Advances in Understanding Hair Growth

Melatonin promotes hair regeneration by modulating the Wnt/β-catenin signalling pathway

Melatonin (MLT) is a circadian hormone that reportedly influences the development and cyclic growth of secondary hair follicles; however, the mechanism of regulation remains unknown. Here, we systematically investigated the role of MLT in hair regeneration using a hair depilation mouse model. We found that MLT supplementation significantly promoted hair regeneration in the hair depilation mouse model, whereas supplementation of MLT receptor antagonist luzindole significantly suppressed hair regeneration. By analysing gene expression dynamics between the MLT group and luzindole-treated groups, we revealed that MLT supplementation significantly up-regulated Wnt/β-catenin signalling pathway-related genes. In-depth analysis of the expression of key molecules in the Wnt/β-catenin signalling pathway revealed that MLT up-regulated the Wnt/β-catenin signalling pathway in dermal papillae (DP), whereas these effects were facilitated through mediating Wnt ligand expression levels in the hair follicle stem cells (HFSCs). Using a DP-HFSCs co-culture system, we verified that MLT activated Wnt/β-catenin signalling in DPs when co-cultured with HFSCs, whereas supplementation of DP cells with MLT alone failed to activate Wnt/β-catenin signalling. In summary, our work identified a critical role for MLT in promoting hair regeneration and will have potential implications for future hair loss treatment in humans.

Refining the genomic profiles of North African sheep breeds through meta-analysis of worldwide genomic SNP data

Introduction

The development of reproducible tools for the rapid genotyping of thousands of genetic markers (SNPs) has promoted cross border collaboration in the study of sheep genetic diversity on a global scale.

Methods

In this study, we collected a comprehensive dataset of 239 African and Eurasian sheep breeds genotyped at 37,638 filtered SNP markers, with the aim of understanding the genetic structure of 22 North African (NA) sheep breeds within a global context.

Results and discussion

We revealed asubstantial enrichment of the gene pool between the north and south shores of the Mediterranean Sea, which corroborates the importance of the maritime route in the history of livestock. The genetic structure of North African breeds mirrors the differential composition of genetic backgrounds following the breed history. Indeed, Maghrebin sheep stocks constitute a geographically and historically coherent unit with any breed-level genetic distinctness among them due to considerable gene flow. We detected a broad east-west pattern describing the most important trend in NA fat-tailed populations, exhibited by the genetic closeness of Egyptian and Libyan fat-tailed sheep to Middle Eastern breeds rather than Maghrebin ones. A Bayesian FST scan analysis revealed a set of genes with potentially key adaptive roles in lipid metabolism (BMP2, PDGFD VEGFA, TBX15, and WARS2), coat pigmentation (SOX10, PICK1, PDGFRA, MC1R, and MTIF) and horn morphology RXFP2) in Tunisian sheep. The local ancestry method detected a Merino signature in Tunisian Noire de Thibar sheep near the SULF1gene introgressed by Merino's European breeds. This study will contribute to the general picture of worldwide sheep genetic diversity.

Potential application of PBM use in hair follicle organoid culture for the treatment of androgenic alopecia

Androgenic alopecia is a hereditary condition of pattern hair loss in genetically susceptible individuals. The condition has a significant impact on an individual's quality of life, with decreased self-esteem, body image issues and depression being the main effects. Various conventional treatment options, such as minoxidil, finasteride and herbal supplements, aim to slow down hair loss and promote hair growth. However, due to the chronic nature of the condition the financial cost of treatment for androgenic alopecia is very high and conventional treatment options are not universally effective and come with a host of side effects. Therefore, to address the limitations of current treatment options a novel regenerative treatment option is required. One promising approach is organoids, organoids are 3D cell aggregates with similar structures and functions to a target organ. Hair follicle organoids can be developed in vitro. However, the main challenges are to maintain the cell populations within the organoid in a proliferative and inductive state, as well as to promote the maturation of organoids. Photobiomodulation is a form of light therapy that stimulates endogenous chromophores. PBM has been shown to improve cell viability, proliferation, migration, differentiation and gene expression in dermal papilla cells and hair follicle stem cells. Therefore, photobiomodulation is a potential adjunct to hair follicle organoid culture to improve the proliferation and inductive capacity of cells.

Regulation of cashmere fineness traits by noncoding RNA in Jiangnan cashmere goats

BACKGROUND

Cashmere has long been used as the raw material for wool textiles. The diameter of the cashmere fibre determines its quality and economic value. However, the regulatory role of noncoding RNAs (ncRNAs) in cashmere fineness remains unclear, especially regarding the interaction between ncRNAs and coding RNAs.

RESULTS

Transcriptome sequencing was used to identify the expression profiles of long noncoding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) in the skin tissues of Jiangnan cashmere goats with different cashmere fineness levels. Integration analysis of ncRNA and coding RNA was performed in combination with previous research results. The results showed that 16,437 lncRNAs, 2234 circRNAs, and 1322 miRNAs were identified in 8 skin samples of cashmere goats. A total of 403 differentially expressed (DE) lncRNAs, 62 DE circRNAs and 30 DE miRNAs were identified in the skin tissues of the fine groups (Fe) and coarse groups (Ce). We predicted the target gene of DE lncRNA, the target gene of DE miRNA and the host gene of DE circRNA. Based on functional annotation and enrichment analysis of target genes, we found that DE lncRNAs could be involved in regulating the fineness traits of cashmere. The most potential lncRNAs were MSTRG.42054.1, MSTRG.18602.3, and MSTRG.2199.13.

CONCLUSIONS

The data from this study enriched the cashmere goat noncoding RNA database and helped to supplement the annotation of the goat genome. The results provided a new direction for the breeding of cashmere characters.

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

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

An oral French maritime pine bark extract improves hair density in menopausal women: A randomized, placebo-controlled, double blind intervention study

Background and Aims

Female pattern hair loss affects females of all ages with a trend to increase after menopause. This disorder may have significant psychological impact and lead to anxiety and depression.

Objective

In a single center, double blind, randomized, placebo-controlled study, the effects of oral Pycnogenol® intake (3 × 50 mg/day for a total of 6 months) on hair density, scalp microcirculation, and a variety of skin physiological parameters was studied in Han Chinese menopausal women (N = 76) in Shanghai, China.

Methods

Measurements were taken at the beginning and after 2 and 6 months, respectively. Hair density was determined by digital photographs and further evaluated by Trichoscan software. Transepidermal water loss was measured by a humidity sensor in a closed chamber on the skin surface. Changes in microcirculation were detected as resting flux on the scalp by reflection photoplethysmography.

Results

Pycnogenol® intake significantly increased hair density by 30% and 23% after 2 and 6 months of treatment, respectively, as detected by Trichoscan® evaluation of digital photographs. Interestingly, photoplethysmography revealed that this beneficial effect was associated with a decrease in resting flux of the scalp skin, which might indicate an improvement of microcirculation. None of these effects were observed in the placebo taking group. In addition, a significant transient decrease of transepidermal water loss was observed in scalp skin under Pycnogenol,® but not placebo treatment.

Conclusion

Oral intake of Pycnogenol® might have the potential to reduce hair loss in postmenopausal women.

Regulation of stem cell fate by HSPGs: implication in hair follicle cycling

Heparan sulfate proteoglycans (HSPGs) are part of proteoglycan family. They are composed of heparan sulfate (HS)-type glycosaminoglycan (GAG) chains covalently linked to a core protein. By interacting with growth factors and/or receptors, they regulate numerous pathways including Wnt, hedgehog (Hh), bone morphogenic protein (BMP) and fibroblast growth factor (FGF) pathways. They act as inhibitor or activator of these pathways to modulate embryonic and adult stem cell fate during organ morphogenesis, regeneration and homeostasis. This review summarizes the knowledge on HSPG structure and classification and explores several signaling pathways regulated by HSPGs in stem cell fate. A specific focus on hair follicle stem cell fate and the possibility to target HSPGs in order to tackle hair loss are discussed in more dermatological and cosmeceutical perspectives.

Perspectives on miRNAs Targeting DKK1 for Developing Hair Regeneration Therapy

Androgenetic alopecia (AGA) remains an unsolved problem for the well-being of humankind, although multiple important involvements in hair growth have been discovered. Up until now, there is no ideal therapy in clinical practice in terms of efficacy and safety. Ultimately, there is a strong need for developing a feasible remedy for preventing and treating AGA. The Wnt/β-catenin signaling pathway is critical in hair restoration. Thus, AGA treatment via modulating this pathway is rational, although challenging. Dickkopf-related protein 1 (DKK1) is distinctly identified as an inhibitor of canonical Wnt/β-catenin signaling. Thus, in order to stimulate the Wnt/β-catenin signaling pathway, inhibition of DKK1 is greatly demanding. Studying DKK1-targeting microRNAs (miRNAs) involved in the Wnt/β-catenin signaling pathway may lay the groundwork for the promotion of hair growth. Bearing in mind that DKK1 inhibition in the balding scalp of AGA certainly makes sense, this review sheds light on the perspectives of miRNA-mediated hair growth for treating AGA via regulating DKK1 and, eventually, modulating Wnt/β-catenin signaling. Consequently, certain miRNAs regulating the Wnt/β-catenin signaling pathway via DKK1 inhibition might represent attractive candidates for further studies focusing on promoting hair growth and AGA therapy.

Safety and efficacy of ALRV5XR in men with androgenetic alopecia: A randomised, double-blinded, placebo-controlled clinical trial

BACKGROUND

Androgenetic alopecia (AGA) is the most common hair loss disorder seen in men. It can have an early onset but has also been associated with ageing and senescence. It often induces pronounced psychological impact. ALRV5XR, a new hair loss treatment herein evaluated, was designed to target multiple molecular pathways involved in hair growth and hair follicle stem cell biology. The main objectives of the study were the assessment of safety and efficacy profiles of ALRV5XR in men.

METHODS

This 24-week, parallel randomised, placebo-controlled, double-blinded clinical trial was performed in a USA community clinic. Healthy men (age 22-65) with AGA and belonging to the Hamilton-Norwood (HN) classification I-VII and Fitzpatrick skin type (FST) I-VI, were randomly allocated in a 1:1 ratio into ALRV5XR or placebo treatment groups. Dermatologist assessment, phototrichograms, and blood samples were obtained in a blinded fashion at baseline, 12 and 24 weeks. Subjects were given a masked treatment consisting of oral capsules, shampoo, conditioner, and follicle serum, which was intended for daily use. Efficacy was assessed via absolute and per cent changes in terminal hair (TH) density, and response rates. The trial was registered with clinicaltrials.gov (NCT04450589) and is completed.

FINDINGS

Forty-six subjects were enroled in the study, 23 allocated to the ALRV5XR treatment and 23 to the placebo group. Enrolment occurred from April 11 to October 23, 2018. Thirty-six subjects completed the trial (17 ALRV5XR, 19 placebo) and 11 subjects in each group were evaluable for TH outcomes. At 24 weeks, the absolute change in TH density improved by 21·0 THs/cm² (95% CI: 9·2-32·8; p = 0·0014), and the relative density increased by 16·4% (95% CI: 7·4%-25·5%; p = 0·0012). The odds ratio for being a responder (≥ 0 change) was 87·4. TH density increased linearly and was not affected by HN, FST, ethnicity, age, or body mass index. All subjects in the ALRV5XR group responded to treatment while 81·8% of the placebo group decreased TH density. ALRV5XR induced statistically significant changes in both decrease in vellus hair (VH) density as well as in concomitant increase of the TH/VH ratio when compared to placebo. ALRV5XR was well tolerated, and no adverse events were observed.

INTERPRETATION

ALRV5XR treatment resulted in clinically significant TH regrowth in men with AGA. Furthermore, it appeared to reverse the characteristic hair miniaturisation seen in this condition. When compared to results of published trials of standard therapy, ALRV5XR showed a multi-fold increase both in efficacy and in response rates. In addition, the continuance of TH regrowth from 12 to 24 weeks suggests that the normal structure and function of non-productive telogen follicles is restored and that a normal hair phenotype may be attained by extended ALRV5XR treatment.

FUNDING

Arbor Life Labs.

An anti-hair loss treatment in the management of mild androgenetic alopecia: Results from a large, international observational study

Androgenic alopecia (AGA) is a common and chronic condition. It may impact self‐esteem, self‐image and quality of life. Benefit, tolerability, cosmetic acceptance and patient satisfaction are key to ensure good treatment outcome. Hair loss improvement and hair quality with AC5 (2,4‐Diamino‐Pyrimidine‐N‐Oxyde, arginine, 6‐O glucose linoleate (SP94), piroctone olamine and Vichy mineralizing water) once daily was assessed in 527 subjects with mild AGA in an open‐label, observational, international real‐life study. After 3 months, investigators evaluated the impact of AC5 on hair loss, product satisfaction and asked subjects about local tolerance; subjects assessed hair growth and quality and satisfaction. Data from 357 subjects were evaluable for the benefit analysis; 59.9% of subjects were female; the mean age was 33.6±8.7 years. Duration of hair loss was 1.62±2.24 years. 71.3% of women had a Ludwig score of 1 and 40.8% of men had a Hamilton Norwood score of 2. At the end of study, hair loss was reduced in 89.0% of subjects; it was slightly higher in women (92.5%) than in men (83.8%). Subject satisfaction on a scale from 0 (not satisfied at all) to 10 (completely satisfied) was 7.9±1.7. Tolerance was rated good to very good by 98.6% of all subjects. In conclusion, AC5 reduces mild AGA in both men and women with a pleasant texture. AC5 was well tolerated and highly appreciated.

Safety and efficacy of ALRV5XR in women with androgenetic alopecia or telogen effluvium: A randomised, double-blinded, placebo-controlled clinical trial

BACKGROUND

Scalp hair loss (alopecia) in women is a common ageing and senescing condition. It usually presents as androgenetic alopecia (AGA) or telogen effluvium (TE) and often has pronounced psychological consequences. ALRV5XR is a novel treatment aiming to regenerate a normal hair phenotype by targeting multiple molecular pathways linked to hair growth promotion and hair follicle stem cell activation. The primary objectives of this 24-week trial were to evaluate the safety and efficacy of ALRV5XR in terminal hair (TH) regrowth in women with AGA or TE.

METHODS

This randomised, double-blind, placebo-controlled trial was performed in a USA community clinic. Healthy women 18-65 years of age with AGA or TE of Ludwig classification I-II and Fitzpatrick skin type I-VI were enrolled. They were allocated in a 1:1 ratio into ALRV5XR or placebo treatment groups using a random number table. Masked dermatologist assessments, phototrichograms and blood samples were obtained at baseline, 12 and 24 weeks. Subjects were given a masked treatment regimen of oral capsules, shampoo, conditioner and follicle serum for daily administration. Main outcomes were absolute and per cent changes in TH density and response rates. The trial was registered with clinicaltrials.gov (NCT04450602) and is completed.

FINDINGS

46 subjects (23 ALRV5XR, 23 placebo) were enrolled between April 3 and October 20, 2018. Five subjects dropped out and two were non-compliant. Thirty-nine subjects completed the trial (18 ALRV5XR, 21 placebo). At 24 weeks, the absolute change in TH density improved by 30·1THs/cm² (95% CI: 15·1-45·1; p=0·0002), and the relative density increased by 19·7% (95% CI: 8·0%-31·4%; p=0·0016). The odds ratio for being a responder (≥0 change) was 2·7. Efficacy increased 133% from week 12 to 24. Efficacy outcomes were similar in AGA and TE subjects. 66·7% of the ALRV5XR group responded by regrowing 40THs/cm² or more hair. No adverse events were reported.

INTERPRETATION

In women with AGA or TE, ALRV5XR treatment significantly increased hair regrowth without adverse events. ALRV5XR displayed a multi-fold improved efficacy and response rate when compared to published trials of standard therapy. Progressive acceleration of TH regrowth suggests regeneration of the structure and function of non-productive telogen follicles and prolonged treatment may restore a normal hair phenotype.

Mapping of cis-acting expression quantitative trait loci in human scalp hair follicles

BACKGROUND

The association of molecular phenotypes, such as gene transcript levels, with human common genetic variation can help to improve our understanding of interindividual variability of tissue-specific gene regulation and its implications for disease.

METHODS

With the aim to capture the spectrum of biological processes affected by regulatory common genetic variants (minor allele frequency ≥ 1%) in healthy hair follicles (HFs) from scalp tissue, we performed a genome-wide mapping of cis-acting expression quantitative trait loci (eQTLs) in plucked HFs, and applied these eQTLs to help further explain genomic findings for hair-related traits.

RESULTS

We report 374 high-confidence eQTLs found in occipital scalp tissue, whose associated genes (eGenes) showed enrichments for metabolic, mitotic and immune processes, as well as responses to steroid hormones. We were able to replicate 68 of these associations in a smaller, independent dataset, in either frontal and/or occipital scalp tissue. Furthermore, we found three genomic regions overlapping reported genetic loci for hair shape and hair color. We found evidence to confirm the contributions of PADI3 to human variation in hair traits and suggest a novel potential candidate gene within known loci for androgenetic alopecia.

CONCLUSIONS

Our study shows that an array of basic cellular functions relevant for hair growth are genetically regulated within the HF, and can be applied to aid the interpretation of interindividual variability on hair traits, as well as genetic findings for common hair disorders.

'Omics' approaches for studying the microbiome in Alopecia areata

Nowadays, the involvement of the microbiome in human health and many human diseases, including that strictly related to the scalphas been brought to the light. Indeed, more recently, authors highlighted the presence of a significant microbial shift both in nonscarring (Androgenetic alopecia and Alopecia areata) and scarring Alopecias. The advent of novel technologies together with the effort of many scientists in the microbiome field could provide in the nearest future a clearest framework about the strict relationship between human healthiness and symbiotic microorganism resident on different ecosystem of our body. In this view, the use of Omics approaches has to be considered as no longer negligible when studying the microbiome implication in human health and disease.

Integral Roles of Specific Proteoglycans in Hair Growth and Hair Loss: Mechanisms behind the Bioactivity of Proteoglycan Replacement Therapy with Nourkrin® with Marilex® in Pattern Hair Loss and Telogen Effluvium

Follicular proteoglycans are key players with structural, functional, and regulatory roles in the growth and cycling behaviour of the hair follicles. The expression pattern of specific proteoglycans is strongly correlated with follicular phase transitions, which further affirms their functional involvement. Research shows that bioactive proteoglycans, e.g., versican and decorin, can actively trigger follicular phase shift by their anagen-inducing, anagen-maintaining, and immunoregulatory properties. This emerging insight has led to the recognition of “dysregulated proteoglycan metabolism” as a plausible causal or mediating pathology in hair growth disorders in both men and women. In support of this, declined expression of proteoglycans has been reported in cases of anagen shortening and follicular miniaturisation. To facilitate scientific communication, we propose designating this pathology “follicular hypoglycania (FHG),” which results from an impaired ability of follicular cells to replenish and maintain a minimum relative concentration of key proteoglycans during anagen. Lasting FHG may advance to structural decay, called proteoglycan follicular atrophy (PFA). This process is suggested to be an integral pathogenetic factor in pattern hair loss (PHL) and telogen effluvium (TE). To address FHG and PFA, a proteoglycan replacement therapy (PRT) program using oral administration of a marine-derived extract (Nourkrin® with Marilex®, produced by Pharma Medico Aps, Aarhus, Denmark) containing specific proteoglycans has been developed. In clinical studies, this treatment significantly reduced hair fall, promoted hair growth, and improved quality of life in patients with male- and female-pattern hair loss. Accordingly, PRT (using Nourkrin® with Marilex®) can be recommended as an add-on treatment or monotherapy in patients with PHL and TE.

CRH receptor antagonists from Pulsatilla chinensis prevent CRH-induced premature catagen transition in human hair follicles

BACKGROUND

There is a growing interest in the relationship among stress hormones, neuroendocrine signaling, and skin diseases, including hair loss. Previous reports showed that stress hormones inhibit human hair growth and induce early catagen transition. Moreover, a CRH receptor antagonist reversed CRH-induced alopecia in a mouse model, suggesting that antagonization of the CRH receptor is a key clinical strategy to treat stress-induced hair loss.

OBJECTIVES

The aim of this study was to investigate the protective effect of CRH receptor antagonists from Pulsatilla chinensis on human hair follicles (hHFs) and human dermal papilla cells (hDPCs).

METHODS

hHFs were observed and scored by hair cycle. The levels of cAMP, a second messenger, were measured in each group. In addition, the mRNA and protein levels of factors related to the hair cycle were measured. Furthermore, the expression levels of various members of the mitogen-activated protein kinase (MAPK) signaling pathway related to stress were measured.

RESULTS

CRH induced early catagen transition in an ex vivo hair organ culture model. In addition, CRH downregulated the levels of alkaline phosphatase (ALP) and hair anagen-related cytokines in cultured hDPCs. Moreover, CRH induced the phosphorylation of JNK, c-Jun, p38, ERK, and Akt in cultured hDPCs. CRH receptor antagonists isolated from P chinensis reversed these CRH-induced modulations in both ex vivo hair follicles (HFs) and cultured hDPCs.

CONCLUSIONS

These results indicate that P chinensis effectively blocks CRH receptor function and that saponin derivatives from P chinensis could be a pharmaceutical and cosmetic approach to treat stress-induced hair loss.

Laser-assisted Hair Regrowth: Fractional Laser Modalities for the Treatment of Androgenic Alopecia

Background:

A large proportion of the population is at sometime affected by androgenic alopecia. Current therapies consisting of minoxidil or finasteride are often the first choices for treatment. These regimens are limited by their efficacy, side-effect profiles, and often lengthy treatment courses. Low level laser/light has shown to be relatively effective and safe for the treatment of hair loss, and a number of products are currently available to consumers. Recently, fractional lasers have been examined as treatment options for androgenic alopecia. The mechanism of action of these minimally invasive resurfacing procedures is thought to be 2-fold. First, the microscopic injuries created by these treatments may induce a favorable wound healing environment that triggers hair growth. Alternatively, disruption of the stratum corneum allows for improved transdermal passage of well-established therapeutic drugs to the hair roots.

Methods:

A literature review was performed to evaluate the efficacy of these emerging treatments on hair regrowth.

Results:

Nine original studies examining the effect of fractional lasers on hair growth in androgenic alopecia have been reviewed.

Conclusions:

Preliminary evidence suggests that fractional laser therapies have a positive effect on hair regrowth; however, most of the literature is limited to case reports, and small prospective and retrospective series. Further studies, in the form of well-designed randomized controlled trials, are necessary to evaluate the efficacy, safety, and optimal treatment courses.

Effects of photoperiod on nutrient digestibility, hair follicle activity and cashmere quality in Inner Mongolia white cashmere goats

OBJECTIVE

This study investigated the effects of photoperiod on nutrient digestibility, hair follicle (HF) activity and cashmere quality in Inner Mongolia white cashmere goats.

METHODS

Twenty-four female (non-pregnant) Inner Mongolia white cashmere goats aged 1 to 1.5 years old with similar live weights (mean, 20.36±2.63 kg) were randomly allocated into two groups: a natural daily photoperiod group (NDPP group:10 to 16 h light, n = 12) and a short daily photoperiod group (SDPP group: 7 h light:17 h dark, n = 12). All the goats were housed in individual pens and fed the same diets from May 15 to October 15, 2015. The digestibility of crude protein (CP), dry matter (DM), and neutral detergent fiber (NDF) were measured in different months, along with secondary hair follicle (SHF) activity, concentration of melatonin (MEL), and cashmere quality.

RESULTS

Although there was no significant difference in the live weights of goats between the SDPP and NDPP groups (p>0.05), the CP digestibility of goats in the SDPP group was significantly increased compared to the NDPP group in July, September, and October (p<0.05). For the DM and NDF digestibility of goats, a significant increase (p<0.05) was found during in September in the SDPP group. Furthermore, compared to the NDPP group, the SHF activity in July, the MEL concentration in July, and the cashmere fiber length and fiber weight in October were significantly increased in the SDPP group (p<0.05).

CONCLUSION

The cashmere production of Inner Mongolia white cashmere goats was increased without obvious deleterious effects on the cashmere fibers in the SDPP group (metabolizable energy, 8.34 MJ/kg; CP, 11.16%; short daily photoperiod, 7 h light:17 h dark).

Annurca Apple Polyphenols Protect Murine Hair Follicles from Taxane Induced Dystrophy and Hijacks Polyunsaturated Fatty Acid Metabolism toward β-Oxidation

Chemotherapy-induced alopecia (CIA) is a common side effect of conventional chemotherapy and represents a major problem in clinical oncology. Even months after the end of chemotherapy, many cancer patients complain of hair loss, a condition that is psychologically difficult to manage. CIA disturbs social and sexual interactions and causes anxiety and depression. Synthetic drugs protecting from CIA and endowed with hair growth stimulatory properties are prescribed with caution by oncologists. Hormones, growth factors, morphogens could unwontedly protect tumour cells or induce cancer cell proliferation and are thus considered incompatible with many chemotherapy regimens. Nutraceuticals, on the contrary, have been shown to be safe and effective treatment options for hair loss. We here show that polyphenols from Malus Pumila Miller cv Annurca are endowed with hair growth promoting activity and can be considered a safe alternative to avoid CIA. In vitro, Annurca Apple Polyphenolic Extract (AAE) protects murine Hair Follicles (HF) from taxanes induced dystrophy. Moreover, in virtue of its mechanism of action, AAE is herein proven to be compatible with chemotherapy regimens. AAE forces HFs to produce ATP using mitochondrial β-oxidation, reducing Pentose Phosphate Pathway (PPP) rate and nucleotides production. As consequence, DNA replication and mitosis are not stimulated, while a pool of free amino acids usually involved in catabolic reactions are spared for keratin production. Moreover, measuring the effect exerted on Poly Unsaturated Fatty Acid (PUFA) metabolism, we prove that AAE promotes hair-growth by increasing the intracellular levels of Prostaglandins F2α (PGF2α) and by hijacking PUFA catabolites toward β-oxidation.

Annurca Apple Polyphenols Ignite Keratin Production in Hair Follicles by Inhibiting the Pentose Phosphate Pathway and Amino Acid Oxidation

Patterned hair loss (PHL) affects around 50% of the adult population worldwide. The negative impact that this condition exerts on people’s life quality has boosted the appearance of over-the-counter products endowed with hair-promoting activity. Nutraceuticals enriched in polyphenols have been recently shown to promote hair growth and counteract PHL. Malus pumila Miller cv. Annurca is an apple native to Southern Italy presenting one of the highest contents of Procyanidin B2. We have recently shown that oral consumption of Annurca polyphenolic extracts (AAE) stimulates hair growth, hair number, hair weight and keratin content in healthy human subjects. Despite its activity, the analysis of the molecular mechanism behind its hair promoting effect is still partially unclear. In this work we performed an unprecedented metabolite analysis of hair follicles (HFs) in mice topically treated with AAE. The metabolomic profile, based on a high-resolution mass spectrometry approach, revealed that AAE re-programs murine HF metabolism. AAE acts by inhibiting several NADPH dependent reactions. Glutaminolysis, pentose phosphate pathway, glutathione, citrulline and nucleotide synthesis are all halted in vivo by the treatment of HFs with AAE. On the contrary, mitochondrial respiration, β-oxidation and keratin production are stimulated by the treatment with AAE. The metabolic shift induced by AAE spares amino acids from being oxidized, ultimately keeping them available for keratin biosynthesis.

Crocin, a natural molecule with potentially beneficial effects against skin ageing

OBJECTIVE

Oxidative stress and low-grade chronic inflammation stand out as key features of physiological skin ageing. The aim of this study was to examine in normal human epidermal keratinocytes (NHEK) and human dermal fibroblasts (HDF) grown in vitro, the antioxidant and anti-inflammatory properties of crocin, a carotenoid glycoside responsible for the colour of saffron. Moreover, considering the newly emerging field of skin glycobiology and the presence of two gentiobiosyl moieties in crocin, the effect of crocin on NHEK glycosylation pathways was for the first time investigated.

METHODS

The anti-inflammatory and antioxidant activities of crocin were evaluated by in vitro assays of antioxidation activities, ELISA and microarray analysis. The effect of crocin on keratinocyte glycobiology was evaluated by proprietary GLYcoDiag lectin technologies and microarray analysis.

RESULTS

Crocin is endowed with antioxidant potential against reactive oxygen species, protects squalene against UVA-induced peroxidation and prevents the release of inflammatory mediators. The expression of NF-kB-related genes and glycosylation-related genes is modulated in the presence of crocin.

CONCLUSION

Results could designate this molecule as a promising skin ageing prevention cosmetic agent. Of note, some of these effects could be mediated by protein O-glycosylation and interaction of crocin with osidic receptors of keratinocytes.

Skin transcriptome reveals the intrinsic molecular mechanisms underlying hair follicle cycling in Cashmere goats under natural and shortened photoperiod conditions

The growth of cashmere exhibits a seasonal pattern arising from photoperiod change. However, the underlying molecular mechanism remains unclear. We profiled the skin transcriptome of six goats at seven time points during hair follicle cycling via RNA-seq. The six goats comprised three goats exposed to a natural photoperiod and three exposed to a shortened photoperiod. During hair cycle transition, 1713 genes showed differential expression, and 332 genes showed a pattern of periodic expression. Moreover, a short photoperiod induced the hair follicle to enter anagen early, and 246 genes overlapped with the periodic genes. Among these key genes, cold-shock domain containing C2 (CSDC2) was highly expressed in the epidermis and dermis of Cashmere goat skin, although its function in hair-follicle development remains unknown. CSDC2 silencing in mouse fibroblasts resulted in the decreased mRNA expression of two key hair-follicle factors, leading to reduced cell numbers and a lower cell density. Cashmere growth or molting might be controlled by a set of periodic regulatory genes. The appropriate management of short light exposure can induce hair follicles to enter full anagen early through the activation of these regulators. The CSDC2 gene is a potentially important transcription factor in the hair growth cycle.

Conventional and novel stem cell based therapies for androgenic alopecia

The prevalence of androgenic alopecia (AGA) increases with age and it affects both men and women. Patients diagnosed with AGA may experience decreased quality of life, depression, and feel self-conscious. There are a variety of therapeutic options ranging from prescription drugs to non-prescription medications. Currently, AGA involves an annual global market revenue of US$4 billion and a growth rate of 1.8%, indicating a growing consumer market. Although natural and synthetic ingredients can promote hair growth and, therefore, be useful to treat AGA, some of them have important adverse effects and unknown mechanisms of action that limit their use and benefits. Biologic factors that include signaling from stem cells, dermal papilla cells, and platelet-rich plasma are some of the current therapeutic agents being studied for hair restoration with milder side effects. However, most of the mechanisms exerted by these factors in hair restoration are still being researched. In this review, we analyze the therapeutic agents that have been used for AGA and emphasize the potential of new therapies based on advances in stem cell technologies and regenerative medicine.

Pregnancy and the hair growth cycle: anagen induction against hair growth disruption using Nourkrin® with Marilex® , a proteoglycan replacement therapy

Postpartum effluvium is a well-known clinical fact. However, following some minor research activities in the 1960s, very little has happened on the research front of the subject. It was hypothesized that postpartum hair loss might be a manifestation of a change in the hair growth cycle occurring normally during pregnancy. Recently, new research has been published trying to explain the mechanism of action behind this frequently occurring hair growth disruption, and to develop a functional treatment schedule and regime. Under normal circumstances, postpartum effluvium will disappear by itself as a function of time, and therefore adequate information to the patient is important in order to reduce the anxiety that it will not be a permanent problem. However, in some subjects it can manifest itself for longer stages and even become permanent. At the present time, treatments aim at correcting underlying hormonal imbalances and at improving overall cosmetic appearance. Several treatments in the form of thyroid supplementation, topical progesterone and estradiol lotions, and even oral contraceptive have been studied. All the available studies have significant limitations in their scientific basis, such as small sample size, absence of control group, or highly subjective measurement of treatment response. It is evident from the available studies that no specific treatment has been investigated thoroughly enough to justify recommendation in clinical treatment or to be termed "effective." Without the ability to provide a pathogenic diagnosis or causality criteria, chances are low that a treatment by trial and error will adequately be able to control hair effluvium. Current hair treatment strategies are symptomatic and nonspecific; therefore, future research must aim at developing new and targeted methods with a point of departure in observing concomitant biological mechanisms. Based on the research in the 1960s, current knowledge about the hair follicle and the regulation of the hair cycles, we believe that an anagen inducer in the form of a specific proteoglycan replacement therapy (Nourkrin^® with Marilex^® from Pharma Medico) could be a proper solution to shorten the hair eclipse phenomenon - and give the patient a feeling of control and empowerment.