NAC effect on viability and NO production in CEES/LPS incubated RAW 264.7 cells (NAC pre-treatment). Panel A: Macrophages were pre-treated with or without 10 mM NAC for 5 hours and then incubated with 50 or 100 ng/ml of LPS or/and 500 μM CEES (as indicated) for 24 hours. Cell viability was measured using the MTT assay (see Materials and Methods) and expressed as OD at 575 nm. Panel B: Macrophages were incubated as described above and NO production measured as concentration of nitrite in the culture media as described in Materials and Methods. Mean values not sharing a common letter are significantly different (p < 0.05).