Synthesis of HGF and TSG-6 by BM-MSCs and the signaling pathways involved.

<p>(A) Western blot analysis of signaling pathways in BM-MSCs mono-culture. BM-MSCs were incubated with HSA (2 mg/ml) for 0–120 min. Total protein from BM-MSCs was collected and subjected to Western blotting for ERK, NF-κB and p38 signals. (B and C) Dose effect of HSA on mRNA and protein expression of HGF. BM-MSCs were exposed to increasing doses of ambient albumin (from 1 to 10 mg/ml) for 6 h (for real-time PCR) or 24 h (for ELISA assay). (D and E) Dose effect of albumin on mRNA and protein expression of TSG-6. BM-MSCs were incubated with HSA (2 mg/ml) for 6 h. All results represent means ±SD from 3 independent experiments. *<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.001 versus medium control. (F and G) Effect of the corresponding inhibitors on HSA-induced HGF and TSG-6 expression. BM-MSCs were treated for 6 h with medium control, HSA (2 mg/ml), the ERK inhibitor PD98059 (10 µM, added 1 h before the addition of HSA), the NF-κB inhibitor PDTC (25 µM, added 1 h before the addition of HSA) or the p38 inhibitor SB203580 (25 µM, added 1 h before the addition of HSA). <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090883#s3" target="_blank">Results</a> are mean ±SD from 3 independent experiments. <i>n.s.</i> indicates no significant difference. * and *** denote significant differences at <i>P</i><0.05 and <i>P</i><0.001, respectively.