Environmental Factors That Affect Parathyroid Hormone and Calcitonin Levels

Calciotropic hormones, parathyroid hormone (PTH) and calcitonin are involved in the regulation of bone mineral metabolism and maintenance of calcium and phosphate homeostasis in the body. Therefore, an understanding of environmental and genetic factors influencing PTH and calcitonin levels is crucial. Genetic factors are estimated to account for 60% of variations in PTH levels, while the genetic background of interindividual calcitonin variations has not yet been studied. In this review, we analyzed the literature discussing the influence of environmental factors (lifestyle factors and pollutants) on PTH and calcitonin levels. Among lifestyle factors, smoking, body mass index (BMI), diet, alcohol, and exercise were analyzed; among pollutants, heavy metals and chemicals were analyzed. Lifestyle factors that showed the clearest association with PTH levels were smoking, BMI, exercise, and micronutrients taken from the diet (vitamin D and calcium). Smoking, vitamin D, and calcium intake led to a decrease in PTH levels, while higher BMI and exercise led to an increase in PTH levels. In terms of pollutants, exposure to cadmium led to a decrease in PTH levels, while exposure to lead increased PTH levels. Several studies have investigated the effect of chemicals on PTH levels in humans. Compared to PTH studies, a smaller number of studies analyzed the influence of environmental factors on calcitonin levels, which gives great variability in results. Only a few studies have analyzed the influence of pollutants on calcitonin levels in humans. The lifestyle factor with the clearest relationship with calcitonin was smoking (smokers had increased calcitonin levels). Given the importance of PTH and calcitonin in maintaining calcium and phosphate homeostasis and bone mineral metabolism, additional studies on the influence of environmental factors that could affect PTH and calcitonin levels are crucial.

Bone Health in School Age Children: Effects of Nutritional Intake on Outcomes

The maximum rate of bone mass accumulation is during early adolescence. As such, a focus on optimizing mineral nutrition in school age children, defined here as approximately 5 to 15 years of age, is crucial to minimize the risk of bone loss that occurs later in life leading to osteoporosis and fractures. Optimizing bone mass in this age group requires attention to an overall healthy diet including adequate calcium, phosphorus, magnesium, and vitamin D. Special concerns may exist related to children who follow a restricted diet such as a vegan diet, those with intolerance or allergies to dairy, and those with chronic health conditions including young adolescents with eating disorders. Public policy messages should focus on positive aspects of bone health nutrition in this age group and avoid overly specific statements about the exact amounts of foods needed for healthy bones. In this regard, dietary recommendations for minerals vary between North America and Europe and these are higher than the values that may be necessary in other parts of the world. The management of many children with chronic illnesses includes the use of medications that may affect their bone mineral metabolism. Routine lab testing for bone mineral metabolism including the serum 25-hydroxyvitamin D level is not indicated, but is valuable for at-risk children, especially those with chronic illnesses.

The Effect of Swimming Training on Bone Mineral Metabolism in Female Swimmers

In this study, the effects of 8-week swimming training applied to swimmers aged 19-25 on bone alkaline phosphatase (bALP), magnesium, calcium, Unsaturated Iron Binding Capacity (UIBC), iron and ferritin parameters were investigated. Mean age of 23.12±5.46 years, 12 swimmers participated in the study. A swimming training program was applied to the participants for 8 weeks/3 days. All tests and measurements were performed before starting the 8-week training program and after the program was completed. The data obtained from the study were analyzed using the SPSS 15.0 package program. The normality distribution of the data was made with the shapiro-wilk test, and the pre-post-test measurements of the participants were analyzed with the Wilcoxon signed-rank test. According to the results of the data, it was determined that there was a statistically significant difference between the metabolic rate, iron, UIBC pre-post test data. (p<0.05). As a result, it can be said that the 8-week swimming training program, which is applied regularly, can positively affect performance with the changes in bone mineral metabolism. Keywords: Ferritin, alkaline phosphatase, calcium, magnesium, metabolic rate

MO473INTERACTION OF SCLEROSTIN AND OSTEOPROTHERIN IN THE DEVELOPMENT OF VASCULAR CALCIFICATIONS AT STAGE 3-5 OF CHRONIC KIDNEY DISEASE

Background and Aims: Background and Aims: . Vascular calcification (VC) due to bone-mineral metabolism disorders is a predictor of high cardiovascular mortality in patients with late-stage chronic kidney disease (CKD) . The established bone-vascular axis in CKD, which relates to interactions between changes in the bone and vascular systems that have similar mechanisms, allows bone metabolism inhibitors to act as potential risk factors for VC. Morphogenetic protein osteoprotegerin (OPG) and glycoprotein sclerostin are opposite inhibitors of bone metabolism: OPG inhibits osteoclastogenesis, sclerostin has an inhibitory effect on osteoblastogenesis. Although both proteins are recognized as high-risk factors for remodeling the heart and large arteries in patients with CKD, the mechanisms and possibilities for correcting these changes are not fully clear. of the study was to investigate the mechanisms of the relationship between OPG and sclerostin in the development of cardiovascular complications due to calcification of the aorta and large arteries in the late stages of CKD. Method: Method The cross-sectional study included 105 patients with stage 3-5 CKD [49 men; 64.0 (23.0-76.0)years]. The glomerular filtration rate determined using the CKD-EPI equation was 38.4 (8.6–92.3) ml / min / 1.73 m2. The general clinical examination included assessment of hematopoiesis (hemoglobin, hematocrit, ferritin and transferrin), determination of total protein and albumin levels, cholesterol, electrolytes (sodium, potassium) in the blood, and indicators of nitrogen metabolism (creatinine, urea). Parameters of bone-mineral metabolism – parathyroid hormone (PTH), calcium, phosphorus, alkaline phosphatase of blood serum-were evaluated. The level of morphogenetic protein OPG and glycoprotein sclerostin was determined using commercial ELISA kit from Biomedica (Austria) by enzyme immunoassay. The morphofunctional features of the aorta and large arteries were studied by duplex scanning using the Doppler effect. We determined the peak systolic velocity of blood flow in the aortic arch (Vps-peak systolic velocity) , which indirectly indicates the state of the aortic wall and its lumen. Echocardiography with Doppler imaging was performed on the "ALOKA 4000" device. The LV myocardial mass index (LVMI), LV hypertrophy variants, LV systolic and diastolic function were determined. Results Cardiovascular damage, which manifests itself in the form of various variants of left ventricular hypertrophy, aortic rigidity, arteriosclerosis and vascular calcification, and directly correlated with the severity of renal failure, was detected in 86% of the examined patients with stage 3-5 CKD. The level of OPG and sclerostin in the blood serum increased with the progression of renal failure from the 3rd to the 5th. The main associations with Vps changes were high OPG levels [OR = 2.39 95% confidence interval (95% CI) (1.34–4.86) for levels ranging from 5.98 to 9.26 pmol / L and OR = 5.54 95% CI (2.64–13.5) for levels ≥9.26 pmol / L; P &lt;0.0001] and high sclerostin levels [OR = 2.64 95% CI (1.42–5.16) for levels ranging from 0.744 to 1.211 ng / ml and OR = 3.69 95% CI (1.76–7.31) for a level ≥1.211 ng / ml; P = 0.0001]. Thus, the logistic regression model showed that the risk of aortic calcification was significantly increased when both OPG (≥5.98 pmol / L) and sclerostin (≥0.744 ng / ml) levels were high [ uncorrected model: OR = 11.93 (4.54–25.2); P &lt;0.0001; on the model adjusted for generally recognized cardiovascular disease risk factors: OR= 5.55 (1.43–1914); P = 0.02]. Conclusion The results suggest that bone metabolism inhibitors, OPG and sclerostin, are independently associated with aortic calcification with potential additive effects in patients with stage 3-5 CKD. The risk of vascular calcification was significantly increased when OPG and sclerostin levels were high

MO199DENOSUMAB: NOVEL APPROACH TO TREATMENT OF OSTEOPOROSIS IN RENAL DISEASE

Background and Aims Denosumab is a fully human monoclonal antibody to the receptor activator of nuclear factor kappa-B ligand (RANKL), an osteoclast differentiating factor. It inhibits osteoclast formation, decrease bone resorption, increase bone mineral density (BMD), and reduce the risk of fracture. There is no restriction of its use in patients with renal disease, for whom biphosphonates are considered controindicated. The aim of our study was to evaluate the effectiveness in reducing facture risk and safety of Denosumab in patients with Osteoporosis and renal disease. Method This is a prospective analysis of 17 patients with Osteoporosis (average T-score below -2.5) admitted to our Nephrology Department for CKD in the last four years. in Vasculitis, Renal Allograft Recipients. Patients with severe Hyperparatiroidism were excluded. We estimated creatinine clearance (eGFR) using Cockcroft-Gault and classified levels of kidney function using the modified National Kidney Foundation classification of CKD. All patients were adequately supplemented with calcium and vitamin D before and while taking Denosumab 60 mg every 6 months. The primary endpoint is the change in bone mineral density (BMD) at one and two years. Secondary endpoints include changes in bone mineral metabolism parameters (Ca, P, PTHi, 25-OH VitD), incidence of fractures, and renal/allograft fuction at one and two years. Results The mean age was 52.5±4 years and 8/17 (47%) were females. N.13 patients (76.5%) were renal transplant recipients (RTR) on standard triple immunosoppression including steroids (prednisone 5 mg/day), CNI and MMF, with average eGFR 65.7±12.5 ml/min. N.2 patients (11.75%) were in hemodialysis. N.2 patients (11.75%) with Anca Vasculitis on steroid therapy and average eGFR 35.6±7.2 ml/min. All patients enrolled were with a BMD T-score of greater than -4.0 and less than -2.5. Only 2 patients had a history of fractures confirmed by a radiology report. Baseline parameters: calcium 9.8±0.32 mg/dl, phosphate 3.9±0.8 mg/dl, PTHi 137±91.0 ng/L, 25-OH VitD 18.3±8.9 ng/mL. From baseline at 1 month there were an increase in PTH and a decrease in calcemia in only 2 transplant recipients (CKD II and IV), that improved with an increased dose of Vit D. There were no significant difference in baseline bone mineral metabolism parameters to year 1 and 2 in all other patients. We found no difference in eGFR and proteinuria from baseline to 1 and 2 years in RTR and ANCA vasculitis. Significant improvement in T-score was observed at 1 year and 2 years (&lt; -1) in all patients. No one discontinued therapy for adverse events. Conclusion Denosumab may have advantages in patients with kidney dysfunction, because not excreted by the kidney and there is no need for dose adjustment. This prospective study showed a significant improvement in osteoporosis (at Dexa mean T-score ≤ -1), but particular attention should be paid to ensuring that patients are calcium and Vitamin D replete.

Influence of long-term controlled therapeutic exercises on blood pressure profile parameters, elastic properties of arterial wall, metabolic and mineral indices in females with arterial hypertension

Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Tyumen Cardiology Research Center, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia Objective To study the role of therapeutic exercises (TE) in the correction of blood pressure, stiffness of the vascular wall, metabolic indices of body structure (volume, mass, area of visceral fat) and bone mineral metabolism in postmenopausal hypertensive patients. Methods. The study included 138 patients (mean age was 58.32 ± 7.61 years). All patients are divided into 3 groups. The first control group is 20 women without arterial hypertension and menopausе. The second group consisted of 58 patients with arterial hypertension (AH) and postmenopause who was not undergone complex of TE and the 3rd group - 60 women with AH and postmenopause who was undergone TE complex. Patients of all groups were examined in dynamics: at the starting point of the study and in 12 months after, ambulatory monitoring of blood pressure; sphygmography; densitometry and test for serum biochemistry parameters of blood samples, including sex hormones, vitamin D. Results. In the course of the study, blood pressure, vascular wall stiffness parameters, metabolic indices of body structure and disorder parameters of bone mineral metabolism were comparable in group 2 and 3 against the background of significantly reduced levels of sex hormones. Multidirectional correlation relationships between the studied parameters are revealed. The basic therapy in combination with therapeutic exercises led to a significant decrease in blood pressure and metabolic indices of body structure (p&lt;.001) and to a persistent tendency of decrease the pulse wave velocity and increase of bone mineral metabolism in gr.3. Conclusion. The result of the study indicates that the exercise therapy complex used in the form of regular classes can be recommended for implementation in clinical practice with the aim of comprehensively affecting the patient’s body and developing personalized treatment tactics for postmenopausal women with hypertension.

Concentrations of Ca, Mg, P, Prostaglandin E2 in Bones and Parathyroid Hormone; 1,25-dihydroxyvitamin D3; 17-β-estradiol; Testosterone and Somatotropin in Plasma of Aging Rats Subjected to Physical Training in Cold Water

Exposure to low temperatures can be considered a stressor, which when applied for a specific time can lead to adaptive reactions. In our study we hypothesized that cold, when applied to the entire body, may be a factor that positively modifies the aging process of bones by improving the mechanisms related to the body’s mineral balance. Taking the above into account, the aim of the study was to determine the concentration of calcium (Ca), magnesium (Mg), and phosphorus (P) in bones, and to examine bone density and concentrations of the key hormones for bone metabolism, namely parathyroid hormone (PTH), somatotropin (GH), 1,25-dihydroxyvitamin D3, 17-β estradiol, testosterone (T) in plasma, and prostaglandin E2 (PGE2) in the bone of aging rats subjected to physical training in cold water. The animals in the experiment were subjected to a series of swimming sessions for nine weeks. Study group animals (male and female respectively) performed swimming training in cold water at 5 ± 2 °C and in water with thermal comfort temperature (36 ± 2 °C). Control animals were kept in a sedentary condition. Immersion in cold water affects bone mineral metabolism in aging rats by changing the concentration of Ca, Mg, and P in the bone, altering bone mineral density and the concentration of key hormones involved in the regulation of bone mineral metabolism. The effect of cold-water immersion may be gender-dependent. In females, it decreases Ca and Mg content in bones while increasing bone density and 17-β estradiol and 1,25-dihydroxyvitamin D3 levels, and with a longer perspective in aging animals may be positive not only for bone health but also other estrogen-dependent tissues. In males, cold water swimming decreased PTH and PGE2 which resulted in a decrease in phosphorus content in bones (with no effect on bone density), an increase in 1,25-dihydroxyvitamin D3, and increase in T and GH, and may have positive consequences especially in bones and muscle tissue for the prevention of elderly sarcopenia.

Role of reduced thyroid hormone status on bone mineral metabolism

Background: The most common endocrine disorder is hypothyroidism which accounts to 11%. Thyroid hormones have a wide array of functions such as physiological growth and development of skeletal system, maintenance of basal metabolic rate and regulation of various metabolisms, including mineral metabolism. Nowadays due to its direct action on bone turn over, thyroid hormones are considered to have an important role on bone mineral metabolism. Thyroid disorders are important cause for secondary osteoporosis. So the present study was done to know the levels of bone minerals, calcium and phosphorus in hypothyroidism and its relation with thyroid hormone levels. Methods: A case-control study was conducted on 30 hypothyroid patients and 30 euthyroid healthy controls in the age group of 20-60 years. Blood samples were collected from all the study population. Serum total triiodothyronine, total thyroxine and TSH by Enzyme-Linked Immunosorbent Assay, Serum calcium by Arsenazo III method, phosphorous by ammonium molybdate method were estimated. Results: Serum calcium levels in cases was found to significantly reduced when compared to controls (p<0.001). Serum phosphorous levels also showed considerable elevation in cases when compared to controls (p<0.001). There was a significant negative correlation between TSH and serum calcium in cases. Conclusion: The present study indicated the important role of reduced thyroid hormone status on bone mineral metabolism. This study concludes that serum calcium was significantly reduced and phosphorus levels were significantly increased in hypothyroid patients when compared to euthyroid control subjects. So frequent monitoring of serum calcium and phosphorus in hypothyroid patients would reduce the burden of bone pathologies.