MSC Hmox1+/+ strongly induce expression of glutathione pathway enzymes and increase GSH levels after stimulation with hemin. Expression of Gclc
(A), Gclm
(B), Gss
(C), Gsr
(D), Gstp1
(E), and Gstk1
(F) in Hmox1+/+ or Hmox1−/− MSCs or fibroblasts stimulated for 6 h with hemin (50 μmol/L). Ratio of GSH to GSSG (G), changes in total GSH (H), and GSSG (I) in Hmox1+/+ or Hmox1−/− MSCs and fibroblasts stimulated for 6 h with hemin (50 μmol/L) and then kept in fresh medium for 2 h. Levels of GSH and GSSG were measured with GSH/GSSG-Glo™ Assay. Data are shown as mean ± SD, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001 hemin-treated cells versus control; #p < 0.05, ##p < 0.01, ####p < 0.0001 MSC versus fibroblasts, $p < 0.05, $$p < 0.01, $$$p < 0.001, $$$$p < 0.0001 Hmox1+/+ versus Hmox1−/−, Two-way ANOVA with Bonferroni post-test, N = 3. GSH, reduced glutathione; GSSG, oxidized glutathione.