Hp 1-1 and Hp 2-2 within the same cell group. # indicates significant differences between non-LDL- and LDL-loaded cells for each condition. $ indicates significant differences between Vitamin E-LDL- and LDL-loaded cells for each condition. Gly, glycosylated.