The Relationships Between Serum TGF-β With OPG And Leptin And Regional Difference Of BMD And The Effect Of Integrated Reference Databases On Diagnosis Of OP

The First Part The relationships between age-related TGF-β1 and TGF-P2 with OPG and leptin in womenObjective Transforming growth factor-beta 1 (TGF-β1), TGF-β2, osteoprotegerin (OPG), and leptin are important cytokines in the regulation of bone remodeling. However, the relationships among them were unknown. This study will investigate the relationship of TGF-β1 and TGF-β2 levels related to age with those of OPG and leptin in Chinese females.Methods A total of 459 healthy Chinese women in Changsha area, aged 25-80y (49.6±10.5), were randomly selected. The study involved a total of 94 premenopausal women,160 perimenopausal women, and 205 postmenopausal women. Fasting morning (7-9 am) blood samples were collected and centrifuged within 1 h. We measured serum TGFβ1, TGF-β2 and leptin concentrations with a sensitive enzyme-linked immunosorbent assay (ELISA) kit (USA), OPG with an ELISA kit (Austria), and quantified using aμQuant Universal Microplate Spectrophotometer (Bio-Tek Instruments, Inc., Winooski, VT). All calculations were performed using SPSS V13.0 for Windows software.Results The serum TGF-β1, OPG and leptin concentrations follow skewness distribution, but the logarithmic values of their concentrations demonstrate an approximately normal distribution; both the serum TGF-β2 concentrations and its logarithmic values demonstrate approximately normal distribution. The mean values of concentrations of age related serum TGF-β1 OPG and leptin were significantly higher than those of their geometric mean values. The TGF-β1 level is significantly negatively correlated with age (r=-0.335, P=0.000) and that the TGF-β2 level is positively correlated with age (r=0.230, P=0.000). The relationships of serum OPG and leptin with age adopted a cubic regerssion model optimized for goodness-of-fit. The geometric mean values (±standard deviation) of the serum TGF-β1, OPG, and leptin in Chinese females were (29.7±1.69)μg/1, (3.81±1.96) pmol/1, and (10.5±2.01)μg/1, respectively, the arithmetic mean value of TGF-β2 were (13.7±3.86)μg/L. Further, the serum TGF-β1 levels of postmenopausal women were significantly lower than those of perimenopausal and premenopausal women (24.3±1.59 vs 33.4±1.69 and 37.6±1.64, respectively), while the TGF-β2 levels of postmenopausal women were significantly higher than those of perimenopausal and premenopausal women (14.6±3.91 vs 13.5±3.93 and 11.7±2.68, respectively), the mean values of premenopausal period, perimenopausal period and postmenopausal period showed a remarkably echelon increaseing. The mean values of serum leptin concentrations had no correlation with menopausal status. There were no significant differences of mean values of serum TGF-β1 and TGF-β2 among normal body weight group (NW), overweight group (OW), and obese group (OB); the mean OPG level is significantly lower in OW than in NW and OB. In these four cytokines, only leptin concentrations changed with BMI, that is, the mean value of leptin was the highest in OB, followed by OW and NW, and exhibited an increasing trend. The TGF-β1 level was found to be significantly negatively correlated with both TGF-02 (r=-0.261, P=0.000) and OPG (r=-0.313, P=0.000) levels; a significantly positive correlation was found between the TGF-β1 and leptin levels (r=0.164, P=0.000) and between the TGF-(32 and OPG levels (r=0.432, P=0.000), and no correlation is observed between TGF-β2 and leptin.Conclusion This research reveals the relationships between age-related serum TGF-β1 and TGF-β2 with OPG and leptin in Chinese adult women, and provides reliable reference values of these cytokines for diagnoses and therapy of disease. The Second Part The regional differences of age-related BMD and bone loss rateObjective Osteoporosis (OP) is recognized as a "silent epidemic disorder", it caused a major public health problem in both developed and developing countries alike. Bone mineral density (BMD) is affected by genetic, geographical, environmental, lifestyle and other factors. The aim of this study is to investigate the regional differences of BMD changed with age and bone loss rates of Chinese females.Methods A total of 6762 healthy Chinese women from different areas, aged 20-90 years, were randomly selected. The subjects are from Chengdu, Sichuan (n=735), Changsha (n=1157), Guangzhou (n=732), Jiaxing, Zhejiang (n=929), Shanghai (n=2111) and Nanjing (n=1058), respectively. All subjects'BMD at PA spine (L1-L4) and various skeletal regions of hip (including the femoral neck, trochanter, Ward s triangle, and total hip) were measured by a fan-beam dual-energy X-ray absorptiometry bone densitometer (DXA, Lunar, USA). The best-fitting regressive models were used to fit the curve of BMD changed with age at various skeletal regions, then calculate BMD loss rate changed with age from the curve, and compare the BMD and bone loss rate of different areas women.Results (1) The mean values of height(152.1±6.77 cm)and weight (52.1±9.21 kg) in Chengdu females were lowest, and were remarkably lower than those of Changsha (154.8±6.10 cm and 54.7±8.93 kg), Guangzhou (154.4±6.29 cm and 54.2±9.34 kg), Jiaxing (156.1±6.19 cm and 56.1±8.89 kg), Shanghai (156.4±6.17 cm and 57.5±8.12 kg), and Nanjing (159.0±5.51 cm and 58.2±8.30 kg) females; the mean values of height and weight in Changsha and Guangzhou women were significantly lower than those of Jiaxing, Shanghai and Nanjing women, while these index of Nanjing women were remarkedly higher than Shanghai and Jiaxing women.(2) In total age range, the mean values of BMD at spine were 0.905±0.182 g/cm2 in Chengdu,0.967±0.184 g/cm2 in Changsha, 0.946±0.201 g/cm2 in Guangzhou,0.960±0.184 g/cm2 in Jiaxing, 1.010±0.166 g/cm2 in Shanghai, and 0.998±0.176 g/cm2 in Nanjing, respectively. BMD at spine in Chengdu women was significantly lower those of other regional women, BMD at spine in Changsha women were significantly higher than those of Chengdu and Guangzhou females, while lower than those of Shanghai and Nanjing females. The mean value of BMD at femoral neck was 0.783±0.159 g/cm2 in Chengdu women, 0.832±0.162 g/cm2 in Changsha women,0.802±0.164 g/cm2 in Guangzhou,0.847±0.140 g/cm2 in Shanghai,0.829±0.151 g/cm2 in Nanjing, respectively. BMD at femoral neck of Chengdu and Guangzhou females were lowest, and those of Jiaxing and Shanghai females were greatest, BMD at femoral neck of Chengdu women was significantly lower than any other regional women. The mean value of BMD at trochanter in Chengdu females was 0.663±0.132 g/cm,in Changsha females was 0.689±0.151 g/cm2, in Guangzhou females was 0.687±0.145 g/cm2, in Jiaxing females was 0.705±0.133 g/cm2, in Shanghai females was 0.710±0.126 g/cm2, in Nanjing females was 0.682±0.126 g/cm2, respectively. The BMD at trochanter in Chengdu area was significantly lower than any other regions, and BMD at trochanter were similar among Changsha, Guangzhou and Nanjing females, which were significantly lower than Jiaxing and Shanghai females. The mean value of BMD at total hips in Changsha women were 0.864±0.168 g/cm2, in Jiaxing women were 0.885±0.152 g/cm2, in Shanghai women were 0.879±0.140 g/cm2, in Nanjing women were 0.893±0.145 g/cm2. BMD at total hips of Changsha females were remarkably lower than Jiaxing, Shanghai and Nanjing females, meanwhile, the index of Nanjing females were remarkably higher than those of Shanghai females.(3) The cubic curve regression was the best-fit model for the relationship between BMD at different skeletal regions and age in different areas women, that is, the scatter distributions of BMD were consistent with the curve change best, meanwhile, the coefficient of determination of the curve equation was the biggest. Compared the curves of BMD changed with age at different skeletal sites, all of them showed that the curve value of BMD at lumber spine was the biggest. After the occurrence of peak value of BMD at Ward's triangle, the curve showed a rapid decline trend, which declined faster than lumber, femoral neck, trochanter and total hips. (4) The bone loss of Guangzhou and Jiaxing females started at 35yr by calculated BMD at lumber spine curve, while the bone loss of other regional females started at 40yr. The total loss rate of BMD curve at lumber spine of Chengdu and Guangzhou females were significantly larger than that of Changsha, Jiaixng, Shanghai and Nanjing females. The BMD loss of femoral neck in Chengdu, Changsha and Guangzhou females started in 35yr age group, then Jiaxing, Shanghai and Nanjing started in 40yr age group. At 85yr, the BMD loss rate of femoral neck in Guangzhou women was biggest,40.6% which was significantly bigger than Jiaxing, Nanjing and Shanghai, while in Nanjing was lowest,31.7%; the bone loss rate in Chengdu women was similar to Guangzhou women. The BMD loss rates at trochanter in Changsha and Guangzhou were 43.1% and 39.1%, respectively, which were the largest among these areas, while the loss rate in Chengdu and Nanjing women were 29.6% and 28.3%, respectively, which were the lowest. At Ward's triangle, the earliest PBMD of Chengdu and Guangzhou females occurred at 25yr, while the occurrence of PBMD of other regional women was 30yr. At 85yr, the BMD loss rate of Ward's triangle was largest, which all were nearly or more than 50%, except Jiaxing and Nanjing women, and the loss rate of Changsha, Guangzhou, Jiaxing, and Nanjing women were 53.8%,53.3%,45.2% and 42.3% respectively. The BMD loss rates in Chengdu, Changsha and Guangzhou women were significantly larger than those of Jiaxing, Shanghai and Nanjing women.(5) The BMD at lumber spine, femoral neck, trochanter and total hips in various regional women were significantly positively correlated with height (r=0.270-0.470, all P=0.000) and weight(r=0.151-0.519, all P=0.000). The correlation coefficients of BMD at lumber spine, femoral neck, Ward's triangle and total hips with height were always larger than those of BMD with weight and BMI, which suggesting that BMD had closer relationship with height than that of weight and BMI, moreover, the effect of height on BMD was bigger than that of weight and BMI on BMD.Conclusions There were significant differences among age related BMD and bone loss rates at various skeletal sites in different regional women, BMD of women located at southeast areas Jiaxing, Shanghai and Nanjing were remarkably higher than that of women located at west area Chengdu and central south areas Changsha and Guangzhou, the main reasons why BMD of women in southeast areas were higher than that of west and central south areas women maybe related to height and weight. The Third Part The comparison of BMD reference databases between multi-centers and various regions and the effect on diagnosis of OPObjective The measurement of BMD for diagnosing osteoporosis (OP), evaluating changing of bone mass under various disease condition and predicting risk of fracture has been obtained the widespread application in the all kinds of clinical domain. BMD reference database (reference curve) is the reference value for diagnosis of OP, which will directly influence the accuracy of diagnosis results. This study will investigate the differences between BMD reference databases of various areas in Chinese females and multiple centers integrated reference databases and their influences on diagnosis of OP.Methods A total of 6762 healthy Chinese women, aged 20-90y, were randomly selected from Chengdu, Sichuan (n=735), Changsha (n= 1157), Guangzhou (n=732), Jiaxing, Zhejiang (n=929), Shanghai (n= 2111) and Nanjing (n=1058) respectively. All subjects'BMD at PA spine (L1-L4) and various skeletal regions of hips (including the femoral neck, trochanter, Ward s triangle, and total hip) were measured by a fan-beam dual-energy X-ray absorptiometry bone densitometer (DXA, Lunar, USA). Establish multiple centers integrated BMD reference databases and different regional BMD reference databases, then compare the differences of these two BMD reference databases and diagnosis of OP.Results (1) At lumber spine, BMD reference curves of Chengdu, Changsha and Guangzhou women were significantly lower than the multiple centers integrated reference curve, while BMD reference curve of Jiaxing women had no difference with the multiple centers integrated reference curve, and BMD reference curves of Shanghai and Nanjing women were significantly higher than the multiple centers integrated reference curve. At femoral neck, BMD reference curves of Chengdu and Guangzhou women were significantly lower than the multiple centers integrated reference curve, and BMD reference curve of Jiaxing women were significantly higher than the multiple centers integrated reference curve, meanwhile, BMD reference curves of Changsha, Shanghai and Nanjing women had no difference with the multiple centers integrated reference curve; BMD reference curves of Changsha completely coincided with the multiple centers integrated reference curve. At trochanter, only BMD reference curve of Jiaxing women had remarkably difference with the multiple centers integrated reference curve, and BMD reference curves of other regional women had no remarkably difference with the multiple centers integrated reference curve. At total hips, BMD reference curves of Changsha, Jiaxing, Shanghai and Nanjing women all had remarkably differences with the multiple centers integrated reference curve.(2) The peak BMDs (PBMD) at different skeletal sites of various areas and multi-centers women occurred between 26-37yr:PBMD at lumber spine occurred at 31-35yr, PBMD at femoral neck occurred at 29-35yr, PBMD at trochanter occurred at 29-37yr, PBMD at Ward's triangle occurred at 26-32yr, PBMD at total hips occurred at 31-36yr, PBMD at various skeletal sites lasted for almost one year. At lumber spine, the difference of PBMD between Guangzhou and multi-center women were-0.05%, which was the smallest, while that of Chengdu women was largest,-2.23%. At femoral neck, the difference of PBMD between Chengdu and multi-center women were 1.14%, which was the largest, while that of Guangzhou women was smallest,-0.28%. At trochanter, the difference of PBMD between Nanjing and multi-center women were-3.73%, which was the largest, while that of Jiaxing women was smallest,-0.72%. At total hips, the differences of PBMD between Changsha, Jiaxing, Shanghai and Nanjing with multi-center women were all smaller than 1%, and the difference of PBMD between Shanghai and multi-center women was only 0.06%.(3) The biological variability (BV) of PBMD in various areas and multi-centers women at lumber spine, femoral neck, trochanter, Ward's triangle and total hips were 9.33%-11.2%,11.6%-14.8%, 11.6%-15.2%,12.8%-18.7%and 10.5%-13.5%, respectively, and the BV at Ward's triangle was largest. At lumber spine, the BV of Guangzhou women was smallest (9.33%), the BV at femoral neck, trochanter, Ward's triangle and total his in Shanghai women were all smallest; while those of Jiaxing women were largest. At femoral neck, BMD of Shanghai females decreasing or losing 29.0% (2.5×11.6%) can be diagnosed OP, nevertheless, BMD of Jiaxing females decreasing or losing 37.0% (2.5×14.8%) can be diagnosed OP.(4) From WHO diagnostic criteria, the detection rates of OP at lumber spine in Changsha, Jiaxing and Shanghai women by adopted multi-center integrated reference databases (CD) were 48.9%,42.4% and 31.6%, respectively; while the detection rates of OP by adopted located reference databases (LD) were 41.0%,33.8% and 37.0%, respectively. The detection rates of OP by used CD in Changsha and Jiaxing females were significantly higher than those of LD, but it was opposite in Shanghai females; the detection rates of OP by used CD in Chengdu, Guangzhou and Nanjing females were similar to those of LD. At femoral neck, the detection rates of OP by used CD and LD in Chengdu women were 29.7% and 20.4% respectively, in Guangzhou women were 33.3% and 26.6% respectively, in Jiaxing women were 17.3% and 7.3% respectively, in Shanghai women were 13.2% and 19.0% respectively; the OP detection rates of CD in Chengdu, Guangzhou and Jiaxing women were remarkedly higher than those of LD, but it was opposite in Shanghai women, and there was no difference between these two index in Changsha and Nanjing women. By using the diagnostic criteria drafted by China Gerontology Association the OP Committee, there was no significant difference among various areas women.Conclusion There were some significant differences of BMD reference curve between multi-centers women and located women and peak BMD. The OP detection rates of multi-centers reference databases had some differences with located reference databases. The multi-centers reference databases weren't completely fit to located women for diagnosing OP.