Development of autoimmune hair loss disease alopecia areata is associated with cardiac dysfunction in C3H/HeJ mice

Is the severity of alopecia areata associated with arterial stiffness?

Background

This study aimed to evaluate the severity of alopecia areata (AA) associations with metabolic syndrome, body composition evaluated by bioimpedance techniques, and arterial stiffness based on pulse-wave velocity analysis.

Materials and Methods

This cross-sectional study was conducted on patients referred to AA Clinic at Razi Hospital in 2021 and 2022. Patients with AA with the Severity of Alopecia Tool (SALT) score above 20% and receiving no systemic therapy were included. Patient demographic and clinical information, symptoms of metabolic syndrome, and bioimpedance factors were collected, and the relationship between disease severity, metabolic syndrome, and bioimpedance indicators was evaluated.

Results

In this study, 59 patients were examined, with 26 (44.07%) being female and 33 (55.93%) being male. The mean age of the patients was 37.42 years (standard deviation [SD] =11.28). The severity of the disease was assessed using the SALT score, with the mean severity in terms of the percentage being 69.83% (SD = 28.57%). In the regression model, SALT score was independently related to the severity of vascular stiffness after adjusting for the effect of other variables (beta = 0.033, 95% CI = 0.009-0.057, P = 0.046). Moreover, SALT score was significantly related to metabolic syndrome after adjusting for the effect of other variables (OR = 1.035, 95% CI = 1.012-1.059, P = 0.002).

Conclusion

This study found that AA severity is associated with a higher chance of having metabolic syndrome and arterial stiffness which may lead to cardiovascular diseases in patients with AA, and screening patients regarding cardiometabolic diseases is mandated.

Microglia shield the murine brain from damage mediated by the cytokines IL-6 and IFN-α

Sustained production of elevated levels of the cytokines interleukin (IL)-6 or interferon (IFN)-α in the central nervous system (CNS) is detrimental and directly contributes to the pathogenesis of neurological diseases such as neuromyelitis optica spectrum disorders or cerebral interferonopathies, respectively. Using transgenic mice with CNS-targeted production of IL-6 (GFAP-IL6) or IFN-α (GFAP-IFN), we have recently demonstrated that microglia are prominent target and effector cells and mount stimulus-specific responses to these cytokines. In order to further clarify the phenotype and function of these cells, we treated GFAP-IL6 and GFAP-IFN mice with the CSF1R inhibitor PLX5622 to deplete microglia. We examined their ability to recover from acute microglia depletion, as well as the impact of chronic microglia depletion on the progression of disease. Following acute depletion in the brains of GFAP-IL6 mice, microglia repopulation was enhanced, while in GFAP-IFN mice, microglia did not repopulate the brain. Furthermore, chronic CSF1R inhibition was detrimental to the brain of GFAP-IL6 and GFAP-IFN mice and gave rise to severe CNS calcification which strongly correlated with the absence of microglia. In addition, PLX5622-treated GFAP-IFN mice had markedly reduced survival. Our findings provide evidence for novel microglia functions to protect against IFN-α-mediated neurotoxicity and neuronal dysregulation, as well as restrain calcification as a result of both IL-6- and IFN-α-induced neuroinflammation. Taken together, we demonstrate that CSF1R inhibition may be an undesirable target for therapeutic treatment of neuroinflammatory diseases that are driven by elevated IL-6 and IFN-α production.

Current controversies in trichology: a European expert consensus statement

INTRODUCTION

Hair disorders are one of the most common conditions within dermatology practice but, although new diagnostic tools and therapeutic options have arisen, the management of these patients still represents a major clinical challenge.

OBJECTIVE

This study aimed at gathering information and achieving consensus on relevant recommendations on the latest advances in alopecia, trichoscopy and hair dermocosmetics.

METHODS

Experts of the steering committee consulted the available evidence on trichology-related areas from the past 5 years and formulated recommendations based on the evidence and their experience. A modified two-round Delphi procedure was performed among 45 European dermatologists experts in trichology to consult their degree of agreement on twenty recommendations, using a 4-point Likert scale. Consensus was defined as >80% of participants scoring either 1 (totally agree) or 2 (agree).

RESULTS

In the first round of the Delphi questionnaire, 75% of the recommendations reached consensus. Those that were not agreed upon were reformulated by the steering committee and voted again after an online meeting, where consensus was achieved in all recommendations.

CONCLUSIONS

All recommendations reached consensus after the two-round Delphi questionnaire and may be useful in clinical practice for dermatologists. The participants agreed that besides this consensus, further clinical studies are needed to assess the benefits of the emerging tools and treatments and to clarify the controversies that still exist in the field, aiming at improving patients' quality of life.

Genomic Regions Associated with the Position and Number of Hair Whorls in Horses

Simple Summary

Whorls have been used to indicate the temperaments of domestic animals; however, little is known about the biological events that drive this association. The present study is the first that aims to find the main genomic regions that influence the whorl traits in livestock, with horses as a model. Genes related to hair follicle growth were found. Interestingly, some of these genes also influence psychiatric diseases and neurological disorders, thus evidencing a consistent biological explanation for the association.

Abstract

The position and number of hair whorls have been associated with the behavior, temperament, and laterality of horses. The easy observation of whorls assists in the prediction of reactivity, and thus permits the development of better measures of handling, training, mounting, and riding horses. However, little is known about the genetics involved in the formation of hair whorls. Therefore, the aim of this study was to perform a genome-wide association analysis to identify chromosome regions and candidate genes associated with hair whorl traits. Data from 342 Quarter Horses genotyped for approximately 53,000 SNPs were used in an association study using a single-step procedure. The following traits were analyzed: vertical position of hair whorl on the head, number of whorls on the head, and number of whorls on the left and right sides of the neck. The traits had between one and three genomic windows associated. Each of them explained at least 4% of the additive variance. The windows accounted for 20–80% of additive variance for each trait analyzed. Many of the prospected genes are related to hair follicle growth. Some of these genes exert a pleiotropic effect on neurological and behavioral traits. This is the first indication of biological and physiological activity that might explain the association of hair whorls and temperament.

An integrated scalp and blood biomarker approach suggests the systemic nature of alopecia areata

BACKGROUND

Alopecia areata (AA) is characterized by immune dysregulation in both scalp and blood, but a large-scale approach establishing biomarkers of AA incorporating both scalp tissue and serum compartments is lacking. We aimed to characterize the transcriptomic signature of AA lesional and nonlesional scalp compared to healthy scalp and determine its relationship with the blood proteome in the same individuals, with comparative correlations to clinical AA disease severity.

METHODS

We evaluated lesional and nonlesional scalp tissues and serum from patients with moderate-to-severe AA (n = 18) and healthy individuals (n = 8). We assessed 33,118 genes in AA scalp tissue using RNAseq transcriptomic evaluation and 340 inflammatory proteins in serum using OLINK high-throughput proteomics. Univariate and multivariate approaches were used to correlate disease biomarkers with Severity of Alopecia Tool (SALT).

RESULTS

A total of 608 inflammatory genes were differentially expressed in lesional AA scalp (fold change/FCH>1.5, false discovery rate/FDR<0.05) including Th1 (IFNG/IL12B/CXCL11), Th2 (IL13/CCL18), and T-cell activation-related (ICOS) products. Th1/Th2-related markers were significantly correlated with AA clinical severity in lesional/nonlesional tissue, while keratins (KRT35/KRT83/KRT81) were significantly downregulated in lesional compared to healthy scalp (p < .05). Expression of cardiovascular/atherosclerosis-related markers (MMP9/CCL2/IL1RL1/IL33R/ST2/AGER) in lesional scalp correlated with their corresponding serum expression (p < .05). AA scalp demonstrated significantly greater biomarker dysregulation compared to blood. An integrated multivariate approach combining scalp and serum biomarkers improved correlations with disease severity/SALT.

CONCLUSION

This study contributes a unique understanding of the phenotype of moderate-to-severe AA with an integrated scalp and serum biomarker model suggesting the systemic nature of the disease, advocating for the need for immune-based systemic treatment.

Electrocardiogram Findings in Patients with Alopecia Areata

Introduction

While autoimmune comorbidities are common in alopecia areata, little is known about comorbid cardiovascular disease. The purpose of this study was to evaluate the incidence of bradyarrhythmia in patients with alopecia areata.

Methods

Retrospective review of electrocardiograms of 124 patients with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 50% scalp hair loss (severe alopecia areata) was conducted and compared to National Health and Nutrition Examination Survey (NHANES) data.

Results

The prevalence of bradycardia in females with alopecia areata was 24.3% (95% CI, 14.5–34.1%) and in those age 40 years or older was 40.8% (95% CI, 22.2–53.5%) compared to 19.5% in the NHANES III population. The prevalence of bradycardia in males with alopecia areata was 36.0% (95% CI, 22.7–49.3%) and in those age 40 years or older was 50.0% (95% CI, 21.7–78.3%) compared to 26.9% in the NHANES III population.

Conclusion

The potential association between bradycardia and alopecia areata merits further investigation.

Alopecia areata is not a risk factor for heart diseases: A 10-year retrospective cohort study

Alopecia areata (AA) is an autoimmune skin disease caused by chronic inflammation of hair follicles. Chronic inflammatory skin diseases such as psoriasis and lupus erythematosus can increase the risk of cardiovascular diseases. However, the relationship between AA and heart diseases (HDs) remains unclear. Therefore, we conducted this retrospective cohort study to evaluate the risk of subsequent HDs in patients with AA. We reviewed 3770 cases of AA and from 18,850 age, sex, and income level-matched controls from the National Health Insurance Service-National Sample Cohort. In the subgroup analysis, patients who suffered from alopecia totalis, alopecia universalis, and ophiasis were designated as patients with severe AA and patients having the disease for over a year were designated as patients with long-standing AA. As a result, we found that AA was not associated with a higher risk of heart failure, angina pectoris, or myocardial infarction. There was no significant increase in the risk of overall HD associated with AA (adjusted hazard ratio: 1.17; 95% confidence interval: 0.93-1.48; p = 0.177). Neither the severity nor the duration of AA was related to an increased risk of HDs. During the study period, AA patients did not show a significantly higher cumulative incidence of HDs than controls (log-rank p = 0.157). In conclusion, AA does not increase the risk of HD.

Current insight into the functions of microRNAs in common human hair loss disorders: a mini review

Alopecia areata (AA) and Androgenic alopecia (AGA) are the most common multifactorial hair loss disorders that have a serious psychological impact on the affected individuals, while frontal fibrosing alopecia (FFA) is comparatively less common. However, due to the unknown etiology and the effect of many adverse factors, the prognosis of these conditions is challenging to predict. Moreover, no approved therapy has been available to date to prevent or treat these disorders. MicroRNAs (miRNAs) are a group of evolutionary conserved small non-coding RNA molecules with significant roles in the posttranscriptional gene regulation either through mRNA degradation or translational repression. A number of biological processes are controlled by these molecules, including cell growth and differentiation, proliferation, inflammation, immune responses, and apoptosis. Recently, a handful of studies have demonstrated the impact of miRNAs on common hair loss-related disorders; however, the exhaustive molecular mechanisms are still unclear. In this review, we discussed the functional implications of miRNAs in common hair loss-related disorders and addressed their efficacy to be used for theranostic purposes shortly.

Integrated multi-omics analysis of genomics, epigenomics, and transcriptomics in ovarian carcinoma

In this study, we identified prognostic biomarkers in ovarian carcinoma by integrating multi-omics DNA copy number variation (CNV) and methylation variation (MET) data. CNV, MET, and messenger RNA (mRNA) expression were examined in 351 ovarian carcinoma patients. Genes for which expression was correlated with DNA copy-number or DNA methylation were identified; three ovarian carcinoma gene subtypes were defined based on these correlations. Overall survival and B cell scores were lower, while the macrophage cell score was higher, in the DNA imprinting centre 1 (iC1) subtype than in the iC2 and iC3 subtypes. Comparison of CNV, MET, and mRNA expression among the subtypes identified two genes, ubiquitin B (UBB) and interleukin 18 binding protein (IL18BP), that were associated with prognosis. Mutation spectrum results based on subtype indicated that UBB and IL18BP expression may be influenced by mutation loci. Mutation levels were higher in iC1 samples than in iC2 or iC3 samples, indicating that the iC1 subtype is associated with disease progression. This integrated multi-omics analysis of genomics, epigenomics, and transcriptomics provides new insight into the molecular mechanisms of ovarian carcinoma and may help identify biomolecular markers for early disease diagnosis.

Proteomic analysis reveals distinctive protein profiles involved in CD8+ T cell-mediated murine autoimmune cholangitis

Autoimmune cholangitis arises from abnormal innate and adaptive immune responses in the liver, and T cells are critical drivers in this process. However, little is known about the regulation of their functional behavior during disease development. We previously reported that mice with T cell-restricted expression of a dominant negative form of transforming growth factor beta receptor type II (dnTGFβRII) spontaneously develop an autoimmune cholangitis that resembles human primary biliary cholangitis (PBC). Adoptive transfer of CD8⁺ but not CD4⁺ T cells into Rag1^-/- mice reproduced the disease, demonstrating a critical role for CD8⁺ T cells in PBC pathogenesis. Herein, we used SOMAscan technology to perform proteomic analysis of serum samples from dnTGFβRII and B6 control mice at different ages. In addition, we analyzed CD8 protein profiles after adoptive transfer of splenic CD8⁺ cells into Rag1^-/- recipients. The use of the unique SOMAscan aptamer technology revealed critical and distinct profiles of CD8 cells, which are key to biliary mediation. In total, 254 proteins were significantly increased while 216 proteins were significantly decreased in recipient hepatic CD8⁺ cells compared to donor splenic CD8⁺ cells. In contrast to donor splenic CD8⁺ cells, recipient hepatic CD8⁺ cells expressed distinct profiles for proteins involved in chemokine signaling, focal adhesion, T cell receptor and natural killer cell-mediated cytotoxicity pathways.

Genetic analysis of interleukin 18 gene polymorphisms in alopecia areata

BACKGROUND

Alopecia areata (AA), which appears as nonscarring hair shedding on any hair-bearing area, is a common organ-specific autoimmune condition. Cytokines have important roles in the development of AA. Interleukin (IL) 18 is a significant proinflammatory cytokine that was found higher in the patients with AA. We aimed to investigate whether the IL-18 (rs187238 and rs1946518) single nucleotide polymorphisms (SNPs) may be associated with AA and/or clinical outcome of patients with AA in Turkish population.

METHODS

Genotyping of rs187238 and rs1946518 SNPs were detected using sequence-specific primer-polymerase chain reaction (SSP-PCR) method in 200 patients with AA and 200 control subjects.

RESULTS

The genotype distribution of rs1946518 (-607C>A) SNP was found to be statistically significantly different among patients with AA and controls (P = .0008). Distribution of CC+CA genotypes and frequency of -607/allele C of rs1946518 SNP were higher in patients with AA (P = .001, P = .001, respectively). The genotype distribution of rs187238 (-137G>C) SNP was found to be statistically significantly different among patients with AA and control subjects (P = .0014). Distribution of GG genotype and frequency of -137/allele G of rs187238 SNP were higher in patients with AA (P = .0003, P = .001, respectively).

CONCLUSION

The rs1946518 (-607C>A) and rs187238 (-137G>C) polymorphisms were found associated with alopecia areata disease. The study suggests that IL-18 rs187238 and rs1946518 SNPs may be the cause of the AA susceptibility.

Alopecia areata: What's new in epidemiology, pathogenesis, diagnosis, and therapeutic options?

Alopecia areata (AA) is a common and stressful disorder that results in hair loss, and resistant to treatment in some cases. Experimental and clinical evidence suggests that AA is caused by autoimmune attack against the hair follicles. The precise pathomechanism, however, remains unknown. Here, we focus on the recent progress in multidisciplinary approaches to the epidemiology, pathogenesis, and new treatments of AA in 996 publications from January 2010 to July 2016, and provide an overview of the current understanding in clinical management and research directions.

Abnormal interactions between perifollicular mast cells and CD8+ T-cells may contribute to the pathogenesis of alopecia areata

Alopecia areata (AA) is a CD8+ T-cell dependent autoimmune disease of the hair follicle (HF) in which the collapse of HF immune privilege (IP) plays a key role. Mast cells (MCs) are crucial immunomodulatory cells implicated in the regulation of T cell-dependent immunity, IP, and hair growth. Therefore, we explored the role of MCs in AA pathogenesis, focusing on MC interactions with CD8+ T-cells in vivo, in both human and mouse skin with AA lesions. Quantitative (immuno-)histomorphometry revealed that the number, degranulation and proliferation of perifollicular MCs are significantly increased in human AA lesions compared to healthy or non-lesional control skin, most prominently in subacute AA. In AA patients, perifollicular MCs showed decreased TGFβ1 and IL-10 but increased tryptase immunoreactivity, suggesting that MCs switch from an immuno-inhibitory to a pro-inflammatory phenotype. This concept was supported by a decreased number of IL-10+ and PD-L1+ MCs, while OX40L+, CD30L+, 4–1BBL+ or ICAM-1+ MCs were increased in AA. Lesional AA-HFs also displayed significantly more peri- and intrafollicular- CD8+ T-cells as well as more physical MC/CD8+ T-cell contacts than healthy or non-lesional human control skin. During the interaction with CD8+ T-cells, AA MCs prominently expressed MHC class I and OX40L, and sometimes 4–1BBL or ICAM-1, suggesting that MC may present autoantigens to CD8+ T-cells and/or co-stimulatory signals. Abnormal MC numbers, activities, and interactions with CD8+ T-cells were also seen in the grafted C3H/HeJ mouse model of AA and in a new humanized mouse model for AA. These phenomenological in vivo data suggest the novel AA pathobiology concept that perifollicular MCs are skewed towards pro-inflammatory activities that facilitate cross-talk with CD8+ T-cells in this disease, thus contributing to triggering HF-IP collapse in AA. If confirmed, MCs and their CD8+ T-cell interactions could become a promising new therapeutic target in the future management of AA.

Methylenetetrahydrofolate reductase C677T mutation in patients with alopecia areata in Turkish population

OBJECTIVE

Methylene-tetrahydrofolate reductase (MTHFR) is a key enzyme regulating folate metabolism and it is thought to influence DNA methylation and nucleic acid synthesis. Mutations in the MTHFR gene have been associated with several autoimmune disorders in previous studies. Alopecia areata (AA) is considered to be a tissue-specific autoimmune disease as the hair follicle has been targeted and antibodies to their own hair follicle structures have been developed. Since there is a common shared pathway between AA and other autoimmune disorders, we aimed to investigate a possible association between the MTHFR gene C677T mutation and AA susceptibility in the Turkish population.

METHODS

The study included 136 patients affected by AA and 130 healthy controls. Genomic DNA was isolated and genotyped using a polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) assay for the MTHFR gene C677T mutation.

RESULTS

The distributions of genotype and allele frequencies of MTHFR gene C677T mutation were statistically different between AA patients and the control group (p=0.036 and p=0.011, respectively). High differences were also observed when the patients and controls were compared according to CC versus CT+TT (p=0.012). CT+TT genotypes and T allele of MTHFR gene C677T mutation were found to be a susceptibility factor for AA in the Turkish population.

CONCLUSION

The results suggest that MTHFR gene C677T mutation may have an effect on the risk of alopecia areata in the Turkish population. This is the first study reporting the association between the MTHFR (C677T) genotype and AA.