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Scarring alopecia, also known as cicatricial alopecia, is a group of hair loss disorders characterized by inflammatory destruction of hair follicles, leading to hair loss and scar tissue formation. Treating scarring alopecia is challenging due to the irreversible damage caused by the inflammatory process. Consequently, early intervention targeting inflammation is crucial for improving prognosis.1 Recently, several reports have emerged supporting the use of platelet-rich plasma (PRP) as a non-conventional therapy for scarring alopecia, suggesting its potential benefits in mitigating inflammation and halting disease progression. While there is a growing body of evidence demonstrating the efficacy and safety of PRP in nonscarring alopecia, such as androgenetic alopecia (AGA) and alopecia areata (AA), there remains a scarcity of evidence regarding the clinical benefits of PRP in scarring alopecias.2-7 In this study, we conducted a literature review exploring the effectiveness and safety of PRP in treating scarring alopecia. Eleven studies describing PRP treatment outcomes were identified. Overall, PRP demonstrated a positive impact, slowing disease progression with reduced signs of inflammation and no reported adverse effects. However, it is important to note that the evidence supporting the utility of PRP in scarring alopecias is currently limited to case reports. Therefore, immunomodulatory therapies should remain the mainstay therapy for scarring alopecias until further investigations are warranted. J Drugs Dermatol. 2024;23(12):1076-1082. doi:10.36849/JDD.7813.

Human prenatal skin is populated by innate immune cells, including macrophages, but whether they act solely in immunity or have additional functions in morphogenesis is unclear. Here we assembled a comprehensive multi-omics reference atlas of prenatal human skin (7-17 post-conception weeks), combining single-cell and spatial transcriptomics data, to characterize the microanatomical tissue niches of the skin. This atlas revealed that crosstalk between non-immune and immune cells underpins the formation of hair follicles, is implicated in scarless wound healing and is crucial for skin angiogenesis. We systematically compared a hair-bearing skin organoid (SkO) model derived from human embryonic stem cells and induced pluripotent stem cells to prenatal and adult skin1. The SkO model closely recapitulated in vivo skin epidermal and dermal cell types during hair follicle development and expression of genes implicated in the pathogenesis of genetic hair and skin disorders. However, the SkO model lacked immune cells and had markedly reduced endothelial cell heterogeneity and quantity. Our in vivo prenatal skin cell atlas indicated that macrophages and macrophage-derived growth factors have a role in driving endothelial development. Indeed, vascular network remodelling was enhanced following transfer of autologous macrophages derived from induced pluripotent stem cells into SkO cultures. Innate immune cells are therefore key players in skin morphogenesis beyond their conventional role in immunity, a function they achieve through crosstalk with non-immune cells.

We previously showed that inhibition of glycolysis in cutaneous squamous cell carcinoma (SCC)-initiating cells had no effect on tumorigenesis, despite the perceived requirement of the Warburg effect, which was thought to drive carcinogenesis. Instead, these SCCs were metabolically flexible and sustained growth through glutaminolysis, another metabolic process frequently implicated to fuel tumorigenesis in various cancers. Here, we focused on glutaminolysis and genetically blocked this process through glutaminase (GLS) deletion in SCC cells of origin. Genetic deletion of GLS had little effect on tumorigenesis due to the up-regulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We went on to show that posttranscriptional regulation of nutrient transporters appears to mediate metabolic flexibility in this SCC model. To define the limits of this flexibility, we genetically blocked both glycolysis and glutaminolysis simultaneously and found the abrogation of both of these carbon utilization pathways was enough to prevent both papilloma and frank carcinoma.

Renowned for its invaluable undercoat, the cashmere goat is well known. The growth of cashmere fibre initiates when the relatively inactive telogen stage transitions to the anagen stage, which involves active proliferation. However, the molecular mechanisms responsible for this process are still unclear. Here, SWATH mass spectrometry (MS), a comparative proteomic analysis, was conducted to examine the proteomic alterations in Inner Mongolia cashmere goat skin samples at two different developmental stages (anagen and telogen). In total, 2414 proteins were detected, with 631 proteins showing differential regulation (503 upregulated proteins and 128 downregulated proteins). Bioinformatic analysis revealed that these proteins, which are differentially regulated, play crucial roles in the pathways associated with metabolism and fatty acids according to the GO and KEGG analyses. Furthermore, interactome analysis revealed that differentially regulated keratins have a crucial impact. The localization of KRT25, KRT71, and KRT82 using immunohistochemistry revealed that these proteins were expressed in the secondary hair follicles of cashmere goat skin. The keratin family plays an irreplaceable and important role in the process of hair follicle growth. [ABSTRACT FROM AUTHOR]

Hair follicles are essential appendages of human skin that function in protection, sensation, thermoregulation and social interactions. The multicellular components, particularly the dermal papilla, matrix and bulge housing stem cells, enable cyclic hair growth postnatally. However, miniaturization and loss of hair follicles can occur in the context of ageing, trauma and various alopecia-related diseases. Conventional treatments involve the redistribution of existing follicles, which may not be viable in patients lacking follicular resources. Recent progress in the comprehension of morphogenesis and the development of biomaterials has significantly advanced follicle reconstruction, incorporating organ germ assembling, stem cell induction and bioprinting techniques. Despite these advancements, fully restoring hair follicles remains challenging due to the complexities of replicating embryonic signals and sustaining growth cycles. Identifying suitable cell sources for clinical applications also presents a hurdle. Here, we retrospect the progress made in the field of hair follicle regeneration, aiming to offer an exhaustive analysis on the benefits and limitations of these methods, and to foster the development of innovative solutions. [ABSTRACT FROM AUTHOR]

Cyclodextrin metal-organic frameworks (CD-MOF) as delivery carriers have gained great attention in the biomedical field. However, limited by challenges of moisture-sensitive nature, the design and application of CD-MOF-based hair follicle delivery for androgenic alopecia (AGA) has rarely been explored. We developed the metal-organic frameworks as hair follicle-targeted delivery system (SA-MOF), stearic acid (SA) was used to modify metal-organic frameworks to form a protective hydrophobic layer on the surface and provide the additional hair growth-promoting effect. Cardamonin (CAR), a newly discovered biosafety natural product, was encapsulated in SA-MOF (CAR@SA-MOF) to promote the therapeutic efficacy on AGA. CD-MOF surface-engineered nanoparticles modified by SA avoided the rapid hydration and disintegration of CD-MOF in water, which improved the drug release and follicular deposition of drug. Assisted by the delivery of SA-modified CD-MOF carriers, the drug significantly promoted cell proliferation and migration, achieving the promoting effect on hair follicle differentiation and hair regeneration in testosterone-challenged C57BL/6 mice. Simultaneously, SA modification provided additional promoting effects on human dermal papilla cell proliferation, regulating effect on keratinocyte growth factor, and activating effect of key signaling pathways. The surface engineering design of CD-MOF hair follicle drug delivery based on SA modification exhibits significant potential for the treatment of hair follicle and sebaceous gland-related diseases. Highlights: Cyclodextrin metal-organic frameworks (CD-MOF) surface-engineered nanoparticles (CAR@SA-MOF) modified by stearic acid (SA) exhibited a promotion effect on hair growth and could be used as a new therapeutic strategy for androgenetic alopecia. SA-modification avoids the rapid hydration and disintegration of CD-MOF in water, which provides a new strategy for the sustained long-acting release of drugs in the skin and hair follicles. SA-modified cyclodextrin metal-organic frameworks could increase hair follicle delivery and accumulation under the ratchet effect. The therapeutic mechanisms of CAR@SA-MOF on androgenetic alopecia involve regulation of growth factors and activation of Wnt/β-catenin, AKT/ERK, and SHH/Gli signaling pathways. SA-modification provided additional promoting effect on human dermal papilla cell proliferation, regulating effect on keratinocyte growth factor, and activating effect of key signaling pathways. [ABSTRACT FROM AUTHOR]

This study developed a three-dimensional ultrastructural analysis application using serial block-face scanning electron microscopy (SBF-SEM) to investigate surgically acquired human skin tissues containing the arrector pili muscle. We utilized the en bloc staining, including reduced osmium, thiocarbohydrazide, and lead aspartate, as well as the embedding using a carbon-based conductive resin. Next, we obtained serial images with SBF-SEM. The results revealed dense nerve fiber networks branching from nearby nerve fiber bundles outside the muscle and running among muscle fibers. Additionally, the dense nerve network running through and along arrector pili muscle fibers rarely penetrates the connective tissues between smooth muscle fibers and epithelial cells. Furthermore, in the observation area, no individual smooth muscle fibers formed adhesion structures with the epithelial cells of the hair follicle, ending in the dermal extracellular matrix near the epithelial cells. These results indicate the usefulness of this approach for three-dimensional ultrastructural analyses of human skin tissues comprising follicular units and revealing structural changes in skin tissues, especially the arrector pili muscle and nerve fibers with hair follicular epithelium, in aging and diseased conditions. [ABSTRACT FROM AUTHOR]

Hair loss has long been a significant concern for many individuals. Recent studies have indicated that mitochondria play a more crucial role in hair loss than previously recognized. This review summarizes the connection between mitochondrial dysfunction and hair follicle development, outlines the links between diseases related to mitochondrial disorders and hair issues, and highlights the influence of mitochondrial dysfunction on androgenetic alopecia. We discuss the cellular and signaling mechanisms associated with hair loss and examine how mitochondrial dysfunction, such as insufficient energy supply, signaling irregularities, protein/gene abnormalities, and programmed cell death, can hinder the normal proliferation, differentiation, and growth of hair follicle cells. Furthermore, we discuss current treatment approaches and potential innovative therapies, including mitochondrion-targeting drugs and advanced techniques that directly target hair follicle cells, providing fresh insights into the crucial role of mitochondria in maintaining hair follicle health and managing hair disorders. Furthermore, this review explores future therapeutic strategies and proposes that mitochondrial research could lead to groundbreaking treatments for hair loss, thus providing optimism and new avenues for the treatment of individuals experiencing hair loss. This review not only underscores the central importance of mitochondria in hair health but also emphasizes the importance of advancing research and treatment in this field. [ABSTRACT FROM AUTHOR]

Background: Rex rabbit is famous for its silky and soft fur coat, a characteristic predominantly attributed to its hair follicles. Numerous studies have confirmed the crucial roles of mRNAs and non-coding RNAs (ncRNAs) in regulating key cellular processes such as cell proliferation, differentiation, apoptosis and immunity. However, their involvement in the regulation of the hair cycle in Rex rabbits remains unknown. Results: In this study, we identified the hair follicle stages of Rex rabbits aged 3 to 5.5 months. Skin samples collected at 4, 5 and 5.5 months, representing the morphological features of the anagen, catagen and telogen stage separately, were finally selected for whole-transcriptome analysis. 25,736 mRNA, 8280 lncRNA, 24,885 circRNA and 1138 miRNA transcripts were identified. 6027 differently expressed mRNAs (DEGs), 2381 differently expressed lncRNAs (DELs), 438 differently expressed circRNAs (DECs) and 167 differently expressed miRNAs (DEMs) were detected in the anagen vs. catagen (AvC) comparison. 4092 DEGs, 1540 DELs, 356 DECs and 141 DEMs were detected in the anagen vs. telogen (AvT) comparison. 2290 DEGs, 779 DELs, 249 DECs and 92 DEMs were detected in the catagen vs. telogen (CvT) comparison. DEGs were primarily enriched in GO items including plasma membrane, integral component of plasma membrane and extracellular space. KEGG enrichment analysis revealed that DEGs were mainly enriched in PI3K-Akt signaling pathway, cell cycle and Wnt signaling pathway (p < 0.05). KEGG analysis showed trans-acting genes of DELs were significantly enriched in Hippo signaling pathway, PI3K-Akt signaling pathway and Melanogenesis. Target genes of DEMs were mainly enriched in MAPK signaling pathway, Wnt signaling pathway, ECM-receptor interaction and Signaling pathways regulating pluripotency of stem cells. Based on the ceRNA mechanism, lncRNA/circRNA-miRNA-mRNA networks were constructed involving 9 DECs, 437 DELs, 50 DEMs and 416 DEGs. Conclusions: Totally, this study provides comprehensive insights into the expression patterns of protein-coding genes and non-coding transcripts throughout the HF cycle, and enhancing the understanding of the regulatory mechanisms underlying mammalian hair fiber development. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Hair graying is one of the most intuitive phenotypes of human aging. Although the specific role of genetic factors in gray hair is still uncertain, studies have found that oxidative stress, emotional stress, neuroendocrine regulation, diseases, and trace elements contained in the body may all be related to the generation of white hair. Melanin production in hair follicles is strictly coupled to the nascent stage of the hair growth cycle. Melanin stem cell self-maintenance defects and melanocyte synthesis disorders under the regulation of various hormones and biological factors in the process of pigment synthesis may be the key to the generation of white hair. This article reviews the recent research on the mechanism of white hair formation and the future prospects for the prevention and treatment of white hair from different aspects. [ABSTRACT FROM AUTHOR]

Simple Summary: Semi-natural pastures provide the primary food source for sheep, whose grazing activity contributes to preserving grassland biodiversity. However, summer drought stress reduces the nutritional value of pastures, with negative consequences on the morpho-functional characteristics of the digestive system and other sheep systems. Understanding the molecules linked to energy metabolism is important for identifying suitable markers of tissue functionality and ensuring animal well-being, a key factor in sustainable livestock production. Ghrelin plays a role in food intake and is involved in tissue regeneration, repair and diseases at the skin level, even if information about this organ is very scarce. This study aims to analyze the ghrelin system in the skin of sheep grazing on seminatural pasture during the spring–summer season and compare differently fed animals. The results indicate that ghrelin and its receptor are localized in sheep skin appendices, with greater expression in animals fed with diet supplementation. This finding suggests that diet may influence the proliferative activity of the hair follicle through variations in the ghrelin system expression. These insights could be a useful tool for the breeders to counteract the negative effects of increasing summer aridity. Ghrelin (GhRL) is an orexigenic hormone influenced by nutritional state. It plays a role in skin repair and diseases, though little information exists regarding its function in this organ. GhRL and its receptor were investigated in the skin of sheep under different feeding conditions to explore GhRL system presence and possible modifications due to diet. Three-year-old female sheep were free to graze from June to the pasture maximum flowering (MxF group) and from this period to maximum dryness addicted (Exp group) or not (MxD group) with 600 gr/die/head of barley and corn. Skin samples were processed for immunohistochemistry and real-time PCR. The immunostaining showed the presence of the GhRL system in skin appendages. Indeed, the ligand was localized in the hair follicles whereas the receptor was also observed in sweat glands and smooth muscle cells. The expression of both genes was significantly higher in the Exp group (3.6 and 2.9 folds respectively, p < 0.05) compared with the MxF group. These results suggest that the GhRL system is involved in the regulation of hair follicles and sweat glands. In addition, diet supplementation may positively modulate the expression of GhRL and its receptor in the skin. [ABSTRACT FROM AUTHOR]

Abstract Wool growth and fineness regulation is influenced by some factors such as genetics and environment. At the same time, lncRNA participates in numerous biological processes in animal production. In this research, we conducted a thorough analysis and characterization of the microstructure of wool, along with long non-coding RNAs (lncRNAs), their target genes, associated pathways, and Gene Ontology terms pertinent to the wool fineness development. The investigation utilized scanning electron microscopy and transcriptomic technology, focusing on two distinct types in Gansu alpine fine-wool sheep: coarse type (group C, MFD = 22.26 ± 0.69 μm, n = 6) and fine type (group F, MFD = 16.91 ± 0.29 μm, n = 6), which exhibit differing wool fiber diameters. The results showed that fine type wool fiber scales were more regularly distributed in rings with large scale spacing and smooth edges, while coarse type wool fiber scales were more irregularly arranged in tiles with relatively rougher edges, and the density of wool scales was greater than that of fine type wool. Furthermore, a comprehensive analysis revealed 164 differentially expressed lncRNAs along with 146 potential target genes linked to these lncRNAs in the skin tissues from groups C and F. Utilizing functional enrichment analysis on the target genes, we successfully identified a number of target genes might be associated with the improvement of wool fineness, such as FOXN1, LIPK, LOC101116068, LOC101106296, KRTAP5.4, KRT71, KRT82, DNASE1L2, which are related to hair follicle development, histidine metabolism, epidermal cell differentiation, oxidative phosphorylation and hair cycle process. Additionally, the interoperability network involving lncRNAs-mRNAs indicated lncRNAs (MSTRG.17445.2, XR_006060725.1, MSTRG.871.1, MSTRG.10907.4) might play a significant role in the wool growth development and fineness improvement process. In conclusion, the research enlarges the current lncRNAs database, providing a new insight for the investigation of wool fineness development in fine-wool sheep.

Immune tolerance is maintained in lymphoid organs (LOs). Despite the presence of complex immune cell networks in non-LOs, it is unknown whether self-tolerance is maintained in these tissues. We developed a technique to restrict genetic recombination to regulatory T cells (Tregs) only in skin. Selective depletion of skin Tregs resulted in T cell-mediated inflammation of hair follicles (HFs). Suppression did not rely on CTLA-4, but instead on high-affinity interleukin-2 (IL-2) receptor expression by skin Tregs, functioning exclusively in a cell-extrinsic manner. In a novel model of HF stem cell (HFSC)-driven autoimmunity, we reveal that skin Tregs immunologically protect the HFSC niche. Finally, we used spatial transcriptomics to identify aberrant IL-2 signaling at stromal-HF interfaces in a rare form of human alopecia characterized by HFSC destruction and alopecia areata. Collectively, these results reveal the fundamental biology of Tregs in skin uncoupled from the systemic pool and elucidate a mechanism of self-tolerance.

Hair follicle stem cells (HFSCs) and dermal papilla cells (DPCs) are crucial in the biogenesis and maintenance of hair follicles (HFs). This study demonstrated that a fragment derived from aminoacyl-tRNA synthetase-interacting multifunctional protein1 (AIMP1) secreted from HFSCs activated DPCs and maintained HF homeostasis. A histological analysis revealed that AIMP1 levels in HF decreased with hair loss. Hair regrowth in AIMP1-induced mice was faster than in non-induced mice. Deletion mapping revealed 41 amino acids (TN41, aa 6-46) as the active region of AIMP1. The N-terminal peptide fragment of AIMP1 generated by MMP1 was secreted from Wnt-treated HFSCs to activate DPCs. TN41 activated Akt and ERK, increased β-catenin, and enhanced DPC activation. TN41 promoted hair shaft elongation in cultured human HFs and improved the hair-inducing activity of cultured DPC spheroids. Our findings suggest that the AIMP1 fragment secreted from HFSCs stimulates active hair regrowth through activating DPCs.

Abstract Background Dorper sheep are celebrated for their fast maturation and superior meat quality, with some shedding their wool each spring. Wool shedding occurs naturally due to the hair follicle (HF) cycle, but its regulatory mechanisms remain unclear and need further investigation. Results In this study, shedding and non-shedding sheep were selected from the same Dorper flock. Skin samples were collected in September of the first year and January and March of the following years. RNA sequencing was performed on these samples. Principal component analysis (PCA) was used to assess the results. A total of 2536 differentially expressed genes (DEGs) were identified. Using a clustering heatmap and fuzzy clustering analysis three distinct gene expression patterns were identified: A pattern (high expression in anagen), T1 pattern, and T2 pattern (high expression in telogen). For each pattern, differentially expressed genes (DEGs) were analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Combining this with pathway expression analysis, six A-pattern and fourteen T-pattern pathways linked to telogen-anagen transition in the HF cycle were identified. Networks of key pathways were then constructed. Additionally, key genes were identified in the telogen-anagen transition, including one A-pattern gene and seven T-pattern (T1, 1; T2, 6) genes, using the Maximal Clique Centrality (MCC) tool in Cytoscape. Predicted transcription factors (TFs) involved in key pathways, such as LEF and STAT5B, were identified. Finally, RNA-seq results were confirmed by RT-qPCR. Conclusion This study highlights critical genes and pathways in the telogen-anagen transition, and transcriptome sequencing along with bioinformatics analysis provides new insights into the regulatory mechanisms of the HF cycle and development.

Abstract The hair follicle stem cell niche is an immune-privileged microenvironment, characterized by reduced antigen presentation, thus shielding against permanent immune-mediated tissue damage. In this study, we demonstrated the protective role of hair follicle-specific epidermal growth factor receptor (EGFR) against scarring hair follicle destruction. Mechanistically, disruption of EGFR signaling generated a cell-intrinsic hypersensitivity within the JAK-STAT1 pathway, which, synergistically with interferon gamma expressing CD8 T-cell and NK-cell-mediated inflammation, compromised the stem cell niche. Hair follicle-specific genetic depletion of either JAK1/2 or STAT1 or therapeutic inhibition of JAK1/2 ameliorated the inflammation, restored skin barrier function and activated the residual stem cells to resume hair growth in mouse models of epidermal and hair follicle-specific EGFR deletion. Skin biopsies from EGFR inhibitor-treated and cicatricial alopecia patients revealed an active JAK-STAT1 signaling signature along with upregulation of antigen presentation and downregulation of key components of the EGFR pathway. Our findings offer molecular insights and highlight a mechanism-based therapeutic strategy for addressing chronic folliculitis associated with EGFR-inhibitor anti-cancer therapy and cicatricial alopecia.

In order to promote the development of hair transplantation, particularly the establishment of standards, the Hair Transplantation Expert Group of Plastic and Aesthetic National Medical Quality Control Center invited experts in the field of hair transplantation across China and formed a draft of the Expert Consensus on Standard Terminology for Hair Transplantation based on the collation of relevant literature and monographs. By combining Delphi methodology and consensus meetings, the expert group conducted several rounds of consultations on issues such as follicular unit anatomy, harvesting, dissection, and implantation, ultimately presenting 54 terminologies. This consensus considers the original Chinese and English meanings as well as the professional characteristics of terms used in hair transplantation, highlights the unique features and advantages of hair transplantation, and preserves its essence while promoting innovation, with the hope of providing valuable reference for clinical researchers engaged in hair transplantation both domestically and internationally, and better facilitating the standardization and advancement of the field.

Abstract Background The incidence of androgenetic alopecia in males is on the rise annually, with hair transplantation using follicular unit extraction (FUE) gaining increasing acceptance as an appropriate treatment for these individuals. Methods A retrospective study was undertaken, involving 158 male patients diagnosed with androgenetic alopecia, who underwent treatment between January 2016 and December 2020 at the Medical Cosmetology Department of the First Affiliated Hospital of Xi’an Medical University. Demographic data and treatment characteristics were documented and analyzed. Clinical efficacy, operation-related complications, patient satisfaction rates, and quality of life scores were assessed and analyzed. Results Following FUE hair transplantation, over 90% of the hair follicles survived in 158 patients, with more than 85% of patients achieving a hair follicle survival rate exceeding 95% at 12 months post-operation. Patient satisfaction rates exceeded 98%, while the complication rate was below 6%. Conclusion Our findings demonstrate that FUE is a minimally invasive hair transplant technique associated with a high hair follicle survival rate and optimal hair density. This approach proves effective in treating male androgenetic alopecia and merits further clinical application.

Abstract Background Hair follicles (HFs) are dynamic structures which are readily accessible within the skin that contain various pools of stem cells with broad regenerative potential, such as dermal papilla cells (DPCs), dermal sheath cells, and epithelial HF stem cells. DPCs act as signalling centres for HF regeneration. The current method for isolating human DPCs are inefficient. These methods struggle to obtain freshly isolated original DPCs and do not maintain the characteristics of DPCs effectively. Methods In this study, two simple but more efficient methods were explored. Force-triggered density gradient sedimentation (FDGS) and cocktail enzyme digestion treatment (CEDT) were used to isolate purified DP spheres from human HFs, obtaining purified freshly isolated original DPCs from DP spheres. The expression profiles of isolated DPCs were tested, and gene expression of DPC-specific markers were analyzed using immunofluorescence staining, RT-qPCR and western blot. Results The 10% Ficoll PM400 was determined as the optimal concentration for FDGS method. Primary DPCs, DSCs and HFSCs were isolated simultaneously using the FDGS and CEDT method. The expression profiles of fresh DPCs isolated using the FDGS and CEDT methods were similar to those of traditionally isolated DPCs. DP-specific markers were expressed at significantly higher levels in freshly isolated DPCs than in traditionally isolated DPCs. Conclusions Compared to traditional methods, the presented laboratory protocols were able to isolate fresh DPCs with high efficiency, thereby improving their research potential.

Abstract Oxytocin has various effects ranging from promoting labor in pregnant women to alleviating stress. Recently, we reported the hair growth-promoting effects of oxytocin in hair follicle organoids. However, its clinical application faces challenges such as rapid degradation in vivo and poor permeability due to its large molecular weight. Therefore, in this study, we investigated the effects of the oxytocin receptor (OXTR) agonists WAY267464 and LIT001 as alternatives to oxytocin on hair growth. Human dermal papilla (DP) cells were cultured in WAY267464 or LIT001-supplemented medium. The addition of WAY267464 and LIT001 increased the expression of hair growth-related genes in DP cells. We tested the hair growth-promoting effects of WAY267464 and LIT001 using hair follicle organoids in vitro and found that they significantly promoted hair follicle sprouting. Thus, our findings indicate that WAY267464 and LIT001 are potential hair growth agents and may encourage further research on the development of novel hair growth agents targeting OXTR in patients with alopecia.

The bending of simple cellular sheets into complex three-dimensional (3D) forms requires developmental patterning cues to specify where deformations occur, but how positional information directs morphological change is poorly understood. Here, we investigate how morphogen signaling and cell fate diversification contribute to the morphogenesis of murine hair placodes, in which collective cell movements transform radially symmetric primordia into bilaterally symmetric tubes. Through live imaging and 3D volumetric reconstructions, we demonstrate that Wnt and Shh establish radial patterns of cell fate, cell morphology, and movement within developing placodes. Cell fate diversity at different radial positions provides unique and essential contributions to placode morphogenesis. Further, we show that downstream of radial patterning, gradients of classical cadherin expression are required for efficient epithelial rearrangements. Given that the transformation of epithelial discs into 3D tubes is a common morphological motif used to shape diverse organ primordia, mechanisms of radially patterned morphogenesis are likely highly conserved across evolution. [Display omitted] • Cell fates within hair follicle primordia emerge in a radial pattern • Wnt gradients and Shh radially pattern cell fate, shape, adhesion, and motility • Radial position and fate determine cell morphology and morphogenetic behavior • Radial adhesion gradients promote cell rearrangements, driving placode polarization Leybova et al. utilize live imaging and 3D reconstructions to uncover a radial pattern of cell fate, morphology, adhesion, and motility in developing hair follicle primordia. Radial patterning is established by graded Wnt signaling and Shh and is necessary for the complex morphogenetic changes that drive placode budding and polarization. [ABSTRACT FROM AUTHOR]

Background: Dorper sheep are celebrated for their fast maturation and superior meat quality, with some shedding their wool each spring. Wool shedding occurs naturally due to the hair follicle (HF) cycle, but its regulatory mechanisms remain unclear and need further investigation. Results: In this study, shedding and non-shedding sheep were selected from the same Dorper flock. Skin samples were collected in September of the first year and January and March of the following years. RNA sequencing was performed on these samples. Principal component analysis (PCA) was used to assess the results. A total of 2536 differentially expressed genes (DEGs) were identified. Using a clustering heatmap and fuzzy clustering analysis three distinct gene expression patterns were identified: A pattern (high expression in anagen), T1 pattern, and T2 pattern (high expression in telogen). For each pattern, differentially expressed genes (DEGs) were analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Combining this with pathway expression analysis, six A-pattern and fourteen T-pattern pathways linked to telogen-anagen transition in the HF cycle were identified. Networks of key pathways were then constructed. Additionally, key genes were identified in the telogen-anagen transition, including one A-pattern gene and seven T-pattern (T1, 1; T2, 6) genes, using the Maximal Clique Centrality (MCC) tool in Cytoscape. Predicted transcription factors (TFs) involved in key pathways, such as LEF and STAT5B, were identified. Finally, RNA-seq results were confirmed by RT-qPCR. Conclusion: This study highlights critical genes and pathways in the telogen-anagen transition, and transcriptome sequencing along with bioinformatics analysis provides new insights into the regulatory mechanisms of the HF cycle and development. [ABSTRACT FROM AUTHOR]

The hair follicle stem cell niche is an immune-privileged microenvironment, characterized by reduced antigen presentation, thus shielding against permanent immune-mediated tissue damage. In this study, we demonstrated the protective role of hair follicle-specific epidermal growth factor receptor (EGFR) against scarring hair follicle destruction. Mechanistically, disruption of EGFR signaling generated a cell-intrinsic hypersensitivity within the JAK-STAT1 pathway, which, synergistically with interferon gamma expressing CD8 T-cell and NK-cell-mediated inflammation, compromised the stem cell niche. Hair follicle-specific genetic depletion of either JAK1/2 or STAT1 or therapeutic inhibition of JAK1/2 ameliorated the inflammation, restored skin barrier function and activated the residual stem cells to resume hair growth in mouse models of epidermal and hair follicle-specific EGFR deletion. Skin biopsies from EGFR inhibitor-treated and cicatricial alopecia patients revealed an active JAK-STAT1 signaling signature along with upregulation of antigen presentation and downregulation of key components of the EGFR pathway. Our findings offer molecular insights and highlight a mechanism-based therapeutic strategy for addressing chronic folliculitis associated with EGFR-inhibitor anti-cancer therapy and cicatricial alopecia. Synopsis: Defective EGFR signaling induces hypersensitive JAK-STAT1 pathway in the hair follicle. This results in the collapse of the stem cell niche during microbial skin inflammation and the scarring of the hair follicle. JAK inhibition therefore offers a therapeutic option to counteract scarring alopecia. Chronic microbial folliculitis associated with EGFR deficiency initiates hallmarks of scarring alopecia. Cell intrinsic JAK1/2-STAT1 signaling drives hair follicle destruction. CD8 T-cells and NK-cells expressing IFNγ trigger the JAK-STAT1 cascade. Therapeutic JAK1/2 inhibition alleviates skin inflammation, restores barrier integrity and leads to hair regrowth. Defective EGFR signaling induces hypersensitive JAK-STAT1 pathway in the hair follicle. This results in the collapse of the stem cell niche during microbial skin inflammation and the scarring of the hair follicle. JAK inhibition therefore offers a therapeutic option to counteract scarring alopecia. [ABSTRACT FROM AUTHOR]

Ectodermal organs, such as hair follicles, originate from simple epithelial and mesenchymal sheets through a complex developmental process driven by interactions between these cell types. This process involves dermal condensation, placode formation, bud morphogenesis, and organogenesis, and all of these processes require intricate interactions among various tissues. Recent research has emphasized the crucial role of reciprocal and dynamic interactions between cells and the extracellular matrix (ECM), referred to as the "dynamic duo", in the development of ectodermal organs. These interactions provide spatially and temporally changing biophysical and biochemical cues within tissues. Using the hair follicle as an example, this review highlights two types of cell–ECM adhesion units—focal adhesion-type and hemidesmosome-type adhesion units—that facilitate communication between epithelial and mesenchymal cells. This review further explores how these adhesion units, along with other cell–ECM interactions, evolve during hair follicle development and regeneration, underscoring their importance in guiding both developmental and regenerative processes. [Display omitted] • Dynamic cell-ECM interactions guide hair follicle development and regeneration. • Focal adhesions and hemidesmosomes are key ECM adhesion units in hair follicles. • Basement membrane mediates epithelial and mesenchymal mechanochemical interactions. [ABSTRACT FROM AUTHOR]

Senescent cells secrete a senescence‐associated secretory phenotype (SASP), which can induce senescence in neighboring cells. Human dermal papilla (DP) cells lose their original hair inductive properties when expanded in vitro, and rapidly accumulate senescent cells in culture. Protein and RNA‐seq analysis revealed an accumulation of DP‐specific SASP factors including IL‐6, IL‐8, MCP‐1, and TIMP‐2. We found that combined senolytic treatment of dasatinib and quercetin depleted senescent cells, and reversed SASP accumulation and SASP‐mediated repressive interactions in human DP culture, resulting in an increased Wnt‐active cell population. In hair reconstitution assays, senolytic‐depleted DP cells exhibited restored hair inductive properties by regenerating de novo hair follicles (HFs) compared to untreated DP cells. In 3D skin constructs, senolytic‐depleted DP cells enhanced inductive potential and hair lineage specific differentiation of keratinocytes. These data revealed that senolytic treatment of cultured human DP cells markedly increased their inductive potency in HF regeneration, providing a new rationale for clinical applications of senolytic treatment in combination with cell‐based therapies. [ABSTRACT FROM AUTHOR]

Background: Glucocorticoids and androgens in the hair follicle have been of interest for many years, particularly cortisol and cortisone in retrospective studies associated with chronic stress and Cushing's syndrome. No studies have reported aldosterone or 18-hydroxycorticosterone in the adrenal mineralocorticoid panel in the hair follicle. This study aimed to identify potential biomarkers in endocrine conditions associated with steroid excess or deficiency using a novel extraction protocol in the analysis of mineralocorticoids and glucocorticoids in the hair follicle. Methods and findings: Hair was collected from 15 healthy male and female volunteers. Segments that were cut along the length of long, medium, and short hair and segments shaved on the scalp and the cheek were prepared for analysis. Hair samples were extracted using an automated accelerated solvent extraction (ASE) system. Steroids were analyzed using high-throughput ultra-performance convergence chromatography–tandem mass spectrometry. All mineralocorticoids and glucocorticoids were detected above the lower limit of quantification and none of the steroids differed statistically comparing male and female concentrations. Deoxycortisol, deoxycorticosterone, and aldosterone were detected for the first time in men. In both genders, 18-hydroxycortisosterone was detected for the first time. The median concentrations for women and men, respectively, were as follows: deoxycortisol, 14.2 and 19.2 pg/mg; cortisol, 34.7 and 33.9 pg/mg; cortisone, 22.4 and 22.0 pg/mg; deoxycorticosterone, 83.0 and 50.2 pg/mg; corticosterone, 10.9 and 11.5 pg/mg; 18-hydroxycorticosterone, 24.8 and 24.8 pg/mg; and aldosterone, 23.4 and 22.7 pg/mg. Deoxycortisol and deoxycorticosterone showed marked fluctuation along the hair follicle in both genders and showed inter-individual variance. Conversely, cortisol, cortisone, corticosterone, 18-hydroxycortisosterone, and aldosterone did not fluctuate, with no inter-individual variance. Cortisol was 1.5-fold higher than cortisone in accordance with the circulatory cortisol/cortisone relationship. Conclusions: The novel extraction method optimized steroid measurement, showing the consistency of measurement for glucocorticoids, cortisol and cortisone, and mineralocorticoids, corticosterone, 18-hydroxycorticosterone, and aldosterone. Data suggest these steroids in the hair follicle to be ideal biomarkers in improving diagnostic testing, investigating conditions of steroid excess or deficiency in hypoaldosteronism, primary hyperaldosteronism, Cushing's syndrome, and the congenital adrenal hyperplasia subtypes. [ABSTRACT FROM AUTHOR]

Hair is an intricate biological structure that originates from hair follicles (HFs), which are complex mini‐organs embedded in the skin. Each HF undergoes continuous cycles of growth (anagen), regression (catagen), and rest (telogen), driven by intricate signaling pathways and interactions between epithelial and mesodermal cells. The development of HFs requires the interplay of several key signaling pathways, including Wnt, Shh, Notch, and BMP. The Wnt pathway is primarily involved in induction, Shh is essential for early organogenesis and later stages of cytodifferentiation, Notch signaling governs the fate of HF stem cells, and BMP plays a role in cytodifferentiation. Hair health is closely associated with psychological well‐being and personal distress. While hair loss (alopecia) does not impact biological health, it significantly affects social well‐being. Therefore, a deep understanding of the molecular mechanisms underlying HF development is crucial for developing treatments for hair‐related problems and improving hair health. This knowledge has led to significant advancements in therapeutic applications, particularly in treating hair loss disorders, enhancing wound healing, and developing cosmetic treatments. This paper aims to review the molecular mechanisms involved in HF development, with an emphasis on their potential impact on human health and well‐being. [ABSTRACT FROM AUTHOR]

Background: The incidence of androgenetic alopecia in males is on the rise annually, with hair transplantation using follicular unit extraction (FUE) gaining increasing acceptance as an appropriate treatment for these individuals. Methods: A retrospective study was undertaken, involving 158 male patients diagnosed with androgenetic alopecia, who underwent treatment between January 2016 and December 2020 at the Medical Cosmetology Department of the First Affiliated Hospital of Xi'an Medical University. Demographic data and treatment characteristics were documented and analyzed. Clinical efficacy, operation-related complications, patient satisfaction rates, and quality of life scores were assessed and analyzed. Results: Following FUE hair transplantation, over 90% of the hair follicles survived in 158 patients, with more than 85% of patients achieving a hair follicle survival rate exceeding 95% at 12 months post-operation. Patient satisfaction rates exceeded 98%, while the complication rate was below 6%. Conclusion: Our findings demonstrate that FUE is a minimally invasive hair transplant technique associated with a high hair follicle survival rate and optimal hair density. This approach proves effective in treating male androgenetic alopecia and merits further clinical application. [ABSTRACT FROM AUTHOR]

Background: Hair follicles (HFs) are dynamic structures which are readily accessible within the skin that contain various pools of stem cells with broad regenerative potential, such as dermal papilla cells (DPCs), dermal sheath cells, and epithelial HF stem cells. DPCs act as signalling centres for HF regeneration. The current method for isolating human DPCs are inefficient. These methods struggle to obtain freshly isolated original DPCs and do not maintain the characteristics of DPCs effectively. Methods: In this study, two simple but more efficient methods were explored. Force-triggered density gradient sedimentation (FDGS) and cocktail enzyme digestion treatment (CEDT) were used to isolate purified DP spheres from human HFs, obtaining purified freshly isolated original DPCs from DP spheres. The expression profiles of isolated DPCs were tested, and gene expression of DPC-specific markers were analyzed using immunofluorescence staining, RT-qPCR and western blot. Results: The 10% Ficoll PM400 was determined as the optimal concentration for FDGS method. Primary DPCs, DSCs and HFSCs were isolated simultaneously using the FDGS and CEDT method. The expression profiles of fresh DPCs isolated using the FDGS and CEDT methods were similar to those of traditionally isolated DPCs. DP-specific markers were expressed at significantly higher levels in freshly isolated DPCs than in traditionally isolated DPCs. Conclusions: Compared to traditional methods, the presented laboratory protocols were able to isolate fresh DPCs with high efficiency, thereby improving their research potential. [ABSTRACT FROM AUTHOR]

Background: Androgenetic alopecia (AGA) is common. While topical minoxidil remains the only FDA‐approved therapeutic for AGA, its efficacy is limited in stimulating clinically significant hair regrowth over the longer term. Oral minoxidil, which is used off‐label, is a promising alternative; however, its effectiveness and underlying mechanisms warrant further investigation. Aims: To elucidate the site of action and infer the physiological mechanisms underlying therapeutic responses to oral minoxidil in patients with AGA. Methods: Forty‐one patients with AGA underwent 6 months of low‐dose oral minoxidil treatment. Minoxidil sulfotransferase (SULT) activity was assayed in plucked scalp hair follicles. The primary outcome was hair growth after low‐dose oral minoxidil treatment for a minimum of 6 months, and the secondary outcome was SULT activity in hair follicles. Results: After 6 months of treatment, 26 (63.4%) patients experienced a clinical improvement in alopecia symptoms. The response rate was higher in men (19/26 [73.1%]) than in women (6/15 [40.0%]). Patients with low hair follicle SULT activity demonstrated a higher minoxidil response rate than those with high enzyme activity (85% vs. 43%, p = 0.009). Conclusions: Our findings indicate that low SULT activity within the hair follicles is associated with a favorable response to oral minoxidil therapy in patients with AGA. Further elucidation of the underlying mechanisms could significantly improve personalized therapeutic approaches through improved patient selection and the rational design of adjuvant treatments. [ABSTRACT FROM AUTHOR]

Skin‐derived precursor (SKPs) cells are multipotent stem cells found in the dermis that contribute to wound healing and induce hair follicle neogenesis when transplanted. The clinical application of adult human SKPs, however, is hindered by their loss of potency after in vitro expansion. To overcome this challenge, we aimed to isolate SKPs from human‐induced pluripotent stem cell‐derived skin organoids (SKOs), to enable mass production of these cells for therapeutics. We developed a protocol to isolate skin‐derived precursor‐like cells (SKP‐like cells) from human SKOs. SKP‐like cells derived from SKOs exhibited characteristic spheroid morphology and were capable of self‐renewal in defined SKP growth medium. Immunofluorescence analysis confirmed the expression of key markers, including SOX2, fibronectin and S100β, within the SKP‐like cells. The findings of this pilot study shed light on the potential of SKO‐derived SKP‐like cells for future hair regenerative applications. Furthermore, this research highlights the application of human SKOs as a valuable source for isolating progenitor cells, aiming to advance hair regeneration and restore skin function. [ABSTRACT FROM AUTHOR]

Introduction: Follicular delivery is one of the targeted drug delivery methods aiming to target the hair follicles. The accumulation and retention time of targeted drugs is enhanced when nanoparticles are used as drug carriers. Particle size is one of the important factors affecting the penetration and accumulation of particles in the hair follicles, and there is a controversy in different studies for the best particle size for follicular delivery. Mouse models are mostly used in clinical trials for dermal, transdermal, and follicular delivery studies. Also, it is essential to investigate the reliability of the results between human studies and mouse models. Methods: Curcumin-loaded nanostructured lipid carriers (NLCs), as a fluorescent agent, with three different particle size ranges were prepared using the hot homogenization method and applied topically on the mouse and human study groups. Biopsies were taken from applied areas on different days after using the formulation. The histopathology studies were done on the skin biopsies of both groups using confocal laser scanning microscopy (CLSM). We compared the confocal laser scanning microscope pictures of different groups, in terms of penetration and retention time of nanoparticles in human and mouse hair follicles. Results: The best particle size in both models was the 400 nm group but the penetration and accumulation of particles in human and mouse hair follicles were totally different even for the 400 nm group. In human studies, 400 nm particles showed good accumulation after seven days; this result can help to increase the formulation using intervals. Conclusion: The best particle size for human and mouse follicular drug delivery is around 400 nm and although mouse models are not completely suitable for follicular delivery studies, they can be used in some conditions as experimental models. [ABSTRACT FROM AUTHOR]

Background: Cashmere, known as "soft gold", is a highly prized fiber from Cashmere goats, produced by secondary hair follicles. Dermal papilla cells, located at the base of these follicles, regulate the proliferation and differentiation of hair matrix cells, which are essential for hair growth and cashmere formation. Recent studies emphasize the role of microRNAs (miRNAs) in controlling gene expression within these processes. Methods: This study centered on exploring the targeted regulatory interaction between miR-144 and the Lhx2 gene. Utilizing methodologies like miRNA target prediction, luciferase reporter assays, and quantitative PCR, they assessed the interplay between miR-144 and Lhx2. Dermal papilla cells derived from Cashmere goats were cultured and transfected with either miR-144 mimics or inhibitors to observe the subsequent effects on Lhx2 expression. Results: The results demonstrated that miR-144 directly targets the Lhx2 gene by binding to its mRNA, leading to a decrease in Lhx2 expression. This modulation of Lhx2 levels influenced the behavior of dermal papilla cells, affecting their ability to regulate hair matrix cell proliferation and differentiation. Consequently, the manipulation of miR-144 levels had a significant impact on the growth cycle of cashmere wool. Conclusions: The findings suggest miR-144 regulates hair follicle dynamics by targeting Lhx2, offering insights into hair growth mechanisms. This could lead to innovations in enhancing cashmere production, fleece quality, and addressing hair growth disorders. Future research may focus on adjusting miR-144 levels to optimize Lhx2 expression and promote hair follicle activity. [ABSTRACT FROM AUTHOR]

Background: The cashmere goat is a biological resource that mainly produces cashmere. Cashmere has a soft hand feel and good luster, with high economic value. The quality and yield of cashmere are determined by the process of hair follicle development during the embryonic period. Methods: In this study, the skin of the Inner Mongolia cashmere goat at different embryonic stages (45, 55, 65, and 75d) was collected, and the differentially expressed lncRNA MSTRG.20890.1 at 75d was obtained by screening. Dual luciferase reporter gene system, qRT-PCR, and EDU experiments were used to verify further the regulatory role and molecular mechanism of the lncRNA in dermal fibroblasts. Results: Based on the transcriptome database of Inner Mongolia cashmere goat skin at different embryonic stages, which was previously constructed by our group, according to the characteristics of hair follicle development in the embryonic stage, we screened out the lncRNA MSTRG.20890.1 that was down-expressed on the 75-SHFINI day of the embryonic stage. We found that lncRNA MSTRG.20890.1 was mainly located in the cytoplasm of cells, and it could inhibit the proliferation and directional migration of dermal fibroblasts through the chi-miR-24-3p/ADAMTS3 signaling axis, thereby inhibiting the formation of dermal papilla structure at embryonic stage. Conclusions: This study revealed that lncRNA MSTRG.20890.1 regulated secondary hair follicle morphogenesis and development in cashmere goats through the chi-miR-24-3p/ADAMTS3 signaling axis. [ABSTRACT FROM AUTHOR]

Oxytocin has various effects ranging from promoting labor in pregnant women to alleviating stress. Recently, we reported the hair growth-promoting effects of oxytocin in hair follicle organoids. However, its clinical application faces challenges such as rapid degradation in vivo and poor permeability due to its large molecular weight. Therefore, in this study, we investigated the effects of the oxytocin receptor (OXTR) agonists WAY267464 and LIT001 as alternatives to oxytocin on hair growth. Human dermal papilla (DP) cells were cultured in WAY267464 or LIT001-supplemented medium. The addition of WAY267464 and LIT001 increased the expression of hair growth-related genes in DP cells. We tested the hair growth-promoting effects of WAY267464 and LIT001 using hair follicle organoids in vitro and found that they significantly promoted hair follicle sprouting. Thus, our findings indicate that WAY267464 and LIT001 are potential hair growth agents and may encourage further research on the development of novel hair growth agents targeting OXTR in patients with alopecia. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aldehyde dehydrogenase 2 (ALDH2) levels in human hair follicles (HFs) are significantly increased during the anagen phase. • ALDH2 expression is primarily localized in the outer root sheath of human HFs. • Activation of ALDH2 in HFs leads to anagen induction and subsequent hair shaft elongation. • ALDH2 activation triggers reactive oxygen species scavenging in HFs and upregulates β-catenin signaling. • Modulation of ALDH2 may be a promising therapeutic approach for inducing the anagen phase, providing novel insights into the impact of ALDH2 activation on HFs. Hair loss is a common phenomenon associated with various environmental and genetic factors. Mitochondrial dysfunction-induced oxidative stress has been recognized as a crucial determinant of hair follicle (HF) biology. Aldehyde dehydrogenase 2 (ALDH2) mitigates oxidative stress by detoxifying acetaldehyde. This study investigated the potential role of ALDH2 modulation in HF function and hair growth promotion. To evaluate the effects of ALDH2 activation on oxidative stress in HFs and hair growth promotion. The modulatory role of ALDH2 on HFs was investigated using an ALDH2 activator. ALDH2 expression in human HFs was evaluated through in vitro immunofluorescence staining. Ex vivo HF organ culture was employed to assess hair shaft elongation, while the fluorescence probe 2′,7′- dichlorodihydrofluorescein diacetate was utilized to detect reactive oxygen species (ROS). An in vivo mouse model was used to determine whether ALDH2 activation induces anagen. During the anagen phase, ALDH2 showed significantly higher intensity than that in the telogen phase, and its expression was primarily localized along the outer layer of HFs. ALDH2 activation promoted anagen phase induction by reducing ROS levels and enhancing reactive aldehyde clearance, which indicated that ALDH2 functions as a ROS scavenger within HFs. Moreover, ALDH2 activation upregulated Akt/GSK 3β/β-catenin signaling in HFs. Our findings highlight the hair growth promotion effects of ALDH2 activation in HFs and its potential as a promising therapeutic approach for promoting anagen induction. [ABSTRACT FROM AUTHOR]

Objective Comparison of efficacy of intralesional triamcinolone versus 308nm Excimer laser in the treatment of localized alopecia areata. Methods This study was done at dermatology unit Khyber teaching Hospital Peshawar, from 1st January 2023 to 30th June, 2023.All patients were allocated randomly into two groups by block randomization. Group A received 308 nm excimer laser twice weekly and group B got intralesional triamcinolone (10 mg/1ml) every three weeks. Patients were followed up at 12 weeks and mean SALT score at base line and follow up were documented. A response to treatment was labeled as effective if there was >75% hair growth (improvement) from baseline. Results As per calculated sample size, a total of 92 patients were equally divided into two groups, A and B, i.e. 46 patients in each group. Result analysis in our study showed that in group A, mean SALT score decreased from 15.44 at baseline to 5.42 at 12 weeks follow, with excimer Laser. Likewise, the mean SALT score in group B decreased from 14.64 at base line to a mean value of 6.35 at 12 week follow up with intralesional steroid treatment. From an efficacy point of view, group A showed an efficacy (>75% hair re-growth at 12 week follow up) of 56.5% while group B showed 67.4%. Conclusion Our study concludes that intralesional triamcinolone is more effective than 308 nm Excimer laser in the treatment of localized Alopecia areata. [ABSTRACT FROM AUTHOR]

The hair follicle can cycle throughout a lifetime, undergoing periods of growth (anagen), regression (catagen) and relative quiescence (telogen). The time that a hair follicle spends in each of these stages is crucial to determine the length of hair fibre that it produces. Perturbations in this regard can manifest in various hair diseases such as anagen effluvium, or acute and chronic telogen effluvium. The established 'dogma' when considering how many hair follicles there are in each stage has long been that the majority are in anagen (85%–90%), followed by telogen (10%–15%) and catagen (1%–2%). These values are based on various studies using different methodologies such as hair plucking, phototrichograms and histology. However, these methods have flaws when it comes to differentiating between catagen and telogen follicles. We sought to determine the catagen: telogen ratio through the ex vivo stereomicroscopic examination of hundreds of hair follicles removed from the occipital scalp of 14 Caucasian males during routine hair transplantation procedures. Using this methodology, and in agreement with a similar observation by another research group, we found that the percentage of catagen hair follicles was higher (7.5%) than telogen (3.5%) in all patients assessed. Consequently, we believe that the percentage of catagen follicles is clearly underestimated and therefore challenge the current established dogma. [ABSTRACT FROM AUTHOR]

Background: In pigs, a hair whorl refers to hairs that form a ring of growth around the direction of the hair follicle at the dorsal hip. In China, a hair whorl is considered a negative trait that affects marketing, and no studies have been conducted to demonstrate whether hair whorl affects pig performance and provide an explanation for its genetic basis. Methods: Performance-measured traits and slaughter-measured traits of hair whorl and non-hair whorl pigs were differentially analyzed, followed by genome-wide association analysis (GWAS) and copy number variation (CNV) methods to investigate the genetic basis of hair whorl in pigs. Results: Differential analysis of 2625 pigs (171 hair whorl and 2454 non-hair whorl) for performance measures showed that hair whorl and non-hair whorl pigs differed significantly (p < 0.05) in traits such as live births, total litter size, and healthy litter size (p < 0.05), while differential analysis of carcass and meat quality traits showed a significant difference only in the 45 min pH (p = 0.0265). GWAS identified 4 SNP loci significantly associated with the hair whorl trait, 2 of which reached genome-significant levels, and 23 candidate genes were obtained by annotation with the Ensembl database. KEGG and GO enrichment analyses showed that these genes were mainly enriched in the ErbB signaling, endothelial apoptosis regulation, and cell proliferation pathways. In addition, CNV analysis identified 652 differential genes between hair whorl and non-hair whorl pigs, which were mainly involved in the signal transduction, transcription factor activity, and nuclear and cytoplasmic-related pathways. Conclusions: The candidate genes and copy number variation differences identified in this study provide a new theoretical basis for pig breeding efforts. [ABSTRACT FROM AUTHOR]

Trichofolliculoma is a rare benign, hamartomatous adnexal tumour of the skin. Aetiology seems to be unclear. It is usually seen in adults, with no gender predilection. The most commonly involved sites are the face and scalp. It appears as a papule or nodule with small protruding hairs, which is a classic feature of the tumour. It has unique diagnostic and histopathological features that help in making a definitive diagnosis. Here, we report an exemplary case of an adult male patient aged 45 years with a gradual progressive diffuse swelling on the left side of the face for 1.5 years. Clinically, it was diagnosed as a sebaceous cyst, but after the biopsy histopathological evaluation was performed, and the diagnosis was confirmed as trichofolliculoma.

Sebaceous glands (SGs) release oils that protect our skin, but how these glands respond to injury has not been previously examined. Here, we report that SGs are largely self-renewed by dedicated stem cell pools during homeostasis. Using targeted single-cell RNA sequencing, we uncovered both direct and indirect paths by which resident SG progenitors ordinarily differentiate into sebocytes, including transit through a Krt5+PPARγ+ transitional basal cell state. Upon skin injury, however, SG progenitors depart their niche, reepithelialize the wound, and are replaced by hair-follicle-derived stem cells. Furthermore, following targeted genetic ablation of >99% of SGs from dorsal skin, these glands unexpectedly regenerate within weeks. This regenerative process is mediated by alternative stem cells originating from the hair follicle bulge, is dependent upon FGFR2 signaling, and can be accelerated by inducing hair growth. Altogether, our studies demonstrate that stem cell plasticity promotes SG durability following injury.