Aged polystyrene microplastics exacerbate alopecia associated with tight junction injuries and apoptosis via oxidative stress pathway in skin.

Microplastics (MPs) are pervasive pollutants in the natural environment and contribute to increased levels of illness in both animals and humans. However, thespecific impacts of MPs on skin damage and alopeciaare not yet well understood. In this study, we have examined the effects of two types of polystyrene MPs (pristine and aged) on skin and hair follicle damage in mice. UV irradiation changed the chemical and physical properties of the aged MPs, including functional groups, surface roughness, and contact angles. In both in vivo and in vitro experiments, skin and cell injuries related to oxidative stress, apoptosis, tight junctions (TJs), alopecia, mitochondrial dysfunction, and other damages were observed. Mechanistically, MPs and aged MPs can induce TJs damage via the oxidative stress pathway and inhibition of antioxidant-related proteins, and this can lead to alopecia. The regulation of cell apoptosis was also observed, and this is involved in the ROS-mediated mitochondrial signaling pathway. Importantly, aged MPs showed exacerbated toxicity, which may be due to their elevated surface irregularities and altered chemical compositions. Collectively, this study suggests a potential therapeutic approach for alopecia and hair follicle damage caused by MPs pollution.

Vitamin A resolves lineage plasticity to orchestrate stem cell lineage choices.

Lineage plasticity-a state of dual fate expression-is required to release stem cells from their niche constraints and redirect them to tissue compartments where they are most needed. In this work, we found that without resolving lineage plasticity, skin stem cells cannot effectively generate each lineage in vitro nor regrow hair and repair wounded epidermis in vivo. A small-molecule screen unearthed retinoic acid as a critical regulator. Combining high-throughput approaches, cell culture, and in vivo mouse genetics, we dissected its roles in tissue regeneration. We found that retinoic acid is made locally in hair follicle stem cell niches, where its levels determine identity and usage. Our findings have therapeutic implications for hair growth as well as chronic wounds and cancers, where lineage plasticity is unresolved.

Safflower oil body nanoparticles deliver hFGF10 to hair follicles and reduce microinflammation to accelerate hair regeneration in androgenetic alopecia.

Androgenetic alopecia (AGA) affects physical and mental health with limited therapeutic options. Novel materials and delivery methods have considerable potential to improve the current paradigm of treatment. In this study, we used a novel plant nanoparticle of safflower oil body (SOB) loaded with human fibroblast growth factor 10 (hFGF10) to target hair follicles and accelerate hair regeneration in AGA mice with few adverse effects. Our data revealed that the average particle size of SOB-hFGF10 was 226.73 ± 9.98 nm, with a spherical and uniform structure, and that SOB-hFGF10 was quicker to preferentially penetrate into hair follicles than hFGF2 alone. Using a mouse model of AGA, SOB-hFGF10 was found to significantly improve hair regeneration without any significant toxicity. Furthermore, SOB-hFGF10 inhibited dihydrotestosterone (DHT)-induced TNF-α, IL-1ß, and IL-6 overproduction in macrophages in relation to hair follicle microinflammation, thereby enhancing the proliferation of dermal papilla cells. Overall, this study provides an applicable therapeutic method through targeting hair follicles and reducing microinflammation to accelerate hair regeneration in AGA.

Effects of Acanthus ebracteatus Vahl. extract and verbascoside on human dermal papilla and murine macrophage.

Androgenic alopecia is a common type of hair loss, usually caused by testosterone metabolism generating dihydrotestosterone and hair follicular micro-inflammation. These processes induce dermal papilla cells to undergo apoptosis. Currently approved effective medications for alopecia are Finasteride, an oral 5α-reductase inhibitor, Minoxidil, a topical hair growth promoter, and Diclofenac, an anti-inflammatory agent, all of which, however, have several adverse side effects. In our study, we showed the bioactivity of Acanthus ebracteatus Vahl. (AE) extract performed by 95% ethanol, and verbascoside (VB), a biomarker of AE extract. Both AE extract and VB were studied for their effects on dermal papilla cell viability and the cell cycle by using MTT assay and flow cytometry. The effect of an anti-inflammatory activity of AE extract and VB on IL-1ß, NO, and TNF-α, released from LPS induced RAW 264.7 cells, and IL-1α and IL-6 released from irradiated dermal papilla cells were detected using ELISA technique. The preventive effect on dermal papilla cell apoptosis induced by testosterone was determined by MTT assay. In controlled in vitro assays it was found that AE extract and VB at various concentrations induced dermal papilla cell proliferation which was indicated by an increase in the number of cells in the S and G2/M phases of the cell cycle. AE extract at 250 µg/mL concentration or VB at 62.50 µg/mL concentration prevented cell apoptosis induced by testosterone at a statistically significant level. In addition, both AE extract and VB greatly inhibited the release of pro-inflammatory cytokines from RAW 264.7 and dermal papilla cells. The release of IL-1ß, TNF-α, and NO from RAW 264.7 cells, as well as IL-1α and IL-6 from dermal papilla cells, was also diminished by AE extract 250 µg/mL and VB 125 µg/mL. Our results indicate that AE extract and VB are promising ingredients for anti-hair loss applications. However, further clinical study is necessary to evaluate the effectiveness of AE extract and VB as treatment for actual hair loss.

Preparation of topical bimatoprost with enhanced skin infiltration and in vivo hair regrowth efficacy in androgenic alopecia.

To prepare a topical formulation of bimatoprost (BIM) with high skin permeability, we designed a solvent mixture system composed of ethanol, diethylene glycol monoethyl ether, cyclomethicone, and butylated hydroxyanisole, serving as a volatile solvent, nonvolatile co-solvent, spreading agent, and antioxidant, respectively. The ideal topical BIM formulation (BIM-TF#5) exhibited 4.60-fold higher human skin flux and a 529% increase in dermal drug deposition compared to BIM in ethanol. In addition, compared to the other formulations, BIM-TF#5 maximally activated human dermal papilla cell proliferation at a concentration of 5 µM BIM, equivalent to 10 µM minoxidil. Moreover, BIM-TF#5 (0.3% [w/w] BIM) significantly promoted hair regrowth in the androgenic alopecia mouse model and increased the area covered by hair at 10 days by 585% compared to the vehicle-treated mice, indicating that entire telogen area transitioned into the anagen phase. Furthermore, at day 14, the hair weight of mice treated with BIM-TF#5 (5% [w/w] BIM) was 8.45- and 1.30-fold greater than in the 5% (w/w) BIM in ethanol and 5% (w/v) minoxidil treated groups, respectively. In the histological examination, the number and diameter of hair follicles in the deep subcutis were significantly increased in the BIM-TF#5 (0.3 or 5% [w/w] BIM)-treated mice compared to the mice treated with vehicle or 5% (w/w) BIM in ethanol. Thus, our findings suggest that BIM-TF#5 is an effective formulation to treat scalp alopecia, as part of a novel therapeutic approach involving direct prostamide F2α receptor-mediated stimulation of dermal papilla cells within hair follicles.

Physcion, a novel inhibitor of 5α-reductase that promotes hair growth in vitro and in vivo.

Androgenic alopecia (AGA) has a high incidence. Excess dihydrotestosterone in blood capillaries, which is converted from testosterone by 5α-reductase, is an AGA causative factor. We identified the inhibitory activity of four Polygonum multiflorum compounds against 5α-reductase via high-performance liquid chromatography, and the results showed that Physcion was a potent 5α-reductase inhibitor. Additionally, we found that through inhibiting 5α-reductase expression, Physcion could shorten the time of dorsal skin darkening and hair growth, improve hair follicle morphology, and significantly increase hair follicle count. Eventually, through molecular docking study, we found the binding energy and molecular interactions between Physcion and 5α-reductase type II. These results suggested that Physcion is a potent 5α-reductase inhibitor, as well as a new natural medicine for treating AGA.

Inhibition of class I HDACs preserves hair follicle inductivity in postnatal dermal cells.

Induction of new hair follicles (HFs) may be an ultimate treatment goal for alopecia; however, functional cells with HF inductivity must be expanded in bulk for clinical use. In vitro culture conditions are completely different from the in vivo microenvironment. Although fetal and postnatal dermal cells (DCs) have the potential to induce HFs, they rapidly lose this HF inductivity during culture, accompanied by a drastic change in gene expression. This suggests that epigenetic regulation may be involved. Of the various histone deacetylases (HDACs), Class I HDACs are noteworthy because they are ubiquitously expressed and have the strongest deacetylase activity. This study revealed that DCs from postnatal mice rapidly lose HF inductivity and that this reduction is accompanied by a significant decrease in histone H3 acetylation. However, MS-275, an inhibitor of class I HDACs, preserves HF inductivity in DCs during culture, increasing alkaline phosphatase activity and upregulating HF inductive genes such as BMP4, HEY1, and WIF1. In addition, the inhibition of class I HDACs activates the Wnt signaling pathway, the most well-described molecular pathway in HF development, via increased histone H3 acetylation within the promoter region of the Wnt transcription factor LEF1. Our results suggest that class I HDACs could be a potential target for the neogenesis of HFs.

Eruptive Necrotizing Infundibular Crystalline Folliculitis: An Expression of an Abortive Sebaceous Follicular Repair Pathway Linked to Committed Infundibular Stem Cells?

ABSTRACT: Necrotizing infundibular crystalline folliculitis is a rare entity, which is a distinctive clinical and histopathological entity. Eruptive yellow waxy umbilicated folliculocentric plugs clinically correspond to pale crystalline filaments embedded in an amorphous sebum-rich material. Remarkably, only the superficial infundibular ostia remain, and the distended cavity is devoid of a follicular or sebaceous gland remnant. The pathogenesis of this enigmatic event remains to be established. The emergence of necrotizing infundibular crystalline folliculitis (NICF) as a paradoxical side effect of antitumor inhibitors epidermal growth factor receptor vascular endothelial growth factor and more recently programmed death-1 represents the expression of altered molecular pathways that underpin the pathogenesis of NICF. To explore these pathways, it is necessary to explore the hierarchy of follicular stem cells, particularly the potential role of committed infundibular stem cells that play a key role in wound healing. Committed infundibular stem cells are closely linked to the sebaceous gland stem cell axis, and this has relevance in the process of homeostatic repair of sebaceous follicles in the wake of folliculitis. The unscheduled modulation of this infundibular homeostatic sebaceous repair axis by epidermal growth factor receptor vascular endothelial growth factor, and programmed death-1 may lead to an aberrant outcome with metaplasia of infundibular keratinocytes to sebocytes. In the absence of sebaceous gland differentiation, these metaplastic infundibular sebocyte cells would lead to the consumption and loss of the infundibulum as a result of holocrine sebum production. This conceptual pathogenic pathway for NICF is constructed by incorporating recent advances in the fields of follicular stem cells, wound repair, follicular homeostasis, regulatory T cells, and molecular pathways linked to the biologicals inducing NICF.

In Vitro Hair Growth Promoting Effect of a Noncrosslinked Hyaluronic Acid in Human Dermal Papilla Cells.

Dermal papilla cells (DPCs) are a source of nutrients and growth factors, which support the proliferation and growth of keratinocytes as well as promoting the induction of new hair follicles and maintenance of hair growth. The protection from reactive oxygen species (ROS) and the promotion of angiogenesis are considered two of the basal mechanisms to preserve the growth of the hair follicle. In this study, a noncrosslinked hyaluronic acid (HA) filler (HYDRO DELUXE BIO, Matex Lab S.p.A.) containing several amino acids was tested with in vitro assays on human follicle dermal papilla cells (HFDPCs). The experiments were carried out to investigate the possible protection against oxidative stress and the ability to increase the vascular endothelial growth factor (VEGF) release. The results demonstrated the restoration of cell viability against UVB-induced cytotoxicity and an increase in the VEGF secretion. These data demonstrate the capability of the product to modulate human dermal papilla cells, suggesting a future use in mesotherapy, a minimally invasive local intradermal therapy (LIT), after further clinical investigations.

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.

Injectable platelet rich fibrin facilitates hair follicle regeneration by promoting human dermal papilla cell proliferation, migration, and trichogenic inductivity.

Hair follicle regeneration has been successful in mice but failed in human being for years. Dermal papilla cells, a specialized mesenchymal stem cell derived from dermal papilla within hair follicles, is considered the key cells for hair follicle regeneration function as both regeneration initiator and regulator. Injectable platelet rich fibrin (i-PRF), a novel biomaterial rich in a variety of growth factors and three-dimensional scaffolds, has shown promising effects on tissue regeneration. In this study, we aimed to evaluate the application of i-PRF in human hair follicle regeneration by examining the biological effects of i-PRF on human dermal papilla cells (hDPCs). Biomaterial compatibility, cell viability, proliferation, migration, alkaline phosphatase activity and trichogenic inductivity were assessed after exposing hDPCs to different concentrations of i-PRF extracts. In addition, we investigated the ultrastructure of i-PRF with all cell components filtered. The results revealed that i-PRF possessing excellent biocompatibility and could significantly promote hDPCs proliferation, migration, and trichogenic inductivity. Furthermore, the concentration of i-PRF is able to remarkably influence hDPCs behavior in a dose-dependent pattern. Different concentrations exhibited differential effects on hDPCs behavior. In general, lower concentration promotes cell proliferation better than higher concentration, while higher concentration promotes cell function better reversely. Best concentration for hDPCs in vitro expending is 1% concentration. 20% concentration is optimal for hair follicle regeneration. In summary, our findings concluded that i-PRF facilitates hair follicle regeneration by promoting human dermal papilla cell proliferation, migration, and trichogenic inductivity.

Melanogenesis-promoting effect of Cirsium japonicum flower extract in vitro and ex vivo.

OBJECTIVE: In this study, we examined the effect of C. japonicum flower extract (CFE) on melanogenesis and its mechanism in vitro and ex vivo. METHODS: The effect of CFE on melanogenesis was investigated with lightly (HEMn-LP) and moderately (HEMn-MP) pigmented normal human melanocytes, reconstituted three-dimensional skin (3D skin) model and ex vivo human hair follicles. The melanogenesis-inducing effect of CFE was evaluated using melanin content and intracellular tyrosinase activity assay. The amount and type of eumelanin and pheomelanin were analysed by using HPLC method. The mechanism involved in the effect of CFE on hyperpigmentation was explored by cyclic adenosine monophosphate (cAMP) immunoassay and western blot analysis for tyrosinase, microphthalmia-associated transcription factor (MITF) and phosphorylated CRE-binding protein (pCREB) expression. The degree of pigmentation in 3D skin and L-values were measured using a CR-300 chroma meter. The amount of dissolved melanin was measured using a spectrophotometer. The content of melanin in the hair follicles was evaluated by Fontana Masson staining. RESULTS: C. japonicum flower extract significantly increased the melanin content and cellular tyrosinase activity in both HEMn-LP and HEMn-MP cells. The markers of pheomelanin and eumelanin in HEMn-LP and HEMn-MP were also increased by CFE. We observed that CFE treatment on melanocytes increased intracellular cAMP with inducing pCREB and up-regulating the protein levels of TYR and MITF. Furthermore, CFE considerably increased the melanin content in a 3D skin model and ex vivo human hair follicles. CONCLUSIONS: These results suggest that CFE exerts hyperpigmentation activity through cAMP signalling in human melanocytes that it can improve follicular depigmentation and vitiligo by stimulating the melanin synthesis.

OBJECTIF: Dans cette étude, nous avons examiné l'effet de l'extrait de fleur de C. japonicum (EFC) sur la mélanogenèse et son mécanisme in vitro et ex vivo. MÉTHODES: L'effet du EFC sur la mélanogenèse a été étudié avec des mélanocytes humains normaux légèrement (HEMn-LP) et modérément (HEMn-MP) pigmentés, un modèle de peau reconstituée en 3 dimensions (peau 3D) et des follicules pileux ex vivo. L'effet inducteur de la mélanogénèse de la EFC a été évalué en utilisant la teneur en mélanine et le dosage de l'activité de la tyrosinase intracellulaire. La quantité et le type d'eumélanine et de phéomélanine ont été analysés en utilisant la méthode HPLC. Le mécanisme impliqué dans l'effet de la EFC sur l'hyperpigmentation a été exploré par immunoessai à l'adénosine monophosphate cyclique (AMPc) et Western blot pour l'expression de la tyrosinase, du facteur de transcription associé à la microphtalmie (MITF) et l'expression de la protéine CREB phosphorylée. Le degré de pigmentation de la peau 3D, les valeurs L ont été mesurées à l'aide d'un chromamètre CR-300. La quantité de mélanine dissoute a été mesurée à l'aide d'un spectrophotomètre. La teneur en mélanine des follicules pileux a été évaluée par coloration Fontana Masson. RÉSULTATS: EFC a augmenté de manière significative la teneur en mélanine et l'activité de la tyrosinase cellulaire dans les cellules HEMn-LP et HEMn-MP. Les marqueurs de phéomélanine et d'eumélanine dans HEMn-LP et HEMn-MP ont également été augmentés par EFC. Nous avons observé que le traitement EFC sur les mélanocytes augmentait l'AMPc intracellulaire en induisant pCREB et en régulant à la hausse les niveaux de protéines de TYR et MITF. De plus, le EFC a considérablement augmenté la teneur en mélanine dans un modèle de peau 3D et dans les follicules pileux humains ex vivo. CONCLUSIONS: Ces résultats suggèrent que la EFC exerce une activité d'hyperpigmentation via la signalisation de l'AMPc dans les mélanocytes humains qu'elle peut améliorer la dépigmentation folliculaire et le vitiligo en stimulant la synthèse de mélanine.

Amphiregulin promotes hair regeneration of skin-derived precursors via the PI3K and MAPK pathways.

OBJECTIVES: There are significant clinical challenges associated with alopecia treatment, including poor efficiency of related drugs and insufficient hair follicles (HFs) for transplantation. Skin-derived precursors (SKPs) exhibit great potential as stem cell-based therapies for hair regeneration; however, the proliferation and hair-inducing capacity of SKPs gradually decrease during culturing. MATERIALS AND METHODS: We describe a 3D co-culture system accompanied by kyoto encyclopaedia of genes and genomes and gene ontology enrichment analyses to determine the key factors and pathways that enhance SKP stemness and verified using alkaline phosphatase assays, Ki-67 staining, HF reconstitution, Western blot and immunofluorescence staining. The upregulated genes were confirmed utilizing corresponding recombinant protein or small-interfering RNA silencing in vitro, as well as the evaluation of telogen-to-anagen transition and HF reconstitution in vivo. RESULTS: The 3D co-culture system revealed that epidermal stem cells and adipose-derived stem cells enhanced SKP proliferation and HF regeneration capacity by amphiregulin (AREG), with the promoted stemness allowing SKPs to gain an earlier telogen-to-anagen transition and high-efficiency HF reconstitution. By contrast, inhibitors of the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways downstream of AREG signalling resulted in diametrically opposite activities. CONCLUSIONS: By exploiting a 3D co-culture model, we determined that AREG promoted SKP stemness by enhancing both proliferation and hair-inducing capacity through the PI3K and MAPK pathways. These findings suggest AREG therapy as a potentially promising approach for treating alopecia.

Exosomes Derived from Fisetin-Treated Keratinocytes Mediate Hair Growth Promotion.

Enhanced telomerase reverse transcriptase (TERT) levels in dermal keratinocytes can serve as a novel target for hair growth promotion. Previously, we identified fisetin using a system for screening food components that can activate the TERT promoter in HaCaT cells (keratinocytes). In the present study, we aimed to clarify the molecular basis of fisetin-induced hair growth promotion in mice. To this end, the dorsal skin of mice was treated with fisetin, and hair growth was evaluated 12 days after treatment. Histochemical analyses of fisetin-treated skin samples and HaCaT cells were performed to observe the effects of fisetin. The results showed that fisetin activated HaCaT cells by regulating the expression of various genes related to epidermogenesis, cell proliferation, hair follicle regulation, and hair cycle regulation. In addition, fisetin induced the secretion of exosomes from HaCaT cells, which activated ß-catenin and mitochondria in hair follicle stem cells (HFSCs) and induced their proliferation. Moreover, these results revealed the existence of exosomes as the molecular basis of keratinocyte-HFSC interaction and showed that fisetin, along with its effects on keratinocytes, caused exosome secretion, thereby activating HFSCs. This is the first study to show that keratinocyte-derived exosomes can activate HFSCs and consequently induce hair growth.

Glutamic acid promotes hair growth in mice.

Glutamic acid is the main excitatory neurotransmitter acting both in the brain and in peripheral tissues. Abnormal distribution of glutamic acid receptors occurs in skin hyperproliferative conditions such as psoriasis and skin regeneration; however, the biological function of glutamic acid in the skin remains unclear. Using ex vivo, in vivo and in silico approaches, we showed that exogenous glutamic acid promotes hair growth and keratinocyte proliferation. Topical application of glutamic acid decreased the expression of genes related to apoptosis in the skin, whereas glutamic acid increased cell viability and proliferation in human keratinocyte cultures. In addition, we identified the keratinocyte glutamic acid excitotoxic concentration, providing evidence for the existence of a novel skin signalling pathway mediated by a neurotransmitter that controls keratinocyte and hair follicle proliferation. Thus, glutamic acid emerges as a component of the peripheral nervous system that acts to control cell growth in the skin. These results raise the perspective of the pharmacological and nutritional use of glutamic acid to treat skin diseases.

Reversal of alopecia areata, osteoporosis follow treatment with activation of Tgr5 in mice.

BACKGROUND: Alopecia areata is an autoimmune hair loss disease with infiltration of pro-inflammatory cells into hair follicles. The role of Tgr5 in dermatitis has attracted considerable attention. The present study aimed to investigate the effect of Tgr5 in the development of Alopecia areata. METHODS: The study utilized a comparison control group design with four groups of wild-type group, wild-type+INT777 group, Tgr5-/- group, and Tgr5-/-+INT777 group. The mice were treated with INT777 (30 mg/kg/day) or the carrier solution (DMSO) intraperitoneally for 7 weeks, and the back skin was collected and analyzed by histology and immunohistochemistry staining. The lumbar vertebrae 4 has also been analyzed by DXA and Micro-CT. RESULTS: Tgr5-/- mice displayed the decreasingly significant in hair area and length, skin thickness, and the ratio of anagen and telogen, collagen, and mast cell number and loss the bone mass than WT group. After treating with INT777, the appearance of alopecia areata and bone microstructure has improved. Immunohistochemistry and qPCR analysis showed that activation of Tgr5 can down-regulate the express of JAK1, STAT3, IL-6, TNF-α, and VEGF. CONCLUSION: These findings indicate that activation of Tgr5 mediated amelioration of alopecia areata and osteoporosis by down-regulated JAK1-STAT3 signaling pathway.

Argan (Argania Spinosa) press cake extract enhances cell proliferation and prevents oxidative stress and inflammation of human dermal papilla cells.

BACKGROUND: Hair follicle undergoes a growth cycle under the regulation of dermal papilla cells. Due to their enormous roles, these fibroblast cells have been used in various in vitro studies as a screening model to evaluate the effect of hair growth regulating agents. OBJECTIVE: In the current study, we aim to check the hair growth potential effect of Argan press cake (APC) extracted using 50 or 80 % aqueous ethanol on human hair follicle dermal papilla cells (HFDPCs) and to determine the molecular mechanism. METHODS: APC were applied to HFDPCs, then cell proliferation assays, mitochondrial biogenesis assay, and oxidative stress assay were assessed. DNA microarray was performed from the cells treated with our samples and minoxidil. Validation of the results was done using Quantitative Real-Time PCR with primers for hair-growth related genes. GC/MS analysis was used to determine the compounds contained in APC 50 and 80 %. RESULTS: APC enhanced cell proliferation along with the stimulation of the ATP content. Additionally, APC had an anti-oxidant activity against H2O2 mediated oxidative stress preventing dermal papilla cell senescence. Consistent with this, global gene profiling analysis showed an activation of hair growth-related pathway, and a downregulation of inflammation- and oxidative stress-related genes by APC extracts. GC/MS analysis revealed that these extracts contained pure fatty acids, derived sugar chains, and pure compounds including tocopherols, squalene, and spinasterol. CONCLUSION: Taken together, here we showed that APC extracts had an effect on stimulating hair growth while inhibiting the inflammation and the oxidative stress of HFDPCs and thus can potentially contribute to an anti-hair loss drug development.

Dermal papilla cells and melanocytes response to physiological oxygen levels depends on their interactions.

BACKGROUND: Human dermal papilla (DP) cells and melanocytes (hMel) are central players in hair growth and pigmentation, respectively. In hair follicles (HFs), oxygen (O2 ) levels average 5%, being coupled with the production of reactive oxygen species (ROS), necessary to promote hair growth. MATERIALS AND METHODS: DP cell and hMel proliferation and phenotype were studied under physiological (5%O2 , physoxia) or atmospheric (21%O2 , normoxia) oxygen levels. hMel-DP cells interactions were studied in indirect co-culture or by directly co-culturing hMel with DP spheroids, to test whether their interaction affected the response to physoxia. RESULTS: Physoxia decreased DP cell senescence and improved their secretome and phenotype, as well as hMel proliferation, migration, and tyrosinase activity. In indirect co-cultures, physoxia affected DP cells' alkaline phosphatase (ALP) activity but their signalling did not influence hMel proliferation or tyrosinase activity. Additionally, ROS production was higher than in monocultures but a direct correlation between ROS generation and ALP activity in DP cells was not observed. In the 3D aggregates, where hMel are organized around the DP, both hMel tyrosinase and DP cells ALP activities, their main functional indicators, plus ROS production were higher in physoxia than normoxia. CONCLUSIONS: Overall, we showed that the response to physoxia differs according to hMel-DP cells interactions and that the microenvironment recreated when in direct contact favours their functions, which can be relevant for hair regeneration purposes.

Liposomal honokiol promotes hair growth via activating Wnt3a/ß-catenin signaling pathway and down regulating TGF-ß1 in C57BL/6N mice.

Liposomal honokiol isolated from the genus Magnolia has been found to have antiangiogenic, anti-inflammatory and antitumor properties. However, there has no report on its role in hair growth. Hair follicles are life-long cycled organelles that go through from anagen, catagen and telogen stages and are regulated by diverse signaling pathways, including Wnt/ß-catenin, Notch, Epidermal growth factor (EGF) and Sonic hegehog (SHH). Wnt signals are essential for the initiation of hair follicle placode development and a new potential target of hair loss treatment. This study was designed to investigate the effect of liposomal honokiol (Lip-honokiol) on inducing hair anagen. We identified the hair grew out in advance in the shaving area of C57BL/6N mice after the treatment of liposomal honokiol (Lip-honokiol) by daily abdominal injection. We first demonstrated that Lip-Honokiol activated the Wnt3a/ß-catenin pathway and downregulated the transforming growth factor-ß1 (TGF-ß1) to promote hair growth in mice via immunohistochemistry and immunofluorescence staining. These findings suggest that Lip-honokiol activated the Wnt/ß-catenin pathway and accelerated the transfer from the telogen to anagen stage and finally promoted the hair growth.

Ginsenoside Rg4 Enhances the Inductive Effects of Human Dermal Papilla Spheres on Hair Growth Via the AKT/GSK-3ß/ß-Catenin Signaling Pathway.

Ginsenoside Rg4 is a rare ginsenoside that is naturally found in ginseng, and exhibits a wide range of biological activities including antioxidant and anti-inflammatory properties in several cell types. The purpose of this study was to use an in vivo model of hair follicle (HF)-mimic based on a human dermal papilla (DP) spheroid system prepared by three-dimensional (3D) culture and to investigate the effect of Rg4 on the hair-inductive properties of DP cells. Treatment of the DP spheroids with Rg4 (20 to 50 µg/ml) significantly increased the viability and size of the DP spheres in a dose-dependent manner. Rg4 also increased the mRNA and protein expression of DP signature genes that are related to hair growth including ALP, BMP2, and VCAN in the DP spheres. Analysis of the signaling molecules and luciferase reporter assays further revealed that Rg4 induces the activation of phosphoinositide 3-kinase (PI3K)/AKT and the inhibitory phosphorylation of GSK3ß, which activates the WNT/ß-catenin signaling pathway. These results correlated with not only the increased nuclear translocation of ß-catenin following the treatment of the DP spheres with Rg4 but also the significant elevation of mRNA expression of the downstream target genes of the WNT/ß-catenin pathway including WNT5A, ß-catenin, and LEF1. In conclusion, these results demonstrated that ginsenoside Rg4 promotes the hair-inductive properties of DP cells by activating the AKT/GSK3ß/ß-catenin signaling pathway in DP spheres, suggesting that Rg4 could be a potential natural therapy for hair growth.