AP collagen peptides (APCPs) promote hair growth by activating the GSK-3ß/ß-catenin pathway and improve hair condition.

AP collagen peptides (APCPs) are enzymatically decomposed collagen peptides that contain tri-peptides such as glycine-proline-hydroxyproline. We found that APCPs increased the proliferation of both human dermal papilla cells (hDPCs) and human outer root sheath cells (hORSCs). APCPs also stimulated the secretion of several growth factors, including IGFBP-6, PDGF-AB, PIGF and VEGF in hDPCs. Moreover, APCPs enhanced the phosphorylation of Akt(Ser473), GSK-3ß(Ser9) and ß-catenin(Ser675), indicating the activation of the GSK-3ß/ß-catenin signalling pathway. Ex vivo culture of human hair follicles (hHFs) tissue and in vivo patch assay revealed that APCPs promoted the elongation of hHFs and the induction of new hair shafts. In a mouse model, APCPs significantly promoted the transition from telogen to anagen phase and prolonged anagen phase, resulting in increased hair growth. APCPs also improved the thickness, amino acid content (cystine and methionine) and roughness of mouse hair. Taken together, these findings demonstrate that APCPs accelerate hair growth and contribute to overall hair health. Therefore, APCPs have the potential to be utilized as a food supplement and ingredient for preventing hair loss and maintaining hair health.

IGFBP-rP1 is a potential therapeutic target in androgenic alopecia.

The available interventions for androgenic alopecia (AGA), the most common type of hair loss worldwide, remain limited. The insulin growth factor (IGF) system may play an important role in the pathogenesis of AGA. However, the exact role of IGF binding protein-related protein 1 (IGFBP-rP1) in hair growth and AGA has not been reported. In this study, we first found periodic variation in IGFBP-rP1 during the hair cycle transition in murine hair follicles (HFs). We further demonstrated that IGFBP-rP1 levels were lower in the serum and scalp HFs of individuals with AGA than in those of healthy controls. Subsequently, we verified that IGFBP-rP1 had no cytotoxicity to human outer root sheath cells (HORSCs) and that IGFBP-rP1 reversed the inhibitory effects of DHT on the migration of HORSCs in vitro. Finally, a DHT-induced AGA mouse model was created. The results revealed that the expression of IGFBP-rP1 in murine HFs was downregulated after DHT treatment and that subcutaneous injection of IGFBP-rP1 delayed catagen occurrence and prolonged the anagen phase of HFs in mice with DHT-induced AGA. The present work shows that IGFBP-rP1 is involved in hair cycle transition and exhibits great therapeutic potential for AGA.

Ginsenosides in Panax ginseng Extract Promote Anagen Transition by Suppressing BMP4 Expression and Promote Human Hair Growth by Stimulating Follicle-Cell Proliferation.

Studies showing that Panax ginseng promotes hair growth have largely been conducted using mice; there are few reports on how P. ginseng affects human hair growth. In particular, little is known about its effect on the telogen to anagen transition. To determine the effect of P. ginseng on human hair growth and the transition from the telogen to the anagen phase. The effects of P. ginseng extract (PGE) and the three major ginsenoside components, Rb1, Rg1, and Re, on the proliferation of human dermal papilla cells (DPCs) and human outer root sheath cells (ORSCs) were investigated. The effects of these compounds on the cell expression of bone morphogenetic protein 4 (BMP4), fibroblast growth factor 18 (FGF18) and Noggin were assessed by real-time PCR. The effect of PGE on hair-shaft elongation was determined in a human hair follicle organ-culture system. PGE and the three ginsenosides stimulated the proliferation of DPCs and ORSCs and suppressed BMP4 expression in DPCs but did not affect FGF18 expression in ORSCs and Noggin expression in DPCs. PGE stimulated hair-shaft growth. PGE and the ginsenosides Rb1, Rg1, and Re stimulate the transition from the telogen phase to anagen phase of the hair cycle by suppressing BMP4 expression in DPCs. These compounds might be useful for promoting the growth of human hair.

18-ß-Glycyrrhetinic Acid Promotes Hair Growth by Stimulating the Proliferation of Dermal Papilla Cells and Outer Root Sheath Cells, and Extends the Anagen Phase by Inhibiting 5α-Reductase.

18-ß-Glycyrrhetinic acid, a major component of licorice, stimulated the proliferation of both dermal papilla cells and outer root sheath cells isolated from human hair follicles. Thus, suggesting that this compound promotes hair growth. Furthermore, this compound inhibited the activity of testosterone 5α-reductase, an enzyme responsible for converting androgen to dihydroandrogen, with an IC50 of 137.1 µM. 18-ß-Glycyrrhetinic acid also suppressed the expression of transforming growth factor-ß1 (TGF-ß1), which shifts the hair cycle from the anagen phase to the telogen phase. It suggested that this compound may prolong the anagen phase. Based on these findings, this compound could be a potentially effective treatment for androgenetic alopecia.

Dandruff lesional scalp skin exhibits epidermal T cell infiltration and a weakened hair follicle immune privilege.

OBJECTIVE: Dandruff is characterised by the presence of perivascular leukocytes and mild inflammation; however, the immune microenvironment of dandruff-affected scalp skin and the potential changes to the hair follicle's (HF) physiological immune privilege (HF IP) remain unknown. Here, we characterised the HF immune microenvironment and immune privilege status in dandruff-affected scalp skin. METHODS: We assessed relevant key parameters in healthy versus dandruff-affected human scalp biopsies using quantitative immunohistomorphometry, laser capture microdissection, and RNA sequencing. RESULTS: The number of epidermal CD4+ and CD8+ T cells was increased in lesional dandruff scalp skin, while the number of MHC class II+/CD1a+ Langerhans cells was decreased in the infundibulum. The number of intrafollicular and perifollicular CD4+ T cells and CD8+ T cells, perifollicular CD68+ macrophages, and tryptase+ mast cells remained unchanged. Interestingly, MHC class Ia and ß2-microglobulin protein expression were significantly increased specifically in the suprabulbar outer root sheath (ORS) compartment of dandruff-associated HFs. RNAseq analysis of laser capture micro-dissected suprabulbar ORS compartment revealed antigen presentation pathway as the top regulated canonical pathway, along with the upregulation of HF-IP genes such as HLA-C, HLA-DP, and TAP1, which are normally down-regulated in healthy HFs. Intrafollicular protein expression of known HF IP guardians (CD200 and α-MSH) and 'danger signals' (MICA and CXCL10) remained unaltered at the IP sites of dandruff lesional HFs compared to non-lesional and healthy HFs. Instead, the expression of macrophage migration inhibiting factor (MIF), another HF IP guardian, was reduced. CONCLUSION: Together, this work shows that dandruff is associated with epidermal T-cell infiltration and a weakened HF IP in the suprabulbar ORS of HFs in dandruff lesional scalp.

OBJECTIF: Les pellicules sont caractérisées par la présence de leucocytes périvasculaires et une légère inflammation. Cependant, le microenvironnement immunitaire de la peau du cuir chevelu affectée par les pellicules et les modifications potentielles du privilège immunitaire physiologique du follicule pileux (PI FP) restent inconnus. Ici, nous avons caractérisé le microenvironnement immunitaire du follicule pileux (FP) et l'état du privilège immunitaire de la peau du cuir chevelu affectée par les pellicules. MÉTHODES: Nous avons évalué les principaux paramètres pertinents dans des biopsies de cuir chevelu humain sain par rapport à ceux touchés par les pellicules, à l'aide d'une immuno­histomorphométrie quantitative, d'une microdissection au laser et d'un séquençage de l'ARN. RÉSULTATS: Le nombre de lymphocytes T CD4+ et CD8+ épidermiques a augmenté dans la peau du cuir chevelu atteinte de pellicules lésionnelles, tandis que le nombre de cellules de Langerhans du CMH de classe II+/CD1a+ a diminué dans l'infundibulum. Le nombre de lymphocytes T CD4+ et de lymphocytes T CD8+ intrafolliculaires et périfolliculaires, de macrophages CD68+ périfolliculaires et de mastocytes tryptase+ est resté inchangé. Il est intéressant de noter que l'expression des protéines du CMH de classe Ia et de la ß2­microglobuline a augmenté de manière significative dans le compartiment suprabulbaire de la gaine radiculaire externe (GRE) en particulier des FP associés aux pellicules. L'analyse par séquençage ARN du compartiment suprabulbaire de la GRE micro­disséquée au laser a révélé que la voie de présentation de l'antigène était la voie canonique la plus régulée, ainsi que la régulation à la hausse des gènes PI­FP tels que HLA­C, HLA­DP et TAP1, qui sont normalement régulés à la baisse dans les FP sains. L'expression protéique intrafolliculaire des gardiens connus du PI FP (CD200 et α­MSH) et des « signaux de danger ¼ (MICA et CXCL10) est restée inchangée au niveau des sites du PI des FP à pellicules lésionnelles par rapport aux FP sans pellicules lésionnelles et sains. En revanche, l'expression du facteur d'inhibition de la migration des macrophages (MIF), un autre gardien du PI FP, a été réduite. CONCLUSION: L'ensemble de ces travaux montrent que les pellicules sont associées à une infiltration épidermique des lymphocytes T et à un affaiblissement du PI FP dans la GRE suprabulbaire des FP du cuir chevelu atteint de pellicules lésionnelles.

Kartogenin regulates hair growth and hair cycling transition.

Background: Kartogenin is a heterocyclic compound able to promote the proliferation, migration, and differentiation of various cell types and induce cartilage-like tissue regeneration. However, the role of kartogenin in hair follicles (HFs), remains unknown. We therefore investigated the effects of kartogenin on the regulation of hair growth and hair growth cycle transition. Methods: The effects of kartogenin on the proliferation, cell cycle status, and migration of primary human outer root sheath cells (ORSCs) were evaluated by MTS assay, flow cytometry, Transwell® and scratch assays, respectively. We exposed ORSCs to kartogenin (1 µM) and determined changes in mRNA and protein levels of transforming growth factor (TGF)-ß2/Smad signaling molecules by reverse transcription polymerase chain reaction, western blotting, and immunofluorescence. We also examined the effects of kartogenin (10 µM) on HFs in mice by histology following cutaneous injection. Results: Kartogenin enhanced ORSC proliferation and migration function in a dose-dependent manner, and downregulated the expression of TGF-ß2/Smad signaling molecules in vitro. Injection of kartogenin delayed catagen phase and increased regenerated hair length in mice in vivo. Conclusions: Kartogenin modulates HF growth and regulates the hair cycle and the TGF-ß2/Smad signaling pathway, providing a potential new approach for the treatment of hair loss.

Hair Growth Regulation by Fibroblast Growth Factor 12 (FGF12).

The fibroblast growth factor (FGF) family has various biological functions, including cell growth, tissue regeneration, embryonic development, metabolism, and angiogenesis. In the case of hair growth, several members of the FGF family, such as FGF1 and FGF2, are involved in hair growth, while FGF5 has the opposite effect. In this study, the regulation of the hair growth cycle by FGF12 was investigated. To observe its effect, the expression of FGF12 was downregulated in mice and outer root sheath (ORS) by siRNA transfection, while FGF12 overexpression was carried out using FGF12 adenovirus. For the results, FGF12 was primarily expressed in ORS cells with a high expression during the anagen phase of hair follicles. Knockdown of FGF12 delayed telogen-to-anagen transition in mice and decreased the hair length in vibrissae hair follicles. It also inhibited the proliferation and migration of ORS cells. On the contrary, FGF12 overexpression increased the migration of ORS cells. FGF12-overexpressed ORS cells induced the telogen-to-anagen transition in the animal model. In addition, FGF12 overexpression regulated the expression of PDGF-CC, MDK, and HB-EGF, and treatment of these factors exhibited hair growth promotion. Altogether, FGF12 promoted hair growth by inducing the anagen phase of hair follicles, suggesting the potential for hair loss therapy.

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; ß-catenin; versican), which trigger or elongate the anagen phase, were stimulated by D-panthenol. On the other hand, D-panthenol reduced TGF-ß1 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.

Osteogenic Potential of Mesenchymal Stem Cells from Adipose Tissue, Bone Marrow and Hair Follicle Outer Root Sheath in a 3D Crosslinked Gelatin-Based Hydrogel.

Bone transplantation is regarded as the preferred therapy to treat a variety of bone defects. Autologous bone tissue is often lacking at the source, and the mesenchymal stem cells (MSCs) responsible for bone repair mechanisms are extracted by invasive procedures. This study explores the potential of autologous mesenchymal stem cells derived from the hair follicle outer root sheath (MSCORS). We demonstrated that MSCORS have a remarkable capacity to differentiate in vitro towards the osteogenic lineage. Indeed, when combined with a novel gelatin-based hydrogel called Osteogel, they provided additional osteoinductive cues in vitro that may pave the way for future application in bone regeneration. MSCORS were also compared to MSCs from adipose tissue (ADMSC) and bone marrow (BMMSC) in a 3D Osteogel model. We analyzed gel plasticity, cell phenotype, cell viability, and differentiation capacity towards the osteogenic lineage by measuring alkaline phosphatase (ALP) activity, calcium deposition, and specific gene expression. The novel injectable hydrogel filled an irregularly shaped lesion in a porcine wound model displaying high plasticity. MSCORS in Osteogel showed a higher osteo-commitment in terms of calcium deposition and expression dynamics of OCN, BMP2, and PPARG when compared to ADMSC and BMMSC, whilst displaying comparable cell viability and ALP activity. In conclusion, autologous MSCORS combined with our novel gelatin-based hydrogel displayed a high capacity for differentiation towards the osteogenic lineage and are acquired by non-invasive procedures, therefore qualifying as a suitable and expandable novel approach in the field of bone regeneration therapy.

Mesenchymal Stem Cells Antagonize IFN-Induced Proinflammatory Changes and Growth Inhibition Effects via Wnt/ß-Catenin and JAK/STAT Pathway in Human Outer Root Sheath Cells and Hair Follicles.

Mesenchymal stem cell therapy (MSCT) has been shown to be a new therapeutic option for treating alopecia areata (AA). Outer root sheath cells (ORSCs) play key roles in maintaining the hair follicle structure and supporting the bulge area. In human ORSCs (hORSCs), the mechanism for this process has not been extensively studied. In this study, we aimed to examine the influence of human hematopoietic mesenchymal stem cells (hHMSCs) in the hORSCs in vitro model of AA and determine the mechanisms controlling efficacy. Interferon-gamma (IFN-γ) pretreatment was used to induce an in vitro model of AA in hORSCs. The effect of MSCT on the viability and migration of hORSCs was examined using co-cultures, the MTT assay, and migration assays. We investigated the expression of molecules related to the Wnt/ß-catenin pathway, JAK/STAT pathway, and growth factors in hHMSC-treated hORSCs by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses. hHMSCs increased hORSC viability and migration when they were co-cultured. hHMSCs reverted IFN-γ-induced expression-including NLRP3, ASC, caspase-1, CXCL-9 through 11, IL-1ß, and IL-15-and upregulated several growth factors and hair stem cell markers. hHMSCs activated several molecules in the Wnt/ß-catenin signaling pathway, such as in the Wnt families, ß-catenin, phosphorylated GSK-3ß and cyclin D1, and suppressed the expression of DKK1 induced by IFN-γ in hORSCs. hHMSCs suppressed the phosphorylation of JAK1 to 3, STAT1, and STAT3 compared to the controls and IFN-γ-pretreated hORSCs. These results demonstrate that hHMSCs increased hORSC viability and migration in the in vitro AA model. Additionally, MSCT definitely stimulated anagen survival and hair growth in an HF organ culture model. MSCT appeared to be associated with the Wnt/ß-catenin and JAK/STAT pathways in hORSCs.

Inhibition of Rab27a and Rab27b Has Opposite Effects on the Regulation of Hair Cycle and Hair Growth.

Rab27a/b are known to play an important role in the transport of melanosomes, with their knockout causing silvery gray hair. However, the relationship between Rab27a/b and hair growth is not well known. To evaluate the role of Rab27a/b in hair cycle, we investigated the expression of Rab27a/b during hair cycling and human outer root sheath (hORS) cells. The expression of Rab27a in ORS cells was mainly detected at the anagen, whereas expression of Rab27b in ORS, and epidermal cells was strongly expressed at the telogen. Additionally, Rab27a/b were expressed in the Golgi of hORS cells. To evaluate the role of Rab27a/b in hair growth, telogen-to-anagen transition animal and vibrissae hair follicles (HFs) organ culture models were assayed using Rab27a/b siRNAs. The knockdown of Rab27a or Rab27b suppressed or promoted hair growth, respectively. These results were also confirmed in human dermal papilla cells (hDPCs) and hORS cells, showing the opposite mitogenic effects. Moreover, Rab27b knockdown increased the expression levels of various growth factors in the hDPCs and hORS cells. Overall, the opposite temporal expression patterns during hair cycling and roles for hair growth of Rab27a/b suggested that Rab27a/b might regulate the hair cycle. Therefore, our study may provide a novel solution for the development of hair loss treatment by regulating Rab27a/b levels.

Ectodysplasin-A2 induces apoptosis in cultured human hair follicle cells and promotes regression of hair follicles in mice.

Ectodysplasin is a ligand of the TNF family that plays a key role in ectodermal differentiation. EDA-A1 and EDA-A2 are two isoforms of ectodysplasin that differ only by the insertion of two amino acids and bind to two different receptors, ectodysplasin A receptor (EDAR) and ectodysplasin A2 receptor (EDA2R), respectively. Mutations of EDA-A1 and its receptor EDAR have been associated with hypohidrotic ecodermal dysplasia (HED). However, the role of EDA-A2 and the expression pattern of EDA2R in human hair follicles and in the mouse hair growth cycle have not been reported. In this study, we first investigated the expression of EDA2R in human hair follicles and in cultured follicular cells. EDA2R was strongly expressed in outer root sheath (ORS) cells and weakly expressed in dermal papilla (DP) cells. EDA-A2 induced the apoptosis of both ORS cells and DP cells via the activation of cleaved caspase-3. In addition, EDA2R was highly expressed in the late anagen phase compared with other phases in the hair growth cycle. Moreover, EDA-A2 induced apoptosis in cultured human hair follicle cells and in the mouse hair growth cycle, causing the premature onset of the catagen phase. Collectively, our results suggest that EDA-A2/EDA2R signaling could inhibit hair growth, and an inhibitor of EDA-A2/EDA2R signaling may be a promising agent for the treatment and prevention of hair loss.

Restoration of hair-inductive activity of cultured human follicular keratinocytes by co-culturing with dermal papilla cells.

Hair follicle outer root sheath (ORS) cells can be expanded in vitro, but often lose receptivity to hair-inducing dermal signals. Recent studies have shown hair-inductive activity (trichogenicity) can be restored in rat ORS cells expanded with a fibroblast feeder by co-culturing with rat vibrissae dermal papilla (DP) cells. In this study, we investigated whether the trichogenicity of human ORS cells can be restored by co-culturing with human DP cells. ORS cells from human scalp hair follicles were cultured independently or with DP cells for 5 days and implanted into nude mice alongside freshly isolated neonatal mouse dermal cells. Although there was no hair induction when monocultured ORS cells were implanted, it was observed in co-cultured ORS cells. We also observed differential regulation of a number of genes in ORS cells co-cultured with DP cells compared to monocultured ORS cells as examined by microarray. Taken together, our data strongly suggest that human DP cells restore the trichogenicity of co-cultured ORS cells by influencing ORS gene expression through paracrine factors.

Regulation of hair follicle development by exosomes derived from dermal papilla cells.

BACKGROUND: Dermal papilla cells (DPCs) play a critical role in the regulation of hair follicle (HF) growth, formation, and cycling. DPCs are thought to regulate HF growth through a paracrine mechanism, in which exosomes may play a critical role. METHODS: DPC-Exos were cutaneously injected into HFs at different HF cycle stages and the effects were evaluated by histological and immunohistochemical analyses. The effects of DPC-Exos on proliferation, migration, and cell cycle status of outer root sheath cells (ORSCs) were evaluated. After treatment of DPC-Exos, changes in mRNA and protein levels of ß-catenin and Sonic hedgehog (Shh) in ORSCs were detected. RESULTS: DPC-Exos were approximately 105 nm in diameter and expressed tumor susceptibility gene 101, cluster of differentiation (CD)9, and CD63. Injection of DPC-Exos accelerated the onset of HF anagen and delayed catagen in mice. Immunohistochemical analyses revealed that ß-catenin and Shh levels were upregulated in the skin. In vitro, DPC-Exo treatment enhanced ORSC proliferation and migration, and stimulated the expression of ß-catenin and Shh. CONCLUSION: DPC-Exos contribute to the regulation of HF growth and development, and provide a potential avenue for the treatment of hair loss.

Decorin promotes proliferation and migration of ORS keratinocytes and maintains hair anagen in mice.

DECORIN is a prototypical member of the small leucine-rich proteoglycan (SLRP) family that plays important roles in numerous biological processes and cellular biological pathways. We previously showed that Decorin expression was highly enhanced in mouse dorsal hair follicles (HFs) during the anagen phase and was reduced during the catagen and telogen phases, suggesting that Decorin might modulate follicular cycling and morphogenesis. In this study, to further clarify the effects of DECORIN on hair cells and the cycling transition, an in vitro overexpression strategy and Decorin-null (Dcn-/- ) mice were used to investigate the effects of DECORIN on outer root sheath (ORS) keratinocytes. DECORIN overexpression significantly enhanced proliferation and migration in ORS keratinocytes in vitro. Moreover, DECORIN overexpression upregulated the mRNA and protein expression levels of WNT10b, ß-CATENIN and LEF1. The DECORIN overexpression-induced increase in the proliferation and migration of ORS keratinocytes was partially inhibited by a Wnt/ß-catenin inhibitor. Furthermore, Dcn-/- mice had a shortened anagen phase and lower levels of ß-catenin expression than were observed in wild-type mice in imaging and histological analyses. Taken together, these findings suggest that DECORIN promotes the proliferation and migration of ORS keratinocytes in vitro and maintains hair anagen in mice.

A human serum-enriched medium formulation supports high viability and marker expression in primary melanocyte cultures from the outer root sheath and epidermis.

Formulating clinically relevant melanocyte cultivation media that maintain the balance between proliferation and maturation to functional melanocytes is a major experimental and regulatory challenge. Within the translation of human melanocytes from the outer root sheath of human hair follicle (HUMORS), we developed a melanocyte medium free of chemical mitogens, chemical melanogenesis enhancers and bovine products, enabling proliferation as well as melanotic differentiation. The formulation involved the replacement of bovine pituitary extract (BPE) and bovine serum (FBS) with human serum (HS) combined with ascorbic acid, CaCl2 , epinephrine, L-glutamine, insulin and fibroblast growth factor. The cultivation efficiency was characterized through proliferation and exertion of melanotic phenotype, gene and protein expression of melanotic markers and melanin content. Having established an application-directed BPE-free formulation, we then re-formulated a research-grade medium with BPE for purposes of even more effective in vitro cultivation, adjusted to specific requirements of HUMORS and normal human epidermal melanocytes (NHEM).

Establishment of dermal sheath cell line from Cashmere goat and characterizing cytokeratin 13 as its novel biomarker.

OBJECTIVE: To establish a dermal sheath cell line, a dermal papilla cell line and a outer root sheath cell line from Cashmere goat and clarify the similarities and differences among them. RESULTS: We established a dermal sheath cell line, a dermal papilla cell line and a outer root sheath cell line from the pelage skin hair follicles of Cashmere goat. The growth rate of dermal sheath cells was intermediate between that of dermal papilla cells and outer root sheath cells. Immunofluorescence experiments and reverse transcription-polymerase chain reaction analysis showed that at both the transcriptional and translational levels, the dermal sheath cells were alpha-smooth muscle actin (α-SMA)+/cytokeratin 13+, while the dermal papilla cells were α-SMA+/cytokeratin 13- and the outer root sheath cells were α-SMA-/cytokeratin 13+. Patterns of cytokeratin 13 expression could distinguish the dermal sheath cells from the dermal papilla cells. CONCLUSIONS: These results suggest that cytokeratin 13 could serve as a novel biomarker for dermal sheath cells of Cashmere goat, and should prove useful for researchers investigating dermal stem cells or interaction of different types of cells during hair cycle.

Giant proliferating trichilemmal cyst arising from a nevus sebaceus growing for 30 years.

Nevus sebaceus of Jadassohn, a congenital cutaneous hamartoma, has the potential to develop into various epidermal adnexal-origin neoplasms. While the most common neoplasms are trichoblastoma or syringocystadenoma, proliferating trichilemmal cysts are exceptionally rare. We report a case of a 63-year-old Cuban male with a giant proliferating trichilemmal cyst arising from a nevus sebaceus on the right shoulder which had been growing for 30 years. Proliferating trichilemmal cysts arising from nevus sebaceus cases are difficult to diagnose clinically and histologically as they are very rare and have not been defined by exact diagnostic criteria. Our case creates awareness of this particular tumor in nevus sebaceus and shares clinical and histological diagnostic information that can be used to make a proper diagnosis.

A new path in defining light parameters for hair growth: Discovery and modulation of photoreceptors in human hair follicle.

BACKGROUND AND OBJECTIVE: Though devices for hair growth based on low levels of light have shown encouraging results, further improvements of their efficacy is impeded by a lack of knowledge on the exact molecular targets that mediate physiological response in skin and hair follicle. The aim of this study was to investigate the expression of selected light-sensitive receptors in the human hair follicle and to study the impact of UV-free blue light on hair growth ex vivo. MATERIAL AND METHODS: The expression of Opsin receptors in human skin and hair follicles has been characterized using RT-qPCR and immunofluorescence approaches. The functional significance of Opsin 3 was assessed by silencing its expression in the hair follicle cells followed by a transcriptomic profiling. Proprietary LED-based devices emitting two discrete visible wavelengths were used to access the effects of selected optical parameters on hair growth ex vivo and outer root sheath cells in vitro. RESULTS: The expression of OPN2 (Rhodopsin) and OPN3 (Panopsin, Encephalopsin) was detected in the distinct compartments of skin and anagen hair follicle. Treatment with 3.2 J/cm2 of blue light with 453 nm central wavelength significantly prolonged anagen phase in hair follicles ex vivo that was correlated with sustained proliferation in the light-treated samples. In contrast, hair follicle treatment with 3.2 J/cm2 of 689 nm light (red light) did not significantly affect hair growth ex vivo. Silencing of OPN3 in the hair follicle outer root sheath cells resulted in the altered expression of genes involved in the control of proliferation and apoptosis, and abrogated stimulatory effects of blue light (3.2 J/cm2 ; 453 nm) on proliferation in the outer root sheath cells. CONCLUSIONS: We provide the first evidence that (i) OPN2 and OPN3 are expressed in human hair follicle, and (ii) A 453 nm blue light at low radiant exposure exerts a positive effect on hair growth ex vivo, potentially via interaction with OPN3. Lasers Surg. Med. 49:705-718, 2017. © 2017 Wiley Periodicals, Inc.

Wnt/ß-catenin and ERK pathway activation: A possible mechanism of photobiomodulation therapy with light-emitting diodes that regulate the proliferation of human outer root sheath cells.

BACKGROUND: Outer root sheath cells (ORSCs) play important roles in maintaining hair follicle structure and provide support for the bulge area. The hair growth promoting effects of photobiomodulation therapy (PBMT) have been reported, but the mechanisms for this in human ORCs (hORSCs) have rarely been studied. OBJECTIVE: The aim of this study was to investigate the effect of various wavelengths of light-emitting diode (LED) irradiation on human ORSCs (hORSCs). METHODS: LED irradiation effects on hORSC proliferation and migration were examined with MTT assay, BrdU incorporation assay and migration assays. hORSCs were irradiated using four LED wavelengths (415, 525, 660, and 830 nm) with different low energy levels. LED irradiation effects on the expression of molecules associated with the Wnt/ß-catenin signaling and ERK pathway, hair stem cell markers, and various growth factors and cytokines in hORSCs were examined with real-time PCR and Western blot assay. The effect of the LED-irradiated hORSCs on cell proliferation of human dermal papilla cells (hDPCs) was examined with co-culture and MTT assay. RESULTS: PBMT with LED light variably promoted hORSC proliferation and suppressed cell apoptosis depending on energy level. LED irradiation induced Wnt5a, Axin2, and Lef1 mRNA expression and ß-catenin protein expression in hORSCs. Phosphorylation of ERK, c-Jun, and p38 in hORSCs was observed after LED light irradiation, and ERK inhibitor treatment before irradiation reduced ERK and c-Jun phosphorylation. Red light-treated hORSCs showed substantial increase in IL-6, IL-8, TNF-a, IGF-1, TGF-ß1, and VEGF mRNA. Light irradiation at 660 and 830 nm projected onto hORSCs accelerated in vitro migration. LED-irradiated hORSCs increased hDPCs proliferation when they were co-cultured. The conditioned medium from LED-irradiated hORSCs was sufficient to stimulate hDPCs proliferation. CONCLUSION: These results demonstrate that LED light irradiation induced hORSC proliferation and migration and inhibited apoptosis in vitro. The growth-promoting effects of LEDs on hORSCs appear to be associated with direct stimulation of the Wnt5a/ß-catenin and ERK signaling pathway. Lasers Surg. Med. 49:940-947, 2017. © 2017 Wiley Periodicals, Inc.