Figure 6. The effects of lutein, zeaxanthin, or α-tocopherol supplementation on cell viability upon exposure to H₂O₂. A: Subconfluent human lens epithelial cells (HLEC) were incubated with or without 5 µM of lutein, zeaxanthin or α-tocopherol (α-T) for 48 h and then exposed to indicated concentrations of H₂O₂ for 1 h. B: HLEC were cultured with 1 mM D-L(R:S) buthionine sulfoximine (BSO) in the presence of 5 μM lutein, zeaxanthin or α-tocopherol for 48 h. The cells were exposed to the indicated concentrations of H₂O₂ for 1 h in a BSO- and nutrients-free medium. Cell viabilities were determined MTS assay after 20 h recovery in normal medium (n=6). *Indicates that p<0.05 when compared with control group that were not treated with BSO and # indicate a p<0.05 when comparing with the group that was treated with BSO, but not supplemented with any of these nutrients when exposed to the same levels of H₂O₂.