鞘氨醇-1-磷酸对人脐带间充质干细胞增殖及表面标记物表达的影响

鞘氨醇－1－磷酸（sphingosine－1 phosphate, S1P）是一种脂质信号分子，与细胞增殖、凋亡和迁移等有密切关系．本研究发现,S1P促进人脐带间充质干细胞(human umbilical cord mesenchymal stem cells, hUC－MSCs)增殖，但目前关于其作用信号通路及S1P对hUC－MSCs表面标记表达的影响尚不十分清楚．Real－time PCR检测hUC－MSCs中S1P受体mRNA表达情况，发现在hUC－MSCs中优势表达S1PR1 3，而S1PR4、S1PR5的表达很少．MTT法检测S1PR1/3拮抗剂VPC23019、S1PR2拮抗剂JTE013、S1PR3拮抗剂CAY10444、Gi蛋白抑制剂PTX和ERK抑制剂PD98059对S1P诱导hUC－MSCs增殖的影响．结果显示，VPC23019完全抑制S1P诱导的hUC MSCs增殖，JTE013对此没有明显影响，CAY10444部分抑制S1P诱导的hUC MSCs增殖，PTX、PD98059完全抑制S1P诱导hUC－MSCs增殖．进一步用Western印迹检测ERK1/2磷酸化水平揭示,S1P通过促进ERK1/2磷酸化进而促进hUC MSCs增殖．流式细胞术检测发现,S1P对hUC MSCs表面标记物(CD45、CD34、CD90、CD29、CD105、CD44、CD73、CD71)表达没有明显影响．本研究证明，S1P通过S1PR1/3、Gi偶联蛋白及ERK1/2信号通路促进hUC MSCs增殖，而对hUC MSCs表面标记物表达无明显影响．

Effects of Sphingosine-1-phosphate on Proliferation and Cell-surface Markers of Human Umbilical Cord Mesenchymal Stem Cells

Sphingosine-1-phosphate(S1P) is a bioactive phospholipid molecule with multiple biological functions,such as cell proliferation,apoptosis,migration.In the present study,we found that S1P stimulated proliferation of human umbilical cord mesenchymal stem cells(hUC-MSCs).In order to clarify the signaling pathway of hUC-MSCs proliferation in response to S1P and it’s effect on cell-surface markers of hUC-MSCs,we detected the level of the S1P receptors(S1PRs) mRNA by real-time PCR.MTT assay was used to measure the effects of VPC23019(S1P1/3 receptor antagonist),JTE013(S1P2 receptor antagonist),CAY10444(S1P3 receptor antagonist),PTX(Gi inhibitor) and PD98059(ERK inhibitor) on proliferation of hUC-MSCs induced by S1P.Then we checked the level of p-ERK by Western blotting.Flow cytometry was used to detect the cell-surface markers.The results showed that S1P stimulates hUC-MSCs proliferation in a dose dependent manner.S1PR1-3 mRNA was mainly expressed in hUC-MSCs and S1PR4,S1PR5 levels were low.VPC23019 completely and CAY10444 partly inhibited S1P-induced hUC-MSCs proliferation,but JTE013 had no significant effects.PTX and PD98059 inhibited S1P-induced hUC-MSCs proliferation and ERK1/2 phosphorylation.In conclusion,S1P stimulated the proliferation of hUC-MSCs through S1PR1/3,Gi and ERK1/2 signal pathway,but no effect was observed on the cell-surface markers of hUC-MSCs.