Effect of vitamin C on endothelial function of children with chronic renal failure: An experimental study

Comparison of CIMT and FMD in the Brachial Artery between Children with Acyanotic Congenital Heart Disease and Healthy Controls: A Case-Control Study

Background

Congenital heart disease (CHD), a developmental abnormality of the heart and vessels, is encountered in the pediatric age group frequently. Brachial artery flow-mediated dilation (FMD) and carotid intima-media thickness (CIMT) are indicators of subclinical cardiovascular disease and are used as surrogate measures of subclinical atherosclerosis. The present study aimed to compare CIMT and FMD between children with acyanotic congenital heart disease (ACHD) and healthy controls.

Methods

A case-control study on 50 children with ACHD and 43 healthy individuals was done in Isfahan, Iran, between 2021 and 2022. The case group was selected via non-random sampling, and healthy controls were recruited from the relatives of the patients. A checklist, including age, sex, body mass index, and blood pressure, was filled out for all the participants. Then, FMD and CIMT were measured with brachial and carotid artery ultrasonography.

Results

Fifty children with ACHD and 43 healthy individuals (controls) under 18 years old participated in this study. Of these, 44 (47.3%) were girls and 49 (52.7%) were boys. The mean FMD was significantly higher in the ACHD group than in the control group (0.084±0.027 vs 0.076±0.042; P=0.021; 95% CI, 007 to 0.122;). CIMT was significantly higher in the ACHD group than in the control group (0.39±0.12 vs 0.34±0.1; P=0.037; 95% CI, 0.009 to 0.102;). However, systolic and diastolic blood pressure did not show differences between the groups.

Conclusion

Based on our results, CIMT and FMD assessment may help detect early changes in peripheral vessels associated with atherosclerosis in the future in ACHD. Further studies are needed to confirm our findings.

Endothelial Dysfunction in Chronic Kidney Disease, from Biology to Clinical Outcomes: A 2020 Update

The vascular endothelium is a dynamic, functionally complex organ, modulating multiple biological processes, including vascular tone and permeability, inflammatory responses, thrombosis, and angiogenesis. Endothelial dysfunction is a threat to the integrity of the vascular system, and it is pivotal in the pathogenesis of atherosclerosis and cardiovascular disease. Reduced nitric oxide (NO) bioavailability is a hallmark of chronic kidney disease (CKD), with this disturbance being almost universal in patients who reach the most advanced phase of CKD, end-stage kidney disease (ESKD). Low NO bioavailability in CKD depends on several mechanisms affecting the expression and the activity of endothelial NO synthase (eNOS). Accumulation of endogenous inhibitors of eNOS, inflammation and oxidative stress, advanced glycosylation products (AGEs), bone mineral balance disorders encompassing hyperphosphatemia, high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23), and low levels of the active form of vitamin D (1,25 vitamin D) and the anti-ageing vasculoprotective factor Klotho all impinge upon NO bioavailability and are critical to endothelial dysfunction in CKD. Wide-ranging multivariate interventions are needed to counter endothelial dysfunction in CKD, an alteration triggering arterial disease and cardiovascular complications in this high-risk population.

Crosstalk between Vitamins A, B12, D, K, C, and E Status and Arterial Stiffness

Arterial stiffness is associated with cardiovascular risk, morbidity, and mortality. The present paper reviews the main vitamins related to arterial stiffness and enabling destiffening, their mechanisms of action, providing a brief description of the latest studies in the area, and their implications for primary cardiovascular prevention, clinical practice, and therapy. Despite inconsistent evidence for destiffening induced by vitamin supplementation in several randomized clinical trials, positive results were obtained in specific populations. The main mechanisms are related to antiatherogenic effects, improvement of endothelial function (vitamins A, C, D, and E) and metabolic profile (vitamins A, B12, C, D, and K), inhibition of the renin-angiotensin-aldosterone system (vitamin D), anti-inflammatory (vitamins A, D, E, and K) and antioxidant effects (vitamins A, C, and E), decrease of homocysteine level (vitamin B12), and reversing calcification of arteries (vitamin K). Vitamins A, B12, C, D, E, and K status is important in evaluating cardiovascular risk, and vitamin supplementation may be an effective, individualized, and inexpensive destiffening therapy.