An overview of JAK/STAT pathways and JAK inhibition in alopecia areata

Small molecule agents against alopecia: Potential targets and related pathways

Alopecia has emerged as a global concern, extending beyond the middle-aged and elderly population and increasingly affecting younger individuals. Despite its growing prevalence, the treatment options and effective drugs for alopecia remain limited due to the incomplete understanding of its underlying mechanisms. Therefore, it is urgent to explore the pathogenesis of alopecia and discover novel and safer therapeutic agents. This review provided an overview of the prevailing clinical disorders of alopecia, and the key pathways and targets involved in hair growth process. Additionally, it discusses FDA-approved drugs and clinical candidates for the treatment of alopecia, and explores small molecule compounds with anti-alopecia potential in the drug discovery phase. These endeavors are expected to provide researchers with valuable scientific insights and practical information for anti-alopecia drug discovery.

Case report: Psoriasiform eczema with immune-mediated comorbidities treated with upadacitinib

Immune-mediated comorbidities in patients with psoriasiform eczema are common. It can be challenging to manage multiple immune-mediated diseases, especially considering that biologic treatments are prone to causing paradoxical effects. The aim of this retrospective observational case series was to describe the course of both psoriasiform eczema and immune-mediated comorbidities in five patients treated with upadacitinib for psoriasiform dermatitis. Five patients, all male, were included. All the patients suffered from psoriasiform eczema. Moreover, two of the patients suffered from alopecia areata, two from vitiligo, one from ulcerative colitis and one from hidradenitis suppurativa. In all cases, the treatment with upadacitinib was rapidly effective on the eczema. The effectiveness on alopecia areata was good in both cases, while the results on vitiligo were only partial. The only case of ulcerative colitis achieved complete remission, while the case of hidradenitis suppurativa experience partial improvement. In conclusion, upadacitinib was effective in treating not only psoriasiform eczema, but also several immune mediated comorbidities. Additional studies are necessary to determine the efficacy of upadacitinib in alopecia areata, vitiligo and hidradenitis suppurativa.

Non-Receptor Tyrosine Kinases: Their Structure and Mechanistic Role in Tumor Progression and Resistance

Protein tyrosine kinases (PTKs) function as key molecules in the signaling pathways in addition to their impact as a therapeutic target for the treatment of many human diseases, including cancer. PTKs are characterized by their ability to phosphorylate serine, threonine, or tyrosine residues and can thereby rapidly and reversibly alter the function of their protein substrates in the form of significant changes in protein confirmation and affinity for their interaction with protein partners to drive cellular functions under normal and pathological conditions. PTKs are classified into two groups: one of which represents tyrosine kinases, while the other one includes the members of the serine/threonine kinases. The group of tyrosine kinases is subdivided into subgroups: one of them includes the member of receptor tyrosine kinases (RTKs), while the other subgroup includes the member of non-receptor tyrosine kinases (NRTKs). Both these kinase groups function as an "on" or "off" switch in many cellular functions. NRTKs are enzymes which are overexpressed and activated in many cancer types and regulate variable cellular functions in response to extracellular signaling-dependent mechanisms. NRTK-mediated different cellular functions are regulated by kinase-dependent and kinase-independent mechanisms either in the cytoplasm or in the nucleus. Thus, targeting NRTKs is of great interest to improve the treatment strategy of different tumor types. This review deals with the structure and mechanistic role of NRTKs in tumor progression and resistance and their importance as therapeutic targets in tumor therapy.

An integrated bioinformatics analysis reveals IRF8 as a critical biomarker for immune infiltration in atherosclerosis advance

Atherosclerosis, a lipid-driven chronic inflammatory disorder, is a significant global health concern associated with high rates of morbidity and mortality, imposing a substantial societal burden. The purpose of this study is to investigate the possible molecular mechanisms of atherosclerosis and identify potential therapeutic targets. We conducted an integrated bioinformatics analysis using data from peripheral blood mononuclear cell and TISSUE databases obtained from the Gene Expression Omnibus, to identify key genes associated with the progression of atherosclerosis. Here, IRF8 was found to be a key gene in atherosclerosis patients. Silencing IRF8 with small interfering RNA reduced inflammation in endothelial cells. This suggests IRF8 is a crucial biomarker for immune infiltration in atherosclerosis advance.

Ferroptosis-Modulating Natural Products for Targeting Inflammation-Related Diseases: Challenges and Opportunities in Manipulating Redox Signaling

Significance: Numerous disorders are linked to ferroptosis, a form of programmed cell death triggered by lipid peroxidation accumulation rather than apoptosis. Inflammation is the body's defensive response to stimuli and is also caused by inflammatory chemicals that can harm the body. The treatment of inflammatory diseases by focusing on the signaling pathways and mechanisms of ferroptosis has emerged as a new area worthy of extensive research. Recent Advances: Studies in cellular and animal models of inflammatory diseases have shown that ferroptosis markers are activated and lipid peroxidation levels are increased. Natural products (NPs) are gaining importance due to their ability to target ferroptosis pathways, particularly the Nuclear factor E2-related factor 2 signaling pathway, thereby suppressing inflammation and the release of pro-inflammatory cytokines. Critical Issues: This article provides an overview of ferroptosis, focusing on the signaling pathways and mechanisms connecting it to inflammation. It also explores the potential use of NPs as a treatment for inflammatory diseases and ferroptosis. Future Directions: NPs offer unique advantages, including multicomponent properties, multi-bio-targeting capabilities, and minimal side effects. Further research may facilitate the early clinical application of NPs to develop innovative treatment strategies.

Comparative efficacy and safety of systemic steroids, oral JAK inhibitors and Contact Immunotherapy in the Treatment of severe alopecia areata: a systematic review and network meta-analysis

Severe alopecia areata (AA) is a nonscarring hair loss for immune disorder and SALT score ≥ 50%. The guidelines for managing patients with severe AA suggest treatments: systemic steroids, JAK inhibitors, and contact immunotherapy. However, there is a lack of evidence indicating the superiority of one treatment over another. Therefore, this study aimed to identify the most effective treatment for severe AA through network meta-analysis. Following the PRISMA guidelines, we conducted a network meta-analysis. The literature search was retrieved across four databases. The Cochrane 5.1 risk of bias assessment tool and ROBINS-I tool assessed quality of the included studies. Subsequently, efficacy and safety comparisons among the three treatments were conducted using Stata 14.0 on account of the frequency method. The SUCRA rank indicated that oral dexamethasone (95.9%) > diphenylcyclopropenone(DPCP) (74.5%) > oral ritlecitinib (62.6%) > oral baricitinib (46.9%) > squaric acid dibutyl ester(SADBE) (20.1%) > placebo (0.0%) from high to low in the aspect of improving efficacy. As for safety, placebo(88.4%) > oral ritlecitinib (86.5%) > oral baricitinib (62.1%) > SADBE (37.0%) > oral dexamethasone(22.3%) > DPCP(3.8%) in the aspect of decreasing adverse events. Oral dexamethasone and DPCP showed superior efficacy compared to oral ritlecitinib and oral baricitinib. However, in terms of safety, oral ritlecitinib was preferable. Some adverse events associated with oral dexamethasone and DPCP were intolerable to patients, whereas those related to oral ritlecitinib and oral baricitinib were more manageable. Overall, ritlecitinib and baricitinib remain promising drugs in the future treatment of severe AA.

Effects of Biomaterials Derived from Germinated Hemp Seeds on Stressed Hair Stem Cells and Immune Cells

Androgenetic alopecia is a genetic disorder that commonly causes progressive hair loss in men, leading to diminished self-esteem. Although cannabinoids extracted from Cannabis sativa are used in hair loss treatments, no study has evaluated the effects of germinated hemp seed extract (GHSE) and exosomes derived from the calli of germinated hemp seeds on alopecia. Therefore, this study aimed to demonstrate their preventive effects against alopecia using various methodologies, including quantitative PCR, flow cytometry, ELISA, and immunocytochemistry. Our research highlights the preventive functions of GHSE (GE2000: 2000 µg/mL) and exosomes from the calli of germinated hemp seeds (E40: 40 μg/mL) in three biochemical categories: genetic modulation in hair follicle dermal papilla stem cells (HFDPSCs), cellular differentiation, and immune system modulation. Upon exposure to dihydrotestosterone (DT), both biomaterials upregulated genes preventing alopecia (Wnt, β-catenin, and TCF) in HFDPSCs and suppressed genes activating alopecia (STAT1, 5α-reductase type 1, IL-15R). Additionally, they suppressed alopecia-related genes (NKG2DL, IL2-Rβ, JAK1, STAT1) in CD8+ T cells. Notably, E40 exhibited more pronounced effects compared to GE2000. Consequently, both E40 and GE2000 effectively mitigated DT-induced stress, activating mechanisms promoting hair formation. Given the limited research on alopecia using these materials, their pharmaceutical development promises significant economic and health benefits.

Atopic diseases and the risk of alopecia areata among pre-teens and teenagers in Taiwan

Background Alopecia areata (AA), a disorder of non-scarring hair loss with a variable relapsing and remitting course, is a common autoimmune disease in children. Although it often presents as several focal small patchy bald lesions, early onset AA can lead to a total loss of scalp hair, even body hairs, a severe subtype. Atopic diseases are common concurrent disorders in AA, especially among those with early onset severe type of hair loss. Whether atopic diseases increase the risk of AA in the paediatric population of Taiwan, remains unclear. Objective To identify if atopic diseases increase the risk of AA among pre-teens and teenagers in Taiwan. Methods From Taiwan National Health Insurance Database 2010, we used the claims data to clarify the risk of AA in pre-teens and teenagers with atopic diseases (atopic dermatitis, allergic conjunctivitis, asthma, allergic rhinitis and food allergy) as compared to the general population. Cox proportional hazards model yielded hazard ratios (HRs) to address the impact of atopic diseases, sex and age on AA risk after adjusting for covariates and subsequent stratified analyses. Results Overall, 21,070 children (10,535 patients with atopic diseases and 10,535 normal cohort) aged over nine years were recruited. During a follow-up of 15 years, 39 (0.37%) cases were identified to have AA in the atopic diseases group, while 11 (0.10%) had developed AA in the normal cohort. As compared with the normal population, the paediatric population with atopic diseases had a 9.66-fold higher risk of developing AA. The risk was greater for boys and increased with advanced age. In the atopic diseases group, pre-teens and teenagers with food allergies and Sjogren's syndrome were more likely to have AA. Limitations Only one ethnic group. Conclusion All atopic diseases enhanced the risk of developing AA in Taiwan pre-teens and teenagers. Children with atopic diseases should be monitored to look for the development of AA.

Serum lipids may causally affect the occurrence of alopecia areata: A Mendelian randomization study

PURPOSE

The etiology of alopecia areata (AA) in relation to serum lipids remains unclear, thereby prompting our intention to do Mendelian study on this subject.

DESIGN

Two-sample Mendelian randomization (MR) analysis was performed in the study. The inverse variance-weighted method was used as the primary method.

METHODS

In our study, we integrated a set of 123 single-nucleotide polymorphisms (SNPs) into our analysis. These SNPs have been extensively studied and are known to exhibit associations with serum lipids. We sourced these SNPs from a variety of relevant studies and consortia that specifically focus on lipid-related research, such as the MRC Integrative Epidemiology Unit. These carefully curated SNPs were then utilized as instrumental variables in our analysis, allowing us to explore and evaluate the causal relationships between these genetic variants and serum lipids. By incorporating this comprehensive set of SNPs, we aimed to enhance the precision and robustness of our findings, shedding light on the intricate interplay between genetics and serum lipids.

RESULTS

In the MR analysis, a higher total lipid concentration in large low-density lipoprotein (LDL) particles (odds ratio [OR] = 1.502; 95% confidence interval [CI] = 1.086-1.953; p = 0.006), a greater ratio of cholesteryl esters to total lipids in chylomicrons and extremely large very LDL (VLDL) particles (OR = 2.174; 95% CI = 1.300-2.500; p = 0.010), and a greater ratio of cholesterol to total lipids in chylomicrons and extremely large VLDL particles (OR = 2.363;95% CI = 1.556-4.438; p = 0.004), were genetically predicted to be causally associated with an increased risk of AA, while patients with a higher triglyceride to total lipids ratio in chylomicrons and extremely large VLDL particles had a lower risk of AA (OR = 0.481; 95% CI = 0.191-1.270; p = 0.002).

CONCLUSION

This study found that serum lipids may be causally implicated in AA.

A Review of JAK Inhibitors for Treatment of Alopecia Areata in the Military Health Care System

INTRODUCTION

Alopecia areata (AA) is a disease that manifests as patchy hair loss on the scalp and other parts of the body; severe disease may result in disfigurement, functional impairment, and significant psychological distress. This condition is understood to be caused by autoimmunity to the hair follicle and subsequent arrest of hair growth. New medications, baricitinib and ritlecitinib, belong to the Janus kinase (JAK) inhibitor family and are among the first FDA-approved treatments for severe AA. In this manuscript, we aim to answer the question: What treatment options exist for AA in the military health care system (MHS)? In doing so, we review the pathogenesis, physical and psychosocial impact of AA, conventional treatment of AA, and the efficacy and safety of baricitinib and ritlecitinib.

METHODS

A literature search was performed using PubMed, Embase, and Ovid for the history and pathogenesis of AA, psychosocial impact of disease, functional impairments, and current treatments. Keywords "alopecia areata," "current therapy for alopecia areata," "pathogenesis alopecia areata," "baricitinib," "ritlecitinib," "JAK inhibitor alopecia," "JAK inhibitor safety," "baricitinib efficacy," "alopecia eyelash," "alopecia nails," and "psychosocial impact of alopecia" were used for the search. The TRICARE manual was searched for guidelines applicable to the treatment of AA, DoD Instruction 6130.03 Volume 2 for medical standards for military service, and the U.S. Central Command Modification 15 for fitness of deployment to Central Command area of operations.

RESULTS

Traditional treatments such as intralesional steroids may be effective for some patients, but difficulty lies in controlling extensive or refractory disease. Janus kinase inhibitors, baricitinib and ritlecitinib, are found effective at improving severe refractory disease; baricitinib induced hair regrowth in 32.6% more patients than placebo, and ritlecitinib was found to be superior to placebo by at least 24%. Currently, there is no coverage for therapeutic treatment of hair growth in the MHS. Additionally, military members are disqualified for continued service if they require immunomodulator medications such as baricitinib and ritlecitinib. Those on immunomodulators are unable to deploy worldwide.

CONCLUSIONS

Baricitinib and ritlecitinib are effective treatments for widespread, progressive, and refractory AA. Although JAK inhibitors demonstrate improved effectiveness compared to non-immunomodulator treatments, their use in the MHS for this purpose is limited.

Case report: Sequential therapy with dupilumab and baricitinib for severe alopecia areata with atopic dermatitis in children

An 8-year-old female child presented with patchy hair loss for 1 year, accompanied by eyebrow loss for 6 months. Microscopic examination of the hair confirmed the features of active stage alopecia areata, with a Severity of Alopecia Tool (SALT) score of 70%. The diagnosis was severe alopecia areata. The patient had a history of atopic dermatitis since infancy, with recurrent episodes of scattered papules and pruritus for 8 years. Initial treatment involved subcutaneous injections of dupilumab 300mg every 2 weeks for 6 months, resulting in a reduction of SALT score to 20% and improvement of atopic dermatitis symptoms. Discontinuation of Dupilumab and initiation of daily oral Baricitinib at a dose of 2mg for a duration of 5 months. According to the SALT score evaluation, the severity of hair loss was less than 10% and there was significant regrowth of hair. No significant adverse reactions were observed during the treatment period.

Elevation of circulating DNAs of disease-associated cytokines in serum cell-free DNA from patients with alopecia areata

Alopecia areata (AA) is an autoimmune disease characterized by damage to hair follicles and hair loss. Cell-free DNA (cfDNA) has recently received attention as a biomarker of various disorders including inflammatory skin diseases. In this study, we aimed to investigate the clinical significance of cfDNA and the circulating DNAs of disease-associated cytokines in AA patients. Serum samples were obtained from 63 patients with AA and 32 healthy controls (HC). Using droplet digital polymerase chain reaction, circulating C-X-C motif chemokine ligand (CXCL) 9, CXCL10, CXCL11, C-X-C motif chemokine receptor 3, interferon (IFN)-γ, interleukin (IL) -7, IL-15, and Janus kinase (JAK) 2 were detectable in both HC and AA patients. Among the detectable DNAs, copies of circulating CXCL9, CXCL11, IL-15, IFN-γ, and JAK2 were significantly higher in AA patients than in HC. These results suggest that increased circulating DNA levels may reflect damage to hair follicles in AA patients.

Treatment Challenges in Alopecia Areata: Insights From a Case of Baricitinib Therapy Failure

Alopecia areata (AA) has long been considered a challenging clinical condition, with dermatologists traditionally employing corticosteroids and immunosuppressants in search of effective solutions. The introduction of Janus kinase inhibitors (JAKi), specifically the Food and Drug Administration (FDA) approval of baricitinib, marked a significant breakthrough in the treatment of AA. Clinical trials have shown promising results with baricitinib, and reports of relapse after initial success are scarce. We present a unique case of a 30-year-old male with severe patch-type AA who initially responded well to baricitinib treatment but later experienced a relapse despite continued treatment.

Research trends in alopecia areata: a cross-sectional bibliometric analysis of the top cited studies

In the field of alopecia areata research, various focuses including risk factors, epidemiology, molecular pathways, and treatment were constantly improving. However, to date, a bibliometric analysis summarizing the research trend is not available to date. The main objective of this study was to provide researchers with an overview of the research trend on alopecia areata in the past two decades. In Web of Science database, screening and extraction of studies related to alopecia areata has been performed. Within studies related to alopecia areata, the most cited 100 studies were appraised and the information of articles, including the citation amounts, keywords and publication types, was extracted for analyses. On average, each study in the top 100 list was cited 104.72 times. Within the top 100 list, the most focused fields were on the management of alopecia areata (34%), molecular mechanisms (28%) and epidemiological issues (23%). Approximately one third of the management-associated studies focused on Janus kinase (JAK) inhibitors (10 studies) and 5 studies focused on the efficacy of corticosteroids for alopecia areata. According to the results of the keyword analysis, JAK inhibitors had become the most mentioned keywords in the field of alopecia areata research since 2016. The top 100 most referenced papers in the field of alopecia areata mostly focused on essential aspects such as treatment options, pathogenesis, risk factors, and comorbidities. The results of the current study could be considered a potential resource for future research and patient care information.

Deciphering the Complex Immunopathogenesis of Alopecia Areata

Alopecia areata (AA) is an autoimmune-mediated disorder in which the proximal hair follicle (HF) attack results in non-scarring partial to total scalp or body hair loss. Despite the growing knowledge about AA, its exact cause still needs to be understood. However, immunity and genetic factors are affirmed to be critical in AA development. While the genome-wide association studies proved the innate and acquired immunity involvement, AA mouse models implicated the IFN-γ- and cytotoxic CD8+ T-cell-mediated immune response as the main drivers of disease pathogenesis. The AA hair loss is caused by T-cell-mediated inflammation in the HF area, disturbing its function and disrupting the hair growth cycle without destroying the follicle. Thus, the loss of HF immune privilege, autoimmune HF destruction mediated by cytotoxic mechanisms, and the upregulation of inflammatory pathways play a crucial role. AA is associated with concurrent systemic and autoimmune disorders such as atopic dermatitis, vitiligo, psoriasis, and thyroiditis. Likewise, the patient's quality of life (QoL) is significantly impaired by morphologic disfigurement caused by the illness. The patients experience a negative impact on psychological well-being and self-esteem and may be more likely to suffer from psychiatric comorbidities. This manuscript aims to present the latest knowledge on the pathogenesis of AA, which involves genetic, epigenetic, immunological, and environmental factors, with a particular emphasis on immunopathogenesis.

Safety and efficacy of tofacitinib in 97 alopecia areata patients

BACKGROUND

Alopecia areata (AA) is a recurrent immune-mediated disorder causing hair loss without any scarring being present. It affects hairs on the head or other parts of the body and can occur at any age and in both genders. It seems that AA is associated with a higher rate of psychological disorders resulting from hair loss and the esthetic and social repercussions of it. Common treatments like corticosteroids do not work for every patient and recent treatment options focusing on the immunologic mechanisms like tofacitinib have shown some promising results.

METHODS

It's a retrospective study on patients with AA, AT, AU taking oral tofacitinib as a treatment for at least 6 months. Scalp hair loss was assessed before treatment and at each visit using the Severity of Alopecia Tool (SALT) score.

RESULTS

Of 97 cases, 69.1% demonstrated over 50% SALT score improvement, with 44.3% having 90% or more decrease in SALT score. Patients who suffered from patchy AA were more responsive compared to patients with AT and AU subtypes and had a greater percent change in SALT score. Tofacitinib was tolerated quite well and no significant adverse events were reported.

CONCLUSIONS

Tofacitinib should be taken into consideration as an efficacious treatment option for patients with AA, AT and AU.

Novel investigational drugs for alopecia areata and future perspectives

INTRODUCTION

Alopecia areata (AA) is an immune-mediated disease that causes non-scarring hair loss. While acute, solitary patches often spontaneously remit, developing secondary patches or failure of the disease to resolve within 6-12 months predicts a poor prognosis, with an increased risk of alopecia totalis or universalis. Chronic AA increases the risk of depression and suicidality and reduces quality of life. Treatment options for chronic or acute diffuse AA were previously limited to corticosteroids and traditional immunomodulators. Two Janus Kinase (JAK) inhibitors are now approved for the treatment of chronic AA.

AREAS COVERED

The results of landmark phase 3 trials for three JAK inhibitors, baricitinib, ritlecitinib, and deuruxolitinib are discussed. Evidence for other JAK inhibitors, biologics, and phosphodiesterase-4 inhibitors are also presented. Therapies currently undergoing clinical trials are listed.

EXPERT OPINION

JAK inhibitors are a safe and efficacious treatment of moderate-to-severe AA. Early intervention, regardless of severity, allows for improved treatment efficacy. It is uncertain how long patients should remain on JAK inhibitors; discontinuation often leads to relapse. A black-box warning for JAK inhibitors was extrapolated from safety data in a rheumatoid arthritis cohort; recent meta-analyses of JAK inhibitors used in dermatology cohorts do not demonstrate the same risk profile.

Interleukin-15 is a hair follicle immune privilege guardian

The autoimmunity-promoting cytokine, Interleukin-15 (IL-15), is often claimed to be a key pathogenic cytokine in alopecia areata (AA). Yet, rhIL-15 promotes human hair follicle (HF) growth ex vivo. We have asked whether the expression of IL-15 and its receptor (IL-15R) isoforms is altered in human AA and how IL-15 impacts on human HF immune privilege (HF-IP) in the presence/absence of interferon-γ (IFNγ), the well-documented key AA-pathogenic cytokine, as well as on hair regrowth after experimental AA induction in vivo. Quantitative immunohistomorphometry showed the number of perifollicular IL-15+ T cells in AA skin biopsies to be significantly increased compared to healthy control skin, while IL-15, IL-15Rα, and IL-15Rγ protein expression within the hair bulb were significantly down-regulated in AA HFs. In organ-cultured human scalp HFs, rhIL-15 significantly reduced hair bulb expression of MICA, the key "danger" signal in AA pathogenesis, and increased production of the HF-IP guardian, α-MSH. Crucially, ex vivo, rhIL-15 prevented IFNγ-induced HF-IP collapse, restored a collapsed HF-IP by IL-15Rα-dependent signaling (as documented by IL-15Rα-silencing), and protected AA-preventive immunoinhibitory iNKT10 cells from IFNγ-induced apoptosis. rhIL-15 even promoted hair regrowth after experimental AA induction in human scalp skin xenotransplants on SCID/beige mice in vivo. Our data introduce IL-15 as a novel, functionally important HF-IP guardian whose signaling is constitutively defective in scalp HFs of AA patients. Our data suggest that selective stimulation of intrafollicular IL-15Rα signaling could become a novel therapeutic approach in AA management, while blocking it pharmacologically may hinder both HF-IP restoration and hair re-growth and may thus make HFs more vulnerable to AA relapse.

Genomic Inbreeding and Runs of Homozygosity Analysis of Cashmere Goat

Cashmere goats are valuable genetic resources which are famous worldwide for their high-quality fiber. Runs of homozygosity (ROHs) have been identified as an efficient tool to assess inbreeding level and identify related genes under selection. However, there is limited research on ROHs in cashmere goats. Therefore, we investigated the ROH pattern, assessed genomic inbreeding levels and examined the candidate genes associated with the cashmere trait using whole-genome resequencing data from 123 goats. Herein, the Inner Mongolia cashmere goat presented the lowest inbreeding coefficient of 0.0263. In total, we identified 57,224 ROHs. Seventy-four ROH islands containing 50 genes were detected. Certain identified genes were related to meat, fiber and milk production (FGF1, PTPRM, RERE, GRID2, RARA); fertility (BIRC6, ECE2, CDH23, PAK1); disease or cold resistance and adaptability (PDCD1LG2, SVIL, PRDM16, RFX4, SH3BP2); and body size and growth (TMEM63C, SYN3, SDC1, STRBP, SMG6). 135 consensus ROHs were identified, and we found candidate genes (FGF5, DVL3, NRAS, KIT) were associated with fiber length or color. These findings enhance our comprehension of inbreeding levels in cashmere goats and the genetic foundations of traits influenced by selective breeding. This research contributes significantly to the future breeding, reservation and use of cashmere goats and other goat breeds.

Comparative efficacy and safety of JAK inhibitors in the treatment of moderate-to-severe alopecia areata: a systematic review and network meta-analysis

We performed a Bayesian network meta-analysis to indirectly compare the relative efficacy and safety of the latest JAK inhibitors for moderate-to-severe alopecia areata (AA). 13 trials totaling 3,613 patients were included. Two low-dose groups of oral formulations (ritlecitinib 10mg and ivarmacitinib 2mg) and two topical formulations (delgocitinib ointment and ruxolitinib cream) appeared to be relatively ineffective against moderate-to-severe AA. Ranking analysis suggested that brepocitinib 30mg has the best relative effect in reducing the SALT score (sucra = 0.9831), and demonstrated comparable efficacy to deuruxolitinib 12mg (sucra = 0.9245), followed by deuruxolitinib 8mg (sucra = 0.7736). Regarding the SALT50 response, brepocitinib 30mg ranked highest (sucra = 0.9567), followed by ritlecitinib 50mg (sucra = 0.8689) and deuruxolitinib 12mg (sucra = 0.7690). For achieving the SALT75 response, deuruxolitinib 12mg had the highest probability (sucra = 0.9761), followed by deuruxolitinib 8mg (sucra = 0.8678) and brepocitinib 30mg (sucra = 0.8448). Deuruxolitinib 12mg might be the most effective therapy for patients with severe AA (sucra = 0.9395), followed by ritlecitinib 50mg (sucra = 0.8753) and deuruxolitinib 8mg (sucra = 0.8070). Deuruxolitinib 12mg/8mg demonstrated notable efficacy for moderate-to-severe AA, and is expected to be a new treatment option for AA. It was worth noting that deuruxolitinib exhibit a greater likelihood of causing adverse events in comparison to other JAK inhibitors. Ritlecitinib 50mg seemed to exhibit fewer adverse effects in the high-dose groups of oral JAK inhibitors and might be an optimal choice to balance safety and efficacy. The majority of JAK inhibitors exhibited acceptable short-term safety profiles. To enhance the applicability and accuracy of our research, further head-to-head trials with longer follow-up periods are needed. Systematic Review Registration: identifier [CRD42022368012].

Involvement of DKK1 secreted from adipose-derived stem cells in alopecia areata

Adipose-derived stem cells (ASCs) have shown efficacy in promoting hair growth, while DKK1 inhibits the WNT pathway, which is associated with hair loss. Our study focused on investigating the expression of DKK1 in alopecia areata (AA), a condition characterised by significant increases in the DKK1 levels in human and mouse ASCs. Treatment of interferon-γ increased the expression of DKK1 via STAT3 phosphorylation in ASCs. Treatment with recombinant DKK1 resulted in a decrease of cell growth in outer root sheath cells, whereas the use of a DKK1 neutralising antibody promoted hair growth. These results indicate that ASCs secrete DKK1, playing a crucial role in the progression and development of AA. Consequently, we generated DKK1 knockout (KO) ASCs using the Crispr/Cas9 system and evaluated their hair growth-promoting effects in an AA model. The DKK1 KO in ASCs led to enhanced cell motility and reduced cellular senescence by activating the WNT signalling pathway, while it reduced the expression of inflammatory cytokines by inactivating the NF-kB pathway. As expected, the intravenous injection of DKK1-KO-ASCs in AA mice, and the treatment with a conditioned medium derived from DKK1-KO-ASCs in hair organ culture proved to be more effective compared with the use of naïve ASCs and their conditioned medium. Overall, these findings suggest that DKK1 represents a novel therapeutic target for treating AA, and cell therapy using DKK1-KO-ASCs demonstrates greater efficiency.

MiR-200c-3p as a novel genetic marker and therapeutic tool for alopecia areata

BACKGROUND

MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression in diverse biological processes. They hold promise as therapeutic candidates for targeting human disease pathways, although our understanding of their gene regulatory mechanism remains incomplete. Alopecia areata (AA) is a prevalent inflammatory ailment distinguished by the infiltration of T cells targeting the anagen-stage hair follicles. The scarcity of effective remedies for AA may stem from limited understanding regarding its precise cellular mechanism.

AIM

To investigate and examine the importance and role of the miR-200c-3p as a genetic indicator for AA, and its possible impact on disease progression.

SUBJECTS AND METHODS

Case-control study included 65 patients with AA and 65 matched healthy controls. A real-time PCR technique was used to measure the expression of miR-200c-3p for both groups. Bioinformatic tools were used for prediction with genes and gene-gene interaction, and protein-protein interaction.

RESULTS

The expression levels of miR-200c-3p were significantly higher in AA patients than in healthy controls. We predicted that miR-200c-3p plays a markable role in the development of AA by its effect on the EGFR tyrosine kinase inhibitor resistance pathway.

CONCLUSION

We were able to identify the influence of miR-200c-3p on both PLCG1 and RPS6KP1 genes which in turn regulate the EGFR tyrosine kinases resistance pathway that displayed the most substantial increase in activity. Our outcomes shed light on the era of the potential theranostic role of this innovative miRNA in AA.

Alopecia areata: What's new in the diagnosis and treatment with JAK inhibitors?

Alopecia areata (AA) affects individuals of all ages and is intractable in severe relapsing cases. Dermatologists and other healthcare providers should consider AA in the medical context and prioritize treatment. Several randomized controlled clinical studies on Janus kinase (JAK) inhibitors with different specificities for the treatment of AA are ongoing. These studies have encouraged us to appreciate the importance of a definitive diagnosis and accurate evaluation of AA before and during treatment. Following our previous review article in 2017, here we provide the second part of this two-review series on the recent progress in the multidisciplinary approaches to AA from more than 1800 articles published between July 2016 and December 2022. This review focuses on the evaluation, diagnosis, and treatment of AA. We also provide the latest information on the safety and efficacy of JAK inhibitors for the treatment of AA and describe their mechanisms of action.

Effectiveness and Predictive Factors of Response to Tofacitinib Therapy in 125 Patients with Alopecia Areata: A Single-centre Real-world Retrospective Study

Alopecia areata is an autoimmune disorder that greatly impacts patients' quality of life, and its management remains challenging. Tofacitinib is the first Janus kinase inhibitor to be approved for clinical use and is the most extensively studied. Several studies have demonstrated the clinical effectiveness of oral tofacitinib in treating patients with alopecia areata. However, despite being widely used in clinical practice, no prospective randomized controlled trials have been implemented and its indication criteria have not been thoroughly established. Moreover, little is known about the factors associated with response to therapy under real-world conditions. The aims of this retrospective cohort study of patients with alopecia areata treated with tofacitinib for 3 months were to assess the effectiveness of tofacitinib and to identify predictive factors of response to it. Primary outcome was the change in disease severity, as evaluated by Severity of Alopecia Tool (SALT) grade. A total of 125 patients with alopecia areata were included, the incidence of effectiveness was 83.2%, and 16.0% of patients achieved a result of complete remission. Total duration of alopecia areata and previous hair regrowth were independent predictors of response. Combined therapy was associated with relapse after discontinuation. No severe adverse event was observed. This study suggests that tofacitinib provides an effective treatment option for patients with alopecia areata, and that earlier intervention in the treatment of severe alopecia areata with tofacitinib may lead to better outcomes.

Novel Janus Kinase Inhibitors in the Treatment of Dermatologic Conditions

Janus kinase inhibitors, also known as JAK inhibitors, JAKinibs or JAKi, are a new group of disease-modifying drugs. They work by inhibiting enzymes involved in the transmission of information from receptors located in the cell membrane to the cell interior, specifically to the cell nucleus, thus disrupting the JAK-STAT pathway. This pathway plays a role in key cellular processes such as the immune response and cell growth. This feature is used in the treatment of patients with rheumatological, gastroenterological and hematological diseases. Recently, it has been discovered that JAK-STAT pathway inhibitors also show therapeutic potential against dermatological diseases such as atopic dermatitis, psoriasis, alopecia areata and acquired vitiligo. Studies are underway to use them in the treatment of several other dermatoses. Janus kinase inhibitors represent a promising class of drugs for the treatment of skin diseases refractory to conventional therapy. The purpose of this review is to summarize the latest knowledge on the use of JAKi in dermatological treatment.

Drug Survival and Long-term Outcome of Tofacitinib in Patients with Alopecia Areata: A Retrospective Study

Several non-randomized clinical trials and retrospective studies have demonstrated encouraging efficacy and well-tolerated safety of tofacitinib in the treatment of alopecia areata. However, there are scarce data on a large cohort of patients with alopecia areata in long-term real-world practice. This single-centre, retrospective, observational cohort study included 126 patients with alopecia areata treated with tofacitinib between February 2021 and December 2022. The aims of this study are to evaluate drug survival, effectiveness and safety of tofacitinib for treatment of alopecia areata, and to identify potential factors influencing long-term outcomes. Median duration of treatment was 23.00 (interquartile range (IQR) 15.00, 47.25) weeks. Median all-cause survival time of 126 patients treated with tofacitinib was 44 weeks (95% confidence interval (95% CI) 36.3, 51.7), and the all-cause drug retention rate at 12 weeks, 24 weeks and 48 weeks were 90.0%, 66.4% and 42.3%, respectively. The most common reason for discontinuation was complete remission/satisfaction. A total of 80 patients treated with tofacitinib for over 6 months were included in the efficacy analysis, the overall complete response rate at 24 weeks was 33.8% (27/80). No life-threatening serious adverse events occurred. Sex is an independent risk factor in predicting patient outcomes. This real-world study confirmed the high effectiveness and acceptable safety profile of tofacitinib in alopecia areata, with a satisfactory drug survival rate, and provides supporting data for the clinical application of tofacitinib in Chinese patients with alopecia areata.

Inhibition of T-cell activity in alopecia areata: recent developments and new directions

Alopecia areata (AA) is an autoimmune disease that has a complex underlying immunopathogenesis characterized by nonscarring hair loss ranging from small bald patches to complete loss of scalp, face, and/or body hair. Although the etiopathogenesis of AA has not yet been fully characterized, immune privilege collapse at the hair follicle (HF) followed by T-cell receptor recognition of exposed HF autoantigens by autoreactive cytotoxic CD8+ T cells is now understood to play a central role. Few treatment options are available, with the Janus kinase (JAK) 1/2 inhibitor baricitinib (2022) and the selective JAK3/tyrosine kinase expressed in hepatocellular carcinoma (TEC) inhibitor ritlecitinib (2023) being the only US Food and Drug Administration-approved systemic medications thus far for severe AA. Several other treatments are used off-label with limited efficacy and/or suboptimal safety and tolerability. With an increased understanding of the T-cell-mediated autoimmune and inflammatory pathogenesis of AA, additional therapeutic pathways beyond JAK inhibition are currently under investigation for the development of AA therapies. This narrative review presents a detailed overview about the role of T cells and T-cell-signaling pathways in the pathogenesis of AA, with a focus on those pathways targeted by drugs in clinical development for the treatment of AA. A detailed summary of new drugs targeting these pathways with expert commentary on future directions for AA drug development and the importance of targeting multiple T-cell-signaling pathways is also provided in this review.

Identifying immuno-related diagnostic genes and immune infiltration signatures for periodontitis and alopecia areata

BACKGROUND

Although there have been indications that periodontitis (PD) may be susceptible to alopecia areata (AA), the underlying mechanism of its pathogenesis remains poorly understood. The objective of our study is to conduct further research into the occurrence of this complication.

METHODS

The gene expression omnibus (GEO) database was the source of acquisition for both PD and AA datasets. Various methods, including the differentially expressed genes (DEGs) analysis, functional enrichment analysis, protein-protein interaction (PPI) network construction, Cytohubba algorithms, and RandomForest algorithms, were utilized to identify candidate hub immuno-related genes (IRGs) for diagnosing AA with PD. The diagnostic efficacy was assessed by constructing receiver operating characteristic (ROC) curves. To further deepen our understanding, immune cell infiltration, flow cytometry assay, and immunofluorescence techniques were employed to uncover immune cell dysregulation in PD and AA.

RESULTS

899 and 803 DEGs were detected in AA and PD, respectively, with an intersection of 150 common DEGs enriched in immune regulation. Further analysis of the junction of shared DEGs and IRGs was analyzed using the PPI network, Mcode, and Cytohubba algorithms. Three hub genes (CTSS, IL2RG, and ITGAL) were subsequently selected by Cytohubba and RandomForest algorithms and were found to be promising candidate hub genes with high diagnostic values (AUC ranging from 0.776 to 0.909) for diagnosing AA with PD. Additionally, various dysregulated immune cells were observed, with mast cells potentially serving as markers for AA and plasma for PD.

CONCLUSION

Three candidate hub IRGs (CTSS, IL2RG, and ITGAL) were identified with considerable diagnostic values. Besides, mast cells could serve as markers for AA, while plasma may indicate PD. Our research has the potential to identify shared diagnostic candidate genes and immune cells for AA and PD patients.

Janus kinase inhibitors for alopecia areata: A narrative review

The Janus kinase (JAK) and Signal Transducer and Activator of Transcription (STAT) pathway has been identified as a key player in the pathophysiology of alopecia areata and a potential target for therapy. Here, we give a narrative review of what is known about Janus kinase inhibitors in alopecia areata. Several clinical trials as well as smaller studies have demonstrated hair regrowth and remission with oral Janus kinase inhibitors therapy, even in patients who failed conventional treatment. Baricitinib is the only US FDA-approved treatment for alopecia areata but data for other oral Janus kinase inhibitors such as tofacitinib, ruxolitinib and ritlecitinib are also promising. Fewer clinical trials have investigated topical Janus kinase inhibitors for alopecia areata, with many of them terminated early due to unfavourable results. Overall, Janus kinase inhibitors are an efficacious addition to the therapeutic arsenal for treatment-refractory alopecia areata. Further work is needed to examine the effects of long-term usage of Janus kinase inhibitors, the efficacy of topical Janus kinase inhibitors, as well as to identify biomarkers that could predict differential therapeutic responses to the various Janus kinase inhibitors.

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.

Genetically predicted levels of circulating cytokines and the risk of six immune skin diseases: a two-sample Mendelian randomization study

Background

Circulating cytokines play a crucial role in the onset and progression of immune skin diseases. However, the causal relationships and the direction of causal effects require further investigation.

Methods

Two-sample Mendelian randomization (MR) analyses were conducted to assess the causal relationships between 41 circulating cytokines and six immune skin diseases including alopecia areata, chloasma, hidradenitis suppurativa (HS), lichen planus (LP), seborrheic dermatitis, and urticaria, using summary statistics from genome-wide association studies. Reverse MR analyses was performed to test for the reverse causation. Pleiotropy and heterogeneity tests were conducted to assess the robustness of the findings.

Results

Twelve unique cytokines showed a suggestive causal relationship with the risk of six immune skin diseases. Among them, the causal effects between 9 unique cytokines and immune skin diseases have strong statistical power. Additionally, the concentrations of six cytokines might be influenced by LP and urticaria. After Bonferroni correction, the following associations remained significant: the causal effect of beta-nerve growth factor on HS (odds ratio [OR] = 1.634, 95% confidence interval [CI] = 1.226-2.177, p = 7.97e-04), interleukin (IL)-6 on LP (OR = 0.615, 95% CI = 0.481-0.786, p = 1.04e-04), IL-4 on LP (OR = 1.099. 95% CI = 1.020-1.184, p = 1.26e-02), and IL-2 on urticaria (OR = 0.712, 95% CI = 0.531-0.955, p = 2.33e-02).

Conclusion

This study provides novel perspectives on the relationship between circulating cytokines and immune skin diseases, potentially providing valuable insights into their etiology, diagnostic approaches, and treatment.

Inflammatory loops in the epithelial-immune microenvironment of the skin and skin appendages in chronic inflammatory diseases

The epithelial-immune microenvironment (EIME) of epithelial tissues has five common elements: (1) microbial flora, (2) barrier, (3) epithelial cells, (4) immune cells, and (5) peripheral nerve endings. EIME provides both constant defense and situation-specific protective responses through three-layered mechanisms comprising barriers, innate immunity, and acquired immunity. The skin is one of the largest organs in the host defense system. The interactions between the five EIME elements of the skin protect against external dangers from the environment. This dysregulation can result in the generation of inflammatory loops in chronic inflammatory skin diseases. Here, we propose an understanding of EIME in chronic skin diseases, such as atopic dermatitis, psoriasis, systemic lupus erythematosus, alopecia areata, and acne vulgaris. We discuss the current treatment strategies targeting their inflammatory loops and propose possible therapeutic targets in the future.

Efficacy and safety of baricitinib in patients with alopecia areata: evidence to date

Alopecia areata (AA) is a chronic, tissue-specific autoimmune disorder, characterized by non-scaring hair loss, with a global prevalence of approximately 2%. Typically, it affects a young population, with initial onset frequently occurring before the age of 30 years. Even though the exact pathogenesis of AA remains unclear, the predominant hypothesis is the breakdown of immune privilege of the hair follicle, resulting in increased self-antigen and major histocompatibility complex expression in the follicular epithelium. The relapsing nature of the disease negatively impacts patients' quality of life and makes them more susceptible to developing psychiatric comorbidities. Although many treatment modalities have been proposed, there are no currently available treatments able to induce and sustain disease remission. Traditional treatment modalities, despite being widely used, present limited results and a high risk of adverse effects. Hence, there exists an unfulfilled requirement for treatments that are both more efficient and safer. The latest understanding of the pathophysiology of AA and its connection to the JAK-STAT pathway has prompted the advancement of JAK inhibitors. These small-molecule agents function by obstructing the JAK-STAT intracellular signalling pathway. Baricitinib an orally administered, selective JAK1 and JAK2 inhibitor is a promising alternative to the available treatments, and is already approved for the treatment of AA.

Genome-Wide Association Study of Alopecia Areata in Taiwan: The Conflict Between Individuals and Hair Follicles

Purpose

Alopecia areata (AA) is one of the most prevalent autoimmune diseases affecting humans. Given that hair follicles are immune-privileged, autoimmunity can result in disfiguring hair loss. However, the genetic basis for AA in the Taiwanese population remains unknown.

Materials and Methods

A genome-wide association study was conducted using a cohort of 408 AA cases and 8167 controls. To link variants to gene relationships, we used 882 SNPs (P<1E-05) within 74 genes that were associated with AA group to build the biological networks by IPA software. HLA diplotypes and haplotypes were analyzed using Attribute Bagging (HIBAG)-R package and chi-square analysis.

Results

Seven single nucleotide polymorphisms (SNPs) including LINC02006 (rs531166736, rs187306735), APC (rs112800832_C_CAT), SRP19 (rs139948960, rs144784670), EGFLAM (rs16903975) and LDLRAD3 (rs79874564) were closely associated with the AA phenotype (P<5E-08). Examination of biological networks revealed that these genomic areas are associated with antigen presentation signaling, B cell and T cell development, Th1 and Th2 activation pathways, Notch signaling, crosstalk signaling between dendritic cells and natural killer cells, and phagosome maturation. Based on human leukocyte antigen (HLA) genotype analysis, four HLA genotypes (HLA-B*15:01-*40:01, HLA-DQA1*01:02-*03:03, HLA-DQA1*01:02, and HLA-DQB1*02:01) were found to be associated with AA (adjusted p-value<0.05). HLA-DQA1*01:02 is the most significantly related gene in the Taiwanese population (adjusted p-value = 2.09E-05).

Conclusion

This study successfully identified susceptibility loci associated with AA in the Taiwanese population. These findings not only shed light on the origins of AA within the Taiwanese context but also contribute to a comprehensive understanding of the genetic factors influencing AA susceptibility.

Effectiveness of Tofacitinib in Pre-adolescent Alopecia Areata: A Retrospective Case Series and Literature Review

Alopecia areata (AA) is a common cause of hair loss in children. Despite numerous therapeutic options for paediatric AA, none have been found to be both effective and safe. Recent studies have demonstrated the efficacy and safety of the Janus kinase (JAK) inhibitor tofacitinib in adult patients with AA, whereas data on paediatric patients with AA in real-world practice are limited. This was a single-centre, retrospective study that included 11 pre-adolescent patients with AA treated with tofacitinib between December 2021 and September 2022. Clinical characteristics of patients, clinical response and adverse events were evaluated. Overall, 82% (9/11) of patients experienced hair regrowth and 64% (7/11) of patients experienced over 50% improvement in their Severity of Alopecia Tool (SALT) scores. Adverse events were mild. In the literature, tofacitinib has been used to treat AA in 31 children ≤12 years of age who failed to respond to prior treatments. Eighty-seven percent (27/31) of these patients showed significant responses based on changes in their SALT scores. This case series demonstrates that oral tofacitinib is an effective and safe treatment option for paediatric AA, particularly for children who have failed to respond to traditional treatments or are not suitable for such treatments.

RUN(X) out of blood: emerging RUNX1 functions beyond hematopoiesis and links to Down syndrome

BACKGROUND

RUNX1 is a transcription factor and a master regulator for the specification of the hematopoietic lineage during embryogenesis and postnatal megakaryopoiesis. Mutations and rearrangements on RUNX1 are key drivers of hematological malignancies. In humans, this gene is localized to the 'Down syndrome critical region' of chromosome 21, triplication of which is necessary and sufficient for most phenotypes that characterize Trisomy 21.

MAIN BODY

Individuals with Down syndrome show a higher predisposition to leukemias. Hence, RUNX1 overexpression was initially proposed as a critical player on Down syndrome-associated leukemogenesis. Less is known about the functions of RUNX1 in other tissues and organs, although growing reports show important implications in development or homeostasis of neural tissues, muscle, heart, bone, ovary, or the endothelium, among others. Even less is understood about the consequences on these tissues of RUNX1 gene dosage alterations in the context of Down syndrome. In this review, we summarize the current knowledge on RUNX1 activities outside blood/leukemia, while suggesting for the first time their potential relation to specific Trisomy 21 co-occurring conditions.

CONCLUSION

Our concise review on the emerging RUNX1 roles in different tissues outside the hematopoietic context provides a number of well-funded hypotheses that will open new research avenues toward a better understanding of RUNX1-mediated transcription in health and disease, contributing to novel potential diagnostic and therapeutic strategies for Down syndrome-associated conditions.

Refractory Palmoplantar Pustulosis Successfully Treated with JAK Inhibitor Tofacitinib: A Case Series

Background

Palmoplantar pustulosis (PPP) is a common chronic and recurrent skin disease of the palms and soles with significant pain, mental distress, and functional disability. PPP is challenging to treat and usually requires prolonged management. Therapy resistance and frequent relapse discourages patients from follow-up. No unified standard and no published therapeutic guidelines have yet been defined on PPP treatment. In general, all therapeutic options known for autoimmune diseases, psoriasis in particular, have been tested in PPP. Tofacitinib, an oral JAK inhibitor, has been approved for the treatment of rheumatoid arthritis and shows promise in the treatment of moderate-to-severe plaque psoriasis. However, no clinical trials or case reports have been conducted to confirm the efficacy of tofacitinib in palmoplantar pustulosis.

Methods

Six in total with 6 PPP patient, aged 42-58 years were recruited according to the inclusion and exclusion criteria. Patient characteristics, including triggering factors, concomitant diseases, and previous therapeutic drugs, were investigated. All patients experienced a lack of response to topical drugs and at least one systemic agent. During treatment, visits were scheduled at the start of treatment and at 2, 4, and 12 weeks, and efficacy was assessed using the PPP ASI and PPP PGA.

Results

Our six patients showed an excellent response to tofacitinib as all patients did achieve at least 50% reduction and half of our patients with more than 80% reduction in PPPASI after 4 weeks treatment; at week 12, 5 (83.3%) patients had 80% reduction in PPPASI with no serious adverse events were reported.

Conclusion

The JAK inhibitor tofacitinib is a promising treatment for refractory palmoplantar pustulosis that requires further clinical observation and research.

Sensitive Quantitative In Vivo Assay for Evaluating the Effects of Biomolecules on Hair Growth and Coloring Using Direct Microinjections into Mouse Whisker Follicles

Many people suffer from hair loss and abnormal skin pigmentation, highlighting the need for simple assays to support drug discovery research. Current assays have various limitations, such as being in vitro only, not sensitive enough, or unquantifiable. We took advantage of the bilateral symmetry and large size of mouse whisker follicles to develop a novel in vivo assay called "whisker follicle microinjection assay". In this assay, we plucked mouse whiskers and then injected molecules directly into one side of the whisker follicles using microneedles that were a similar size to the whiskers, and we injected solvent on the other side as a control. Once the whiskers grew out again, we quantitatively measured their length and color intensity to evaluate the effects of the molecules on hair growth and coloring. Several chemicals and proteins were used to test this assay. The chemicals minoxidil and ruxolitinib, as well as the protein RSPO1, promoted hair growth. The effect of the clinical drug minoxidil could be detected at a concentration as low as 0.001%. The chemical deoxyarbutin inhibited melanin production. The protein Nbl1 was identified as a novel hair-growth inhibitor. In conclusion, we successfully established a sensitive and quantitative in vivo assay to evaluate the effects of chemicals and proteins on hair growth and coloring and identified a novel regulator by using this assay. This whisker follicle microinjection assay will be useful when investigating protein functions and when developing drugs to treat hair loss and abnormal skin pigmentation.

JAK inhibitors and black box warnings: what is the future for JAK inhibitors?

INTRODUCTION

Janus kinase inhibitors (JAKi) have dramatically improved the treatment of various autoimmune and myeloproliferative disorders. Recently, concern has arisen regarding their safety in patients with rheumatoid arthritis.

AREAS COVERED

Here, we provide a comprehensive summary of the major current and emerging JAKi and their indications, address recent studies on comparative safety, and provide insight into their future and use. We emphasize that the application of the research findings on a case-by-case basis should consider a patient's age, comorbidities, disease for which JAKi is being considered, disease activity, the JAKi target(s), alternate treatment options available for the patient, and the planned duration of JAKi.

EXPERT OPINION

Rheumatologists are used to prescribing therapies in which a risk-to-benefit assessment is required as well as to screening and monitoring the safety of medications. Thus, rheumatologists are already practiced in applying specific criteria to effectively screen and monitor patients who are candidates for JAKi therapy. Ongoing research will help to clarify any mechanisms underlying differential safety signals between JAK and other therapies, what the balance between risk and efficacy is, who the susceptible subpopulations are, and whether safety signals are shared between different JAKis and across indications.

Clinical and Genetic Aspects of Alopecia Areata: A Cutting Edge Review

Alopecia areata (AA) is a chronic, non-scarring, immune-mediated skin disease that affects approximately 0.5-2% of the global population. The etiology of AA is complex and involves genetic and environmental factors, with significant advancements in genetic research occurring in recent years. In addition to well-known genes such as PTPN22, CTLA4, and IL2, which have been widely supported as being associated with AA, an increasing number of specific gene-related loci have been discovered through advances in genetic research. For instance, gene analysis of microRNAs can reveal the critical role of miRNAs in regulating gene expression, aiding in the understanding of cellular and organismal functional regulatory mechanisms. Furthermore, numerous studies have confirmed the existence of correlations between AA and other immune-related diseases. Examples include hyperthyroidism and rheumatoid arthritis. By understanding the interrelationships between AA and other immune diseases, we can further comprehend potential shared genetic foundations or pathogenic mechanisms among different diseases. Genetic research plays a crucial role in unraveling the pathogenesis of AA, as the identification of genetic variations associated with AA can assist in formulating more effective and targeted treatment strategies.

Baricitinib: A Review in Severe Alopecia Areata

Baricitinib (Olumiant^®), a Janus kinase (JAK) inhibitor, is the first drug approved for the treatment of severe alopecia areata in the USA and the EU. Severe alopecia areata is usually difficult to treat and relapse is common. Patients with this disorder are more likely to suffer from anxiety and depression. In two pivotal placebo-controlled phase 3 clinical trials in adults with severe alopecia areata, oral baricitinib once daily was associated with clinically meaningful scalp, eyebrow, and eyelash hair regrowth over 36 weeks. Baricitinib was generally well tolerated with the most common adverse events being infections, headaches, acne, and elevated levels of creatine phosphokinase. While longer-term data will be necessary to more fully understand the benefits and risks of the drug, currently available data suggest that baricitinib is a useful treatment for patients with severe alopecia areata.

Effect of cyclosporine A - Tempol topical gel for the treatment of alopecia and anti-inflammatory disorders

Over the years, extensive research has been carried out to develop new chemical entities for hair loss treatment. Despite these efforts, the newly developed topical and oral treatments have not proven to be curative. Hair loss can result from underlying mechanisms, such as inflammation and apoptosis around hair follicles. We have developed a nanoemulsion based on Pemulen gel for topical application, tentatively addressing both mechanisms. The novel formulation contains two well-known molecules: Cyclosporin A (CsA), an immunosuppressant calcineurin inhibitor, and Tempol, a potent antioxidant. The in vitro permeation study on human skin revealed that the CsA-Tempol gel formulation effectively delivered CsA into the skin's inner target layer, the dermis. The effects of the CsA-Tempol gel on hair regrowth were further demonstrated in the in vivo well-established androgenetic model induced in female C57BL/6 mice. The beneficial outcome was statistically confirmed by quantitative analysis of hair regrowth, weasured by color density. The results were further supported by histology analysis. Our findings revealed a topical synergy effect, resulting in lower therapeutic concentrations of both actives unlikely to cause systemic side effects. Overall, our research suggests that the CsA-Tempol gel is a highly promising platform for treating alopecia.

Recent Advances in Understanding of the Etiopathogenesis, Diagnosis, and Management of Hair Loss Diseases

Hair-loss diseases comprise heterogenous conditions with respective pathophysiology and clinicopathological characteristics. Major breakthroughs in hair follicle biology and immunology have led to the elucidation of etiopathogenesis of non-scarring alopecia (e.g., alopecia areata, AA) and cicatricial alopecia (e.g., lichen planopilaris, LPP). High-throughput genetic analyses revealed molecular mechanism underlying the disease susceptibility of hair loss conditions, such as androgenetic alopecia (AGA) and female pattern hair loss (FPHL). Hair loss attracted public interest during the COVID-19 pandemic. The knowledge of hair loss diseases is robustly expanding and thus requires timely updates. In this review, the diagnostic and measurement methodologies applied to hair loss diseases are updated. Of note, novel criteria and classification/scoring systems published in the last decade are reviewed, highlighting their advantages over conventional ones. Emerging diagnostic techniques are itemized with clinical pearls enabling efficient utilization. Recent advances in understanding the etiopathogenesis and management for representative hair diseases, namely AGA, FPHL, AA, and major primary cicatricial alopecia, including LPP, are comprehensively summarized, focusing on causative factors, genetic predisposition, new disease entity, and novel therapeutic options. Lastly, the association between COVID-19 and hair loss is discussed to delineate telogen effluvium as the predominating pathomechanism accounting for this sequela.

Platelet lysate promotes hair growth: In vitro and in vivo mechanism and randomized, controlled trial

BACKGROUND

Platelet lysate (PL), a novel platelet derivative, has been widely used in regenerative medicine and is a potential therapy for improving hair growth. It is necessary to fully clarify the potential mechanism and evaluate preliminary clinical effect of PL on hair growth.

METHODS

We used the C57BL/6 model, organ-cultured hair follicles, and RNA-seq analysis to explore the mechanisms of PL regulating hair growth. Then, we performed a randomized, controlled, double-blind study of 107 AGA patients to verify the therapeutic efficacy of PL.

RESULTS

The results confirmed that PL improved hair growth and accelerated hair cycling in mice. Organ-cultured hair follicle evaluation confirmed that PL prolonged anagen remarkably and down-regulated IL-6, C-FOS, and p-STAT5a. Clinically, diameter, hair counts, absolute anagen counts and changes from baseline in the PL group showed a significant improvement at 6 months.

CONCLUSIONS

We elucidated the specific molecular mechanism of PL action on hair growth and proved equal changes in hair follicle performance after PL vs PRP in AGA patients. This study provided novel knowledge of PL, making it ideal for AGA.

Successful treatment of concomitant alopecia universalis and Crohn’s disease with upadacitinib: A case report

Alopecia areata is a non-scarring, autoimmune hair loss disorder that is associated with inflammatory bowel disease. Alopecia areata and inflammatory bowel disease may have a common pathogenic mechanism that involves the Janus kinase/STAT pathway. In addition, there are previous case reports of patients who developed alopecia areata while on biologic therapies for inflammatory bowel disease. JAK1 inhibitors are currently undergoing investigation as potential therapies for Crohn’s disease. Upadacitinib, an oral JAK1 inhibitor, has demonstrated efficacy in treating Crohn’s disease during phase III clinical trials. In this case report, we present a 23-year-old man with Crohn’s disease who previously developed alopecia areata while on adalimumab. He had near-complete resolution of his alopecia universalis after 7 months of treatment with upadacitinib while on concurrent ustekinumab for Crohn’s disease, which he had been taking for 16 months prior to starting upadacitinib. Upadacitinib may be a beneficial therapy for treating concomitant alopecia areata and Crohn’s disease.