Osteocalcin Concentrations Research Articles

The impact of harmful occupational risk factors on the markers of bone metabolism in industrial workers

Introduction. Unfavourable factors of the working environment affect bone tissue, increasing the risk of developing osteoporosis in workers of harmful industries, which is an urgent social and hygienic problem due to the high prevalence and severity of medical and social consequences. The aim of the study was to investigate the impact of industrial vibration and physical overload on the markers of bone metabolism in industrial workers. Materials and methods. One hundred fifty-two employees of mining and mechanical engineering enterprises in contact with industrial vibration and physical overload were examined. The assessment of bone tissue metabolism in the workers was carried out by the method of solid-phase enzyme immunoassay to determine biochemical markers of bone metabolism: bone alkaline phosphatase, osteocalcin, C-terminal serum telopeptide, cathepsin K, as well as indicators of calcium-phosphorus metabolism. X-ray densitometry was used to assess bone mineral density. Results. There was a significant decrease in the markers of osteogenesis: the concentration of CSF (14.26 ± 4.13 and 18.69±5.28, respectively, p< 0.05) and osteocalcin (12.23±4.15 and 17.84±5.17, respectively, p < 0.05) and an increase in the markers of bone resorption: the level of beta-CrossLaps (0.629±0.162 and 0.361±0.095, respectively, p = 0.002) and the level of cathepsin K (12.49±5.28 and 0.59±0.02, respectively, p < 0.001) in workers of industrial enterprises exposed to physical factors of production. The correlation between the markers of bone metabolism and the experience of exposure to adverse working conditions was established. Conclusion. Combined exposure to physical labour factors is a predictor of calcium-phosphorus metabolism and bone metabolism disorders, increasing the risk of metabolic osteopathy in industrial workers.

RELATIONSHIPS BETWEEN OSTEOCALCIN LEVEL AND HORMONAL METABOLIC DISORDERS IN TYPE 2 DIABETIC MEN WITH VARIOUS DEGREES OF OBESITY (LITERATURE REVIEW AND OWN RESEARCH)

The bone hormone osteocalcin is formed by osteoblasts and is partially released into the bloodstream during bone resorption, being a biomarker of bone remodeling. Osteocalcin also plays an important role in the endocrine regulation of metabolic and energy processes in the body and in their coordination. Osteocalcin uses a feedback mechanism to regulate insulin secretion, insulin sensitivity of peripheral tissues, and adipokine levels. In general, the secretion of osteocalcin and insulin are important factors in the formation of hormonal-metabolic phenotype, body composition, determination of regional distribution and metabolic activity of both bone and adipose tissue.The aim of this study was to establish the relationship between osteocalcin concentration and hormonal changes in men with type 2 diabetes with and without obesity on the background of involutive changes. Results. 64 men with type 2 diabetes, older than 50 years, were divided into 2 groups by BMI: 1) non-obese, BMI <30 kg / m2 (n = 31); 2) -obese, BMI ≥ 30 kg / m2 (n = 33). Lower levels of insulin secretion (lower serum C-peptide and insulin levels) were observed in non-obese patients in the absence of a compensatory increase in proinsulin levels. It can be assumed that the increase in the concentration of osteocalcin in group 1 is compensatory, although it does not have a significant effect on blood glucose levels. However, it may have a protective effect on the severity of insulin resistance syndrome and related metabolic disorders. Lower levels of osteocalcin in the obese group were associated with a higher degree of insulin resistance and insulin secretion. There was no significant difference between the two groups in serum proinsulin levels, as well as in androgen supply, which was assessed by the levels of total testosterone, testosteronestradiol-binding globulin, and free testosterone index. Conclusion. Lower levels of osteocalcin may be a marker of an increased risk of adverse metabolic changes in obese patients with type 2 diabetes, followed by complications compared to non-overweight patients

Associations between Sclerostin and Anthropometric and Metabolic Parameters in Children and Adolescents.

(1) Background: Bone plays an important role in the regulation of the systemic glucose and energy metabolism. Sclerostin, secreted by osteocytes, is an inhibitor of the Wnt/β–catenin bone metabolic pathway, and is involved in osteoporosis and metabolic disease. The aim of this study was to investigate the relationship between sclerostin and anthropometric and metabolic parameters in children and adolescents with obesity or who are overweight. (2) Methods: This study included 63 children and adolescents (20 obese, 11 overweight and 32 healthy control subjects). We evaluated the correlation between serum sclerostin and anthropometric parameters, metabolic parameters related to glucose (homeostasis model assessment of insulin resistance [HOMA–IR]), lipid, and bone metabolism (osteocalcin and 25-hydroxy vitamin D). (3) Results: Sclerostin and osteocalcin levels did not differ between obese and control groups. Sclerostin level was higher in boys than in girls (median 20.7 vs. 18.9 pmol/L, respectively; p = 0.04). In all subjects, sclerostin levels were negatively correlated with fasting insulin (r = −0.26; p = 0.04) and HOMA–IR (r = −0.28; p = 0.03), and positively correlated with serum concentrations of triglycerides (r = 0.29; p = 0.04), alkaline phosphatase (r = 0.41; p = 0.002), and osteocalcin (r = 0.33; p = 0.008). In obese patients, sclerostin levels were correlated negatively with fasting glucose (r = −0.49; p = 0.03) and HOMA–IR (r = −0.48; p = 0.03) and positively correlated with triglyceride levels (r = 0.53; p = 0.02). In the healthy control, sclerostin levels were correlated negatively with fasting insulin levels (r = −0.61; p < 0.001) and HOMA–IR (r = −0.36; p = 0.04). After adjusting for age, sex, and height SDS, a negative correlation between sclerostin and HOMA–IR was found (r = −0.39; p = 0.003) in all of the subjects. This association was more evident in obese patients (r = −0.60; p = 0.01) than in healthy controls (r = −0.39; p = 0.047). (4) Conclusions: Among children and adolescents with obesity, serum sclerostin was negatively correlated with HOMA–IR. Further studies are needed to clarify the mechanisms involved to understand how sclerostin affects the glucose metabolism.

Between-subject and within-subject variability in measures of biochemical markers of bone turnover in cynomolgus and rhesus macaques

Development of optimal bone mass during early adulthood is determined by the balance between bone formation and resorption. The utility of minimally invasive biomarkers for monitoring bone turnover balance in maturing non-human primates has received limited attention. This study evaluated the biological variation of osteocalcin (a marker of bone formation), carboxyterminal cross-linking telopeptide of type 1 collagen (CTX, a marker of bone resorption), and the ratio of osteocalcin to CTX (reflecting bone turnover balance), in 136 rhesus and cynomolgus macaques aged 3.8–11.6 years. In a subsample of the animals (n = 28), blood samples were collected at monthly intervals over 4 months. Between-subject analysis revealed that there were no sex or species differences for CTX. Osteocalcin and the ratio of osteocalcin to CTX were higher in males than in females, and in rhesus macaques than in cynomolgus macaques. There were no changes in osteocalcin, CTX, or the ratio of osteocalcin to CTX across 4 months for any of the groups. In contrast, there was considerable within-subject variation in osteocalcin and CTX concentrations. However, differences in values exhibited no discernible pattern, suggesting that within-subject variation can be reduced by averaging repeat measurements. In summary, the data provide reference values for male and female rhesus and cynomolgus macaques and support the utility of osteocalcin and CTX as biomarkers to monitor bone turnover at the population level.

Calcification markers and long-term outcomes of coronary artery bypass grafting

Aim. To assess the long-term outcomes of coronary artery bypass grafting (CABG) and their association with calcification biomarkers.Material and methods. The study included 129 men (mean age, 61,5±7,5 years) with coronary atherosclerosis who were admitted for CABG surgery. Patients were divided into 2 groups: with favorable and unfavorable (death, myocardial infarction, stroke, surgery) 5-year prognosis after surgery. Before the surgery, the blood concentrations of calcification biomarkers (osteoprotegerin, osteopontin, osteonectin and osteocalcin) were determined in all patients.Results. Long-term outcomes of myocardial revascularization were studied in 92 patients (71%). An unfavorable long-term 5-year period was identified in 28 men (30,4%). In men with an unfavorable 5-year prognosis, the blood osteocalcin level before CABG was 1,2 times higher than in men with a favorable one. Multivariate linear regression showed that the risk of a 5-year unfavorable prognosis for coronary atherosclerosis after myocardial revascularization was associated with the blood osteocalcin concentration, determined before CABG (B=0,018, R2=0,285, p=0,008).Conclusion. The data obtained indicate the relevance of continuing studies on osteocalcin, including with respect to its contribution to coronary atherosclerosis and calcification.

Кальцитонин, остеокальцин и остеопонтин при раке легкого

Актуальность. Маркерами рака легкого являются низкие уровни в крови гормона кальцитонина, а высокие показатели белков остеокальцина и остеопонтина, связанные между собой, отражают процессы костного метастазирования и обладают прогностической значимостью. Цель исследования: оценить уровни в крови кальцитонина, остеокальцина и остеопонтина, факторы, их определяющие, характер взаимосвязей и прогностическую роль в костном метастазировании при разных вариантах течения рака легкого. Материалы и методы. Обследованы 86 больных раком легкого в возрасте от 24 до 80 лет (в среднем 58 лет), среди которых было 84 % мужчин и 16 % женщин. Центральная форма рака имела место в 81 % наблюдений, периферическая — в 19 %. Мелкоклеточный гистологический вариант заболевания установлен у 21 % от числа больных, немелкоклеточный — у 79 %, в том числе аденокарцинома — у 38 %, плоскоклеточная карцинома — у 35 %, крупноклеточная карцинома — у 6 %. IIIA стадия опухолевого процесса отмечена в 12 % случаев, IIIB — в 21 %, IV — в 67 %. Результаты. Рак легкого сопровождается уменьшением в крови у 20 % больных остеоассоциированного гормона кальцитонина на фоне повышения концентраций опухолевых маркеров остеокальцина и остеопонтина (соответственно в 76 и 79 % наблюдений), что тесно связано с морфологическим вариантом (мелко- и немелкоклеточный), стадийностью и тяжестью течения патологического процесса, определяет развитие компрессионного синдрома, прорастание опухоли в грудную стенку, метастазирование в лимфатические узлы и кости, возникновение осложнений химиорадиотерапии в виде лучевого пневмофиброза, легочной гипертензии и миелодепрессии, а показатели остеокальцин- и остеопонтинемии обратно коррелируют с продолжительностью жизни больных. Выводы: кальцитонин, остеокальцин и остеопонтин при раке легкого являются маркерами тяжести течения заболевания, отражают метастазирование опухолевого процесса в скелет и обладают прогностической значимостью.

Deficiency of PPARγ in Bone Marrow Stromal Cells Does not Prevent High-Fat Diet-Induced Bone Deterioration in Mice

BackgroundBone marrow osteoblasts and adipocytes are derived from a common mesenchymal stem cell and have a reciprocal relationship. Peroxisome proliferator-activated receptor gamma (PPARγ), a regulator for adipocyte differentiation, may be a potential target for reducing obesity and increasing bone mass. ObjectivesThis study tested the hypothesis that bone-specific Pparg conditional knockout (cKO), via deletion of Pparg from bone marrow stromal cells (BMSC) using Osterix 1 (Osx1)-Cre, would prevent high-fat (HF) diet–induced bone deterioration in mice. MethodsPPARγ cKO (PPARγfl/fl: Osx1-Cre) and floxed littermate control (PPARγfl/fl Osx1-Cre–) mice that were 6 weeks old were randomly assigned to 4 groups (n = 12/group, 6 male and 6 female) and fed ad libitum with either a normal-fat (NF) purified diet (3.85 kcal/g; 10% energy as fat) or an HF diet (4.73 kcal/g; 45% energy as fat) for 6 mo. Bone structure, body composition, and serum bone-related cytokines were measured. Data were analyzed by 2-way ANOVA with Tukey post hoc comparison. ResultsThe HF diet decreased the tibial and lumbar vertebrae trabecular bone volume/total volume (BV/TV) by 28% and 18%, respectively, compared to the NF diet (P < 0.01). PPARγ cKO mice had 23% lower body fat mass and 9% lower lean mass than control mice. PPARγ cKO mice had 41% greater tibial trabecular BV/TV compared to control mice. None of trabecular bone parameters at the second lumbar vertebra were affected by genotype. PPARγ cKO mice had decreased cortical thickness compared to control mice. PPARγ cKO mice had a 14% lower (P < 0.01) serum concentration of leptin and a 35% higher (P < 0.05) concentration of osteocalcin compared with control mice. ConclusionsThese data indicate that PPARγ has site-specific impacts on bone structures in mice and that knockout PPARγ in BMSC increased bone mass (BV/TV) in the tibia but not the lumbar vertebrae. PPARγ disruption in BMSC did not prevent HF diet–induced bone deterioration in mice.

Kidney Function-Dependence of Vitamin K-Status Parameters: Results from the TransplantLines Biobank and Cohort Studies.

High circulating dephosphorylated (dp) uncarboxylated (uc) matrix Gla protein (MGP) and uc osteocalcin (OC) concentrations are regarded as markers of vitamin K-deficiency. However, because MGP and OC are small molecules, they may potentially pass the glomerulus, and their blood concentrations may strongly depend on kidney function. However, many studies with vitamin K-status parameters do not structurally adjust for baseline kidney function, and detailed studies on kidney function-dependence of vitamin K-status markers are lacking. We therefore measured plasma dp-ucMGP using a chemiluminescent assay in 578 kidney transplant recipients (41% females, age 56 ± 13y, 7.5 (3.2 to 13.7)y after transplantation, eGFR 49 ± 17 mL/min/1.73 m2) participating in the prospective TransplantLines Cohort Studies. Additionally, dp-carboxylated MGP, ucOC and carboxylated OC were measured using ELISA in plasma of a subgroup of 60 participants. Finally, dp-ucMGP was measured in a separate cohort of 124 kidney transplant recipients before and three months after kidney transplantation. Dp-ucMGP positively correlated with creatinine, cystatin C, and negatively with eGFR (Spearman’s ρ 0.54, 0.60, and −0.54, respectively, p < 0.001 for all), and each 10 mL/min/1.73 m2 increase in eGFR was associated with a 14.0% lower dp-ucMGP. Additionally, dp-ucMGP strongly declined after kidney transplantation (pretransplantation: 1252 (868 to 1744) pmol/L to posttransplantation: 609 (451 to 914) pmol/L, p < 0.001). Proportions of dp-ucMGP over total MGP and ucOC over total OC were not associated with eGFR. This study highlights that dp-ucMGP is strongly associated with kidney function, and that levels strongly decrease after kidney transplantation. We therefore propose adequate adjustment for kidney function, or the use of kidney function-independent parameters such as proportion of uncarboxylated MGP or OC in the assessment of vitamin K-status in clinical practice and research.

The Role of the Trabecular Bone Score in the Assessment of Osteoarticular Disorders in Patients with HFE-Hemochromatosis: A Single-Center Study from Poland.

Type 1 hereditary hemochromatosis (HH) is an autosomal, recessive genetic entity with systemic iron overload. Iron homeostasis disorders develop as a result of HFE gene mutations, which are associated with hepcidin arthropathy or osteoporosis and may cause permanent disability in HH patients despite a properly conducted treatment with phlebotomies. In this study, selected parameters of calcium and phosphate metabolism were analyzed in combination with the assessment of bone mineral density (BMD) disorders in patients from northern Poland with clinically overt HFE-HH. BMD was determined by a dual-energy X-ray absorptiometry (DXA) test with the use of the trabecular bone score (TBS) function. The study included 29 HH patients (mean age = 53.14 years) who were compared with 20 healthy volunteers. A significantly lower TBS parameter and serum 25-OH-D3 concentration, a higher concentration of intact parathormone and more a frequent occurrence of joint pain were found in HH patients compared with the control group. In HH patients, the diagnosis of liver cirrhosis was associated with lower serum 25-OH-D3 and osteocalcin concentrations. In HH, DXA with the TBS option is a valuable tool in the early assessment of the bone microarchitecture and fracture risk. A supplementation of vitamin D, monitoring its concentration, should be considered especially in HH patients with liver damage and liver cirrhosis.

Beneficial Effect of Successful Simultaneous Pancreas-Kidney Transplantation on Plasma Profile of Metalloproteinases in Type 1 Diabetes Mellitus Patients.

It is not fully elucidated whether the restoring of normal glucose metabolism after successful simultaneous pancreas-kidney transplantation (SPK) improves vascular wall morphology and function in type 1 diabetic (T1D) patients. Therefore, we compared arterial stiffness, assessed by pulse wave velocity (PWV), carotid intima-media thickness (IMT), and biomarkers of arterial wall calcification in T1D patients after SPK or kidney transplantation alone (KTA). In 39 SPK and 39 KTA adult patients of similar age, PWV, IMT, circulating matrix metalloproteinases (MMPs) and calcification biomarkers were assessed at median 83 months post transplantation. Additionally, carotid plaques were visualized and semi-qualitatively classified. Although PWV and IMT values were similar, the occurrence of atherosclerotic plaques (51.3 vs. 70.3%, p < 0.01) and calcified lesions (35.9 vs. 64.9%, p < 0.05) was lower in SPK patients. There were significantly lower concentrations of MMP-1, MMP-2, MMP-3, and osteocalcin in SPK subjects. Among the analyzed biomarkers, only logMMP-1, logMMP-2, and logMMP-3 concentrations were associated with log HbA1c. Multivariate stepwise backward regression analysis revealed that MMP-1 and MMP-3 variability were explained only by log HbA1c. Normal glucose metabolism achieved by SPK is followed by the favorable profile of circulating matrix metalloproteinases, which may reflect the vasoprotective effect of pancreas transplantation.

The Associations of Serum Osteocalcin and Cortisol Levels With the Psychological Performance in Primary Hyperparathyroidism Patients.

ObjectivesThe aim of this study was to investigate factors responsible for the psychological performance in primary hyperparathyroidism (PHPT) patients.MethodsA group of 38 PHPT patients receiving questionnaires, including Beck Depression Inventory (BDI), State–Trait Anxiety Inventory (STAI), and 36-Item Short Form Survey (SF-36), was evaluated. The relationships between scores of questionnaires and clinical biomarkers were examined. Collinearity and linear regression model were applied to examine variables determining the scores of the questionnaire. In 192 PHPT patients, bivariate and partial correlation were used to analyze the relationships between serum concentrations of parathyroid hormone (PTH), calcium, osteocalcin (OCN), and cortisol.ResultsAmong 38 patients receiving questionnaire tests, 50% (19/38) of the patients developed state anxiety, 60.5% (23/38) of the patients had the trait of developing anxiety. In addition, 18.4% (7/38) of the patients developed mild to severe depression. Serum cortisol at 8:00 was negatively and significantly correlated with social function (r = -0.389, p = 0.041) after controlling for age, sex, disease duration, serum PTH, calcium, phosphorus, and 25-hydroxyvitamin D [25(OH)D] concentration. OCN was significantly and negatively correlated with score of STAI-S (r = -0.426, p = 0.027). In the linear regression model for BDI score, variables with statistical significance were serum OCN (β = -0.422, p = 0.019) and cortisol at 0:00 (β = 0.371, p = 0.037). In 192 PHPT patients, the serum concentration of OCN (r = 0.373, p = 0.000) was positively correlated with PTH level. After controlling for age, sex, disease duration, serum 25(OH)D, phosphorus, and calcium concentration, the positive correlation between OCN and PTH was still statistically significant (r = 0.323, p = 0.000). The serum concentration of cortisol at 0:00 was significantly and positively correlated with serum calcium (r = 0.246, p = 0.001) in bivariate correlation analysis. After controlling for age, sex, disease duration, serum PTH, 25(OH)D, and phosphorus concentration, serum cortisol at 0:00 was still positively and significantly correlated with serum calcium (r = 0.245, p = 0.001).ConclusionSerum levels of OCN and cortisol, rather than PTH and calcium, are associated with the development of anxiety and depression symptoms in PHPT patients.

Silicate/zinc-substituted strontium apatite coating improves the osteoinductive properties of \u03b2-tricalcium phosphate bone graft substitute

Backgroundβ-Tricalcium phosphate (β-TCP) is a popular synthetic bone graft substitute with excellent osteoconductive properties and bioabsorbability. However, its osteoinductive properties are inferior to those of autologous or allogeneic bone. Trace elements such as strontium (Sr), silica (Si), and zinc (Zn) have been reported to promote osteogenesis in materials. In this study, we aimed to determine whether a Si/Zn-substituted Sr apatite coating of β-TCP could enhance osteoinductive properties.MethodsThe apatite-coated β-TCP disks were prepared using nanoparticle suspensions of silicate-substituted Sr apatite (SrSiP) or silicate- and Zn-co-substituted Sr apatite (SrZnSiP).Bone marrow mesenchymal cells (BMSCs) from rat femur were cultured and subsequently seeded at a density of 1.0 × 106/cm2 onto apatite-coated and non-coated β-TCP disks.In vitro, the β-TCP disks were then placed in osteogenic medium, and lactate dehydrogenase (LDH) activity was measured from supernatants after culture for 2 days. Additionally, after culture for 14 days, the mRNA expression of genes encoding osteocalcin (OC), alkaline phosphatase (ALP), bone morphogenetic protein-2 (BMP-2), and vascular endothelial growth factor (VEGF) was evaluated by qRT-PCR. In vivo, the β-TCP disks were transplanted subcutaneously into rats that were sacrificed after 4 weeks. Then, the harvested disks were evaluated biochemically (ALP activity, OC content, mRNA expression of OC, ALP, BMP-2, and VEGF measured by qRT-PCR), radiologically, and histologically.ResultsSignificantly higher mRNA expression of almost all evaluated osteogenic and angiogenic genes was observed in the SrZnSiP and SrSiP groups than in the non-coated group, with no significant cytotoxicity elicited by the apatite coating in vitro. Moreover, in vivo, the SrZnSiP and SrSiP groups showed significantly higher osteogenic and angiogenic gene expression and higher ALP activity and OC content than the non-coated group (P < 0.05). Radiological and histopathological findings revealed abundant bone formation in the apatite-coated group.ConclusionsOur findings indicate that apatite coating of β-TCP improves osteoinductive properties without inducing significant cytotoxicity.

Effects of phytase and 25-hydroxyvitamin D3 supplementation on growth performance and bone development in weaned piglets in Ca- and P-deficient dietary.

The beneficial function of phytase and 25-hydroxyvitamin D3 (HyD) on the feed utilization rate has been widely investigated. However, studies concerning its influence on weaned piglets largely lag behind. The aim of this study was to investigate the effects of phytase and HyD supplementation on the growth performance and bone development in weaned piglets under dietary Ca and P deficiency. The results showed that dietary Ca and P deficiency decreased (P < 0.05) the content of serum P in 6-10 kg piglets, as well as reducing (P < 0.05) the contents of serum Ca and P, average daily gain (ADG), bone mineral density (BMD), breaking force (BF), bone ash and femur Ca in 10-20 kg piglets. Compared with the control group, the feed-to-gain ratio (F/G) of 6-10 kg piglets in the Phy group was decreased (P< 0.05), whereas the ADG, blood Ca and P, BMD, BF, bone ash, P apparent digestibility, Ca and P retention rate of 10-20 kg piglets were increased (P < 0.05). The contents of serum osteocalcin and HyD in 6-10 kg piglets and ADG were higher than in the control group (P < 0.05), as well as the contents of serum Ca and HyD in 10-20 kg piglets in the HyD treatment group. Supplementation with both Phy and HyD decreased the F/D (P < 0.05) and increased the contents of serum Ca, P and HyD in 6-10 kg piglets as well as enhancing the ADG, BMD, BF, bone ash, femur Ca and P, serum Ca and P, HyD, and the apparent digestibility and retention of Ca and P (P < 0.05) in 10-20 kg piglets. Supplementation with Phy and HyD in Ca- and P-deficient dietary decreased bone resorption, and improved tight arrangement of collagen fibers and oblique fibers in weaned piglets. These data indicated that supplementation with both 1500 U kg-1 Phy and 50 μg kg-1 HyD could enhance dietary Ca and P utilization and promote bone development in low Ca and P dietary, and supplementation with both Phy and HyD had a significant synergy effect compared to single supplement. © 2021 Society of Chemical Industry.

Anti-osteoporosis effect of Notopterygium incisum Ting ex H. T. Chang extract in rats

Purpose: To investigate the effect of Notopterygium incisum Ting ex H.T. Chang extract (NICE) on ovariectomy-induced osteoporosis in rats.&#x0D; Methods: Female Sprague-Dawley rats were randomly assigned to a normal group (control) and five ovariectomy (OVX) subgroups: OVX with vehicle (OVX), OVX with positive control drug alendronate sodium tablets (1.8 mg/kg/week), and OVX with varying NICE doses (45, 90, or 180 mg/kg/day). After rats were subjected to ovariectomy for 4 weeks, alendronate or NICE were administered orally daily for 16 weeks. The bone mineral density (BMD) of the L4 vertebrae and right femurs of all rats was estimated. The serum hormones estradiol (E2), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels and serum alkaline phosphatase (ALP), osteocalcin (OC) and telopeptides of collagen type I (CTx) levels of rats were detrmined.&#x0D; Results: The results show that NICE dose-dependently inhibited bone mineral density (BMD) reduction of L4 vertebrae and femurs (p &lt; 0.05). Compared with OVX group, serum E2, FSH and LH levels was significantly increased in osteoporosis rats (p &lt; 0.01), but serum ALP, CTx, and OC concentrations were significantly lower (p &lt; 0.05). On the other hand, bone trabeculae in the three NICE groups and nilestriol group were all wider, while the space and connections increased.&#x0D; Conclusion: These findings indicate that NICE mitigates OVX-induced osteoporosis in rats, and hence can potentially be developed for the management of osteoporosis.

Impact of metabolic syndrome and its components on bone remodeling in adolescents.

Osteoporosis and metabolic syndrome (MetS) are diseases that have serious public health consequences, reducing the quality of life of patients and increasing morbidity and mortality, with substantial healthcare expenditures. To evaluate the impact of MetS on bone mineral density (BMD) and biochemical markers of bone formation and resorption in adolescents with excess weight. A descriptive and analytical cross-sectional study was performed that evaluated 271 adolescents of both sexes (10 to 16 years). From the total sample, 42 adolescents with excess weight and the presence of MetS (14%) were selected. A further 42 adolescents with excess weight and without MetS were chosen, matched for chronological age, bone age, and pubertal developmental criteria to those with MetS, for each sex. Anthropometric measurements, blood pressure collection, and biochemical tests were performed in all adolescents, as well as evaluation of BMD and the bone biomarkers osteocalcin (OC), bone alkaline phosphatase (BAP), and carboxy-terminal telopeptide (S-CTx). The adolescents with excess weight and MetS exhibited significantly lower transformed BMD and concentrations of BAP, OC, and S-CTx compared to the matched group, except for OC in boys. A negative and significant correlation was observed between total body BMD and BAP (r = -0.55568; p = 0.005), OC (r = -0.81760; p = < .000), and S-CTx (r = -0.53838; p = 0.011) in girls. Metabolic syndrome may be associated with reduced bone mineral density and biochemical markers of bone formation and resorption in adolescents with excess weight.

New insights into the metabolic-bone crosstalk in active acromegaly.

Body composition (BC) and adipokines share bone active properties and display an altered profile in acromegaly. The fibroblast growth factor 23 (FGF23)/α-Klotho system, also involved in bone metabolism, is upregulated in growth hormone (GH) excess states. Hence, we aimed to investigate their impact on bone in active acromegaly, compared to controls. BC, bone mineral density (BMD) (via dual X-ray absorptiometry), serum adipokines (leptin, adiponectin, resistin), parathyroid hormone (PTH), FGF23, α-Klotho, and osteocalcin were assessed in a cross-sectional study enrolling 35 patients with active acromegaly (Acro), compared to 35 sex, age, and body mass index (BMI) one-to-one matched healthy controls (CTL). The Acro group had higher bone density scores (p < 0.05), lower visceral fat depots (p = 0.011), and lower serum leptin (p < 0.001) but elevated adiponectin (p < 0.001) and resistin (p = 0.001) concentrations when compared to the CTL group. α-Klotho was not related to the GH/IGF1 axis in the Acro group. Resistin was higher in both diabetic and non-diabetic Acro compared to CTL (p < 0.05). Age and BC were the main independent BMD predictors in regression analysis in both groups, while IGF1 was a positive predictor of osteocalcin levels in the Acro (β = 0.48, p = 0.006). The correlations between adipokines, the FGF23/α-Klotho system, and bone parameters, respectively, were lost after adjusting for age and BC. Age and BC were the main independent BMD predictors in the acromegalic patients with active disease, while IGF1 was independently associated with serum osteocalcin concentrations. The role of α-Klotho in evaluating acromegaly and the associated osteopathy in the long-term appears to be limited. Our study is among the first to report significant serum resistin changes in patients with active acromegaly, opening new insights in the GH-mediated insulin resistance. The GH-resistin relationship merits further investigations.

Unilateral cervical spinal cord injury induces bone loss and metabolic changes in non-human primates (Macaca fascicularis).

Background/ObjectiveThe deleterious effects of chronic spinal cord injury (SCI) on the skeleton in rats, especially the lower extremities, has been proved previously. However, the long-term skeletal changes after SCI in non-human primates (NHP) have been scarcely studied. This study aimed to evaluate the bone loss in limbs and vertebrae and the bone metabolic changes in NHP after unilateral cervical spinal cord contusion injury.MethodsTwelve Macaca fascicularis were randomly divided into the SCI (n=8) and the Sham (n=4) groups. The SCI models were established using hemi-contusion cervical spinal cord injury on fifth cervical vertebra (C5), and were further evaluated by histological staining and neurophysiological monitoring. Changes of bone microstructures, bone biomechanics, and bone metabolism markers were assessed by micro-CT, micro-FEA and serological kit.ResultsThe NHP hemi-contusion cervical SCI model led to consistent unilateral limb dysfunction and potential plasticity in the face of loss of spinal cord. Furthermore, the cancellous bone mass of ipsilateral humerus and radius decreased significantly compared to the contralateral side. The bone volume fraction of humerus and radius were 17.2% and 20.1% on the ipsilateral while 29.0% and 30.1% on the contralateral respectively. Similarly, the thickness of the cortical bone in the ipsilateral forelimbs was significantly decreased, as well as the bone strength of the ipsilateral forelimbs. These changes were accompanied by diminished concentration of osteocalcin and total procollagen type 1 N-terminal propeptide (t-P1NP) as well as increased level of β-C-terminal cross-linking telopeptide of type 1collagen (β-CTX) in serological testing.ConclusionsThe present study demonstrated that hemi-SCI induced loss of bone mass and compromised biomechanical performance in ipsilateral forelimbs, which could be indicated by both muscle atrophy and serological changes of bone metabolism, and associated with a consistent loss of large-diameter cells of sensory neurons in the dorsal root ganglia.The Translational potential of this ArticleOur study, for the first time, demonstrated the bone loss in limbs and vertebrae as well as the bone metabolic changes in non-human primates after unilateral spinal cord injury (SCI). This may help to elucidate the role of muscle atrophy, serological changes and loss of sensory neurons in the mechanisms of SCI-induced osteoporosis, which would be definitely better compared with rodent models.

Deficiency of PPAR Gamma in Bone Marrow Stromal Cells Does Not Prevent High-Fat Diet-Induced Bone Deterioration in Mice

ObjectivesObesity is detrimental to bone health in humans and in high-fat diet-induced obese animals. Bone marrow osteoblasts and adipocytes are derived from a common mesenchymal stem cell and have a reciprocal relationship. Peroxisome proliferator-activated receptor gamma (PPAR gamma), a regulator for adipocyte differentiation, may be a potential target for reducing obesity and increasing bone mass. This study tested the hypothesis that bone-specific PPAR gamma conditional knockout (cKO), via deletion of PPAR gamma gene from bone marrow stromal cells (BMSC) using Osterix 1 (Osx1)-Cre, would prevent high-fat diet-induced bone deterioration in mice. MethodsPPAR gamma cKO (PPAR gammafl/fl: Osx1–Cre) and floxed littermate control (PPAR gammafl/fl Osx1-P-Cre-) mice at 6-wk-old were randomly assigned to 4 groups (n = 12/group, 6 male and 6 female) and fed ad libitum either a normal-fat purified diet (NF, 3.85 kcal/g, 10% energy as fat) or a high-fat diet (HF, 4.73 kcal/g) for 6 mo. Bone structure, body composition, and serum bone-related cytokines were measured. ResultsCompared to the NF diet, the HF diet increased body mass and fat mass (P < 0.05) but not lean mass. The HF diet also decreased tibial and lumbar vertebrae trabecular volume/total volume (BV/TV) and bone mineral density (BMD) in both control and PPAR gamma cKO mice. PPAR gamma cKO mice had lower body fat mass and lean mass than control mice. PPAR gamma cKO mice had greater tibial trabecular BV/TV, trabecular number, connectivity density, and BMD and lower structure model index, compared to control mice. None of trabecular bone parameters at 2nd lumbar vertebrae was affected by genotype. PPAR gamma cKO mice had lower cortical medullary area, compared to control mice. PPAR gamma cKO mice had lower (P < 0.01) serum concentration of leptin and higher (P < 0.05) concentration of osteocalcin, compared with control mice. ConclusionsThese data indicate that PPAR gamma has site-specific impact on bone structure in mice and that knockout PPAR gamma in BMSC increased bone mass in tibia likely through increased osteoblastogenesis. However, PPAR gamma disruption in BMSC did not prevent high-fat diet-induced bone deterioration in mice. Funding SourcesUSDA-ARS #3062-51,000-053-00D.

Circulating Osteoprotegerin in Chronic Kidney Disease and All-Cause Mortality.

BackgroundChronic kidney disease (CKD) is associated with cardiovascular disease (CKD), mineral and bone disorder (CKD-MBD) and high mortality. Bone-related factors such as osteopontin (OPN), osteocalcin (OC), osteoprotegerin (OPG) and fibroblast growth factor 23 (FGF23) were linked to cardiovascular complications of CKD and are expected to have predictive value in CKD patients.PurposeThe aim of this study was to assess the relationship of OPN, OC, OPG and FGF23 to clinical characteristics and to evaluate their ability to predict mortality in patients with different CKD stages.MethodsThe following study groups were enrolled: subjects with end-stage renal disease (38 ESRD), CKD stages 3 and 4 (19 CKD3-4) and non-CKD controls (19), respectively. Blood was withdrawn once to perform the measurements and cardiac computed tomography was used to evaluate coronary calcium score (CS). Patients were followed for 5 years for the ascertainment of their all-cause mortality.ResultsSerum OPN, OC and OPG concentrations increased significantly along with the progression of renal disease. We found a significant positive correlation among these proteins. Additionally, OPN and OPG were significantly and positively correlated to CS. Serum OPG revealed the strongest correlation to the calcium turnover markers of GFR decline and was significantly associated with an increased risk of death in subjects with CKD3-4 or ESRD (HR 5.8, CI 95%).ConclusionSingle measurement of osteoprotegerin is associated with 5-year all-cause mortality in patients with CKD3-4 or ESRD. We suggest assessing its concentration, preferably in combination with calcium score, to stratify mortality risks in CKD patients.

Effect of Eight Weeks of Aerobic Interval Training on the Serum Concentrations of Alkaline Phosphatase, Osteocalcin and Parathyroid Hormone in Middle-aged Men

Background: Osteoporosis is the most common disorder of bone and mineral metabolism. This disease is associated with decreased bone density and loss of bone microstructure, leading to increased fragility and risk of bone fractures. Objectives: The aim of this study was to evaluate the effect of eight weeks of aerobic interval training on the serum concentrations of alkaline phosphatase, osteocalcin, and parathyroid hormone in middle-aged men. Methods: This was a quasi-experimental study of 24 men, who were divided into two groups of control (n = 12) and aerobic interval training (n = 12). Training performed during eight weeks, three times a week, each session for 45 to 60 minutes. Blood samples were analyzed for the concentrations of calcium, phosphorus, alkaline phosphatase, osteocalcin, and parathyroid hormone before and after completion of the training program. Paired samples t-test and analysis of covariance (ANCOVA) were run to analyze the data (P ≤ 0.05). Results: Weight and body mass index decreased significantly, and the maximum oxygen consumption at the end of the training program increased significantly in the experimental group. Eight weeks of aerobic exercise led to a significant increase in the amounts of calcium (P = 0.001), phosphorus (P = 0.001), alkaline phosphatase (P = 0.001), osteocalcin (P = 0.001), and parathyroid hormone (P = 0.001) in the experimental group. Conclusions: It can be stated that eight weeks of aerobic interval training may be effective in preventing osteoporosis by reducing body composition indices and increasing calcium, phosphorus, alkaline phosphatase, osteocalcin, and serum parathyroid hormone in inactive men.