The link between vitamin D, chemerin and metabolic profile in overweight and obese children - preliminary results.

Background: Vitamin D affects adipogenesis, oxidative stress, inflammation, secretion of adipocytokines, lipid metabolism and thermogenesis. Some researchers postulate that those effects could be exerted by the influence of vitamin D on chemerin levels. Aim of the study: We aimed to investigate if there is a link between serum 25-hydroksyvitamin D [25(OH)D], chemerin and metabolic profile in overweight and obese children before and after vitamin D supplementation. Material and methods: The prospective study included 65 overweight and obese children aged 9.08-17.5 years and 26 peers as a control. None of the patients in the study group had received vitamin D within the last twelve months before the study. Results: The study group had lower baseline 25(OH)D (p<0.001) and higher chemerin (p<0.001), triglycerides (TG, p<0.001), triglycerides/high density lipoprotein cholesterol (TG/HDL-C, p<0.001), C-reactive protein (CRP, p<0.05), fasting insulin (p<0.001), Homeostasis Model Assessment - Insulin Resistance (HOMA-IR, p<0.001), alanine aminotransferase (ALT, p<0.001) and uric acid (p<0.001) compared to the control group. Baseline vitamin D was related to fasting insulin (R=-0.29, p=0.021), HOMA-IR (R=-0.30, p=0.016), HDL-C (R=0.29, p=0.020) and uric acid (R=-0.28, p=0.037) in the study group. Baseline chemerin was related to insulin at 30' (R=0.27, p=0.030), 60' (R=0.27, p=0.033), 90' (R=0.26, p=0.037) and 120' (R=0.26, p=0.040) during the oral glucose tolerance test (OGTT) and ALT (R=0.25, p=0.041) in the study group. Correlation between vitamin D and chemerin (R=-0.39, p=0.046) was found only in the control group. After six months of vitamin D supplementation a decrease in CRP (p<0.01), total cholesterol (p<0.05), ALT (p<0.01), glucose at 150' OGTT (p<0.05) was observed. Moreover, we noticed a tendency for negative association between 25(OH)D and chemerin levels (p=0.085). Multivariable backward linear regression models were build using baseline vitamin D, baseline chemerin and six months chemerin as the dependent variables. Conclusions: Our study confirmed that vitamin D has positive effect on metabolic profile in overweight and obese children. The relationship between vitamin D and chemerin is not clear, nevertheless we have observed a tendency to decrease chemerin concentrations after improving vitamin D status, even without a significant reduction in body fat mass.

Decreased level of soluble receptor activator of nuclear factor-κß ligand (sRANKL) in overweight and obese children.

Introduction: Childhood obesity contributes to the development of cardiovascular diseases. The molecular pathway - receptor activator of nuclear factor-κß ligand (RANKL), its receptor RANK and osteoprotegerin (OPG) - takes part not only in bone metabolism but is also involved in the atherosclerosis process. RANKL stimulates osteogenic differentiation and calcification of vascular smooth cells. The associations between the OPG-sRANKL system and various cardiovascular risk factors were displayed. We aimed to evaluate the relationships between serum sRANKL (soluble RANKL) levels and the OPG/sRANKL ratio with cardiometabolic risk factors in overweight and obese children. Material and methods: The study included 70 children with overweight and obesity (mean age 13.0 ± 2.8) and 35 age-matched normal weight, healthy peers as a control group. In all patients, anthropometric measurements and laboratory tests were performed. Additionally, an oral glucose tolerance test (OGTT) was made only in overweight and obese children. Atherogenic and insulin resistance indices were calculated. Results: Overweight and obese children had lower sRANKL levels compared to the control group (median 276.95 vs 325.90, p=0.011), and consequently a higher OPG/sRANKL ratio (0.02 vs 0.01, p = 0.013). The studied children in the lowest quartile of sRANKL levels had higher body weight, Body Mass Index, waist circumference and increased glucose and insulin levels 60 minutes after OGTT and higher uric acid values compared to children in the highest quartile. In multivariable linear regression analysis sRANKL negatively correlated only with uric acid (ß = - 0.508, p = 0.041). No association was found for the OPG/sRANKL ratio. Conclusion: Excess fat mass seems to alter the OPG/RANKL ratio mainly by reducing serum sRANKL levels. The correlation between sRANKL and uric acid may suggest a contribution of the OPG-sRANKL system in the cardiometabolic process, but that observation should be confirmed in future studies.

Changes of Peripheral Th17 Cells Subset in Overweight and Obese Children After Body Weight Reduction.

Background: Obesity has been a growing problem in young patients leading to serious metabolic complications. There are many studies supporting the idea, that obesity should be considered as a chronic inflammation closely associated with immune system alterations. Th17 subpopulation is strongly involved in this process. The aim of our study was to evaluate circulating Th17 cells in overweight and obese children and explore the relationships between Th17 subset and metabolic parameters. Methods: We evaluated peripheral Th17 cells in fresh peripheral blood samples from 27 overweight and obese and 15 normal-weight children. Th17 cells were identified by flow cytometry using monoclonal antibody and intracellular IL-17A staining. Th17 cells were defined as CD3+CD4+CD196+IL-17Aic+. The analysis involved anthropometric and metabolic parameters measured at baseline and three months after the change of lifestyle and diet. We evaluated the relationship between metabolic parameters and Th17 cells. Results: In overweight and obese children we found significantly higher Th17 cells percentage compared to normal weight controls (median 0.097% (0.044 - 0.289) vs 0.041% (0.023 - 0.099), p = 0.048). The percentage of Th17 cells decreased statistically significantly in children who reduced weight after the intervention (0.210% (0.143 - 0.315) vs 0.039% (0.028 - 0.106), p = 0.004). In this group we also noticed statistically significant reduction of TC and LDL-C concentration (p = 0.01, p = 0.04, respectively). Conclusions: Obesity in children is associated with increased percentage of peripheral Th17 cells. Weight reduction leads to significant decrease of circulating Th17 cells and improvement of lipid parameters. This significant reduction of proinflammatory Th17 cells is a promising finding suggesting that obesity-induced inflammation in children could be relatively easily reversible.

Obesity and chronic inflammation crosslinking.

The adipose tissue has been recognized as an active organ involved in numerous metabolic, hormonal and immunological processes. Obesity and associated chronic inflammation leads to many metabolic and autoimmune disorders. The number of cells, their phenotype and distribution in adipose tissue depends on the degree of obesity. Polarization of macrophages towards M1, neutrophils influx to adipose tissue, activation of Th1 and Th17 cells and increased level of proinflammatory cytokines are characteristic for obesity-induced inflammation. Several mechanisms, such as adipocytes' hypoxia, oxidative stress, endoplasmic reticulum stress, impairment of PPAR receptors, inflammasomes' activation and activation of TLR are involved into development of chronic obesity-induced inflammation. A better understanding of this processes can provide new treatments for obesity and related disorders.

Graves' disease in children in the two decades following implementation of an iodine prophylaxis programme.

Grave's disease (GD) is a form of thyroid autoimmune disease characterised by hyperthyroidism. It is a rare clinical problem in paediatrics. Development of disease is the result of genetic susceptibility and some environmental factors. One of the best-documented environmental factors involved in thyroid autoimmunity is iodine excess. The aim of our study was to analyse the clinical course and response to pharmacological treatment in children diagnosed with Graves' disease in first two decades after mandatory salt iodination. Records of 94 children diagnosed with GD in the years 1998-2017 were analysed. Medical data of patients was compared between two decades following implementation of iodine prophylaxis: 1998-2007 (first-decade group - FDG) and 2008-2017 (second-decade group - SDG); 34 and 60 patients, respectively. Medical data of FDG was obtained from archival records and previous analysis performed in 2006. Data of 60 patients from SDG were obtained from currently available medical records. Results were statistically analysed using Microsoft Excel and Statistica 11 software. Results: In our study, after mandatory salt iodination, the tendency of an increase in newly diagnosed GD in children without family susceptibility was observed. The antibody profile indicates the significant contribution of the autoimmune process involving all thyroid antigens; therefore, the term "autoimmune hyperthyroidism" seems to be more appropriate than classical GD in this group of patients. The first-choice treatment with methimazole rarely causes adverse events during the therapy, and they have benign character.

Regulatory T Cells in Obesity.

The current concept of the pathogenesis of obesity relates to the inflammation caused by excess of adipose tissue. Regulatory T cells accumulated in visceral adipose tissue (VAT-resident Tregs) are also involved in this pathogenesis. In the present paper the mechanisms responsible for alterations in the number and function of VAT-resident Tregs T in obesity are described. The role of Tregs in inflammation, insulin resistance, atherogenesis, and also the influence on VAT-resident Tregs of adipocytokines and insulin are reviewed.

Anti-natrium/iodide symporter antibodies and other anti-thyroid antibodies in children with Turner's syndrome.

Antibodies against the Na/I symporter (anti-NIS ab) have been found in adult patients with autoimmune thyroid diseases. As easily available for the immune system, NIS can play a role in the initial stage of autoimmune thyroid diseases. Children with Turner's syndrome (TS) being at high risk of autoimmune thyroid disease development seem a valuable group for the investigation of the early autoimmune process. The aim of the study was to investigate the presence of anti-NIS ab and its potential clinical significance in TS children. Fifty four girls with TS were examined (age 11.9 ± 2.46 years), and 23 healthy girls with normal thyroid function, free of autoimmune diseases. Anti-NIS antibodies were measured by the in-house ELISA method and the Western blotting. Sera considered positive for anti-NIS ab were used for the iodide uptake bioassay using COS7 cells stably transfected with hNIS. In all patients the thyroid function, antithyroid antibodies presence and thyroid ultrasonography were evaluated. In 20% of the patients a subclinical hypothyroidism was diagnosed and 70.4% had antithyroid antibodies (anti-TPO - 64.8% and Anti-Tg - 24%). Anti-NISab were present in 14.8% girls with TS and in none of the control group. Their presence was unrelated to other antithyroid antibodies titre or patients' age. A positive correlation between the anti-NIS ab presence and the hypothyroidism was found (p < 0.04). Anti-NIS ab-positive sera did not suppress iodine uptake. In conclusion, anti-NIS antibodies were present in 14.8% of children with TS and they were related to the presence of hypothyroidism.

Expression of cytotoxic T lymphocyte antigen-4 in T cells from children with Hashimoto's thyroiditis.

The cytotoxic T lymphocyte antigen-4 (CTLA-4) (CD152) is a basic negative regulatory molecule of T cell activation and its hypo-function is associated with severe lymphoproliferative syndrome. The aim of the present study was to evaluate the intracellular and surface expression of CTLA-4 on peripheral T cells before and after T cell activation in children with Hashimoto's thyroiditis (HT). Blood samples were obtained from 46 children: 25 with Hashimoto's thyroiditis and 21 controls free of autoimmune disease or thyroid disorders. T cell phenotype was evaluated by flow cytometry with the use of monoclonal antibodies combination: CD4- FITC/ CD28 -PC5/ CD152 -PE and CD8 -FITC/ CD28 -PC5/ CD152 -PE on T cell surface and intracellularly at baseline and after 48 h of T cell culture with the mitogen 48-PHA. We found that the number of T cells with intracellular CD152 expression was comparable in HT patients and controls at baseline and increased after 48-PHA, in CD4 subset only, in both patients and controls. However, the increase was more evident in the HT patients. The number of T cells with the surface expression of CD152 at baseline was significantly lower in the HT patients than in controls (p < 0.0002) in non-stimulated CD4+ and CD8+ T cells. After 48-PHA, surface CD152 expression in CD4+T cells increased in both groups; the increase was greater in controls. In conclusion, impaired function of CTLA-4 in HT patients may depend on the imbalance of intracellular/surface expression of CD152 in T cells.

Association between the polymorphism A/G at position 49 of exon 1 of the CTLA-4 gene and antithyroid antibody production in children with Hashimoto's thyroiditis.

UNLABELLED: CTLA-4 gene is considered to be one of the strongest factors determining the predisposition to antithyroid antibody (Ab) production. The aim of the study was to evaluate the association of the polymorphism A/G of exon 1 of CTLA-4 gene and antithyroid Ab level in children with Hashimoto's thyroiditis (HT). MATERIAL AND METHODS: 45 children with HT (aged 14.9 ± 2, range 8.1-7.9) and 55 healthy controls (aged 14.8 ± 2.34, range 8.0-17.4) were enrolled. Controls were euthyroid and free from any autoimmune disease. CTLA-4 gene (+49)A/G polymorphism was evaluated by a single-strand conformation polymorphism method and restriction fragment-length polymorphism. RESULTS: The frequency of GG genotype in HT children was significantly higher than in controls: 31 vs. 14.5% respectively (p < 0.04, OR = 2.65, CI = 0.99-7.06). Anti-Tg Ab titers were higher in patients homozygous for G allele than with AA genotype. The GG genotype seemed to be protective from hypothyroidism at the moment of HT diagnosis, but this observation was not statistically confirmed. CONCLUSIONS: Our study provides the evidence supporting the association between CTLA-4 gene (+49)A/G polymorphism and the susceptibility to HT in Polish children and confirms the existence of a link between (+49)A/G polymorphism and anti-Tg Ab level.

Decreased CD4+CD152+ T cell subset and its correlation with the level of antithyroid antibodies in children with chronic autoimmune thyroiditis.

OBJECTIVE: Cytotoxic T lymphocyte antigen-4 (CTLA-4) is one of the basic antigens involved in immune responses regulation associated with autoimmune thyroid diseases. The aim of the study was to evaluate whether the surface expression of CTLA-4(CD152) on T cells is correlated with laboratory autoimmune markers in children with Hashimoto's disease. MATERIAL AND METHODS: Blood samples were obtained from 45 children with Hashimoto's thyroiditis of the mean age 14.8 ±2.35 years, and from 55 healthy age-matched children, free of allergic, immune and hematological disorders, and with a normal thyroid function. The anti-thyroid antibodies were measured with Microparticle Enzyme Immunoassay (AxSYM Anti-Tg, AxSYM Anti-TPO). The T cell phenotype was evaluated flow cytometery, with the use of monoclonal antibodies combination: CD4- FITC/ CD28 -PC5/ CD152 -PE and CD8 -FITC/ CD28 -PC5/ CD152 -PE. - RESULTS: The percentage of T cells with CD152 expression was significantly decreased in children with Hashimoto's thyroiditis compared with healthy controls (P<0.001). A significant negative correlation was found between the level of anti-thyroglobulin antibodies and the percentage of CD4+CD152+ T cells (r = -0.34; P<0.05). Anti-thyroperoxidase antibodies did not correlate with CD152 expression. CONCLUSIONS: In children with Hashimoto's thyroiditis, the number of CD4+CD152+ T cells is decreased and negatively correlates with the level of anti-thyroglobulin antibodies.

[The alterations of body composition in children with growth hormone deficiency during first two years of growth hormone treatment]. / Zmiany skladu ciala u dzieci z somatotropinowa niedoczynnoscia przysadki w pierwszych dwóch latach leczenia hormonem wzrostu.

INTRODUCTION: In children the most significant effect of growth hormone (GH) treatment is an increase of growth velocity, but improved body composition seems to be also an important element of normal metabolic status in childhood. AIM OF STUDY: To evaluate the alterations of body composition and their association with growth promoting effect during 2 years of GH treatment in children. MATERIAL AND METHODS: 50 pre-pubertal children with GH deficiency were evaluated: 11 girls and 39 boys. Mean age at the start of therapy was: 10.1+/-2.83 years. Dose of GH was 0.17 mg/kg/week. Body composition was evaluated by body mass index (BMI), skinfold thicknesses, body circumferences (waist, hip). Lean body mass (LBM) and fat mass (FM) were calculated by Slaughter's equation. Measurements were performed at the start, after 3, 6 and next each 6 months during 2 years of GH treatment. RESULTS: In the majority of patients LBM increased during the therapy and reached the highest values after 6 months (85.55%, p < 0.05). In next measurements LBM slightly decreased, but did not differ significantly in comparison with 6 month of therapy. Complementary tendencies were observed in FM: it decreased significantly after 6 months (DeltaFM = 4.49%) and maintained after 12 and 24 months without any significant changes. No differences were found in BMI. WHR changed significantly after 24 months. No correlation was found between the grade of changes of LBM, FM and the strength of the growth promoting effect. CONCLUSIONS: 1. The alterations of the body composition in GH deficient children treated with GH are occur during the first 6 moths of therapy, and next maintains a new balance of LBM and FM. 2. The anthropometric evaluation of body composition based on skinfolds measurement is the useful method for the assessment of LBM and FM changes during GH therapy in children.

[Anthropometric parameters prognosticating a good final height in patients with Turner syndrome during growth hormone therapy]. / Antropometryczne parametry zapowiadajace dobry wzrost ostateczny u dziewczat z zespolem Turnera, leczonych hormonem wzrostu.

INTRODUCTION: Growth hormone treatment in Turner girls is a widely accepted method of their final height improvement. However some patients do not reach satisfactory final height. The aim of the study was to evaluate the anthropometric parameters which would be prognostic for final height in children with Turner syndrome treated with growth hormone. MATERIAL AND METHODS: Data of 18 girls with Turner syndrome who completed growth hormone therapy and reached a final height were analysed. Mean age was 11.32+/-3.04 years. Correlations of final height with following parameters were analysed: trunk to limbs ratio, lower limbs length (in SDS), growth velocity in the first years of GH therapy. From among other characteristics which could determine the final height the karyotype, age at the start of GH therapy were evaluated. RESULTS: The mean height gain in the group was 8.4 cm (range: 0.6-19.9 cm). Final height over 3rd percentile for the healthy population achieved 33.3% patients. Growth velocity in first 2 years of therapy correlated negatively with final height. Patients with final height over 3rd percentile had statistically significant greater mean height gain. Patients with low final height had a significantly greater deficit of leg length and increased Trunk/Leg Length index. Age at the beginning and duration of therapy had no influence on final height. CONCLUSIONS: Better final height reach the patients who have more advantageous Trunk/Leg Length index before and during therapy, and reduction of leg length deficiency is relatively greater than height deficiency reduction.

[Thyroid volume evaluation in girls with Turner syndrome according to normal range for healthy population]. / Ocena objetosci tarczycy u dziewczat z zespolem Turnera wedlug norm dla zdrowej populacji.

INTRODUCTION: Turner syndrome is a common chromosomal aberration. Among other features of that syndrome susceptibility to autoimmune diseases is well known. Most often there is Hashimoto's thyroiditis. Because of short stature the evaluation of thyroid volume according to chronological age seems to be not efficient. THE AIM of the study was to find an adequate method of thyroid volume evaluation in girls with Turner syndrome using standards for healthy children. MATERIAL AND METHODS: 54 girls with Turner syndrome were examined, mean age was 11 years and 9 months. Physical and ultrasonographic examination of thyroid gland was performed. The hormonal state and presence of antithyroid autoantibodies were evaluated. The thyroid volume was evaluated according to normal range (by Delange) for chronological and height age of each girl. RESULTS: According to chronological age the thyroid volume was in normal range, but according to height age in 3 patients the thyroid volume was over 97 percentile. They were the same girls in whom we detected goiter according to physical examination. CONCLUSIONS: We suggest that proposed method gives the possibility of an accurate evaluation of thyroid volume in patients with Turner syndrome and in other patients with growth deficiency.