Utilization of canine mesenchymal stem cells (cMSCs) for regenerating incorrigible bone diseases has been introduced. However, cMSCs harvested from different sources showed distinct osteogenicity. To clarify this, comparative proteomics-based systems biology analysis was used to analyze osteogenic differentiation behavior by cMSCs harvested from bone marrow and dental pulp. The results illustrated that canine dental pulp stem cells (cDPSCs) contained superior osteogenicity comparing with canine bone marrow-derived MSCs (cBM-MSCs) regarding alkaline phosphatase activity, matrix mineralization, and osteogenic marker expression. Global analyses by proteomics platform showed distinct protein clustering and expression pattern upon an in vitro osteogenic induction between them. Database annotation using Reactome and DAVID revealed contrast and unique expression profile of osteogenesis-related proteins, particularly on signaling pathways, cellular components and processes, and cellular metabolisms. Functional assay and hierarchical clustering for tracking protein dynamic change confirmed that cBM-MSCs required the presences of Wnt, transforming growth factor (TGF)-beta, and bone-morphogenetic protein (BMP) signaling, while cDPSCs mainly relied on BMP signaling presentation during osteogenic differentiation in vitro. Therefore, these findings illustrated the comprehensive data regarding an in vitro osteogenic differentiation behavior by cBM-MSCs and cDPSCs which is crucial for further mechanism study and the establishment of cMSC-based bone tissue engineering (BTE) for veterinary practice.

The trend of regenerative therapy for diabetes in human and veterinary practices has conceptually been proven according to the Edmonton protocol and animal models. Establishing an alternative insulin-producing cell (IPC) resource for further clinical application is a challenging task. This study investigated IPC generation from two practical canine mesenchymal stem cells (cMSCs), canine bone marrow-derived MSCs (cBM-MSCs) and canine adipose-derived MSCs (cAD-MSCs). The results illustrated that cBM-MSCs and cAD-MSCs contain distinct pancreatic differentiation potential and require the tailor-made induction protocols. The effective generation of cBM-MSC-derived IPCs needs the integration of genetic and microenvironment manipulation using a hanging-drop culture of PDX1-transfected cBM-MSCs under a three-step pancreatic induction protocol. However, this protocol is resource- and time-consuming. Another study on cAD-MSC-derived IPC generation found that IPC colonies could be obtained by a low attachment culture under the three-step induction protocol. Further, Notch signaling inhibition during pancreatic endoderm/progenitor induction yielded IPC colonies through the trend of glucose-responsive C-peptide secretion. Thus, this study showed that IPCs could be obtained from cBM-MSCs and cAD-MSCs through different induction techniques. Also, further signaling manipulation studies should be conducted to maximize the protocol’s efficiency.

Bone tissue engineering has been widely studied and proposed as a promising platform for correcting the bone defects. The applications of mesenchymal stem cell (MSC)-based bone tissue engineering have been investigated in various in vitro and in vivo models. In this regard, the promising animal bone defect models have been employed for illustrating the bone regenerative capacity of MSC-based bone tissue engineering. However, most studies aimed for clinical applications in human. These evidences suggest a knowledge gap to fulfill the accomplishment for veterinary implementation. In this review, the fundamental concept, knowledge, and technology of MSC-based bone tissue engineering focusing on veterinary applications are summarized. In addition, the potential canine MSCs resources for veterinary bone tissue engineering are reviewed, including canine bone marrow-derived MSCs, canine adipose-derived MSCs, and canine dental tissue-derived MSCs. This review will provide a basic and current information for studies aiming for the utilization of MSC-based bone tissue engineering in veterinary practice.

Establishing the intervention to enhance proliferation and differentiation potential is crucial for the clinical translation of stem cell-based therapy. In this study, the effects of simvastatin on these regards were explored. Canine bone marrow-derived mesenchymal stem cells (cBM-MSCs) were treated with 4 doses of simvastatin, 0.1, 1, 10, and 100 nM. Simvastatin in low-dose range, 0.1 and 1 nM, enhanced dose-dependent cell proliferation at day 5 and 7. Exploration of the mechanisms revealed that simvastatin in low-dose range dose-dependently upregulated sets of cell cycle regulators, Cyclin D1 and Cyclin D2; proliferation marker, Ki-67; and anti-apoptotic gene; Bcl-2. Interestingly, pluripotent markers, Rex1 and Oct4, were dramatically increased upon the low-dose treatment. Contrastingly, treatment with high-dose simvastatin suppressed the expression of those genes. Thus, the results suggested beneficial effects of simvastatin on cBM-MSCs proliferation and expansion. Further study regarding differentiation potential and underlying mechanisms will accelerate the clinical application of the molecule on veterinary stem cell-based therapy.

No abstract