Effects of valproic acid on the expression of trophic factors in human bone marrow mesenchymal stromal cells

The potential of human bone marrow-mesenchymal stromal cells (hBM-MSCs) to differentiate into diverse cell types and secrete a variety of trophic factors makes them an excellent cell therapy tool for intractable diseases. However, their therapeutic efficacy has not yet been satisfied in preclinical and/or clinical trials with autologous or allogenic stem cells. To improve the efficacy of stem cell therapy, optimized conditions for stem cells need to be defined. In this study, we evaluated the effects of valproic acid (VPA), an HDAC inhibitor, in human BM-MSCs and assessed the expression of trophic factors (ANG, BDNF, ECGF1, bFGF-2, GDNF, HGF, IGF-1, PIGF, TGF-beta 1, and beta-Pix) in MSCs treated with 200 mu g/ml VPA for 12 h. Under these conditions the features of MSCs were not changed. The VPA-treated MSCs also showed an increased cell protective effect against oxidative injuries in MTT assays and improved migratory ability when examined by the Boyden chamber assay. This suggests that MSCs may be improved by treatment with an optimal VPA dose and incubation time, which may increase the efficacy of stem cell therapy. (C) 2012 Elsevier Ireland Ltd. All rights reserved.