Mesenchymal stem cells (MSCs) have restricted life spans in vitro and can therefore only be expanded for a limited number of cell divisions before entering a senescent state and unequivocally stopping proliferation. Several types of cell culture systems have been used for large-scale expansion of MSCs. A recent trend in cell culture has been the change from serum-use to serum-supplement media. This study was conducted to investigate the proliferative effects of vegetable resources (VR) on equine adipose tissue-derived mesenchymal stem cells (eAD-MSCs) in the absence of serum and their possible mechanisms of action. Regulation of cell cycling is a key process involved in the fate of stem cells, including renewal and differentiation. In this study, we observed that the viability of eAD-MSCs was increased significantly when treated with VR under serum-free conditions. We also observed that expression levels of cell cycling-related proteins such as p53 and p21 were decreased, and proliferating cell nuclear antigen increased significantly in response to treatment with VR in eAD-MSCs under serum-free conditions. Furthermore, expression levels of cell survival-related proteins were increased in response to treatment with VR in eAD-MSCs under serum-free conditions. Therefore, our results suggest that VR promotes proliferation of eAD-MSCs under serum-free conditions.

Mesenchymal stem cells (MSCs) are primary candidates for cell therapy and tissue engineering applications. A two-dimensional (2D) culture system is typically used for cell growth, but that method affects the characteristics of stem cells. The physiological cell environment connects cells not only to each other, but also to the extracellular matrix providing mechanical support, exposing the entire cell surface, and opening signaling pathways. The hanging drop method is the most widely used 3D culture method for spheroid formation. In this study, we investigated the relationship between spheroid size and changes in gene expression to determine the optimum spheroid size for use in tissue engineering. The expression levels of stemness factors such as NANOG, OCT4, and SOX2, angiogenic factors such as VEGF and IL-8, and osteogenic factors such as COX2 and TGF-β1 increased with spheroid size in the respective spheroid formation groups unlike the responses in their monolayer groups. Therefore, our results indicate that spheroid formation through the hanging drop method can increase the efficiency of MSCs-based tissue engineering over that obtained via traditional 2D cell culture systems.

Bone fractures are most often seen in racetrack horses because of the high level of intensity in racing. These issues are the main cause of decreased performance in racehorses. Mesenchymal stem cells (MSCs) have been explored to improve intra-articular therapy in racehorses. MSCs are essential for the repair and regeneration of damaged tissues. In this study, the effect of intra-articular injection of MSCs in racehorses was investigated. Before accessing the MSC therapy, synovial fluids were obtained from the fracture site of racehorses, and adipose tissue was collected for MSC isolation. Using the MSC specific marker, adipose tissue-derived MSCs were identified. The racehorses received intra-articular injection of autologous MSCs (or allogeneic) (3 × 107 cells/3 mL). After 1 or 2 weeks, synovial fluids were collected from racehorses. To test the effect of MSC injection using ELISA, we analyzed inflammatory factors from the untreated samples compared to MSC-treated samples of racehorses. The level of pro-inflammatory factors (interleukin-1β and prostaglandin E2) was significantly decreased in synovial fluids of MSC-injected racehorses, compared to before accessing the MSC therapy, whereas, the level of anti-inflammatory factor (interleukin-10) was higher than prior to accessing the MSC therapy. Further studies are needed to investigate the anti-inflammatory mechanism of MSC in racehorses.