Refractory alopecia areata with single hairs imitating frontal fibrosing alopecia: a prospective observational study

BACKGROUND

Lonely hair sign is considered as a clue to the diagnosis of frontal fibrosing alopecia (FFA).

OBJECTIVE

To report an undescribed variant of alopecia areata (AA) with which the patient developed single hairs and other features similar to FFA and to determine the underlying mechanism.

METHODS

We conducted a prospective observational study in patients who presented with receding hairline and single hairs, evaluating the clinical, trichoscopic, and histological features and their correlation. Immunochemistry studies were performed to describe the microenvironment.

RESULTS

Eighteen patients were enrolled in the study. Despite the similarity to FFA clinically, these patients showed different histopathology which revealed a normal number of pilosebaceous units, one anagen hair in one or more pilosebaceous units, and others in telogen stage, consistent with single hairs under the naked eye or under trichoscopy. The severity of the hair loss assessed by SALT was no more than 50, but the response to conventional therapy was poor.

CONCLUSIONS

This study reports a unique variant of AA. The pathological basis is an increase in the telogen hair follicles, with one anagen hair in one or more pilosebaceous units. Minimal inflammation consisting of CD3+ T lymphocytes and mast cells was demonstrated in the microenvironment.

Divergent progression pathways in male androgenetic alopecia and female pattern hair loss: Trichoscopic perspectives

BACKGROUND

Despite similarities in progressive miniaturization of hair follicles and transition of terminal hairs to vellus hairs, insufficient trichoscopic comparisons between male androgenetic alopecia (MAGA) and female pattern hair loss (FPHL) hinder our ability to select effective treatments.

AIM

Our study aimed to explore gender-specific trichoscopic characteristics of MAGA and FPHL, while formulating hypotheses regarding the progression of these conditions across clinical stages.

METHODS

We classified 126 male MAGA subjects using Hamilton-Norwood Classification and 57 FPHL subjects using adopted Sinclair Scale. Subsequently, we analyzed nine trichoscopic factors divided into three categories: hair-diameter related, hair-number per follicular unit related, and hair density related factors.

RESULTS

Of the nine quantitative trichoscopic factors, hair-diameter and hair-number per follicular unit showed strong correlations with clinical stages in both genders. Hair density, a common trichoscopic factor for hair loss evaluation, weakly correlated with clinical stages in FPHL, but not at all in MAGA. In addition, MAGA was characterized by a progressive reduction in hair-diameter, followed by a reduction in hair-number per follicular unit. FPHL, on the contrary, showed the opposite progression.

CONCLUSIONS

Trichoscopic factors vary with disease severity in a gender-specific manner. Our research highlights that MAGA and FPHL involve two distinct streams: hair-diameter decreasing by hair follicle miniaturization (Stream 1), and hair-number per follicular unit decreasing by hair follicle tri-lineage niche dysfunction (Stream 2). MAGA typically starts from Stream 1 to Stream 2, while FPHL starts from Stream 2. These diverse progression pathways underscore the importance of personalized treatment approaches.

ANTXR1 deficiency promotes fibroblast senescence: implications for GAPO syndrome as a progeroid disorder

ANTXR1 is one of two cell surface receptors mediating the uptake of the anthrax toxin into cells. Despite substantial research on its role in anthrax poisoning and a proposed function as a collagen receptor, ANTXR1's physiological functions remain largely undefined. Pathogenic variants in ANTXR1 lead to the rare GAPO syndrome, named for its four primary features: Growth retardation, Alopecia, Pseudoanodontia, and Optic atrophy. The disease is also associated with a complex range of other phenotypes impacting the cardiovascular, skeletal, pulmonary and nervous systems. Aberrant accumulation of extracellular matrix components and fibrosis are considered to be crucial components in the pathogenesis of GAPO syndrome, contributing to the shortened life expectancy of affected individuals. Nonetheless, the specific mechanisms connecting ANTXR1 deficiency to the clinical manifestations of GAPO syndrome are largely unexplored. In this study, we present evidence that ANTXR1 deficiency initiates a senescent phenotype in human fibroblasts, correlating with defects in nuclear architecture and actin dynamics. We provide novel insights into ANTXR1's physiological functions and propose GAPO syndrome to be reconsidered as a progeroid disorder highlighting an unexpected role for an integrin-like extracellular matrix receptor in human aging.

Dermoscopic findings and comparison of usefulness of longitudinal versus transversal sections in the histological diagnosis of alopecia X

BACKGROUND

A combination of dermoscopic and histological findings may provide useful information for the diagnosis of hair follicle diseases. However, there are no studies on dermoscopic-histopathological correlations in dogs affected by alopecia X, and comparison of longitudinal versus transversal sectioning of skin biopsy specimens in the assessment of this hair loss disorder has not been thoroughly investigated.

HYPOTHESIS/OBJECTIVES

The aim of this study was to correlate dermoscopic and histological features using both longitudinal and transversal sectioning of skin biopsy samples to gain additional information for the diagnosis of alopecia X.

ANIMALS

Nineteen Pomeranian dogs affected by alopecia X and five healthy Pomeranians as controls.

MATERIALS AND METHODS

Dermoscopic-histological correlation was performed within the diseased group, whereas histological comparisons against controls. The demographic and clinical characteristics also were related to the histological findings.

RESULTS

The dermoscopic findings revealed scattered, thinned, short hairs mixed with amorphous keratoseborrhoeic-like material (follicular plugging), perifollicular and intrafollicular scaling, and hyperpigmentation varying from pinpoint black spots to a diffuse texture. Dermoscopic findings correlated with histological findings for selected qualitative and quantitative findings. The usefulness of transversal sections was demonstrated in accurately determining the hair follicular density and counts, growth arrest phases and in identifying mineralisation of hair follicle basement membrane when compared to the longitudinal. Conversely, no correlations between histological findings and demographic and clinical characteristics were detected.

CONCLUSIONS AND CLINICAL RELEVANCE

These data provide evidence of the usefulness of dermoscopic evaluation as an accessory diagnostic tool and of transversal sections of skin biopsies as complementary to the diagnosis of alopecia X.

Clinical Characterization and Treatment Response of Folliculitis Decalvans Lichen Planopilaris Phenotypic Spectrum: A Unicentre Retrospective Series of 31 Patients

Folliculitis decalvans and lichen planopilaris phenotypic spectrum has been described as a form of cicatricial alopecia. The aim of this study is to describe the clinical and trichoscopic features and therapeutic management of this condition in a series of patients. A retrospective observational unicentre study was designed including patients with folliculitis decalvans and lichen planopilaris phenotypic spectrum confirmed with biopsy. A total of 31 patients (20 females) were included. The most common presentation was an isolated plaque of alopecia (61.3%) in the vertex. Trichoscopy revealed hair tufting with perifollicular white scaling in all cases. The duration of the condition was the only factor associated with large plaques (grade III) of alopecia (p = 0.026). The mean time to transition from the classic presentation of folliculitis decalvans to folliculitis decalvans and lichen planopilaris phenotypic spectrum was 5.2 years. The most frequently used treatments were topical steroids (80.6%), intralesional steroids (64.5%) and topical antibiotics (32.3%). Nine clinical relapses were detected after a mean time of 18 months (range 12-23 months). Folliculitis decalvans and lichen planopilaris phenotypic spectrum is an infrequent, but probably underdiagnosed, cicatricial alopecia. Treatment with anti-inflammatory drugs used for lichen planopilaris may be an adequate approach.

Clinicopathologic and trichoscopic features of keratosis follicularis spinulosa decalvans: A case series study

Keratosis follicularis spinulosa decalvans (KFSD) is a rare X-linked hereditary disorder characterized by the triad of follicular hyperkeratosis-photophobia-alopecia. The clinical heterogeneity makes the diagnosis difficult. To investigate the clinicopathologic and trichoscopic features of KFSD and to further clarify the essential requisites for the diagnosis, we conducted a retrospective study of patients with KFSD. The clinical information, histologic features, and trichoscopic findings were evaluated. Eight patients were from seven separate families. Two females were mother and daughter from the same family and the other six patients were male and represented sporadic cases. The average age of onset of alopecia was 21.25 years. Involvement of the scalp hairs leading to progressive scarring alopecia on the midline of the scalp with variable degrees of inflammation was the pathognomonic feature. It typically began after puberty. Vellus hair-associated follicular hyperkeratosis affected all of the patients. However, photophobia was not a constant feature. Histopathologic examination revealed disorders of the hair follicle with an acute-chronic inflammatory response. Follicular changes including fused infundibulum, the protrusion of the outer root sheath into the follicular canal, and a dilatation of the follicles at the isthmus level caused by the occlusion of keratin were observed. The trichoscopic features included perifollicular scaling, tufted hairs, and loss of follicular openings. In conclusion, terminal hair involvement, either scalp hairs, eyebrows, or eyelashes, and the hyperkeratosis of the follicle of vellus hairs is the diagnostic basis of KFSD. We hypothesize that follicular changes in histopathology are the primary event that trigger variable inflammation and further follicular destruction.

Transcriptome analysis of frontal fibrosis alopecia revealed involvement of immune cells and ferroptosis

BACKGROUND

Frontal fibrosis alopecia (FFA) is a primary cicatricial alopecia and has received increasing attention in recent years. However, the pathogenesis of FFA has not been fully elucidated.

METHODS AND RESULTS

Herein, we collected the transcriptome data of scalp lesions of seven patients with FFA and seven healthy controls. The differential expression analysis and weighted gene co-expression network analysis were conducted and we identified 458 differentially expressed genes (DEGs) in two key modules. Later, we performed functional enrichment analysis and functional modules identification, revealing the participation of immune response and fatty acid metabolism. Based on the results, we processed further studies. On the one hand, we analyzed the infiltrating immune cells of FFA through CIBERSORT algorithm, indicating the activation of M1 macrophage and CD8+ T cell. On the other hand, considering lipid metabolism of FFA and oxidative stress of hair follicle cells in alopecia, we explored the potential ferroptosis of FFA. By intersection of DEGs and ferroptosis-related genes from FerrDb database, 19 genes were identified and their expression was validated in an external dataset containing 36 FFA cases and 12 controls. Then, we used LASSO algorithms to construct a four-gene diagnostic model, which achieved an AUC of 0.924 in validation dataset. Additionally, the immune cells were found to be related to ferroptosis in FFA.

CONCLUSION

Taken together, this study contributed to reveal the molecular mechanisms of FFA and is expected to inspire future research on treatment.

The modified HoVert (mHoVert) method improves diagnostic certainty compared to the St John's protocol for alopecia biopsy specimens: A retrospective single center study

BACKGROUND

Access to vertical and transverse sections of a punch biopsy specimen improves the diagnosis of alopecia. Both two biopsy specimen and single-punch biopsy specimen techniques to visualize both transverse and vertical sections have been described. Their comparative diagnostic certainty is not known. We aimed to assess the diagnostic certainty of a modified HoVert (mHoVert) method, without direct immunofluorescence (DIF), compared to the St John's protocol, a two-biopsy technique with DIF.

METHODS

Fifty-seven cases of alopecia processed using the St John's protocol and 60 cases of alopecia processed using mHoVert were reviewed. Diagnoses made were rated as certain/probable, possible, or uncertain, depending on the language in the histopathology report. Cases processed by the St John's protocol had final diagnosis and DIF result recorded.

RESULTS

In the mHoVert group, significantly more diagnoses were certain/probable (66%, 95% confidence interval [CI]: 57%-75%), compared to 46% (95% CI: 36%-56%) of diagnoses in the St John's protocol group (p = 0.005). DIF result did not affect the final diagnosis in any of the 57 cases reviewed.

CONCLUSIONS

DIF is not required in the diagnosis of most cases of alopecia. The mHoVert method provides more certain/probable diagnoses than the St John's protocol and can reduce cost and patient morbidity.

A missense mutation in Lama3 causes androgen alopecia

Hair loss disorders such as androgenetic alopecia have caused serious disturbances to normal human life. Animal models play an important role in exploring pathogenesis of disease and evaluating new therapies. NIH hairless mice are a spontaneous hairless mouse discovered and bred in our laboratory. In this study, we resequenced the genomes of NIH normal mice and NIH hairless mice and obtained 3,575,560 high-quality, plausible SNP loci and 995,475 InDels. The Euclidean distance algorithm was used to assess the association of SNP loci with the hairless phenotype, at a threshold of 0.62. Two regions of chromosome 18 having the highest association with the phenotype contained 345 genes with a total length of 13.98 Mb. The same algorithm was used to assess the association of InDels with the hairless phenotype at a threshold of 0.54 and revealed a region of 25.45 Mb in length, containing 518 genes. The mutation candidate gene Lama3 (NM_010680.2: c.652C>T; NP_034810.1: p. Arg217Cys) was selected based on the results of functional gene analysis and mutation prediction screening. Lama3 (R217C) mutant mice were further constructed using CRISPR/Cas9 technology, and the relationship between Lama3 point mutations and the hairless phenotype were clarified by phenotypic observation. The results showed that male Lama3 point mutation mice started to lose hair on the 80th day after birth, and the hair loss area gradually expanded over time. H&E staining of skin sections showed that the point mutation mice had increased sebaceous glands in the dermis and missing hair follicle structure (i.e., typical symptoms of androgenetic alopecia). This study is a good extension of the current body of knowledge about the function of Lama3, and the constructed Lama3 (R217C) mutant mice may be a good animal model for studying androgenetic alopecia.

Widespread, symmetric, noninflammatory alopecia associated with follicular dysplasia in the American red squirrel (Tamiasciurus hudsonicus)

This report describes a unique pattern of alopecia in 8 American red squirrels (Tamiasciurus hudsonicus) from 2013 to 2021. All animals were juveniles; 6 were female and 2 were male. Seven presented between September and November, and one presented in April. All squirrels had widespread, bilaterally symmetric, noninflammatory, well-demarcated alopecia involving the entire trunk and legs and normal hair on their muzzle and dorsal surfaces of their paws. Six months later, a normal hair coat had grown on 2 of the animals, which were littermates. Hair fully grew 2 months later in another animal. Histopathology of the alopecic skin was performed in 7 of 8 animals. The following changes were noted: bent and coiled hairs, perforating folliculitis, melanin clumping, and distortion of hair shafts. Based on features of follicular dysplasia and apparent seasonality, this condition has some similarities to canine seasonal flank alopecia. A genetic etiology is suspected.

Alopecia Areata: Current Treatments and New Directions

Alopecia areata is an autoimmune hair loss disease that is non-scarring and is characterized by chronic inflammation at the hair follicle level. Clinically, patients' presentation varies from patchy, circumscribed scalp involvement to total body and scalp hair loss. Current management is guided by the degree of scalp and body involvement, with topical and intralesional steroid injections as primarily first-line for mild cases and broad immunosuppressants as the mainstay for more severe cases. Until recently, the limited number of blinded, randomized, placebo-controlled clinical trials for this disease had made establishing an evidence-based treatment paradigm challenging. However, growing insights into the pathogenesis of alopecia areata through blood and tissue analysis of human lesions have identified several promising targets for therapy. T-helper (Th) 1/interferon skewing has traditionally been described as the driver of disease; however, recent investigations suggest activation of additional immune mediators, including the Th2 pathway, interleukin (IL)-9, IL-23, and IL-32, as contributors to alopecia areata pathogenesis. The landscape of alopecia areata treatment has the potential to be transformed, as several novel targeted drugs are currently undergoing clinical trials. Given the recent US FDA approval of baricitinib and ritlecitinib, Janus kinase (JAK) inhibitors are a promising drug class for treating severe alopecia areata cases. This article will review the efficacy, safety, and tolerability of current treatments for alopecia areata, and will provide an overview of the emerging therapies that are leading the revolution in the management of this challenging disease.

Linear alopecia in pediatrics: RCM and dermoscopy reveal diagnostic cues

BACKGROUND

Alopecia areata (AA), trichotillomania (TM), nevus sebaceous (NS), and linear scleroderma en coup de sabre (LSCS) can all present with a patch of linear alopecia, making diagnosis challenging. The purpose of this study was to combine reflectance confocal microscopy (RCM) and dermoscopy in the diagnosis of these lesions in children.

METHODS

A total of 36 patients with linear alopecia were enrolled, of whom 14 had AA, seven had TM, nine had NS, and six had LSCS. We evaluated the characteristics and distinguishing features of the four conditions using RCM and dermoscopy.

RESULTS

The key to differential diagnosis was the dermal Hair follicle density in the dermis was decreased in AA, and the size and density of the follicular openings were normal in TM. In NS, the major features were petal-like and frogspawn-like structures. In LSCS, dermal papillary rings, sebaceous glands, and follicles were partially or completely missing, and abundant fibrous material was distributed in the dermis. Dermoscopy revealed alopecia, and all four conditions resulted in decreased hair density. AA patients exhibited yellow dots, black dots, and exclamation mark hairs. TM patients presented with irregularly broken hairs and blood spots. Both NS and LSCS patients exhibited an absence of follicular openings; NS patients demonstrated whitish and yellowish round structures, while an atrophic area with white patches, linear vessels, and no yellow or black dots was observed in LSCS patients CONCLUSION: RCM combined with dermoscopy can provide additional information on disease states and differentiate between AA, TM, NS, and LSCS.

Canine noninflammatory alopecia: An approach to its classification and a diagnostic aid

Noninflammatory alopecia is common in dogs and is a frequent cause to consult a veterinarian. It is also a common reason to take biopsies. Noninflammatory alopecia can be attributed to a decreased formation or cytodifferentiation of the hair follicle or the hair shaft in utero, resulting in congenital alopecia. Congenital alopecia often has a hereditary cause, and examples of such disorders are ectodermal dysplasias associated with gene variants of the ectodysplasin A gene. Noninflammatory alopecia may also be caused by impaired postnatal regeneration of hair follicles or shafts. Such disorders may have a clear breed predilection, and alopecia starts early in life. A hereditary background is suspected in those cases but has not been proven. They are referred to as follicular dysplasia although some of these disorders present histologically like a hair cycle disturbance. Late-onset alopecia is usually acquired and may be associated with endocrinopathies. Other possible causes are impaired vascular perfusion or stress. As the hair follicle has limited possible responses to altered regulation, and histopathology may change during the course of a disease, a detailed clinical history, thorough clinical examination including blood work, appropriate biopsy site selection, and detailed histological findings need to be combined to achieve a final diagnosis. This review aims to provide an overview about the known noninflammatory alopecic disorders in dogs. As the pathogenesis of most disorders is unknown, some statements are based on comparative aspects or reflect the authors' opinion.

The histopathologic diagnosis of traction alopecia: An evidence-based model

BACKGROUND

Traction alopecia (TA) is common, but histopathologic criteria for TA have not been objectively defined.

OBJECTIVE

Determine whether the pauci-follicular unit (PFU) can be used as a diagnostic criterion for TA. Compared to a normal follicular unit (NFU), the PFU is a noninflamed follicular unit with an intact sebaceous gland but fewer than 2 follicles.

METHODS

A retrospective review of 25 cases of TA and 25 cases of "normal scalp" was performed. Data included all follicles (by size and phase), sebaceous glands, and total follicular units.

RESULTS

Comparing data (traction vs normal), we found a significantly higher number of PFUs in cases of TA (median 6 vs 0, P < .001), which can be used as a helpful and easily recognizable diagnostic tool in diagnosing cases of TA.

LIMITATIONS

Comparison to other forms of alopecia was not performed.

CONCLUSIONS

The number of PFUs in an alopecia biopsy can be used to establish the diagnosis of TA.

Frontal fibrosing alopecia and personal care product use: a systematic review and meta-analysis

BACKGROUND

Frontal fibrosing alopecia (FFA) is a cicatricial alopecia affecting the frontotemporal hairline. Given that this scarring, immune-mediated follicular destruction most commonly affects postmenopausal Caucasian women, researchers have postulated that there are hormonal and genetic components; however, the etiology of FFA is still unknown. Recently, dermatologists have reported cases of FFA as being potentially caused by cosmetic products, such as sunscreen and shampoo. Therefore, this systematic review and meta-analysis intend to be the first to analyze the relationship between FFA and cosmetic/personal care products and treatments, including sunscreen, moisturizer, foundation, shampoo, conditioner, hair mousse, hair gel, hair dye, hair straightening/rebonding, chemical/laser facial resurfacing, aftershave, and facial cleanser.

METHODS

The Cochrane, PubMed, EMBASE, and Medline (Ovid) databases were searched for the relevant studies from the date of inception to August 2022. Case-control, cross-sectional, and cohort studies examining the effects of cosmetic/personal care product use on FFA, available in English full-text, were included. Analyses were performed using Review Manager, version 5.4. Results were reported as an odds ratio (OR) with a 95% confidence interval (CI); p values < 0.05 were considered significant.

RESULTS

Nine studies were included in our quantitative analyses, totaling 1,248 FFA patients and 1,459 controls. There were significant positive associations found for FFA and sunscreen (OR 3.02, 95% CI 1.67-5.47; p = 0.0003) and facial moisturizer (OR 2.20, 95% CI 1.51-3.20; p < 0.0001) use. Gender sub-analyses demonstrated a positive association for FFA and facial moisturizer in men (OR 5.07, 95% CI 1.40-18.32; p = 0.01), but not in women (OR 1.58, 95% CI 0.83-2.98; p = 0.16). Both gender sub-analyses were significantly positive for the association with facial sunscreen (Male OR 4.61, 95% CI 1.54-13.78, p = 0.006; Female OR 2.74, 95% CI 1.32-5.70, p = 0.007). There was no association found for a facial cleanser (OR 1.14, 95% CI 0.33-1.52; p = 0.51), foundation (OR 1.13, 95% CI 0.83-1.55; p = 0.21), shampoo (OR 0.49, 95% CI 0.22-1.10; p = 0.08), hair conditioner (OR 0.81, 95% CI 0.52-1.26; p = 0.35), hair mousse (OR 1.37, 95% CI 0.75-2.51; p = 0.31), and hair gel (OR 0.90, 95% CI 0.48-1.69; p = 0.74), hair dye (OR 1.07, 95% CI 0.69-1.64; p = 0.77), hair straightening/rebonding (OR 0.88, 95% CI 0.08-9.32; p = 0.92), hair perming (OR 1.41, 95% CI 0.89-2.23; p = 0.14), facial toner (OR 0.51, 95% CI 0.12-2.21; p = 0.37), or aftershave (OR 1.64, 95% CI 0.28-9.49; p = 0.58).

CONCLUSIONS

This meta-analysis strongly suggests that leave-on facial products, facial sunscreen and moisturizer, are associated with FFA. While the association with facial moisturizer did not persist when stratifying for female populations, gender sub-analyses remained significant for a facial sunscreen. There was no significant relationship found with hair products or treatments. These findings suggest a potential environmental etiology in the development of FFA, particularly UV-protecting chemicals.

Application of Autologous Hair Transplantation Technique in Children with Cicatricial Alopecia

INTRODUCTION

Cicatricial alopecia not only affects the appearance of children's heads and faces but also their mental health in the long term. This study aims to explore the therapeutic characteristics and clinical effects of autologous hair transplantation technology in children with cicatricial alopecia.

METHODS

Children in our department who received autologous hair transplantation technology for cicatricial baldness of the scalp from February 2019 to October 2022 were collected. Their basic information was analyzed, and postoperative follow-up was conducted, including calculation of hair follicle survival rate, hair growth, complications, and an efficacy satisfaction survey given to the children's family members.

RESULTS

Thirteen children were included in this study (10 males and 3 females), aged from 4 years 1 month to 12 years 10 months, with an average age of 7 years 5 months. Two hundred to 2500 hair follicular units were extracted, with an average recipient area of 22.7 cm2, an average hair follicle unit density of 55.3 ± 9.1 per cm2, and an average hair/follicular unit (hair/FU) ratio of 1.75 ± 0.07. Thirteen children in this group were followed up for 6-12 months with the following treatment options: FUE (follicular unit extraction, 9 cases), FUT (follicular unit transplantation, 3 cases), and FUT combined with FUE (1 case). The average hair survival rate was 85.3%. Except for one child with temporary folliculitis, there were no complications. The GAIS score is divided into five levels: complete improvement (2 cases), obvious improvement (10 cases), partial improvement (1 case), no improvement (0 cases), and deterioration (0 cases). The patient satisfaction results included very satisfied (2 cases), mostly satisfied (10 cases), and dissatisfied (1 case).

CONCLUSION

Autologous hair transplantation technology is a safe and effective method for children with cicatricial alopecia.

Patterns of Mucin Deposition in Lichen Planopilaris: A Journey From Follicular "Bubbles" to Perifollicular Fibroplasia

ABSTRACT

Lichen Planopiolaris (LPP) is a scarring alopecia characterised by a perifollicular lymphoid cell infiltrate at the level of the infundibulum and isthmus. While perifollicular mucinous fibroplasia is an established finding in LPP, intrafollicular mucin deposition has not been previously reported. We describe two cases with this histopathology and suggest it may represent a helpful clue to the diagnosis of LPP, in the appropriate clinical setting.

A case of scarring and nonscarring alopecia secondary to vascular occlusion with dermal filler

We report a case of scarring and nonscarring alopecia secondary to vascular occlusion with dermal filler. Vascular occlusion is a known complication of dermal filler injections, and alopecia as a clinical sequela has only rarely been reported. Our novel use of hydroxychloroquine, in addition to hyaluronidase and oral and topical steroids, may improve clinical outcomes associated with this complication.

Secondary alopecia induced by aesthetic procedures: An unrecognized potential complication

Surgical facelifts and noninvasive techniques such as mesotherapy, hyaluronic fillers and botulinum toxin, among other procedures are widely used nowadays to reverse skin ageing and achieve rejuvenation effects. Secondary alopecia due to cosmetic procedures is a rare side effect and is poorly described in the literature. The mechanisms in which hair loss develops after an aesthetical procedure or surgical technique are not well known. The development of secondary scarring alopecia or non-scarring alopecia depends upon the interaction between different external factors, the individual host response and the extent of damage to the hair follicle anatomy. Current knowledge hints at the type of substance used, pressure to hair structures and vasculature due to the materials used, previously unknown or unaware hair disorder, and poor surgical techniques to be the main factors contributing to the development of secondary alopecia. Physicians and patients must be aware of all the substances used for the procedures and be attentive to any change in hair density or hair loss. Clinicians must have a low threshold to take biopsies if the risk of scarring alopecia may occur. Herein, we review the clinical, trichoscopic, histopathological findings and potential pathophysiological mechanisms of hair loss due to different aesthetic procedures.

Excess KLHL24 Impairs Skin Wound Healing through the Degradation of Vimentin

Start codon variants in ubiquitin ligase KLHL24 lead to a gain-of-function mutant KLHL24-ΔN28, which mediates the excessive degradation of keratin 15, desmin, and keratin 14, resulting in alopecia, cardiopathy, and epidermolysis bullosa syndrome. Patients with alopecia, cardiopathy, and epidermolysis bullosa syndrome normally present atrophic scars after wounds heal, which is rare in KRT14-related epidermolysis bullosa. The mechanisms underlying the formation of atrophic scars in epidermolysis bullosa of patients with alopecia, cardiopathy, and epidermolysis bullosa syndrome remain unclear. This study showed that KLHL24-ΔN28 impaired skin wound healing by excessively degrading vimentin. Heterozygous Klhl24c.3G>T knock-in mice displayed delayed wound healing and decreased wound collagen deposition. We identified vimentin as an unreported substrate of KLHL24. KLHL24-ΔN28 mediated the excessive degradation of vimentin, which failed to maintain efficient fibroblast proliferation and activation during wound healing. Furthermore, by mediating vimentin degradation, KLHL24 can hinder myofibroblast activation, which attenuated bleomycin-induced skin fibrosis. These findings showed the function of KLHL24 in regulating tissue remodeling, atrophic scarring, and fibrosis.

Minimizing Bias in Alopecia Diagnosis in Skin of Color Patients

Alopecia is one of the most common dermatologic conditions affecting black patients, with a significantly negative impact on quality of life.1,2 Timely and accurate diagnosis is therefore critical in order to reverse or halt progression of disease.3 Unfortunately, lack of representation of skin of color (SOC) patients in the current literature may contribute to misdiagnosis as providers may be unfamiliar with the clinical spectrum of alopecia presenting in darker scalps.4 Some scarring alopecia subtypes such as Central Centrifugal Cicatricial Alopecia (CCCA) are more prevalent in certain racial groups. However, focusing solely on patient demographics and gross clinical findings may obscure accurate diagnoses. To distinguish alopecia findings in Black patients, a dedicated approach using a combination of clinical exam findings and patient history, along with trichoscopy and biopsy, is essential to prevent misdiagnosis and improve clinical and diagnostic outcomes. We present three cases of alopecia in patients of color which the initial suspected clinical diagnosis did not correspond with trichoscopic and biopsy results. We challenge clinicians to reexamine their biases and fully evaluate patients of color with alopecia. An examination should include a thorough history, clinical examination, trichoscopy, and potentially a biopsy, particularly when findings do not correlate. Our cases highlight the challenges and disparities that exist in diagnosis of alopecia in Black patients. We emphasize the need for continued research regarding alopecia in skin of color and the importance of a complete workup for alopecia to improve diagnostic outcomes.Balazic E, Axler E, Nwankwo C, et al. Minimizing bias in alopecia diagnosis in skin of color patients. J Drugs Dermatol. 2023;22(7):703-705. doi:10.36849/JDD.7117.  .

Diagnosis and differential diagnosis of tertiary androgenetic alopecia with severe alopecia areata based on high-resolution MRI

BACKGROUND AND AIM

No previous study investigated the anatomical changes of the scalp and hair follicles between tertiary androgenetic alopecia and severe alopecia areata using high-resolution magnetic resonance imaging (HR-MRI). This study aimed to explore the value of HR-MRI in assessing alopecia.

MATERIALS AND METHODS

Forty-eight people were included in this study. The imaging indicators of the vertex and occipital scalp were recorded and compared. The logistic regression model was developed for the indicators that differed between tertiary androgenetic alopecia and severe alopecia areata. The receiver-operating characteristic (ROC) curve was used to assess the diagnostic efficacy of the model for tertiary androgenetic alopecia and severe alopecia areata.

RESULTS

At the vertex, the thickness of the subcutaneous tissue layer, follicle depth, relative follicle depth, total number of follicles within a 2-cm distance, and number of strands reaching the middle and upper third of the subcutaneous fat layer within a 2-cm distance were statistically different between patients with tertiary androgenetic alopecia, those with severe alopecia areata, and healthy volunteers (p < 0.05). The logistic regression model suggested that the subcutaneous tissue layer thickness was important in discriminating tertiary androgenetic alopecia from severe alopecia areata. The ROC curve showed that the area under the curve, sensitivity, specificity, and best cutoff values of the subcutaneous tissue layer were 0.886, 94.4%, 70%, and 4.31 mm, respectively.

CONCLUSIONS

HR-MRI can observe the changes in anatomical structures of the scalp and hair follicles in patients with alopecia. HR-MRI can be applied to the differential diagnosis of tertiary androgenetic alopecia and severe alopecia areata.

Sarcoidosis Coexisting With Distinct Forms of Alopecia on the Scalp: A Case Series

ABSTRACT

Sarcoidosis is an idiopathic multisystem inflammatory disease that can affect virtually any part of the body. Often, it can initially present solely in the skin. Histologically, it is characterized by noncaseating, 'naked' granulomas in the dermis and subcutaneous tissue. Clinically, sarcoidosis is often referred to as a 'mimicker' of many other pathologic processes because of its wide array of presentations. Occasionally, sarcoidosis can present in the scalp as both a scarring and nonscarring alopecia. There are countless reports of sarcoidosis mimicking various other alopecias including acne keloidalis nuchae, discoid lupus erythematosus, frontal fibrosing alopecia, lichen planopilaris, and alopecia areata totalis. In this case series, we present 2 novel cases of sarcoidosis not just clinically mimicking other forms of alopecia but occurring in conjunction with a separate and histologically distinct primary alopecia.

Protein profiling of forehead epidermal corneocytes distinguishes frontal fibrosing from androgenetic alopecia

Protein profiling offers an effective approach to characterizing how far epidermis departs from normal in disease states. The present pilot investigation tested the hypothesis that protein expression in epidermal corneocytes is perturbed in the forehead of subjects exhibiting frontal fibrosing alopecia. To this end, samples were collected by tape stripping from subjects diagnosed with this condition and compared to those from asymptomatic control subjects and from those exhibiting androgenetic alopecia. Unlike the latter, which exhibited only 3 proteins significantly different from controls in expression level, forehead samples from frontal fibrosing alopecia subjects displayed 72 proteins significantly different from controls, nearly two-thirds having lower expression. The results demonstrate frontal fibrosing alopecia exhibits altered corneocyte protein expression in epidermis beyond the scalp, indicative of a systemic condition. They also provide a basis for quantitative measures of departure from normal by assaying forehead epidermis, useful in monitoring response to treatment while avoiding invasive biopsy.

Clinical and dermatoscopic features of temporal triangular alopecia in infants

OBJECTIVE

To summarize the clinical and dermatoscopic features of temporal triangular alopecia in infants and explore the clinical significance of dermatoscopy in the diagnosis of triangular alopecia temporalis in infants.

METHODS

A retrospective analysis was performed on 20 children with temporal triangular alopecia diagnosed in the dermatology clinic of Tianjin Children's Hospital from January 2015 to December 2021. Dermatoscopy was performed on all children, and images were collected.

RESULTS

The clinical features of 20 children were 15 males and five females, all of which were born immediately after birth; There were eight cases (40%) in the left temporal region, 10 cases (50%) in the right temporal region, one case (5%) in the head region, and one case (5%) in the occipital region; 19 cases were single (95%), one case was multiple (5%); There were 21 skin lesions, 15 triangular lesions (71.4%), four quasi-circular lesions (19%), and two lance-shaped lesions (9.5%). Trichoscopic features: The hair follicle opening in all skin lesions is normal, and the hair follicle opening can be seen with fluffy hair (vellus hair). The vellus hair is evenly distributed, and the length is diverse (both short and long vellus hair exist in the same hair loss area). There are 14 cases of white vellus hair (70%), five cases of white spots (25%), one case of honeycomb pigment pattern (5%), and one case of vascular dilation pattern (5%).

CONCLUSION

Temporal triangular alopecia in infants has typical clinical and dermatoscopic characteristics, and the dermatoscopy can provide clinical basis for its diagnosis and differential diagnosis.

IL-17 Expression in the Perifollicular Fibrosis in Biopsies From Lichen Planopilaris

BACKGROUND

Lichen planopilaris (LPP) is a primary lymphocytic cicatricial alopecia for which therapy is often ineffective and there is no cure.

OBJECTIVES

Looking for a new targetable molecule in the treatment of LPP, we sought to verify whether IL-17 expression is increased in scalp biopsies from patients with active scalp lesions of LPP.

METHODS

Horizontal sections of hematoxylin and eosin-stained slides from 40 scalp biopsies of active LPP were retrospectively collected and stained with the monoclonal antibody against IL-17 (Abcam, Cambridge, MA; ab79056, dilution 1:100). Twenty biopsies from patients with chronic telogen effluvium served as controls because of their morphological resemblance to the normal scalp. Statistical analysis was performed using IBM SPSS Statistics for Windows (IBM Corporation, Armonk, NY).

RESULTS

The main finding was the positive cytoplasmic expression of IL-17 in the perifollicular fibrosis of the affected follicles in LPP which was statistically significant compared with the controls ( P < 0.0001). The labeled cells were identified as fibroblasts based on their spindle shape and fascicular concentric arrangement in tight perifollicular distribution. Although most of the LPP specimens (n = 35; 87.5%) also revealed cytoplasmic IL-17 expression in the lichenoid inflammatory infiltrate, the results were not statistically significant ( P = 0.1351).

CONCLUSION

Our immunohistochemistry results show that blocking the IL-17 inflammatory pathway may interfere with the progression of the perifollicular fibrosis and inflammation in LPP.

Rare Concurrence of Alopecia Areata in the Setting of the Lipedematous Scalp

ABSTRACT

The lipedematous scalp (LS) is characterized by a thickened scalp because of the increased thickness of the subcutaneous fat layer. When the soft and boggy scalp is associated with shortened hairs and hair loss, it is referred to as lipedematous alopecia (LA). We report a case of alopecia areata with LS, which may be misdiagnosed as LA. However, the histopathologic features showed a thickened subcutaneous fat layer and hair bulb inflammation. Hair regrowth was appreciable after treatment with topical steroids, minoxidil, oral compound glycyrrhizin, and vitamin D. This case report aims to show that LS and alopecia areata may coexist, and histopathologic examination is necessary for precise diagnosis.

Whole exome sequencing and transcript analysis discover a novel pathogenic splice site mutation in DCAF17 gene underlying Woodhouse-Sakati syndrome

Woodhouse-Sakati syndrome (WSS) is an extremely rare multisystemic disorder with neuroendocrine dysfunctions. It is characterized by hypogonadism, alopecia, diabetes mellitus, intellectual disability and progressive extrapyramidal syndrome along with radiological features of small pituitary gland, progressive frontoparietal white matter changes and abnormal accumulation of iron on globus pallidus. WSS is caused by mutations in DCAF17 gene that encodes for DDB1 and CUL4 associated factor 17. In this study, we report a 17-year-old boy with clinical and radiological features of WSS including mild global developmental delay, mild intellectual disability, sensorineural hearing loss, progressive extrapyramidal syndrome, alopecia, hypogonadotropic hypogonadism and dysmorphic features. Whole exome sequencing analysis revealed a novel potentially pathogenic splice donor site variant (c.458+1G>T) on the intron 4 of DCAF17 gene. Transcript analysis revealed splicing ablation resulting in aberrant splicing of exons 3 and 5 and skipping of exon 4 (c.322_458del). This results in a frameshift and is predicted to cause premature termination of protein synthesis resulting in a protein product of length 120 amino acids (p.[Gly108Ilefs*14]). Our study identified a novel pathogenic variant causing WSS in a patient and expands the spectrum of clinical and genetic characteristics of patients with WSS.

Exploring the effects of Chinese herbal ingredients on the signaling pathway of alopecia and the screening of effective Chinese herbal compounds

ETHNOPHARMACOLOGICAL RELEVANCE

alopecia is a hair disorder that can add a significant medical and psychological burden to patients. Currently, the FDA-approved drugs for the treatment of androgenetic alopecia (AGA) are minoxidil and finasteride and immunosuppressives are therapeutic options for alopecia areata (AA), but the objective adverse effects and high cost of these treatments reduce patient compliance and thus the effectiveness of the drugs. Traditional Chinese medicine (TCM) has good efficacy, a high safety profile and low treatment costs, but its mechanism of action is still not fully understood. The use of signaling pathways to modulate hair loss is a major direction in the study of the pathogenesis and pharmacology of alopecia.

AIM OF THE STUDY

This review aims to collect the results of experimental studies related to alopecia, to screen previously documented combinations of herbs claimed to be effective based on the herbs and their constituent compounds used in the identified studies, and to uncover other useful information that we hope will better guide the clinical application and scientific research of drug combinations or individual herbs for the treatment of alopecia.

MATERIALS AND METHODS

We have reviewed experimental studies to determine the methods used and the mechanisms of action of the herbs and constituent compounds. The following keywords were searched in databases, including PubMed, EMBASE, CNKI and CSTJ." Medicinal plants" "Chinese herbal medicine", "hair loss", " alopecia", "androgenetic alopecia" and " alopecia areata ". We also collected combinations of drugs from books approved by various schools for screening.

RESULTS

Using known combinations of compounds within herbal medicine to match the documented combinations, 34 topical combinations and 74 oral combinations were identified, and among the 108 herbal combinations screened Angelica, Rehmannia glutinosaLigusticum chuanxiong hort, Radix Rehmanniae, etc. The number of occurrences was very high, and the association with vascular drugs was also found to be very close.

CONCLUSIONS

This review further elucidates the therapeutic mechanisms of the compounds within the herbal components associated with alopecia and screens for other combinations that may be dominated by this component for the treatment of alopecia, uncovering compounds from other drugs that may be key factors in the treatment of alopecia. This improvement will provide a better quality of evidence for the effectiveness of herbs and compounds used to treat alopecia.

Dysregulated behaviour of hair follicle stem cells triggers alopecia and provides potential therapeutic targets

Due to a steady increase in the number of individuals suffering from alopecia, this condition has recently received increasing attention. Alopecia can be caused by various pathological, environmental or psychological factors, eventually resulting in abnormalities in hair follicle (HF) structures or HF regeneration disorders, especially dysregulated hair follicle stem cell (HFSC) behaviour. HFSC behaviour includes activation, proliferation and differentiation. Appropriate HFSC behaviour sustains a persistent hair cycle (HC). HFSC behaviour is mainly influenced by HFSC metabolism, ageing, and the microenvironment. In this review, we summarize recent findings on how HFSC metabolism, ageing and the microenvironment give rise to hair growth disorders, as well as related genes and signalling pathways. Recent research on the application of stem cell-based hair tissue engineering and regenerative medicine to treat alopecia is also summarized. Determining how dysregulated HFSC behaviour underlies alopecia would be helpful in identifying potential therapeutic targets.

Adalimumab-Induced Psoriasis with Severe Alopecia

A 52-year-old woman with a 10-pack-year smoking history presented with serious hair loss. She had a 10-year history of Crohn's disease associated with arthritis, for which she had been taking adalimumab. After 2 months of this treatment, she developed pustular lesions on her palms, soles, and scalp. Her gastroenterologist discontinued adalimumab injections, ordered skin biopsy, and switched her to ustekinumab 90-mg subcutaneous injections every 8 weeks. She then presented to our dermatology clinic, 2 months following the initiation of anti-IL12/23 medications, for her alopecia. She had no personal or family history of psoriasis. (SKINmed. 2022;20:136-138).

Follicular Melanocytes in Frontal Fibrosing Alopecia: An Immunohistochemical Study With Trichoscopic Correlation

BACKGROUND

Frontal fibrosing alopecia (FFA) is a scarring alopecia that affects the frontotemporal hairline. Clinically, it may develop with cutaneous hypopigmentation of the affected areas, which has been associated with a reduction in the epidermal melanocyte count. In trichoscopy, peripilar white halos can be observed, which have been associated with fibrosis in other scarring alopecias.

OBJECTIVE

To evaluate the trichoscopic, histopathological and immunohistochemical characteristics of the peripilar white halos in FFA patients.

MATERIALS AND METHODS

We conducted a descriptive cross-sectional study that included 12 patients with FFA presenting peripilar white halos. Two 2-mm punch trichoscopy-guided biopsies were performed in all patients, one fragment for vertical section and another for horizontal section. The vertical sections were stained with Fontana-Mason and Melan-A.

RESULTS

On trichoscopic examination, peripilar white halos ≤ 1 mm in size were observed on the affected scalp. In vertical sections, a reduction in basal melanin pigmentation and a decrease in the melanocyte count in the upper segment of the hair follicle were observed with Fontana-Masson staining and Melan-A immunostaining, respectively.

LIMITATIONS

The small sample size and absence of a control group.

CONCLUSION

This study shows follicular melanocyte involvement in FFA, and this finding may be associated with the peripilar white halos observed in trichoscopy.

Lichen planopilaris and frontal fibrosing alopecia: review and update of diagnostic and therapeutic features

Lichen planopilaris and frontal fibrosing alopecia are primary scarring alopecias where diagnosis can be suggested by clinical and trichoscopy features, especially in the early stages, but scalp biopsy is the standard exam for definitive diagnosis. Frontal fibrosing alopecia is considered a variant of lichen planopilaris, as the histopathological findings are similar, with a perifollicular lymphohistiocytic infiltrate, sometimes with a lichenoid pattern. A thorough clinical examination, trichoscopy and photographic documentation are essential to assess the evolution and therapeutic response. To date, there are no validated treatments or guidelines for these diseases, but there are recommendations that vary with the individual characteristics of each patient. This article presents a comprehensive review of the literature, including an update on topics related to the diagnosis, follow-up, histopathological aspects and available treatments for lichen planopilaris and frontal fibrosing alopecia, highlighting their similarities, differences and peculiarities.

Epidemiology and disease burden of androgenetic alopecia in college freshmen in China: A population-based study

Objective

To evaluate the epidemiology and disease burden of androgenetic alopecia (AGA) in college freshmen in China.

Methods

This population-based cross-sectional survey was carried out among 9227 freshmen of two comprehensive universities in two cities of China (Changsha and Xiamen) from September 2018 to October 2018. Questionnaires covering basic issues, surrounding demographic information, history of diseases, living habits, comorbidities, etc. were completed online in a self-reported manner Dermatological examination was performed by certified dermatologists. The disease burden of AGA, which includes health-related quality of life, symptoms of anxiety, symptoms of depression and quality of sleep, was measured by EQ-5D-3L, PHQ-2, GAD-2 and PSQI, respectively.

Results

The prevalence of AGA in college freshmen in China was 5.3/1000. Male was significantly associated with higher prevalence of AGA (7.9/1000, P<0.01) while female with lower risk of AGA (OR = 0.29, P = 0.002). There was no significant association between BMI and AGA, nor predilection of AGA in the Han nationality or the other ethnic minorities. Annual household income or parental highest educational level exerted no significant influence on the prevalence of AGA. Rosacea (OR = 3.22, P = 0.019) was significantly associated with higher prevalence of AGA while acne seemed not to be related to AGA. The scores of EQ-5D, GAD-2, PHQ-2 and PSQI were not significantly different between students with and without AGA.

Conclusion

The onset of AGA in Chinese college freshmen differ between genders and was significantly associated with rosacea.

Upregulation of androgen receptor by heat shock protein 27 and miR1 induces pathogenesis of androgenic alopecia

OBJECTIVES

The pathogenesis of androgenetic alopecia (AGA) is related to the level of androgen and its metabolic pathways. The binding of androgen and androgen receptor (AR) depends on the assistance of heat shock protein 27 (HSP27). HSP27 combined with microRNAs (miR)-1 can regulate AR levels. However, it is not clear whether HSP27 and miR-1 jointly participate in the pathogenesis of AGA. This study aims to investigate the role of AR up-regulation in the pathogenesis of AGA and underlying mechanisms.

METHODS

A total of 46 male AGA patients (AGA group), who admitted to the First Affiliated Hospital of Guangzhou Medical University from September 2019 to February 2020, and 52 healthy controls admitted to the same period were enrolled in this study. Serum levels of dihydrotestosterone (DHT) and HSP27 in patients and healthy controls were measured by ELISA. Western blotting was used to detect the protein expression of HSP27 and AR in scalp tissues of patients and the healthy controls. The levels of HSP27, AR, and miR-1 were analyzed using real-time PCR. Human dermal papilla cells were transfected with HSP27 siRNA to inhibit the expression of HSP27. MiR-1 and miR-1 inhibitors were transfected simultaneously or separately into cells and then the changes in AR protein expression were detected.

RESULTS

The levels of DHT and HSP27 in the AGA group were (361.4±187.7) pg/mL and (89.4±21.8) ng/mL, respectively, which were higher than those in the control group [(281.8±176.6) pg/mL and (41.2±13.7) ng/mL, both P<0.05]. However, there was no significant difference in serum HSP27 and AR levels among AGA patients with different degrees of hair loss (P>0.05). Correlation analysis showed that there was a positive correlation between HSP27 level and DHT level in the AGA patients (P<0.05). The level of HSP27 mRNA in scalp tissue was negatively correlated with that of miR-1 mRNA (P<0.05). Compared with the control group, the levels of HSP27 protein, AR protein, HSP27 mRNA, and AR mRNA in scalp tissues of AGA group were significantly increased (P<0.05). The up-regulation of HSP27 in scalp tissues of AGA patients was closely related to the increased levels of AR. However, the level of miR-1 in scalp tissues of AGA patients was significantly down-regulated, contrary to the expression of AR (P<0.05). Further in cell studies showed that inhibition of HSP27 or miR-1 expression in human dermal papilla cells could inhibit the expression of AR, and inhibition of both HSP27 and miR-1 expression was found to have an accumulative effect on AR, with statistically significant differences (all P<0.05).

CONCLUSIONS

HSP27 could combine with miR-1 to up-regulate AR levels, which is closely related to the development of AGA.

Treatment of Alopecia in Children

Alopecia or hair loss in children is an important and often challenging problem to diagnose and treat. Early diagnosis and treatment is the key because hair loss in children has a significant physical as well as psychological impact on their development. Alopecia in children are mainly non-scarring, but cicatricial alopecia can also be seen. The diagnosis can usually be made by direct examination of the scalp. Potassium hydroxide (KOH) examination of plucked hair and scalp scrapings, woods lamp examination and trichoscopy are useful diagnostic aids. When a cicatricial alopecia is suspected, scalp biopsy is recommended. Disease specific treatment should be initiated early and adequate counselling provided to both the patient and their parents. This review focuses on the treatment options available for various types of alopecia in children and their safety and efficacy data, analyzing the available literature evidences. J Drugs Dermatol. 2022;21(1):49-53. doi:10.36849/JDD.6096.

Treatment of Alopecia in Children

Alopecia or hair loss in children is an important and often challenging problem to diagnose and treat. Early diagnosis and treatment is the key because hair loss in children has a significant physical as well as psychological impact on their development. Alopecia in children are mainly non-scarring, but cicatricial alopecia can also be seen. The diagnosis can usually be made by direct examination of the scalp. Potassium hydroxide (KOH) examination of plucked hair and scalp scrapings, woods lamp examination and trichoscopy are useful diagnostic aids. When a cicatricial alopecia is suspected, scalp biopsy is recommended. Disease specific treatment should be initiated early and adequate counselling provided to both the patient and their parents. This review focuses on the treatment options available for various types of alopecia in children and their safety and efficacy data, analyzing the available literature evidences. J Drugs Dermatol. 2022;21(1):49-53. doi:10.36849/JDD.6096.

Perspectives on miRNAs Targeting DKK1 for Developing Hair Regeneration Therapy

Androgenetic alopecia (AGA) remains an unsolved problem for the well-being of humankind, although multiple important involvements in hair growth have been discovered. Up until now, there is no ideal therapy in clinical practice in terms of efficacy and safety. Ultimately, there is a strong need for developing a feasible remedy for preventing and treating AGA. The Wnt/β-catenin signaling pathway is critical in hair restoration. Thus, AGA treatment via modulating this pathway is rational, although challenging. Dickkopf-related protein 1 (DKK1) is distinctly identified as an inhibitor of canonical Wnt/β-catenin signaling. Thus, in order to stimulate the Wnt/β-catenin signaling pathway, inhibition of DKK1 is greatly demanding. Studying DKK1-targeting microRNAs (miRNAs) involved in the Wnt/β-catenin signaling pathway may lay the groundwork for the promotion of hair growth. Bearing in mind that DKK1 inhibition in the balding scalp of AGA certainly makes sense, this review sheds light on the perspectives of miRNA-mediated hair growth for treating AGA via regulating DKK1 and, eventually, modulating Wnt/β-catenin signaling. Consequently, certain miRNAs regulating the Wnt/β-catenin signaling pathway via DKK1 inhibition might represent attractive candidates for further studies focusing on promoting hair growth and AGA therapy.

Disruption of the endopeptidase ADAM10-Notch signaling axis leads to skin dysbiosis and innate lymphoid cell-mediated hair follicle destruction

Hair follicles (HFs) function as hubs for stem cells, immune cells, and commensal microbes, which must be tightly regulated during homeostasis and transient inflammation. Here we found that transmembrane endopeptidase ADAM10 expression in upper HFs was crucial for regulating the skin microbiota and protecting HFs and their stem cell niche from inflammatory destruction. Ablation of the ADAM10-Notch signaling axis impaired the innate epithelial barrier and enabled Corynebacterium species to predominate the microbiome. Dysbiosis triggered group 2 innate lymphoid cell-mediated inflammation in an interleukin-7 (IL-7) receptor-, S1P receptor 1-, and CCR6-dependent manner, leading to pyroptotic cell death of HFs and irreversible alopecia. Double-stranded RNA-induced ablation models indicated that the ADAM10-Notch signaling axis bolsters epithelial innate immunity by promoting β-defensin-6 expression downstream of type I interferon responses. Thus, ADAM10-Notch signaling axis-mediated regulation of host-microbial symbiosis crucially protects HFs from inflammatory destruction, which has implications for strategies to sustain tissue integrity during chronic inflammation.

An Approach to Patients with Alopecia

Alopecia is a dermatologic condition in which sudden or gradual loss of hair occurs on 1 or more areas of the body, most commonly the scalp. Hair loss can be acute or chronic in nature as a result of underlying inflammation, autoimmune processes, stressors, chemotherapy, or hairstyling practices. Alopecia can have substantial psychological consequences, having a negative impact on the quality of life in affected patients. The ability to both recognize and distinguish these condition holds great significance not only in providing adequate and timely treatment to improve outcomes but also meeting patient needs.