ICP5249 Promotes Hair Growth by Activating the AMPK-Autophagy Signaling Pathway.

Autophagy is essential for regulating hair growth. Accordingly, we developed autophagy activator ICP5249 (pentasodium tetracarboxymethyl palmitoyl dipeptide) and investigated its potential role in hair growth. We evaluated its effect on hair growth using in vitro human dermal papilla cells (hDPCs) culture model, human hair follicles (hHFs) organ culture model, and telogenic mouse model. ICP5249 increased hDPCs proliferation and alkaline phosphatase (ALP) expression. It also increased microtubule-associated protein (MAP) light chain 3- II (LC3-II) expression and AMP-activated protein kinase α (AMPKα) and unc-51-like kinase 1 (ULK1) phosphorylation in hDPCs. ICP5249 extended the length of hHFs and increased LC3 II expression. Consistently, ICP5249 also significantly increased hair growth area, dermis thickness, and anagen and telogen ratio in telogenic mice. Furthermore, it upregulated Ki-67 and LC3-II expression and AMPKα phosphorylation on the mice's dorsal skin. To investigate whether AMPK regulates ICP5249-induced hair growth, following treatment with the compound C, AMPK inhibitor, the activity of ICP5249 was evaluated. The effects of ICP5249 on hair growth were assessed following pretreatment with the AMPK inhibitor compound C. The results showed that compound C suppressed ICP5249-mediated proliferation and hair inductivity in hDPCs. Additionally, compound C inhibited ICP5249-mediated hair growth area, dermis thickness, anagen and telogen ration, and LC3-II expression in mice, suggesting that ICP5249 promotes hair growth by modulating autophagy, with AMPKα playing a regulatory role in this process. Taken together, we demonstrate that ICP5249 has the potential as an ingredient for improving hair growth.

Effects of Nannochloropsis salina Fermented Oil on Proliferation of Human Dermal Papilla Cells and Hair Growth.

The hair follicle is the basis of hair regeneration, and the dermal papilla is one of the most important structures in hair regeneration. New intervention and reversal strategies for hair loss may arise due to the prevention of oxidative stress. GC/MS analysis was used to determine the compounds contained in NSO. Then, NSO was applied to DPC for cell proliferation and oxidative stress experiments. RNA-seq was performed in cells treated with NSO and minoxidil. The quantitative real-time polymerase chain reaction (qRT-PCR) was applied to verify the gene expression. The effects of NSO on hair length, weight, the number and depth of hair follicles, and the dermal thickness were also studied. GC/MS analysis showed that the main components of NSO were eicosapentaenoic acid, palmitic acid, and linoleic acid. NSO promotes DPC proliferation and reduces H2O2-mediated oxidative damage. NSO can also activate hair growth-related pathways and upregulate antioxidant-related genes analyzed by gene profiling. The topical application of NSO significantly promotes hair growth and increases hair length and weight in mice. NSO extract promotes hair growth and effectively inhibits oxidative stress, which is beneficial for the prevention and treatment of hair loss.

Irisin promotes hair growth and hair cycle transition by activating the GSK-3ß/ß-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/ß-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/ß-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/ß-catenin pathway and highlight its therapeutic potential in hair loss treatment.

Exosomal miR-222-3p derived from dermal papilla cells inhibits melanogenesis in melanocytes by targeting SOX10 in rabbits.

Objective: Dermal papilla cells (DPCs) play a pivotal role in hair follicle development and can modulate melanogenesis in melanocytes (MCs) through their microenvironment. Our previous studies have demonstrated that the level of exosomal miR-222-3p derived from DPCs of white Rex rabbits are significantly higher than those of black Rex rabbits. However, the specific role and underlying molecular mechanisms of exosomal miR-222-3p in melanogenesis remain elusive. Methods: DPCs and MCs were isolated from hair follicles of Rex rabbits and identified using western blotting (WB) and immunofluorescent staining. Exosomes derived from DPCs (DPCs-exos) were characterized using nanoparticle tracking analysis, transmission electron microscopy, and WB. To investigate cell-cell crosstalk mediated by exosomes, MCs were co-cultured with CM-Dil-labeled DPCs-exos. The expression of miR-222-3p in skin tissue and exosomes was quantitatively assessed using quantitative real-time PCR (qRT-PCR). The transmission of DPCs-secreted exosomal miR-222-3p to MCs was demonstrated using Cy3-labeled miR-222-3p in conjunction with transwell assays. The impact of miR-222-3p on melanin synthesis was evaluated using the NaOH method, CCK-8, and Annexin V-FITC/PI assays. SOX10, a potential target gene regulated by miR-222-3p, was validated using a dual-luciferase reporter assay, site-specific mutation, and WB. Results: Increased levels of miR-222-3p were observed in the skin and DPCs-exos of white Rex rabbits compared to those of black Rex rabbits. Effective internalization of CM-Dil-labeled DPCs-exos by MCs was observed. Furthermore, exosomal miR-222-3p derived from DPCs was transferred to MCs. Functionally, miR-222-3p significantly inhibited MCs proliferation, induced apoptosis and inhibited melanin synthesis. SOX10 was confirmed as a direct target of miR-222-3p in this regulatory cascade. Conclusion: The findings demonstrate that exosomal miR-222-3p, derived from DPCs, suppresses melanogenesis in MCs by targeting SOX10, thus unveiling a novel mechanism of exosome involvement in melanogenesis.

Hair Growth Promoting Effects of 15-Hydroxyprostaglandin Dehydrogenase Inhibitor in Human Follicle Dermal Papilla Cells.

Prostaglandin E2 (PGE2) is known to be effective in regenerating tissues, and bimatoprost, an analog of PGF2α, has been approved by the FDA as an eyelash growth promoter and has been proven effective in human hair follicles. Thus, to enhance PGE2 levels while improving hair loss, we found dihydroisoquinolinone piperidinylcarboxy pyrazolopyridine (DPP), an inhibitor of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), using DeepZema®, an AI-based drug development program. Here, we investigated whether DPP improved hair loss in human follicle dermal papilla cells (HFDPCs) damaged by dihydrotestosterone (DHT), which causes hair loss. We found that DPP enhanced wound healing and the expression level of alkaline phosphatase in DHT-damaged HFDPCs. We observed that DPP significantly down-regulated the generation of reactive oxygen species caused by DHT. DPP recovered the mitochondrial membrane potential in DHT-damaged HFDPCs. We demonstrated that DPP significantly increased the phosphorylation levels of the AKT/ERK and activated Wnt signaling pathways in DHT-damaged HFDPCs. We also revealed that DPP significantly enhanced the size of the three-dimensional spheroid in DHT-damaged HFDPCs and increased hair growth in ex vivo human hair follicle organ culture. These data suggest that DPP exhibits beneficial effects on DHT-damaged HFDPCs and can be utilized as a promising agent for improving hair loss.

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.

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.

The Role of BMP7 in the Proliferation of Hu Sheep Dermal Papilla Cells Is Influenced by DNA Methylation.

Previous studies have shown that the BMP7 gene is differentially expressed in Hu sheep lamb skin of different pattern types, and its expression level is significantly correlated with hair follicle indices of different pattern types, but the molecular mechanism of the differential expression of the BMP7 gene remains unclear. This study investigated the effect of DNA methylation on the transcriptional expression of BMP7. Firstly, we found that the mRNA expression of the BMP7 gene and the activity of the core promoter of the BMP7 gene were upregulated after 5-Aza-Deoxycytidine-induced demethylation treatment using qRT-PCR and double luciferase reporter assay. Then, we found that the proliferation of Hu sheep DPCs in vitro was promoted after 5-Aza-Deoxycytidine-induced demethylation treatment through qRT-PCR, CCK-8, and EdU assay, and that the overexpression of DNMT1 in DPCs induced the opposite effect. In addition, the results of the cell cycle assay reveal that the percentage of cells in the S phase was increased after 5-Aza-Deoxycytidine-induced demethylation treatment, and that the percentage of cells in the S phase was decreased after overexpression of DNMT1 in DPCs. This study indicated that the differential expression of the BMP7 gene in different patterns of Hu sheep lamb skin may be regulated by DNA methylation modification. In addition, DNA methylation can regulate the proliferation and cell cycle of DPCs in Hu sheep.

Combination of Autophagy and Stem Cell Enhancing Properties of Natural Product Extracts in Human Dermal Papilla Stem Cells.

BACKGROUND/AIM: Dermal papilla (DP) stem cells are known for their remarkable regenerative capacity, making them a valuable model for assessing the effects of natural products on cellular processes, including stemness, and autophagy. MATERIALS AND METHODS: Autophagy and stemness characteristics were assessed using real-time RT-PCR to analyze mRNA levels, along with immunofluorescence and western blot techniques for protein level evaluation. RESULTS: Butterfly Pea, Emblica Fruits, Kaffir Lime, and Thunbergia Laurifolia extracts induced autophagy in DP cells. Kaffir Lime-treated cells exhibited increase in the OCT4, NANOG, and SOX2 mRNA (6-, 5, and 5.5-fold, respectively), and protein levels (4-, 3-, and 1.5-fold, respectively). All extracts activated the survival protein kinase B (Akt) in DP cells. CONCLUSION: Natural products are a promising source for promoting hair growth by rejuvenating hair stem cells.

Autophagy Dysfunction: The Kernel of Hair Loss?

Autophagy is recognized as a crucial regulatory process, instrumental in the removal of senescent, dysfunctional, and damaged cells. Within the autophagic process, lysosomal digestion plays a critical role in the elimination of impaired organelles, thus preserving fundamental cellular metabolic functions and various biological processes. Mitophagy, a targeted autophagic process that specifically focuses on mitochondria, is essential for sustaining cellular health and energy balance. Therefore, a deep comprehension of the operational mechanisms and implications of autophagy and mitophagy is vital for disease prevention and treatment. In this context, we examine the role of autophagy and mitophagy during hair follicle cycles, closely scrutinizing their potential association with hair loss. We also conduct a thorough review of the regulatory mechanisms behind autophagy and mitophagy, highlighting their interaction with hair follicle stem cells and dermal papilla cells. In conclusion, we investigate the potential of manipulating autophagy and mitophagy pathways to develop innovative therapeutic strategies for hair loss.

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)-ß 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.

Ellagic acid inhibits dihydrotestosterone-induced ferroptosis and promotes hair regeneration by activating the wnt/ß-catenin signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Androgenic alopecia (AGA) is the most prevalent form of hair loss in clinical practice and affects the physical and psychological well-being of adolescents. Paeonia lactiflora Pallas (PL), which is widely used in traditional Chinese medicine, enhances blood function and promotes hair growth, and ellagic acid (EA), a polyphenol in PL extract, shows strong antioxidant, anti-aging, and anti-inflammatory properties and also plays a role in the treatment of various skin conditions. However, its role and mechanism of action in AGA remain unclear. AIM OF THE STUDY: To determine whether EA can rescue slow hair regeneration by regulating dihydrotestosterone (DHT)-induced ferroptosis in AGA mice and clarify the effect of EA on DHT-induced ferroptosis in dermal papilla cells (DPCs). MATERIALS AND METHODS: Male C57BL/6 mice were used to establish a DHT-induced AGA mouse model, whereas DPCs were used to establish a DHT-induced cellular model. Thereafter, we investigated the therapeutic mechanism of action of EA via immunofluorescence, western blot analysis, immunohistochemistry, electron microscopy, and molecular docking. RESULTS: EA stimulated hair regeneration in mice and reversed DHT-induced increases in iron content, lipid peroxidation, and DHT-induced mitochondrial dysfunction by activating the Wnt/ß-catenin signaling pathway. Further, ß-catenin knockdown suppressed the inhibitory effect of EA on DHT-induced ferroptosis in DPCs. CONCLUSION: EA inhibits DHT-induced ferroptosis and promotes hair regrowth in mice by activating the Wnt/ß-catenin signaling pathway. Thus, it has potential for use as a treatment option for AGA.

Transient stimulation of TRPMLs enhance the functionality of hDPCs and facilitate hair growth in mice.

Autophagy is essential for eliminating aging and organelle damage that maintaining cellular homeostasis. However, the dysfunction of autophagy has been proven in hair loss such as AGA. Despite the crucial role of TRPML channels in regulating autophagy, their specific function in hair growth remains unclarified. To investigate the biological functions and associated molecular mechanisms of TRPMLs in hair growth, Animal experiments were conducted to confirm the function of TRLMLs activation in promoting hair growth. Subsequently, we analyzed molecular mechanisms in human dermal papilla cells (hDPCs) activated by TRPMLs through transcriptome sequencing analysis. MLSA1(a TRPML agonist) promoted hair regeneration and accelerated hair cycle transition in mice. The activation of TRPMLs upregulated calcium signaling inducing hDPCs to secrete hair growth promoting factors and decrease hair growth inhibiting factors. In addition, activation of TRPMLs triggered autophagy and reduced the generation of ROS, thereby delaying the senescence of hDPCs. All these findings suggested that TRPMLs activation could promote hair growth by regulating hDPCs secretion of hair growth-related factors. Moreover, it may play a prominent role in preventing hDPCs from ROS damage induced by H2O2 or DHT. Targeting TRPMLs may represent a promising therapeutic strategy for treating hair loss.

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

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

Phloroglucinol Enhances Anagen Signaling and Alleviates H2O2-Induced Oxidative Stress in Human Dermal Papilla Cells.

Phloroglucinol (PG) is one of the abundant isomeric benzenetriols in brown algae. Due to its polyphenolic structure, PG exhibits various biological activities. However, the impact of PG on anagen signaling and oxidative stress in human dermal papilla cells (HDPCs) is unknown. In this study, we investigated the therapeutic potential of PG for improving hair loss. A non-cytotoxic concentration of PG increased anagen-inductive genes and transcriptional activities of ß-Catenin. Since several anagen-inductive genes are regulated by ß-Catenin, further experiments were performed to elucidate the molecular mechanism by which PG upregulates anagen signaling. Various biochemical analyses revealed that PG upregulated ß-Catenin signaling without affecting the expression of Wnt. In particular, PG elevated the phosphorylation of protein kinase B (AKT), leading to an increase in the inhibitory phosphorylation of glycogen synthase kinase 3 beta (GSK3ß) at serine 9. Treatment with the selective phosphoinositide 3-kinase/AKT inhibitor, LY294002, restored the increased AKT/GSK3ß/ß-Catenin signaling and anagen-inductive proteins induced by PG. Moreover, conditioned medium from PG-treated HDPCs promoted the proliferation and migration of human epidermal keratinocytes via the AKT signaling pathway. Subsequently, we assessed the antioxidant activities of PG. PG ameliorated the elevated oxidative stress markers and improved the decreased anagen signaling in hydrogen peroxide (H2O2)-induced HDPCs. The senescence-associated ß-galactosidase staining assay also demonstrated that the antioxidant abilities of PG effectively mitigated H2O2-induced senescence. Overall, these results indicate that PG potentially enhances anagen signaling and improves oxidative stress-induced cellular damage in HDPCs. Therefore, PG can be employed as a novel therapeutic component to ameliorate hair loss symptoms.

Dermal papilla cells cultured as spheres improve angiogenesis.

Tissue-engineered skin represents a helpful strategy for the treatment of deep skin injuries. Nevertheless, these skin substitutes must promote and encourage proper vascularization for a successful graft take. Previous work showed that dermal papilla cells (DPC) favour an earlier neovascularization process of grafted skin substitute contributing to the rapid maturation of the neovascular network, reducing inflammation and favouring extracellular matrix remodelling in nude mice. Based on these results, we studied the influence of DPC and its culture conditions on the different stages of angiogenesis in in vitro models. Here, we showed that DPC cultured as spheres favour the expression of angiogenic factors such as VEGF, FGF2 and angiogenin compared to their monolayer culture. To study the effects of DPC on the different stages of angiogenesis, an in vitro model has been adapted. DPC cultured as spheres significantly enhanced HUVEC migration and tubule formation, indicating the importance of employing physiological culture systems that provide a closer representation of cell behaviour and interactions occurring in vivo. Overall, these results allow us to speculate that the use of DPC spheres in skin substitutes could promote its grafting, vascularization and vascular network maturation through the secretion of angiogenic factors. This approach has great potential to improve clinical outcomes in regenerative medicine and skin wound repair.

Cardamonin-loaded liposomal formulation for improving percutaneous penetration and follicular delivery for androgenetic alopecia.

Androgenic alopecia (AGA) has a considerable impact on the physical and mental health of patients. Nano preparations have apparent advantages and high feasibility in the treatment of AGA. Cardamonin (CAR) has a wide range of pharmacological activities, but it has the problems of poor solubility in water and low bioavailability. There are few, if any, researches on the use of nano-loaded CAR to improve topical skin delivery of AGA. In this study, a CAR-loaded liposomal formulation (CAR@Lip and CAR@Lip Gel) was developed and characterized. The prepared CAR@Lip exhibited a uniform and rounded vesicle in size. CAR@Lip and CAR@Lip Gel can significantly improve the cumulative release of CAR. Additionally, CAR@Lip can obviously promote the proliferation and migration of human dermal papilla cells (hDPCs). Cell uptake revealed that the uptake of CAR@Lip significantly increased compared with the free drug. Furthermore, both CAR@Lip and CAR@Lip Gel groups could markedly improve the transdermal performance of CAR, and increase the topical content of the drug in the hair follicle compared with CAR. The ratchet effect of hair follicles could improve the skin penetration depth of nanoformulations. Notably, Anti-AGA tests in the mice showed that CAR@Lip and CAR@Lip Gel groups could promote hair growth, and accelerate the transition of hair follicles to the growth stage. The anti-androgen effect was revealed by regulating the expression of IGF-1, VEGF, KGF, and TGF-ß, participating in SHH/Gli and Wnt/ß-catenin pathways. Importantly, the nanoformulations had no obvious skin irritation. Thus, our study showed that CAR-loaded liposomal formulation has potential application in the treatment of AGA.

Keratin Microspheres as Promising Tool for Targeting Follicular Growth.

Skin is the body barrier that constrains the infiltration of particles and exogenous aggression, in which the hair follicle plays an important role. Recent studies have shown that small particles can penetrate the skin barrier and reach the hair follicle, making them a potential avenue for delivering hair growth-related substances. Interestingly, keratin-based microspheres are widely used as drug delivery carriers in various fields. In this current study, we pursue the effect of newly synthesized 3D spherical keratin particles on inducing hair growth in C57BL/6 male mice and in human hair follicle dermal papilla cells. The microspheres were created from partially sulfonated, water-soluble keratin. The keratin microspheres swelled in water to form spherical gels, which were used for further experiments. Following topical application for a period of 20 days, we observed a regrowth of hair in the previously depleted area on the dorsal part of the mice in the keratin microsphere group. This observation was accompanied by the regulation of hair-growth-related pathways as well as changes in markers associated with epidermal cells, keratin, and collagen. Interestingly, microsphere keratin treatment enhanced the cell proliferation and the expression of hair growth markers in dermal papilla cells. Based on our data, we propose that 3D spherical keratin has the potential to specifically target hair follicle growth and can be employed as a carrier for promoting hair growth-related agents.

ß-Nicotinamide Mononucleotide Promotes Cell Proliferation and Hair Growth by Reducing Oxidative Stress.

ß-Nicotinamide mononucleotide (NMN) has shown promising effects on intestinal health, and it is extensively applied as an anti-aging and Alzheimer's disease therapeutic, due to its medicinal properties. The effects of NMN on the growth of mouse hair were observed after hair removal. The results indicated that NMN can reverse the state of hair follicle atrophy, hair thinning, and hair sparsity induced by dihydrotestosterone (DHT), compared to that of minoxidil. In addition, the action mechanisms of NMN promoting hair growth in cultured human dermal papilla cells (HDPCs) treated with DHT were investigated in detail. The incubation of HDPCs with DHT led to a decrease in cell viability and the release of inflammatory mediators, including interleukin-6 (IL-6), interleukin-1Beta (IL-1ß) and tumor necrosis factor Alpha (TNF-α). It was found that NMN can significantly lower the release of inflammatory factors induced by DHT in HDPCs. HDPCs cells are protected from oxidative stress damage by NMN, which inhibits the NF-κB p65 inflammatory signaling pathway. Moreover, the levels of androgen receptor (AR), dickkopf-1 (DKK-1), and ß-catenin in the HDPCs were assessed using PCR, indicating that NMN can significantly enhance the expression of VEGF, reduced IL-6 levels and suppress the expression of AR and DKK-1, and notably increase ß-catenin expression in DHT-induced HDPCs.

ChIP-Seq analysis reveals PRKACB as a target gene of HOXC13 involved in rabbit hair follicle development.

Dermal papilla cells (DPCs) are key regulators of hair follicle (HF) development and growth, which not only regulate HF growth and cycling but play a role in the pathogenesis of hair loss. The transcription factor Homeobox C13 (HOXC13) can modulate the growth and development of HFs. Nevertheless, the specific genes and pathways regulated by HOXC13 in DPCs have yet to be determined. Thus, to gain a better understanding of genomic binding sites involved in HOXC13-regulated HF development, chromatin immunoprecipitation followed by high throughput sequencing (ChIP-Seq) was performed on rabbit DPCs with pcDNA3.1-3 × Flag-HOXC13 overexpression. A complete set of 9670 enrichment peaks was acquired by applying HOXC13-Flag ChIP. Subsequently, the peak sequence was annotated to the rabbit genome, revealing that 6.1 % of the peaks were identified within in the promoter region. Thereafter, five annotated genes were verified using RT-qPCR. The peak-associated genes were mainly enriched in signaling pathways related to HF development, such as MAPK and PI3K-Akt. Furthermore, by using a dual-luciferase reporter assay, we found that HOXC13 can target the protein kinase cAMP­dependent catalytic ß (PRKACB) promoter region (-1596 âˆ¼ -1107 bp) and inhibit its transcription, which was consistent with data obtained from ChIP-seq analysis. Overexpression of PRKACB gene significantly modulated the expression of BCL2, WNT2, LEF1, and SFRP2 genes related to HF development as determined by RT-qPCR (P < 0.01, P < 0.05). The CCK-8 and flow cytometry assays showed that PRKACB significantly inhibited the proliferation of DPCs and promoted apoptosis (P < 0.01). In conclusion, our research revealed that PRKACB has the potential to serve as a novel target gene of HOXC13, contributing to the regulation of the proliferation and apoptosis of DPCs. The process of identifying global target genes can contribute to the understanding of the intricate pathways that HOXC13 regulates in the growth of HFs.