VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

Strengthening the cellular function of dermal fibroblasts and dermal papilla cells using nanovesicles extracted from stem cells using blue light-based photobiomodulation technology

Human dermal fibroblasts (hDFs) play a critical role in skin health by producing extracellular matrix (ECM) components essential for structural stability, while hair follicle dermal papilla cells (HFDPCs) are key to hair follicle growth and regeneration. However, factors such as UV radiation, oxidative stress, and aging impair the functions of hDFs and HFDPCs, leading to decrement in ECM production and skin maintenance and hair loss conditions like alopecia. Recent advances in nanovesicles (NVs) derived from human adipose-derived stem cells (hADSCs) have shown an innovative way in the regenerative medicine field, particularly with promise for enhancing the functionality of diverse cell types. NVs, filled with diverse bioactive molecules, are non-immunogenic, biologically stable, and capable of promoting cellular activities. To further enhance the therapeutic potential of NVs, photobiomodulation (PBM) using blue light has emerged as a promising application. Optimized blue light irradiation can induce moderate levels of reactive oxygen species production in hADSCs, activating signaling pathways that upregulate angiogenic and regenerative markers in hADSCs. In this study, blue light-irradiated NVs demonstrated superior efficacy in promoting hDF proliferation, ECM synthesis, and the functionality of HFDPCs, resulting in enhanced skin maintenance and hair follicle regeneration. This approach presents a safer and more efficient way for treating skin and hair disorders, highlighting the potential use of blue light-irradiated NVs as an innovative therapeutic strategy.

Co-delivery of minoxidil and finasteride via ionic liquid and cyclodextrin-assisted in situ thermosensitive hydrogel for synergistic treatment of androgenic alopecia

Androgenic alopecia (AGA), the most prevalent type of progressive hair loss, currently lacks an effective topical treatment regimen. In this study, we synthesized an ionic liquid (IL) to co-solubilize minoxidil (MXD) and finasteride (FIN) and subsequently formulated them into an in situ thermosensitive ionic liquid/cyclodextrin/poloxamer hydrogel (ICPG), termed M + F@ICPG. M + F@ICPG was developed for the transdermal co-delivery of these two drugs, aiming to provide a multipath therapeutic approach for AGA while avoiding the adverse effects commonly associated with oral FIN and topical MXD tincture. The thermosensitive characteristics, skin penetration, hair follicle (HF) targeting efficiency, biosafety, and in vivo therapeutic efficacy of M + F@ICPG were evaluated using an AGA mouse model. Our results demonstrated that M + F@ICPG was a thermosensitive hydrogel, transitioning from solution to gel upon contact with the scalp. Compared to the FIN suspension and MXD tincture, M + F@ICPG significantly enhanced the skin penetration (∼2.2-fold) and retention (∼8.6-fold) of FIN and increased the relative retention of MXD (∼6.3-fold) in the skin. Moreover, M + F@ICPG exhibited a HF targeting index of 1.74 for MXD and 1.46 for FIN, indicating enhanced drug targeting to HF. M + F@ICPG showed superior in vivo efficacy in terms of hair regeneration, anagen recovery, inflammation mitigation, and microvessel reconstruction. The underlying mechanism was attributed to the upregulation of hair growth genes, downregulation of hair loss genes, and reduction of abnormally elevated inflammatory factors. These findings suggest that this novel M + F@ICPG is a promising topical co-delivery system for the synergistic treatment of AGA.

5-Fluorouracil induces hair loss by inhibiting β-catenin signaling and angiogenesis

Chemotherapy-induced alopecia (CIA) is a side effect of the anticancer drug 5-fluorouracil (5-FU). However, the mechanism of action in hair follicle cells is unclear. This study investigated the mechanism of action of 5-FU on the hair cycle and growth in vitro and in vivo. Intraperitoneal injection of 5-FU into C57BL/6 mice delayed anagen initiation, resulting in small hair follicles. 5-FU inhibited angiogenesis by reducing cluster of differentiation 31+ cells, vascular endothelial growth factor, and fetal liver kinase-1 expression in mouse skin tissue and rat vibrissa dermal papilla (rDP) cells. 5-FU induced cell death in rDP cells and keratinocytes by enhancing cell cycle arrest or reducing the ratio of B-cell lymphoma 2 (Bcl-2) to Bcl-2-associated X levels. Immunoblotting and confocal microscopy showed that 5-FU inhibited the nuclear translocation of β-catenin in rDP cells and decreased fibroblast growth factor 7 and 10 secretion. Conversely, molecule-specific inhibitors did not prevent rDP cell death despite protein kinase B and Jun N-terminal kinase activation by 5-FU, indicating their indirect involvement. These results suggest that 5-FU inhibits wingless-related integration site/β-catenin signaling and angiogenesis, resulting in anagen-to-catagen transition and delaying anagen initiation. This study provides foundational data for developing treatments against CIA in patients with cancer undergoing 5-FU chemotherapy.

Novel strategy for hair regeneration: Exosomes and collagenous sequences of human a1(XVII) chain enhance hair follicle stem cell activity by regulating the hsa-novel-238a-CASP9 axis

The regenerative capacity of hair follicles is fundamentally influenced by the intricate interactions between hair follicle stem cells (HFSCs) and their microenvironment. Our study presents a novel strategy for hair regeneration, highlighting the synergistic relationship between dermal papilla cell-derived exosomes (DPC-Exos) and collagenous sequences of Human a1(XVII) Chain (CS-COL17A1) in modulating HFSC activity via the hsa-novel-238a-CASP9 axis. We characterized DPC-Exos using nanoparticle tracking analysis and transmission electron microscopy and confirmed, their purity with the exosomal markers CD81, CD63, and CD9.A dose-dependent CCK-8 assay showed that both DPC-Exos and CS-COL17A1 significantly improved HFSC viability. Scratch and Transwell assays showed improved HFSC migration after treatment. MiRNA sequencing revealed a significant upregulation of hsa-novel-238a in HFSCs after treatment with DPC-Exos and CS-COL17A1, suggesting its involvement in the regulation of HFSCs activity. A dual-luciferase assay confirmed that hsa-novel-238a directly targets the CASP9 gene, elucidating the underlying molecular mechanisms. The combined application of DPC-Exos and CS-COL17A1 significantly improved HFSC migration and proliferation (p < 0.01), highlighting the importance of the hsa-novel-238a-CASP9 axis. This research provides insights into the regulatory network of exosomes and CS-COL17A1, paving the way for innovative therapeutic approaches to treat hair loss and enhance hair follicle regeneration through modulation of the hsa-novel-238a-CASP9 axis.

Modulating metal-organic frameworks by surface engineering of stearic acid modification for follicular drug delivery and enhanced hair growth promotion

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.

N6-Methyladenosine (m6A)-Circular RNA Pappalysin 1 (circPAPPA) from Cashmere Goats: Identification, Regulatory Network and Expression Potentially Regulated by Methylation in Secondary Hair Follicles Within the First Intron of Its Host Gene

N6-methyladenosine (m6A) is one of the most abundant modifications in eukaryotic RNA molecules and mediates the functional exertion of RNA molecules. We characterized the circPAPPA and validated its potential m6A modification sites in secondary hair follicles (SHFs) of cashmere goats. Furthermore, we generated integrated regulatory networks of the circPAPPA along with enrichment analysis of signaling pathways. We also explored the potential relationship of circPAPPA expression with the first intron methylation of the PAPPA gene in SHFs of cashmere goats. Host source analysis revealed that circPAPPA is derived from the complete exon 2 of the PAPPA gene, spliced in reverse orientation, and predominantly localized in the cytoplasm of SHF stem cells in cashmere goats. The circPAPPA was verified to contain at least four m6A modification sites in SHFs of cashmere goats, including m6A-450/456, m6A-852, m6A-900, and m6A-963. The generated regulatory network indicated complex and diverse regulatory relationships of m6A-circPAPPA with its putative regulatory molecules, including miRNAs, mRNAs, and proteins. Enrichment analysis of signaling pathways showed that m6A-circPAPPA might play multiple functional roles in the growth and development of SHF in cashmere goats through the putative regulatory network mediated by its target miRNAs and regulatory proteins. The first intron methylation of the PAPPA gene most likely is significantly involved in the dynamic expression of m6A-circPAPPA in cashmere goat SHFs. Results from this study provided novel information to elucidate the biological roles and functional regulatory pathways of m6A-circPAPPA in SHF development and the growth of cashmere goat fiber.

Insights from Tandem Mass Tag (TMT) Proteomic Analysis on Protein Network Modification in Control of Yak Hair Follicle Cycle

Highland animals have unique hair growth mechanisms to allow them to adapt to harsh living environments. Compared with other species, their hair cycle growth is affected by more environmental factors. Yaks, as highland animals, have obvious periodic hair growth characteristics in a year; this biological process is regulated by numerous proteins, but the specific molecular regulatory mechanism is still unclear. Here we analyzed the histological characteristics of yak hair follicles (HFs) at each stage and conducted TMT proteomics research. The protein expression network of yak hair at each stage and the mechanism of the yak HF growth cycle were systematically explored, and the candidate proteins Sfrp1 and Ppard were verified. A total of 3176 proteins were quantifiable and 1142 differentially expressed proteins (DEPs) were obtained at five stages of the yak hair cycle. DEPs enriched in complement activation change, tissue development, lipid metabolism, WNT pathway, VEGF pathway, JAK-STAT pathway, and PPAR pathway may promote the growth of yak hair follicles, such as Serpinf1, Ppard, and Stat3. DEPs enriched in complement system, coagulation, cell adhesion, lipid metabolic process, proliferation of epidermal cells, and estrogen pathway may promote the degeneration of yak hair, such as Sfrp1, Eppk1, and Egfr. Using Protein-Protein Interaction (PPI) analysis, we found that core nodes of DEP networks in yak skin are significantly different at three critical time points in hair follicle development, and lipid metabolism proteins are common core DEP nodes during yak HF growth and degeneration. The expression of Sfrp1 and Ppard in yak hair follicles at different periods showed they are related to yak hair cycle control. This study showed that the protein regulatory network of the yak HF growth cycle is complex and dynamically changing and revealed key candidate proteins that may affect yak hair follicle development. These findings provided detailed data for further understanding of the plateau adaptation mechanism of the yak, which is of great significance to make better use of the yak livestock resources and enhance their economic value.

Is autologous platelet-rich plasma capable of increasing hair density in patients with androgenic alopecia? A systematic review and meta-analysis of randomized clinical trials

FUNDAMENTALS

Platelet-rich plasma (PRP) has been progressively more used in androgenetic alopecia (AGA).

OBJECTIVES

The authors aimed to evaluate PRP efficacy compared to placebo in AGA.

METHODS

A comprehensive search was conducted across seven databases, until 01/04/2023. Randomized clinical trials focusing on AGA and PRP use to increase hair density were included. Patients aged between 15 and 63 years, diagnosed with AGA characterized by Norwood I‒VII and Ludwig I‒III scales, were included. Studies with a sample size <10, lacking PRP processing method, focusing on complementary therapies or other alopecias, were excluded. The authors conducted subgroup analysis for activator, spin method, study design, risk of bias, and gender. Meta-regression was conducted for activator, spin method, design, and gender. The authors used GRADEpro to assess evidence certainty and the RoB-2 tool for risk of bias. Asymmetry was measured through a Funnel plot followed by Egger's test. The protocol was registered at PROSPERO (CRD42023407334).

RESULTS

The authors screened 555 registers and included fourteen studies involving 431 patients for qualitative synthesis, with 13 studies included in the meta-analysis. Meta-analysis demonstrated a mean difference of 27.55 hairs/cm2 and 95% CI (14.04; 41.06), I2 = 95.99%, p < 0.05. Hair diameter meta-analysis presented a mean difference of 2.02 μm, 95% CI (-0.85 μm; 4.88 μm), and I2 = 77.11% (p = 0.02). That is, low quality evidence.

STUDY LIMITATIONS

Studies were highly heterogeneous, of low quality, and presented evident publication bias.

CONCLUSIONS

Highly heterogeneous studies with publication bias suggest PRP effectively increases hair density in AGA, so further high-quality randomized clinical trials are recommended to strengthen the evidence.

Platycladus orientalis Leaf Extract Promotes Hair Growth via Non-Receptor Tyrosine Kinase ACK1 Activation

Platycladus orientalis is a traditional oriental herbal medicinal plant that is widely used as a component of complex prescriptions for alopecia treatment in Eastern Asia. The effect of PO on hair growth and its underlying mechanism, however, have not been demonstrated or clarified. In this study, we investigated the hair-growth-promoting effect of PO in cultured human dermal papilla cells (hDPCs). Platycladus orientalis leaf extract (POLE) was found to stimulate the proliferation of hDPCs. POLE with higher quercitrin concentration, especially, showed a high level of cellular viability. In the context of cellular senescence, POLE decreased the expression of p16 (CDKN2A) and p21(CDKN1A), which resulted in enhanced proliferation. In addition, growth factor receptors, FGFR1 and VEGFR2/3, and non-receptor tyrosine kinases, ACK1 and HCK, were significantly activated. In addition, LEF1, a transcription factor of Wnt/β-catenin signaling, was enhanced, but DKK1, an inhibitor of Wnt/β-catenin signaling, was downregulated by POLE treatment in cultured hDPCs. As a consequence, the expression of growth factors such as bFGF, KGF, and VEGF were also increased by POLE. We further investigated the hair-growth-promoting effect of topically administered POLE over a 12-week period. Our data suggest that POLE could support terminal hair growth by stimulating proliferation of DPCs and that enhanced production of growth factors, especially KGF, occurred as a result of tyrosine kinase ACK1 activation.

Irisin promotes hair growth and hair cycle transition by activating the GSK-3β/β-catenin pathway

Hair loss affects men and women of all ages. Myokines, which are mainly secreted by skeletal muscles during exercise, have numerous health benefits. VEGF, IGF-1, FGF and irisin are reprehensive myokines. Although VEGF, IGF-1 and FGF are positively associated with hair growth, few studies have researched the effects of irisin on hair growth. Here, we investigated whether irisin promotes hair growth using in vitro, ex vivo and in vivo patch assays, as well as mouse models. We show that irisin increases proliferation, alkaline phosphatase (ALP) activity and mitochondrial membrane potential in human dermal papilla cells (hDPCs). Irisin activated the Wnt/β-catenin signalling pathway, thereby upregulating Wnt5a, Wnt10b and LEF-1, which play an important role in hair growth. Moreover, irisin enhanced human hair shaft elongation. In vivo, patch assays revealed that irisin promotes the generation of new hair follicles, accelerates entry into the anagen phase, and significantly increases hair growth in C57BL/6 mice. However, XAV939, a Wnt/β-catenin signalling inhibitor, suppressed the irisin-mediated increase in hair shaft and hair growth. These results indicate that irisin increases hair growth via the Wnt/β-catenin pathway and highlight its therapeutic potential in hair loss treatment.

Can Plant Extracts Help Prevent Hair Loss or Promote Hair Growth? A Review Comparing Their Therapeutic Efficacies, Phytochemical Components, and Modulatory Targets

This narrative review aims to examine the therapeutic potential and mechanism of action of plant extracts in preventing and treating alopecia (baldness). We searched and selected research papers on plant extracts related to hair loss, hair growth, or hair regrowth, and comprehensively compared the therapeutic efficacies, phytochemical components, and modulatory targets of plant extracts. These studies showed that various plant extracts increased the survival and proliferation of dermal papilla cells in vitro, enhanced cell proliferation and hair growth in hair follicles ex vivo, and promoted hair growth or regrowth in animal models in vivo. The hair growth-promoting efficacy of several plant extracts was verified in clinical trials. Some phenolic compounds, terpenes and terpenoids, sulfur-containing compounds, and fatty acids were identified as active compounds contained in plant extracts. The pharmacological effects of plant extracts and their active compounds were associated with the promotion of cell survival, cell proliferation, or cell cycle progression, and the upregulation of several growth factors, such as IGF-1, VEGF, HGF, and KGF (FGF-7), leading to the induction and extension of the anagen phase in the hair cycle. Those effects were also associated with the alleviation of oxidative stress, inflammatory response, cellular senescence, or apoptosis, and the downregulation of male hormones and their receptors, preventing the entry into the telogen phase in the hair cycle. Several active plant extracts and phytochemicals stimulated the signaling pathways mediated by protein kinase B (PKB, also called AKT), extracellular signal-regulated kinases (ERK), Wingless and Int-1 (WNT), or sonic hedgehog (SHH), while suppressing other cell signaling pathways mediated by transforming growth factor (TGF)-β or bone morphogenetic protein (BMP). Thus, well-selected plant extracts and their active compounds can have beneficial effects on hair health. It is proposed that the discovery of phytochemicals targeting the aforementioned cellular events and cell signaling pathways will facilitate the development of new targeted therapies for alopecia.

Synergistic treatment of androgenetic alopecia with follicular co-delivery of minoxidil and cedrol in metal-organic frameworks stabilized by covalently cross-linked cyclodextrins

Androgenetic alopecia seriously affects the physical and mental health of patients. The main clinical therapeutic agent, minoxidil tincture, is challenged by solvent irritation and dose-dependent side effects. Our recent work has identified a biosafety natural product, cedrol, that is synergistic in combination with minoxidil, thereby improving medication safety by substantially reducing the clinical dose of minoxidil. In addition, ccross-linked CD-MOF were designed as carriers for hair follicle delivery, and γ-CD in the carriers was cross-linked by diphenyl carbonate with covalent bonds to protect the CD-MOF from rapid disintegration in an aqueous environment. This improved nanocarrier has a drug loading of 25%, whereas nanocarriers increased drug delivery to the hair follicles through ratchet effect, and increased human dermal papilla cells uptake of drugs via endocytosis pathways mainly mediated by lattice proteins, energy-dependent active transport, and lipid raft-dependent, thus improved cell viability, proliferation, and migration, followed by significantly enhancing the anti-androgenetic alopecia effect, with cedrol focusing on inhibiting 5α-reductase and activating Shh/Gli pathway, and minoxidil, which up-regulated VEGF, down-regulated TGF-β, and activated ERK/AKT pathway. This drug combination provides a new therapeutic strategy for androgenetic alopecia, while the newly developed cross-linked CD-MOF has been shown to serve as a promising follicular delivery vehicle.

Screening of hair follicle telogen-associated circRNAs in sheep and construction of their ceRNA network

Sheep breeds with hair-shedding traits have many advantages over non-shedding sheep breeds, not only because of reduced shearing labor and feeding management costs but also because it reduces in vitro parasites and improves adaptability to summer heat stress. The wool of Dorper sheep naturally sheds in spring due to the periodic growth of hair follicles. CircRNAs primarily regulate the morphogenesis of hair follicles through the ceRNA mechanism. In this study, five 2-year-old Dorper ewes with extreme hair-shedding phenotype (S) and three Dorper ewes with non-shedding (N) phenotype were selected for subsequent analyses. For RNA extraction, skin tissues were collected on 27th September 2019 (S1, N1), 3rd January 2020 (S2, N2), and 17th March 2020 (S3, N3), which were then subjected to RNA-seq. RNA-seq technology revealed 20,185 novel circRNAs in the hair follicles of Dorper sheep. Among them, 1450 circRNAs were differentially expressed (DE). Clustering heatmap and expression pattern analyses were performed on DE circRNAs, which indicated 78 circRNAs with T pattern (Telogen, highly expressed in telogen), and the source genes for candidate circRNAs were further screened by functional enrichment analysis, which identified 13 crucial genes enriched in pathways associated with hair follicle development. Additionally, a ceRNA regulatory network comprising 4 circRNAs, 11 miRNAs, and 13 target genes was constructed. Overall, this study screened circRNAs that may be associated with the telogen phase of hair follicles in sheep, providing a relevant theoretical basis for wool shedding in sheep and for breeding Dorper sheep with automatic wool shedding.

Evaluation of efficacy of Silybum marianum flower extract on the mitigating hair loss in vitro and in vivo

BACKGROUND

Natural components that can exert a wide range of anti-hair loss activity with fewer side effects are in high demand. The objective of this study was to investigate the anti-hair loss potential of Silybum marianum flower extract (SMFE) in vitro and in vivo.

METHODS

The effect of SMFE on dermal papilla cells was evaluated by measuring cell proliferation and VEGF production in hair follicle dermal papilla cells (HFDPCs). In addition, to confirm the effect of SMFE on dermal papilla senescence, SA-β-gal staining and senescence associated secretory phenotype (SASP) production such as IL-6 was observed in both replicative and hydrogen peroxide (H2 O2 )-induced senescence models. In a clinical study, hair growth was determined by reconstitution analysis after shaving the hair of the clinical subject's scalp and hair area.

RESULTS

SMFE increased the proliferation and VEGF production of HFDPCs. It also suppressed cellular senescence of HFDPCs and IL-6 production in replicative senescence and oxidative stress-induced senescence models. The hair density and total hair count at 16 and 24 weeks after using hair shampoo containing SMFE were significantly increased compared with those of the placebo group.

CONCLUSION

SMFE has the potential to be used as a natural ingredient for alleviating hair loss.

Minoxidil delivered via a stem cell membrane delivery controlled release system promotes hair growth in C57BL/6J mice

Objective: Umbilical cord-derived mesenchymal stem cell membrane-loaded minoxidil (MXD) nanoparticles (STCM-MXD-NPs) were prepared to investigate their effects on hair growth in C57BL/6J mice. Methods: STCM-MXD-NPs were obtained by freeze-thawing and differential centrifugation, and their effects on hair growth were evaluated using C57BL/6J mice. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) were detected by real-time polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Protein expression levels of marker of proliferation Ki-67 (MKI67) and β-catenin (CTNNB) in skin tissue were detected by immunohistochemistry. Results: STCM-MXD-NPs improved MXD solubility. They released the drug slowly, increasing its transdermal properties, accumulation in the skin, and content in the hair bulb tissues with a better efficacy than that of ordinary MXD. Moreover, STCM-MXD-NPs significantly upregulated the mRNA and protein levels of VEGF and IGF-1 and promoted the protein expression of MKI67 and CTNNB in mouse skin tissues, promoting mouse hair growth. Conclusion: Stem cell membrane-loaded MXD nanoparticles with slow-release properties increased MXD accumulation in the skin by improving its transdermal properties, increasing VEGF, IGF-1, MKI67, and CTNNB expression levels and promoting hair growth in C57BL/6J mice.

Treatment of androgenetic alopecia by exosomes secreted from hair papilla cells and the intervention effect of LTF

BACKGROUND

Androgenetic alopecia (AGA) is the most common cause of chronic progressive hair loss in men, and AGA has a severe negative impact on the quality of life and physical and mental health of patients.

METHODS

Four female C57BL/6 mice were isolated from DP cells in culture (≤4 generations) after stimulation of DPC proliferation by herbal concentrations obtained by the CCK-8 method, and exosomes were isolated by differential centrifugation at low temperature. Testosterone propionate and topical hair removal treatments were used together to establish the C57BL/6 mouse AGA model, which was treated with LTF, 5% minoxidil, and LTF-DPC-EXO, respectively. ELISA was used to detect serum hormone levels, in vivo tracing was used to observe dynamic changes in exosomes, H&E staining showed changes in mouse hair follicle tissue, and (q) RT-PCR and WB were used to detect dorsal skin VEGF, AKT1, and CASP3 expression in dorsal skin tissues.

RESULTS

Hair regeneration was significant in the LTF group, minoxidil group, and LTF-DPC-EXO group mice, and the hair growth was only seen in the local skin in the model group. The hormone T in all treatment groups was lower than that in the model group, and e2 was higher than that in the model group. (q) RT-PCR and western blot showed that VEGF and AKT1 expressions were upregulated and Caspase3 expression was downregulated in the skin sections of mice in the treatment groups.

CONCLUSION

DPC-EXO obtained through LTF may activate AKT1 and VEGF in the PI3K/AKT signaling pathway to inhibit CASP3, thereby protecting DPC to restore the hair growth.

N,N-Dimethylglycine Sodium Salt Exerts Marked Anti-Inflammatory Effects in Various Dermatitis Models and Activates Human Epidermal Keratinocytes by Increasing Proliferation, Migration, and Growth Factor Release

N,N-dimethylglycine (DMG) is a naturally occurring compound being widely used as an oral supplement to improve growth and physical performance. Thus far, its effects on human skin have not been described in the literature. For the first time, we show that N,N-dimethylglycine sodium salt (DMG-Na) promoted the proliferation of cultured human epidermal HaCaT keratinocytes. Even at high doses, DMG-Na did not compromise the cellular viability of these cells. In a scratch wound-closure assay, DMG-Na augmented the rate of wound closure, demonstrating that it promotes keratinocyte migration. Further, DMG-Na treatment of the cells resulted in the upregulation of the synthesis and release of specific growth factors. Intriguingly, DMG-Na also exerted robust anti-inflammatory and antioxidant effects, as assessed in three different models of human keratinocytes, mimicking microbial and allergic contact dermatitis as well as psoriasis and UVB irradiation-induced solar dermatitis. These results identify DMG-Na as a highly promising novel active compound to promote epidermal proliferation, regeneration, and repair, and to exert protective functions. Further preclinical and clinical studies are under investigation to prove the seminal impact of topically applied DMG-Na on relevant conditions of the skin and its appendages.

Hypoxia Treatment of Adipose Mesenchymal Stem Cells Promotes the Growth of Dermal Papilla Cells via HIF-1α and ERK1/2 Signaling Pathways

Dermal papilla cells (DPCs) cultured in vitro induce hair follicle formation. Using a hypoxic microenvironment to culture adipose mesenchymal stem cells (ADSCs) can promote hair follicle growth. However, the exact molecular mechanisms underlying this process remain unclear. In this study, ADSCs and DPCs from Arbas Cashmere goats were used. A hypoxic microenvironment promoted the proliferation of ADSCs and increased the pluripotency of ADSCs. The growth factors vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and platelet-derived growth factor (PDGF) were upregulated in ADSCs in the hypoxia-conditioned medium (Hypo-cm). Hypo-cm also enhanced the ability of DPCs to induce hair follicle formation. Inhibitors of the ERK1/2 signaling pathway caused the expressions of growth factors that increased in hypoxic microenvironments to decrease; moreover, hypoxia-inducible factor-1α (HIF-1α) increased the expression levels of VEGF, bFGF, and PDGF and inhibited the expression of bone morphogenic protein 7 (BMP7). In conclusion, these findings improve the theoretical basis for the development of gene therapy drugs for the treatment of alopecia areata and hair thinning.

Garlic Exosomes Promote Hair Growth Through the Wnt/β-catenin Pathway and Growth Factors

Background Exosomes are membrane-derived nanovesicles produced by cells and play an important role in intercellular communication. Objectives This study aimed to investigate the effects of garlic exosome (GE) on hair growth. Methods Forty-two Sprague-Dawley/Wistar albino rats were randomly divided into six groups: non-shaved control, shaved control, topical control, GE 2 mg, GE 4 mg, and topical GE. At the end of the experiment, the number of hair follicles, follicle diameter, and subcutaneous tissue thicknesses were measured histopathologically. The Wnt-1, β-catenin, platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1), and collagen I levels were measured by the Western Blot method. Results The anagen follicle counts of the GE 2 mg, 4 mg, and topical GE groups were 66.57±15.49, 105.71±25.06, and 55.29±6.72, and were significantly higher than the control groups (p<0.01, p<0.001 and p<0.05, respectively). The follicle diameter of the GE 4 mg group was higher than the others (p<0.05). The Wnt-1, PDGF, VEGF, TGF-β1, and collagen I levels of all GE groups, and the β-catenin levels of the GE 4 mg and topical GE groups were significantly higher than the control groups (p<0.05). Conclusion GE induces hair growth in rats via the Wnt-1, β-catenin, VEGF, PDGF, and TGF-β1 signaling pathways.

Cedrol-loaded dissolvable microneedles based on flexible backing for promoting hair growth

OBJECTIVES

The dissolvable microneedles loaded with cedrol based on flexible backing were developed to deliver cedrol directly and continuously to the dermis, where the drug concentration in the hair follicle can be increased locally.

METHODS

The tip-layer matrix solution was prepared by mixing cedrol and polyvinylpyrrolidone K25 (PVP K25), and the pedestal matrix solution was prepared with aqueous hyaluronic acid. The cedrol-loaded dissolvable microneedles (cedrol-DMNs) were prepared under vacuum conditions. The mechanical properties, pig skin penetration efficiency, in vitro cutaneous permeation test, and the amount of drug in the skin and receptor chamber were evaluated. Pharmacodynamical studies were performed with C57BL/6 mice.

RESULTS

The mechanical properties of cedrol-DMNs were good. In vitro cutaneous permeation tests and pharmacodynamical studies demonstrated that cedrol-DMN could efficiently deliver the drug to the deep dermis and effectively promote hair growth.

CONCLUSIONS

The cedrol-DMNs offer a promising strategy for treating patients suffering from hair loss.

Effects of Allium hookeri Extracts on Hair-Inductive and Anti-Oxidative Properties in Human Dermal Papilla Cells

Oxidative stress and cellular senescence in dermal papilla cells (DPCs) are major etiological factors causing hair loss. In this study, the effect of the Allium hookeri extract (AHE) on hair-inductive and anti-oxidative properties was investigated in human DPCs. As a result, it was found that a non-cytotoxic concentration of the extracts increased the viability and size of the human DPC spheroid, which was associated with the increased expression of hair-growth-related genes in cells. To determine whether or not these effects could be attributed to intracellular anti-oxidative effects, liquid chromatography-mass spectrometry alongside various biochemical analyses are conducted herein. An ingredient called alliin was identified as one of the main components. Furthermore, AHE treatment induced a significant decrease in H₂O₂-mediated cytotoxicities, cell death, and cellular senescence in human DPCs. Upon analyzing these results with a molecular mechanism approach, it was shown that AHE treatment increased β-Catenin and NRF2 translocation into the nucleus while inhibiting the translocation of NF-κB (p50) through p38 and PKA-mediated phosphorylations of GSK3β, an upstream regulator of those proteins. These results overall indicate the possibility that AHE can regulate GSK3β-mediated β-Catenin, NRF2, and NF-κB signaling to enhance hair-inductive properties and ultimately protect against oxidative stress-induced cellular damage in human DPCs.

Hair Follicle Transcriptome Analysis Reveals Differentially Expressed Genes That Regulate Wool Fiber Diameter in Angora Rabbits

Wool fiber diameter (WFD) is an important index of wool traits and the main determinant of wool quality and value. However, the genetic determinants of fiber diameter have not yet been fully elucidated. Here, coarse and fine wool of Wan strain Angora rabbits and their hair follicle traits were characterized. The results indicated significant differences in the diameters of wool fibers and their hair follicles. The RNA sequencing (RNA-Seq) technique was used to identify differences in gene expression in hair follicles between coarse and fine wool. In total, 2574 differentially expressed genes (DEGs) were found between the two hair follicle groups. Transcription factors, keratin-associated protein (KAP) and keratin (KRT) families, and ECM-related genes may control the structure of fine fibers in rabbits. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that skin development, epidermal cell and keratinocyte differentiation, epithelium development, and Notch and ribosome signaling pathways were significantly enriched, respectively. GSEA further filtered six important pathways and related core genes. PPI analysis also mined functional DEGs associated with hair structure, including LEF1, FZD3, SMAD3, ITGB6, and BMP4. Our findings provide valuable information for researching the molecular mechanisms regulating wool fiber and could facilitate enhanced selection of super-fine wool rabbits through gene-assisted selection in the future.

Limonin, a Component of Immature Citrus Fruits, Activates Anagen Signaling in Dermal Papilla Cells

Hair loss remains a significant problem that is difficult to treat; therefore, there is a need to identify safe natural materials that can help patients with hair loss. We evaluated the hair anagen activation effects of limonin, which is abundant in immature citrus fruits. Limonin increased the proliferation of rat dermal papilla cells (rDPC) by changing the levels of cyclin D1 and p27, and increasing the number of BrdU-positive cells. Limonin increased autophagy by decreasing phosphorylated mammalian target of rapamycin levels and increasing the phospho-Raptor, ATG7 and LC3B. Limonin also activated the Wnt/β-catenin pathway by increasing phospho-β-catenin levels. XAV939, a Wnt/β-catenin inhibitor, inhibited these limonin-induced changes, including induced autophagy, BrdU-positive cells, and cell proliferation. Limonin increased the phosphorylated AKT levels in both two-dimensional cultured rDPC and three-dimensional spheroids. Treatment with the PI3K inhibitor wortmannin inhibited limonin-induced proliferation, and disrupted other limonin-mediated changes, including decreased p27, increased BrdU-positive cells, induced autophagy, and increased ATG7 and LC3B levels. Wortmannin also inhibited limonin-induced cyclin D1 and LC3 expression in spheroids. Collectively, these results indicate that limonin can enhance anagen signaling by activating autophagy via targeting the Wnt/β-catenin and/or PI3K/AKT pathways in rDPC, highlighting a candidate nutrient for hair loss treatment.

Engineered Nanovesicles from Fibroblasts Modulate Dermal Papillae Cells In Vitro and Promote Human Hair Follicle Growth Ex Vivo

Alopecia is a common medical condition affecting both sexes. Dermal papilla (DP) cells are the primary source of hair regeneration in alopecia patients. Therapeutic applications of extracellular vesicles (EVs) are restricted by low yields, high costs, and their time-consuming collection process. Thus, engineered nanovesicles (eNVs) have emerged as suitable therapeutic biomaterials in translational medicine. We isolated eNVs by the serial extrusion of fibroblasts (FBs) using polycarbonate membrane filters and serial and ultracentrifugation. We studied the internalization, proliferation, and migration of human DP cells in the presence and absence of FB-eNVs. The therapeutic potential of FB-eNVs was studied on ex vivo organ cultures of human hair follicles (HFs) from three human participants. FB-eNVs (2.5, 5, 7.5, and 10 µg/mL) significantly enhanced DP cell proliferation, with the maximum effect observed at 7.5 µg/mL. FB-eNVs (5 and 10 µg/mL) significantly enhanced the migration of DP cells at 36 h. Western blotting results suggested that FB-eNVs contain vascular endothelial growth factor (VEGF)-a. FB-eNV treatment increased the levels of PCNA, pAKT, pERK, and VEGF-receptor-2 (VEGFR2) in DP cells. Moreover, FB-eNVs increased the human HF shaft size in a short duration ex vivo. Altogether, FB-eNVs are promising therapeutic candidates for alopecia.

Sodium pentaborate pentahydrate promotes hair growth through the Wnt/β-catenin pathway and growth factors

BACKGROUND

Boron (B) is an element involved in many physiological processes in humans and accelerates wound healing and increases angiogenesis. This study aimed to evaluate the possible effects of sodium pentaborate pentahydrate (NaB) on hair growth and reveal its effects on Wnt-1, β-catenin, vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and transforming growth factor-β1 (TGF-β1) signaling pathways, which are important molecular mechanisms involved in hair growth.

METHODS

Thirty-five Sprague-Dawley/Wistar albino rats were randomly divided into five groups: non-shaved control, shaved control, NaB 1 mg (shaved + NaB 1 mg elemental B/kg CA), NaB 2 mg (shaved + NaB 2 mg elemental B/kg CA), and NaB 4 mg (shaved + NaB 4 mg elemental B/kg CA). Hair density was measured using the trichoscopy method. Dorsal skin samples were examined histopathologically at the end of the 42nd day, and follicle count, follicle diameter, and subcutaneous tissue thickness were recorded. Wnt-1, β-catenin, PDGF, VEGF, TGF-β_1, and collagen I levels were analyzed with the Western blot method.

RESULTS

In trichoscopy measurements, hair density increased in the NaB 4 mg group (90.9%). In histopathological examination, anagen follicles were observed to increase in the NaB 1 mg and 2 mg groups (p < 0.05). Follicle diameter increased in all NaB groups (p < 0.05). The Wnt-1, β-catenin, PDGF, VEGF, TGF-β₁, and collagen I level increased in the NaB 1 mg and 2 mg groups (p < 0.05), but they were similar in the NaB 4 mg group compared to the control groups (p > 0.05).

CONCLUSION

NaB 1 and 2 mg B/kg supplementation induces the anagen phase in rats via Wnt-1, β-catenin, VEGF, PDGF, and TGF-β1 signaling pathways. NaB 4 mg B/kg suppresses these pathways and adversely affects hair growth.

Activation of cAMP Signaling in Response to α-Phellandrene Promotes Vascular Endothelial Growth Factor Levels and Proliferation in Human Dermal Papilla Cells

Dermal papilla cells (DPCs) are growth factor reservoirs that are specialized for hair morphogenesis and regeneration. Due to their essential role in hair growth, DPCs are commonly used as an in vitro model to investigate the effects of hair growth-regulating compounds and their molecular mechanisms of action. Cyclic adenosine monophosphate (cAMP), an intracellular second messenger, is currently employed as a growth-promoting target molecule. In a pilot test, we found that α-phellandrene, a naturally occurring phytochemical, increased cAMP levels in DPCs. Therefore, we sought to determine whether α-phellandrene increases growth factors and proliferation in human DPCs and to identify the underlying mechanisms. We demonstrated that α-phellandrene promotes cell proliferation concentration-dependently. In addition, it increases the cAMP downstream effectors, such as protein kinase A catalytic subunit (PKA Cα) and phosphorylated cAMP-responsive element-binding protein (CREB). Also, among the CREB-dependent growth factor candidates, we identified that α-phellandrene selectively upregulated vascular endothelial growth factor (VEGF) mRNA expression in DPCs. Notably, the beneficial effects of α-phellandrene were nullified by a cAMP inhibitor. This study demonstrated the cAMP-mediated growth effects in DPCs and the therapeutic potential of α-phellandrene for preventing hair loss.

Efficacy and safety of apatinib monotherapy for patients with advanced breast cancer: a systematic review and meta-analysis

Background

Patients with advanced breast cancer usually have poor prognosis. Apatinib is a small-molecule tyrosine kinase inhibitor, and the reports regarding the efficacy and safety of apatinib monotherapy for advanced breast cancer in the current literature are controversial. Therefore, we performed a systematic review and meta-analysis to collect and pool efficacy and safety data of apatinib monotherapy for advanced breast cancer with the aim of providing up-to-date evidence to aid clinical practice.

Methods

This study was registered at PROSPERO (CRD42020190049). Three literature databases, including PubMed, EMBASE, and Cochrane Library, were searched. For evaluating efficacy, the objective response rate and disease control rate were extracted or calculated. Safety was evaluated in terms of the proportions of patients with grade 3 or 4 treatment-related adverse events. The pooled proportions of the outcomes and their 95% confidence interval were shown. The Kaplan–Meier curves of overall survival and progression-free survival were pooled from the extracted data of the included studies. Furthermore, pooled medians for overall survival and progression-free survival were calculated. A p-value of &lt; 0.05 was considered statistically significant.

Results

Six studies were included and deemed eligible for further quality evaluation and analysis. The pooled objective response rate and disease control rate were 20.4% and 71.6%, respectively. The pooled proportions of four hematologic adverse events ranged from 2.6% to 6.9%. The pooled proportions of hypertension, hand-foot syndrome, transaminase increased, and proteinuria ranged from 4.1% to 24.3%, and other non-hematologic adverse events were &lt;1%. The pooled median progression-free survival and overall survival were 4.00 and 10.43 months, respectively, in cases of advanced breast cancer treated with apatinib.

Conclusions

This study confirms the reliable efficacy of apatinib monotherapy for advanced breast cancer. However, non-hematologic grade 3–4 adverse events, especially hypertension, are more frequently observed during apatinib treatment than during treatment with other tyrosine kinase inhibitors, such as sunitinib or sorafenib.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020190049.

Preparation and characterization of novel lithium magnesium phosphate bioceramic scaffolds facilitating bone generation

Both magnesium and lithium are able to stimulate osteogenic and angiogenic activities. In this study, lithium magnesium phosphate (Li_0.5Mg_2.75(PO₄)₂, Li₁Mg_2.5(PO₄)₂ and Li₂Mg₂(PO₄)₂) biomaterials were synthesized by a solid-state reaction method, and their bioceramic blocks and scaffolds were fabricated by compression molding and 3D printing, respectively. The results indicated that the lithium magnesium phosphates consisted of the Mg₃(PO₄)₂ phase and/or LiMgPO₄ phase. Compared with the lithium-free Mg₃(PO₄)₂ bioceramics, the lithium magnesium phosphate bioceramics showed a lower porosity and consequently a higher compressive strength, and stimulated in vitro cellular proliferation, osteogenic differentiation and proangiogenic activity. In vivo results manifested that the Li₂Mg₂(PO₄)₂ bioceramic scaffolds efficiently promoted bone regeneration of critical-size calvarial defects in rats. Benefiting from the high compressive strength and capacity of stimulating osteogenesis and angiogenesis, the Li₂Mg₂(PO₄)₂ bioceramic scaffolds are considered promising for efficiently repairing the bone defects.

Epithelial-Mesenchymal Interaction in Hair Regeneration and Skin Wound Healing

Interactions between epithelial and mesenchymal cells influence hair follicles (HFs) during embryonic development and skin regeneration following injury. Exchanging soluble molecules, altering key pathways, and extracellular matrix signal transduction are all part of the interplay between epithelial and mesenchymal cells. In brief, the mesenchyme contains dermal papilla cells, while the hair matrix cells and outer root sheath represent the epithelial cells. This study summarizes typical epithelial–mesenchymal signaling molecules and extracellular components under the control of follicular stem cells, aiming to broaden our current understanding of epithelial–mesenchymal interaction mechanisms in HF regeneration and skin wound healing.

Integrative analysis of circRNAs from Yangtze River Delta white goat neck skin tissue by high-throughput sequencing (circRNA-seq)

The Yangtze River Delta white goat is a unique goat species that can produce superior-quality brush hair. The formation of this brush hair is controlled by a series of critical genes and related signaling pathways. Circular RNAs (circRNAs), are ubiquitous endogenous non-coding RNAs that regulate many biological and physiological processes in mammals. However, little is known about the potential regulatory role of circRNAs on superior-quality brush hair formation in Yangtze River Delta white goat. In this study, high-throughput sequencing technology was used to only detect circRNAs in the neck skin tissue of normal-quality goats (NHQs) and superior-quality goats (HQs). A total of 61 803 circRNAs were identified and 32 of them were differentially expressed in the NHQ group vs. the HQ group. Functional enrichment analysis showed that the source gene of differentially expressed circRNAs (DE-circRNAs) was enriched mostly in platelet activation and the focal adhesion signal pathway. Action mechanism analysis revealed that DE-circRNAs could sponge to many identified miRNAs, including miR-31, miR-125b, miR-let-7a and miR-149-5p, which have important roles in goat hair follicle stem cell growth, hair follicle development and morphogenesis. Altogether, our findings provide a valuable basis for studying circRNAs involved in superior-quality brush hair traits and meanwhile advance our understanding of circRNA complex regulation mechanisms in Yangtze River Delta white goat skin hair follicle development.

Whole-genome resequencing of worldwide wild and domestic sheep elucidates genetic diversity, introgression and agronomically important loci

Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (∼16.10×) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ∼121.2 million single nucleotide polymorphisms, ∼61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 3′-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep.

Dexpanthenol Promotes Cell Growth by Preventing Cell Senescence and Apoptosis in Cultured Human Hair Follicle Cells

Dexpanthenol (D-panthenol) is a precursor of vitamin B5 (pantothenic acid) and is widely used for dietary supplements and topical applications. D-panthenol has long been used in hair care products for the purpose of anti-hair loss, its effects and the underlying mechanisms, however, were barely reported. In this study, the effects of D-panthenol on human hair follicle cells, including dermal papilla cells (hDPCs) and outer root sheath cells (hORSCs), were investigated. D-panthenol enhanced the cell viability, increasing the cellular proliferation marker Ki67 in cultured hDPCs. The markers for apoptosis (Caspase3/9) and cell senescence (p21/p16), reported to be expressed in aged or resting phase follicles, were significantly reduced by D-panthenol. Anagen-inducing factors (ALP; β-catenin; versican), which trigger or elongate the anagen phase, were stimulated by D-panthenol. On the other hand, D-panthenol reduced TGF-β1 expressions in both mRNA and protein levels. The expression of VEGF, which is important for peripheral blood vessel activation; was up-regulated by D-panthenol treatment. In cultured hORSCs, cell proliferation and viability were enhanced, while the mRNA expression of cell senescence markers (p21/p16) was significantly down-regulated. The expressions of both VEGF and its receptor (VEGFR) were up-regulated by D-panthenol. In conclusion, our data suggest that the hair growth stimulating activity of D-panthenol was exerted by increasing the cell viability, suppressing the apoptotic markers, and elongating the anagen phase in hair follicles.

Hair growth-promotion effects at the cellular level and antioxidant activity of the plant-based extract Phyllotex™

Hair loss and predominantly female hair loss is a common dermatologic condition with serious psychosocial consequences. Effective treatments remain scarce mainly due to the multifactorial elements involved in the onset of this chronic condition. The approved drugs available are based on molecules designed towards a single pharmacological target and do not interact with the various biochemical mechanisms involved in alopecia. Phytochemical compounds and their derivatives represent a plethora of biologically active agents, which act in synergism and simultaneously activate different biochemical pathways. Here we present an herbal formulation composed of herbs, vitamins, and minerals acting on hair regrowth and hair micro vascularization.

This study aimed at evaluating the potential of Phyllotex™ to treat multifactorial androgenetic alopecia (AGA) in males and females, as well as delving into its molecular mechanisms of action. In vitro studies showed that the herbal formula stimulates cell proliferation of both dermal papilla and HaCaT cells and increases the phosphorylated form of the extracellular signal-regulated kinase 1 and 2 (ERK1/2), a well-known marker for cell proliferation. Surprisingly, expression of TGF-β1 was significantly suppressed without blocking DHT production. Additionally, the formula was able to rescue cells from the oxidative stress conditions generated by 2,2′-Azobis (2-amidinopropane) dihydrochloride (AAPH), a high oxidative agent. This data supports the potential use of this formulation as a hair growth-promoting agent for the treatment of both male and female AGA due to its multifactorial composition, which grants it the ability to cope with the different mechanisms involved in alopecia.

Lactobacillus paracasei HY7015 Promotes Hair Growth in a Telogenic Mouse Model

In this study, we describe the effects of Lactobacillus paracasei HY7015 (HY7015) on promoting mouse hair growth. Since our purpose was to increase hair growth through oral administration, medicinal yeast, at a suitable concentration for application in mice, was used as a positive control. First, experiments were conducted to determine the effect of HY7015 on proliferation of hair follicle dermal papilla cells (HFDPC), which are important contributors to hair growth. HY7015 stimulated HFDPC proliferation in vitro and increased their secretion of vascular endothelial growth factor and insulin-like growth factor-1. In mouse experiments, oral administration of HY7015 promoted hair growth and hair follicle maturation in the dorsal skin, as well as increasing growth factor levels in mouse serum. In summary, we demonstrate that L. paracasei HY7015 consumption can promote hair growth by stimulating HFDPC proliferation and growth factor secretion. Follow-up studies are warranted to determine the underlying mechanism, using various approaches, including investigation of changes in intestinal microbiota and alteration of gene and protein expression.

Hair Growth Promoting Activity of Cedrol Nanoemulsion in C57BL/6 Mice and Its Bioavailability

As the main component of Platycladus orientalis, cedrol has known germinal activity. A range of cedrol formulations have been developed to prevent hair-loss, but compliance remains key issues. In this study, we prepared cedrol nanoemulsion (CE-NE) and determined the particle size and PDI (polydispersion coefficient), investigated the hair growth activity and studied the bioavailability in vitro and in vivo. Results showed that the average particle size of CE-NE is 14.26 ± 0.16 nm, and the PDI value is 0.086 ± 0.019. In vitro drug release investigation and drug release kinetics analysis showed release profile of CE from nanoparticles demonstrates the preferred partition of CE in buffer pH 4.0, the release profile of CE-NE showed a first-order kinetics reaching around 36.7% after 6 h at 37 °C. We artificially depilated the back hair of C57BL/6 mice and compared the efficacy of a designed cedrol nanoemulsion to an existing ointment group. The hair follicles were imaged and quantified using a digital photomicrograph. The results showed that compared with the ointment, CE-NE had positive effects on hair growth, improved drug solubility. Compared with the ointment and 2% minoxidil groups, 50 mg/mL CE-NE led to more robust hair growth. Pharmacokinetics analysis showed that the AUC0-t of CE-NE was 4-fold higher than that of the ointment group, confirming that the bioavailability of the nanoemulsion was greater than that of the ointment. CE-NE also significantly reduced the hair growth time of model mice and significantly increased the growth rate of hair follicles. In conclusion, these data suggest that the nanoemulsion significantly improved the pharmacokinetic properties and hair growth effects cedrol, enhancing its efficacy in vitro and in vivo.

Generation of VEGF knock-in Cashmere goat via the CRISPR/Cas9 system

Cashmere is a rare and specialised animal fibre, which grows on the outer skin of goats. Owing its low yield and soft, light, and warm properties, it has a high economic value. Here, we attempted to improve existing cashmere goat breeds by simultaneously increasing their fibre length and cashmere yield. We attempted this by knocking in the vascular endothelial growth factor (VEGF) at the fibroblast growth factor 5(FGF5) site using a gene editing technology and then studying its hair growth-promoting mechanisms. We show that a combination of RS-1 and NU7441 significantly improve the efficiency of CRISPR/Cas9-mediated, homologous-directed repair without affecting the embryo cleavage rate or the percentages of embryos at different stages. In addition, we obtained a cashmere goat, which integrated the VEGF gene at the FGF5 site, and the cashmere yield and fibre length of this gene-edited goat were improved. Through next-generation sequencing, we found that the up-regulation of VEGF and the down-regulation of FGF5 affected the cell cycle, proliferation, and vascular tone through the PI3K-AKT signalling pathway and at extracellular matrix-receptor interactions. Owing to this, the gene-edited cashmere goat showed impressive cashmere performance. Overall, in this study, we generated a gene-edited cashmere goat by integrating VEGF at the FGF5 site and provided an animal model for follow-up research on hair growth mechanisms.

In Vitro Hair Dermal Papilla Cells Induction by Fagraea berteroana, a Tree of the Marquesan Cosmetopoeia (French Polynesia)

Fagraea berteroana is a tree used in traditional medicine in various islands of the South Pacific. Here, we studied its hair growth-inducing properties as suggested by one of its Marquesan ethno-uses in haircare. The ethyl acetate extract of the fruits of F. berteroana (FEAE) and four resulting fractions (FEAE-F0, FEAE-F1, FEAE-F2, and FEAE-F3) were tested on hair follicle dermal papilla cells to determine their cell proliferative activity. Furthermore, RT-qPCR analysis enabled gene modulation analysis, while immunostaining of the β-catenin protein was used to follow protein regulation. We found that the plant extracts induced a controlled, dose-dependent cell proliferation. FEAE-F0 simultaneously down-regulated Bone Morphogenetic Protein 2 (BMP2) mRNA expression and upregulated Cyclin-D1 (CCND1) gene expression, which suggests an involvement in the regulation of the Wnt and Transforming Growth Factor beta (TGFβ) pathways that control the hair cycle. FEAE-F0 exhibited a 1.34-fold increase of nuclear β-catenin protein. This is indicative of an active hair growth state. Thus, we conclude that FEAE-F0 could be an innovative candidate in hair care, which opens interesting leads to promote the Marquesan cosmetopoeia.

Hair-Growth-Promoting Effects of Fermented Red Ginseng Marc and Traditional Polyherb Formula in C57BL/6 Mice

An abnormal hair-growth cycle induces hair loss, which affects psychological distress and impairs life quality. Red ginseng marc (RGM) is usually discarded as a byproduct after extracting red ginseng, but several studies have shown that the RGM still has bioactive components including ginsenosides. Therefore, the hair-growth effects of fermented RGM (fRGM) and traditional polyherb formula (PH) were examined in C57BL/6 mice. The dorsal hairs of mice were depilated, and they were topically treated with fRGM or PH at 400, 200 and 100 mg/kg or the combination of both middle doses (combi) once a day for two weeks. The hair-covering regions were significantly increased with higher doses of fRGM and PH and in combi groups, compared with the control treated with distilled water. Hair length, thickness and weight also increased in the treatment groups. In particular, the fRGM and PH increased the anagen-phased hair follicles, the follicular diameters and the dermal thickness. Immunostains for Ki-67 showed the anagen-phased cell division in the treatment groups. The beneficial effects were greater in the high doses of fRGM and PH and the combi groups. These suggest hair-growth-promoting effects of fRGM, PH and the combination by enhancing the hair-growth cycle.

Cepharanthine induces the proliferation of human dermal papilla cells and stimulates vascular endothelial growth factor expression through increased intracellular calcium mobilization and hypoxia-inducible factor activation

BACKGROUND

Cepharanthine (CEP), a compound extracted from the vine Stephania cephalantha, is commonly prescribed to treat alopecia areata; however, the scientific evidence for its efficacy is limited.

AIM

To investigate the effect of CEP and its structural analogues on human hair growth in vitro.

METHODS

The effects of CEP and three of its structural analogues on the proliferation of human dermal papilla cells (hDPCs) and human outer root sheath cells (hORSCs) were investigated. Their effects on vascular endothelial growth factor (VEGF) expression were also assessed by real-time PCR. Activation of pathways leading to VEGF expression, such as intracellular Ca²⁺ mobilization and hypoxia-inducible factor (HIF) expression, was also characterized.

RESULTS

CEP and two of its structural analogues significantly stimulated the growth of hDPCs but not hORSCs. Moreover, CEP and all three structural analogues significantly induced the expression of VEGF in hDPCs. CEP increased the intracellular Ca²⁺ concentration in hDPCs. CEP also increased the expression of HIF-1α and HIF-2α and induced the expression of HIF-responsive genes in hDPCs, even under normoxia.

CONCLUSIONS

These results suggest that CEP and its structural analogues have the potential to restore hair growth by promoting the proliferation of hDPCs and increasing their expression of VEGF.

Interfollicular epidermal stem-like cells for the recreation of the hair follicle epithelial compartment

BACKGROUND

Hair follicle (HF) development and growth are dependent on epithelial-mesenchymal interactions (EMIs). Dermal papilla (DP) cells are recognized as the key inductive mesenchymal player, but the ideal source of receptive keratinocytes for human HF regeneration is yet to be defined. We herein investigated whether human interfollicular epidermal keratinocytes with stem-like features (EpSlKCs), characterized by a α6bri/CD71dim expression, can replace human hair follicular keratinocytes (HHFKCs) for the recreation of the HF epithelium and respective EMIs.

METHODS

The α6bri/CD71dim cellular fraction was selected from the whole interfollicular keratinocyte population through fluorescence-activated cell sorting and directly compared with follicular keratinocytes in terms of their proliferative capacity and phenotype. The crosstalk with DP cells was studied in an indirect co-culture system, and EpSlKC hair forming capacity tested in a hair reconstitution assay when combined with DP cells.

RESULTS

EpSlKCs exhibited a phenotypic profile similar to follicular keratinocytes and were capable of increasing DP cell proliferation and, for short co-culture times, the number of alkaline phosphatase-active cells, suggesting an improvement of their inductivity. Moreover, the recreation of immature HFs and sebaceous glands was observed after EpSlKC and DP cell co-grafting in nude mice.

CONCLUSIONS

Our results suggest that EpSlKCs are akin to follicular keratinocytes and can crosstalk with DP cells, contributing to HF morphogenesis in vivo, thus representing an attractive epithelial cell source for hair regeneration strategies.

Hair growth-promoting activity of components derived from sweet potato shochu

Sweet potato shochu oil is one of the by-products of sweet potato shochu production. We investigated the functionality and industrial use of shochu oil as a food-derived raw material. Because of the increased incidence of self-consciousness in people owing to thinning hair, in this study, we examined the hair growth-inducing effects of shochu oil. Minoxidil, the only topical medication approved for hair growth treatment in Japan, was used as a control for the evaluation of hair growth-promoting activity of shochu oil. Human follicle dermal papilla cells treated with shochu oil showed upregulated expression of vascular endothelial growth factor in a concentration-dependent manner, indicating that shochu oil induced the activation of the hair growth cycle. In vivo, epidermal treatment with shochu oil also promoted hair growth in C3H mice. More than 35 components were detected in shochu oil via gas chromatography-mass spectrometry. The main components, accounting for 98.5% of shochu oil, were as follows, in order of decreasing concentration: ethyl palmitate, ethyl linoleate, ethyl oleate, ethyl stearate, ethyl caprate, ethyl laurate, ethyl myristate, and ethyl α-linolenate. Among these, ethyl palmitate, ethyl linoleate, and ethyl α-linolenate promoted hair growth in C3H mice. These results indicate that shochu oil can be used as a hair restorer. To the best of our knowledge, this study is the first to demonstrate the hair growth-promoting activity of shochu oil.

Amelioration of Androgenetic Alopecia by Algal Oligosaccharides Prepared by Deep-Sea Bacterium Biodegradation

Androgenetic alopecia (AGA) is a dihydrotestosterone (DHT)-mediated hair loss disorder characterized by shortened anagen hair cycle. Oligosaccharides derived from seaweeds possess diverse biological functions. However, little is known about their effects on AGA. In this study, algal oligosaccharide (AOS) was characterized for its mitigation effects on key features involved in AGA pathogenesis, such as DHT- mediated cellular signaling and shortened anagen hair cycle. AOS with varying degrees of polymerization (DP), namely, AOS (DP2), AOS (DP4-6), and AOS (DP8-12), were prepared by agar biodegradation with Flammeovirga pacifica WPAGA1, an agarolytic bacterium isolated from deep-sea sediments. In vitro results showed that AOS with varying DPs significantly ameliorated the DHT-induced alterations of regulatory factors in human hair follicle dermal papilla cells in a dose- and DP-dependent manner, as revealed by the normalization of several hair-growth-stimulating or inhibitory factors. In vivo studies showed that AOS (DP2) extended the anagen phase and thereby delayed catagen progression in mice. Furthermore, AOS (DP2) stimulated dorsal hair growth in mice by increasing hair length, density, and thickness. Therefore, our findings indicated that AOS antagonized key factors involved in AGA pathogenesis, suggesting the potential application of AOS in the prevention and the treatment of AGA.

RNA sequence analysis of dermal papilla cells' regeneration in 3D culture

It is well known that dermal papilla cells (DPCs) are crucial for hair follicle growth and regeneration. However, dermal papilla cells in 2D culture could lose their ability of regeneration after several passage intervals. As opposed to DPCs in 2D culture, the DPCs in 3D culture could passage extensively. However, the molecular mechanisms of DPCs’ regeneration in 3D culture remain unclear. Accordingly, gene sequencing is recommended for the investigation of hair regeneration between 2D and 3D culture, the three groups were established including DPCs in passage 2 in 2D culture, DPCs in passage 8 in 2D culture and DPCs in passage 8 in 3D culture. The differentially expressed genes (DEGs) were identified using the Venn diagram of these three groups, which included 1642 known and 359 novel genes, respectively. A total of 1642 known genes were used for Gene Ontology (GO), Kyoto Gene, Genomic Encyclopedia (KEGG) pathway enrichment and protein‐protein interaction (PPI) analyses, respectively. The functions and pathways of DEGs were enriched in biological regulation, signal transduction and immune system, etc. The key module and the top 10 hub genes (IL1B, CXCL12, HGF, EGFR, APP, CCL2, PTGS2, MMP9, NGF and SPP1) were also identified using the Cytoscape application. Furthermore, the qRT‐PCR results of the three groups validated that the hub genes were crucial for hair growth. In conclusion, the ten identified hub genes and related pathways in the current study can be used to understand the molecular mechanism of hair growth, and those provided a possibility for hair regeneration.

Quercitrin Stimulates Hair Growth with Enhanced Expression of Growth Factors via Activation of MAPK/CREB Signaling Pathway

The present study aimed to investigate the molecular mechanism of quercitrin, a major constituent of Hottuynia cordata extract, for its hair growth stimulating activities in cultured human dermal papilla cells (hDPCs). Quercitrin enhanced the cell viability and cellular energy metabolism in cultured hDPCs by stimulating the production of NAD(P)H and mitochondrial membrane potential (ΔΨ). The expression of Bcl2, an essential marker for anagen hair follicle and cell survival, was increased by quercitrin treatment. Quercitrin also increased the cell proliferation marker Ki67. The expression of growth factors—such as bFGF, KGF, PDGF-AA, and VEGF—were increased by quercitrin both in mRNA and protein levels. In addition, quercitrin was found to increase the phosphorylation of Akt, Erk, and CREB in cultured hDPCs, while inhibitors of MAPKs reversed the effects of quercitrin. Finally, quercitrin stimulated hair shaft growth in cultured human hair follicles. Our data obtained from present study are in line with those previously reported and demonstrate that quercitrin is (one of) the active compound(s) of Hottuynia cordata extract which showed hair growth promoting effects. It is strongly suggested that the hair growth stimulating activity of quercitrin was exerted by enhancing the cellular energy metabolism, increasing the production of growth factors via activation of MAPK/CREB signaling pathway.

Comparative Evaluation of Therapeutic Efficacy of Intralesional Injection of Triamcinolone Acetonide versus Intralesional Autologous Platelet-rich Plasma Injection in Alopecia Areata

Context:

Alopecia areata is a chronic non-scarring alopecia that involves scalp and/or body. Corticosteroids are the most popular drugs for its treatment.

Aim:

The aim of the study was to evaluate the therapeutic efficacy of intralesional injection of triamcinolone acetonide and platelet-rich plasma (PRP) in alopecia areata and to compare the efficacy of these modalities in alopecia areata.

Settings and Design:

This was a randomized controlled comparative study.

Subjects and Methods:

Forty patients were enrolled from the outpatient department and divided into two groups of 20 patients each. Group A and B randomly received intradermal triamcinolone acetonide suspension (10 mg/mL) and PRP, respectively, into the lesion using an insulin syringe in multiple 0.1 mL injections 1cm apart. The injections were repeated every 3 weeks till 12 weeks. The patients were evaluated by Severity of Alopecia Tool (SALT) score and photographically every 3 weeks till the end of 12 weeks and then at the end of 6 months. Statistical analysis used descriptive analysis along with Pearson chi-square test or Fisher exact test, paired samples, and independent samples t test or their nonparametric analogs for continuous variables.

Results:

The reduction in SALT score at each visit with respect to baseline was greater in the triamcinolone group as compared to PRP group. This signifies greater effect of triamcinolone in alopecia areata. Around 50% patients in triamcinolone group and 5% patients in PRP group showed grade V improvement. Pain during intralesional injection was higher in the PRP group.

Conclusion:

Both intralesional triamcinolone and PRP were found to be efficacious in alopecia areata but the latter produced lesser improvement.

HNG, A Humanin Analogue, Promotes Hair Growth by Inhibiting Anagen-to-Catagen Transition

The hair follicle goes through repetitive cycles including anagen, catagen, and telogen. The interaction of dermal papilla cells (DPCs) and keratinocytes regulates the hair cycle and hair growth. Humanin was discovered in the surviving brain cells of patients with Alzheimer’s disease. HNG, a humanin analogue, activates cell growth, proliferation, and cell cycle progression, and it protects cells from apoptosis. This study was performed to investigate the promoting effect and action mechanisms of HNG on hair growth. HNG significantly increased DPC proliferation. HNG significantly increased hair shaft elongation in vibrissa hair follicle organ culture. In vivo experiment showed that HNG prolonged anagen duration and inhibited hair follicle cell apoptosis, indicating that HNG inhibited the transition from the anagen to catagen phase mice. Furthermore, HNG activated extracellular signal-regulated kinase (Erk)1/2, Akt, and signal transducer and activator of transcription (Stat3) within minutes and up-regulated vascular endothelial growth factor (VEGF) levels on DPCs. This means that HNG could induce the anagen phase longer by up-regulating VEGF, which is a Stat3 target gene and one of the anagen maintenance factors. HNG stimulated the anagen phase longer with VEGF up-regulation, and it prevented apoptosis by activating Erk1/2, Akt, and Stat3 signaling.

Transient stimulation of TRPV4-expressing keratinocytes promotes hair follicle regeneration in mice

BACKGROUND AND PURPOSE

Hair follicle telogen to anagen transition results in a break in cellular quiescence of the hair follicle stem cells, which subsequently promotes hair follicle regeneration. Many critical molecules and signalling pathways are involved in hair follicle cycle progression. Transient receptor potential vanilloid 4 (TRPV4) is a polymodal sensory transducer that regulates various cutaneous functions under both normal and disease conditions. However, the role of TRPV4 in hair follicle regeneration in vivo remains incompletely understood.

EXPERIMENTAL APPROACH

Using adult C57BL/6J mice, keratinocyte (K14^Cre ; Trpv4^f/f ) and macrophage (Cx3cr1^Cre ; Trpv4^f/f ) Trpv4 conditional knockout (cKO) mice, Trpv4^-/- mice, we investigated the effect of a single intradermal injection of GSK1016790A, a potent and selective small molecule TRPV4 activator, on hair follicle regeneration. Chemical cues and signal molecules involved in hair follicle cycle progression were measured by immunofluorescence staining, quantitative RT-PCR and western blotting.

KEY RESULTS

Here, we show that a single intradermal injection of GSK1016790A is sufficient to induce telogen to anagen transition and hair follicle regeneration in mice by increasing the expression of the anagen-promoting growth factors and down-regulating the expression of growth factors that inhibit anagen. The action of GSK1016790A relies largely on the function of TRPV4 in skin and involves activation of downstream ERK signalling.

CONCLUSION AND IMPLICATIONS

Our results suggest that transient chemical activation of TRPV4 in the skin induces hair follicle regeneration in mice, which might provide an effective therapeutic strategy for the treatment of hair loss and alopecia.