Association Between VDR and CYP24A1 Polymorphisms, Atopic Dermatitis, and Biochemical Lipid and Vitamin D Profiles in Spanish Population: Case-Control Study

BACKGROUND

Atopic dermatitis (AD) is the most prevalent inflammatory skin disorder, characterized by impaired epidermal barrier function and an altered immune response, both of which are influenced by vitamin D deficiency. Single-nucleotide polymorphisms (SNPs) in VDR and CYP24A1 have been previously associated with AD.

OBJECTIVE

We sought to characterize the associations between the VDR and CYP24A1 polymorphisms and the vitamin D and lipid biochemical profile in children diagnosed with AD.

METHODS

A total of 246 participants (143 patients with AD and 103 healthy controls) were enrolled in this study. Genotyping for polymorphisms in VDR (rs2239185, rs1544410, rs7975232, rs2238136, rs3782905, rs2239179, rs1540339, rs2107301, rs2239182, and rs731236) and CYP24A1 (rs2248359 and rs2296241) was performed by allele-specific polymerase chain reaction using integrated fluidic circuit technology. Serum levels of calcium, phosphorus, and vitamin D were measured, and the biochemical lipid profile was determined.

RESULTS

Among VDR SNPs, rs2239182 exerted a protective effect against the development of AD, whereas rs2238136 was identified as a risk factor for AD. The GCC haplotype (rs2239185-G, rs1540339-C, and rs2238136-C) appeared to protect against the development of AD. rs2239182-CC was associated with higher 25(OH)D concentrations, whereas rs2238136-TT, rs2239185-GA, and rs2248359-TT were present in a large proportion of patients with serum vitamin D deficiency. rs2239185-AA, rs2239182-CC, and rs1540339-CC were associated with higher serum total cholesterol; rs2239182-TT was associated with lower low-density lipoprotein cholesterol; and rs2239182-TC with lower high-density lipoprotein cholesterol. Both CYP24A1 SNPs (rs2296241-AA and rs2248359-TT) were associated with higher high-density lipoprotein cholesterol levels.

CONCLUSIONS

The VDR SNP rs2238136 is a risk factor for AD and other SNPs in VDR and CYP24A1, which may lead to alterations in biochemical parameters that influence the risk of AD. Our findings highlight the complex genetic basis to AD and indicate that interrelationships between different genetic factors can lead to alterations in vitamin D metabolism or lipid profiles, which in turn may influence the development of AD.

Immunosenescence and Skin: A State of Art of Its Etiopathogenetic Role and Crucial Watershed for Systemic Implications

Immunosenescence is a complex multifactorial phenomenon consisting of wide-ranging remodeling of the immune system during the life span, resulting in an age-related qualitative-quantitative decline of immune cells and cytokines. A growing body of evidence in the international literature is highlighting the etiopathogenetic role of skin immunosenescence in the onset of various dermatologic conditions. Skin immunosenescence also serves as an interesting watershed for the onset of system-wide conditions in the context of allergic inflammation. Moreover, in recent years, an increasingly emerging and fascinating etiopathogenetic parallelism has been observed between some mechanisms of immunosenescence, both at cutaneous and systemic sites. This would help to explain the occurrence of apparently unconnected comorbidities. Throughout our review, we aim to shed light on emerging immunosenescent mechanisms shared between dermatologic disorders and other organ-specific diseases in the context of a more extensive discussion on the etiopathogenetic role of skin immunosenescence. A promising future perspective would be to focus on better understanding the mutual influence between skin and host immunity, as well as the influence of high inter-individual variability on immunosenescence/inflammaging. This can lead to a more comprehensive "immunobiographic" definition of each individual.

Effects of infant feeding with goat milk formula or cow milk formula on atopic dermatitis: protocol of the randomised controlled Goat Infant Formula Feeding and Eczema (GIraFFE) trial

INTRODUCTION

Atopic dermatitis (AD) is a chronic, inflammatory skin condition significantly affecting quality of life. A small randomised trial showed an approximately one-third lower incidence of AD in goat milk formula-fed compared with cow milk formula-fed infants. However, due to limited statistical power, AD incidence difference was not found to be significant. This study aims to explore a potential risk reduction of AD by feeding a formula based on whole goat milk (as a source of protein and fat) compared with a formula based on cow milk proteins and vegetable oils.

METHODS AND ANALYSIS

This two-arm (1:1 allocation), parallel, randomised, double-blind, controlled nutritional trial shall enrol up to 2296 healthy term-born infants until 3 months of age, if parents choose to start formula feeding. Ten study centres in Spain and Poland are participating. Randomised infants receive investigational infant and follow-on formulas either based on whole goat milk or on cow milk until the age of 12 months. The goat milk formula has a whey:casein ratio of 20:80 and about 50% of the lipids are milk fat from whole goat milk, whereas the cow milk formula, used as control, has a whey:casein ratio of 60:40 and 100% of the lipids are from vegetable oils. The energy and nutrient levels in both goat and cow milk formulas are the same. The primary endpoint is the cumulative incidence of AD until the age of 12 months diagnosed by study personnel based on the UK Working Party Diagnostic Criteria. The secondary endpoints include reported AD diagnosis, measures of AD, blood and stool markers, child growth, sleep, nutrition and quality of life. Participating children are followed until the age of 5 years.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the ethical committees of all participating institutions.

TRIAL REGISTRATION NUMBER

NCT04599946.

Effects of Histamine and the α-Tocopherol Metabolite α-13'-COOH in an Atopic Dermatitis Full-Thickness Skin Model

Atopic dermatitis is a T-cell mediated inflammatory skin disease with detected elevated levels of histamine in skin or plasma. In this study, the effects of histamine in a T_H2 cytokine environment on human keratinocytes and three-dimensional skin models were investigated. These models were used to explore the anti-inflammatory properties of the α-tocopherol-derived long-chain metabolite α-13'-carboxychromanol (α-13'-COOH). Histamine and T_H2 cytokine-induced proliferation of keratinocytes was studied using a scratch assay. The inflammatory marker interleukin-8 was significantly increased in healthy and T_H2 cytokine-stimulated keratinocytes and skin models after histamine treatment. The incubation of full-thickness skin models with T_H2 cytokines and histamine resulted in morphological changes in the epidermal layer, interpreted as hyperkeratosis. α-13'-COOH significantly decreased interleukin-8 in these disease-associated skin models. Histological staining of filaggrin showed skin-strengthening effects following α-13'-COOH treatment, without changes in mRNA expression. Cytokeratin 10 mRNA expression tended to be increased in response to α-13'-COOH. Anti-allergic properties of α-13'-COOH were studied by pre-incubation of human leukocytes with α-13'-COOH. This resulted in reduced sulfido-leukotriene synthesis. The hyperproliferation effect of histamine in atopic dermatitis skin models may be of further interest to the study of disease-associated morphological changes. Moreover, α-13'-COOH is a promising natural compound for the treatment of inflammatory skin diseases.

Atopic dermatitis

Atopic dermatitis is a common inflammatory skin disorder characterised by recurrent eczematous lesions and intense itch. The disorder affects people of all ages and ethnicities, has a substantial psychosocial impact on patients and relatives, and is the leading cause of the global burden from skin disease. Atopic dermatitis is associated with increased risk of multiple comorbidities, including food allergy, asthma, allergic rhinitis, and mental health disorders. The pathophysiology is complex and involves a strong genetic predisposition, epidermal dysfunction, and T-cell driven inflammation. Although type-2 mechanisms are dominant, there is increasing evidence that the disorder involves multiple immune pathways. Currently, there is no cure, but increasing numbers of innovative and targeted therapies hold promise for achieving disease control, including in patients with recalcitrant disease. We summarise and discuss advances in our understanding of the disease and their implications for prevention, management, and future research.

Assessment of the Effectiveness of Vitamin Supplement in Treating Eczema: A Systematic Review and Meta-Analysis

Background

The morbidity of eczema has increased in the recent years, and the methods to prevent or ameliorate its effects are becoming more important. To this end, this research was conducted to determine the effectiveness of vitamin supplements in eczema therapy.

Method

Embase, PubMed, and Cochrane Central Register of Clinical Trials were searched. Only randomized controlled trials were included, and we included all quantified eligible data where the SCORing Atopic Dermatitis (SCORAD) Index or Eczema Area and Severity Index (EASI) scores were applied to assess the severity of eczema.

Results

Ten studies fulfilled the inclusion criteria, and eight of them were included for quantitative analysis (total: 456 patients). Compared to the controls, the SCORAD index or EASI decreased in the vitamin supplement group (mean difference -5.96, 95% CI: -7.69 to -4.23 for vitamin D3; mean difference -5.72, 95% CI: -11.41 to -0.03 for vitamin E; and mean difference -3.19, 95% CI: -4.27 to -2.10 for vitamin B12).

Conclusion

This study suggests that vitamin supplements could be important therapeutics to help manage eczema patients.

Approach to the Assessment and Management of Pediatric Patients With Atopic Dermatitis: A Consensus Document. Section III: Treatment Options for Pediatric Atopic Dermatitis

Because atopic dermatitis (AD) is a chronic, relapsing disease, treatment requires the use of both active therapy to control flares and preventative maintenance therapy to promote integrity of the skin barrier. In this third of four sections, important clinical considerations for the treatment of pediatric AD are reviewed. Emerging therapies in development for pediatric AD are introduced.