Hyperinnervation Inhibits Organ-Level Regeneration In Mammalian Skin

This study found that acute stress can cause rapid hair loss by triggering necrosis in hair follicle cells and initiating autoimmunity, revealing a mechanism where stress-induced nerve activity leads to tissue damage and immune system activation.

In this study, activating TRPV1 nociceptors in mice skin stimulated dormant hair follicles and promoted hair growth through a mechanism involving dermal macrophages, fibroblasts, and neuropeptides, highlighting a new role for nociceptors in tissue recovery after injury.

In this study, researchers found that hair follicle stem cells activate an immune-modulatory program during wound healing, promoting Treg cell expansion and aiding skin repair, while deleting certain immune components impaired healing and increased inflammation in a mouse model.

This study found that CXCL12+ fibroblast subsets in mouse skin play a critical role in recruiting neutrophils and defending against S. aureus infection, with similar fibroblast activity observed in human psoriatic skin.

In this study, researchers demonstrated that human hair follicle outer root sheath cells release ATP, serotonin, and histamine in response to mechanical stimulation, which subsequently activates surrounding sensory neurons.

In this study, researchers observed that mechanosensory neurons initially develop similar morphologies across different skin regions but diverge post-natally, adapting to the type of skin they innervate, with bone morphogenetic protein signaling crucial for forming Meissner corpuscles in glabrous skin.

This review examines diverse regenerative strategies in animals and highlights how biochemical, immunological, and mechanical signals can work together for successful skin regeneration in adult mammals, but it reports no new experimental results.

This review discusses the roles of peripheral nerves in stem cell and immune responses within the skin and hematopoietic system, emphasizing their potential in developing new therapies; it reports no new experimental results.

This review discusses the interactions and signals affecting skin stem cells and their environments but reports no new experimental results; the authors highlight the need for understanding these processes to enhance tissue rejuvenation and repair.

This review discusses the role of hair follicle stem cells as active signaling centers in skin homeostasis, highlighting recent advancements and reporting no new clinical results.

This study found that sympathetic nerves and arrector pili muscles form a niche that modulates hair follicle stem cell activity, revealing their role in hair follicle regeneration.

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

This study found that lymphatic vessels in mice are important for hair follicle development and organization, as their depletion blocks hair growth.

This study found that activating the Sonic hedgehog pathway in scarring wounds can remodel the dermis to promote hair follicle regeneration, highlighting a potential new approach to enhance healing.

This study found that, in mouse tail epidermis, stem cells rapidly activate and regenerate new progenitors to repair wounds, with mechanisms affecting their proliferation, differentiation, and migration.

This study found that hair follicles in mice and humans can convert wound-related myofibroblasts into adipocytes, suggesting a potential pathway to reduce scar formation by activating BMP signaling.

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.

The researchers reported that dsRNA from damaged skin activates TLR3, promoting hair follicle regeneration, while TLR3-deficient animals fail to initiate this process, suggesting potential therapeutic approaches for hair neogenesis.

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 Merkel cell clusters require Frizzled6 signaling for their polarity information, while other hair follicle-associated structures align their orientation based on the hair follicle itself.

This study reports the first instance of skin autotomy in mammals, specifically in African spiny mice, and suggests they may possess a greater regenerative capacity than previously understood, possibly offering insights for regenerative medicine.

This study found that distinct low-threshold mechanoreceptors innervate different hair follicle types in mice, suggesting that these follicles serve as unique mechanosensory structures in touch perception.

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.

Hair follicles can regrow in wounded adult mouse skin using a process like embryo development.

This study successfully developed a reproducible mouse model demonstrating fetal scarless wound healing, which may provide insights for minimizing scarring in adults.

In this study, fetal rat wounds at gestational age 16 days healed without scar formation and resembled normal skin architecture, unlike those at 18 days which resulted in scarring and lack of hair follicles.