Fig. 3
BMSCs inhibit neutrophil infiltration into liver, MPO activity, MDA expression, and neutrophil oxidative burst via HO-1 induction in D-Gal/LPS-induced ALF. a Myeloperoxidase (MPO, a neutrophil marker) staining (brown) in livers 72 h after D-Gal/LPS (magnification × 400). b Number of MPO-positive cells in each group (n = 6 per group). ALF rats had the most MPO-positive cells, BMSCs infusion significantly decreased the number of MPO-positive cells (p < 0.05). Znpp resulted in more MPO- + cells than BMSC alone (p < 0.05). c MPO activity was significantly increased by D-Gal/LPS vs. control rats (p < 0.05). BMSCs decreased MPO activity induced by ALF (p < 0.05); Znpp blunted the BMSC effect. Hemin treatment after BMSC was also associated with reduced MPO activity (p < 0.05) (n = 6 per group). Livers collected 24 and 72 h following D-Gal/LPS. d Malondialdehyde (MDA) levels (n = 6 per group) were increased significantly in ALF livers. BMSCs significantly reduced MDA expression after ALF (p < 0.05). Znpp administration blunted the effect of BMSC (p < 0.05). Hemin treatment after BMSC was also associated with decreased MDA levels (p < 0.05). e R123 fluorescence of neutrophils (oxidative stress) at 24 h and 72 h after D-Gal/LPS (n = 6 per group). Fluorescence intensity increased significantly in ALF livers. BMSCs infusion resulted in a significant reduction of fluorescence intensity (p < 0.05), whereas Znpp administration blunted the BMSC effect on fluorescence (p < 0.05). Hemin after BMSC was also associated with decreased fluorescence vs. ALF (p < 0.05), f Quantitative reverse transcription PCR for mRNA levels of CXCL1, CXCL2, and CXCL12 in livers. CXCL1 and CXCL2 expression increased significantly in ALF livers (p < 0.05). BMSCs infusion decreased the mRNA levels of CXCL1 and CXCL2 vs. ALF levels (p < 0.05); Znpp administration blunted the effects of BMSCs only on CXCL1 mRNA expression (p < 0.05). Hemin treatment after BMSC was also associated with decreased CXCL1 and CXCL2 mRNA vs. ALF (p < 0.05). Treatment groups: control, ALF, ALF followed by intravenous MSCs (ALF + MSC) 1 h post-induction, ALF followed by MSCs and Znpp (ALF + MSC + Znpp) 1 h post-induction, and ALF followed by hemin (ALF + hemin) 1 h post-induction. Data are mean ± SD. (* p < 0.05 vs. control group; $ p < 0.05 vs. ALF group; # p < 0.05 vs. ALF + MSC group). Abbreviations: ALF acute liver failure, BMSCs bone marrow-derived mesenchymal stem cells, D-Gal d-Galactosamine, FITC fluorescein isothiocyanate, HO-1 heme oxygenase-1, LPS lipopolysaccharide, Znpp zinc protoporphyrin