Role Of TFEB In Early Osteoblast Differentiation And The Relationship Between Serum Uric Acid And BMD In Men With T2DM

Part?:Role of TFEB in early osteoblast differentiationObjective: Osteoporosis is one of the main factors that affect the quality of life in the elderly.Abnormal function of osteoblasts play a key role in the process of the development of osteoporosis.Studies have shown that autophagy plays a significant role in regulating the osteoblast mineralization function,while TFEB transcription factor is an important regulator of autophagy.Therefore this study aims to explore: 1.The association between osteoblast differentiation and autophagy in cell line MC3T3-E1;2.Whether the transcription factor TFEB is influential on osteoblast differentiation function.Further clarification of the relationship among osteoblast differentiation,transcription factor TFEB and cell autophagy is needed,to provide certain theoretical basis for clinical prevention of osteoporosis and the development of new anti-osteoporosis drugs.Methods: 1.In this study,cell line MC3T3-E1 cells is chosen to carry on the induction of osteogenesis and detect the gene marker of autophagy & TFEB in different time of osteogenesis induction.2.Western blot is used to detect cell autophagy marker protein-LC3,to compare the change of the protein expression in different time of osteogenesis induction.3.Transmission electron microscope is adopted to detect autophagy structure.4.We use Stub RFP-Sens GFP-LC3 double fluorescent detection system in the laser scanning confocal microscope to observe the autophagosome joining together.5.RNA of the osteogenesis cells is collected to make the PCR chip of autophagy related gene analysis.6.We use si-TFEB slow virus to infect the cell line MC3T3-E1 cells,and culture them for osteogenetic differentiation,with Realtime PCR and Western blot,the marker gene of osteogenesis and the change of the level of autophagy are detected.Results: 1.During the differentiation of cell line MC3T3-E1 cells,the autophagy related gene and protein expression are rising.In the transmission electron microscope we can observe autophagy body with double membrane.In the laser scanning confocal microscope we can observe the gathering of GFP-RFP-autophagy body.The PCR chip clustering figure of autophagy genes display a variety of autophagy related gene expression level elevated during differentiation.The phenomena above suggest that autophagy level is rising in cell line MC3T3-E1 cells when it is in differentiation.2.During the osteogenetic differentiation,the osteogenetic differentiation marker gene in TFEB knockout cells is significantly lower than the control group,and the level of autophagy is also significantly lower than the control group.Conclusion: During the osteogenetic differentiation of cell line MC3T3-E1,the process of autophagy is activated,and the expression of TFEB rise.TFEB may regulate osteoblast differentiation through autophagy.Part?: The relationaship between serum uric acid and bone mineral density in Chinese men with T2DMObjective: Accumulating evidence suggests that oxidative stress is associated with osteoporosis.Serum uric acid(UA)is a strong endogenous antioxidant.Therefore,we investigated the relationship between the serum UA and BMD in Chinese men with T2 DM.Methods: In this cross-sectional study of 621 men with T2 DM,BMDs at lumbar spine(L2–4),femoral neck(FN),and total hip(TH)were measured by dual-energy X-ray absorptiometry(DXA).Serum levels of UA,calcium(Ca),25-OH vitamin D3(vit D3),parathyroid hormone(PTH),and creatinine(Cr)were also tested.Results: Data analyses revealed that serum UA levels were positively associated with BMD at all sites( < 0.05)in men with T2 DM after adjusting for multiple confounders.The serum UA levels were positively correlated with body weight( = 0.322),body mass index(BMI)( = 0.331),Ca( = 0.179),and Cr( = 0.239)( < 0.001)and were also positively associated with the concentrations of PTH( = 0.10, < 0.05).When compared with those in the lowest tertile of UA levels,men with T2 DM in the highest tertile had a lower prevalence of osteoporosis or osteopenia(adjusted odds ratio 0.54,95% confidence interval [CI] 0.31–0.95).Conclusion: Results suggest that higher serum uric levels in physiological level have positive effects on BMDs in Chinese men with T2 DM.The higher the serum uric level,the higher of BMDs.