| Background:Jaw defect can be resulted from many factors, e.g. surgical trauma, tumor and inflammation. Except for facial deformity, Jaw defect may result in serious functional disturbance (about language, deglutition and so on) and some physiological, psychological and social influences. Since 1912, when Macewen reported the successful recovery of mandibular defect with autogenous costal bone, the scholars from all over the world have carried out a large amount of researches on jaw defect restitution.Traditionally, a major measure for curing jaw defect is bone transplantation, including autogenous bone transplantation, variant and heterogeneity bone transplantation, and artificial bone substitution. In recent years, with the development of biology and material science, Tissue Engineering emerged and developed as a multi-disciplinary and newly-arisen marginal subject in the high-tech field. Presently,Tissue-based bone which is formed with Tissue Engineering becomes another hotspot of bone transplantation research.According to Chinese Pharmacopoeia, as a kind of traditional Chinese medicine, Eucommia ulmoids Oliv has the function of nourishing liver & kidney and strengthening muscles & bones. In China, Eucommia is a kind of rare tree species, and its bark requires 15～20 years' growing, while its leaves resource is abundant. Based on modem medical research, Eucommia leaf basically has the same chemical constituent and medicinal efficacy as its bark, so Eucommia bark can be replaced by its leaf [1]. The chemical constituents of Folium Eucommiae are as followes: 1) Phenylpropanoids compounds: sistosterol,ursolic acid,chlorogenic acid; 2) iridoids: eneommiol,geniposidic acid, geniposide, aucubin; 3) flavonoids : kaempferol, quercetin.The experimental research shows that the effective constituent of Euec can obviously accelerate the proliferation of osteocyte. It can be seen that Eucommia is a kind of traditional Chinese medicine with definite constituent and easy extraction method, and it's able to accelerate the cultivation of bone.In some particular conditions such as trauma, and with the catalysis of SOD and oxidase, the body can generate reactive oxygenspecies (ROS), such as superoxide anion (O2-, H2O2, HO ? ) . It plays an important role in cell signal transduction, phagocyte and wound recovery.Objectives:This paper discusses the function of Euec to the osteoblast cultivated in vitro, and it introduces how to choose the best consistency of Euec according to the results of in-vitro activity test. Then it discusses the molecular mechanism of Euec and its protective effect on osteoblast apoptosis caused by H2O2. Methods:It discusses the bone formation function of Eucommia leaf through cell proliferation experiment. Taking MC3T3-E1 cell oxygenation damage and apoptosis (caused by H2O2) as the experimental model, it carries out in-vitro Euec cell experiment, and gives an expression on cell proliferation, apoptosis rate and relevant apoptosis albumen. Then, by adopting MTT method, flow cytometer, Western blot and RT-PCR method, it determines the survival rate of cell, the percentage of apoptosis, the albumen expression of Caspase-3, -6, -7, -9 and the gene expression of Caspase-3, -6, -7, -9. At last, it carries out a research on the possible mechanism of Euec and its protective effect on MC3T3-E1 apoptosis caused by H2O2. Results:800umol/ml H2O2 can result in the apoptosis of MC3T3-E1 cell; Euec can remarkably restrain the cell oxygenation damage caused by H2O2, improve the survival rate of cell, reduce the percentage ofapoptosis, depress the albumen and the gene expression of Caspase-3,Caspase-6, Caspase-7, Caspase-9.Conclusion:Euec can promote the proliferation MC3T3-E1 cell, and it can be used for bone recovery; it can restrain the apoptosis of MC3T3-E1 cell caused by H2O2, relieve the MC3T3-E1 cell from oxygenation damage by H2O2; it plays an important role in anti-apoptosis, and its mechanism may be related to the suppression of activation of Caspase-3, -6, -7, -9.
|
PDF Full Text Request