The functions of endothelial progenitor cells were significantly improved after treatment with intravenous immunoglobulin and aspirin in children with Kawasaki disease

Endothelial function and endothelial progenitor cells in systemic lupus erythematosus

The observations that traditional cardiovascular disease (CVD) risk factors fail to fully account for the excessive cardiovascular mortality in patients with systemic lupus erythematosus (SLE) compared with the general population have prompted in-depth investigations of non-traditional, SLE-related risk factors that contribute to cardiovascular complications in patients with SLE. Of the various perturbations of vascular physiology, endothelial dysfunction, which is believed to occur in the earliest step of atherosclerosis, has been extensively investigated for its contribution to CVD risk in SLE. Endothelial progenitor cells (EPCs), which play a crucial part in vascular repair, neovascularization and maintenance of endothelial function, are quantitatively and functionally reduced in patients with SLE. Yet, the lack of a unified definition of EPCs, standardization of the quantity and functional assessment of EPCs as well as endothelial function measurement pose challenges to the translation of endothelial function measurements and EPC levels into prognostic markers for CVD in patients with SLE. This Review discusses factors that contribute to CVD in SLE, with particular focus on how endothelial function and EPCs are evaluated currently, and how EPCs are quantitatively and functionally altered in patients with SLE. Potential strategies for the use of endothelial function measurements and EPC quantification as prognostic markers of CVD in patients with SLE, and the limitations of their prognostication potential, are also discussed.

Low adherence with national travel medicine recommendations in Belgian expatriate children: A retrospective analysis

BACKGROUND

Expatriates (expats) from European countries regularly migrate to low-income countries where infectious diseases are more prevalent. Little evidence exists however on pediatric expatriates' compliance with preventive measures related to infectious diseases. This study aims to evaluate compliance in Belgian expat-children.

METHODS

Data of 135 Belgian expat-children, visiting the Institute of Tropical Medicine (Antwerp, Belgium), were collected from clinical notes, laboratory results and from a web-based immunization-register. Information on routine vaccinations, yellow fever, hepatitis A, rabies, typhoid fever, meningococcal ACW₁₃₅Y, Japanese encephalitis, BCG vaccine and anti-malaria chemoprophylaxis was collected.

RESULTS

Overall, 87% of expat-children were up-to-date with their routine vaccinations. Although all children were eligible for hepatitis A, typhoid and rabies vaccination, only 8-21% were fully vaccinated. Only 29 and 61% of eligible children were vaccinated against meningococcal (ACW₁₃₅Y) or yellow fever respectively. Finally, only 10% of children who lived in malaria-endemic-areas, reported chemoprophylaxis-use.

CONCLUSION

Although routine vaccination coverage in expat-children seems adequate, additional preventive measures are often needed. Whether this is due to lack of high-quality health care-access, fear of side-effects or insufficient knowledge about the risks/available preventive measures, remains elusive. Nevertheless, expats seem to constitute a separate risk-group for infectious diseases and destination-related health issues.

Methods to evaluate arterial structure and function in children - State-of-the art knowledge

BACKGROUND

With increasing rates of hypertension, obesity, and diabetes in the pediatric population, wide available, and reproducible methods are necessary to evaluate arterial structure and function in children and adolescents.

METHODS

MEDLINE/Pubmed was searched for articles published in years 2012-2017 on methodology of, current knowledge on, and limitations of the most commonly used methods to evaluate central, proximal and coronary arteries, as well as endothelial function in pediatric patients.

RESULTS

Among 1528 records screened (including 1475 records from years 2012 to 2017) 139 papers were found suitable for the review. Following methods were discussed in this review article: ultrasound measurements of the intima-media thickness, coronary calcium scoring using computed tomography, arterial stiffness measurements (pulse wave velocity and pulse wave analysis, carotid artery distensibility, pulse pressure, and ambulatory arterial stiffness index), ankle-brachial index, and methods to evaluate vascular endothelial function (flow-mediated vasodilation, peripheral arterial tonometry, Doppler laser flowmetry, and cellular and soluble markers of endothelial dysfunction).

CONCLUSIONS

Ultrasonographic measurement of carotid intima-media thickness and measurement of pulse wave velocity (by oscillometry or applanation tonometry) are highly reproducible methods applicable for both research and clinical practice with proved applicability for children aged ≥6 years or with height ≥120cm. Evaluation of ambulatory arterial stiffness index by ambulatory blood pressure monitoring is another promising option in pediatric high-risk patients. Clearly, further studies are necessary to evaluate usefulness of these and other methods for the detection of subclinical arterial damage in children.

Aspirin Inhibits Degenerative Changes of Aneurysmal Wall in a Rat Model

Aneurysmal subarachnoid hemorrhage still has a high mortality and morbidity despite notable advances in surgical approaches to cerebral aneurysm (CA). We examined the role of aspirin in vascular inflammation and degeneration. CA was induced in male Sprague-Dawley rats by ligating left common carotid artery and bilateral posterior renal arteries with or without aspirin treatment. The right anterior cerebral artery/olfactory artery (ACA/OA) bifurcations were stripped and assessed morphologically after Verhoeff's Van Gieson staining. Blood sample was obtained to examine circulating CD34(+) CD133(+) endothelial progenitor cells (EPCs), platelet aggregation and platelet counts. Macrophages infiltration in aneurysmal wall was evaluated by immunohistochemistry. Expression of matrix metalloproteinase-2 and 9 (MMP-2 and 9), nuclear factor kappa B (NF-κB), macrophage chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) was examined by RT-PCR. 2 months after CA induction, surgically treated rats manifested aneurysmal degeneration in ACA/OA bifurcations. Aspirin-treated rats exhibited a significant decrease in degradation of internal elastic lamina (IEL), medial layer thinning, CA size and macrophages infiltration with reduced expression of MMP-2 and 9 compared with rats in the CA group. RT-PCR demonstrated that the upregulation of NF-κB, MCP-1 and VCAM-1 after CA induction was reversed by aspirin treatment. Aspirin treatment following CA induction increased circulating EPCs to near control levels and reduced platelet aggregation without changing platelet counts. The evidence suggested that aspirin significantly reduced degeneration of aneurysm walls by inhibiting macrophages-mediated chronic inflammation and mobilizing EPCs.

Improving cardiovascular outcomes in rheumatic diseases: therapeutic potential of circulating endothelial progenitor cells

Patients with Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE) have a significantly increased risk of cardiovascular disease (CVD). The reason for this is unclear but may be due, at least in part, to the failure of endothelial repair mechanisms. Over the last 15 years there has been much interest in the mechanisms of endothelial renewal and its potential as a therapy for CVD. In the circulation there are two distinct populations of cells; myeloid angiogenic cells (MACs) which augment repair by the paracrine secretion of angiogenic factors, and outgrowth endothelial cells (OECs) which are true endothelial progenitor cells (EPCs) and promote vasculogenesis by differentiating into mature endothelium. There are marked abnormalities in the number and function of these cells in patients with RA and SLE. Inflammatory cytokines including interferon-alpha (IFNα) and tumour-necrosis factor alpha (TNFα) both impair MAC and OEC function ex vivo and may therefore contribute to the CVD risk in these patients. Whilst administration of mononuclear cells, MACs and other progenitors has improved cardiovascular outcomes in the acute setting, this is not a viable option in chronic disease. The pharmacological manipulation of MAC/OEC function in vivo however has the potential to significantly improve endothelial repair and thus reduce CVD in this high risk population.

The circulating level of endothelial progenitor cells after transcatheter closure of congenital heart disease in children

Data have shown that circulating endothelial progenitor cells (EPCs) closely correlate with the vascular endothelial layer state. The present study was designed to describe the evolution of EPCs in children before and 24 h after transcatheter closure surgery for occluding congenital heart disease. Three groups of patients were studied: the transcatheter closure of atrial septal defect (ASD) group (group 1), the transcatheter closure of patent ductus arteriosus (PDA) group (group 2), and the transcatheter closure of ventricular septal defect (VSD) group (group 3). The circulating EPC level was detected using flow cytometry measuring CD34 and kinase insert receptor double-positive mononuclear cells. The concentration of vascular endothelial growth factor (VEGF) was assessed by enzyme-linked immunosorbent assay. The fluoroscopy time was correctly recorded during the surgery. All of the data were collected before and 24 h after surgery. EPC level and VEGF concentration did not change significantly before and at 24 h after surgery in groups 1 and 2. In group 3, the level of circulating EPCs and VEGF concentration increased significantly 24 h after surgery. The fluoroscopy time in group 3 was significantly longer than in groups 1 and 2. The increased volume of EPCs and VEGF were positively correlated in group 3. Our results showed that transcatheter closure of PDA and ASD in children does not lead to increased circulating level of EPCs. Transcatheter closure of VSD may result in vascular endothelium injury as indicated by increased circulating EPC level.

Endothelial progenitor cells in cardiovascular disease and chronic inflammation: from biomarker to therapeutic agent

The discovery of endothelial progenitor cells in the 1990s challenged the paradigm of angiogenesis by showing that cells derived from hematopoietic stem cells are capable of forming new blood vessels even in the absence of a pre-existing vessel network, a process termed vasculogenesis. Since then, the majority of studies in the field have found a strong association between circulating endothelial progenitor cells and cardiovascular risk. Several studies have also reported that inflammation influences the mobilization and differentiation of endothelial progenitor cells. In this review, we discuss the emerging role of endothelial progenitor cells as biomarkers of cardiovascular disease as well as the interplay between inflammation and endothelial progenitor cell biology. We will also review the challenges in the field of endothelial progenitor cell-based therapy.