Biology of the Hair Follicle: The Basics
March 2006
in “Seminars in Cutaneous Medicine and Surgery”
TLDR The document concludes that understanding hair follicle biology can lead to better hair loss treatments.
The document from 2006 explores the intricate biology of the hair follicle and its role in hair growth cycles, which consist of anagen, catagen, and telogen phases. It highlights the importance of stem cells in the regenerative nature of hair follicles and the influence of various signaling molecules on the hair growth cycles. The paper emphasizes the need to understand these molecular mechanisms to develop effective treatments for hair loss and unwanted hair growth, conditions that affect a significant portion of adults. It also discusses the hair follicle's utility as a model for studying other biological processes and the psychosocial impact of hair loss. Additionally, the document delves into the specifics of hair follicle cycling, the role of the hairless gene in catagen, and the influence of growth factors, hormones, and stress on hair growth. It particularly focuses on androgenetic alopecia, the process of hair follicle miniaturization, and the role of DHT, 5a-reductase, and androgen receptors in this condition. The document suggests that a better understanding of stem cell signals and the intrinsic hair cycle clock could lead to improved treatments for hair loss disorders.
View this study on scmsjournal.com →
Cited in this study
research A role of melatonin in neuroectodermal‐mesodermal interactions: the hair follicle synthesizes melatonin and expresses functional melatonin receptors
Hair follicles produce and respond to melatonin, affecting hair growth and sensitivity to estrogen.
research Premature termination of hair follicle morphogenesis and accelerated hair follicle cycling in Iasi congenital atrichia (fzica) mice points to fuzzy as a key element of hair cycle control
The fuzzy gene is crucial for controlling hair growth cycles.
research Towards Dissecting the Pathogenesis of Retinoid-Induced Hair Loss: All-Trans Retinoic Acid Induces Premature Hair Follicle Regression (Catagen) by Upregulation of Transforming Growth Factor-β2 in the Dermal Papilla
All-trans retinoic acid causes hair loss by increasing TGF-β2 in hair follicle cells.
research Control of Human Hair Growth by Neurotrophins: Brain-Derived Neurotrophic Factor Inhibits Hair Shaft Elongation, Induces Catagen, and Stimulates Follicular Transforming Growth Factor β2 Expression
Brain-Derived Neurotrophic Factor (BDNF) slows down hair growth and promotes hair follicle regression.
research A Hot New Twist to Hair Biology
Capsaicin, found in chili peppers, can slow down hair growth by affecting skin cells and hair follicles.
research Mast cell deficient and neurokinin-1 receptor knockout mice are protected from stress-induced hair growth inhibition
Certain mice without specific receptors or mast cells don't lose hair from stress.
research Molecular principles of hair follicle induction and morphogenesis
Hair follicle development is controlled by interactions between skin tissues and specific molecular signals.
research BMP signaling in the control of skin development and hair follicle growth
BMP signaling is crucial for skin and hair growth.
research Rooster feathering, androgenic alopecia, and hormone-dependent tumor growth: What is in common?
Sex hormones affect hair and feather growth and may help manage alopecia and hormone-dependent cancers.
research Burden of Hair Loss: Stress and the Underestimated Psychosocial Impact of Telogen Effluvium and Androgenetic Alopecia
Hair loss causes stress and affects mental health; treatment and support needed.
research Neurogenic Inflammation in Stress-Induced Termination of Murine Hair Growth Is Promoted by Nerve Growth Factor
Stress increases a factor in mice that leads to hair loss, and blocking this factor may prevent it.
research Estrogens and the hair follicle. Ostrogene und der Haarfollikel
Estrogens generally inhibit hair growth and improve skin quality, but their exact effects on hair follicles are complex and not fully understood.
research Hair cycle and hair pigmentation: dynamic interactions and changes associated with aging
As people age, their hair follicles produce less pigment, leading to gray and white hair, due to factors like reduced enzyme activity and damage to melanocyte DNA.
research Epithelial growth control by neurotrophins: leads and lessons from the hair follicle
Neurotrophins are important for hair growth and could help treat hair loss.
research Identification of Androgen-Inducible TGF-β1 Derived from Dermal Papilla Cells as a Key Mediator in Androgenetic Alopecia
TGF-β1 from dermal papilla cells suppresses hair growth, and targeting it may help treat androgenetic alopecia.
research Androgenetic Alopecia in Women
Androgenetic alopecia in women needs more research and better management strategies.
research Prolactin and Its Receptor Are Expressed in Murine Hair Follicle Epithelium, Show Hair Cycle-Dependent Expression, and Induce Catagen
Prolactin affects hair growth cycles and can cause early hair follicle regression.
research Stress Inhibits Hair Growth in Mice by Induction of Premature Catagen Development and Deleterious Perifollicular Inflammatory Events via Neuropeptide Substance P-Dependent Pathways
Stress stops hair growth in mice by causing early hair growth phase end and harmful inflammation through a specific nerve-related pathway.
research Exogen, Shedding Phase of the Hair Growth Cycle: Characterization of a Mouse Model
Researchers found that hair shedding happens mostly when new hair is growing and involves a unique process.
research An Investigation of Apoptosis in Androgenetic Alopecia
Apoptosis contributes to hair loss in androgenetic alopecia.
research Mutant laboratory mice with abnormalities in hair follicle morphogenesis, cycling, and/or structure: annotated tables
Mutant mice help researchers understand hair growth and related genetic factors.
research Indications for a brain‐hair follicle axis: inhibition of keratinocyte proliferation and up‐regulation of keratinocyte apoptosis in telogen hair follicles by stress and substance P
Stress can cause hair loss by negatively affecting hair follicles and this effect might be reversed with specific treatments.
research Possible mechanisms of miniaturization during androgenetic alopecia or pattern hair loss
Hair loss occurs due to fewer papillary cells, smaller follicles, and shorter growth phases.
research Effects of 17-β-Estradiol and ICI 182 780 on Hair Growth in Various Strains of Mice
17-β-Estradiol applied to the skin stops hair growth, while ICI 182 780 helps hair grow in mice.
research Induction of the hair growth phase in postnatal mice by localized transient expression of Sonic hedgehog
Activating the Sonic hedgehog gene in mice can start the hair growth phase.
research The Biology of Hair Follicles
Hair follicle biology advancements may lead to better hair growth disorder treatments.
research What controls hair follicle cycling?
The control system for hair growth cycles is not well understood and needs more research.
research WNT Signaling in the Control of Hair Growth and Structure
The research shows that a gene called Wnt3 affects hair growth and structure, causing short hair and balding when overactive.
research DERMAL-EPIDERMAL INTERACTIONS
Hair loss is mainly caused by hormones, autoimmune issues, and chemotherapy, and needs more research for treatments.
research Androgen Induction of Follicular Epithelial Cell Growth Is Mediated via Insulin-like Growth Factor-I from Dermal Papilla Cells
Male hormones promote hair cell growth by using a growth factor from nearby skin cells.
research The hair cycle and its regulation
Hormones, nutrition, and seasonal changes regulate hair growth cycles, with androgens extending growth phases and factors like aging and malnutrition affecting hair loss and thinning.
research Growth of the Hair
Hair growth is cyclic and influenced mainly by local factors.
Related
research Morphogenesis, Growth Cycle, and Molecular Regulation of Hair Follicles
Hair growth and health are influenced by factors like age, environment, and nutrition, and are controlled by various molecular pathways. Red light can promote hair growth, and understanding these processes can help treat hair-related diseases.