Fig. 2

Intracellular H₂S (SH⁻) and GSH concentrations produced from NaSH and STS in THP-1 cells (a, c) and U373 cells (b, d) with or without stimulation for 2 days (for THP-1 cells: LPS/IFNγ and for U373 cells: IFNγ). NaSH and STS (100 μM each) were separately added to THP-1 cells. See “Methods” section for details. Values are mean ± SEM, n = 4. Two-way ANOVA was carried out to test significance. Multiple comparisons were followed with post hoc Bonferroni tests. a–d **P < 0.01 for STS-treated groups compared with NaSH groups in the same condition (without stimulants) between 2 and 12 h, ^## P < 0.01 for LPS/IFNγ- or IFNγ-activated groups compared with groups without stimulants between 2 and 12 h, ⁺⁺ P < 0.01 for STS-treated groups compared with NaSH groups in the presence of stimulants between 2 and 12 h. Activation of both cells with stimulants dramatically reduced H₂S and GSH. NaSH was a somewhat more powerful agent than STS, but there was no qualitative difference between the two agents