Telogen Phase Research Articles

Investigation of Wrightia tinctoria extract activity on Alopecia using In-silco and In-vivo studies

There are many drugs for alopecia such as minoxidil, glucocorticoids, sulfasalazine, nitric oxide, and vitamin D3. Hair loss is also known as alopecia, or baldness commonly refers to hair loss from either a portion of a head or body. Fresh Leaves, and bark from twigs of Wrightia tinctoria were taken and used for extraction. A phytochemical assessment was continued to carry out on W.tinctoria extract and the presence of aromatic hydrogen and aromatic protons was demonstrated by spectral characterization. Insilco studies were done. Compounds 1and6 shown more docking values than the minoxidil and Swiss ADME confirmed that the compounds can enter the blood-brain barrier and not the substrates of PgP carriers. In vivo evaluation of alopecia activity using albino male, Wistar rats were done by comparing it with standard drug involves the evaluation of in vivo hair development activities of W.tinctoria extract. It also involves histopathological studies which include the action of hair growth at anagen and telogen phases on 15th and 30th day. The study indicates that the material elements of W.tinctoria which include Quercetin and Indirubin playing a critical role in hair promoting activity.

Histological Analysis for the Cause of Kinky Hair after Hair Transplantation

<i><b>Introduction:</b></i> Studies on kinky hair after hair transplantation are rare although kinky hair happens frequently. Commonly referred to in the literature as “post-transplant kinkiness,” we decided to investigate what causes kinky hair using a histologic approach. <i><b>Method:</b></i> A patient, who had a hair transplant at another clinic three years previously, came to our clinic with a complaint of low density of transplanted area. Reduction foreheadplasty was done to reduce the height of her forehead as well as to get rid of low-density parts. We collected some of the severe kinky hairs upon the removal of transplanted areas and observed them at the microscopic level. <i><b>Results:</b></i> We noted fibrotic tissues alongside the kinky hair’s follicle. In addition, distortion of the bulb was observed with the presence of fibrotic tissue at the subcutaneous layer. <i><b>Discussion:</b></i> We usually mention scarring in terms of kinky hair after transplantation. Scars in the subcutaneous layer probably cause kinky hair rather than scars in the dermis. Fibrotic tissue that forms in the subcutaneous layer presses on transplanted hair follicles and causes deformity of follicles. Growing follicles after the telogen phase are likely to be deformed by encountering scar tissue when they grow downward to enter the anagen phase. The resulting deformed bulb causes the kinky hair. Therefore, reducing tissue damage during transplantation is very important. Inflammation aggravates scar formation, so it might be helpful to lessen the factors that lead to inflammation such as infection and bleeding. <i><b>Conclusion:</b></i> Perifollicular scarring after hair transplantation causes hair follicle deformity and results in the hairs growing as kinky hair. Therefore, reducing scarring in the transplant recipient area is essential for the prevention of kinky hair.

A Summary of Pre-Clinical and Clinical Evidence for Cannabinoid Hair Follicle Effects

The endocannabinoid system (ECS), discovered in the 1990s, is a system involved with maintaining cellular homoeostasis by down-regulating the damaging inflammatory responses and upregulating regenerative processes. Tetrahydrocannabinol (THC), Cannabidiol (CBD), tetrahydrocannabivarin (THCV) and cannabidivarin (CBDV) are all phytocannabinoids that have novel therapeutic effects on hair growth through the ECS receptors on hair follicles. These cannabinoids are fat-soluble and poorly absorbed past the epidermis, but topical application easily reaches hair follicles where CBDV, THCV and CBD act as partial or full CB1 antagonists and agonists of vanilloid receptor-1 (TRPV1) and vanilloid receptor-4 (TRPV4). All these ECS receptors relate to hair follicle function. THC on the other hand has the opposite effects decreasing hair shaft elongation and matrix production. A summary of the pre-clinical and clinical cannabinoid research is reviewed. The studies confirm that for androgenetic alopecia (AGA) the method of action is different from and synergistic with current hair regrowth therapies. Blocking the CB1 receptor on the hair follicle has been shown to result in hair shaft elongation and matrix production via keratinocytes, in addition, the hair follicle cycle (anagen, catagen, and telogen phases) is controlled by TRPV1. The effects of CBD on hair growth are dose dependent and higher doses may result in premature entry into the catagen phase via a different receptor known as TRPV4. CBD has also been shown to increase Wnt signaling, which causes dermal progenitor cells to differentiate into new hair follicles and maintains anagen phase of the hair cycle. Two recent six-month duration clinical trials of adults with androgenetic alopecia (AGA) have revealed an average 93.5% increased hair count with CBD alone, and 164% increased hair count with hemp extract high in CBD, THCV, CBDV and menthol. A current study is underway to look at punch biopsies of the areas of hair regrowth in patients treated with a combination of CBD, THCV isolate, menthol and caffeine. Another study is underway looking at using hexahydrocannabinol (HHC) a hydrogenated version of THC to decrease facial hair growth as a cosmetic effect

Epidemiology and Treatment of Male Androgenetic Alopecia

Hair loss affects self-image and is a significant contributor to anxiety and depression in some men, despite the fact that male androgenetic alopecia is frequently thought of as a relatively minor dermatological problem. Male androgenetic alopecia is also considered a risk factor for several other diseases including cardiovascular diseases. It affects 30-50% of men by the age of 50. Male androgenetic alopecia is a genetically transferred disease. Midfrontal scalp, vertex and temples are the commonly affected areas. Follicular shrinkage, inflammation, and altered hair development are the main pathophysiological characteristics the disease. The anagen phase gets shorter with each cycle whereas the telogen phase stays the same length or gets longer during the course of the disease. The purpose of this research is to review the available information about the epidemiology and treatment of male androgenetic alopecia. Male androgenetic alopecia shows variable prevalence among different ages and ethnicities. Caucasians have much high reported prevalence than Asians. The prevalence of male androgenetic increases with age. Minoxidil and finasteride are the drugs of choice and most commonly used in practice for the treatment. Even while the existing therapies for androgenetic alopecia are effective in slowing the disease's progression, they only allow for partial hair restoration. Early treatment leads to the most ideal outcome. Hair transplantation remains the option if medical treatment fails. Further research can aid in developing new treatment strategies.

СРАВНИТЕЛЬНЫЙ АНАЛИЗ ВЛИЯНИЯ ИНФЕКЦИИ COVID-19 И ОБЩЕСОМАТИЧЕСКИХ ЗАБОЛЕВАНИЙ НА ТЕЛОГЕНОВОЕ ВЫПАДЕНИЕ ВОЛОС

of performing urgent military service who were treated for general somatic diseases (n = 151), coronovirus infection (n = 50) caused by COVID­19, and healthy individuals (n = 50). The relationship of general somatic diseases and coronovirus infection COVID­19 with telogen hair loss in the study population was studied. The relationship between temperature and body mass index and telogen hair loss has been established. Analysis of the data obtained showed that even with a mild course of the underlying disease, an accelerated transition from the anagen phase of hair growth to the telogen phase can be observed in 12 %, and in the group with COVID­19 infection, such a transition was observed in 94.0 % of patients.

Assessment of the Oxidative Stress Status in Androgenetic Alopecia in Egyptian Men

Abstract Background Androgenetic alopecia (AGA) is the most common type of hair loss in men. It is commonly known as a male pattern baldness. It is characterized by a stepwise miniaturization of the hair follicle, resulting from alteration in the hair cycle dynamics, leading to vellus transformation of terminal hair follicle. In AGA, the duration of anagen phase gradually decreases and that of telogen phase increases, the maximum length of the new anagen hair becomes shorter than that of its predecessor, leading to miniaturization and eventually a bald appearance. Aim of the Work To assess the expression of NRF2 in the scalp of men with androgenetic alopecia. Patients and Methods This case control study included 28 male patients whose age ranged from 18 to 45 years old. They were diagnosed as having AGA according to Norwood-Hamilton scale. Further, 28 age and sex matched healthy male controls were recruited. All patients and controls were recruited from the dermatology outpatient clinic of Ain-Shams University Hospitals, during the period of September 2018 to April 2019. Results A group of Twenty-eight male patients with AGA were recruited to the study. The of patients ranged from 18 to 45 years (mean = 33.46 years ± 9.9 SD). Twenty-eight age matched male healthy volunteers without AGA were e recruited. The majority of AGA patients had positive family history of AGA in their first degree relatives. None of our patients had a medical history of systemic diseases like diabetes mellitus or hypertension. Conclusion The current study showed that alteration of Nrf2 levels may play an important role in the pathogenesis of AGA.

Assessment of Human Nuclear Factor Erythroid 2 Related Factor 2 (NRF2) in Androgenetic Alopecia in Egyptian Men

Abstract Background Androgenetic alopecia (AGA) is the most common type of hair loss in men. It is commonly known as a male pattern baldness. It is characterized by a stepwise miniaturization of the hair follicle, resulting from alteration in the hair cycle dynamics, leading to vellus transformation of terminal hair follicle. In AGA, the duration of anagen phase gradually decreases and that of telogen phase increases, the maximum length of the new anagen hair becomes shorter than that of its predecessor, leading to miniaturization and eventually a bald appearance. Aim of the work To assess the expression of NRF2 in the scalp of men with androgenetic alopecia. Patients and Methods This case control study included 28 male patients whose age ranged from 18 to 45 years old. They were diagnosed as having AGA according to Norwood-Hamilton scale. Further, 28 age and sex matched healthy male controls were recruited. All patients and controls were recruited from the dermatology outpatient clinic of Ain-Shams University Hospitals, during the period of September 2018 to April 2019. Results A group of Twenty-eight male patients with AGA were recruited to the study. The of patients ranged from 18 to 45 years (mean = 33.46 years ± 9.9 SD). Twenty-eight age matched male healthy volunteers without AGA were e recruited. The majority of AGA patients had positive family history of AGA in their first degree relatives. None of our patients had a medical history of systemic diseases like diabetes mellitus or hypertension. Conclusion The current study showed that alteration of Nrf2 levels may play an important role in the pathogenesis of AGA.

Chronic telogen effluvium in women

Background Chronic telogen effluvium (CTE) is a form of diffuse hair loss in middle-aged women in whom telogen hair loss continues more than 6 months without obvious etiology. Disturbance in growth hair cycle may result in increased hairs in the telogen phase. Micronutrient deficiency, such as iron, zinc, and vitamin D, has been incriminated in acute telogen effluvium but its role in chronic phases is challenging. Objective To measure the levels of serum ferritin, zinc, and 25-hydroxy vitamin D (25OH vitamin D) in females with CTE and controls to verify their role in hair-loss pathogenesis. Patients and methods A case–control study was conducted on 166 female participants: 83 patients with CTE and 83 age-matched healthy controls. Blood samples were taken from all participants for evaluation of serum ferritin, zinc, and 25OH vitamin D levels. Ferritin and 25OH vitamin D levels were measured with chemiluminescence method and zinc level was measured with colorimetric method. The study was done during 6 months (autumn and winter). Results There was no significant difference in serum ferritin, zinc, and 25OH vitamin D levels in two groups. The median of ferritin level was suboptimal in both groups (≤40 μg/l). Interestingly, zinc and 25OH vitamin D levels in healthy participants were lower than patients with CTE, but with considering the significance level of 0.01, this difference was not significant. The frequency of suboptimal levels of ferritin, 25OH vitamin D, and zinc was not significantly different in two groups. Conclusion We found no significant difference in ferritin, 25OH vitamin D, and zinc levels in two groups, but the role of these micronutrients in CTE could not be ignored. It seems that suboptimal levels of ferritin and 25OH vitamin D in women are common and may have led this non significant difference.

Suppression of FGF5 and FGF18 Expression by Cholesterol-Modified siRNAs Promotes Hair Growth in Mice

FGF5 and FGF18 are key factors in the regulation of the hair follicle cycle. FGF5 is overexpressed during the late anagen phase and serves as a crucial regulatory factor that promotes the anagen-to-catagen transition in the hair follicle cycle. FGF18, which is overexpressed during the telogen phase, mainly regulates the hair follicle cycle by maintaining the telogen phase and inhibiting the entry of hair follicles into the anagen phase. The inhibition of FGF5 may prolong the anagen phase, whereas the inhibition of FGF18 may promote the transition of the hair follicles from the telogen phase to the anagen phase. In the present study, we used siRNA to suppress FGF5 or FGF18 expression as a way to inhibit the activity of these genes. Using qPCR, we showed that FGF5-targeting siRNA modified by cholesterol was more effective than the same siRNA bound to a cell-penetrating peptide at suppressing the expression of FGF5 both in vitro and in vivo. We then investigated the effects of the cholesterol-modified siRNA targeting either FGF5 or FGF18 on the hair follicle cycle in a depilated area of the skin on the back of mice. The cholesterol-modified siRNA, delivered by intradermal injection, effectively regulated the hair follicle cycle by inhibiting the expression of FGF5 and FGF18. More specifically, intradermal injection of a cholesterol-modified FGF5-targeted siRNA effectively prolonged the anagen phase of the hair follicles, whereas intradermal injection of the cholesterol-modified FGF18-targeted siRNA led to the mobilization of telogen follicles to enter the anagen phase earlier. The inhibitory effect of the cholesterol-modified FGF18-targeted siRNA on FGF18 expression was also evaluated for a topically applied siRNA. Topical application of a cream containing the cholesterol-modified FGF18-targeted siRNA on a depilated area of the skin of the back of mice revealed comparable inhibition of FGF18 expression with that observed for the same siRNA delivered by intradermal injection. These findings suggested that alopecia could be prevented and hair regrowth could be restored either through the intradermal injection of cholesterol-modified siRNA targeting FGF5 or FGF18 or the topical application of FGF18 siRNA.

Case Study of Hair Regrowth with Topical Cannabidiol (CBD)

<h3>Introduction:</h3> Discovered in the 1990s, the endocannabinoid system (ECS) is involved with maintaining cellular homeostasis by downregulating the damaging inflammatory response and upregulating regenerative processes. Cannabidiol (CBD) has novel therapeutic effects, different from and synergistic with current hair regrowth therapies. CBD is fat-soluble and poorly absorbed past the epidermis, but topical application of CBD easily reaches hair follicles where it is a CB1 antagonist and agonist of vanilloid receptor-1 (TRPV1) and vanilloid receptor-4 (TRPV4). All these ECS receptors relate to hair follicle function. Blocking the CB1 receptor on the hair follicle with CBD has been shown to result in hair shaft elongation; in addition, the hair follicle cycle (anagen, catagen, and telogen phases) is controlled by TRPV1. The effects of CBD on hair growth are dose dependent and higher doses may result in premature entry into the catagen phase via a different receptor known as TRPV4. CBD has also been shown to increase Wnt signaling, which causes dermal progenitor cells to differentiate into new hair follicles and maintains anagen phase of the hair cycle. <h3>Objective:</h3> This study was conducted to determine if daily topical application of a hemp oil high in CBD concentration would result in significant hair regrowth in the area of the scalp most affected by androgenetic alopecia (AGA). <h3>Methods:</h3> A study was done of 35 (28 men and 7 women) subjects with AGA. Participants used a once daily topical CBD formulation, averaging about 3-4mg per day for 6 months. A hair count of the greatest area of alopecia was carried out before treatment started and after 6 months of treatment. To facilitate consistent hair count analysis, a clear acrylic mold, containing a 1cm² cutout, was made of each subject’s head. <h3>Results:</h3> The results revealed that men did slightly better than women, and the vertex area did better than the temporal areas. On average, there was a statistically significant 93.5% increase in nonvellus hair after 6 months of once daily use. All subjects had some regrowth. There were no reported adverse effects. <h3>Discussion:</h3> Though the exact mechanism of therapeutic effects is not known, CBD is most likely functioning as a CB1 receptor antagonist and potentially also via Wnt messaging. Topical CBD formulation has comparable results to finasteride and comparable results to 5% minoxidil once daily foam. Since the CBD works through novel mechanisms different from finasteride and minoxidil, it can be used in conjunction with these current drugs and would be expected to have synergistic effects. However, safety of this combination would need to be evaluated.

Hair Growth Promotion by δ-Opioid Receptor Activation.

Literature has revealed that the delta opioid receptor (DOR) exhibited diverse pharmacological effects on neuron and skin. In the present study, we have investigated whether the activation of DOR has hair-growth promotion effects. Compared with other opioid receptor, DOR was highly expressed in epidermal component of hair follicle in human and rodents. The expression of DOR was high in the anagen phase, but it was low in the catagen and telogen phases during mouse hair cycle. Topical application of UFP-512, a specific DOR agonist, significantly accelerated the induction of the anagen in C3H mice. Topical application of UFP-512 also increased the hair length in hair organ cultures and promoted the proliferation and the migration of outer root sheath (ORS) cells. Similarly, pharmacological inhibition of DOR by naltrindole significantly inhibited the anagen transition process and decreased hair length in hair organ cultures. Thus, we further examined whether Wnt/β-catenin pathway was related to the effects of DOR on hair growth. We found that Wnt/β-catenin pathway was activated by UFP-512 and siRNA for β-catenin attenuated the UFP-512 induced proliferation and migration of ORS cells. Collectively, result established that DOR was involved in hair cycle regulation, and that DOR agonists such as UFP-512 should be developed for novel hair-loss treatment.

The Significance of Serum Ferritin and vitamin D Levels in Females Patients with Chronic Telogen Effluvium

Back ground : Diffuse hair loss is a very common complaint usually occurs without inflammation or scarring.The loss affects hairs throughout the scalp in a more or less uniform pattern . That is characterized by theingress of a large number of hairs prematurely into telogen phase resulting in diffuse hair shedding at onetime often with an acute onset so named acute telogen effluvium .A chronic form with a more insidious onsetand a longer duration also exists called chronic telogen effluvium which primarily affects women betweenthe ages of 30 and 60 years and is a diagnosis of exclusion and can cause a great psychological impact onthe life of the affected person.Objective: Measurement the level of serum ferritin and the level of serum vitamin D In adult females withchronic telogen effluvium in order to validate their role in the process of hair loss .Patients&amp; Methods : This cross-sectional study was conducted at the outpatient Department of Dermatologyand Venereology in Al-kindy Teaching Hospital between March and November 2017.Sixty adult Female atage (12 to 52 years) with hair loss in the form of CTE otherwise they are healthy and sixty adult healthy withsame age-matched female with no hair loss were included in the study. Diagnosis was based upon clinicalexamination as well as hair pull test. Serum ferritin and vitamin D levels and Hemoglobin were determinedfor each participant .Results : Hair loss can have an emotional impact on patients leading to anxiety and frustration. Therefore,diagnosing the underlying etiology is necessary for the better management of the disorder The results of thisstudy suggest that the reduced hair density seen in CTE may possibly be associated with low serum levelsof ferritin and vitamin D. It is recommended that hemoglobin level measurement should not be solely reliedon in the assessment of hair loss, as it was not significantly different between patients with CTE and controlsas seen in our study.Conclusions: The female cases in this study had significantly low levels of serum ferritin and vitamin D thancontrols .Our study highlights the importance of serum ferritin and vitamin D evaluation in case of diffusehair fall.

Effects of UV Induced-Photoaging on the Hair Follicle Cycle of C57BL6/J Mice.

PurposeTo study the changes in the hair follicle cycle and related stem cells induced by photoaging to establish a mouse model of senescence in hair follicles.MethodsThere were 54 C57BL6/J mice randomly divided into three groups. The UVA group and the UVB group underwent photoaging induced by UV lamps for 8 weeks. Changes in skin and the hair follicle cycle were compared by physical signs, dermoscopy, and hematoxylin and eosin and Masson’s staining in each group. Western blot, immunohistochemistry, and RT-qPCR were carried out to test canonical proteins and gene expression of the Wnt signaling pathway in the samples. Immunofluorescence was chosen to show variations in the stem cells related to the hair follicle cycle.ResultsThere were more gray hairs in the UVA group than the other groups (P<0.05). Both diameter of the hair shaft and depth of hair root were significantly decreased in the UV groups (P<0.05). Stem cells and melanocytes of the hair follicles were reduced in the UVA group. UV, especially UVB, up-regulated the expression of the Wnt signaling pathway and prolonged anagen and telogen phases in the hair follicles, compared with the control group (P<0.05).ConclusionBy decreasing the number of stem cells related to hair follicles, UVA induces hair follicle photoaging characterized by hair follicle miniaturization and gray hairs. UV up-regulated the expression of the Wnt signaling pathway, and the hair follicle cycle was significantly prolonged by UVB.

Efficacy of Cetirizine 1% Versus Minoxidil 5% Topical Solution in the Treatment of Male Alopecia: A Randomized, Single-blind Controlled Study

Prostaglandins play a pivotal role in modulating hair growth cycle. Prostaglandin F2α and prostaglandin E have stimulating and prostaglandin D has inhibitory effects on hair follicle. Cetirizine inhibits release of prostaglandin D2 and stimulates the release of prostaglandin E2. In the present study, the efficacy and safety of twice daily application of topical cetirizine 1% versus minoxidil 5% solutions for 16 weeks were compared in male androgenetic alopecia (AGA). Forty men, aged 18 to 49 years, ‎were randomly divided into two equal groups to apply either cetirizine 1% or minoxidil 5% solutions. The study was divided into two phases, a 16-week treatment phase either with cetirizine or minoxidil (anagen phase), followed by an 8-week ‎ drug-free (telogen phase) with a follow-up when patients used placebo. Efficacy outcomes included the change in total hair density, vellus and terminal hair density, hair diameter and the percentage of hair in anagen and telogen phases from baseline in 16 and 24 weeks. After 16 weeks, we observed a significant increase in total and vellus hair density in both minoxidil and cetirizine groups, but the improvement was much higher in the minoxidil group. The percentage of hair in the anagen phase also increased in both groups after 16 weeks of treatment, but then diminished after 8 weeks of placebo consumption. No significant adverse reactions associated with the administration of cetirizine solution were reported. Cetirizine 1% solution was effective in hair growth without any complications for treatment of male AGA.

581 Hair histology and glycosaminoglycans distribution probed by infrared spectral imaging: Focus on heparan sulfate proteoglycan and glypican-1 during hair growth cycle

Heparan sulfate proteoglycans (HSPGs) distribution in hair follicle (HF) is classically investigated by conventional histology, biochemical analysis, and immunohistochemistry. In this study, a novel approach is proposed to assess hair histology and HSPG distribution changes in the HF at different phases of the hair growth cycle using infrared spectral imaging (IRSI). Particularly, we were interested in the expression of glypican-1 in different HF compartments and their potential roles during hair shaft growth, as their roles are still poorly understood. The distribution of HSPGs in HFs was probed by IRSI using the absorption region relevant to sulfation as a spectral marker. Findings were supported by Western immunoblotting and immunohistochemistry assays focusing on the glypican-1 expression and distribution in HFs. This study demonstrates the capacity of IRSI to identify the different HF tissue structures and to highlight protein, proteoglycan (PG), glycosaminoglycan (GAG), and sulfated GAG distribution in these structures. The comparison between anagen, catagen, and telogen phases shows the qualitative and/or quantitative evolution of GAGs, as supported by Western immunoblotting. Thus, IRSI can simultaneously reveal the location of proteins, PGs, GAGs and sulfated GAGs in HFs in a reagent- and label-free manner. From a dermatological point of view, IRSI shows its potential as a promising technique to study alopecia.

Screening of hair growth promoting activity of Punica granatum L. (pomegranate) leaves extracts and its potential to exhibit antidandruff and anti-lice effect

The intent of the present investigation was to explore the utility of alcoholic and aqueous extract of Punica granatum L. as hair growth promoter along with anti-lice and antidandruff activity. A filter paper diffusion approach was employed for screening of the pediculocidal and ovicidal activity. Albino mice, preselected for their telogen phase of hair growth were used during the study. The prepared extracts, Minoxidil and control were applied over shaved skin surface on to the backs of mice to assess telogen to anagen transition. The qualitative and quantitative analysis was performed. The outcome of the studies revealed that Punica granatum L. alcoholic and aqueous extracts exhibited prominent anti-lice activity. The transition of telogen to anagen phase of the number of anagen hair follicle was observed in approximately 45, 27 and 51% of animals treated with alcoholic and aqueous extract of Punica granatum L., and Minoxidil, respectively, which suggest the hair growth promoting potential of the extract of Punica granatum L. Also, 3 % Punica granatum L. alcoholic extracts exhibited a potent antidandruff activity against fungal strains tested. Maltol, was identified as a principal phytoconstituent in the alcoholic extract. The findings greatly suggest anti-lice, antidandruff and hair growth promoting potential of the extract of Punica granatum L.

Hair Histology and Glycosaminoglycans Distribution Probed by Infrared Spectral Imaging: Focus on Heparan Sulfate Proteoglycan and Glypican-1 during Hair Growth Cycle.

The expression of glypicans in different hair follicle (HF) compartments and their potential roles during hair shaft growth are still poorly understood. Heparan sulfate proteoglycan (HSPG) distribution in HFs is classically investigated by conventional histology, biochemical analysis, and immunohistochemistry. In this report, a novel approach is proposed to assess hair histology and HSPG distribution changes in HFs at different phases of the hair growth cycle using infrared spectral imaging (IRSI). The distribution of HSPGs in HFs was probed by IRSI using the absorption region relevant to sulfation as a spectral marker. The findings were supported by Western immunoblotting and immunohistochemistry assays focusing on the glypican-1 expression and distribution in HFs. This study demonstrates the capacity of IRSI to identify the different HF tissue structures and to highlight protein, proteoglycan (PG), glycosaminoglycan (GAG), and sulfated GAG distribution in these structures. The comparison between anagen, catagen, and telogen phases shows the qualitative and/or quantitative evolution of GAGs as supported by Western immunoblotting. Thus, IRSI can simultaneously reveal the location of proteins, PGs, GAGs, and sulfated GAGs in HFs in a reagent- and label-free manner. From a dermatological point of view, IRSI shows its potential as a promising technique to study alopecia.

Identification of potential key genes and pathways associated with the Pashmina fiber initiation using RNA-Seq and integrated bioinformatics analysis

Pashmina goat (Capra hircus) is an economically important livestock species, which habitats the cold arid desert of the Ladakh region (India), and produces a princely animal fiber called Pashmina. The Pashmina goat has a double coat fleece as an adaptation to the very harsh cold winters the outer long coarse hair (guard hair) produced from primary hair follicles and the inner fine Pashmina fiber produced from secondary hair follicles. Pashmina fiber undergoes a circannual and synchronized growth cycle. In the present study, we analyzed transcriptome profiles from 10 different Pashmina goats during anagen and telogen to delineate genes and signaling pathways regulating active (anagen) and regressive (telogen) phases of the follicle growth. During anagen, 150 genes were expressed at significantly higher levels with log (FC) > 2 and padj < 0.05. The RNA seq results were subjected to qRT-PCR validation. Among the nine genes selected, the expression of HAS1, TRIB2, P2RX1. PRG4, CNR2, and MMP25 were significantly higher (p < 0.05) in the anagen phase, whereas MC4R, GIPC2, and CDO1 were significantly expressed (p < 0.05) in the telogen phase which supports and validates the gene expression pattern from the RNA-sequencing. Differentially expressed genes revealed that Pashmina fiber initiation is largely controlled by signaling pathways like Wnt, NF-Kappa, JAK-STAT, Hippo, MAPK, Calcium, and PI3K-Akt. Expression of genes from the Integrin family, Cell adhesion molecules, and ECM-receptors were observed to be at much higher levels during anagen. We identified key genes (IL36RN, IGF2, ITGAV, ITGA5, ITCCR7, CXCL5, C3, CCL19, and CXCR3) and a collagen cluster which might be tightly correlated with anagen-induction. The regulatory network suggests the potential role of RUNX3, NR2F1/2, and GATA family transcription factors in anagen-initiation and maintaining fiber quality in Pashmina goats.

DNA methylation and histone acetylation are involved in Wnt10b expression during the secondary hair follicle cycle in Angora rabbits.

Secondary hair follicles (SHFs) in the Angora rabbit exhibit classic cyclic hair development, but the multiple molecular signals involved in hair cycling are yet to be explored in detail. In the present study, we investigated the expression pattern, methylation and histone H3 acetylation status of Wnt10b, as a molecular signal participating in hair cycling, during the SHF cycle in the Angora rabbit. Expression of Wnt10b at the anagen phase was significantly higher than that at both the telogen and catagen phases, suggesting that Wnt10b might serve as a critical activator during cyclic transition of SHFs. Methylation frequency of the fifth CpG site (CpG5-175bp) in CpG islands at the anagen phase was lower than that at both the catagen and telogen phases. The methylation status of the CpG5 site was negatively correlated with Wnt10b expression. This indicated that the methylation of CpG5 might participate in Wnt10b transcriptional suppression in SHFs. Furthermore, histone H3 acetylation status in the regions-256~-11bp and 98~361bp were significantly lower at both the catagen and telogen phases than at the anagen phase. The histone H3 acetylation level was significantly positively correlated with Wnt10b expression. This confirmed that histone acetylation was likely involved in upregulating Wnt10b transcription in SHFs. Additionally, potential binding to the transcription factors ZF57 and HDBP was predicted within the CpG5 site. In conclusion, our findings reveal the epigenetic mechanism of Wnt10b transcription and provide a new insight into epigenetic regulation during the SHF cycle in the Angora rabbit.

The PD-1/PD-L1 pathway in murine hair cycle transition: a potential anagen phase regulator.

Programmed cell death protein-1 (PD-1) is primarily recognized as an inhibitory receptor involved in the regulation of immunological tolerance. However, recent studies have indicated that PD-1/PD-L1 signaling could also regulate the functions of nonimmune cells and may be involved in regulating hair biology. In this study, we showed in a mouse model of depilation-induced hair cycling that PD-1/PD-L1 are expressed in the murine epidermis and hair follicle (HF) in a hair cycle-dependent manner. During HF morphogenesis, PD-1 expression was strongly decreased during the anagen phase compared with the catagen and telogen phases. PD-L1 expression was enhanced during the catagen phase compared with the anagen and telogen phases. Moreover, direct blockade of PD-L1 not only accelerated hair anagen phase onset but also delayed catagen progression. In conclusion, our findings indicated that PD-1/PD-L1 signaling may act as a negative regulator of hair cycle transition. Anti-PD-1/PD-L1 therapy may thus be a promising strategy for treating anagen-reduced hair loss.