Barbara Głowińska-Olszewska

Relationship between endothelial dysfunction, carotid artery intima media thickness and circulating markers of vascular inflammation in obese hypertensive children and adolescents.

BACKGROUND Adhesion molecules released by dysfunctional endothelium are considered as markers of vascular inflammation in early atherosclerosis. Non-invasive ultrasound methods are now available to detect first preclinical signs of the disease. AIM To investigate the relationship between selected adhesion molecules and ultrasound indicators of early atherosclerosis: endothelial function measured by flow-mediated dilatation (FMD) and intima media thickness (IMT). PATIENTS The study group consisted of 85 children, mean age 14.6 years, of whom 22 were obese, 31 were hypertensive, and 32 obese and hypertensive. The control group included 26 healthy children. METHODS Adhesin concentrations were determined by ELISA. FMD and IMT were evaluated by ultrasound. RESULTS A positive correlation was found between sICAM-1 (soluble intercellular adhesion molecule 1) and IMT (r = 0.32, p = 0.013, 95% CI: 0.11 to 0.49) and a negative correlation between IMT and FMD (r = -0.26, p = 0.04, 95% CI: -0.43 to -0.04) in the whole study group. In the particular groups, we found significant correlations only in obese hypertensive children. sICAM-1 correlated positively with IMT (r = 0.52, p = 0.001, 95% CI: 0.2 to 0.72) and negatively with FMD (r = -0.31, p = 0.027, 95% CI: -0.6 to -0.2). sE-selectin correlated positively with IMT (r = 0.41, p = 0.012). In regression models, IMT correlated with sICAM-1 (beta = 0.37, p = 0.03) and body mass index (beta = 0.55, p = 0.02), and FMD correlated negatively with sICAM-1 (beta = -0.47, p = 0.04). CONCLUSIONS The association between inflammatory markers of the endothelium with impaired vasodilatation activity and the first atherosclerotic structural changes in the common carotid arteries were found in obese hypertensive children and adolescents. The coexistence of obesity and hypertension predisposes these young patients to closely related disturbances connected with early atherosclerosis.

Relationship between circulating endothelial progenitor cells and endothelial dysfunction in children with type 1 diabetes: a novel paradigm of early atherosclerosis in high-risk young patients.

OBJECTIVE The low number of circulating endothelial progenitor cells (EPCs) has emerged as a biomarker of cardiovascular (CV) risk in adults. Data regarding EPCs in paediatric populations with CV risk factors are limited. The aim of the study was to estimate the EPC number and its relationship with vascular function and structure in children with type 1 diabetes mellitus (T1DM). DESIGN AND METHODS We performed a comparative analysis of 52 children with T1DM (mean age 14.5 years; diabetes duration, 6.0 years; HbA1c level, 8.5%) and 36 healthy age- and gender-matched control children. EPCs were identified and analysed by flow cytometry with the use of MABs directed against CD34, CD144 (VE-cadherin) and CD309 (VEGFR-2). sICAM-1, hsCRP, thrombomodulin and adiponectin levels were also assessed. We evaluated vascular function (flow-mediated dilation (FMD)) and structure (carotid intima-media thickness (IMT)) ultrasonographically. RESULTS Frequencies of CD34+ cells were similar in both groups (P=0.30). In contrast, frequencies of CD34+VE-cadherin+ cells were significantly higher in diabetic children compared with the healthy group (P=0.003). Similarly, diabetic patients tended to present with higher frequencies of CD34+VEGFR+ cells (P=0.06). FMD was lower (6.9 vs 10.5%, P=0.002) and IMT was higher (0.50 vs 0.44 mm, P=0.0006) in diabetic children. We demonstrated a significant relationship between CD34+VEGFR-2+ cells and BMI (r=0.3, P=0.014), HDL (r=-0.27, P=0.04), sICAM-1 (r=0.47, P=0.023) and FMD (r=-0.45, P<0.001). Similarly, frequencies of CD34+VE-cadherin+ cells were significantly correlated with BMI (r=0.32, P=0.02) and FMD (r=-0.31, P=0.03). CONCLUSIONS We demonstrated here that increased frequencies of EPCs observed in diabetic children are negatively correlated with endothelial function. Further studies are warranted to assess whether this phenomenon might result from effective mobilisation of EPCs in order to repair damaged endothelium in children at increased risk for atherosclerosis.

The association of early atherosclerosis and retinopathy in adolescents with type 1 diabetes: preliminary report

Recent studies have shown a close correlation between advanced diabetic retinopathy and the late stages of atherosclerosis. The purpose of this study was to analyse the association between diabetic retinopathy and early atherosclerotic changes in adolescents with type 1 diabetes. We studied 28 adolescents with type 1 diabetes. Eight patients with nonproliferative retinopathy were compared with the remaining 20 patients, and with 11 healthy controls. The function of endothelium was assessed by measuring flow-mediated dilatation (FMD), the intima-media thickness (IMT) of the common carotid arteries and adhesion molecules (sICAM-1, sVCAM-1, sE-selectin). In the group with retinopathy FMD equalled 7.8±4.1% vs. 12.1±5.1% in the control group (p=0.04), and in the group without retinopathy, 7.6±5.5% (p=0.04 compared to controls). Higher IMT was found in all patients with diabetes in comparison with healthy controls: 0.49±0.06 mm vs. 0.42±0.03 mm (p=0.001). Patients with retinopathy had a significantly higher value of IMT in comparison not only with controls but also with patients without complications: 0.56±0.06 mm vs. 0.47±0.03 mm (p=0.0001). Adhesion molecule levels were not changed in patients with retinopathy. Higher IMT was found in adolescents with diabetic retinopathy in comparison with patients without complications, which may suggest that macrovascular changes are more advanced in these patients than in their diabetic peers without retinopathy.

Generation of Functional T-Regulatory Cells in Children with Metabolic Syndrome

Recent research implies a role of decreased number and/or function of T-regulatory cells (Tregs) in low-grade inflammation associated with obesity and atherosclerosis. The enhancement of atheroprotective immunity by the expansion of Tregs could serve as a therapeutic strategy in obesity-related immunological disturbances. The aim of our study was an attempt to generate Treg cells in children with risk factors for the development of cardiovascular disease and to compare the results to those obtained in healthy subjects. The study group consisted of 30 children with metabolic syndrome (MS) and 30 controls. Conventional CD4+CD25− cells separated from the peripheral blood were converted into Treg cells with the use of CD3/CD28 antibodies and interleukin (IL)-2/transforming growth factor (TGF)-β stimulation. The expression of critical Treg molecules and cytokines was assessed at mRNA and protein levels. The percentages of Treg cells in the peripheral blood were significantly lower in the children with MS compared to the healthy subjects. After the culture with CD3/CD28 and IL-2/TGF-β we detected a significant increase in the expression of Tregs marker transcription factor FoxP3. The Tregs induced from the children with MS varied from the ones obtained in the controls in the expression of some molecules at mRNA level (e.g. IL-27, LGAL, KLF10 and NRP1) yet not in proliferation studies. For the first time, we have demonstrated the possibility of generating functional Treg cells in children with MS. The results of our study could be used in the design of therapeutic interventions in obesity associated immunologic disturbances.

Endothelial progenitor cells as a new marker of endothelial function with respect to risk of cardiovascular disorders

The discovery of endothelial progenitor cells (EPC), over a decade ago, has refuted the previous belief that vasculogenesis only occurs during embryogenesis. The results of several studies revealed altered number and impaired function of EPC in hyperlipidemia, hypertension, diabetes, obesity as well as in rheumatoid arthritis. The population of developmental age is characterized by higher counts of EPC compared to adults. However, among young patients with chronic disorders that affect the vascular system, the number of EPC decreases. The reduced circulating concentration of EPC has become a surrogate marker of endothelial function and has been implicated in the pathogenesis of many vascular diseases. This article aims to review the biology and pathophysiology of EPC in the conditions of cardiovascular risk factors. The potential possibilities of increasing EPC number and function as well as the use of EPC in the treatment of vascular pathology will also be discussed.

Cardiovascular risk in nonobese hypertensive adolescents: a study based on plasma biomarkers and ultrasonographic assessment of early atherosclerosis.

The objective of this study was to investigate the vascular status, left-ventricular mass and biomarkers of endothelial activation in hypertensive (HT) adolescents, with particular attention to comparing nonobese with obese patients. Seventy-nine newly diagnosed HT adolescents aged 15.1±2.1 years (divided into 34 nonobese and 45 obese) were compared with 35 healthy volunteers. Intima–media thickness (IMT), flow-mediated dilation (FMD) and left-ventricular mass index (LVMi) were determined using ultrasound. Adhesion molecules and inflammatory interleukins (ILs), together with lipids and insulin resistance (HOMA), were also studied. HT obese adolescents had higher triglycerides, HOMA, and elevated levels of interleukin-6, tumor necrosis factor-α, soluble intercellular adhesion molecule-1 and soluble E-selectin compared with controls and nonobese HT patients. FMD was lower in HT groups (8.5±4.5% in nonobese, P=0.004; 8.1±4.9%, P=0.01 in obese vs 12.5±4.9%; in control), and IMT was higher (0.52±0.06 mm, P<0.001 in nonobese; 0.54±0.05 mm, P<0.001 in obese vs 0.42±0.05 mm in control). Higher LVMi was found in both HT groups, with the highest value in the nonobese group being 37.8±5.3 g m−2.7 vs 28.4±5.3 g m−2.7 in controls (P=0.003). In conclusion, nonobese HT adolescents had the same early cardiovascular deteriorations assessed ultrasonographically as their obese HT peers, although metabolic alterations and endothelial activation measured as plasma biomarkers were more pronounced in obese individuals. The potential mechanisms of early atherosclerosis in nonobese HT adolescents need further evaluation in prospective studies because these factors may differ considerably from those found in young obese individuals with HT.

Subclinical Cardiovascular System Changes in Obese Patients with Juvenile Idiopathic Arthritis

Objective. We aimed to determine the prevalence of excess body mass in juvenile idiopathic arthritis (JIA) children and to investigate the influence of obesity into the early, subclinical changes in cardiovascular system in these patients. Methods. Fifty-eight JIA patients, aged median 13 years, were compared to 36 healthy controls. Traditional cardiovascular risk factors and inflammatory markers (hsCRP, IL-6, TNFα, adiponectin) were studied together with IMT (intima-media thickness), FMD (flow mediated dilation), and LVMi (left ventricle mass index) as surrogate markers of subclinical atherosclerosis. Results. Thirteen JIA children (22%) were obese and had increased systolic blood pressure, cholesterol, triglycerides, insulin, HOMA, hsCRP, and IL-6 compared to nonobese JIA and controls. FMD was decreased compared to nonobese JIA and controls, whereas IMT and LVMi were increased. In multivariate regression analysis, TNFα, SDS-BMI, and systolic blood pressure were independent predictors of early CV changes in JIA. Conclusions. Coincident obesity is common in JIA children and is associated with insulin resistance, dyslipidemia, and increased levels of inflammatory markers leading to early changes in cardiovascular system. Thus, medical care of children with JIA should include strategies preventing cardiovascular disease by maintenance of adequate body weight.

Decreased CD127 Expression on CD4+ T-Cells and Elevated Frequencies of CD4+CD25+CD127 T-Cells in Children with Long-Lasting Type 1 Diabetes

Pathobiology of type 1 diabetes (T1D) is predominantly associated with T-cell-related actions. Homeostasis of majority of T-cells is critically dependent on signals mediated by CD127 (interleukin-7 receptor, IL-7R). In contrast, regulatory T-cells express very little CD127 and thereby may be delineated by CD4+CD25+CD127− phenotype. Here we aimed to analyze CD127 expression on CD4+ and CD8+ T-cells and enumerate CD4+CD25+CD127− T-cells in long-lasting T1D. T-cells were analyzed by flow cytometry and immunologic data were correlated with vascular, metabolic, and inflammatory parameters. We demonstrated significantly decreased CD127 levels on CD4+, but not CD8+, T cells in T1D pediatric patients. Interestingly, frequencies of CD4+CD25+CD127− T-cells were significantly enhanced in T1D children and correlated well with frequencies of CD34+CD144+ endothelial progenitor cells and CD4+CD25− T-cells. Levels of CD127 on both CD4+ and CD8+ T-cells in T1D patients were not correlated to each other or HbA1C. Interestingly, however, CD127 levels on CD4+ T-cells were significantly correlated to frequencies of CD4+CD25+CD127− T-cells, whereas CD127 levels on CD8+ T-cells were significantly correlated to concentrations of VEGF and triglycerides. Our data indicate that CD127 expression is differentially modulated on CD4+ and CD8+ T-cells in the course of T1D. Moreover, we demonstrated that, in contrast to recent-onset T1D, long-lasting T1D is associated with enhancement of T-cells with regulatory phenotype.

Elevated levels of Th17 cells in children with central obesity

Abstract Background. It is believed that the recently discovered interleukin 17-producing Th17 cells play a role in the pathogenesis of chronic inflammation in the course of obesity and diabetes. Objectives. The purpose of our study was to complete data on this subject in children. Methods. We assessed Th17 cell levels in the peripheral blood of children diagnosed with central obesity (n = 14) and compared the results with data obtained in patients with newly diagnosed (n = 11) and long-term type 1 diabetes mellitus (n = 18), and in a control group as well (n = 24). Results. (i) Children with central obesity were characterized by higher percentages of Th17 cells as compared to children from the control group; (ii) in the peripheral blood of patients with long-term type 1 diabetes the Th17 cell counts were higher compared to the control group; (iii) total plasma cholesterol concentration correlated positively with Th17/Treg cells ratio; and (iv) among patients with long-term diabetes, disease duration correlated positively with Th17 cell count and Th17/Th1 cell ratio. Conclusion. The results of our study indicate that Th17 cells may be involved in chronic inflammation accompanying obesity and type 1 diabetes mellitus in children.

Endothelial progenitor cell levels in juvenile idiopathic arthritis patients; effects of anti-inflammatory therapies

BackgroundJuvenile idiopathic arthritis (JIA), similarly to other arthritides, can be associated with damage of endothelial layer of which structure and function is dependent on reparative properties of endothelial progenitor cells (EPC). To date, it remained unknown whether EPC numbers are altered in young JIA patients and whether on-going anti-inflammatory therapies could exert positive effects on these progenitor cells.MethodsWe performed a quantitative analysis of EPC numbers in 25 patients diagnosed with JIA according to International League of Associations for Rheumatism (ILAR) criteria [age 11.50 (7.50-15.00) years] in a broad context of inflammatory and cardiovascular parameters as well as different types of anti-inflammatory treatments. 11 healthy children [age 13.00 (11.00-14.00) years] were recruited as a control group.ResultsWe demonstrated that EPC numbers were similar in JIA patients and control subjects (0.02% vs. 0.05%, respectively, p = 0.37). EPC levels in JIA patients were negatively correlated with index of insulin resistance (rho = -0.458, p = 0.021), endogenous insulin (rho = -0.472, p = 0.017), triglyceride (rho = -0.438, p = 0.029) and TNF-alpha levels (rho = -0.446, p = 0.026). Notably, glucocorticoid (GC) therapy, was associated with detection of decreased EPC levels in JIA patients (p = 0.023). In contrast, methothrexate (MTX) and etanercept therapy in JIA patients did not affect EPC levels (p = 0.92 and p = 0.08, respectively).ConclusionsWe found that EPC numbers are maintained at normal levels in JIA patients and are not enhanced by disease-specific anti-inflammatory treatments.