载有 FTY720 的神经干细胞衍生的外泌体通过 PTEN/AKT 信号通路促进大鼠脊髓损伤后的恢复。

Exosomes Derived from Nerve Stem Cells Loaded with FTY720 Promote the Recovery after Spinal Cord Injury in Rats by PTEN/AKT Signal Pathway.

机构信息

Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.

Department of Biomedical Engineering, College of Biology, Hunan University, Changsha 410082, China.

出版信息

J Immunol Res. 2021 Jul 14;2021:8100298. doi: 10.1155/2021/8100298. eCollection 2021.

BACKGROUND

Spinal cord injury (SCI) remains a challenge owing to limited therapies. The exosome of neural stem cells (NSCs-Exos) and FTY720 transplantation could improve SCI effectively. However, the effect and mechanism of NSCs-Exos combined with FTY720 (FTY720-NSCs-Exos) transplantation in the treatment of SCI are not fully understood.

METHODS

Sprague Dawley rats (8-week-old) were used to establish the SCI model, followed by the treatment of NSCs-Exos, FTY720, and FTY720-NSCs-Exos. The effect of FTY720, NSCs-Exos, and FTY720-NSCs-Exos combination treatment on hindlimb function, pathological changes, apoptosis activity, and the expression of spinal edema-related proteins and apoptosis-related proteins in SCI models were investigated by BBB scoring, HE staining, TUNEL staining and immunohistochemistry, and Western blotting. Meanwhile, the effect of these treatments on spinal cord microvascular endothelial cells (SCMECs) was detected under hypoxic circumstance.

RESULTS

Our results found that FTY720-NSCs-Exos could alleviate pathological alterations and ameliorate the hindlimb function and oxygen insufficiency in model mice after SCI. In addition, exosomes could ameliorate the morphology of neurons, reduce inflammatory infiltration and edema, decrease the expression of Bax and AQP-4, upregulate the expression of claudin-5 and Bcl-2, and inhibit cell apoptosis. At the same time, experiments showed that FTY720-NSCs-Exos could protect the barrier of SCMECs under hypoxic circumstance, and the mechanism is related to PTEN/AKT pathway.

CONCLUSION

FTY720-NSCs-Exos therapy displayed a positive therapeutic effect on SCI by regulating PTEN/AKT pathway and offered a new therapy for SCI.

背景

脊髓损伤（SCI）仍然是一个挑战，因为治疗方法有限。神经干细胞（NSCs-Exos）外泌体和 FTY720 移植可以有效地改善 SCI。然而，NSCs-Exos 联合 FTY720（FTY720-NSCs-Exos）移植治疗 SCI 的效果和机制尚不完全清楚。

方法

使用 8 周龄 Sprague Dawley 大鼠建立 SCI 模型，随后进行 NSCs-Exos、FTY720 和 FTY720-NSCs-Exos 治疗。通过 BBB 评分、HE 染色、TUNEL 染色和免疫组织化学以及 Western blot 检测 FTY720、NSCs-Exos 和 FTY720-NSCs-Exos 联合治疗对 SCI 模型后后肢功能、病理变化、细胞凋亡活性以及与脊髓水肿相关蛋白和凋亡相关蛋白表达的影响。同时，在缺氧环境下检测这些治疗方法对脊髓微血管内皮细胞（SCMECs）的影响。

结果

结果发现，FTY720-NSCs-Exos 可减轻病理改变，改善 SCI 后模型小鼠后肢功能和缺氧。此外，外泌体可以改善神经元形态，减少炎症浸润和水肿，降低 Bax 和 AQP-4 的表达，上调 claudin-5 和 Bcl-2 的表达，抑制细胞凋亡。同时，实验表明 FTY720-NSCs-Exos 可以在缺氧环境下保护 SCMECs 的屏障，其机制与 PTEN/AKT 通路有关。