Rehabilitation Medicine, Qujing No. 1 Hospital, Qujing 655000, Yunnan, China.
Rehabilitation Medicine, Shizong County People's Hospital, Shizong 655700, Yunnan, China.
Crit Rev Eukaryot Gene Expr. 2024;34(7):1-16. doi: 10.1615/CritRevEukaryotGeneExpr.2024053225.
The aim of the present study was to explore the molecular mechanisms by which miR-193b-3p-trans-fected bone marrow mesenchymal stem cells (BMSCs) transplantation improves neurological impairment after traumatic brain injury (TBI) through sphingosine-1-phosphate receptor 3 (S1PR3)-mediated regulation of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway at the cellular and animal levels. BMSCs were transfected with miR-193b-3p. A TBI cell model was established by oxygen-glucose deprivation (OGD)-induced HT22 cells, and a TBI animal model was established by controlled cortical impact (CCI). Cell apoptosis was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL), and cell activity was detected by a cell counting kit 8 (CCK-8) assay. Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression of related proteins and genes. In this study, transfection of miR-193b-3p into BMSCs significantly enhanced BMSCs proliferation and differentiation. Transfection of miR-193b-3p reduced the levels of the interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-alpha (TNF-α) inflammatory factors in cells and mouse models, and it inhibited neuronal apoptosis, which alleviated OGD-induced HT22 cell damage and neural function damage in TBI mice. Downstream experiments showed that miR-193b-3p targeting negatively regulated the expression of S1PR3, promoted the activation of the PI3K/AKT/mTOR signaling pathway, and inhibited the levels of apoptosis and inflammatory factors, which subsequently improved OGD-induced neuronal cell damage and nerve function damage in TBI mice. However, S1PR3 overexpression or inhibition of the PI3K/AKT/mTOR signaling pathway using the IN-2 inhibitor weakened the protective effect of miR-193b-3p-transfected BMSCs on HT22 cells. Transplantation of miR-193b-3p-transfected BMSCs inhibits neurological injury and improves the progression of TBI in mice through S1PR3-mediated regulation of the PI3K/AKT/mTOR pathway.
本研究旨在探讨 miR-193b-3p 转染骨髓间充质干细胞（BMSCs）通过 S1P 受体 3（S1PR3）调节磷脂酰肌醇 3-激酶/蛋白激酶 B/雷帕霉素靶蛋白（PI3K/AKT/mTOR）通路在细胞和动物水平上改善创伤性脑损伤（TBI）后神经功能缺损的分子机制。将 BMSCs 转染 miR-193b-3p。通过氧葡萄糖剥夺（OGD）诱导的 HT22 细胞建立 TBI 细胞模型，通过皮质撞击（CCI）建立 TBI 动物模型。通过末端脱氧核苷酸转移酶（TdT）介导的 dUTP 缺口末端标记（TUNEL）检测细胞凋亡，通过细胞计数试剂盒 8（CCK-8）检测细胞活性。Western blot 分析和实时定量聚合酶链反应（qRT-PCR）用于检测相关蛋白和基因的表达。在本研究中，miR-193b-3p 转染 BMSCs 显著增强了 BMSCs 的增殖和分化。miR-193b-3p 转染降低了细胞和小鼠模型中白细胞介素-6（IL-6）、白细胞介素-1β（IL-1β）和肿瘤坏死因子-α（TNF-α）炎症因子的水平，抑制了神经元凋亡，减轻了 OGD 诱导的 HT22 细胞损伤和 TBI 小鼠的神经功能损伤。后续实验表明，miR-193b-3p 靶向负调控 S1PR3 的表达，促进 PI3K/AKT/mTOR 信号通路的激活，抑制凋亡和炎症因子水平，从而改善 OGD 诱导的 TBI 小鼠神经元细胞损伤和神经功能损伤。然而，S1PR3 过表达或使用 IN-2 抑制剂抑制 PI3K/AKT/mTOR 信号通路削弱了 miR-193b-3p 转染 BMSCs 对 HT22 细胞的保护作用。转染 miR-193b-3p 的 BMSCs 通过 S1PR3 介导的 PI3K/AKT/mTOR 通路调节抑制神经损伤，改善 TBI 小鼠的进展。
