Induction of osteogenic differentiation of human mesenchymal stem cells by histone deacetylase inhibitors

Abstract

Valproic acid (VPA) has been used as an anticonvulsant agent for the treatment of epilepsy, as well as a mood stabilizer for the treatment of bipolar disorder, for several decades. The mechanism of action for these effects remains to be elucidated and is most likely multifactorial. Recently, VPA has been reported to inhibit histone deacetylase (HDAC) and HDAC has been reported to play roles in differentiation of mammalian cells. In this study, the effects of HDAC inhibitors on differentiation and proliferation of human adipose tissue-derived stromal cells (hADSC) and bone marrow stromal cells (hBMSC) were determined. VPA increased osteogenic differentiation in a dose dependent manner. The pretreatment of VPA before induction of differentiation also showed stimulatory effects on osteogenic differentiation of hMSC. Trichostatin A (TSA), another HDAC inhibitor, also increased osteogenic differentiation, whereas valpromide (VPM), a structural analog of VPA which does not possess HDAC inhibitory effects, did not show any effect on osteogenic differentiation on hADSC. RT-PCR and Real-time PCR analysis revealed that VPA treatment increased osterix, osteopontin, BMP-2, and Runx2 expression. The addition of noggin inhibited VPA-induced potentiation of osteogenic differentiation. VPA inhibited proliferation of hADSC and hBMSC. Our results suggest that VPA enhance osteogenic differentiation, probably due to inhibition of HDAC, and could be useful for in vivo bone engineering using hMSC.

Housekeeping gene stability influences the quantification of osteogenic markers during stem cell differentiation to the osteogenic lineage

“…Later reports, as the one by Catelas et al (2006), also used 18S rRNA as a normalizer gene under similar experimental conditions. Other studies, as recent as the works by Cho et al (2005), Abdallah et al (2005) and Friedman et al (2006), used ACTB for normalizing the gene expression levels of hBMSCs under osteogenic conditions. Other contemporary publications reported the use of GAPDH for normalization purposes with hBMSCs and osteogenic conditions (Mbalaviele et al 2005;Sumanasinghe et al 2006;Tsukahara et al 2006).…”

“…To address this issue, this work aimed to study the stability of two of the most commonly used housekeeping genes in osteogenic differentiation studies of stem cells: ACTB and GAPDH (Vandesompele et al 2002;Cho et al 2005;Mbalaviele et al 2005), in hBMSCs undergoing osteogenic differentiation. The results were compared with the stability of the gene ribosomal protein L13A (RPL13A), which has been shown to have stable expression levels in bone marrow tissues (Vandesompele et al 2002).…”

In vitro differentiation of hepatic progenitor cells from mouse embryonic stem cells induced by sodium butyrate

“…Much is known about the mechanism of HDAC inhibitors effect on the transformed cells, however, little is known about the functional mechanism that exerts antiproliferative, induction of differentiation or apoptotic effects on the normal cells. Recently, HDAC inhibitors have been reported to inhibit cardiomyocyte differentiation of embryonic stem cells [Na et al, 2003], myofibroblastic differentiation of rat hepatic stellate cells [Niki et al, 1999], mediated neuronal differentiation of multi-potent adult neural progenitor cells [Hsieh et al, 2004], induction of osteogenic differentiation of human mesenchymal stem cells [Cho et al, 2005], and enhances the cytokine-induced expansion of human hematopoietic stem cells [De Felice et al, 2005]. According to our data, the differentiation system with the treatment of sodium butyrate allows ES cells differentiation into hepatic progenitor cells, moreover, VPA, another reported type II HDAC inhibitors, had similar effects on the process of differentiation (data not shown).…”

“…In addition, the majority of the treated cells remained in cell cycle for 3 days after the addition of sodium butyrate, but the cycling fraction decreased to 17% 7 days later [Rambhatla et al, 2003]. It was now established that treatment of cells both in vitro and in vivo with sodium butyrate, a potential histone deacetylase (HDAC) inhibitor, could result in specific functional outcomes such as proliferation, cell cycle arrest, apoptosis, or differentiation [Janson et al, 1997;Sambucetti et al, 1999;Wang et al, 1999;Travers et al, 2002;Camphausen et al, 2004;Hsieh et al, 2004;Bug et al, 2005;Cho et al, 2005;Jiang et al, 2005;Rossig et al, 2005]. Therefore it was assumed that the treatment with sodium butyrate would lead to the cell cycle arrest of the ES cells, and the removal of sodium butyrate might be important for the treated cells to reenter into cell cycle and consequently the cells with the capacity to proliferate and express hepatic linage markers could be acquired.…”

The Epigenetics of Adult (Somatic) Stem Cells

“…85 Consistent with this is the observation that the HDAC inhibitors valproic acid and trichostatin A promote osteogenesis by human MSCs in a bone morphogenetic protein-dependent manner in vitro. 86,87 These findings suggest that HDAC inhibitors could enhance regeneration in bone, but further in vitro and in vivo studies will be necessary. 86 Although the mechanisms accounting for osteogenic promotion are unknown, several possibilities merit further consideration.…”