Simultaneous Osteogenesis Research Articles

Construction of oxidized icariin functionalized collagen composite with promoting osteogenesis, vascularization and anti-inflammatory properties potential for bone repair application

Bone defects are mainly treated by transplanting bone scaffold, and lack of osteogenesis, vascularization and anti-inflammatory properties will reduce the ability of new bone tissue to grow into them, thus increasing the risk of bone repair failure. In this study, inspired by the composition of natural bone, COL-BG-MOF composite was first prepared (collagen (COL) as the organic component, aminated mesoporous bioactive glass (BG-NH2) as the inorganic non-metallic component, and mesoporous silica shell-coated Mg-MOF-74 (Mg-MOF-74@MSiO2) as the metallic trace element component). Subsequently, in order to further enhance the effectiveness of its bone repair application potential, COL-BG-MOF was functionalized by oxidized Icariin (OICA) as a “growth factor” component to endow it with simultaneous osteogenesis promoting, vascularization promoting, and anti-inflammatory properties. Notably, the –CHO of OICA can react with the –NH2 in COL-BG-MOF by Schiff base reaction, which can cross-link the COL, thus improving the interfacial binding of BG-NH2 to the COL and slowing down the release rate of OICA. The results showed that the obtained functionalized composite scaffold exhibited better compressive strength, anti-degradation and osteoconductivity, as well as sustained OICA release behavior. More importantly, the synergistic effect of OICA and Mg-MOF-74@MSiO2 greatly promoted its osteogenic differentiation, HUVEC migration and anti-inflammatory properties. Therefore, this study provided a strategy to prepare functionalized composites by using modified Chinese medicine, which has great application potential in the field of bone regeneration.

Dual-Cross-Linked Magnetic Hydrogel with Programmed Release of Parathyroid Hormone Promotes Bone Healing.

Intermittent delivery of parathyroid hormone (PTH) could effectively promote bone regeneration, but the need for daily injection administration has limited its further clinical applications. Exposure to magnetic stimulation could regulate cell fate to promote osteogenesis. Herein, we developed a magnetized hydrogel with programmed PTH release and simultaneous magnetic actuation to promote osteogenic commitment. Ag dual-cross-linked hydrogel was formulated as GelMA-PVA (GP) biphasic reservoir with magnetic nanoparticles (GPM) and PTH (GPMP). Macroscopic and microscopic characterizations were performed to optimize the formulations. In vitro release assessment confirmed the programmable release of PTH with a pulsatile profile primed via magnetization in the first 4 days and a sustained release, controlled by an optimized GP matrix, for over a month. Stimulated by an alternating magnetic field, the hydrogels displayed a zigzag-shaped pulsatile release profile, and the cumulative release was enhanced by 8, 28, and 18% in In40, Ab40, and In20Ab20 (loading 40 μg PTH via incorporation, absorption, and their combination) formulations, respectively, compared with the same formulations without magnetic stimulation. An in vitro cytocompatibility test showed that all formulations were biocompatible and that PTH addition significantly promoted the proliferation of MC3T3-E1 pre-osteoblasts. In vivo studies presented enhanced new bone regeneration with significantly improved bone volume and bone mineral density in GPM and GPMP groups (increased by 120 and 251% compared with those of non-treated control), confirming their osteogenic effects and accelerated bone healing. This newly developed GPMP sample provides simultaneous osteogenesis effects via the programmed release of PTH and magnetically promoted bone regeneration and is promising in the facilitation of bone healing and treatment of various delayed/non-union conditions without the burden of daily injection.

PLGA-collagen-ECM hybrid scaffolds functionalized with biomimetic extracellular matrices secreted by mesenchymal stem cells during stepwise osteogenesis-co-adipogenesis.

A shift in osteogenesis toward adipogenesis of human bone marrow-derived mesenchymal stem cells (hMSCs) is a crucial pathological factor in the progression of osteoporosis. The development of an in vitro three-dimensional (3D) model that reflects the dynamic remodeling of extracellular matrices (ECMs) during simultaneous osteogenesis and adipogenesis of hMSCs can provide a useful tool to mimic the process and to investigate how 3D ECMs balance the osteogenic and adipogenic differentiation of hMSCs. In this study, ECMs secreted by hMSCs during their stepwise osteogenesis-co-adipogenesis were deposited on hybrid meshes of poly(lactide-co-glycolide) (PLGA) and collagen to prepare biomimetic PLGA-collagen-ECM hybrid scaffolds. Four types of stepwise differentiation ECMs were prepared: ECMs secreted by hMSCs at early stages of osteogenesis and adipogenesis (EOEA-ECMs), hMSCs at early stages of osteogenesis and late stages of adipogenesis (EOLA-ECMs), hMSCs at late stages of osteogenesis and early stages of adipogenesis (LOEA-ECMs) and hMSCs at late stages of osteogenesis and late stages of adipogenesis (LOLA-ECMs). The deposited ECMs had different compositions that were dependent on the different stages of osteogenesis and adipogenesis. They also showed different effects on balancing the adipogenic and osteogenic differentiation of hMSCs. The EOEA-ECM scaffold had a promotive effect on adipogenesis and a suppressive effect on the osteogenesis of hMSCs. The LOEA-ECM and LOLA-ECM scaffolds showed a promotive effect on osteogenesis and a moderate effect on the adipogenic differentiation of hMSCs. The EOLA-ECM scaffold exhibited a suppressive effect on both osteogenesis and adipogenesis of hMSCs. However, the EOLA-ECM scaffold promoted hMSC proliferation more strongly than the other ECM scaffolds. The results indicated that dynamically remodeling ECM scaffolds could affect the osteogenic and adipogenic differentiation of hMSCs and should provide a useful 3D cell culture model for the investigation of ECM-cell interactions.

Matrices secreted during simultaneous osteogenesis and adipogenesis of mesenchymal stem cells affect stem cells differentiation

The extracellular matrix (ECM) plays a pivotal role in regulating stem cell functions. The ECM dynamically changes during tissue development. It remains a great challenge to mimic the dynamically changing ECM. In this study, we prepared novel types of extracellular matrices that could mimic the dynamic variation of extracellular matrices, which were derived from simultaneous osteogenesis and adipogenesis of human bone marrow-derived mesenchymal stem cells (MSCs). Four ECMs simultaneously mimicking early osteogenesis and early adipogenesis (EOEA), early osteogenesis and late adipogenesis (EOLA), late osteogenesis and early adipogenesis (LOEA), late osteogenesis and late adipogenesis (LOLA) were prepared. The stepwise osteogenesis–co-adipogenesis-mimicking matrices had different compositions and different effects on the osteogenic and adipogenic differentiation of MSCs. The matrices could provide very useful tools to investigate the interaction between ECM and stem cells and the role of ECM on stem cell differentiation. Statement of SignificanceExtracellular matrices (ECMs) are dynamically remodeled to regulate stem cell functions during tissue development. Until now, mimicking the ECM variation during stem cell differentiation to single cell type has been reported. However, there is no report on simultaneous mimicking of stem cell differentiation to two types of cells. In this study, we prepared the mixture ECMs derived from simultaneous osteogenesis and adipogenesis of MSCs at different stages and found that they could regulate stem cell differentiation. The concept is new and the ECMs are novel. No such ECMs have been reported previously. The matrices will provide very useful tools to investigate the interaction between ECM and stem cells and the role of ECM on stem cell differentiation.

Tissue development-mimicking extracellular matrices from cultured cells

Event Abstract Back to Event Tissue development-mimicking extracellular matrices from cultured cells Guoping Chen1, 2, Rong Cai1, 2, Takashi Hoshiba3 and Naoki Kawazoe1 1 National Institute for Materials Science, Tissue Regeneration Materials Unit, International Center for Materials Nanoarchitectonics, Japan 2 University of Tsukuba, Department of Materials Science and Engineering, Graduate School of Pure and Applied Sciences, Japan 3 Yamagata University, Department of Biochemical Engineering, Graduate School of Science and Engineering, Japan Introduction: Extracellular matrix (ECM) provides various signals for manipulating cell functions and maintaining the homeostasis of living organisms. ECM is tissue-specific and dynamically remodelled during the development and aging process. We have established a method to prepare development-mimicking ECM by using cultured cells. By the method, we have prepared “stepwise osteogenesis-mimicking matrices” and “stepwise adipogenesis-mimicking matrices” that respectively replicated the dynamically changing ECM secreted at different stages of osteogenesis or adipogenesis[1]-[3]. Although these ECM models can mimic ECM changes during osteogenesis and adipogenesis separately, they cannot simultaneously mimic osteogenesis and adipogenesis to make their complex ECM. Therefore, in this study, ECM mimicking the simultaneous osteogenesis and adipogenesis of MSCs were prepared. Materials and Methods: Human bone marrow-derived mesenchymal stem cells (MSCs) were seeded on tissue culture polystyrene (TCPS) plates at a density of 5,000 cells/cm2. To induce cells undergoing simultaneous osteogenesis and adipogenesis, MSCs were cultured in mixture media composed of osteogenic medium (OM) and adipogenic medium (AM) at OM/AM ratio of 95/5 (O95A5), 85/15 (O85A15), 70/30 (O70A30) and 50/50 (O50A50). The cells were cultured for 7, 14 and 21 days. The different differentiation stages of MSCs were confirmed by histological staining (alkaline phosphatase and Alizarin red S) and analysis of differentiation process related genes encoding ALP, IBSP and LPL. The cells at different stages of osteogenesis-co-adipogenesis were decellularized to prepare their respective matrices. The main components in the matrices were analysed by immunocytochemical staining of type I collagen, biglycan, fibronectin, decorin, laminin α-4 and versican. Results and Discussion: The progress of simultaneous osteogenic and adipogenic differentiation of MSCs was confirmed by histological staining and related gene expression. The results indicated that MSCs cultured in mixture media showed simultaneous osteogenesis and adipogenesis at different stages. MSCs cultured in O85A15 for 1 week showed early osteogenesis and early adipogenesis (EOEA). MSCs cultured in O50A50 for 2 weeks showed early osteogenesis and late adipogenesis (EOLA) stage. MSCs cultured in O95A5 for 3 weeks were at a stage of late osteogenesis and early adipogenesis (LOEA). MSCs cultured in O70A30 for 3 weeks were at a stage of late osteogenesis and late adipogenesis (LOLA). MSCs cultured in basal medium for 1 week were defined as cells at the undifferentiated stem cell stage (SC). Five different simultaneous osteogenesis- and adipogenesis-mimicking matrices (OEAE, OLAE, OEAL, OLAL and SC) were prepared after decellularization. Immunocytochemical staining showed that the composition of the matrices changed depending on the stepwise stage of osteogenic and adipogenic differentiation. Conclusion: Five types of ECM that mimicked the dynamically changing ECM during simultaneous osteogenesis and adipogenesis of MSCs were prepared by culturing MSCs in mixture media of osteogenic medium and adipogenic medium for different culture period. The stepwise osteogenesis-co-adipogenesis-mimicking ECM had different composition depending on the stage of osteogenesis-co-adipogenesis. This study was supported by World Premier International Research Center Initiative on Materials Nanoarchitectonics and KAKENHI Grant Number 15H03027 from the Ministry of Education, Culture, Sports, Science and Technology, Japan.

Control of Simultaneous Osteogenic and Adipogenic Differentiation of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are pluripotent cells which can differentiate into several distinct lineages such as osteoblasts and adipocytes. Osteogenesis and adipogenesis of MSCs induced with specific induction factors have been well exploited. However, it is not clear how simultaneous osteogenesis and adipogenesis of MSCs is balanced by the composition of induction medium. In this study, MSCs were cultured in the mixture medium at different ratio of osteogenic medium (OM) and adipogenic medium (AM) to investigate the simultaneous osteogenesis and adipogenesis of MSCs. Differentiation was investigated by histological staining and real-time PCR analysis. The results showed that adipogenesis was dosage dependent on the concentration of adipogenic induction factors, while osteogenesis was not. The balance of osteogenesis and adipogenesis could be control by different ratio of osteogenic and adipogenic media. The results will be useful for controlling stem cell differentiation.