Early atherosclerosis in childhood: diagnostic approaches and therapeutic strategies

Cardiorespiratory Fitness, Fat Mass, and Cardiometabolic Health with Endothelial Function, Arterial Elasticity, and Stiffness

PURPOSE

This study aimed to determine whether estimated cardiorespiratory fitness (CRF), fat mass (FM), lean mass (LM), and adiponectin bidirectionally associate with arterial function and structure and if CRF mediates the relationship between cardiometabolic health and arterial outcomes in 9- to 11-yr-old children drawn from the Avon Longitudinal Study of Parents and Children birth cohort, United Kingdom.

METHODS

Brachial artery flow-mediated dilation (FMD), distensibility coefficient (DC), and carotid-radial pulse wave velocity (PWV) were measured by ultrasonography; CRF was measured during the submaximal ergometer test; total FM, trunk FM, and LM were measured by dual-energy x-ray absorptiometry; plasma adiponectin was measured by enzyme assay; and cardiometabolic health was computed based on the International Diabetes Federation criteria for diagnosing metabolic syndrome. We tested bidirectionality by including CRF, FM, LM, and adiponectin as exposures and FMD, DC, and PWV as outcomes, alternatively.

RESULTS

Among 5566 participants (2816 (51%) girls; median age, 9.75 yr), CRF per body mass0.21 was directly related to DC (β (95% confidence interval) = 0.004 (<0.0001 to 0.008); P = 0.046), whereas CRF per LM0.54 was inversely associated with PWV (-0.034 (-0.063 to -0.003); 0.032) after adjusting for covariates. These associations remained in bidirectional analyses. Total FM, trunk FM, and LM were bidirectionally and positively associated with FMD and DC. Total FM and trunk FM but not LM had bidirectional and inverse associations with PWV. Adiponectin was not related to FMD, DC, or PWV. CRF partially mediated the associations of cardiometabolic health with FMD (1.5% mediation), DC (12.1% mediation), and PWV (3.5% mediation).

CONCLUSIONS

Associations of poor cardiometabolic health with adverse arterial structure and function in childhood may be mitigated by increasing CRF. Higher CRF was associated with better arterial structure whereas higher total FM and trunk FM were associated with better arterial function and structure. In the reverse analysis, healthy arterial structure and function were independently associated with increased total FM and trunk FM, suggesting an "arterial paradox."

MicroRNAs in Cardiovascular Disease: Perspectives and Reality

Since the discovery of the first noncoding RNA decades ago, the transcriptomics evolution has made a great leap reaching to the detection and recognition of microRNAs (miRNAs) in the early 1990s. Thereafter, numerous miRNAs were reported in different species, with a great body of literature focusing on their role in human health and in pathophysiological processes. miRNAs play a significant role in the cardiovascular system, not only in physiology and normal development but also in disease processes and evolution. Further studies on miRNAs have highlighted their participation in several expressions of cardiovascular disease, such as atherosclerosis, acute and chronic syndromes of coronary artery disease, heart failure, and cardiac arrhythmias. To date, the challenge remains to understand the underlying mechanisms of miRNAs that drive their expression profile so as to use them as innovative diagnostic tools or therapeutic targets in cardiovascular disease.

Circulating microRNAs in cardiovascular diseases: from biomarkers to therapeutic targets

microRNAs (miRNAs) are a class of conserved, short, non-coding RNAs that have important and potent capacities to regulate gene expression at the posttranscriptional level. In the past several years, the aberrant expressions of miRNAs in the cardiovascular system have been widely reported, and the crucial roles of some special miRNAs in heart development and pathophysiology of various cardiovascular diseases have been gradually recognized. Recently, it was discovered that miRNAs are presented in peripheral circulation abundantly and stably. This has raised the possibility of using circulating miRNAs as biomarkers for diseases. Furthermore, some studies demonstrated that circulating miRNAs may serve as novel extracellular communicators of cell-cell communication. These discoveries not only reveal the functions of circulating miRNAs in cardiovascular system but also inform the development of miRNAs therapeutic strategies. In this review, we discuss the potential roles of circulating miRNAs in a variety of cardiovascular diseases from biomarkers to therapeutic targets to clearly understand the roles of circulating miRNAs in cardiovascular system.

[Centile values for serum lipids in Colombian adolescents]

OBJECTIVE

To assess age- and sex-specific percentile baseline data for total cholesterol (TC), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) in Colombian children and adolescents aged 10 to 17 years.

PATIENTS AND METHODS

A cross-sectional, descriptive study was conducted on 1,773 children and adolescents. Each participant underwent a fasting measurement to quantify TC, HDL-C, and TG levels using enzymatic-colorimetric methods. Smoothed age- and sex-specific 5(th), 25(th), 50(th), 75(th), 90(th) and 95(th) percentile values where derived using LMS regression (Least Mean Square) using the statistical package Growth Analyzer.

RESULTS

Overall, males had lower serum TC and TG levels as compared to females. P95 of TG and TC was higher in males aged 10 to 14 years as compared to females, while HDL-C levels were similar in both sexes.

CONCLUSIONS

Percentile values will help classify children and adolescents as compared to other populations based on this health indicator.

Importance of plasma N-terminal pro B-type natriuretic peptide, epicardial adipose tissue, and carotid intima-media thicknesses in asymptomatic obese children

This study aimed to analyze the variations of N-terminal pro B-type natriuretic peptide, epicardial adipose tissue thickness, and carotid intima-media thickness in childhood obesity. The study participants consisted of 50 obese children in the study group and 20 nonobese children referred for evaluation of murmurs who proved to have an innocent murmur and were used as control subjects. All the subjects underwent transthoracic echocardiographic examination for determination of left ventricular systolic function and mass index, myocardial tissue rates, and myocardial performance index. Epicardial adipose tissue thickness and carotid intima-media thickness also were measured during echocardiography. Serum N-terminal pro B-type natriuretic peptide levels were measured at the time of evaluation. The left ventricle mass index was 40.21 + or - 10.42 g/m(2) in the obese group and 34.44 + or - 4.51 g/m(2) in the control group (p > 0.05). The serum N-terminal pro B-type natriuretic peptide level was 109.25 + or - 48.53 pg/ml in the study group and 51.96 + or - 22.36 pg/ml and in the control group (p = 0.001). The epicardial adipose tissue thickness was 5.57 + or - 1.45 mm in the study group and 2.98 + or - 0.41 mm in the control group (p = 0.001), and the respective carotid intima-media thicknesses were 0.079 + or - 0.019 cm and 0.049 + or - 0.012 cm (p = 0.001). The left ventricular systolic and diastolic functions showed no statistically significant correlations with N-terminal pro B-type natriuretic peptide levels, carotid intima-media thickness, or epicardial adipose tissue thickness values. The results show that measurement of serum N-terminal pro B-type natriuretic peptide level, carotid intima-media thickness, and epicardial adipose tissue thickness in asymptomatic obese children is not needed.

Early markers of cardiovascular dysfunction in young girls affected by Cushing's syndrome before and after successful cure

BACKGROUND

even after successful surgical cure, Cushing's Syndrome (CS) may induce cardiovascular (CV) diseases including hypertension, or elicit onset of CV risk factors, such as obesity.

OBJECTIVES

to evaluate some early markers of CV dysfunction in adolescent girls before and after successful surgical cure of CS; to compare after surgery data with those of a control group (C) of healthy young girls.

METHODS

23 girls affected by CS were enrolled (range: 11-17 years; mean: 14.3 +/- 1.7 years). Epicardial fat thickness (EFT), intima-media thickness (IMT), N-terminal pro B-type natriuretic peptide (NT-proBNP) were assessed; transthoracic echocardiogram coupled with Tissue Doppler imaging (TDI) was performed. RESULTS (CS before surgery vs. CS after surgery): EFT (p < 0.05). (CS after surgery vs. C): EFT (p = 0.0001); IMT (p = 0.0001); NT-proBNP (p = 0.0001). TDI: isovolumetric relaxation time (p = 0.001); isovolumetric contraction time (p = 0.001); myocardial performance index (p = 0.001). Significant correlations: NT-proBNP with IRT (r = 0.45, p = 0.026 ), ICT (r = 0.47, p = 0.028), and myocardial performance index (r = 0.51, p = 0.0032).

CONCLUSIONS

important structural and functional modifications of heart and vessels are present in young female CS despite successful surgical cure, even in paediatric age. It underlines their significantly higher cardiovascular risk. Our findings confirm that EFT, IMT, NT-proBNP and TDI diastolic parameters, not previously tested in paediatric CS, are early markers of cardiovascular dysfunction. Because of its relationship with TDI, the assessment of NT-proBNP proves to be the best marker in detecting a cardiovascular dysfunction in this specific population.

Determinants of vascular phenotype in a large childhood population: the Avon Longitudinal Study of Parents and Children (ALSPAC)

AIMS

To assess the feasibility and reproducibility of non-invasive vascular assessment in a childhood population setting and identify the determinants of vascular phenotype in early life.

METHODS AND RESULTS

We studied 7557 children (age 9.8-12.3 years) participating in the Avon Longitudinal Study of Parents and Children (ALSPAC). Six research technicians underwent a 5-month training protocol to enable study of brachial artery endothelial function by flow-mediated dilatation (FMD) and arterial stiffness by carotid to radial pulse wave velocity (PWV) and brachial distensibility [distensibility coefficient (DC)]. Reproducibility studies were performed at the beginning, the middle, and the end of the study. A blinded repeat evaluation of a random selection of 3% of the cohort was also undertaken throughout the study. The effect of anthropometric and environmental factors on each measure was examined. Successful measures were obtained in 88, 95, and 87% of the studied children for FMD, PWV, and DC, respectively. The coefficients of variation between technicians for FMD, PWV, and DC were 10.5, 4.6, and 6.6% at the beginning of the study and reached 7.7, 4.1, and 10% at the end. Baseline vessel diameter and gender were important determinants of all the vascular measures, with a small effect of room and skin temperatures on FMD and PWV. Boys consistently had lower FMD and DC and higher PWV measures (P < 0.01 for all).

CONCLUSION

Reproducible, high-quality assessments of vascular structure and function in children can be made on a large scale in field studies by suitably trained non-specialist operators. This study provides an invaluable resource for assessing the impact of early influences, genetic, and environmental factors on arterial phenotype.

The factor V G1691A, factor V H1299R, prothrombin G20210A polymorphisms in children with family history of premature coronary artery disease

Atherosclerosis, the major cause of coronary artery disease (CAD), has a very long asymptomatic development phase, which begins in childhood. In this study, we describe the factor V G1691A, factor V H1299R and prothrombin G20210A gene polymorphisms in children with a family history of premature CAD. Evidence of these polymorphisms in these children may predict the probability of having atherosclerosis in the future. Our study included a total of 140 children, 72 males and 68 females between the ages of 4.9 and 15.7 years. Among these children, 73 had a parental history of premature CAD and the remaining 67 belonged to our control group. The participants were screened for the mutations factor V G1691A, factor V H1299R and prothrombin G20210A by polymerase chain reaction amplified DNA products with specific oligonucleotide probes. Our results suggested that frequencies of the mutated allele of factor V G1691A and prothrombin G20210A are higher in children with a parental history of premature CAD. In conclusion, factor V G1691A and prothrombin G20210A polymorphisms which were detected in higher frequencies in children with a parental history of premature CAD may indicate a risk for developing atherosclerosis and might be useful in screening for CAD in children; however, large population-based research is necessary to investigate further genetic risk assessment for CAD.

Is Helicobacter pylori related to endothelial dysfunction during childhood?

BACKGROUND

Helicobacter pylori infection has been proposed to have a role in the development of atherosclerosis preceded by endothelial dysfunction. The aim of the present study was to determine if a relationship exists between H. pylori infection in childhood and endothelial dysfunction and level of high-sensitivity C-reactive protein (hsCRP).

METHODS

Between October 2003 and November 2004, 28 subjects who were anti-H. pylori IgG-positive and 25 who were anti-H. pylori IgG-negative were included in the study. Mean ages of the H. pylori-positive and negative groups were not significantly different. Endothelial functions were evaluated on Doppler ultrasonography of the brachial artery. Percent ratio of the change in systolic diameter during hyperemic phase to the basal diameter was evaluated. Each subject's serum was tested for hsCRP, homocysteine and lipids.

RESULTS

Percent ratio of the change in systolic diameters during hyperemic phase to the basal diameter was not significantly different between the H. pylori-negative and -positive groups (P > 0.29). Mean levels of hsCRP were also not significantly different (1.48 +/- 1.8 g/dL vs 2.35 +/- 3.33 g/dL; P > 0.24). Similarly, serum levels of lipids and homocysteine were not significantly different (P > 0.05 for all lipids).

CONCLUSIONS

Non-invasive techniques used in the present study were not indicative of early findings of atherosclerosis in H. pylori infection during childhood. Further studies are required to evaluate the relationship between early endothelial dysfunction and H. pylori infection in children with cardiovascular risk factors.

Inulin attenuates atherosclerosis in apolipoprotein E-deficient mice

Effects of different inulin-type fructan fractions were studied on atherosclerotic plaque formation in male apo E-deficient mice. Thirty-two mice were randomly divided into four groups and received either a semi-purified sucrose-based diet (control group), or diets in which sucrose was replaced in part by various inulin-type fructans (10 g/100 g): long-chain inulin, oligofructose, or an oligofructose-enriched inulin for 16 weeks. The presence of atherosclerotic plaques was assessed by histomorphometry in the aortic sinus. The apo E-deficient mice fed long-chain inulin or an oligofructose-enriched inulin had about 35 % and 25 % less atherosclerotic lesion area compared with the control group, respectively. Feeding long-chain inulin significantly reduced plasma cholesterol concentrations (P<0.001), and the three inulin-type fructans reduced triacylglycerol (TAG) concentrations compared with the control group (P<0.001). Both the long-chain inulin and an oligofructose-enriched inulin significantly lowered hepatic cholesterol concentrations compared with the control diet (P<0.05). Hepatic TAG concentrations were significantly lower in all three groups fed the fructan-supplemented diets v. the control group (P<0.0001). The results of the present study suggest that inhibition of atherosclerotic plaque formation is more potent in the presence of long-chain inulin, either alone or in combination with oligofructose (an oligofructose-enriched inulin), and that this probably is related to changes in lipid metabolism.