Experimental And Clinical Study On The Association Between FGF9 Or Vitamin D And Osteoporosis

PART? THE EFFECT AND MECHANISM OF FGF-9 ON RANKL-INDUCED OSTEOCLASTOGENESISObjective To investigate the effect and possible mechanism of FGF9 on RANKL-stimulated osteoclastogenesis in vitro.Methods Osteoclasts were induced by bone marrow mononuclear phagocytes of mouse using medium with macrophage colony stimulating factor(M-CSF) of 30 ng/ml and receptor activator of nuclear factor-kappa B ligand(RANKL) of 50 ng/ml. We used two methods: 1) FGF9WT/WT(WT) and FGF9WT/S99N(HE) mouses were used to isolate bone marrow cells and induce osteoclasts as described previously. 2) Cells treated with different concentrations of FGF9(10ng, 20 ng, 50ng) were acted as experimental groups and the cells without FGF9 were defined as control group. ?-MEM with M-CSF, RANKL and FGF9 was replaced periodically until the mature osteoclasts appearing. Osteoclasts differentiation and activation were estimated via TRAP(tartrate-resistant acid phosphatase) staining. The morphology of osteoclast was observed by inverted phase contrast microscope. We used Image Pro Plus 6.0 to count the number of osteoclasts in each view. Statistically significant differences were determined by t-test analysis,using SPSS 21.0. Osteoclast differentiation related genes(Trap, Mmp9, Ctsk)were examined by real-time PCR.Results 1) TRAP positive multinuclear cells were observed under the microscope in all groups. But more TRAP positive multinuclear cells with larger bodies and more nuclei were found in the group stimulated by 20 ng FGF9. T-test analysis showed that the WT group had more mature osteoclasts than the HE group(P<0.05). Among the experimental group and the control group, the group stimulated by 20 ng FGF9 had the most mature osteoclasts while the control group had the least. The differences between each experimental group and the control group were statistically significant(P<0.05, P<0.005, P<0.05). 2) Compared with the WT group, the HE group decreased significantly in the m RNA levels of Trap and Mmp9(P<0.05, P<0.001).Conclusion FGF9 can increase the formation of osteoclasts from osteoclast precursors with a possible Trap and Mmp9-related way.PART ? STUDY ON VITAMIN D STATUS AND THE RELATIONSHIP BETWEEN VITAMIN D AND PTH LEVEL AND BONE TURNOVER MARKERS IN AGED MALESObjective To investigate the serum vitamin D level in aged males in Shanghai and the relationship between Vitamin D and PTH level,bone turnover markers.Methods Eight hundred and ninety-five elderly men in Shanghai(mean years 76) joined the study performed from September 2010 to September 2013. Serum 25-hydroxy vitamin D [25-(OH)D], serum calcium(Ca), serum phosphorus(P) Parathyroid hormone(PTH), Procollagen type I N-terminal propeptide(PINP) and ?-crosslaps of C-telopeptide of type I collagen(?-CTX) were measured in all the subjects. All subjects were divided into four groups according to their serum 25-(OH)D levels: 25-(OH)D<25nmol/L, 25-50 nmol/L, 50-75 nmol/L and >75 nmol/L.Results 1) 895 subjects aged 60~99 years and the mean age was 76 years. The average of 25-(OH)D was(43.52±21.97) nmol/L. 592 subjects(67%) were at the level of vitamin D deficiency(?50 nmol/L) and 223 cases(25%) were in vitamin D insufficiency(50-75 nmol/L). Only 8% were over 75 nmol/L. 2) Serum 25-(OH)D in different ages showed that 25-(OH)D level decreased with increasing age and the highest level was(46.27±20.76) nmol/L of the 60~69 years group.There was significant difference in serum 25-(OH)D level between age at 60~69 years group and other age groups(P<0.05). Correlation analysis showed that serum 25-(OH)D level was negatively correlated with age(r=-0.088,P=0.008). 3) The mean level of PTH was(55.74±29.06) pg/ml. Correlation analysis showed that serum 25-(OH)D level was negatively correlated with PTH, PINP and ?-CTX(r=-0.209,-0.109,-0.122,P<0.05) and had no correlation with BMI, P(P>0.05). Serum 25-(OH)D level was positively correlated with Ca(r=0.206,P=0).Conclusions Vitamin D deficiency or insufficiency was highly prevalent among aged males. Serum 25-(OH)D level was negatively correlated with PTH, age, PINP and ?-CTX.