Human Urothelial Cells Isolation, In Vitro Expansion and Characterization for Evaluating Bio-Engineering Potentials

Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and have diverse functions during development and organogenesis. BMPs play a major role in skeletal development and bone formation, and disruptions in BMP signaling cause a variety of skeletal and extraskeletal anomalies. Several knockout models have provided insight into the mechanisms responsible for these phenotypes. Proper bone formation requires the differentiation of osteoblasts from mesenchymal stem cell (MSC) precursors, a process mediated in part by BMP signaling. Multiple BMPs, including BMP2, BMP6, BMP7 and BMP9, promote osteoblastic differentiation of MSCs both in vitro and in vivo. BMP9 is one of the most osteogenic BMPs yet is a poorly characterized member of the BMP family. Several studies demonstrate that the mechanisms controlling BMP9-mediated osteogenesis differ from other osteogenic BMPs, but little is known about these specific mechanisms. Several pathways critical to BMP9-mediated osteogenesis are also important in the differentiation of other cell lineages, including adipocytes and chondrocytes. BMP9 has also demonstrated translational promise in spinal fusion and bone fracture repair. This review will summarize our current knowledge of BMP-mediated osteogenesis, with a focus on BMP9, by presenting recently completed work which may help us to further elucidate these pathways.

The role of microRNAs in self-renewal and differentiation of mesenchymal stem cells

Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self-renewal and multi-lineage differentiation into mesoderm-type of cells, e.g., to osteoblasts, adipocytes, chondrocytes and possibly other cell types including hepatocytes and astrocytes. Due to their ease of culture and multipotentiality, hMSC are increasingly employed as a source for cells suitable for a number of clinical applications, e.g., non-healing bone fractures and defects and also non-skeletal degenerative diseases like heart failure. Currently, the numbers of clinical trials that employ MSC are increasing. However, several biological and biotechnological challenges need to be overcome to benefit from the full potential of hMSC. In this current review, we present some of the most important and recent advances in understanding of the biology of hMSC and their current and potential use in therapy.

Distinct roles of bone morphogenetic proteins in osteogenic differentiation of mesenchymal stem cells

Histone-targeted gene transfer of bone morphogenetic protein-2 enhances mesenchymal stem cell chondrogenic differentiation

Historical Perspectives and Advances in Mesenchymal Stem Cell Research for the Treatment of Liver Diseases

BMP9 and COX-2 form an important regulatory loop in BMP9-induced osteogenic differentiation of mesenchymal stem cells

The aim of this study was to comparatively evaluate the effects of bone morphogenetic protein-2 and the flavonoid icariin upon cardiomyocyte differentiation of bone marrow-derived mesenchymal stem cells and to investigate the mechanism(s) underlying these effects. Rat bone marrow-derived mesenchymal stem cells were isolated by fluorescence-activated cell sorting. After treatment under four experimental conditions (i.e., control, bone morphogenetic protein-2, icariin, and bone morphogenetic protein-2 + icariin), the combination of bone morphogenetic protein-2 and icariin was superior to either bone morphogenetic protein-2 or icariin monotherapy in inducing cardiomyocyte differentiation as evidenced by upregulated GATA-4, NKX2-5, cTnT, and CX-43 expression (p < 0.05). Second, the combination of bone morphogenetic protein-2 and icariin was superior to either bone morphogenetic protein-2 or icariin monotherapy in enhancing intracellular reactive oxygen species generation via synergistically promoting NADPH oxidase 4 upregulation (p < 0.05). Third, the combination of bone morphogenetic protein-2 and icariin was superior to either bone morphogenetic protein-2 or icariin monotherapy in enhancing NADPH oxidase 4-dependent, reactive oxygen species-driven p38MAPK activation (p < 0.05). Fourth, the combination of bone morphogenetic protein-2 and icariin was superior to either bone morphogenetic protein-2 or icariin monotherapy in enhancing p38MAPK-mediated bone marrow-derived mesenchymal stem cell-to-cardiomyocyte differentiation (p < 0.05). In conclusion, bone morphogenetic protein-2 and icariin combination therapy synergistically promotes p38MAPK-mediated bone marrow-derived mesenchymal stem cell-to-cardiomyocyte differentiation via enhanced NADPH oxidase 4-dependent intracellular reactive oxygen species generation. These findings provide novel insights into the NADPH oxidase 4–reactive oxygen species–p38MAPK axis-based mechanisms underlying the differentiation of bone marrow-derived mesenchymal stem cells into cardiomyocytes, which can aid in the development of superior methods for in vitro bone marrow-derived mesenchymal stem cell-to-cardiomyocyte differentiation.

Mesenchymal stem cells (MSCs) may be easily isolated from the bone marrow, and possess multi-lineage differentiation potential and various therapeutic applications. The differentiation of MSCs into osteoblasts is a complex process that is regulated by multiple internal and external factors. In the present study, the differentiation of MSCs isolated from rabbit bone marrow into osteoblasts using different osteoblast inductive media in the presence of dexamethasone, bone morphogenetic protein 2 (BMP-2), 1,25-dihydroxyvitamin D3, transforming growth factor β (TGFβ), platelet lysate and cyclooxygenase 2 (COX2), respectively. Alkaline phosphatase (ALP) activity, mineralization, collagen type (Ct) I and osteocalcin activities, and the mRNA and protein expression levels of vascular endothelial growth factor (VEGF), BMP-2 and Ct II were measured during the differentiation process in MSCs treated with different inducers. Rabbit MSCs were successfully isolated and were observed to be predominantly circular in shape after culture for 24 h. Following subculture for 5 days, the cells demonstrated a spindle shape. ALP, Ct I and osteocalcin activities were higher in cells cultured in dexamethasone, BMP-2 and TGFβ compared with the activities in control cells. Following differentiation, the dexamethasone, BMP-2 and TGFβ groups demonstrated significantly enhanced mineralization of MSCs detected by Alizarin Red S staining. The mRNA and protein expression levels of VEGF, BMP-2 and Ct II were significantly increased in the same groups compared with the levels in the control group. In conclusion, rabbit MSCs were successfully isolated from bone marrow and differentiated into osteoblasts indicated by raised ALP, Ct I and osteocalcin activities, mineralization and expression of osteogenesis-inducing genes and proteins. The present study revealed that dexamethasone, BMP-2 and TGFβ have a positive effect on cell differentiation.

Transcriptomic landscape regulated by the 14 types of bone morphogenetic proteins (BMPs) in lineage commitment and differentiation of mesenchymal stem cells (MSCs)

Inhibition of BMP signaling with LDN 193189 can influence bone marrow stromal cell fate but does not prevent hypertrophy during chondrogenesis.

Stromal derived factor-1 regulates bone morphogenetic protein 2-induced osteogenic differentiation of primary mesenchymal stem cells

Bone Morphogenetic Protein 9 Regulates Early Lymphatic-Specified Endothelial Cell Expansion during Mouse Embryonic Stem Cell Differentiation.

Bone morphogenetic protein 2 (BMP2), a member of the transforming growth factor-β (TGF-β) super-family, is one of the main chondrogenic growth factors involved in cartilage regeneration. BMP2 is known to induce chondrogenic differentiation in various types of stem cells in vitro. However, BMP2 also induces osteogenic differentiation and endochondral ossification in mesenchymal stem cells (MSCs). Although information regarding BMP2-induced chondrogenic and osteogenic differentiation within the same system might be essential for cartilage tissue engineering, few studies concerning these issues have been conducted. In this study, BMP2 was identified as a regulator of chondrogenic differentiation, osteogenic differentiation and endochondral bone formation within the same system. BMP2 was used to regulate chondrogenic and osteogenic differentiation in stem cells within the same culture system in vitro and in vivo. Any changes in the differentiation markers were assessed. BMP2 was found to induce chondrogenesis and osteogenesis in vitro via the expression of Sox9, Runx2 and its downstream markers. According to the results of the subcutaneous stem cell implantation studies, BMP2 not only induced cartilage formation but also promoted endochondral ossification during ectopic bone/cartilage formation. In fetal limb cultures, BMP2 promoted chondrocyte hypertrophy and endochondral ossification. Our data reveal that BMP2 can spontaneously induce chondrogenic differentiation, osteogenic differentiation and endochondral bone formation within the same system. Thus, BMP2 can be used in cartilage tissue engineering to regulate cartilage formation but has to be properly regulated for cartilage tissue engineering in order to retain the cartilage phenotype.

Coordinated time-dependent modulation of AMPK/Akt/mTOR signaling and autophagy controls osteogenic differentiation of human mesenchymal stem cells