Changes in RANKL/OPG/RANK gene expression in peripheral mononuclear cells following treatment with estrogen or raloxifene

The RANKL/OPG/RANK pathway is the key mediator of osteoclastogenesis. Mononuclear cells may be implicated in post-menopausal osteoporosis. The effect of estrogen or raloxifene on bone resorption and the expression of RANKL/OPG/RANK in peripheral blood mononuclear cells (PBMCs) was examined. Twenty-nine women with post-menopausal osteoporosis were treated with estrogen (HRT) or raloxifene for 12 months. Bone mineral density (BMD) was measured at baseline and at 12 months at the spine and hip. Serum C-terminal telopeptide (CTX) and OPG were measured at baseline and at 1, 3, 6 and 12 months. PBMCs were isolated from 17 women and changes in RANKL, OPG and RANK mRNA were determined. The effects of estrogen or raloxifene in PBMCs in vitro were also assessed. BMD increased following treatment (lumbar spine % change mean [S.E.M.]: 4.3% [0.9], p<0.001). Serum CTX decreased (6 months: -43.7% [6.0], p<0.0001). Serum OPG declined gradually (12 months: -26.4% [4.4], p<0.001). RANKL, OPG and RANK gene expression decreased (6 months: RANKL 50.0% [24.8] p<0.001, OPG: 21.7% [28] p<0.001, RANK: 76.6% [10.2] p=0.015). Changes in OPG mRNA correlated with changes in BMD (r=-0.53, p=0.027) and CTX (r=0.7, p=0.0044). Down-regulation in RANKL, OPG, RANK mRNA and reduction in bone resorption was also seen in vitro. These results suggest that the expression of RANKL/OPG/RANK in PBMCs are responsive to the slowing in bone turnover/remodeling associated with treatment with estrogen or raloxifene. Further confirmatory studies are needed.     

不同程度老年骨质疏松患者血清BALP、OPG/PYR比值变化及其与骨密度、骨折发生的相关性分析

摘要 目的：分析不同程度老年骨质疏松患者血清骨特异性碱性磷酸酶(BALP)、骨保护素(OPG)/吡啶啉(PYR)比值变化及其与骨密度、骨折发生的相关性。方法：选择我院自2020年11月至2023年7月接诊的70例老年骨质疏松患者作为观察组,其中轻-中度骨质疏松44例、重度骨质疏松26例;另选70例老年非骨质疏松者作为对照组。检测所有受试者血清BALP、OPG/PYR比值、腰椎、股骨颈和髋部的骨密度(BMD),分析BALP、OPG/PYR比值与不同骨骼部位BMD的关系,使用受试者工作特征(ROC)曲线分析BALP、OPG/PYR比值对老年骨质疏松骨折的预测效能。结果：观察组血清BALP水平高于对照组,OPG/PYR比值小于对照组（P＜0.05）;重度骨质疏松组血清BALP水平高于轻-中度骨质疏松组,OPG/PYR比值小于轻-中度骨质疏松组（P＜0.05）;观察组腰椎、股骨颈及髋部的BMD均小于对照组（P＜0.05）;经Pearson相关性分析,腰椎、股骨颈及髋部的BMD与血清BALP水平呈负相关（P＜0.05）,与OPG/PYR比值呈正相关（P＜0.05）;经ROC曲线分析,血清BALP联合OPG/PYR比值预测老年骨质疏松骨折的AUC为0.890。结论：老年骨质疏松患者血清BALP水平升高、OPG/PYR比值减小,与病情严重程度及骨密度有关,联合预测骨折的效能较好,值得进一步研究应用。     

Adequate but not supplemental folic acid combined with soy isoflavones during early life improves bone health at adulthood in male mice

Previous investigations from our laboratory have demonstrated that neonatal exposure to soy isoflavones (ISO) improves bone outcomes in CD-1 mice at adulthood with greater benefits in females than males. This study determined whether early-life exposure to supplemental folic acid (FA) — that may enhance DNA methylation of target genes — in combination with ISO provides greater benefits to male bone development than ISO alone. CD-1 dams were randomized to a low (0 mg/kg diet), adequate (2 mg/kg diet) or supplemental (8 mg/kg diet) level of FA during pregnancy and lactation. Offspring received corn oil or ISO (7 mg/kg of body weight per day) from postnatal day 1–10. From weaning, males were fed adequate FA and studied to age 4 months. Offspring exposed to adequate FA+ISO had multiple benefits to bone health: higher (P<.05) bone mineral density (BMD) and greater (P<.05) resistance to fracture at the femur and lumbar spine than mice exposed to adequate FA alone. Exposure to supplemental FA+ISO resulted in higher (P<.05) serum osteoprotegerin (OPG), and a higher ratio of OPG to receptor activator for nuclear factor κβ ligand (RANKL) but did not result in greater BMD or strength at the femur or lumbar spine than supplemental FA alone. In conclusion, early-life exposure to adequate FA+ISO provided functional benefits to male bone development, while improvements induced by supplemental FA+ISO were limited to a higher level of serum OPG. Mechanistic studies are needed to better understand how FA and ISO improve bone development in male offspring.     

Osteoprotegerin--does it play a protective role in the pathogenesis of bone loss in obese perimenopausal women?

INTRODUCTION: Assessment of serum osteoprotegerin (OPG) concentrations in obese patients in comparison to healthy controls and evaluation of a possible correlation between OPG and other markers of bone turnover or calcitropic hormones. MATERIAL AND METHODS: 50 obese perimenopausal women without concomitant diseases (BMI 36.7 +/- 4.1 kg/m(2), mean age 50.4 +/- 4.9 yrs). The control group consisted of 19 healthy women (BMI 24.2 +/- 2.1 kg/m(2); mean age 53.8 +/- 5.1 yrs). In all patients serum concentration of OPG, C telopeptide of type I collagen containing the crosslinking site (CTX), osteocalcin, parathormone (PTH) and vitamin D (25-OH-D(3)) was assessed. Dual energy x-ray absorptiometry (the DXA method) of the lumbar spine and femoral neck was performed using a Lunar DPXL to measure bone marrow density (BMD). RESULTS: In obese perimenopausal women serum OPG, osteocalcin and 25-OH-D(3) levels were significantly lower, and the serum PTH level was significantly higher in comparison to healthy controls. A significantly positive correlation was found between serum OPG level and age in both obese and control subjects. CONCLUSION: The serum OPG level in obese perimenopausal women is significantly lower in comparison to healthy controls and does not correlate significantly with biochemical markers of bone turnover, calcitropic hormones and BMD. It probably cannot play a protective role in the pathogenesis of bone loss in obese perimenopausal women.     

Disturbance of the OPG/RANK/RANKL pathway and systemic inflammation in COPD patients with emphysema and osteoporosis

Background

Osteoporosis is one of the systemic features of COPD. A correlation between the emphysema phenotype of COPD and reduced bone mineral density (BMD) is suggested by some studies, however, the mechanisms underlying this relationship are unclear. Experimental studies indicate that IL-1β, IL-6 and TNF-α may play important roles in the etiology of both osteoporosis and emphysema. The OPG/RANK/RANKL system is an important regulator of bone metabolism, and participates in the development of post-menopausal osteoporosis. Whether the OPG/RANK/RANKL pathway is involved in the pathogenesis of osteoporosis in COPD has not been studied.

Methods

Eighty male patients (current or former smokers) completed a chest CT scan, pulmonary function test, dual x-ray absorptiometry measurements and questionnaires. Among these subjects, thirty patients with normal BMD and thirty patients with low BMD were selected randomly for measurement of IL-1β, IL-6, TNF-α (flow cytometry) and OPG/RANK/RANKL (ELISA). Twenty age-matched healthy volunteers were recruited as controls.

Results

Among these eighty patients, thirty-six had normal BMD and forty-four had low BMD. Age, BMI and CAT score showed significant differences between these two COPD groups (p < 0.05). The low-attenuation area (LAA%) in the lungs of COPD patients was negatively correlated with lumbar vertebral BMD (r = 0.741; p < 0.0001). Forward logistic regression analysis showed that only LAA% (p = 0.005) and BMI (p = 0.009) were selected as explanatory variables. The level of IL-1β was significantly higher in the COPD patients as compared to the normal controls (p < 0.05), but the difference between the two COPD groups did not reach significance. The levels of IL-6 and TNF-α among the three groups were significantly different (p < 0.05). The level of RANKL and the RANKL/OPG ratio were significantly higher in COPD patients with low BMD compared to those with normal BMD and the normal controls (p < 0.05), and correlated negatively with lumbar vertebral BMD, but positively with LAA%.

Conclusions

Radiographic emphysema is correlated with low BMD in current and former smokers with COPD. IL-1β, IL-6, TNF-α, and the osteoporosis-related protein system OPG/RANK/RANKL may have some synergetic effects on emphysema and bone loss in COPD.     

Polymorphism in vitamin D receptor and osteoprotegerin genes in Egyptian rheumatoid arthritis patients with and without osteoporosis

1α,25-Dihydroxyvitamin D3 upregulates the expression of the receptor activator of nuclear factor kB ligand (RANKL), and downregulates osteoprotegerin (OPG) expression. We tested the effects of polymorphisms in the vitamin D receptor gene (VDR), and OPG gene in rheumatoid arthritis (RA) patients and healthy controls and their relationship to bone mineral density (BMD) and development of osteoporosis. Three hundred and fifty women were evaluated, 200 women having RA and 150 healthy control. The subjects were genotyped for polymorphism at BsmI in VDR and A163G in OPG genes by polymerase chain reaction followed by restriction fragment length polymorphism analysis. BMD was also measured. In A163G, the G allele increased the risk for RA and for the development of osteoporosis. We found a significant association between lower hip (BMD-h) and genotype variants of VDR (BsmI) and OPG A163G in RA patients with osteoporosis. Our results suggested that OPG A163G polymorphism was associated with RA susceptibility and with the development of osteoporosis in these patients. Also, VDR and OPG genes are important candidates for osteoporosis in RA patients.     

Receptor activator of NF-[kappa]B ligand arrests bone growth and promotes cortical bone resorption in growing rats.

Receptor activator of NF-kappaB ligand (RANKL), produced by osteoblastic lineage cells and activated T cells, is an essential factor for osteoclast differentiation, activation, and survival. Therefore, RANKL is a focal point of therapies targeting bone diseases where there is an imbalance of bone metabolism in favor of bone resorption. The present study assesses the effects of exogenous RANKL on growing bone. RANKL (100 microg x kg-1x day-1 for 7 days) administered to Sprague-Dawley weanling rats caused major deficits in growth, appearance, and bone mineral densities (BMD). Urinary deoxypyridinoline crosslinks, a measure of bone turnover, were higher in the RANKL-treated rats (P = 0.031), and the bone mineral content was lower (P < 0.001). The final BMD in the RANKL-treated rats was lower (P = 0.039) than in the control rats (19 +/- 7 vs. 38 +/- 5 mg/cm3). Moreover, calculated cortical bone density in each bone slice (total BMD - trabecular BMD) indicated there was only 5% cortical bone remaining in RANKL-treated rats. We conclude that therapies targeting RANKL are likely to have effects on cortical as well as trabecular bone density.     

Dysregulated B Cell Expression of RANKL and OPG Correlates with Loss of Bone Mineral Density in HIV Infection

HIV infection is associated with high rates of osteopenia and osteoporosis, but the mechanisms involved are unclear. We recently reported that bone loss in the HIV transgenic rat model was associated with upregulation of B cell expression of the key osteoclastogenic cytokine receptor-activator of NF-κB ligand (RANKL), compounded by a simultaneous decline in expression of its physiological moderator, osteoprotegerin (OPG). To clinically translate these findings we performed cross-sectional immuno-skeletal profiling of HIV-uninfected and antiretroviral therapy-naïve HIV-infected individuals. Bone resorption and osteopenia were significantly higher in HIV-infected individuals. B cell expression of RANKL was significantly increased, while B cell expression of OPG was significantly diminished, conditions favoring osteoclastic bone resorption. The B cell RANKL/OPG ratio correlated significantly with total hip and femoral neck bone mineral density (BMD), T- and/or Z-scores in HIV infected subjects, but revealed no association at the lumbar spine. B cell subset analyses revealed significant HIV-related increases in RANKL-expressing naïve, resting memory and exhausted tissue-like memory B cells. By contrast, the net B cell OPG decrease in HIV-infected individuals resulted from a significant decline in resting memory B cells, a population containing a high frequency of OPG-expressing cells, concurrent with a significant increase in exhausted tissue-like memory B cells, a population with a lower frequency of OPG-expressing cells. These data validate our pre-clinical findings of an immuno-centric mechanism for accelerated HIV-induced bone loss, aligned with B cell dysfunction.     

The relationship between osteoclastogenic and anti-osteoclastogenic pro-inflammatory cytokines differs in human osteoporotic and osteoarthritic bone tissues

Background

Pro-inflammatory cytokines possess osteoclastogenic or anti-osteoclastogenic activities. They influence osteoclasts directly or via the receptor activator of nuclear factor κB (RANK), RANK ligand (RANKL) and osteoprotegerin (OPG) system. Recent evidence suggests that inflammation may play a role in osteoporosis (OP) and osteoarthritis (OA). We aimed therefore to determine whether there is a difference between both groups: first, in the expression of the osteoclastogenic and anti-osteoclastogenic cytokines, second, in correlation of these cytokines with bone mineral density (BMD) and levels of bone turnover markers (BTM) and third, in correlation between the expression of these cytokines and osteoclast specific genes and RANK/RANKL/OPG genes.

Methods

Human bone samples from 54 age and sex matched patients with OP or OA were collected during hip arthroplasty surgery. The expression of 25 genes encoding pro-inflammatory cytokines, their receptors, osteoclast specific genes and RANK/RANKL/OPG genes was measured using quantitative real-time PCR. Total hip, femoral neck and lumbar spine BMD and BTM in blood samples were measured. The comparison between OP and OA was assessed using Student''s t-test or Mann-Whitney U test and correlations between gene expression, BMD and BTM were determined using nonparametric correlation.

Results

The results demonstrated a higher expression of interleukin (IL)-6 and IL-1α in OP, and interferon (IFN)-γ in OA (p < 0.0005). Negative correlations of total hip BMD with tumor necrosis factor-α (TNF-α) in OA and with RANKL/RANK in OP were found (p < 0.05). Significant correlations with BTM were shown for IL-1α and IFN-γ in OP (rho = 0.608 and -0.634) and for TNF-α, IL-6 and transforming growth factor-β1 (TGF-β1) in OA (rho = 0.591, -0.521 and 0.636). Results showed OP specific negative correlations (IFN-γ with ITGB3, IFN-β1 with CTSK, tartrate resistant acid phosphatase (TRAP), CALCR, RANK, RANKL, IL-1α with CTSK, OPG, IL-17A with CALCR) and positive (TGF-β1 with CTSK, TRAP, RANK), and OA specific negative (IL-1α with osteoclast associated immunoglobulin-like receptor (OSCAR), TNF-α with RANK, RANKL, OPG) and positive (IL-6 with RANK, RANKL, OPG) correlations.

Conclusions

Our results demonstrate that the relationship between osteoclastogenic and anti-osteoclastogenic pro-inflammatory cytokines differs in human OP and OA bone and could present an important factor for characteristics of OP and OA bone phenotypes.     

胰岛素对2型糖尿病骨质疏松大鼠血清与骨OPG、RANKL表达的影响

目的:探讨胰岛素对2型糖尿病骨质疏松大鼠血清及骨OPG(osteoprotegerin)、RANKL(OPG receptor activator nuclear factork B)表达水平的影响。方法:以高脂高糖饲料喂养4周同时饮用3%果糖水导致胰岛素抵抗小鼠,再以小剂量链脲佐菌素(30mg/kg)腹腔注射1次,2周后诱导建立2型糖尿病小鼠模型。对照组动物则给予正常饲料及饮用水进行喂养。模型建立成功后,对模型2组大鼠进行胰岛素治疗,分别采用OPG和RANKLelisa试剂盒对正常动物模型和糖尿病动物模型血清和骨组织中OPG,RANKL含量进行比较分析,采用血糖分析仪对不同组动物的血糖进行比较分析,采用骨密度分析仪对动物的骨密度进行分析,了解高血糖对于骨密度及血清,骨组织中OPG,RANKL含量的影响以及胰岛素对高血糖骨质疏松造成的结果的影响。结果:相较于正常组大鼠,模型组大鼠血清及髂骨中OPG、血糖、糖化血红蛋白、髂骨密度表达显著下调(P0.05),而RANKL表达显著上调(P0.05),胰岛素处理的模型大鼠血清及骨中OPG含量较模型组大鼠显著升高,血清及骨组织中RANKL表达显著下调(P0.05)。结论:胰岛素能够显著降低2型糖尿病骨质疏松大鼠血清及骨组织中RANKL的表达,显著上调OPG的表达。     

Celiac disease association with CD8+ T cell responses: identification of a novel gliadin-derived HLA-A2-restricted epitope

One of the diagnostic hallmarks of the histological lesions associated with celiac disease is the extensive infiltration of the small intestinal epithelium by CD8(+) T cells of unknown Ag specificity. In this study, we report recognition of the gliadin-derived peptide (A-gliadin 123-132) by CD8(+) T lymphocytes from celiac patients. A-gliadin 123-132-specific IFN-gamma production and cytotoxic activity were detected in PBMCs derived from patients on gluten-free diet, but not from either celiac patients on gluten-containing diet or healthy controls. In contrast, A-gliadin 123-132-specific cells were isolated from small intestine biopsies of patients on either gluten-free or gluten-containing diets. Short-term T cell lines derived from the small intestinal mucosa and specific for the 123-132 epitope recognized human APC pulsed with either whole recombinant alpha-gliadin or a partial pepsin-trypsin gliadin digest. Finally, we speculate on a possible mechanism leading to processing and presentation of class I-restricted gliadin-derived epitopes in celiac disease patients.     

Bone mineral density and bone turnover in hyperprolactinaemia of various origins

INTRODUCTION: Osteopenia and osteoporosis because of hyperprolactinaemia caused by prolactinoma may be followed by an increased risk of fracture. There are no data on the bone effects of functional hyperprolactinaemia. The aim was to assess the influence of hyperprolactinaemia of various origins on bone turnover and density in different skeletal sites. MATERIAL AND METHODS: The study was carried out in 75 women (aged 30.53 +/- 7.8): Group I--32 women with prolactinoma and Group II--43 women with functional hyperprolactinaemia. Both groups of patients were subdivided into those with hypogonadism and those with normal gonadal function. The control group consisted of 29 healthy women aged (33.59 +/- 4.7). In all subjects PRL and bone turnover markers (BAP, OC, ICTP) were studied. BMD measurements (lumbar spine, forearm, proximal femur and total body) were carried out using DXA. RESULTS: Higher PRL concentrations were observed in patients than in controls. The values of bone turnover markers (BAP, ICTP) were shown to be higher in patient groups and subgroups than in controls. In patients with prolactinoma lumbar spine BMD was lower than in patients with functional hyperprolactinaemia and controls. Total body BMD was also lower, albeit to a lesser extent. CONCLUSIONS: Hyperprolactinaemia caused by prolactinoma in women influences bone metabolism unfavourably, more by the impact on the activity of bone turnover markers than on BMD. This provides an opportunity for earlier assessment of bone metabolism disturbances before the BMD changes can be observed. Functional hyperprolactinaemia does not determine such a harmful effect on bone metabolism as hyperprolactinemia due to prolactinoma.     

Gene–gene interactions in RANK/RANKL/OPG system influence bone mineral density in postmenopausal women

Receptor activator of nuclear factor κB (RANK) is one of the proteins in regulation of osteoclastogenesis via RANK/RANKL/OPG. Gene that codes for RANK protein (TNFRSF11A) was associated with osteoporotic fractures in a recent genome-wide association study. As variations in the RANK gene could alter its expression and activity, the aim of our study was to evaluate the influence of four RANK gene polymorphisms on bone mineral density (BMD) and biochemical markers.We evaluated 467 postmenopausal women and 117 elderly men. All subjects were genotyped for the presence of RANK polymorphisms ?670G>C, +34694C>T, +34901G>A and +35966insdelC. BMD and biochemical markers were measured.Significant associations of +35966insdelC with BMD at lumbar spine (BMD-ls), total hip (BMD-th) and femoral neck (BMD-fn) were found in postmenopausal women (p = 0.020, 0.024 and 0.034), but not in men. Significant gene–gene interaction was proved for two RANK polymorphisms in combination with OPG and RANKL polymorphisms studied previously in postmenopausal women. Firstly, RANK/RANKL (+34901G>A/?290C>T) combination was associated with BMD-fn, BMD-th and BMD-ls (p = 0.034, 0.016 and 0.050), and secondly, RANK/OPG combination (+35966insdelC/K3N) showed influence on BMD-fn and BMD-ls (p = 0.043 and 0.039).Our results suggest that gene–gene interactions between RANK and OPG, and RANK and RANKL influence BMD in postmenopausal women.     

仙灵骨葆对骨质疏松大鼠OPG/RANK/RANKL 表达的影响

目的:观察仙灵骨葆治疗骨质疏松模型大鼠后,对大鼠体内OPG/RANKL/RANK表达的影响。方法:卵巢摘除法建立SD大鼠骨质疏松模型,设立假手术组、对照组(单纯去卵巢组)、雌激素组(给予17β-雌二醇)和治疗组(给予仙灵骨葆)。术后1周开始给药,给药12周后检测各组大鼠股骨骨密度,ELISA法检测血清中OPG/RANKL含量,RT-PCR检测骨组织中OPG/RANK/RAN-KL mRNA表达,免疫组化检测骨组织中RANK的表达。结果:对照组大鼠骨密度显著低于假手术组;治疗组和雌激素组大鼠O-PG表达显著高于对照组,RANK及RANKL的表达显著低于对照组。结论:采用卵巢摘除法成功建立大鼠骨质疏松模型;仙灵骨葆可促进骨质疏松大鼠OPG的表达,并抑制RANK及RANKL的表达,对骨质疏松模型大鼠有治疗作用。     

The effect of long-term glucocorticoids on bone metabolism in systemic lupus erythematosus patients: the prevalence of its anti-inflammatory action upon bone resorption

The study was made to evaluate bone turnover in systemic lupus erythematosus (SLE) patients undergoing long-term glucocorticoid therapy. Thirty-eight female patients with established SLE were compared with a control group consisting from 160 age-matched healthy women. Serum concentrations of proinflammatory cytokines: interleukin-1alpha, interleukin-6, tumor necrosis factor-alpha, granulocyte-macrophage colony stimulating factor (GM-CSF) and some biochemical markers of osteoporosis (osteocalcin, total and bone alkaline phosphatase, procollagen type I carboxyterminal propeptide, carboxyterminal telopeptides of type I collagen--CTx) were measured. Additionally, morning urine excretions of deoxypyridinoline and calcium/creatinin ratios were determined. The forearm densitometry (DXA) was performed in all patients. Bone mineral content (BMC) and bone mineral density (BMD) in the SLE group was not significantly different from the controls, and no relationship was found between the glucocorticoid exposure and the BMC/BMD. However, biochemical markers of bone resorption--CTx and calcium/creatinin ratio--were significantly increased in the patient group. Our results suggest that BMD/BMC is preserved in glucocorticoid-treated SLE patients despite accelerated bone turnover.     

The usefulness of bone metabolic indices for the prediction of changes in bone mineral density after parathyroidectomy in patients with primary hyperparathyroidism.

Patients with primary hyperparathyroidism (pHPT) have reduced bone mineral density (BMD). Although pHPT causes high bone turnover, the exact metabolic bone markers useful for predicting changes in BMD after parathyroidectomy (PTX) remain elusive. The present study was performed to examine the relationship between bone metabolic indices and BMD changes after PTX in 29 pHPT Japanese patients, which received PTX successfully. BMD values were measured by dual-energy X-ray absorptiometry in the lumbar spine and distal one third of radius. As for bone metabolic indices, serum bone-type alkaline phosphates (BAP), serum osteocalcin (OCN), urinary deoxypiridinoline (Dpd), and urinary type I collagen cross-linked N-telopeptides (NTX) were measured. The study included 10 male and 19 female patients (17 postmenopausal). Urinary Dpd, but not NTX was significantly correlated with serum BAP and OCN. Either bone formation or bone resorption indices were significantly and highly correlated with Z-score of BMD in the radius, but not at lumbar spine. Urinary Dpd was significantly correlated with BMD changes at both lumbar spine and radius and at all time points over the two years after PTX. These correlations were most potent among bone metabolic indices in this study. The measurement of urinary Dpd would be useful for predicting long-term changes in BMD at radial and lumbar spine after PTX than other bone metabolic indices.     

Association between estrogen receptor alpha gene polymorphisms and bone mineral density in Polish female patients with Graves' disease

Graves' (GD) hyperthyroidism leads to reduced bone mineral density (BMD) accompanied by accelerated bone turnover. Ample studies have identified association between estrogen receptor (ESR1) gene polymorphism and decreased BMD and osteoporosis. In contrast, number of publications that link ESR1, BMD and Graves' disease is limited. The purpose of this study was to identify the association between ESR1 polymorphisms and BMD in premenopausal women with GD and to determine whether ESR1 polymorphic variants can predispose to GD. The study included 75 women aged 23-46 years with GD and 163 healthy controls. BMD was measured at lumbar spine and femoral neck. We investigated two SNPs in the ESR1 gene and analyzed genetic variants in the form of haplotypes reconstructed by statistical method. Three out of four possible haplotypes of the PvuII and XbaI restriction fragment length polymorphisms were found in GD patients: px (55.3 %), PX (33.3 %) and Px (11.4 %). Women homozygous for xx of XbaI and for pp of PvuII had the lowest BMD at lumbar spine. Moreover, the px haplotype predisposed to reduced lumbar BMD. No associations were observed for femoral neck BMD. No statistically significant relationship were found between ESR1 polymorphisms or their haplotypes and GD. These results indicate that the PvuII and the XbaI polymorphisms of ESR1 gene are associated with bone mineral density in premenopausal women with GD and may help to estimate the risk of bone loss particularly at lumbar spine. However, none of the ESR1 gene alleles predict the risk of GD in Polish female patients.     

Relationship between Body Mass Composition,Bone Mineral Density,Skin Fibrosis and 25(OH) Vitamin D Serum Levels in Systemic Sclerosis

A reduced bone mineral density (BMD) is observed in several rheumatic autoimmune diseases, including Systemic Sclerosis (SSc); nevertheless, data concerning the possible determinants of bone loss in this disease are not fully investigated. The aim of this study is to evaluate the relationship between BMD, body mass composition, skin sclerosis and serum Vitamin D levels in two subsets of SSc patients. 64 post-menopausal SSc patients, classified as limited cutaneous (lcSSc) or diffuse cutaneous (dcSSc) SSc, were studied. As control, 35 healthy post-menopausal women were recruited. Clinical parameters were evaluated, including the extent of skin involvement. BMD at lumbar spine, hip, femoral neck and body mass composition were determined by dual-energy X-ray absorptiometry. Serum calcium, phosphorus, alkaline phosphatase, urine pyridinium cross-links, intact parathyroid hormone and 25-hydroxyvitamin D (25OHD) were measured. BMD at spine, femoral neck and total hip was significantly lower in SSc patients compared to controls. In dcSSc subset, BMD at spine, femoral neck and total hip was significantly lower compared to lcSSc. No differences in both fat and lean mass were found in the three study groups even if patients with dcSSc showed a slightly lower total body mass compared to healthy controls. Total mineral content was significantly reduced in dSSc compared to both healthy subjects and lcSSc group. Hypovitaminosis D was observed both in healthy post-menopausal women and in SSc patients, but 25OHD levels were significantly lower in dcSSc compared to lcSSc and inversely correlated with the extent of skin thickness. These results support the hypothesis that the extent of skin involvement in SSc patients could be an important factor in determining low circulating levels of 25OHD, which in turn could play a significant role in the reduction of BMD and total mineral content.     

Effects of the administration of corticosterone,parathyroid hormone,or both,and of their withdrawal,on rat bone and cartilage histomorphometric parameters,and on osteoprotegerin and RANKL mRNA expression and proteins

We have studied the effects of the treatment with corticosterone (CORT), parathyroid hormone (PTH), or both (CORT + PTH), and of their withdrawal (CORT-rec and CORT + PTH-rec), on the osteoprotegerin (OPG) and receptor activator of nuclear factor-kB ligand (RANKL) localization and expression and on histomorphometric parameters in primary and secondary spongiosa of rat femur and tibia metaphyses. In the secondary spongiosa of the CORT group, the bone remodeling and the OPG/RANKL mRNA ratio decreased. In the PTH group, the bone turnover and the structural and connectivity indices increased, and the OPG/RANKL mRNA ratio fell; this ratio rose, however, in the primary spongiosa. In the CORT + PTH group, remodeling values intermediate between those of the CORT and PTH groups, were detected in the secondary spongiosa, where OPG and RANKL mRNA rose. Return towards control values was found in the recovery groups. The Cartilage Growth Plate Width was reduced in the CORT and CORT + PTH groups and returned to normal values in the recovery groups, while it was not affected by PTH. Independently of treatments, both OPG and RANKL mRNA and proteins were co-localized in the same cartilage and bone cells and in several bone marrow cells. In conclusion, the catabolic effects induced by CORT treatment occur together with an OPG fall and a RANKL rise. In the PTH group in which the bone turnover increase, the OPG and RANKL mRNA expressions differ in the primary and secondary spongiosa, confirming that the bone tissue in these sites can have different metabolic trends.