Relationship of osteocalcin and matrix Gla protein gene polymorphisms to serum osteocalcin levels and bone mineral density in postmenopausal Korean women

OBJECTIVE: To investigate the relationship of osteocalcin and matrix Gla protein (MGP) gene polymorphisms to serum osteocalcin levels, and bone mineral density (BMD) in postmenopausal Korean women. DESIGN: The osteocalcin gene Hind III and MGP gene cytosine-adenine polymorphisms were analyzed in 267 postmenopausal Korean women. Serum osteocalcin, bone alkaline phosphatase, C-telopeptide of type I collagen, and BMD at the lumbar spine and femoral neck were measured. RESULTS: No significant differences in BMD of the lumbar spine and femoral neck were observed across MGP genotypes, whereas a significant lower BMD at the lumbar spine (but not at the femoral neck) was observed in women with the (h) allele (lower case 'h' signifies the presence of the Hind III site) in a dose-response manner. Serum osteocalcin levels among bone turnover markers studied were significantly higher in women without the 210-bp MGP (cytosine-adenine) allele, or with the osteocalcin hh genotype. CONCLUSIONS: The osteocalcin gene Hind III polymorphism is a genetic factor that is associated with BMD of the lumbar spine in Korean women, and Gla gene polymorphisms are associated with higher osteocalcin levels.     

白细胞介素6与钙感应性受体基因多态性对青春期女童骨量增长的交互作用

目的 探讨白细胞介素6(interleukin-6,IL-6)与钙感应性受体(calcium sensing receptor,CASR)基因多态性对青春期女童骨量增长的交互作用.方法 选择228名9-11岁半未月经初潮的健康女童进行两年追踪,采用双能X线骨密度仪检测对象追踪前后全身、左侧近端股骨(包括股骨颈、大转子、粗隆间和华氏三角区)和L1-L4腰椎骨矿含量(bone mineral content,BMC)和骨密度(bone mineral density,BMD),采用聚合酶链反应-限制性片段长度多态性技术检测IL-6-634C/G位点多态性,等位基因特异性突变分离扩增-PCR技术检测CASR A986S位点多态性.结果 176名女童完成整个研究.IL-6基因-634C/G和CASR基因A986S位点多态性与青春期女童骨量增长有关联,IL-6基因-634C/G位点CG+GG基因型女童全身和股骨大转子BMD较CC基因型分别低25.7%和20.6%,CASR基因A986S位点AS+SS基因型女童L1.L4腰椎BMC和华氏三角区BMD增长率较AA基因型分别低14.9%和51.3%,差异有统计学意义(P＜0.05).交互作用分析发现,同时具有IL-6基因-634C/G位点G等位基因和CASR基因A986S位点S等位基因的女童,其股骨颈和L1-L4腰椎BMC增长率最低.结论 同时具有IL-6基因-634C/G位点G等位基因和CASR基因A986S位点S等位基因的女童,可能是低骨量增长的危险人群.     

Non-association Between Polymorphisms of the Frizzled Receptor Genes and Bone Mineral Density in Postmenopausal Korean Women

We investigated the association between single nucleotide polymorphisms (SNPs) in the frizzled (FZD) genes in the Wnt signal pathway and circulating osteoprotegerin (OPG), soluble receptor activator of NF-κB ligand (sRANKL) levels, bone turnover markers, and bone mineral density (BMD) in postmenopausal women. The SNPs in the FZD1, FZD5, FZD6, FZD7, and FZD9 genes were analyzed by direct sequencing in 371 postmenopausal Korean women. Levels of serum OPG, sRANKL, osteocalcin, C-telopeptide of type I collagen, calcium, parathyroid hormone and calcitonin, and BMD at the lumbar spine and femoral neck were measured. The SNPs in the FZD1, FZD5, FZD7, and FZD9 genes, and in exon 2 of the FZD6 gene were not observed. No significant differences in the adjusted BMD of lumbar spine and femoral neck and serum levels of OPG, sRANKL, and bone markers were noted among the single or haplotype genotypes of the L345M and E664A SNPs in the FZD6 gene and the distributions of these single or haplotype genotypes were not different according to the bone mass status. In conclusion, the polymorphisms of the FZD genes are not associated with BMD of the lumbar spine and femoral neck, bone turnover markers, or circulating OPG-sRANKL in Korean women.     

Association of candidate gene polymorphisms with bone mineral density in community-dwelling Japanese women and men

Although bone mineral density (BMD) is a complex trait that is influenced by both genetic and environmental factors, heritability studies in twins and families have shown that genetic factors account for 60-85% of the variance in BMD. We examined the relations of six candidate gene polymorphisms to BMD in community-dwelling women and men. The 2238 subjects (1110 women, 1128 men) were aged 40-79 years and were randomly recruited to a population-based prospective cohort study of aging and age-related diseases in Japan. BMD at the distal and proximal radius was measured by peripheral quantitative computed tomography, and BMD for the total body, lumbar spine (L2-L4), right femoral neck, and right trochanter was measured by dual-energy X-ray absorptiometry. Genotypes for the 1019Cright curved arrow T (Pro319Ser) polymorphism of GJA4 and the 1462Aright curved arrow G (Lys469Glu) polymorphism of ICAM1 were determined with a fluorescence-based allele-specific DNA primer assay system, and those for the 386Gright curved arrow A (Ala99Thr) polymorphism of PLOD1, the Aright curved arrow G polymorphism of CNR2, the 1583Gright curved arrow A (Arg528Lys) polymorphism of ALAP, and the -514Cright curved arrow T polymorphism of LIPC were determined by melting curve analysis. The polymorphisms of ALAP and PLOD1 were associated with BMD in premenopausal women; those of ICAM1 and LIPC with BMD in postmenopausal women; that of CNR2 with BMD in premenopausal and postmenopausal women; and that of GJA4 with BMD in men. Among these polymorphisms, those of ICAM1, CNR2, and GJA4 were markedly associated with BMD. These results suggest that ALAP, PLOD1, ICAM1, LIPC, and CNR2 are susceptibility loci for reduced bone mass in Japanese women and that GJA4 constitutes such a locus in Japanese men. The polymorphisms of ICAM1 and CNR2 may confer susceptibility to postmenopausal osteoporosis in women, and that of GJA4 to osteoporosis in men.     

Association of vitamin D receptor and estrogen receptor gene polymorphisms with bone mass in postmenopausal Korean women

OBJECTIVE: To examine the relationship between vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphism and bone mineral density (BMD). DESIGN: Polymorphisms at the VDR FokI and ER PvuII and XbaI gene sites, serum bone-specific alkaline phosphatase, urinary N-telopeptide of type I collagen, and BMD at the lumbar spine and proximal femur were analyzed in 229 postmenopausal Korean women. RESULTS: The distribution of ER PvuII and XbaI and VDR FokI restriction fragment length polymorphisms was as follows: pp 39.3%, Pp 46.3%, PP 14.4%, xx 34.1%, Xx 61.1%, XX 4.8%. ff 17.0%, Ff 43.7%, and FF 39.3%, respectively (upper-case letters signify the absence, and lower-case letters signify the presence of the restriction site). After adjusting for potential confounding factors such as age, body mass index, and menopause duration, ER PvuII was independently associated with BMD at the lumbar spine and XbaI polymorphism BMD at the femoral neck. The lumbar spine BMD in the pp genotype was 7.5% lower than in the PP genotype, and the femoral neck BMD was 4.8% lower in the Xx genotype than in the xx genotype. By itself, the VDR FokI polymorphism was not related to BMD, but by combining the FokI genotype (FF) with ER genotypes, such as ppxx and the PpXx, the difference in the BMD at the Ward's triangle became significant. There were no significant differences in the levels of biochemical markers between the genotypes of three polymorphisms. CONCLUSION: ER polymorphisms, singly and in relation to VDR FokI polymorphism, influence bone mass in Korean women.     

Association of oestrogen receptor alpha gene polymorphisms with postmenopausal bone loss, bone mass, and quantitative ultrasound properties of bone

Background: The gene encoding oestrogen receptor α (ESR1) appears to regulate bone mineral density (BMD) and other determinants of osteoporotic fracture risk.

Objective: To investigate the relation between common polymorphisms and haplotypes of the ESR1 gene and osteoporosis related phenotypes in a population based cohort of 3054 Scottish women.

Results: There was a significant association between a common haplotype "px", defined by the PvuII andXbaI restriction fragment length polymorphisms within intron 1 of the ESR1 gene, and femoral neck bone loss in postmenopausal women who had not received hormone replacement therapy (n = 945; p = 0.009). Annual rates of femoral neck bone loss were ~14% higher in subjects who carried one copy of px and 22% higher in those who carried two copies, compared with those who did not carry the px haplotype. The px haplotype was associated with lower femoral neck BMD in the postmenopausal women (p = 0.02), and with reduced calcaneal broadband ultrasound attenuation (BUA) values in the whole study population (p = 0.005). There was no association between a TA repeat polymorphism in the ESR1 promoter and any phenotype studied, though on long range haplotype analysis subjects with a smaller number of TA repeats who also carried the px haplotype had reduced BUA values.

Conclusions: The ESR1px haplotype is associated with reduced hip BMD values and increased rates of femoral neck bone loss in postmenopausal women. An association with BUA may explain the fact that ESR1 intron 1 alleles predict osteoporotic fractures by a mechanism partly independent of differences in BMD.

     

维生素D受体基因起始密码和3‘端多态性与绝经后妇女骨密度的关系

目的：了解维生系D受体（vitamin d receptor,VDR)基因起始密码多态性和3'端多态性对北京地区汉族绝经后妇女骨密度（bone mineral density,BMD)值的影响是否具有协同作用。方法：应用聚合酶链反应－限制性片段长度多态性检测了110绝经后妇女VDR基因Fok 1和3'端多态性，同时用双能X线吸收法测定绝经后妇女腰椎2－4（L2－4）、股骨颈、Ward's三角和大转子区的BMD值。结果：被研究人群Fok I、Apa I、Bsm I和Taq I等位频率分布均符合Hardy-Weinberg定律。单独分析各基因型与绝经后妇女BMD值的关系，仅显示Bsm I基因型与BMD值有关联（P＜0．05）；协同分析Fok I基因型和Apa I、Bsm I、Taq I基因型与BMD值的关系，显示Fok I-Apa I基因型与绝经后妇女L2－4 BMD值显著相关（P＜0．001），而未见Fok I-Bsm I基因型与绝经后妇女各部位BMD值的关联，Fok I-Taq I基因型与股骨颈和大转子区部位BMD值有关联（P＜0．05）。此外，未发现VDR基因3'端多态性之间与各部位的BMD值有关联。结论：VDR基因Fok I多态性虽然与绝经后妇女BMD值无关联，但Fok I多态性和3'端多态性（Apa I和Taq I）对绝经后妇女BMD值的影响具有协同作用。     

Association of the MTHFR C677T polymorphism and bone mineral density in postmenopausal women: a meta-analysis

Osteoporosis is a condition characterized by low bone mineral density (BMD) and micro-architectural changes in the bone tissue. The risk of osteoporosis is partly determined by genetic factors. The role of C677T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene has been investigated in postmenopausal osteoporosis. However, the relationship between MTHFR polymorphism and BMD is still controversial. We carried out a meta-analysis of 5,833 subjects to evaluate the association of MTHFR and BMD in postmenopausal women. Databases of MEDLINE, Web of Science, Scopus and CNKI were retrieved for all publications relating to MTHFR polymorphism and BMD in postmenopausal women. Five eligible studies were selected for meta-analysis. All these articles studied the association of MTHFR polymorphism and BMD of the femoral neck and lumbar spine in postmenopausal women. Our analysis suggested that postmenopausal women with the TT genotype had lower femoral neck BMD than the women with the CC/CT genotype, and the weighted mean difference (WMD) was -0.01 g/cm² [95% confidence interval (CI): (-0.01, -0.01), P < 0.01]. However, BMD of the lumbar spine of postmenopausal women with the TT genotype was not significantly different from that of women with the CC/CT genotype. In the random effects model, the WMD between the TT and TC/CC genotype was -0.01 g/cm² [95% CI: (-0.04, 0.01), P = 0.32]. The C677T polymorphism of the MTHFR gene is associated with BMD of the femoral neck in postmenopausal women. Women with the TT genotype of the MTHFR gene have lower BMD, suggesting that the TT genotype may be a risk factor for postmenopausal osteoporosis.     

Association between osteoprotegerin (OPG), receptor activator of nuclear factor-kappaB (RANK), and RANK ligand (RANKL) gene polymorphisms and circulating OPG, soluble RANKL levels, and bone mineral density in Korean postmenopausal women

OBJECTIVE: To investigate the association between osteoprotegerin (OPG), receptor activator of nuclear factor-kappaB (RANK), and RANK ligand (RANKL) gene polymorphisms and circulating OPG, soluble RANKL (sRANKL) levels, and bone mineral density (BMD) in Korean postmenopausal women. DESIGN: The OPG gene A163G, G209A, T245G, and G1181C polymorphisms, the RANK gene C421T and C575T polymorphisms, and the RANKL rs12721445 and rs2277438 polymorphisms were analyzed in 385 Korean postmenopausal women. Levels of serum OPG, soluble RANKL, osteocalcin, C-telopeptide of type I collagen, parathyroid hormone, calcium, and phosphorus and BMD at the lumbar spine and femoral neck were measured. RESULTS: The A163G, G209A, and T245G polymorphisms in the OPG gene were in complete linkage. The RANK C421T and C575T polymorphisms and the RANKL rs12711445 polymorphism were not observed. An association with BMD was found only for the OPG G1181C polymorphism, and BMD at the lumbar spine in women with the CC genotype was significantly higher than in women with the GC or GG genotype, with a C allele dose effect. In itself, the RANKL rs2277438 polymorphism was not related to BMD, but by combining the RANKL genotypes with the GC genotypes of the OPG G1181C polymorphism, the association with BMD at the lumbar spine became significant. No significant differences in the levels of any biochemical marker among genotypes of these polymorphisms were found. CONCLUSIONS: The OPG gene G1181C polymorphism, alone and in combination with the RANKL rs2277438 polymorphism, was identified as a genetic factor associated with BMD of the lumbar spine in Korean women.     

Association of TNFSF11 gene promoter polymorphisms with bone mineral density in postmenopausal women

OBJECTIVES: The receptor activator of nuclear factor-kappaB ligand (RANKL) is recognized as one of the important regulators of osteoclastogenesis. The expression of the tumour necrosis factor superfamily, member 11 (TNFSF11) gene, which encodes for RANKL protein, is increased relative to the expression of osteoprotegrin in cases of senile osteoporosis with hip bone fracture. Our aim was to find polymorphisms in the TNFSF11 gene promoter and to investigate their possible association with bone mineral density (BMD). METHODS: The TNFSF11 gene promoter region was screened for the presence of new sequence variations by direct sequencing. DNA sequencing revealed the presence of four sequence variations: -290C>T, -643C>T, -693G>C and -1594G>A. Association of the discovered polymorphisms with BMD was investigated in 115 Slovenian postmenopausal women, using restriction fragment length polymorphism analysis. After a year, bone loss in the association with the identified sequence variations was evaluated in 43 postmenopausal women. RESULTS: Three of the discovered sequence variations (-290C>T, -643C>T, -693G>C) proved to be polymorphic, whereas variation -1594G>A was only found in one patient. The frequencies of genotypes were as follows: CC (27.8%), CT (43.5%), TT (28.7%) for -290C>T polymorphism; CC (23.5%), CT (47.8%), TT (28.7%) for -643C>T polymorphism; and GG (22.6%), GC (51.3%), CC (26.1%) for -693G>C polymorphism. A statistically significant association of genotype with BMD at the femoral neck was observed only in the -290C>T polymorphism. Genotype CC was associated with lower BMD than the TT genotype (P = 0.022). In polymorphism -693G>C, a significant difference in bone loss rate was observed in total hip (P = 0.011) and femoral neck BMD (P = 0.037). CONCLUSIONS: Four sequence variations were identified in the studied region of TNFSF11 gene promoter. Our results of preliminary clinical evaluation suggest that the -290C>T polymorphism in the TNFSF11 gene promoter could contribute to the genetic regulation of BMD.     

Genetic control of IL-1beta bioactivity through differential regulation of the IL-1 receptor antagonist

Regulation of IL-1 bioactivity by the IL-1 receptor antagonist (IL-1Ra) is critical for the preservation of normal vascular structure and function in mice. In humans, IL-1 bioactivity may be further fine-tuned by genetic polymorphisms. We recently proposed that an intronic polymorphism of the human gene encoding the IL-1R antagonist (IL1RN) is a genetic risk factor for the development of chronic cardiac allograft rejection. Here we aimed to establish a physiological basis for this susceptibility. Plasma and peripheral blood mononuclear cells (PBMC) were obtained from 55 healthy human volunteers, whose genotypes for four polymorphisms of IL1 family genes (IL1B, IL1R1 and IL1RN) were determined by PCR. IL-1beta and IL-1Ra production and release in PBMC cultures were studied by flow cytometry and ELISA. Functional and genotypic data were pooled and analyzed first by multivariate and, subsequently, by univariate statistical tests. We were able to confirm our observed association of IL1RN genotype with chronic cardiac allograft rejection using multivariate statistics. IL1RN genotype also emerged as the principal regulator of both constitutive and stimulated IL-1Ra and IL-1beta release. Allele IL1RN*2 was consistently associated with higher IL-1Ra and lower IL-1beta release, in a dosage-dependent manner. Conversely, IL1RN*2 carriage was associated with reduced production of the intracellular isoform of IL-1Ra. These genotypic effects were only observed with prolonged culture prior to stimulation and were not appreciably influenced by the presence of exogenous modulators of IL-1beta production. We conclude that IL1RN genotype is the principal determinant of IL-1beta bioactivity within theIL1 gene cluster in humans and discuss its putative role in disease.     

The existence of gender difference in IL-1Ra gene polymorphism.

Interleukin-1beta (IL-1beta) and its endogenous antagonist IL-1 receptor antagonist (IL-1ra) play an important role in various inflammatory responses. The production of IL-1 and IL-1ra is regulated by genotypic and nongenotypic factors and is different between men and women. The aim of this study was to examine the existence of gender difference in the genetic polymorphism of these two cytokines. The genotypes of IL-1beta-511 biallelic polymorphism and that of IL-1Ra (IL-1RN) penta-allelic polymorphism were determined in 319 healthy Jewish subjects, 156 female and 163 male, using PCR amplification. The results showed that there was a gender difference in IL-1Ra gene polymorphism expressed by a higher incidence of IL1RN*1/IL1RN*1 homozygotes and a lower occurrence of IL1RN*1/IL1RN*2 heterozygotes in men compared with women. Furthermore, allele IL1RN*1 was more frequent in men, whereas allele IL1RN*2 was more prevalent in women. There was no difference in IL-1beta gene polymorphism between the two genders. It is conceivable that the gender difference in IL-1Ra gene polymorphism found in the current study may affect IL-1 and IL-1ra levels. This diversity might be one of the causes for the sex differences in immune response observed in various conditions, such as autoimmune diseases, pain perception, and premature delivery.     

Evaluation of eNOS gene polymorphisms in relation to BMD in postmenopausal women

Objective

The aim of the present study was to evaluate the relations between T⁻⁷⁸⁶C and Glu298Asp polymorphisms of the endothelial nitric oxide synthase (eNOS) gene and BMD in postmenopausal Turkish women.

Methods

The T⁻⁷⁸⁶C and Glu298Asp polymorphisms were genotyped by PCR-RFLP method in 311 postmenopausal osteoporotic women (OP) and in 305 age-matched postmenopausal females (CG) with normal BMD.

Results

None of the SNPs of the eNOS gene was significantly associated with BMD at the lumbar spine, femoral neck, Ward's triangle and femoral trochanter in the combined group. Mean BMD values were therefore found to be similar across the genotypes in postmenopausal Turkish women. However, there was a significant association between the T⁻⁷⁸⁶C polymorphism and BMD values at the lumbar spine in the normal control group (P = 0.005), and at the femoral trochanter in the osteoporotic patients (P = 0.046). The mean value of the lumbar spine BMD in the normal controls was significantly higher in women with the TC genotype of the T⁻⁷⁸⁶C polymorphism than in women with the TT genotype (P = 0.0012). Women with the CC genotype of the T⁻⁷⁸⁶C polymorphism in the osteoporotic patients had significantly higher BMD value at the femoral trochanter than those with the TC (P = 0.018) and TT genotypes (P = 0.024). Frequencies of the TC heterozygotes for T⁻⁷⁸⁶C polymorphism were significantly higher among osteoporotic subjects than normal controls. Also, the CC and TT genotype frequencies of control group were significantly higher than those of the osteoporotic group at the femoral neck.

Conclusions

We conclude that, although the biological role of the nitric oxide synthases is well established, our study does not suggest that eNOS gene polymorphisms, T⁻⁷⁸⁶C and Glu298Asp, are major contributors to adult bone mineral density in the postmenopausal Turkish women.     

The vitamin D receptor FokI start codon polymorphism and bone mineral density in osteoporotic postmenopausal French women

This study examined the association between bone mineral density (BMD) and a T/C polymorphism in the first of the two initiation codons in the vitamin D receptor (VDR) gene. The polymorphism was detected using the restriction enzyme FokI, the F allele indicating absence of the first codon and the f allele its presence. The FokI genotype was determined in 124 postmenopausal osteoporotic French women who were 45-90 years old. The distribution of FokI genotypes in the osteoporotics did not differ significantly from that found in a control group. There were no significant differences by FokI genotype groups in our total sample of osteoporotic women for age, years since menopause, height, weight, and BMD at lumbar spine and femoral neck. However, when only those patients under the age of 75 years are analysed (98 subjects), those with the ff genotype (10% of the population) had a significantly lower BMD at the femoral neck than FF and Ff subjects. This suggests that the ff genotype of the VDR gene correlates with decreased BMD at the femoral neck in French postmenopausal women.     

Association of polymorphisms of the osteoprotegerin gene with bone mineral density in Japanese women but not men

Given that osteoprotegerin plays an important role in bone remodeling, the osteoprotegerin gene may be a candidate locus for susceptibility to osteoporosis. The relation of polymorphisms in the promoter of the osteoprotegerin gene to bone mineral density (BMD) was examined in a Japanese population-based prospective cohort study with randomly recruited subjects (1095 women and 1125 men for the 950T --> C polymorphism, 1094 women and 1127 men for the 245T --> G polymorphism). BMD at the radius was measured by peripheral quantitative computed tomography, and that for the total body, lumbar spine, right femoral neck, right trochanter, and right Ward's triangle was measured by dual-energy X-ray absorptiometry. Genotypes were determined with a fluorescence-based allele-specific DNA primer assay system. Among 950T --> C genotypes, BMD for the proximal radius was lower in premenopausal women with the CC genotype than in those with the TT or TC genotype; the difference in BMD between the two groups was 3.9% (P=0.0075). Among 245T --> G genotypes, BMD for the radius, total body, femoral neck, trochanter, and Ward's triangle was lower in postmenopausal women with the GG genotype than in those with the TT or TG genotype, the TT genotype, or the TG genotype; the differences in BMD between the GG genotype and the TT or TG genotype were 19.8% for the distal radius (P=0.0015), 13.1% for the proximal radius (P=0.0095), 11.2% for the total body (P=0.0013), 12.9% for the femoral neck (P=0.0067), 18.7% for the trochanter (P=0.0008), and 27.1% for Ward's triangle (P=0.0038). BMD was not associated with the 950T --> C or 245T --> G genotypes in men. The present results implicate the osteoprotegerin gene as a susceptibility locus for reduced BMD in Japanese women.     

Prevention of postmenopausal bone loss by low and conventional doses of calcitriol or conjugated equine estrogen

OBJECTIVES: Estrogen deficiency is the most common cause of postmenopausal osteoporosis and estrogen replacement is well known to retard postmenopausal bone loss. Calcium supplement alone is generally considered to be insufficient for the prevention of bone loss associated with estrogen deficiency while the role of calcitriol is unclear. In the present study we examined the efficacy different doses of estrogen or calcitriol in the prevention of postmenopausal bone loss in Thais. METHODS: The subjects consisted of 146 Thai women no more than 6 years postmenopausal. The subjects were randomly allocated to receive 750 mg supplemental calcium alone, calcium and conjugated equine estrogen (CEE) at 0.3 or 0.625 mg, calcium and calcitriol at 0.25 or 0.5 microg daily. Those receiving CEE also took 5 mg medrogestone for 12 days each month. BMD at L2-4 and femoral neck were measured at baseline 1 year and 2 years after treatments. Data were expressed as mean +/- S.E. RESULTS: Subjects on supplemental calcium alone had approximately 2.5% decreases in L2-4 (P < 0.05) and femoral BMD (P < 0.01) at 2 years. CEE (0.3 mg) resulted in 3.20 +/- 1.2% increase in vertebral BMD (P < 0.05) while no significant change in BMD was demonstrated at the femoral neck. Likewise, 0.625 mg of CEE induced 5.4 +/- 1.4% increase in vertebral BMD at 2 years (P < 0.001) without change in the femoral BMD. In regard to calcitriol, no significant change in vertebral or femoral BMD was demonstrated with either 0.25 or 0.5 microg calcitriol. CONCLUSION: We concluded that calcitriol is effective in the prevention of early postmenopausal bone loss in Thais. It represents an option for the prevention of osteoporosis in postmenopausal women who are contraindicated for estrogen replacement.     

Association between bone mineral density and LDL receptor-related protein 5 gene polymorphisms in young Korean men

Recently, It has been reported that the LDL receptor-related protein 5 (LRP5) regulates bone formation, and that mutations of the gene cause osteoporosis-pseudoglioma syndrome or high bone mass phenotypes. However, the mutations cannot explain a genetic trait for osteoporosis in the general population because of their rarity. From 219 Korean men aged 20-34 yr, we looked for six known polymorphisms causing amino acid changes in the LRP5 coding region, and investigated their association with bone mineral density (BMD) at the following anatomical sites: lumbar spine (L2-L4) and the left proximal femur (femoral neck, Ward's triangle, trochanter and shaft). We found that the Q89R polymorphism was significantly associated with BMD at the femoral neck and Ward's triangle (p=0.004 and <0.001, respectively). However, after adjusting for age, weight and height, a statistically significant association only occurred at the Ward's triangle (p=0.043), and a marginal association was observed at the femoral neck (p=0.098). No A400V, V667M, R1036Q and A1525V polymorphisms were found, and no statistically significant association was found between the A1330V polymorphism and BMD at any sites. Although we failed to demonstrate a clear association between the LRP5 polymorphism and peak bone mass in young men, the present study suggests that larger-scale studies on the Q89R polymorphism need to be performed.     

Association of polymorphisms in forkhead box C2 and perilipin genes with bone mineral density in community-dwelling Japanese individuals

Evidence suggests the existence of a close relation between lipid metabolism and bone remodeling. We hypothesized that polymorphisms of genes that play a role in lipid metabolism, such as those for forkhead box C2 (FOXC2) and perilipin (PLIN), might affect bone mineral density (BMD). We thus examined the possible relationships between a -512C --> T polymorphism of FOXC2 and a 1243C --> T polymorphism of PLIN to BMD in community-dwelling Japanese women and men. The subjects (1129 men, 1114 women for FOXC2; 1122 men, 1112 women for PLIN) were aged 40 to 79 years and were randomly recruited to a population-based prospective cohort study of aging and age-related diseases in Japan. Genotypes for FOXC2 and PLIN were determined with a fluorescence-based allele-specific DNA primer assay system. The -512C --> T polymorphism of FOXC2 was associated with BMD for the distal and proximal radius in men and in premenopausal women as well as with BMD for the distal radius and total body in postmenopausal women, with the T allele being related to reduced BMD. The 1243C --> T polymorphism of PLIN was associated with BMD for the total body, lumbar spine, femoral neck, and trochanter in men, with the C allele being related to reduced BMD. This polymorphism of PLIN was not associated with BMD in all women. These results suggest that FOXC2 is a susceptibility locus for reduced BMD in Japanese men and women, and that PLIN constitutes such a locus in Japanese men.     

绝经后妇女骨质疏松患者血清IGF-1、IGFBP-3与骨密度及骨代谢指标的关系

目的： 探讨胰岛素样生长因子-1（IGF-1）和胰岛素样生长因子结合蛋白-3（IGFBP-3）与绝经后妇女骨密度及骨代谢指标之间的关系。方法： 通过检测90例绝经后妇女骨质疏松患者及70例绝经后骨量正常的健康对照组血清IGF-1、IGFBP-3、骨钙素（BGP）、I型胶原异构C端肽（β-CTX）、雌激素（E₂）、降钙素（CT）、甲状旁腺激素（PTH）、钙（Ca）、磷（P）等指标，然后同用双能X线骨密度仪检测的两组研究对象的腰椎（L2-L4）侧位、左股骨颈骨密度进行比较。结果： 绝经后骨质疏松组妇女腰椎、股骨颈骨密度显著低于对照组（均P<0.01）；血清IGF-1、IGFBP-3、E₂、CT、BGP水平均低于对照组（均P<0.01）；血清β-CTX、PTH均高于对照组（均P<0.01），血清Ca、P两组之间无差异（均P>0.05）。骨质疏松组和对照组腰椎侧位、左股骨颈BMD均与IGF-1、IGFBP-3、E₂、BGP、CT水平呈正相关，与β-CTX、PTH水平呈负相关，而与血钙、血磷无明显关系。结论： IGF-1、IGFBP-3、E₂、BGP、CT、β-CTX、PTH血清水平与腰椎、左股骨质具有明显的相关性，通过检测上述指标可考虑作为筛查绝经后妇女是否容易患有骨质疏松症的一项有价值的生化参考指标。     

TNFRSF11B gene variants and bone mineral density in postmenopausal women in Malta

A number of polymorphisms in various genes have been identified and associated with bone mineral density (BMD) and with an increased risk of osteoporosis.

Objective

In this study, three single nucleotide polymorphisms (SNPs) within the TNFRSF11B gene were studied for association with an increased risk of osteoporosis in postmenopausal Maltese women (n = 126).

Methodology

Analysis was performed by PCR restriction fragment length polymorphism (RFLP) while BMD at the lumbar spine, femoral neck, Ward's triangle and trochanter was measured by DEXA.

Results

No significant association was observed between genotypes and BMD for all polymorphisms studied within this gene. Homozygotes CC (T⁹⁵⁰–C) were observed to have the highest BMD at all anatomical sites although statistical significance was not reached when comparing the three genotypes. A statistical significant difference was observed in the distribution of genotype frequencies for this polymorphism between normal individuals and those that were either osteopenic or osteoporotic at one or both anatomical sites, with the TT genotype associated more frequently with low BMD. The T⁹⁵⁰–C and G¹¹⁸¹–C polymorphisms were in strong linkage disequilibrium with each other but not with the A¹⁶³–G polymorphism further upstream in the OPG promoter. Statistical significance was reached when constructing haplotypes, where the A–T–G haplotype was found to be more frequent in individuals with low BMD.

Conclusions

These results indicate the possible role of TNFRSF11B gene variants in postmenopausal bone loss in women in Malta.