Liu Huiying, Zhang Zili, Li Puyuan, Yuan Xin, Zheng Jing, Liu Jinwen, Bai Changqing, Niu Wenkai
Department of Respiratory and Critical Care Diseases, 307th Hospital of PLA , Beijing , The People's Republic of China.
Beijing Oriental Yamei Gene Science & Technology Institute , Beijing , The People's Republic of China.
PeerJ. 2016 Dec 13;4:e2712. doi: 10.7717/peerj.2712. eCollection 2016.
Acute lung injury and acute respiratory distress syndrome (ALI/ARDS) is a severe clinical syndrome with mortality rate as high as 30-40%. There is no treatment yet to improve pulmonary endothelial barrier function in patients with severe pulmonary edema. Developing therapies to protect endothelial barrier integrity and stabilizing gas exchange is getting more and more attention. Sphingosine-1-phosphate (S1P) is able to enhance the resistance of endothelial cell barrier. S1P at physiological concentrations plays an important role in maintaining endothelial barrier function. Proliferation, regeneration and anti-inflammatory activity that mesenchymal stem cells (MSCs) exhibit make it possible to regulate the homeostatic control of S1P.
By building a pulmonary endothelial cell model of acute injury, we investigated the regulation of S1P receptors and sphingosine kinases expression by MSCs during the treatment of acute lung injury using RT-PCR, and investigated the HPAECs Micro-electronics impedance using Real Time Cellular Analysis.
It was found that the down-regulation of TNF- expression was more significant when MSC was used in combination with S1P. The combination effection mainly worked on S1PR2, S1PR3 and SphK2. The results show that when MSCs were used in combination with S1P, the selectivity of S1P receptors was increased and the homeostatic control of S1P concentration was improved through regulation of expression of S1P metabolic enzymes.
The study found that, as a potential treatment, MSCs could work on multiple S1P related genes simultaneously. When it was used in combination with S1P, the expression regulation result of related genes was not simply the superposition of each other, but more significant outcome was obtained. This study establishes the experimental basis for further exploring the efficacy of improving endothelial barrier function in acute lung injury, using MSCs in combination with S1P and their possible synergistic mechanism.
急性肺损伤和急性呼吸窘迫综合征（ALI/ARDS）是一种严重的临床综合征，死亡率高达30%-40%。目前尚无改善重症肺水肿患者肺内皮屏障功能的治疗方法。开发保护内皮屏障完整性和稳定气体交换的疗法越来越受到关注。1-磷酸鞘氨醇（S1P）能够增强内皮细胞屏障的抵抗力。生理浓度的S1P在维持内皮屏障功能中起重要作用。间充质干细胞（MSCs）表现出的增殖、再生和抗炎活性使其有可能调节S1P的稳态控制。
通过构建急性损伤的肺内皮细胞模型，我们使用RT-PCR研究了MSCs在急性肺损伤治疗过程中对S1P受体和鞘氨醇激酶表达的调节，并使用实时细胞分析研究了人肺微血管内皮细胞（HPAECs）的微电子阻抗。
发现当MSCs与S1P联合使用时，肿瘤坏死因子（TNF）表达的下调更显著。联合作用主要作用于S1PR2、S1PR3和SphK2。结果表明，当MSCs与S1P联合使用时，S1P受体的选择性增加，并且通过调节S1P代谢酶的表达改善了S1P浓度的稳态控制。
该研究发现，作为一种潜在的治疗方法，MSCs可以同时作用于多个与S1P相关的基因。当它与S1P联合使用时，相关基因的表达调节结果并非简单的相互叠加，而是获得了更显著的效果。本研究为进一步探索使用MSCs与S1P联合改善急性肺损伤中内皮屏障功能的疗效及其可能的协同机制奠定了实验基础。
