Project description:Mesenchymal stromal cells (MSCs) hold great promise in the field of liver regenerative medicine. However, the mechanisms and reversibility of hepatogenic differentiation in MSCs are poorly understood. Here, we demonstrate that hepatogenic differentiation of MSCs is a reversible process and is modulated by the transforming growth factor beta 1- DNA methyltransferases (TGF-β1-Dnmts) axis. Dnmt1 and Dnmt3a differentially regulate hepatogenic differentiation and de-differentiation in response to the alternation of TGF-β1 concentration. Knockdown of Dnmt1 accelerates the hepatogenic differentiation in MSCs-derived hepatocyte-like cells (dHeps) whereas Knockdown of Dnmt3a represses hepatogenic differentiation. Conclusions: Our finding first demonstrates that epigenetic regulation by Dnmts in response to stimulation from the surrounding microenvironment controls the reversibility of hepatogenic differentiation in MSCs. Manipulation of Dnmts provides a rapid and efficient differentiation protocol to generate functional dHeps from MSCs that may provide clinical potential for regenerative medicine.
Project description:Mesenchymal stromal cells (MSCs) hold great promise in the field of liver regenerative medicine. However, the mechanisms and reversibility of hepatogenic differentiation in MSCs are poorly understood. Here, we demonstrate that hepatogenic differentiation of MSCs is a reversible process and is modulated by the transforming growth factor beta 1- DNA methyltransferases (TGF-β1-Dnmts) axis. Dnmt1 and Dnmt3a differentially regulate hepatogenic differentiation and de-differentiation in response to the alternation of TGF-β1 concentration. Knockdown of Dnmt1 accelerates the hepatogenic differentiation in MSCs-derived hepatocyte-like cells (dHeps) whereas Knockdown of Dnmt3a represses hepatogenic differentiation. Conclusions: Our finding first demonstrates that epigenetic regulation by Dnmts in response to stimulation from the surrounding microenvironment controls the reversibility of hepatogenic differentiation in MSCs. Manipulation of Dnmts provides a rapid and efficient differentiation protocol to generate functional dHeps from MSCs that may provide clinical potential for regenerative medicine.
Project description:Osteoradionecrosis of the jaw (ORNJ) is a complication after head and neck radiotherapy that severely affects patients’ quality of life. Currently, an overall understanding of microenvironmental factors of ORNJ is still lacking. Here, we reveal the activation of taurine metabolism in irradiated mandibular stromal cells with scRNA-Seq and the decrease of taurine in irradiated bone marrow mesenchymal stromal cells (BMSCs) with metabolomics. Compared to the unirradiated BMSCs, the taurine uptake of irradiated BMSCs increases. The taurine concentration in peripheral blood and jaws of irradiated mice are significantly lower than the unirradiated mice. Supplementation of taurine promotes osteogenic differentiation, decreases oxidative stress and DNA damage of irradiated BMSCs. Oral administration of taurine significantly promotes survival rate of irradiated mice and promotes osteogenesis of irradiated jaws. Our study sheds light on the role of taurine during the recovery of radiation-induced jaw injury, suggesting a potential non-invasive therapeutic means to combat ORNJ.
Project description:Female domestic pigs were fed a 16-week Lean or Obese diet. Mesenchymal stem/stromal cells (MSCs) were harvested from subcutaneous adipose tissue and expanded for 3-4 passages, and 5hmC profiles were examined through hydroxymethylated DNA immunoprecipitation sequencing (hMeDIP-seq) We hypothesized that obesity and cardiovascular risk factors induce functionally-relevant, locus-specific changes in overall exonic coverage of 5hmC in swine adipose-derived MSCs, and evaluated their reversibility using an epigenetic modulator, vitamin-C.
Project description:The polycomb protein Bmi1 restricts adipogenic differentiation of mesenchymal stromal cells to maintain the integrity of hematopoietic stem cell niche.
Project description:Msh homeobox 1 (MSX1) is a transcriptional factor regulating embryonic development of limbs and craniofacial tissues including bone and teeth. The purpose of this study was to investigate contribution of MSX1 to the osteogenic potential and calcification-related phenotypic expression of dental pulp stromal/mesenchymal cells isolated from human teeth. Immunohistochemisitry of a 3 week-old mouse molar showed that MSX1 protein was localized to odontoblasts and pulpal mesenchymal cells at different levels and in different manners depending upon the position of the cells in pulp tissue. When dental pulp stromal/mesenchymal cells were exposed to osteogenesis-induction medium, runt-related transcription factor-2 (RUNX2), bone morphogenetic protein-2 (BMP2), alkaline phosphatase (ALPL) and osteocalcin (OCN) mRNA levels, as well as alkaline phosphatase activity, increased on days 4-12, and, thereafter, the matrix was calcified on day 14. However, knockdown of MSX1 with small interfering RNA abolished this induction of the osteoblast-related gene expression, alkaline phosphatase activity and calcification. Interestingly, DNA microarray and quantative PCR analyses revealed that the MSX1 knockdown induced the sterol regulatory element-binding protein 2 (SREBP2) transcriptional factor and its downstream target genes in cholesterol-synthesis pathway. Inhibition of cholesterol synthesis enhances osteoblast differentiation of various mesenchymal cells. Thus, MSX1 may down-regulate the cholesterol synthesis-related genes to ensure osteoblast differentiation of dental pulp stromal/mesenchymal cells.
Project description:To investigate class A G protein-coupled receptors (GPCR)-targeted drugs in the regulation of osteogenic differentiation, we investigated the effects of drugs using mesenchymal stromal cells.
Project description:Using culture conditions similar to those defined for bone marrow derived mesenchymal stromal cells (BMMSCs), peripheral blood derived mesenchymal stromal cells (PBMSCs) from green fluorescent protein (GFP) transgenic rats were isolated and expanded. Despite the highly similar profile in the putative mesenchymal characteristics including fibroblastic morphology, molecular markers such as CD90, CD44, CD106, vimentin, etc., osteogenic and adipogenic differentiation potentials, significant differential expression between PBMSCs and BMMSCs was discovered in 167 genes by Affymetrix microarray. Of the 167 sequences, were there 81 genes up-regulated and 86 genes down-regulated in the PBMSCs vs BMMSCs. The gene ontological (GO) analysis further revealed that ontology terms such as cell differentiation, development, cell communication, extracellular region, etc., were significantly enriched in these 167 genes, implying potential different biological function of PBMSCs from their counterpart BMMSCs. These genes and associated proteins may also be used as markers for defining PBMSCs from BMMSCs, and more important, may provide further direction to study this elusive cell population. Keywords: mesenchymal stromal cells (MSCs), peripheral blood (PB), bone marrow (BM), green fluorescent protein (GFP) transgenic rat, microarray