scholarly journals The action of vitamin D on the degree of mineralization of bone tissue in rats given adequate amounts of calcium and phosphorus in the diet

1970 ◽  
Vol 24 (1) ◽  
pp. 29-38 ◽  
Author(s):  
P. Rasmussen

1. The action of vitamin D on the degree of mineralization of the bone tissue of rats given a diet containing adequate amounts of calcium and phosphorus for 8 weeks has been investigated by quantitative microradiography. The method is described.2. There was a significant reduction in the growth of the vitamin D-deficient rats; the reduction was most marked in the females.3. Serum analysis showed a reduction in Ca, but P was unchanged. However, the Ca × P product was considered to be high enough to permit normal mineralization.4. The degree of mineralization of the cortical bone tissue increased significantly according to the distance from the epiphyseal plate. However, there were no significant differences between vitamin D-treated and vitamin D-deficient animals.5. It is concluded that vitamin D deficiency in rats does not prevent the formation of a bone matrix which can attain a normal degree of mineralization.

2021 ◽  
pp. 45-52
Author(s):  
N.S. Shevchenko ◽  
◽  
L.F. Bogmat ◽  
Yu.V. Khadzhinova ◽  
◽  
...  

Osteopenia (osteopenic syndrome) and osteoporosis (OP) are among the frequent and highly disabling conditions that accompany the development of rheumatic diseases (RD), including juvenile idiopathic arthritis (JIA). Changes in the requirements for the diagnosis and treatment of children with JIA according to the treatment strategy to achieve the goal (treat to target) have led to a decrease in the frequency of development and manifestations of OP in patients with RD. The condition of bone tissue in children with JIA, against the background of modern therapy and in conditions of widespread vitamin D deficiency requires further study. Purpose — to study bone mineral density (BMD) in children with JIA in modern disease management and to identify adverse factors for the development of OP among clinical signs. Materials and methods. We examined 35 children with JIA aged 7 to 17 years, mostly female (77.1%), with oligo (25.7)%, poly (60.0%) and undifferentiated (14.3%) option, 53.4% of whom have not yet received basic therapy. All patients underwent BMD by dual-energy X-ray absorptiometry on a bone densitometer Explorer QD W (Hologic), parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D], total and ionized calcium and phosphorus in syvo. The control group consisted of 12 healthy children of the same age with a normal level of 25(OH)D. Results. The mean level of vitamin D in the serum of children in the main group was 20.41±1.35 ng/ml, which was significantly lower than in the control group (30.03±2.53 ng/ml, p<0.05); the frequency of low levels of vitamin D reached 88.57%. The content of calcium and phosphorus in the blood did not deviate from the normative values, despite the widespread deficiency of vitamin D. 98.37% of patients had normal PTH values, the average level in the blood was 30.43±0.90 pg/ml. The content of PTH was the highest in non-differential arthritis (34.33±1.80 pg/ml), the lowest in the oligoarticular variant (28.36±1.43 pg/ml, p<0.05). PTH concentrations correlated with vitamin D levels (r=-0.41; p<0.05) and were independent of patient gender and disease activity. The frequency of decreased BMD was 28.57% of the surveyed children. The prevalence of osteopenia was the same in different variants of arthritis and did not depend on the sex and age of patients, positivity in the RF. Osteopenic syndrome was significantly more common in ANA-positive JIA than in ANA-negative variant (46.15% vs. 18.18%; pϕ<0.05). The condition of bone tissue (Z-criteria) depended on BMI (r=0.33; p<0.05), disease activity on the JADAS scale (r=0.35; p<0.04), the number of active joints (r=0.34; p<0.05); ANA level (r=-0.34; p<0.05). In the group of children with osteopenic syndrome, BMD correlated with the duration of the disease (r=-0.67; p<0.05), the number of active joints (r=-0.62; p<0.05), the level of blood phosphorus 0.74; p<0.05) and the sum of points on the JADAS scale (r=0.59; p<0.05). In the group of children with preserved BMD, the spectrum of correlations was supplemented by indicators of vitamin D status (r=-0.33; p<0.05) and BMI (r=-0.40; p<0.05). Conclusions. In children with JIA, the incidence of osteopenia is 28.57% with vitamin D deficiency in 88.57% of patients, preserved levels of total calcium, phosphorus and PTH in the blood. Decreased BMD in the early stages of JIA is associated with a younger age of patients and the age of onset of the disease, increased prevalence of joint syndrome, inflammatory and serological activity of the disease, ionized calcium and blood phosphorus, PTH levels and decreased vitamin D (р<0,001). The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of these Institutes. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: bone mineral density; juvenile idiopathic arthritis; osteopenia; 25-OH-vitamin D; parathyroid hormone.


JMS SKIMS ◽  
2011 ◽  
Vol 14 (2) ◽  
pp. 40-42
Author(s):  
Muzafar Maqsood Wani ◽  
Imtiaz Ahmed Wani

Major biologic function of activated vitamin D is to maintain normal blood levels of calcium and phosphorus, thus regulating bone mineralization. Research suggests that vitamin D may help in immunomodulation, regulating cell growth and 1,4 differentiation as well as some diverse unspecified functions. Overt vitamin D deficiency leads to hypocalcaemia, secondary hyperparathyroidism and increased bone turnover, which in prolonged and severe cases may cause rickets in children and osteomalacia in elderly.... JMS 2011;14(2):40-42


2020 ◽  
Vol 22 (2) ◽  
pp. 23-31
Author(s):  
Olga O. Golounina ◽  
Gyuzel E. Runova ◽  
Valentin V. Fadeyev

Osteoporosis is the most common cause of low bone mineral density (BMD) and low-traumatic fractures in adults. However, differential diagnosis should also consider other causes of decreased BMD, including osteomalacia, as treatment for these conditions vary significantly. Osteomalacia is a systemic disorder characterized by decrease in bone strength due to of excessive accumulation of non-mineralized osteoid and uncoupling between bone matrix formation and mineralization. Osteomalacia in adults mostly develops due to severe vitamin D deficiency of any etiology, less often along with kidney pathology, mesenchymal tumors secreting fibroblast growth factor 23 or hereditary metabolic bone diseases. Clinical symptoms of osteomalacia are nonspecific and mostly manifest by generalized diffuse bone pain, muscle weakness, skeletal deformities and often go unnoticed at initial stage of the disease. Histomorphometric examination is the most accurate method of the diagnosis, which allows assessment of bone formation rate and calcification. The utmost priority of the treatment of osteomalacia of any etiology is the elimination of vitamin D deficiency, hypocalcemia, hypophosphatemia and prevention of bone deformities progression and muscle hypotension.


2020 ◽  
pp. 10-15
Author(s):  
I.V. Vozna ◽  
A.V. Samoilenko ◽  
S.V. Pavlov

The study aims to determine the concentration of vitamin D in the oral fluid, markers of bone destruction as well as to assess the diagnostic value of these indicators to optimize special programs for diagnostics and prevention of major dental diseases in the industrial region’s residents. The object and research methods. There were examined 178 patients. The study group consisted of 126 patients with generalized periodontitis of initial (8), I (32), II (68), and III (18) severity levels, chronic course who are working in hazardous conditions of the "Dniprospetsstal" plant in Zaporizhzhya. The comparison group included 32 patients with periodontitis of initial (5), I (10), II (11), and III (6) severity degrees, which do not have occupational health risks. The control group consisted of 20 relatively healthy individuals without signs of periodontal tissue disease. The level of vitamin D, VDBP, MMP-8, and osteocalcin was determined by enzyme-linked immunosorbent assay. Research results. It is established, that the patients with the initial severity of periodontal disease have minor vitamin D deficiency and as the severity progresses, the vitamin D deficiency increases. Therefore, in the third severity of the inflammatory process, there is a severe deficiency of vitamin D. It should be noted that in the study group patients who were working in hazardous production conditions, the decrease of vitamin D content in the oral fluid was more pronounced relative to the patients in the comparison group with periodontal disease and no occupational hazards. Vitamin D deficiency depends on the severity of periodontitis, which is confirmed by the established strong feedback of the comparison group (γ = -0.790, p <0.05), and that of the study group (γ = -0.778, p <0.05). Periodontitis was accompanied by a significant loss of vitamin D and was associated with a sharp decrease of VDBP protein. That is, not only the concentration of vitamin D changes but so does the protein responsible for the transfer and utilization of this vitamin. We have found a correlation between the VDBP presence in the sample and the severity of periodontitis. Strong feedback of the comparison group (γ = -0.962, p <0.05) and that of the study group (γ = -0.966, p <0.05) was detected. The patients had impaired bone tissue metabolism, which was accompanied by the bone destruction marker MMP-8 increase. The obtained data show a significant increase of MMP-8 content in the oral fluid in periodontitis patients, compared to the individuals with clinically intact periodontium, and reliably reflects the severity of the disease. We have established a direct strong connection between the level of MMP-8 in the oral fluid and the degree of the disease using the method of mathematical analysis. The correlation coefficient was (γ = 0.892, p <0.05) in the comparison group and (γ = 0.965, p <0.05) in the study group. The results of studying bone tissue formation activity considering the level of osteocalcin have shown that osteocalcin decreases with increasing severity of the disease. The correlation between osteocalcin levels and disease severity in the patient groups had strong feedback both in the comparison group (γ = -0.919, p <0.05) and in the study group (γ = -0.987, p <0.05). Conclusions. Biochemical markers allow detecting disorders of bone tissue metabolism and their level of concentration depends on the severity of periodontal tissue disease. The vitamin D deficiency, the concentration of VDBP, MMP-8, osteocalcin are more pronounced in the patients with periodontal disease experiencing occupational hazards compared to the patients who are not exposed to such conditions. The obtained results substantiate the feasibility of enzyme-linked immunosorbent assay introducing vitamin D, VDBP, MMP-8, osteocalcin in laboratory screening of periodontal tissue diseases as highly informative biochemical markers used for diagnostics and prognosis.


2019 ◽  
Vol 181 (5) ◽  
pp. 509-517 ◽  
Author(s):  
F P Paranhos-Neto ◽  
L Vieira Neto ◽  
M Madeira ◽  
A B Moraes ◽  
L M C Mendonça ◽  
...  

Introduction The role of vitamin D on bone microarchitecture and fragility is not clear. Objective To investigate whether vitamin D deficiency (25(OH)D <20 ng/mL) increases cortical bone loss and the severity of fractures. Design Cross-sectional study of 287 elderly women with at least one prevalent low-impact fracture. Methods Biochemistry, X-rays to identify vertebral fractures (VFs) and to confirm non-vertebral fractures (NonVFs), and high-resolution peripheral quantitative computed tomography (HR-pQCT) to evaluate bone microstructure. Results Serum 25(OH)D levels were associated with body mass index (BMI: r = −0.161, P = 0.006), PTH (r = −0.165; P = 0.005), CTX (r = −0.119; P = 0.043) and vBMD at cortical bone (Dcomp: r = 0.132; P = 0.033) and entire bone (D100: r = 0.162 P = 0.009) at the distal radius, but not at the tibia. Age and PTH levels were potential confounding variables, but in the multiple linear regressions only BMI (95% CI: 0.11–4.16; P < 0.01), 25(OH)D (95% CI: −0.007 to 1.70; P = 0.05) and CTX (95% CI: −149.04 to 21.80; P < 0.01) predicted Dcomp, while BMI (95% CI: 1.13–4.18; P < 0.01) and 25(OH)D (95% CI: 0.24–1.52; P < 0.01) predicted D100. NonVFs predominated in patients with 25(OH)D <20 ng/mL (P = 0.013). Logistic regression analysis showed a decrease in the likelihood of presenting grade 2–3 VFs/NonVFs for every increase in 25(OH)D (OR = 0.962, 95% CI: 0.940–0.984; P = 0.001), BMI (OR = 0.932, 95% CI: 0.885–0.981; P = 0.007) and D100 at radius (OR = 0.994, 95% CI: 0.990–0.998; P = 0.005). Conclusion In elderly patients with prevalent fractures, vitamin D deficiency was associated with cortical bone loss and severity of fractures.


1968 ◽  
Vol 22 (1) ◽  
pp. 77-82 ◽  
Author(s):  
P. A. Thornton

1. The skeletal response of vitamin D-deficient chicks to dietary ascorbic acid was tested.2. The epiphyseal cartilaginous plate width, which was increased by the vitamin D deficiency, was further increased when ascorbic acid was added and the effect appeared sooner.3. Absence of vitamin D was associated with a reduction in the relative amount of cancellous to compact bone ash in the tibia. Dietary ascorbic acid intensified this effect to a significant degree.4. Plasma ascorbic acid levels in rachitic chicks were approximately 25% less than in controls. This observation may explain the skeletal response to added vitamin C and suggests that avian bone tissue has a particularly high requirement for this vitamin.


2014 ◽  
Author(s):  
Vladyslav Povoroznyuk ◽  
Olena Tyazhka ◽  
Nataliya Balatska ◽  
Tetyana Budnik ◽  
Inga Kubey ◽  
...  

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