Cell Types Promoting Goosebumps Form a Niche to Regulate Hair Follicle Stem Cells

This study explored the complex roles of niche cells in regulating hair follicle stem cells, identifying specific cell functions such as signaling, sensing, and relaying messages, which could provide insights into treating hair loss conditions like androgenetic alopecia and alopecia areata.

Stress can cause hair to turn gray by depleting stem cells.

This study found that light stimulation of intrinsically photosensitive retinal ganglion cells in the eyes can activate hair follicle stem cells through a neural circuit involving the sympathetic nervous system.

This review discusses the emerging roles of transit-amplifying cells in tissue regeneration and cancer formation, highlighting their significance beyond a mere transitional state in hair follicles and the hematopoietic system.

This study found that PDGFA is critical for the proliferation and maintenance of adipocyte stem cells in skin but not other white adipose tissues, highlighting unique regulatory mechanisms in different tissue depots.

This study found that Sonic Hedgehog secreted by hair follicle transit-amplifying cells is essential for dermal adipogenesis and hair follicle growth by acting on adipocyte precursors.

This review discusses the role of Foxc1 and type XVII collagen in hair follicle stem cell quiescence and aging, identifying mechanisms that relate to hair thinning and hair loss, and reports no new results.

This study found that chemical sympathectomy inhibited hair follicle growth in mice, suggesting that sympathetic nerves may regulate keratinocyte behavior to promote hair growth.

This study characterizes gene expression patterns in embryonic hair follicle progenitors and their niche, identifying signaling pathways like axon guidance that may drive cellular rearrangements for hair follicle formation.

This study found that red light accelerated the transition from the resting to growth phase in hair follicles faster than green and blue light in mice, suggesting it may stimulate hair growth.

This narrative review examines the interactions between skin stem cells and their niches, finding new insights from advancements in genetic and imaging tools but reporting no new experimental results.

This study found that in androgenic alopecia, the arrector pili muscle degenerates and is replaced by fat, unlike in normal skin or telogen effluvium.

This study concluded that terminal Schwann cells are essential for the maintenance and regeneration of mechanosensory lanceolate complexes at hair follicles in adult mice.

This study found that skin fibroblasts in mice arise from two distinct lineages which contribute differently to dermal structure and repair, impacting hair follicle formation during wound healing.

This study found that loss of contact between the arrector pili muscle and the hair follicle bulge may explain why hair loss in male and female pattern baldness is largely irreversible, unlike in alopecia areata.

This study found that dermal Shh signaling regulates specific dermal papilla signatures essential for maintaining hair follicle development, suggesting that the Shh-Noggin signaling loop is crucial for hair morphogenesis.

FGF18 helps keep hair in its resting phase, affecting hair growth cycles.

This study found that polycomb-group-mediated repression plays a key role in regulating hair follicle stem cell states and lineage progression by distinct mechanisms in adult mouse skin.

This study found that Shh from neurons signals to Gli1-expressing cells in the hair follicle, cultivating a niche where these bulge cells can potentially transform into epidermal stem cells in wound healing.

Nephronectin helps attach muscle cells to hair follicles.

This review introduces the morphological and molecular principles of hair follicle development but reports no new experimental results, focusing on recent insights and forming a working hypothesis.

This study demonstrated that multipotent stem cells in adult mice whisker follicles migrate to produce whisker growth, and that this process requires precise control of stem cell trafficking.

This study found that subcutaneous injections of guanethidine or 6-hydroxydopamine induced premature hair growth in mice, suggesting a role for sympathetic nerves in hair growth control.

This study found that treating neonatal mice with the neurotoxin 6-OHDA resulted in temporary hair loss and thinner skin compared to control mice, linking sympathetic neurons to hair growth and skin thickness.