THE PROTECTIVE EFFECT OF TGF-β1 TREATMENT ON MESENCHYMAL STEM CELLS INJURY CAUSED BY ANALOGOUS ISCHEMIA IN VITRO

Objective To investigate the protective effect of TGF-β1 on mesenchymal stem cells(MSCs) injury caused by analogous ischemia in vitro. Methods Density gradient centrifugalization(DGC) combined with adherence method were used to segregate and cultivate rat MSCs.MSCs cultivated to the 3 rd passage were characterized using flow cytometry technique.TGF-β1 with 1,2 and 5 μg/L were pretreated on MSCs for 8 h,then serum and oxygen deprivation were used to cause analogous ischemia of MSCs in vitro.AnnexinV/PI flow cytometry technique was used to evaluate apoptosis and survival of MSCs.Western blot technique was used to detect the expression of Akt and p-Akt when 2 μg/L TGF-β1 was pretreated on MSCs. Results DGC combined with adherence method could segregate and purify rat MSCs effectively.The results of flow cytometry showed that CD29 expression was positive while CD34 expression negative for MSCs.The results of AnnexinV/PI flow cytometry showed the number of apoptosis cell of 2 μg/L TGF-β1 pretreating on MSCs was significantly less than that of MSCs after 6 h serum and oxygen deprivation.Western blot technique showed that the ratio of p-Akt to Akt increased after pretreated by 2 μg/L TGF-β1,p-Akt /Akt at 8 h was obviously higher than that of those at other times(P0.05). Conclusion TGF-β1 treatment on MSCs could antagonize MSCs apoptosis caused by analogous ischemia in vitro by activating the signal pathway of PI3K/Akt.