Long-Term Trypsin Treatment Promotes Stem Cell Potency of Canine Adipose-Derived Mesenchymal Stem Cells

Multilineage-Differentiating Stress-Enduring Cells (Muse Cells): The Future of Human and Veterinary Regenerative Medicine

In recent years, several studies have been conducted on Muse cells mainly due to their pluripotency, high tolerance to stress, self-renewal capacity, ability to repair DNA damage and not being tumoral. Additionally, since these stem cells can be isolated from different tissues in the adult organism, obtaining them is not considered an ethical problem, providing an advantage over embryonic stem cells. Regarding their therapeutic potential, few studies have reported clinical applications in the treatment of different diseases, such as aortic aneurysm and chondral injuries in the mouse or acute myocardial infarction in the swine, rabbit, sheep and in humans. This review aims to describe the characterization of Muse cells, show their biological characteristics, explain the differences between Muse cells and mesenchymal stem cells, and present their contribution to the treatment of some diseases.

Muse Cells Have Higher Stress Tolerance than Adipose Stem Cells due to the Overexpression of the CCNA2 Gene

This study aimed to investigate the stress tolerance mechanism of multilineage-differentiating stress enduring (Muse) cells and elucidate the means to improve the stress tolerance of mesenchymal stem cells. Cell viability, apoptosis, and senescence-related protein expression were detected under H₂O₂ stress by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium reduction assay, flow cytometry in combination with Annexin V-FITC/PI staining, and western blotting analysis, respectively. A significant increase in the CCNA2 gene level within Muse cells relative to adipose stem cells (ASCs) was observed. In the H₂O₂ stress environment in vitro, the survival rate of Muse cells remarkably increased compared with the survival rate of the ASCs. In addition, a reduced level of apoptosis and senescence-related protein expression of Muse cells relative to ASCs was documented. The miR-29b-3p-induced negative regulation of CCNA2 gene expression was confirmed by in vitro luciferase assay. A significant upregulation of CCNA2 gene expression in ASCs, transfected with antagomir-29b-3p, improved the survival rate of ASCs under H₂O₂ stress but dramatically reduced the apoptosis and expression of the senescence-related gene; agomir-29b-3p could partially reverse these effects. In conclusion, high expression of the CCNA2 gene is associated with an increased stress tolerance of Muse cells. Regulating the expression of CCNA2 by miR-29b-3p can alter the stress tolerance of ASCs.