Decreased vitamin D levels in the pediatric population after COVID-19 lockdown.

BACKGROUD: SARS-Cov2 infection began to spread worldwide since December 2019; on March 2020, the World Health Organization characterized its related disease, named COVID-19, as a pandemic. In Italy, to contain the spread of infection a severe lockdown in the spring 2020 was instituted. Other less severe restrictions were imposed in the winter 2020-2021 and in the spring 2021. The containment measures caused a series of consequences for the population and, in particular, for children and adolescents that presented psychophysical problems. The aim of this manuscript is to investigate the serum levels of vitamin D in children and adolescents before, during and after the lockdown consequent to COVID-19 pandemic. METHODS: This is a retrospective cross-sectional study, including all children and adolescents between 1 to 18 years referring to the Pediatric Endocrinology Service of the University Hospital of Verona, Italy, between January 2019 and December 2021. All patients affected by clinical conditions that involve vitamin D metabolism or assuming vitamin D supplementation were excluded. RESULTS: In total, 491 children (36.7% males and 63.3% females) were enrolled in this study. The vitamin D levels decreased over time: 28.3 ± 10.2 ng/mL in 2019; 28.2 ± 11.4 ng/mL in 2020 and 24.9 ± 10.1 ng/mL in 2021 (p < 0.05). The vitamin D levels are significant higher in summer and in autumn in comparison with the levels of winter and spring, regardless of the examined years. CONCLUSIONS: The measures adopted to contain the COVID-19 pandemic led to a reduction of serum levels of vitamin D in pediatric population, probably due to the reduced solar exposure. This may have severe consequences on the bone metabolism of those children who did not present optimal vitamin D levels even before the lockdown. Therefore, an adequate supplementation of vitamin D is necessary from the end of fall to the beginning of spring (November-April) in all children and adolescents living in Northern Italy.

Vitamin D and Osteogenesis Imperfecta in Pediatrics.

Osteogenesis Imperfecta (OI) is a heterogeneous group of inherited skeletal dysplasias characterized by bone fragility. The study of bone metabolism, in these disease, is problematic in terms of clinical and genetic variability. The aims of our study were to evaluate the importance of Vitamin D levels in OI bone metabolism, reviewing studies performed on this topic and providing advice reflecting our experience using vitamin D supplementation. A comprehensive review on all English-language articles was conducted in order to analyze the influence of vitamin D in OI bone metabolism in pediatric patients. Reviewing the studies, contradictory data were found on the relationship between 25OH vitamin D levels and bone parameters in OI, and in several studies the baseline levels of 25OH D were below the threshold value of 75 nmol/L. In conclusion, according to the literature and to our experience, we highlight the importance of adequate vitamin D supplementation in children with OI.

Supportive treatment of vascular dysfunction in pediatric subjects with obesity: the OBELIX study.

INTRODUCTION: Overweight or obese children develop abnormal endothelial cell dysfunction and arterial intima-media thickening with increased vasomotor tone and inflammation. Curcumin, resveratrol, zinc, magnesium, selenium, and vitamin D have shown beneficial effects on endothelial function. We test, among overweight and obese pediatric subjects, the effects on the endothelium of a combination of curcumin, resveratrol, zinc, magnesium, selenium, and vitamin D. METHODS: Forty-eight subjects (6-17 years) were randomized into two groups (placebo vs treatment) attended three visits at 0, 3, and 6 months (±15 days). Endothelial function was assessed by means of a post-occlusive release hyperemic (PORH) test for estimation of delta flow (DF) and hyperemic AUC index, and a heat provocation test (HPT) to measure DF HPT (DFHPT). RESULTS: Significant DF difference was noted at 6 months in both groups (p < 0.001). Overall time trend was significantly different between baseline, 3 months, and 6 months both in placebo (p < 0.05) and treatment (p < 0.001) groups and their comparison (p < 0.001). No differences were noted in hyperemic AUC index (3 and 6 months), whilst there were significant differences in time trends of rreatment (p < 0.001) and placebo (p < 0.05) groups and their comparison (p < 0.001). DFHPT difference between groups was significant at 3 and 6 months (p < 0.05). The overall time trend was significant exclusively in Treatment group between 3 and 6 months (p < 0.05). Correlation with anthropometrics was found for DF and body mass index (r = 0.677 6 months, p < 0.05), as well as for hyperemic AUC index and males (r = 0.348, p < 0.05), while DFHPT showed no correlation. CONCLUSION: Curcumin, resveratrol, zinc, magnesium, selenium, and vitamin D appear to be promising in enhancing endothelial function by improvement of both DF in the PORH test and DF in the HPT, lowering the risk of developing cardiovascular diseases in overweight and obese pediatric subjects.

Bone Marrow Foot Oedema in Adolescents: The Role of Vitamin D.

BACKGROUND: Bone marrow oedema (BMO) in children/adolescents is a rare clinical condition without an etiologic cause. It is associated with typical increased signal intensity on T2-weighted magnetic resonance images (MRI) and an increase in bone turnover in which vitamin D plays a pivotal role. No treatment guidelines for these young patients are to date available. METHODS: We performed a retrospective study in a pediatric setting of 13 patients with diagnosis of primary BMO of the foot on the basis of clinical and radiological findings. Data collection included sex, age, patient history, symptoms at presentation, clinical examination, laboratory bone turnover markers, vitamin D levels, MRI, treatment, and outcome. RESULTS: Vitamin D deficiency or insufficiency was found in 76.9% of cases. All patients were treated with adequate vitamin D daily intake, a short course of analgesic therapy, physical therapy, avoiding detrimental feet and ankle immobilization. All fully recovered in 3-month lag period. CONCLUSIONS: Our data highlight that environmental factors, such as underestimated articular or bone microtraumatisms, as well as joint hyper mobility, in a bone turnover milieu of vitamin D deficiency could be the cause of this clinical conditions. Adequate vitamin D supplementation, associated with physical and analgesic therapy, is crucial in the management of BMO.

Individual fatty acids in erythrocyte membranes are associated with several features of the metabolic syndrome in obese children.

PURPOSE: Obesity leads to the clustering of cardiovascular (CV) risk factors and the metabolic syndrome (MetS) also in children and is often accompanied by non-alcoholic fatty liver disease. Quality of dietary fat, beyond the quantity, can influence CV risk profile and, in particular, omega-3 fatty acids (FA) have been proposed as beneficial in this setting. The aim of the study was to evaluate the associations of individual CV risk factors, characterizing the MetS, with erythrocyte membrane FA, markers of average intake, in a group of 70 overweight/obese children. METHODS: We conducted an observational study. Erythrocyte membrane FA were measured by gas chromatography. Spearman correlation coefficients (rS) were calculated to evaluate associations between FA and features of the MetS. RESULTS: Mean content of Omega-3 FA was low (Omega-3 Index = 4.7 ± 0.8%). Not omega-3 FA but some omega-6 FA, especially arachidonic acid (AA), were inversely associated with several features of the MetS: AA resulted inversely correlated with waist circumference (rS = - 0.352), triglycerides (rS = - 0.379), fasting insulin (rS = - 0.337) and 24-h SBP (rS = - 0.313). Total amount of saturated FA (SFA) and specifically palmitic acid, correlated positively with waist circumference (rS = 0.354), triglycerides (rS = 0.400) and fasting insulin (rS = 0.287). Fatty Liver Index (FLI), a predictive score of steatosis based on GGT, triglycerides and anthropometric indexes, was positively correlated to palmitic acid (rS = 0.515) and inversely to AA (rS = - 0.472). CONCLUSIONS: Our data suggest that omega-6 FA, and especially AA, could be protective toward CV risk factors featuring the MetS and also to indexes of hepatic steatosis in obese children, whereas SFA seems to exert opposite effects.

Possible Role of CYP450 Generated Omega-3/Omega-6 PUFA Metabolites in the Modulation of Blood Pressure and Vascular Function in Obese Children.

Obesity is often accompanied by metabolic and haemodynamic disorders such as hypertension, even during childhood. Arachidonic acid (AA) is metabolized by cytochrome P450 (CYP450) enzymes to epoxyeicosatrienoic acids (EETs) and 20-hydroxyeicosatetraenoic acid (20-HETE), vasoactive and natriuretic metabolites that contribute to blood pressure (BP) regulation. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) omega-3 polyunsaturated fatty acids may compete with AA for CYP450-dependent bioactive lipid mediator formation. We aimed at investigating the role of AA, EPA and DHA and their CYP450-dependent metabolites in BP control and vascular function in 66 overweight/obese children. Fatty acid profile moderately correlated with the corresponding CYP450-derived metabolites but their levels did not differ between children with normal BP (NBP) and high BP (HBP), except for higher EPA-derived epoxyeicosatetraenoic acids (EEQs) and their diols in HBP group, in which also the estimated CYP450-epoxygenase activity was higher. In the HBP group, EPA inversely correlated with BP, EEQs inversely correlated both with systolic BP and carotid Intima-Media Thickness (cIMT). The DHA-derived epoxydocosapentaenoic acids (EDPs) were inversely correlated with diastolic BP. Omega-3 derived epoxymetabolites appeared beneficially associated with BP and vascular structure/function only in obese children with HBP. Further investigations are needed to clarify the role of omega-3/omega-6 epoxymetabolites in children's hemodynamics.

Bone density in children treated with gonadotropin-releasing hormone analogs for central precocious puberty.

Estrogens, growth hormones and IGFs are essential in the development and growth of the skeleton and for the maintenance of bone mass and density. Treatment of precocious puberty with gonadotropin-releasing hormone analogs (GnRHa), leads to a situation of hypoestrogenism by reducing sex-steroid levels, which, theoretically, may have a detrimental effect on bone mass during pubertal development. A reduction in bone mineral density during GnRHa treatment has been shown, but GnRHa treatment in patients with central precocious puberty does not seem to impair the achievement of normal peak bone mass at adult height. However, calcium supplementation is effective in improving bone densitometric levels and may promote better peak bone mass achievement.