Effect Of Pure Titanium Suface-loaded Cyclo(RGDFK) On Proliferation And Signal Transduction Pathway Of Osteoblasts

Objective: After the formation of the ultrasonic micro-arc oxidation coating,ultrasonic micro-arc oxidation-polydopamine coating and the ultrasonic micro-arc oxidationpolydopamine-cyclopeptide c(RGDfk)biocomposite coating on the surface of pure titanium,the MC3T3-E1 osteoblasts were cultured on the three groups of coatings respectively.The proliferation of MC3T3-E1 osteoblasts on the three groups of coatings,the changes of cell viability,and the protein expression of the related signal transduction pathways were included into the observation process to examine the possible signal pathways related to the proliferation and cell activity regulation of MC3T3-E1 on the surface of pure titanium microarc oxidation-polydopamine-c(RGDfk)biocomposite coating,which will lay foundation for further researching.Methods: Ultrasonic micro-arc oxidation on pure titanium surface(control group 1)and ultrasonic micro arc oxidation-polydopamine on pure titanium surface(control group 2)were all set as control groups.ultrasonic microarc oxidation on poly-titanium surfacepolydopamine-cyclopeptide.The c(RGDfk)polypeptide was referred as an experimental group.CCK-8 method and ALP method were applyed to detect the proliferation and viability of MC3T3-E1 osteoblast lineages on the three groups of coatings and the same coating at different times.Western blot analysis was put in use to analyze the quantity and activity of the relevant proteins in the focal adhesion kinase signaling pathway and MAPK signaling pathway after MC3T3-E1 cultured in different coatings.Results: The micro-arc oxidation on the surface of pure titanium-polydopaminecyclopeptide c(RGDfk)composite coatings significantly promoted the proliferation and activity of MC3T3-E1 osteoblasts at the same time and was superior to that of the control group2,as well as better than the control group 1.With the prolongation of culture time in one week,the cell proliferation rate of microarc oxidation-polydopamine-cyclopeptide c(RGDfk)composite coating was more obvious than that of control group 1 and control group 2,as the ALP activity demonstrates better performance;after culture of the composite coating,MC3T3-E1 osteoblasts up-regulated the expression of focal adhesion kinase and related proteins on the MAPK signaling pathway,and sFAK levels were improved,but the sFAK changes in microarc oxidation-polydopamine group and micro-arc oxidation group differed less remarkably.Conclusion: The micro-arc oxidation of doxorubicin-cyclopeptide c(RGDfk)composite coating on pure titanium promotes the early proliferation and activity of MC3 T3-E1 osteoblasts,and the expression of focal adhesion kinase signaling pathway and MAPK signaling pathway-related proteins increases.