Figure 5.

Effect of IAA or H₂O₂ on GSH + GSSG and GSH levels in THP-1 cells. Cells were treated 24 h with (a) IAA or (b) H₂O₂. After this time these compounds were withdrawn and fresh medium was added. GSSG and GSH levels were measured 24 h after the addition of toxic compounds. In addition the effect of NDGA on GSSG + GSH and GSH levels in (c) IAA or (d) H₂O₂ treated cells was also studied. Cells were treated with vehicle or 20 μM NDGA by 12 h; after this the cells were exposed to 5 μM IAA or 1 mM H₂O₂ for 24 h. GSSG and GSH levels were measured 24 h after the addition of toxic compounds. GSH levels were quantified by spectrophotometric/microplate reader assay. Data are expressed as mean ± SEM; n = 3.  *P < 0.05 versus control (without IAA or H₂O₂) and  ⁺ P < 0.05 versus the respective toxic compound.