Vitamin D-Binding Protein Levels in Female Patients with Primary Hyperparathyroidism

ObjectiveTo determine whether low levels of vitamin D-binding protein (DBP) are related to 25-hydroxyvitamin D (25[OH]D) deficiency in female patients with primary hyperparathyroidism (PHPT).MethodsTwenty-five female patients with PHPT (serum calcium level >10.2 mg/dL and intact parathyroid hormone (iPTH) level >66 pg/mL) and 25 healthy age- and body mass index-matched female control subjects were xaminod. Serum calcium and iPTH levels were determined by commercial laboratories. Levels of 25(OH)D and 1,25-dihydroxyvitamin D (1,25[OH]₂D) were determined by radioimmunoassay, and DBP level was determined by enzyme-linked immunosorbent assay.ResultsSerum iPTH and calcium levels were higher in PHPT patients than control subjects (P<.001). Levels of 25(OH)D, albumin, and DBP were lower in the serum of PHPT patients than control subjects (P<.01). There were no significant differences in 1,25(OH)₂D and free 25(OH) D levels between PHPT patients and control subjects. DBP level was inversely correlated with calcium (r = -0.47; P<.01) and iPTH (r = −0.31; P<.05) levels. The 25(OH)D level correlated positively with both DBP (r = 0.28; P <.05) and albumin (r = 0.44; P<.05) levels.ConclusionsBoth serum 25(OH)D and DBP levels were lower in female patients with PHPT compared with control subjects. We suggest that a low DBP level contributes to the low 25(OH)D level observed in female PHPT patients. The etiology of the decrease in DBP and its relationship to calcium, 25(OH)D, and PTH levels require further investigation. (Endocr Pract. 2013;19:609-613)     

Vitamin D,Parathyroid Hormone,and Heart Failure in A Chinese Elderly Population

ObjectiveHeart failure (HF) is a major cause of morbidity and mortality worldwide. Low vitamin D status has been shown to be associated with increased risk of developing cardiovascular disease. In this study, we examined the association between vitamin D and parathyroid hormone (PTH) levels and HF in and elderly population in China.MethodsA population-based cross-sectional study was conducted in the spring of 2013 among 2,047 community-dwelling healthy individuals, aged 60 to 101 years. 25-Hydroxyvitamin D (25[OH]D) was measured using a chemiluminescence assay. PTH levels were measured with an electrochemiluminescence immunoassay.ResultsA total of 2,047 participants, including 1,121 women (54.7%), were evaluated in 2013. The median concentrations of serum 25(OH)D and PTH for the entire group were 16.1 ng/mL and 41.5 pg/mL, respectively. Serum 25(OH)D and PTH levels were associated with serum N-terminal pro-brain natriuretic peptide levels and left ventricular ejection fraction in a multivariate adjusted linear regression analysis (P < .05). In logistic regression analyses, serum 25(OH)D and PTH levels were associated with a risk of HF in single and multiple regression models (P < .05). Compared with patients with 25(OH)D levels between 30.0 and 44.9 ng/mL, patients with 25(OH)D levels less than 10 ng/mL had a higher mean hazard ratio for HF (2.88; 95% confidence interval, 1.59 to 4.38).ConclusionSerum 25(OH)D and PTH levels are independently associated with risk of HF in a Chinese elderly population. (Endocr Pract. 2014;21:30-40)     

Serum osteocalcin levels do not change during rapidly induced hypercalcemia in healthy subjects.

Since osteocalcin has been suggested to play a role in calcium homeostasis, we investigated its serum levels in 6 healthy subjects during a rapid calcium infusion. Serum levels of intact parathyroid hormone (PTH), 25-hydroxyvitamin D [25-(OH) D3] and 1,25-dihydroxyvitamin D [1,25-(OH)2 D3] were also determined. The calcium infusion increased plasma-ionized calcium levels from 1.25 +/- 0.04 to 1.54 +/- 0.07 mmol/l at 30 min (p less than 0.05). Concomitantly, serum levels of intact PTH declined from 2.1 +/- 0.9 to 0.2 +/- 0.3 mmol/l (p less than 0.05). In contrast, serum osteocalcin levels did not change. Further, during calcium infusion, serum levels of 1,25-(OH)2 D3 decreased from 81 +/- 17 to 75 +/- 15 pmol/l (p less than 0.05) whereas serum levels of 25-(OH) D3 did not change. The results therefore suggest that calcium per se does not influence osteocalcin secretion.     

Low Free (But Not Total) 25-Hydroxyvitamin D Levels in Subjects with Normocalcemic Hyperparathyroidism

Objective: Normocalcemic primary hyperparathyroidism (NPHPT) is characterized by elevated parathyroid hormone (PTH) levels with persistently normal calcium levels. The diagnosis of NPHPT assumes the absence of secondary causes of elevated PTH levels. The objective of the current study was to examine levels of free 25-hydroxyvitamin D (25&lsqb;OH]D) in NPHPT subjects and healthy controls.Methods: Ten NPHPT subjects and 20 controls who were age, sex, race, and body mass index (BMI) matched were examined. The diagnosis of NPHPT was made if subjects had (1) a serum calcium level of 8.6 to 10.4 mg/dL, total 25(OH)D 30 to 40 ng/mL, and intact PTH (iPTH) ≥66 pg/mL; and (2) normal renal and liver function. Serum total 25(OH)D levels were measured by radioimmunoassay, and free 25(OH)D levels were determined using an enzyme-linked immunoassay.Results: Mean age of NPHPT subjects was 59.9 ± 5.4 years, and mean BMI was 28.4 ± 2.3 kg/m², which was not significantly different from the mean age and BMI of the control subjects. Mean total 25(OH)D level was 31.9 ± 1.7 ng/mL in NPHPT subjects and did not differ from that of the controls (32.7 ± 3.3 ng/mL; P = .52). However, mean free 25(OH)D was 5.0 ± 0.9 pg/mL in NPHPT subjects, which was 20% lower compared to the mean of the controls (6.2 ± 1.3 pg/mL; P = .013). Serum iPTH levels were inversely correlated with levels of measured free 25(OH)D (r = -0.42; P<.05) but did not correlate with levels of total 25(OH)D (r = -0.14; P>.10).Conclusion: Measured free 25(OH)D levels are lower in NPHPT subjects than in healthy control subjects. We suggest that some NPHPT subjects may actually have secondary hyperparathyroidism based on their free 25(OH) D levels.Abbreviations: 25(OH)D = 25-hydroxyvitamin D; BMI = body mass index; CV = coefficient of variation; DBP = vitamin D–binding protein; iPTH = intact parathyroid hormone; NPHPT = normocalcemic primary hyperparathyroidism     

Vitamin D status and response to Vitamin D(3) in obese vs. non-obese African American children

Background: Serum 25‐hydroxyvitamin D (25(OH)D) is low in obese adults. Objective: To examine serum 25(OH)D in obese (BMI >95th percentile for age) vs. non‐obese (BMI = 5th–75th percentile for age) 6–10‐year‐old African American children and compare their differences in therapeutic response to vitamin D supplementation. Methods and Procedures: In an open label non‐randomized pre‐post comparison 21 obese (OB) and 20 non‐obese (non‐OB) subjects matched for age, sex, skin color, and pubertal maturation were treated with 400 IU of vitamin D₃ daily for 1 month. Serum 25(OH)D, 1,25‐dihydroxyvitamin D (1,25(OH)₂D), parathyroid hormone (PTH), leptin, and markers of bone turnover (serum bone‐specific alkaline phosphatase (BSAP), osteocalcin (OC), and urine n ‐telopeptide cross‐links of type 1 collagen (urine NTX)) were measured. Vitamin D deficiency was defined as serum 25(OH)D ≤20 ng/ml and insufficiency as 21–29 ng/ml respectively. Results: Vitamin D deficiency occurred in 12/21 (57%) OB vs. 8/20 (40%) non‐OB at baseline (P = 0.35) and persisted in 5/21 (24%) OB vs. 2/18 (11%) non‐OB (P = 0.42) after treatment. When the cohort was stratified by the baseline levels of 25(OH)D, there were differences in the response to treatment in the obese and non‐obese cohorts. Discussion: Vitamin D deficiency was common among OB and non‐OB preadolescent African American children, and 400 IU of vitamin D₃ (2× the recommended adequate intake) daily for 1 month was inadequate to raise their blood levels of 25(OH)D to ≥30 ng/ml.     

Parathyroid hormone response to vitamin D insufficiency in elderly males with chronic heart failure

Secondary hyperparathyroidism (SHPT) may contribute to the systemic illness that accompanies chronic heart failure (CHF). Healthy elderly with vitamin D deficiency who did not develop hyperparathyroidism (functional hypoparathyroidism, FHPT) had lower mortality than those who did. This study was designed to examine determinants of the PTH response in the vitamin D insufficient CHF patients. Sixty five vitamin D insufficient males with NYHA class II and III and 20 control subjects age >/=55 years were recruited. Echocardiography, physical performance, NT-pro-BNP, PTH, 25-hydroxyvitamin D (25(OH)D), adiponectin and bone activity surrogate markers (OPG, RANKL, OC, beta-CTx) were assessed. Increased NYHA class was associated with SHPT, while physical performance was inferior compared to FHPT. SHPT was associated with lower left ventricular ejection fraction (LVEF) and flow mediated dilatation, but with higher left heart dimensions, left ventricular mass index and right ventricular systolic pressure. CHF patients with SHPT had increased NT-pro-BNP, adiponectin and bone markers, but decreased 25(OH)D compared to those with FHPT. Independent determinants for SHPT in CHF patients with vitamin D insufficiency were LVEF, adiponectin and beta-CTx, irrespective of renal function and serum vitamin D levels. In conclusion, increased PTH levels, but not low vitamin D, demonstrated close relation to CHF severity.     

Association Between Aldosterone and Parathyroid Hormone Levels in Patients With Adrenocortical Tumors

ObjectivePatients with primary aldosteronism (PA) can present with high PTH levels and negative calcium balance, with some studies speculating that aldosterone could directly stimulate PTH secretion. Either adrenalectomy or mineralocorticoid receptor blockers could reduce PTH levels in patients with PA. The aim of this study was to assess the relationship between aldosterone levels and parathyroid hormone (PTH)-vitamin D-calcium axis in a cohort of patients with PA, compared with patients with nonsecreting adrenocortical tumors in conditions of vitamin D sufficiency.MethodsWe enrolled a series of 243 patients retrospectively, of whom 66 had PA and 177 had nonsecreting adrenal tumors, and selected those with full mineral metabolism evaluation and 25(OH) vitamin D levels >20 ng/mL at the time of initial endocrine screening. The final cohort was composed of 26 patients with PA and 39 patients, used as controls, with nonsecreting adrenal tumors. The relationships between aldosterone, PTH levels, and biochemistries of mineral metabolism were assessed.ResultsAldosterone was positively associated with PTH levels (r = 0.260, P < .05) in the whole cohort and in the PA cohort alone (r = 0.450; P = .02). In the multivariate analysis, both aldosterone concentrations and urinary calcium excretion were significantly related to PTH levels, with no effect of 25(OH) vitamin D or other parameters of bone metabolism.ConclusionPTH level is associated with aldosterone, probably independent of 25(OH) vitamin D levels and urinary calcium. Whether aldosterone interacts directly with the parathyroid glands remains to be established.     

Vitamin D Binding Protein Genotype Is Associated with Serum 25-Hydroxyvitamin D and PTH Concentrations,as Well as Bone Health in Children and Adolescents in Finland

Vitamin D binding protein (DBP)/group-specific component (Gc), correlates positively with serum vitamin D metabolites, and phenotype influences serum 25-hydroxyvitamin D (S-25(OH)D) concentration. The protein isoform has been associated with decreased bone mineral density (BMD) and increased fracture risk. We examined the role of GC genotypes in S-25(OH)D status and BMD in 231 Finnish children and adolescents aged 7−19 yr. BMD was measured with DXA from lumbar spine (LS), total hip, and whole body, and for 175 subjects, radial volumetric BMD was measured with pQCT. Background characteristic and total dietary intakes of vitamin D and calcium were collected. The concentrations of 25(OH)D, parathyroid hormone (PTH), calcium and other markers of calcium homeostasis were determined from blood and urine. Genotyping was based on single-nucleotide polymorphism (rs4588) in the GC gene. The genotype distribution was: GC 1/1 68%, GC 1/2 26% and GC 2/2 6%. A significant difference emerged in 25(OH)D and PTH concentrations between the genotypes, (p = 0.001 and 0.028 respectively, ANCOVA). There was also a linear trend in: Gc 2/2 had the lowest 25(OH)D and PTH concentrations (p = 0.025 and 0.012, respectively). Total hip bone mineral content was associated with GC genotype (BMC) (p = 0.05, ANCOVA) in boys. In regression analysis, after adjusting for relevant covariates, GC genotype was associated with LS BMC and strength and strain index (SSI) Z-score in both genders, and LS BMD in boys. In conclusion, the present study demonstrates the association between GC genotypes and S-25(OH)D and PTH concentrations. The results show the influence of DBP genetic variation on bone mass accrual in adolescence.     

The influence of bariatric surgery on calcium homeostasis and biochemical markers of bone turnover in patients with morbid obesity

INTRODUCTION: Obese patients may have abnormal calcium homeostasis because of unbalanced diet and decreased sun exposure. Bariatric surgery itself may lead to disturbances in calcium homeostasis (and in consequence changes in bone mass) or increase preexisting metabolic derangements. The aim of the study was: 1. To assess calcium homeostasis and biochemical markers of bone turnover in patients with morbid obesity. 2. To determine the impact of bariatric surgery on parameters mentioned above. 3. To establish recommendations for supplementation with calcium and vitamin D in morbidly obese patients after bariatric surgery. MATERIAL AND METHODS: Serum calcium, parathormone (PTH), vitamin D (25(OH)D), biochemical markers of bone turnover (beta-CrossLaps as a marker of bone resorption and osteocalcin as a marker of bone formation) and urine calcium as well as fat mass, lean mass and bone mineral content (by DXA) were measured before bariatric surgery of the stomach (VBG or GBP) in 57 morbidly obese patients (48 women, 9 men; mean age 35.9 y). The same procedures were repeated six months after operation in 28 of them (24 women, 4 men). Daily calcium intake was also determined based on food questionnaire. RESULTS: Biochemical findings in the group of patients before bariatric surgery were as follows: serum calcium, beta-CrossLaps and urine calcium were within normal range, PTH concentration was increased to 81.0 pg/ml and 25(OH)D as well as osteocalcin concentration decreased (4.9 ng/ml and 13.6 ng/ml, respectively). Six months after bariatric surgery there was no change in serum and urine calcium, PTH concentration decreased to normal level (46.8 pg/ml), 25(OH)D concentration increased to 6.5 ng/ml (not significant) and still remained below normal range. Markers of bone turnover--both resorption and formation--increased (beta-CrossLaps over normal range to 0.594 ng/ml, osteocalcin to normal range 26.8 ng/ml). Daily calcium intake was below RDA before and after bariatric procedure. CONCLUSIONS: 1. Patients with morbid obesity have secondary hyperparathyroidism and deficiency of vitamin D. 2. Abrupt weight loss after bariatric surgery is accompanied by the regression of secondary hyperparathyroidism, decrease of the deficiency of vitamin D and increase in bone turnover. 3. Supplementation with vitamin D and calcium is recommended for patients with morbid obesity after bariatric surgery.     

Vitamin d status and its relationship with bone mineral density and parathyroid hormone in southeast asian adults with low bone density

ObjectiveTo investigate the vitamin D sufficiency status and the relationships among serum 25-hydroxyvitamin D [25(OH)D] levels, intact parathyroid hormone (iPTH) levels, and bone mineral density (BMD) in patients attending an osteoporosis clinic in Singapore.MethodsIn total, 193 adults with or without prevalent fragility fractures and with low BMD at the femoral neck, total hip, or lumbar spine underwent assessment. Multivariate regression models were used to investigate the relationships among serum 25(OH)D, iPTH, and BMD.ResultsThe mean values (standard deviation) for age of the patients and serum 25(OH)D level were 61 (14) years and 26.05 (7.97) ng/mL, respectively. In 72% of patients, serum 25(OH)D levels were below 30 ng/mL. There was no association between 25(OH)D levels and BMD at the femoral neck, total hip, or lumbar spine(P = .568, .461, and .312, respectively). Serum iPTH levels were negatively associated with BMD at the total hip(P = .035) and the lumbar spine (P = .019). At levels < 30 ng/mL, 25(OH)D was negatively associated with iPTH (P = .036).ConclusionAmong this Southeast Asian population of patients with low BMD, no direct relationship between serum 25(OH)D levels and BMD was observed. A negative correlation existed, however, between iPTH and 25(OH)D at serum 25(OH)D concentrations < 30 ng/mL, and serum iPTH levels showed a significant negative association with BMD at the total hip and lumbar spine. These significant negative associations between iPTH levels and BMD at the total hip and lumbar spine underscore the critical role of this hormone in bone metabolism and health. (Endocr Pract. 2011;17:226-234)     

Increased PTH and 1.25(OH)(2)D levels associated with increased markers of bone turnover following bariatric surgery

The objective of this study was to characterize changes in metabolic bone parameters following bariatric surgery. Seventy-three obese adult patients who underwent either gastric banding (GB), Roux-en-Y gastric bypass (RYGB), or biliopancreatic diversion with duodenal switch (BPD/DS) were followed prospectively for 18 months postoperatively. Changes in the calcium-vitamin D axis (25-hydroxyvitamin D (25OHD), 1,25-dihydroxyvitamin D (1,25(OH)(2)D), calcium, parathyroid hormone (PTH)), markers of bone formation (osteocalcin, bone-specific alkaline phosphatase) and resorption (urinary N-telopeptide (NTx)), as well as bone mineral density (BMD) were assessed at 3-month intervals during this time period. Bariatric surgery resulted in significant and progressive weight loss over 18 months. With supplementation, 25OHD levels increased 65.3% (P < 0.0001) by 3 months, but leveled off and decreased <30 ng/ml by 18 months. PTH initially decreased 21.4% (P = 0.01) at 3 months, but later approached presurgery levels. 1,25(OH)(2)D increased significantly starting at month 12 (50.3% increase from baseline, P = 0.008), and was positively associated with PTH (r = 0.82, P = 0.0001). When stratified by surgery type, median PTH and 1,25(OH)(2)D levels were higher following combined restrictive and malabsorptive operations (RYGB and BPD/DS) compared to GB. Bone formation/resorption markers were increased by 3 months (P < 0.05) and remained elevated through 18 months. Radial BMD decreased 3.5% by month 18, but this change was not significant (P = 0.23). Our findings show that after transient improvement, preoperative vitamin D insufficiency and secondary hyperparathyroidism persisted following surgery despite supplementation. Postoperative secondary hyperparathyroidism was associated with increased 1,25(OH)(2)D levels and increased bone turnover markers.     

Calcium supplementation increases bone mass in GH-deficient prepubertal children during GH replacement

BACKGROUND/AIMS: Since GH plays an important role in bone mineralization, and several studies demonstrated the positive influence of a higher calcium intake on bone mass, we studied the effect of calcium supplementation in GHD children during GH therapy. METHODS: 28 prepubertal GHD children, 5.0-9.9 years old, were assigned to two groups: group A (n = 14; 7 females) treated with GH, and group B (n = 14; 7 females) treated with GH + calcium gluconolactate and carbonate (1 g calcium/day per os). Auxological parameters, total bone mineral content (TBMC) and density (TBMD), leg BMC and BMD, lumbar BMD, fat mass (FM) and lean tissue mass (LTM), blood 25-hydroxyvitamin D (25-OHD), parathyroid hormone (PTH), osteocalcin (OC) and urinary N-terminal telopeptide of type I collagen (NTx) were determined at the start of therapy and after 1 and 2 years of treatment. RESULTS: During the 2 years of the study, TBMC, TBMD, leg BMC and BMD (but not lumbar BMD) increased in both groups of patients, however after 2 years of treatment they were significantly higher in the calcium-supplemented group B than in group A (p < 0.05, for all parameters). At the start of therapy, in both groups of patients percentage FM was higher and total and leg LTM lower than in controls (p < 0.05 for each parameter). Thereafter, FM decreased and LTM increased and after 2 years they were both different from baseline (p < 0.05). After 2 years of treatment, leg BMC and BMD were more positively correlated with regional leg LTM in patients of group B (r = 0.834 and r = 0.827, respectively; p < 0.001) than in patients of group A (r = 0.617 and r = 0.637, respectively; p < 0.05). 25-OHD and PTH levels were in the normal range in all patients at the start and during treatment. OC levels were lower and urinary NTx levels higher in patients than in controls (p < 0.05 for both parameters), either at the start and after 1 year of treatment. After 2 years of treatment, OC levels were significantly higher than at the start of the study (p < 0.05) in both groups of patients, but they were higher in group B than in group A (p < 0.05); on the contrary, urinary Ntx levels were lower in group B than in group A (p < 0.05). CONCLUSION: In GHD children, treated with GH, calcium supplementation improved bone mass; it may aid in reaching better peak bone mass and in protecting weight-bearing bones, usually completed in childhood to maximum levels, from risk of osteoporosis and fractures later in life.     

The effect of active vitamin D3 analogs and dexamethasone on the expression of osteocalcin gene in rat tibiae in vivo.

We tested the effects of 1 alpha,25-dihydroxyvitamin D3 (1,25-(OH)2D3), 2 beta-(3-hydroxypropoxy)-1 alpha,25-dihydroxyvitamin D3 (ED-71) and dexamethasone on osteocalcin mRNA levels in rat tibiae in vivo. Northern blot analysis showed that both 1,25-(OH)2D3 and ED-71 caused an increase in osteocalcin mRNA levels in bone: 1,25-(OH)2D3 induced a transient increase in the mRNA levels followed by a decrease in the control level by 12 h post administration. In contrast, ED-71 caused a persistent increase in osteocalcin mRNA level for seven days post administration. Serum osteocalcin levels paralleled the osteocalcin mRNA level in bone in both groups. Dexamethasone caused a marked reduction in both osteocalcin mRNA and serum osteocalcin levels. Suppressive effect of dexamethasone on osteocalcin expression was persistent for seven days at higher dose. Our results represent the first demonstration of the effect of active vitamin D and corticosteroid on the expression of osteocalcin mRNA in bone in vivo.     

The Associations Between Hypovitaminosis D,Higher Pth Levels With Bone Mineral Densities,And Risk Of The 10-Year Probability Of Major Osteoporotic Fractures In Chinese Patients With T2Dm

Objective: In the current study, we investigated the vitamin D status, and its relationships with parathyroid hormone (PTH) levels, bone mineral density (BMD), and the 10-year probability of fractures in Chinese patients with type 2 diabetes mellitus (T2DM).Methods: This was a cross-sectional study of 785 patients. BMDs at the lumbar spine (L2-4), femoral neck (FN), and total hip (TH) were measured by dual-energy X-ray absorptiometry (DXA). Serum levels of 25-hydroxyvitamin D (25(OH)D) and intact PTH were also quantified. The 10-year probability of fracture risk (major osteoporotic fracture &lsqb;MOF] and hip fracture &lsqb;HF]) was assessed using the fracture risk assessment tool (FRAX).Results: The prevalence of vitamin D deficiency was 82.3%, and the mean 25(OH)D level was 36.9 ± 15.2 nmol/L. The adequate group had higher BMDs at the FN and TH and lower MOF risk than the inadequate groups. Lower 25(OH)D was associated with higher PTH (r = -0.126, P<.001). PTH was negatively correlated with BMDs at 3 sites and positively correlated with MOF and HF, but this relationship disappeared in the adequate subgroup. Multivariate stepwise regression analysis revealed that PTH was the determinant of MOF (standard β = 0.073, P = .010) and HF (standard β = 0.094, P = .004).Conclusion: Our results identified a significantly high rate of vitamin D deficiency among Chinese patients with T2DM. PTH is an important risk factor responsible for the higher 10-year probability of osteoporotic fractures in diabetic patients, especially in those with lower vitamin D levels.Abbreviations: AKP = alkaline phosphatase; ALB = serum albumin; BMD = bone mineral density; BMI = body mass index; Ca = calcium; CKD = chronic kidney disease; Cr = creatinine; FN = femoral neck; FRAX = fracture risk assessment tool; HbA1c = glycated hemoglobin A1c; HF = hip fracture; L2-4 = lumbar spine; MOF = major osteoporotic fracture; 25(OH)D = 25-hydroxyvitamin D; P = phosphorus; PTH = parathyroid hormone; T2DM = type 2 diabetes mellitus; TH = total hip; UA = uric acid     

Decreased serum levels of 1,25-(OH)2 vitamin D during 1 year of sunlight deprivation in the Antarctic

French Antarctic territories harbor bases that are devoted to scientific and technical work. Living and working conditions during 1-year sojourns in such an environment are quite acceptable, but the confinement and the drop in ultraviolet B radiation exposure during winter months raise the problem of preservation of normal vitamin D status. Seasonal variations in 25-hydroxyvitamin D [25(OH)D] levels have been well documented, but the effect of sunshine deprivation on 1,25 dihydroxyvitamin D [1,25(OH)2D] levels is quite controversial. The aim of this study was to address this question under the exceptional conditions of lack of sunshine exposure. Fifteen male Caucasian subjects participating in a 1-year mission in Antarctica were investigated. They were subjected to seven blood samplings, one before and six during their sojourn. Serum levels of 25(OH)D, 1,25(OH)2D, osteocalcin, and ICTP were measured. We found that levels of 25(OH)D and 1,25(OH)2D significantly decreased in these subjects during the mission, minimum levels being observed 10 months after their departure from France. ICTP concentrations did not change throughout this study, but osteocalcin levels were found to be higher at the end of the sojourn than before departure, which could argue for the existence of bone remodeling changes. Further studies are now needed to fully investigate bone metabolism changes and to address the question of vitamin D supplementation during this kind of sojourn.     

Use of a transjugular intrahepatic portosystemic shunt combined with autologous bone marrow cell infusion in patients with decompensated liver cirrhosis: an exploratory study

Background aimsCurrently, there is no treatment for decompensated liver cirrhosis except for liver transplantation. The safety and effect on liver function of a transjugular intrahepatic portosystemic shunt (TIPS) with and without autologous bone marrow cell (BMC) infusion in patients with decompensated liver cirrhosis were determined.MethodsTen patients who were diagnosed with decompensated liver cirrhosis during the period from September 2011 to July 2012 were enrolled in this study. The patients underwent TIPS (TIPS group) or combined treatment with TIPS and BMC infusion through the hepatic artery (TIPS+BMC group). All patients were monitored for adverse events, liver function and complications caused by portal hypertension during a period of 52 weeks.ResultsThe number of infused BMCs was 2.65 ± 1.20 ×10⁹. Significant improvements in the serum levels of albumin and total bilirubin and decreased Child-Pugh scores were observed in patients treated with both TIPS and BMCs (P < 0.05), whereas no such changes were observed in the TIPS group. Endoscopic findings showed that varices in the esophagus and the gastric fundus were alleviated after either treatment. All 10 patients showed a complete or partial resolution of ascites at 4 weeks. No major adverse effects were noted during the follow-up period for patients in either group.ConclusionsTIPS combined with BMC infusion is clinically safe; the treatment improved liver function and alleviated complications caused by portal hypertension; therefore, this combination has potential for treatment of patients with decompensated liver cirrhosis.     

Effect of cervus and cucumis polypeptide combined with zoledronic acid on bone metabolic biochemical markers in glucocorticoids – Induced osteoporosis patients

ObjectiveTo investigate the effect of cervus and cucumis polypeptide combined with zoledronic acid on bone metabolic biochemical markers in glucocorticoids - induced osteoporosis patients.MethodsA total of 100 patients with glucocorticoids - induced osteoporosis admitted to our hospital from January 2015 to June 2017 were enrolled in this study. Patients were divided into observation group and control group by random number table method, 50 cases in each group. Patients in the observation group were treated with deer melon polypeptide in combination with zoledronic acid, and patients in the control group were treated with zoledronic acid alone. The patients in both groups were treated for 2 months. The changes of bone mineral density (BMD) and biochemical markers of bone metabolism in lumbar vertebrae L1-4, left femoral neck and large trochanter were analyzed before and after treatment.ResultsThe pre- BMD at lumbar spine L_1-4, left femoral neck and great trochanter had no statistic difference (P > 0.05), the BMD at each sites improved after treatment, and the difference were statistical before and after treatment (P < 0.05). BMD at above sites of two groups after treatment had statistical difference (P < 0.05), and the BMD at lumbar spine L_1-4, left femoral neck and great trochanter in the observation group was higher than that of the control group. There were no significant differences in PTH, 25-(OH)D3, TRACP, β-CTX and BGP levels between the two groups before treatment (P > 0.05). The levels of 25-(OH)D3, TRACP, β-CTX and BGP in the two groups were significantly improved after treatment (P < 0.05), and the levels of PTH, TRACP and β-CTX in the observation group were significantly lower than those in the control group. The levels of 25-(OH) D3 and BGP were significantly higher than those of the control group (P < 0.05).ConclusionThe cervus and cucumis polypeptide combined with zoledronic acid can improve the BMD at lumbar spine L_1-4, left femoral neck and great trochanter, and ameliorate the bone metabolic biochemical markers for patients with glucocorticoids - induced osteoporosis.     

Decreased Serum Wnt Antagonist Levels in Patients With Active Acromegaly

ObjectiveThe Wnt signaling pathway is an important modulator of bone metabolism. This study aims to clarify the changes in Wnt antagonists in active and biochemically controlled acromegalic patients.MethodsWe recruited 77 patients recently diagnosed with acromegaly. Of those, 41 patients with complete follow-up data were included. Thirty healthy patients matched for age, sex, and body mass index served as controls. At baseline and posttreatment, Wnt antagonists (sclerostin [SOST], dickkopf-related protein 1 [DKK-1], and Wnt inhibitory factor 1 [WIF-1]), bone turnover markers (osteocalcin, procollagen type 1 N-terminal propeptide [P1NP], and C-terminal telopeptide of type 1 collagen [CTX]) and the bone remodeling index were investigated.ResultsAcromegalic patients had higher serum osteocalcin, P1NP, and CTX and a higher bone remodeling index than controls (P < .01). Serum SOST, DKK-1, and WIF-1 levels were significantly decreased in patients compared to controls (all P < .01). Serum SOST and WIF-1 levels were negatively correlated with growth hormone levels; SOST levels were positively correlated with WIF-1. After treatment, serum bone turnover markers and the bone remodeling index decreased, while SOST and WIF-1 significantly increased (P < .05). DKK-1 levels did not change compared to baseline (P > .05). In biochemically controlled patients, SOST and WIF-1 levels and bone turnover markers were restored and did not differ from those of the control participants (all P > .05).ConclusionPatients with active acromegaly exhibited significantly decreased Wnt antagonist levels. The reduction in Wnt antagonists is a compensatory mechanism to counteract increased bone fragility in active acromegaly.     

Increased Bone Turnover in Type 2 Diabetes Patients Randomized to Bariatric Surgery Versus Medical Therapy at 5 Years

Objective: The aim of our study was to determine the 5-year outcomes of bariatric surgery versus intensive medical therapy on bone turnover in patients with type 2 diabetes mellitus (T2DM) from the STAMPEDE trial.Methods: This was an ancillary investigation of a 5-year randomized control trial at a single tertiary care center involving 95 patients aged 48.5 ± 8 years with obesity (body mass index &lsqb;BMI], 36.5 ± 3.6 kg/m²) and uncontrolled T2DM (glycated hemoglobin 9.3 ± 1.6% &lsqb;78 mmol/mol]). Patients were randomized to intensive medical therapy (IMT; n = 25), Roux-en-Y gastric bypass (RYGB; n = 37), or sleeve gastrectomy (SG; n = 33) for diabetes treatment. Bone formation marker osteocalcin (OC), bone resorption marker serum C-telopeptide of type 1 collagen (CTX), and intact parathyroid hormone (PTH) were assessed at baseline and 5 years postintervention. Analysis with key clinical parameters and outcomes (i.e., age, menopausal status, gender, weight loss) was performed.Results: Percent change in CTX at 5 years increased in both surgical groups, by 137 ± 108% in RYGB (P<.001) and 61.1 ± 90% in SG (P<.001) compared to 29.8 ± 93% in IMT (P = .12). OC also increased from baseline in the surgical cohorts, by 138 ± 19% in RYGB (P<.001) and 71 ± 69% in SG (P<.001) compared to 43.8 ± 121.1% in IMT (P = .83). Increases in both CTX and OC correlated linearly with increases in PTH levels in RYGB patients (P<.001). Increase in CTX correlated with decreased BMI in SG patients (P = .039).Conclusion: In patients with T2DM, bone turnover remains chronically elevated at 5 years following RYGB, and to a lesser extent in SG patients.Abbreviations: BMI = body mass index; BTM = bone turnover marker; CTX = C-telopeptide of type 1 collagen; HbA1c = glycated hemoglobin; IMT = intensive medical therapy; OC = osteocalcin; PPI = proton-pump inhibitor; PTH = parathyroid hormone; RYGB = Roux-en-Y gastric bypass; SG = sleeve gastrectomy; T2DM = type 2 diabetes mellitus; TZD = thiazolidinedione     

Vitamin d, parathyroid hormone and their associations with hypertension in a chinese population

Background

Conflicting reports support or refute an association between vitamin D deficiency with high levels of parathyroid hormone (PTH) and raised blood pressure or hypertension.

Objective

To explore the associations of serum vitamin D and PTH levels with blood pressure and risk of hypertension in a Chinese population.

Methods

A population-based cross-sectional study was conducted among 1,420 Chinese participants, aged 20–83 years, in 2010. Anthropometric phenotypes and blood pressure were evaluated. Serum lipids, 25-hydroxyvitamin D [25(OH)D] and PTH were measured.

Results

One thousand four hundred and twenty participants, including 566 women (39.9%), were evaluated in 2010. Four hundred and eighty seven were hypertensive (34.3%), of whom 214 (43.9%) received antihypertensive treatment. The median concentrations of serum 25(OH)D and PTH were 22.0 ng/ml and 2.83 pmol/l, respectively. Serum 25(OH)D and natural log of PTH levels were not independently associated with blood pressure in a multivariable adjusted linear regression analysis of 1,206 participants not receiving antihypertensive treatment (P>0.05). In logistic regression analyses, serum 25(OH)D levels were not associated with risk of hypertension in single and multiple regression models. One unit increments of natural log of PTH levels were significantly associated with risk of hypertension in the crude model (OR = 1.78, 95% confidence interval 1.38–2.28, P<0.0001) and model adjusted for age and sex (OR = 1.41, 95% confidence interval 1.08–1.83, P = 0.01). However, these associations were attenuated and became nonsignificant (OR = 1.29, 95% confidence interval 0.98–1.70, P = 0.07) after further adjustment for body mass index, current alcohol intake, current smoking, glomerular filtration rate and family history of hypertension.

Conclusions

Serum vitamin D and PTH levels are not independently associated with blood pressure or risk of hypertension in a Chinese population.