Postoperative cognitive dysfunction (POCD) is a severe complication of cardiopulmonary bypass (CPB) and has common characteristics such as acute cognitive dysfunction, impaired memory, and inattention. Mesenchymal stem cells (MSCs) are multipotent cells that have therapeutic potentials mainly through paracrine action via secreting growth factors and cytokines. Exosomes are one of the important paracrine factors and have been reported as potential cell-free therapy for the treatment of autoimmune and central nervous system disorders. In this study, we examined exosomes derived from antler MSCs (AMSCs) of POCD rats after CPB and evaluated their potential regulatory mechanisms. AMSC-derived exosomes reduced neurological damage and brain damage and prevent apoptosis in CPB rats. Furthermore, AMSC-derived exosomes were found to reduce hippocampal neuronal apoptosis and the expression of TLR2, TLR4, MyD88, and NF-κB in CPB rats. However, the above effects of AMSC-derived exosomes on CPB rats were abolished partially by toll-like receptor 2/4 (TLR2/TLR4) agonist (LPS-EB). In conclusion, AMSC-derived exosomes can improve cognitive function in CPB rats through inhibiting the TLR2/TLR4 signaling pathway.

中文翻译：

---

鹿茸间充质干细胞外泌体通过抑制TLR2 / TLR4信号通路改善心肺旁路大鼠的术后认知功能障碍。

术后认知功能障碍（POCD）是一种严重的体外循环（CPB）并发症，具有一些共同的特征，例如急性认知功能障碍，记忆力减退和注意力不集中。间充质干细胞（MSCs）是多能干细胞，主要通过分泌分泌生长因子和细胞因子的旁分泌作用而具有治疗潜力。外来体是重要的旁分泌因子之一，据报道是潜在的无细胞疗法，可用于治疗自身免疫和中枢神经系统疾病。在这项研究中，我们检查了CPB后POCD大鼠的鹿角MSC（AMSC）衍生的外泌体，并评估了其潜在的调控机制。AMSC衍生的外泌体减少了CPB大鼠的神经损伤和脑损伤，并防止了其凋亡。此外，CPB大鼠中的κB。但是，由Toll样受体2/4（TLR2 / TLR4）激动剂（LPS-EB）消除了AMSC衍生的外来体对CPB大鼠的上述作用。总之，AMSC衍生的外来体可通过抑制TLR2 / TLR4信号通路改善CPB大鼠的认知功能。