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.

中文翻译：

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由于 CCNA2 基因的过表达，Muse 细胞比脂肪干细胞具有更高的应激耐受性

本研究旨在探讨多向分化应激耐受(Muse)细胞的应激耐受机制，阐明提高间充质干细胞应激耐受的途径。采用 3-( 4,5-_二甲基噻唑_-2-基)-2,5-二苯基溴化四唑还原法、流式细胞仪结合分别为 Annexin V-FITC/PI 染色和蛋白质印迹分析。观察到 Muse 细胞内的CCNA2基因水平相对于脂肪干细胞 (ASC)显着增加。在 H ₂ O ₂在体外应激环境下，与ASCs的存活率相比，Muse细胞的存活率显着提高。此外，记录了 Muse 细胞相对于 ASC 的凋亡和衰老相关蛋白表达水平降低。通过体外荧光素酶测定证实了miR-29b-3p诱导的CCNA2基因表达的负调节。转染antagomir-29b-3p的ASCs中CCNA2基因表达显着上调，提高了ASCs在H ₂ O ₂胁迫下的存活率，但显着降低了衰老相关基因的凋亡和表达；agomir-29b-3p 可以部分逆转这些影响。总之，CCNA2的高表达基因与 Muse 细胞的应激耐受性增加有关。通过miR-29b-3p调节CCNA2的表达可以改变 ASCs 的应激耐受性。