scholarly journals Localisation and regulation of cholesterol transporters in the human hair follicle: mapping changes across the hair cycle

2021 ◽  
Author(s):  
Megan A. Palmer ◽  
Eleanor Smart ◽  
Iain S. Haslam
Keyword(s):  
Hair Follicle ◽  
Human Hair ◽  
Vital Role ◽  
Transport Proteins ◽  
Hair Follicles ◽  
Regulatory Control ◽  
Cholesterol Transport ◽  
Hair Cycle ◽  
Human Hair Follicle

AbstractCholesterol has long been suspected of influencing hair biology, with dysregulated homeostasis implicated in several disorders of hair growth and cycling. Cholesterol transport proteins play a vital role in the control of cellular cholesterol levels and compartmentalisation. This research aimed to determine the cellular localisation, transport capability and regulatory control of cholesterol transport proteins across the hair cycle. Immunofluorescence microscopy in human hair follicle sections revealed differential expression of ATP-binding cassette (ABC) transporters across the hair cycle. Cholesterol transporter expression (ABCA1, ABCG1, ABCA5 and SCARB1) reduced as hair follicles transitioned from growth to regression. Staining for free cholesterol (filipin) revealed prominent cholesterol striations within the basement membrane of the hair bulb. Liver X receptor agonism demonstrated active regulation of ABCA1 and ABCG1, but not ABCA5 or SCARB1 in human hair follicles and primary keratinocytes. These results demonstrate the capacity of human hair follicles for cholesterol transport and trafficking. Future studies examining the role of cholesterol transport across the hair cycle may shed light on the role of lipid homeostasis in human hair disorders.

A method for culturing human hair follicle cells. (II). Plucked human hair follicles.

1988 ◽  
Vol 50 (2) ◽  
pp. 271-276 ◽  
Author(s):  
Ryuichiro KUWANA ◽  
Seiji ARASE ◽  
Yasushi SADAMOTO ◽  
Hideki NAKANISHI ◽  
Katsuyuki TAKEDA
Keyword(s):  
Hair Follicle ◽  
Human Hair ◽  
Hair Follicles ◽  
Follicle Cells ◽  
Human Hair Follicle

The effect of IGF-I on the growth of secondary hair follicles of the Cashmere goat in vitro

1997 ◽  
Vol 1997 ◽  
pp. 170-170
Author(s):  
H. Galbraith ◽  
D. Sims ◽  
D. Hazlerigg
Keyword(s):  
Growth Factors ◽  
Hair Follicle ◽  
Human Hair ◽  
Hair Follicles ◽  
Cashmere Goat ◽  
Igf I ◽  
Hair Follicle Cycle ◽  
Insulin Like Growth Factors

Factors regulating the growth of Cashmere fibre and the hair follicle cycle are poorly understood. Insulin-like growth factors (IGFs) or insulin at higher concentrations, have been shown to stimulate in vitro growth of human hair follicles (Philpott et al, 1994). The role of such mitogens in the production of cashmere fibre by the Cashmere goat has not been previously investigated. The objective the study reported here was to investigate the growth of hair follicles in the absence and presence of insulin or IGF-I using our established in vitro technique.

Effects of Finasteride on Apoptosis and Regulation of the Human Hair Cycle

2002 ◽  
Vol 6 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Marty E. Sawaya ◽  
Ulrike Blume-Peytavi ◽  
Diane L. Mullins ◽  
Bernard P. Nusbaum ◽  
David Whiting ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Human Hair ◽  
Time Course ◽  
Central Element ◽  
Constitutive Expression ◽  
Hair Follicles ◽  
Dermal Fibroblasts ◽  
Follicle Cells ◽  
Hair Cycle ◽  
Cellular Expression

Background: A number of studies have provided evidence that apoptosis is a central element in the regulation of hair follicle regression. In androgenetic alopecia (AGA), the exact location and control of key players in the apoptotic pathways remains obscure. Objective: In the present study, we used a panel of antibodies and investigated the spatial and cellular pattern of expression of caspases and inhibitors of apoptosis (IAPs), such as XIAP and FLIP, in men with normal scalp and in men with AGA before and after 6 months of treatment with 1 mg oral finasteride treatment. Methods and Results: Constitutive expression of caspases-1, −3, −8, and −9 and XIAP was detected predominantly within the isthmic and infundibular hair follicle area, basilar layer of the epidermis, and eccrine and sebaceous glands. AGA-affected tissues showed an increase in caspase (−1, −3, −6, −9) immunoreactivity with a concomitant decrease in XIAP staining. After 6 months of finasteride treatment, both caspases and XIAP were similar to levels exhibited by normal subjects. Immunoblot analysis was performed to determine antibody specificity and cellular expression of caspases. Purified populations of keratinocytes, melanocytes, dermal papilla, and dermal fibroblasts derived from human hair follicles were cultured in vitro and treated with 0.5 μm staurosporin. Time-course experiments revealed that processing of caspase-3 is a principal event during apoptosis of these hair cell types. Conclusion: These data suggest that alterations in levels of caspases and IAPs regulate hair follicle homeostasis. Moreover, finasteride appears to influence caspase and XIAP expression in hair follicle cells thus signaling anagen, active growth in the hair cycle.

scholarly journals DEMONSTRATION OF THE HUMAN HAIR FOLLICLE MAGNETORECEPTION OF BIOMAGNETISM RADIATED BY THE CONCAVE PART OF THE HUMAN HAND

2020 ◽  
Vol 8 (5) ◽  
pp. 348-354
Author(s):  
Abraham A. Embi
Keyword(s):  
Optical Microscopy ◽  
Hair Follicle ◽  
Human Hair ◽  
Quantum Interference ◽  
Hair Follicles ◽  
The Body ◽  
Human Hand ◽  
Human Hair Follicle ◽  
Concave Part ◽  
Microscopy Method

Biological material has been documented to produce an external magnetic field that radiates out. There have been several papers documenting the magnetic fields produced by steady currents in the body. The most notable was published in 1980 by Cohen et al. where the human hair follicle was used as sentinel and biophysically evaluated via sophisticated equipment such as a double planar Superconducting Quantum Interference Devices (SQUID). Most recently, in 2019 Cohen’s work was duplicated by Khan,S by also using double-planar gladiometers. Of interest to this manuscript is that since the introduction of anovel optical microscopy method in 2016 by Scherlag BJ et al is that numerous papers have been introduced in the literature now identifying intrinsic biomagnetic properties of the follicle such as penetration through glass barriers. In this manuscript, a concept of biomagnetic fields by the concave part of the human hand transferring energy to hair follicles is introduced, this was accomplished by using a novel optical microscopy method, in other words, the hair follicle is not limited to radiate out biomagnetism; but also, to receive externally radiated biomagnetic fields from a body part. This magneto receptive property is herein introduced.

scholarly journals Stress-sensing in the human greying hair follicle: Ataxia Telangiectasia Mutated (ATM) depletion in hair bulb melanocytes in canities-prone scalp

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Stephen K. Sikkink ◽  
Solene Mine ◽  
Olga Freis ◽  
Louis Danoux ◽  
Desmond J. Tobin
Keyword(s):  
Oxidative Stress ◽  
Hair Follicle ◽  
Ataxia Telangiectasia ◽  
Human Hair ◽  
Scalp Hair ◽  
Ataxia Telangiectasia Mutated ◽  
Human Hair Follicle ◽  
Anagen Hair ◽  
Stress Sensing

Abstract Canities (or hair greying) is an age-linked loss of the natural pigment called melanin from hair. While the specific cause(s) underlying the loss of melanogenically-active melanocytes from the anagen hair bulbs of affected human scalp remains unclear, oxidative stress sensing appears to be a key factor involved. In this study, we examined the follicular melanin unit in variably pigmented follicles from the aging human scalp of healthy individuals (22–70 years). Over 20 markers were selected within the following categories: melanocyte-specific, apoptosis, cell cycle, DNA repair/damage, senescence and oxidative stress. As expected, a reduction in melanocyte-specific markers in proportion to the extent of canities was observed. A major finding of our study was the intense and highly specific nuclear expression of Ataxia Telangiectasia Mutated (ATM) protein within melanocytes in anagen hair follicle bulbs. ATM is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks and functions as an important sensor of reactive oxygen species (ROS) in human cells. The incidence and expression level of ATM correlated with pigmentary status in canities-affected hair follicles. Moreover, increased staining of the redox-associated markers 8-OHdG, GADD45 and GP-1 were also detected within isolated bulbar melanocytes, although this change was not clearly associated with donor age or canities extent. Surprisingly, we were unable to detect any specific change in the expression of other markers of oxidative stress, senescence or DNA damage/repair in the canities-affected melanocytes compared to surrounding bulbar keratinocytes. By contrast, several markers showed distinct expression of markers for oxidative stress and apoptosis/differentiation in the inner root sheath (IRS) as well as other parts of the hair follicle. Using our in vitro model of primary human scalp hair follicle melanocytes, we showed that ATM expression increased after incubation with the pro-oxidant hydrogen peroxide (H2O2). In addition, this ATM increase was prevented by pre-incubation of cells with antioxidants. The relationship between ATM and redox stress sensing was further evidenced as we observed that the inhibition of ATM expression by chemical inhibition promoted the loss of melanocyte viability induced by oxidative stress. Taken together these new findings illustrate the key role of ATM in the protection of human hair follicle melanocytes from oxidative stress/damage within the human scalp hair bulb. In conclusion, these results highlight the remarkable complexity and role of redox sensing in the status of human hair follicle growth, differentiation and pigmentation.

scholarly journals Sustained Human Hair Follicle Growth Ex Vivo in a Glycosaminoglycan Hydrogel Matrix

2019 ◽  
Vol 20 (7) ◽  
pp. 1741 ◽  
Author(s):  
Sandra Fernández-Martos ◽  
María Calvo-Sánchez ◽  
Karla García-Alonso ◽  
Begoña Castro ◽  
Bita Hashtroody ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Human Hair ◽  
Wound Repair ◽  
Ex Vivo ◽  
Hair Follicles ◽  
Stem Cell Markers ◽  
Follicle Growth ◽  
Human Hair Follicle ◽  
Hydrogel Matrix ◽  
Hair Follicle Growth

Glycosaminoglycans (GAGs) and associated proteoglycans have important functions in homeostatic maintenance and regenerative processes (e.g., wound repair) of the skin. However, little is known about the role of these molecules in the regulation of the hair follicle cycle. Here we report that growing human hair follicles ex vivo in a defined GAG hydrogel mimicking the dermal matrix strongly promotes sustained cell survival and maintenance of a highly proliferative phenotype in the hair bulb and suprabulbar regions. This significant effect is associated with the activation of WNT/β-catenin signaling targets (CCDN1, AXIN2) and with the expression of stem cell markers (CK15, CD34) and growth factors implicated in the telogen/anagen transition (TGFβ2, FGF10). As a whole, these results point to the dermal GAG matrix as an important component in the regulation of the human hair follicle growth cycle, and to GAG-based hydrogels as potentially relevant modulators of this process both in vitro and in vivo.

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