Catagen Phase Research Articles

Anti-Hair Loss Effects of the DP2 Antagonist in Human Follicle Dermal Papilla Cells

Prostaglandin D2 (PGD2) levels are high in the balding areas of human scalps, and PGD2 has been found to inhibit hair growth. It is known that the inhibition of the PGD2 receptor can promote hair growth by preventing hair follicles from entering the catagen phase. Thus, we identified an antagonist of DP2, the receptor for PGD2, as a potential treatment for hair loss using an AI-based DeepZema® drug development program. In this study, we identified that the DP2 antagonist (DP2A) could ameliorate alopecia in human follicle dermal papilla cells (HFDPCs) that were stimulated by dihydrotestosterone (DHT), a known molecule related to hair loss. We observed that the DP2A promoted wound healing efficiency and increased alkaline phosphatase levels in the HFDPCs that were damaged with DHT. In addition, we found that the DP2A diminished the reactive oxygen species (ROS) levels generated in the DHT-damaged HFDPCs. We confirmed that the DP2A effectively recovered the membrane potential of mitochondria in these cells. We also demonstrated that the DP2A enhanced the phosphorylation levels of both Akt and ERK in the HFDPCs that were damaged with DHT. Notably, we revealed that the DP2A slightly enlarged the three-dimensional spheroid size in these cells and confirmed that the DP2A improved hair growth in the organ culture of human hair follicles. Taken together, we suggest that DP2A has therapeutic effects on HFDPCs that are damaged by DHT and holds promise as a potential treatment for treating hair loss.

Hair growth-promoting effects of Enz_MoriL on human dermal papilla cells through modulation of the Wnt/β-Catenin and JAK-STAT signaling pathways.

Enz_MoriL is a naturally occurring substance extracted from the leaves of Morus alba L. through enzymatic conversion. Historically, M. alba L. has been recognized for its potential to promote hair regrowth. However, the precise mechanism by which Enz_MoriL affects human hair follicle dermal papilla cells (hDPCs) remains unclear. The aim of this study was to investigate the molecular basis of Enz_MoriL's effect on hair growth in hDPCs. Interferon-gamma (IFN-γ) was used to examine the effects of Enz_MoriL on hDPCs during the anagen and catagen phases, as well as under conditions mimicking alopecia areata (AA). Enz_MoriL demonstrated the ability to promote cell proliferation in both anagen and catagen stages. It increased the levels of active β-catenin in the catagen stage induced by IFN-γ, leading to its nuclear translocation. This effect was achieved by increasing the phosphorylation of GSK3β and decreasing the expression of DKK-1. This stimulation induced proliferation in hDPCs and upregulated the expression of the Wnt family members 3a, 5a, and 7a at the transcript level. Additionally, Enz_MoriL suppressed JAK1 and STAT3 phosphorylation, contrasting with IFN-γ, which induced them in the catagen stage. In conclusion, Enz_MoriL directly induced signals for anagen re-entry into hDPCs by affecting the Wnt/β-catenin pathway and enhancing the production of growth factors. Furthermore, Enz_MoriL attenuated and reversed the interferon-induced AA-like environment by blocking the JAK-STAT pathway in hDPCs.

Necrosulfonamide promotes hair growth and ameliorates DHT-induced hair growth inhibition

BackgroundAlopecia affects patients' appearance and psychology. Mixed-lineage kinase domain-like pseudokinase (MLKL)-mediated necroptosis plays a role in various skin diseases, but its effect on hair growth is unclear. ObjectiveTo investigate the effects of MLKL on hair growth and its regulatory mechanisms and to determine the potential clinical value of Necrosulfonamide (NSA, a MLKL-targeting inhibitor) in promoting hair growth and counteracting dihydrotestosterone (DHT) inhibition of hair growth. MethodsThe expression level of MLKL was detected in the scalp of androgenetic alopecia (AGA) patients and the skin tissues of mice. Knock down MLKL expression or use NSA to observe hair growth in vivo and in vitro. ResultsIn AGA patients, MLKL expression is elevated in the alopecia areas. In mice, MLKL is significantly expressed in the outer root sheath (ORS) cells of hair follicles, peaking during the catagen phase. Knockdown expression of MLKL in mice skin promoted hair growth. NSA enhanced hair growth and prevented hair follicle regression via the Wnt signaling. Reduced MLKL boosts ORS cell proliferation without directly impacting DPCs' growth. Interestingly, NSA boosts DPCs' proliferation and induction when co-cultured with ORS cells. Besides, NSA alleviated the inhibition of DHT on hair growth in vivo and vitro. ConclusionNSA inhibited the activation of MLKL in ORS cells, promoted the activation of Wnt signal in DPC cells, and improved the inhibition of hair growth by DHT, illuminating a new alopecia mechanism and aiding anti-alopecia drug development.

Salvianolic Acid B Reduces Oxidative Stress to Promote Hair-Growth in Mice, Human Hair Follicles and Dermal Papilla Cells.

Existing research links oxidative stress and inflammation to hair loss. Salvianolic acid B (SAB) is known for its anti-oxidative, anti-inflammatory, and other beneficial pharmacological properties. To assess the efficacy of SAB in modulating hair growth. In vivo experiments were conducted using C57BL/6 mice to evaluate the effects of SAB on hair and skin parameters. The study involved ex vivo analysis of human hair follicles (HFs) for hair shaft length and hair growth cycle assessment. In vitro, human dermal papilla cells (hDPCs) were cultured with SAB, and their proliferation, protection against H2O2-induced oxidative damage, and gene/protein expression alterations were examined using various analytical techniques, including Real-Time Cell Analysis (RTCA), DCFH-DA Assay, RNA-seq, and KEGG pathway analysis. SAB treatment in mice significantly improved hair growth and vascularization by day 21. In human HFs, SAB extended hair shaft length and delayed the transition to the catagen phase. SAB-treated hDPCs showed a notable decrease in the expression of oxidation-antioxidation-related genes and proteins, including reduced phosphorylation levels of ERK and p38. The study indicates that SAB promotes hDPC proliferation and offers protection against oxidative stress, highlighting its potential as a therapeutic agent for enhancing hair growth and treating hair loss.

Efficacy of derinat as a treatment for murine and androgenetic alopecia (AGA) patients

BackgroundAndrogenetic alopecia (AGA), one of the most common types of hair loss, is associated with oxidative stress, inflammation and aging. Derinat, a transient receptor potential canonical channels (TRPCs) inhibitor, restrains TRPCs-mediated increase intracellular Ca2+ signaling, which initiates the skin aging process with intracellular reactive oxygen species (ROS) accumulation. This study investigated whether Derinat protected skin from oxidative stress-induced damage and aging, thus inhibiting AGA pathogenesis.MethodsThe lifespan of Caenorhabditis elegans was measured to examine the capacity of Derinat to oppose the oxidative stress induced-aging process, which drives the hair cycle from anagen to catagen phase. The experiments that used BALB/c-nu and C57BL/6 mice determined the effects of Derinat on hair cycle and oxidative stress in skin. To further apply Derinat to clinical study, the resulting relationship between AGA pathogenesis and TRPCs-regulated oxidative stress was confirmed using the bioinformatics approach. We consequently used the parameters of hair density, hair diameter, hair recovery and quality of life index to evaluate the effect of Derinat treatment on AGA subjects.ResultsDerinat restrained the oxidative stress induced-aging process sufficiently to extend the lifespan of worms. Derinat also changed the hair growth patterns of mice by maintenance of the hair cycle at the anagen phase. This efficacy was due to reduction of TRPCs-mediated ROS accumulation. Because the bioinformatics analysis found that AGA pathogenesis is associated with TRPCs-regulated oxidative stress and inflammation, treatment with Derinat in AGA subjects increased positive outcomes of oral medication while mitigating the impairment of AGA subjects’ quality of life.ConclusionsDerinat restrains AGA pathogenesis and may provide a new therapeutic approach for treating AGA. ClinicalTrials.gov Identifier NCT05450861, https://register.clinicaltrials.gov, date of registration 07/11/2022.Trial registrationClinicalTrials.gov Identifier NCT05450861, https://register.clinicaltrials.gov, date of registration 07/11/2022

VDR is an essential regulator of hair follicle regression through the progression of cell death.

Vitamin D receptor (VDR) is essential for hair follicle homeostasis as its deficiency induces hair loss, although the mechanism involved remains unknown. Our research shows that, in Vdr-knockout mice, the hair cycle is halted during the catagen stage, preceding alopecia. In addition, in Vdr-knockout hair follicles, epithelial strands that normally regress during the catagen phase persist as "surviving epithelial strands." Single-cell RNA sequencing analysis suggests that these surviving epithelial strands are formed by cells in the lower part of the hair follicle. These findings emphasize the importance of the regression phase in hair follicle regeneration and establish VDR as a regulator of the catagen stage.

SARS-CoV-2 Infection-A Trigger Factor for Telogen Effluvium: Review of the Literature with a Case-Based Guidance for Clinical Evaluation.

Telogen effluvium post-COVID-19 is a condition characterized by the diffuse and reversible loss of scalp hair in the period following infection with SARS-CoV-2, and it is currently the second cause of alopecia in women. In the context of the COVID-19 infection, intense psychological stress contributes to alopecia appearance, along with systemic inflammation, autoimmune reactions, oxidative stress, and virally induced hypoxia. Cytokines with proinflammatory action and vasoactive substances negatively modulate the metabolism of some molecules, such as proteoglycans, involved in the hair follicle's growth cycle. Studies show that a large percentage of hairs will suddenly enter the catagen phase during a moderate to severe COVID-19 infection. In the present paper, we update the data from the literature with a clinical example. Our case highlighted that the telogen effluvium after infections with SARS-CoV-2 is reversible with appropriate dermatological treatment. For therapeutic success, informing the patient about this pathology's self-limited and reversible character is essential to reduce the emotional stress that may aggravate the disease.

Promotion of hair growth by Lactobacillus and fermented traditional Korean berry in C57BL/6 mice

Hair loss is the state of losing hair from the scalp or entire body when new hair does not replace the hair that has fallen out. Currently, remedies such as oral finasteride and topical minoxidil are commonly used. However, these drugs may have temporary effects and cause side effects such as depression, irregular heartbeat and weight gain when used long term. Therefore, an alternative hair growth promoting agent is needed. The hair follicle undergoes anagen, catagen, and telogen phase which affect hair growth, and this hair-growth cycle is regulated by growth factors, cytokines, and hormones. Some studies reported that the gut microbiome (GM) regulates the transition between the hair growth cycle by producing hair growth-related factors and nutrients. Also, inflammation by GM affects the cascade of the inflammation in the hair follicle, which may lead to hair growth arrest. Previous studies showed strains of Lactobacillus (LAB) have anti-oxidative and anti-inflammatory effects in an HT-29 human colon epithelial cell model and an HaCaT human keratinocyte cell model. Also, traditional Korean berry has anti-inflammatory effects in an HT-29 model. Thus, LAB and fermented traditional Korean berry by LAB (FB) may promote hair growth by regulating gut microbiome. This study investigated the effect of LAB and FB on hair growth in vivo. Six-week-old male C57BL/6 mice were used for evaluating the hair growth-promoting effects of the LAB and FB. The dorsal hair of mice was depilated, and they were orally treated with LAB at 1010 CFU/kg and FB at 250mg/kg daily for 22 days. As a result, the hair re-growth rate was significantly increased in LAB and FB groups compared with the control group. In the histological analysis of skin, FB increased the number of hair follicle and subcutaneous fat layer thickness. The mRNA expression levels of hair growth-related growth factors such as VEGF and IGF-1 are significantly increased in colon and skin. Moreover, Treatment of LAB and FB changed the composition of the microbiome and short chain fatty acids in mice. Altogether, LAB and FB supplementation may promote hair growth by regulating growth factors and altering gut microbiota compositions. In conclusion, strain of LAB and FB are potential novel approaches for hair growth promotion. This work was supported by Korea Testing Laboratory This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Mechanistic synergy of hair growth promotion by the Avicennia marina extract and its active constituent (avicequinone C) in dermal papilla cells isolated from androgenic alopecia patients.

Androgenic alopecia (AGA) is associated with an increased production of 5α-dihydrotestosterone (DHT) by steroid-5α-reductase (5α-R). Crude extracts from Avicennia marina (AM) and its active constituent, avicequinone C (AC), can inhibit 5α-R. We have, herein, explored the potential use of the AM extract and of AC as anti-AGA agents. To this end, we employed human dermal papilla cells (DPCs) isolated from AGA patients' hair that express 5α-R type-1 as well as the androgenic receptor (AR) at high levels. Our in vitro experiments revealed that the AM extract (10 μg/mL) and the AC (10 μM) exhibit multiple actions that interfere with the mechanism that causes AGA. Beside acting as 5α-R inhibitors, both preparations were able to inhibit either the DHT-AR complex formation or its translocation from the cytoplasm into the nucleus (the site of DHT's action). The treatments also increased the gene expression of growth factors in DPCs; these factors play important roles in the angiogenesis associated with hair growth. Moreover, the AM extract suppressed the apoptotic pathway, thereby postponing the initiation of the catagen phase. Taken together, our findings suggest that the AM extract and the AC could serve as natural sources for hair growth promotion and AGA treatment.

1428 DKK2 and SOSTDC1 cooperate to initiate the first catagen phase of the hair follicle growth cycle

1428 DKK2 and SOSTDC1 cooperate to initiate the first catagen phase of the hair follicle growth cycle

Effect of Plantago asiatica L. extract on the anagen phase in human hair follicle dermal papilla cells.

The hair growth cycle consists of the anagen, catagen, and telogen phases, and hair follicle dermal papilla (HDP) cells of human hair play a role in the initiation and maintenance of the anagen phase. Reduction in HDP cells contributes to hair loss; however, the limited treatment options are associated with negative side effects. Therefore, a naturally derived substance with hair loss-preventing properties is needed. We investigated the hair growth-stimulating activities of Plantago asiatica L. extract (PAE) and its molecular mechanism in HDP cells. Cell proliferation was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide solution. Relative mRNA and protein expression levels of hair growth factors were determined using quantitative real-time polymerase chain reaction and western blotting, respectively. Additionally, a tube formation assay was performed in human umbilical vein endothelial cells (HUVEC). Plantago asiatica L. extract significantly increased the cell proliferation and expression of hair growth factors, including keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF), fibroblast growth factor 2 (FGF2) and MYC, in HDP cells. Moreover, PAE led to the accumulation of β-catenin by promoting the phosphorylation of glycogen synthase kinase-3 beta (GSK-3β) at Ser9 and cAMP response element-binding protein (CREB) at Ser133 via phosphorylation of extracellular signal-regulated kinase (ERK) (Thr202/Tyr204). PAE also increased tube formation in HUVECs, which promoted angiogenesis for the anagen phase. Plantago asiatica L. extract amplified tube formation and production of growth factors (KGF, VEGF) via the activation of GSK-3β/β-catenin and mitogen-activated protein kinase (MAPK)/CREB signaling pathways, demonstrating its potential to safely promote hair growth by inducing the anagen phase.

Investigation of Glypican-4 and -6 by Infrared Spectral Imaging during the Hair Growth Cycle

The expression of glypicans in different hair follicle (HF) compartments is still poorly understood. Heparan sulfate proteoglycans (HSPGs) distribution in HF is classically investigated by conventional histology, biochemical analysis, and immunohistochemistry. Our previous study proposed a novel approach to assess hair histology and glypican-1 (GPC1) distribution changes in the HF at different phases of the hair growth cycle using infrared spectral imaging (IRSI). We show in the present manuscript for the first time complementary data on the distribution of glypican-4 (GPC4) and glypican-6 (GPC6) in HF at different phases of the hair growth cycle using IR imaging. Findings were supported by Western blot assays focusing on the GPC4 and GPC6 expression in HFs. Like all proteoglycan features, the glypicans are characterized by a core protein to which sulfated and/or unsulfated glycosaminoglycan (GAG) chains are covalently linked. Our study demonstrates the capacity of IRSI to identify the different HF tissue structures and to highlight protein, proteoglycan (PG), GAG, and sulfated GAG distribution in these structures. The comparison between anagen, catagen, and telogen phases shows the qualitative and/or quantitative evolution of GAGs, as supported by Western blot. Thus, in one analysis, IRSI can simultaneously reveal the location of proteins, PGs, GAGs and sulfated GAGs in HFs in a chemical and label-free manner. From a dermatological point of view, IRSI may constitute a promising technique to study alopecia.

Regulation of secondary hair follicle cycle in cashmere goats by miR-877-3p targeting IGFBP5 gene.

Cashmere, a highly valuable animal product derived from cashmere goats, holds significant economic importance. MiRNAs serve as crucial regulators in the developmental processes of mammalian hair follicles. Understanding the regulation of miRNAs during the hair follicle cycle is essential for enhancing cashmere quality. In this investigation, we employed high-throughput sequencing technology to analyze the expression profiles of miRNAs in the secondary hair follicles of Jiangnan cashmere goats at different stages. Through bioinformatics analysis, we identified differentially expressed miRNAs (DE miRNAs). The regulatory relationships between miRNAs and their target genes were verified using multiple techniques, including RT-qPCR, western blot, Dual-Luciferase Reporter, and CKK-8 assays. Our findings revealed the presence of 193 DE miRNAs during various stages of the hair follicle cycle in Jiangnan cashmere goats. Based on the previously obtained mRNA data, the target genes of DE miRNA were predicted, and 1,472 negative regulatory relationships between DE miRNAs and target genes were obtained. Notably, the expression of chi-miR-877-3p was down-regulated during the telogen (Tn) phase compared to the anagen (An) and catagen (Cn) phases, while the IGFBP5 gene exhibited up-regulation. Further validation experiments confirmed that overexpression of chi-miR-877-3p in dermal papilla cells suppressed IGFBP5 gene expression and facilitated cell proliferation. The results of this study provide novel insights for analyzing the hair follicle cycle.

Hair Regrowth with Novel Hemp Extract: A Case Series.

The endocannabinoid system (ECS), discovered in the 1990s, is a system involved with maintaining cellular homeostasis by down-regulating the damaging inflammatory responses and upregulating regenerative processes. Cannabidiol (CBD), tetrahydrocannabivarin (THCV), and cannabidivarin (CBDV) are all phytocannabinoids found in varying quantities in hemp extract. These three cannabinoids have novel therapeutic effects on hair regrowth through the ECS. The method of action is different from and synergistic with current hair regrowth therapies. The three cannabinoids are fat-soluble and poorly absorbed past the epidermis, but topical application easily reaches hair follicles where they act as partial or full CB1 antagonist and agonist of transient receptor potential vanilloid-1 (TRPV1) and vanilloid receptor-4 (TRPV4). All these ECS receptors relate to hair follicle function. Blocking the CB1 receptor on the hair follicle has been shown to result in hair shaft elongation; in addition, the hair follicle cycle (anagen, catagen, and telogen phases) is controlled by TRPV1. The effects of CBD on hair growth are dose dependent and higher doses may result in premature entry into the catagen phase through a different receptor known as TRPV4. CBD has also been shown to increase Wnt signaling, which causes dermal progenitor cells to differentiate into new hair follicles and maintains anagen phase of the hair cycle. This study was conducted on subjects with androgenetic alopecia (AGA), as follow-up to a prior published study using hemp extract high in CBD without CBDV or THCV. That study showed an average 93.5% increase in hair numbers after 6 months of use. This subsequent study is being done to determine if daily topical application of a hemp-oil high in CBD, THCV, and CBDV concentrations would result in improved hair regrowth in the area of the scalp most affected by AGA. A case series study was done of 31 (15 men and 16 women, 27 Caucasian, 2 Asian, and 1 mixed race) subjects with AGA. They used a once-daily topical hemp extract formulation, averaging about 33 mg/day for 6 months. A hair count of the greatest area of alopecia was carried out before treatment was started and again after 6 months of treatment. To facilitate consistent hair count analysis, a permanent tattoo was placed at the point for maximum hair loss on the scalp. The subjects were also asked to qualitatively rate their psychosocial perception of "scalp coverage" improvement after the study was completed. The qualitative scale included "very unhappy," "unhappy," "neutral," "happy," and "very happy." The subjects were photographed in a standard manner before and after the study. The photographs were compared for improvements in "scalp coverage" by an independent physician. The qualitative scale included "none," "mild," "moderate," and "extensive" improvement of scalp coverage. The results revealed that all subjects had some regrowth. This ranged from 31.25% (from 16 to 21 hairs) to 2000% (from 1 to 21 hairs). The average increase was statistically significant 246% (15.07 hairs/cm2 increase) in men and 127% (16.06 hairs/cm2) in women. There were no reported adverse effects. All subjects rated their psychosocial perception of the effects of the hair loss, as "happy" or "very happy." Independent review of the photographs revealed evidence of "mild" to "extensive" scalp coverage improvements for all of the subjects. Although the exact mechanism of therapeutic effects is not known, THCV and CBDV are most likely functioning as full CB1 receptor neutral antagonists and CBD is most likely functioning as a partial CB1 receptor antagonist and potentially through Wnt messaging. All three cannabinoids were functioning as TRPV1 agonists. The addition of menthol through the peppermint extract is probably acting through promoting a rapid onset of anagen phase. This topical hemp formulation was superior to oral finasteride, 5% minoxidil once daily foam and CBD topical extract alone. Since this hemp extract works through novel mechanisms entirely different from both finasteride and minoxidil, it can be used in conjunction with these current drugs and would be expected to have synergistic effects. However, safety and efficacy of this combination would be to be evaluated.

Ginsenoside Re prevents 3-methyladenine-induced catagen phase acceleration by regulating Wnt/β-catenin signaling in human dermal papilla cells

BackgroundThe human hair follicle undergoes cyclic phases—anagen, catagen, and telogen—throughout its lifetime. This cyclic transition has been studied as a target for treating hair loss. Recently, correlation between the inhibition of autophagy and acceleration of the catagen phase in human hair follicles was investigated. However, the role of autophagy in human dermal papilla cells (hDPCs), which is involved in the development and growth of hair follicles, is not known. We hypothesized that acceleration of hair catagen phase upon inhibition of autophagy is due to the downregulation of Wnt/β-catenin signaling in hDPCs, and that components of Panax ginseng extract can increase the autophagic flux in hDPCs. MethodsWe generated an autophagy-inhibited condition using 3-methyladenine (3-MA), a specific autophagy inhibitor, and investigated the regulation of Wnt/β-catenin signaling using the luciferase reporter assay, qRT-PCR, and western blot analysis. In addition, cells were cotreated with ginsenoside Re and 3-MA and their roles in inhibiting autophagosome formation were investigated. ResultsWe found that the unstimulated anagen phase dermal papilla region expressed the autophagy marker, LC3. Transcription of Wnt-related genes and nuclear translocation of β-catenin were reduced after treatment of hDPCs with 3-MA. In addition, treatment with the combination of ginsenoside Re and 3-MA changed the Wnt activity and hair cycle by restoring autophagy. ConclusionsOur results suggest that autophagy inhibition in hDPCs accelerates the catagen phase by downregulating Wnt/β-catenin signaling. Furthermore, ginsenoside Re, which increased autophagy in hDPCs, could be useful for reducing hair loss caused by abnormal inhibition of autophagy.

Telogen Effluvium and COVID-19: a case and a brief review of literature

COVID-19 is a new disease that has brought a great impact on global morbidity and mortality. There have been increasingly frequent reports of persistent symptoms and/or clinical manifestations attributed to COVID-19 after the acute phase of the disease. In this article, we present a case of post-COVID-19 telogen effluvium in a 39-year-old hypertensive and obese patient who looked for medical attention due to massive hair loss. Previous history of moderate COVID-19 4 months ago. After investigation and exclusion of other possible causes of telogen effluvium well established in the literature, the condition was attributed to the previous episodeof COVID-19. Persistent fever, the cytokine storm, and the entire immunological cascade of COVID-19 canlead to apoptosis of the keratinocytes of the hair follicles, initiating the catagen phase early followed by the telogen phase with a consequent capillary release. Late symptoms possibly secondary to COVID-19 should receive attention and interest from the medical and scientific community. As it is a new disease, whose late consequences are not yet fully known/elucidated, careful observation and careful clinical follow-up of these patients are recommended.

Gender-Difference in Hair Length as Revealed by Crispr-Based Production of Long-Haired Mice with Dysfunctional FGF5 Mutations.

Fibroblast growth factor 5 (FGF5) is an important molecule required for the transition from anagen to catagen phase of the mammalian hair cycle. We previously reported that Syrian hamsters harboring a 1-bp deletion in the Fgf5 gene exhibit excessive hair growth in males. Herein, we generated Fgf5 mutant mice using genome editing via oviductal nucleic acid delivery (GONAD)/improved GONAD (i-GONAD), an in vivo genome editing system used to target early embryos present in the oviductal lumen, to study gender differences in hair length in mutant mice. The two lines (Fgf5go-malc), one with a 2-bp deletion (c.552_553del) and the other with a 1-bp insertion (c.552_553insA) in exon 3 of Fgf5, were successfully established. Each mutation was predicted to disrupt a part of the FGF domain through frameshift mutation (p.Glu184ValfsX128 or p.Glu184ArgfsX128). Fgf5go-malc1 mice had heterogeneously distributed longer hairs than wild-type mice (C57BL/6J). Notably, this change was more evident in males than in females (p < 0.0001). Immunohistochemical analysis revealed the presence of FGF5 protein in the dermal papilla and outer root sheath of the hair follicles from C57BL/6J and Fgf5go-malc1 mice. Histological analysis revealed that the prolonged anagen phase might be the cause of accelerated hair growth in Fgf5go-malc1 mice.

Staphylococcus epidermidis Cicaria, a Novel Strain Derived from the Human Microbiome, and Its Efficacy as a Treatment for Hair Loss.

The skin tissue of the scalp is unique from other skin tissues because it coexists with hair, and many differences in microbial composition have been confirmed. In scalp tissues, hair loss occurs due to a combination of internal and external factors, and several studies are being conducted to counteract this. However, not many studies have addressed hair loss from the perspective of the microbiome. In this study, subjects with hair loss and those with normal scalps were set as experimental and control groups, respectively. In the experimental group, hair loss had progressed, and there was a large difference in microbiome composition compared to the group with normal scalps. In particular, differences in Accumulibacter, Staphylococcus, and Corynebacterium were found. From Staphylococcus epidermidis Cicaria, two active components were isolated as a result of repeated column chromatography. Spectroscopic data led to the determination of chemical structures for adenosine and biotin. Fractions were obtained, and ex vivo tests were conducted using hair follicles derived from human scalp tissue. When the microbiome adenosine-treated group was compared to the control group, hair follicle length was increased, and hair root diameter was maintained during the experimental periods. In addition, the Cicaria culture medium and the microbial adenosine- and biotin-treated groups maintained the anagen phase, reducing progression to the catagen phase in the hair growth cycle. In conclusion, it was confirmed that the Cicaria culture medium and the microbial adenosine and biotin derived from the culture were effective in inhibiting hair loss.

Connarus semidecandrus Jack Exerts Anti-Alopecia Effects by Targeting 5α-Reductase Activity and an Intrinsic Apoptotic Pathway.

There is a growing demand for hair loss treatments with minimal side effects and recurrence potential. Connarus semidecandrus Jack has been used as a folk medicine for fever in tropical regions, but its anti-alopecia effects remain unclear. In this study, the anti-androgenic alopecia effect of an ethanol extract of Connarus semidecandrus Jack (Cs-EE) was demonstrated in a testosterone-induced androgenic alopecia (AGA) model, in terms of the hair–skin ratio, hair type frequency, and hair thickness. The area of restored hair growth and thickened hair population after Cs-EE treatment showed the hair-growth-promoting effect of Cs-EE. Histological data support the possibility that Cs-EE could reduce hair loss and upregulate hair proliferation in mouse skin by shifting hair follicles from the catagen phase to the anagen phase. Western blotting indicated that Cs-EE reduced the expression of the androgenic receptor. Cs-EE treatment also inhibited programmed cell death by upregulating Bcl-2 expression at the mRNA and protein levels. The anti-alopecia effect of Cs-EE was confirmed by in vitro experiments showing that Cs-EE had suppressive effects on 5-α reductase activity and lymph node carcinoma of the prostate proliferation, and a proliferative effect on human hair-follicle dermal papilla (HDP) cells. Apoptotic pathways in HDP cells were downregulated by Cs-EE treatment. Thus, Cs-EE could be a potential treatment for AGA.

CXCL12 inhibits hair growth through CXCR4.

CXCL12 and its receptors, which are highly expressed in the skin, are associated with various cutaneous diseases, including androgenic alopecia. However, their expression and role during the hair cycle are unknown. This study aims to investigate the expression of CXCL12 and its receptor, CXCR4, in the vicinity of hair follicles and their effect on hair growth. CXCL12 was highly expressed in dermal fibroblasts (DFs) and its level was elevated throughout the catagen and telogen phases of the hair cycle. CXCR4 is expressed in the dermal papilla (DP) and outer root sheath (ORS). In hair organ culture, hair loss was induced by recombinant CXCL12 therapy, which delayed the telogen-to-anagen transition and decreased hair length. In contrast, the suppression of CXCL12 using a neutralizing antibody and siRNA triggered the telogen-to-anagen transition and increased hair length in hair organ culture. Neutralization of CXCR7, one of the two receptors for CXCL12, only slightly affected hair growth. However, inhibition of CXCR4, the other receptor for CXCL12, increased hair growth to a considerable extent. In addition, in hair organ culture, the conditioned medium from DFs with CXCL12 siRNA considerably increased the hair length and induced proliferation of DP and ORS cells. CXCL12, through CXCR4 activation, increased STAT3 and STAT5 phosphorylation in DP and ORS cells. In contrast, blocking CXCL12 and CXCR4 decreased the phosphorylation of STAT3 and STAT5. In summary, these findings suggest that CXCL12 inhibits hair growth via the CXCR4/STAT signaling pathway and that CXCL12/CXCR4 pathway inhibitors are a promising treatment option for hair growth.