楊大志(Yang Dazhi，Dept Orthop，Union

Hosp，Tongji Med Col，Huazhong Univ Sci Technol，Wuhan 430030)…∥Chin J Exp Surg.－2011，28(2).－288～291

Influence of bone morphogenetic proteins-2 and strontium chloride on the human umbilical cord mesenchymal stem cells proliferation and osteogenic differentaton

楊大志(Yang Dazhi，Dept Orthop，Union

Hosp，Tongji Med Col，Huazhong Univ Sci Technol，Wuhan 430030)…∥Chin J Exp Surg.－2011，28(2).－288～291

ObjectiveTo study the effects of combination of bone morphogenetic protein-2(BMP-2)and strontium chloride on proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells(hUCMSCs)in vitro culture.MethodshUCMSCs were cultured in vitro，and added with BMP-2 and strontium chloride.Accoding to the culture media used，three experimental groups were set up:blank group(10% FCS/DMEM)，control group(10%FCS/DMEM +osteogenic medium)，experimental group(10%FCS/DMEM+BMP-2+strontium chloride).Cell proliferation was measured by methylthiazol tetrazolium(MTT)method.Cell differentiation was examined by alkaline phosphatase(ALP)measurement kit.The expression levels of Osteopontin(OPN)，alkaline phosphatase(ALP)and type 1 collagen(COL1)mRNA was detected by using reverse transcription-polymerase chain reaction (RTPCR).The expression of smad1/5/8 and p38 was assayed by Western boltting.Von Kossa staining method was used to study the calcification effects.ResultsAs compared with blank group and control group，the proliferation in experiment group was significnatly promoted after culture for 5 days and 7 days(P ＜0.05).The ALP activity in experimentalgroup was increased from(33.443 ±9.061)U/g.prot at 3rd day to(80.209 ±17.011)U/g.prot at 5th day，even to(145.705 ± 45.871)U/g.prot at 14th day as compared with other groups(P ＜0.05).In experimental group，ALP，COL 1 and OPN mRNA were highly expressed.On the contrary，OPN mRNA was weakly expressed in blank group(P＜0.05).Smad1/5/8 and p38 was highly expressed in experimental group，but weakly in blank group(P ＜0.05).Many mineralized nodes were observed after culture for 28 days in the BMP-2 + strontium chloride medium.ConclusionBMP-2 in combination with strontium chloride can promote the proliferation and osteogenic differentiation of hUCMSCs.10 refs，2 tabs.

(Authors)