22 citations
,
July 2019 in “PLOS ONE” This study found that lymphatic vessels promote hair follicle growth in mice and may represent new therapeutic targets for hair loss conditions.
21 citations
,
April 2019 in “Journal of cutaneous pathology” This study found a significant reduction in Treg cell frequency in alopecia areata compared to other autoimmune and non-autoimmune skin diseases using immunohistochemical staining.
163 citations
,
April 2019 in “Nature Communications” This study found that mechanical skin stretching can stimulate hair stem cell proliferation and hair regeneration by activating a complex pathway involving WNT, BMP-2, and M2 macrophages.
5 citations
,
April 2019 in “Plastic and reconstructive surgery. Global open” This literature review suggests that fractional laser therapies may positively impact hair regrowth in androgenic alopecia, though current evidence is mostly limited to small studies and case reports, highlighting a need for more comprehensive randomized controlled trials to confirm their efficacy and safety.
101 citations
,
March 2019 in “Cell Stem Cell” This study found that Oncostatin M, via JAK-STAT5 signaling, keeps hair follicle stem cells inactive, and its removal leads to hair growth initiation in mice.
21 citations
,
March 2019 in “Experimental Dermatology” This review discusses the role of perifollicular macrophages in hair growth and suggests targeting them could be relevant for managing hair growth disorders, but reports no new results.
39 citations
,
March 2019 in “Dermatologic Surgery” This study's meta-analysis reported that PRP injections significantly increased hair density compared to baseline and placebo in androgenetic alopecia patients, supporting its use as a beneficial treatment.
21 citations
,
January 2019 in “Lasers in Medical Science” This review found that low-level laser therapy significantly increased hair density in adults with androgenic alopecia compared to sham treatments, with greater effects observed at lower treatment frequencies.
5 citations
,
November 2018 in “Skin appendage disorders” This study found that oral finasteride increased the total number of hairs in men with androgenetic alopecia by 55% over 2.5 years, but did not reduce the number of miniaturized vellus hairs.
30 citations
,
May 2018 in “Experimental Dermatology” This article reviews the cellular dynamics affecting dermal papilla size in androgenetic alopecia and suggests targeting DP size could improve therapies, but it presents no new clinical data.
27 citations
,
May 2018 in “Journal of Dermatological Science” This study suggests that M2 macrophages play a key role in promoting wound-induced hair neogenesis in mice by producing growth factors like Igf1 and Fgf2.
27 citations
,
April 2018 in “Journal of autoimmunity” In this study, iNKT10 cells were found to play a significant role in preventing and treating alopecia areata in a humanized mouse model, suggesting these cells could have potential in managing related autoimmune disorders.
15 citations
,
February 2018 in “Journal of Cosmetic and Laser Therapy” This study observed hair regrowth and increased density in four cases of androgenetic alopecia treated with a non-ablative erbium glass fractional laser and topical finasteride, with no significant side effects reported.
9 citations
,
December 2017 in “The Journal of Allergy and Clinical Immunology” This review discusses the evolution of alopecia areata treatments towards more targeted therapies and reports no new clinical results, emphasizing cooperation between clinicians and scientists in understanding the disease's pathophysiology.
102 citations
,
December 2017 in “The journal of investigative dermatology. Symposium proceedings/The Journal of investigative dermatology symposium proceedings” This review discusses the role of immune privilege collapse in the pathogenesis of alopecia areata, emphasizing the potential for therapeutic manipulation of hair bulb immune privilege to offer new treatment options, and reports no new results.
11 citations
,
October 2017 in “Journal of Investigative Dermatology” This study found that topical application of mitochondrial electron transport chain inhibitors stimulated hair follicle stem cell activation and hair regrowth in aged mice by promoting lactate production.
202 citations
,
August 2017 in “Nature cell biology” This study found that glycolytic metabolism and lactate production are crucial for hair follicle stem cell activation, and manipulating these processes can stimulate the hair cycle.
26 citations
,
May 2017 in “Lasers in Medical Science” This study found that combining ablative fractional CO₂ laser therapy with hair growth factors significantly increased hair density in men with androgenetic alopecia compared to using growth factors alone.
117 citations
,
March 2017 in “Nature Communications” This study shows that macrophage-induced TNF signaling can activate hair follicle stem cells and promote new hair follicle formation after wounding by regulating AKT/β-catenin pathways.
9 citations
,
January 2017 in “International Journal of Trichology” This study suggests that mast cells may play a role in stress-related hair loss associated with telogen effluvium.
25 citations
,
July 2016 in “The journal of investigative dermatology/Journal of investigative dermatology” This study found that applying topical imiquimod during mid and late telogen in mice activates hair follicle stem cells and influences immune cell infiltration, promoting hair cycle entry independently of Wnt signaling.
159 citations
,
October 2015 in “Science Advances” This study observed that applying JAK-STAT pathway inhibitors to mouse and human skin led to rapid hair growth by inducing the anagen phase of hair follicles.
214 citations
,
September 2015 in “Stem Cells Translational Medicine” This study found that platelet-rich plasma injections significantly increased hair count and density in patients with male pattern hair loss without major side effects, suggesting it may be a safe and effective treatment option.
212 citations
,
September 2015 in “Journal of Investigative Dermatology” This article presents a comprehensive guide for classifying human hair follicle cycle stages in vivo using scalp xenografts on immunocompromised mice, offering valuable resources for researchers in the field.
26 citations
,
May 2015 in “Lasers in Surgery and Medicine” This study concluded that ablative fractional lasers may induce hair regrowth in mice by activating the Wnt/β-catenin pathway.
236 citations
,
April 2015 in “Cell” This study found that patterned hair plucking in mice triggers a collective regeneration response in nearby unplucked hair follicles via a quorum sensing mechanism involving immune signaling.
46 citations
,
March 2015 in “Regeneration” This review revisits the mechanisms of wound induced hair follicle neogenesis in mice and concludes that the process involves canonical WNT signaling activated by Fgf9 from γδ T cells, but more research is needed to fully understand its cellular bases.
16 citations
,
March 2015 in “Clinical and experimental dermatology” This study found that mycophenolic acid promotes dermal papilla cell proliferation and anagen hair follicle induction in mice, suggesting potential as a treatment for hair-loss disorders.
7 citations
,
January 2015 in “Journal of the European Academy of Dermatology and Venereology” This letter to the editor on postpartum telogen effluvium does not include new research findings or data.
175 citations
,
December 2014 in “PLoS Biology” This study found that macrophages near hair follicles contribute to the activation of skin epithelial stem cells in mice, suggesting a novel role for macrophages in regulating hair growth.
30 citations
,
October 2014 in “Experimental Dermatology” This study found that leptin from dermal white adipose tissue may regulate hair growth and cycle progression through its receptor on hair follicle epithelium in mice and humans.
701 citations
,
August 2014 in “Nature medicine” This study found that JAK inhibitors promote hair regrowth in both mice and human alopecia areata cases by blocking key immune pathways involved in disease development.
426 citations
,
August 2014 in “Nature Medicine” 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.
136 citations
,
July 2014 in “Proceedings of the National Academy of Sciences of the United States of America” This study identified mutations in the FGF5 gene as a cause of extreme eyelash growth in Pakistani families, highlighting a potential target for regulating eyelash growth.
40 citations
,
April 2014 in “Genes & Development” The researchers reported that in mice, prolactin signaling in the skin epithelium inhibits hair follicle stem cell activation, promoting quiescence during periods of high serum prolactin like pregnancy and lactation.
135 citations
,
December 2013 in “Seminars in Cell & Developmental Biology” This review examines the literature on the molecular and cellular makeup of the hair follicle niche and how it influences stem cell behavior during hair regeneration, but does not provide new experimental results.
25 citations
,
December 2013 in “Journal of Investigative Dermatology Symposium Proceedings” In this study, researchers developed a new humanized mouse model for alopecia areata that highlights the role of specific immune cells and may aid in discovering new treatments for the disease.
6 citations
,
August 2013 in “Joint Bone Spine” Tocilizumab treatment was associated with significant hair regrowth in one patient and temporary hair loss followed by regrowth in another.
237 citations
,
June 2013 in “Nature Medicine” This study found that fibroblast growth factor 9, initially secreted by γδ T cells, plays a key role in modulating hair follicle regeneration in mice after skin wounds.
24 citations
,
April 2013 in “PLOS ONE” This study identifies substance P, TNFα, and IFNγ as novel regulators of prolactin and its receptor expression in human skin, suggesting intracutaneous prolactin is not controlled by dopamine.
211 citations
,
April 2013 in “Development” In this study, researchers found that the number of dermal papilla cells in hair follicles determines hair size and shape in mice, suggesting potential avenues for addressing hair loss.
74 citations
,
January 2013 in “Expert Opinion on Biological Therapy” This review discusses recent advances in hair follicle biology, regeneration, and tissue engineering, highlighting emerging therapeutic opportunities, and reports no new experimental results.
136 citations
,
January 2013 in “International Journal of Trichology” This study found that adding microneedling to minoxidil treatment significantly improved hair growth in men with androgenetic alopecia compared to minoxidil alone across all assessed measures.
22 citations
,
June 2012 in “Journal of Investigative Dermatology” This study found that adiponectin promotes hair growth in cultured human hair follicles, suggesting its receptors could be a target for clinical hair growth strategies.
286 citations
,
June 2012 in “Nature Immunology” In this study, researchers found that mouse hair follicles recruit Langerhans cells by secreting chemokines, acting as key portals for these cells in both mice and humans.
270 citations
,
March 2012 in “Dermatologic Surgery” This study found that autologous platelet-rich plasma increased hair growth potential by enhancing dermal papilla cell proliferation and stimulating key signaling pathways in both cell cultures and mice models.
53 citations
,
September 2011 Other common signs, not just the well-known immune cells around hair bulbs, are important for diagnosing hair loss from alopecia areata.
499 citations
,
September 2011 in “Cell” This study found that intradermal adipocyte lineage cells in mice are necessary and sufficient to activate follicular stem cells, highlighting their role in regulating skin stem cell activity.
294 citations
,
February 2011 in “Cell” Nephronectin helps attach muscle cells to hair follicles.
717 citations
,
June 2010 in “Nature” This study identified key genetic regions associated with alopecia areata, highlighting both acquired and innate immune involvement, with a novel link to the upregulation of ULBP ligands in autoimmune disease.
134 citations
,
January 2010 in “Biomedical research” This study found that subcutaneous administration of conditioned medium from adipose-derived stem cells promoted hair growth in mice, and hypoxia enhanced this effect by altering growth factor secretion.
88 citations
,
June 2009 in “Cleveland Clinic Journal of Medicine” This article reviews various causes of diffuse hair loss, highlighting the importance of identifying triggers through thorough examination for effective treatment and emphasizing patient education in management; it reports no new clinical findings.
81 citations
,
April 2009 in “Journal of Investigative Dermatology” This review discusses the shedding phase of the hair cycle, known as exogen, and reports no new findings while analyzing related processes like club fiber formation and release.
29 citations
,
July 2008 in “Journal of Cutaneous Pathology” This study found that follicular streamers are mostly present in non-scarring alopecia cases, and tracking their location can improve diagnosis accuracy.
253 citations
,
December 2007 in “Journal of Investigative Dermatology” This study suggests that human hair follicles may actively suppress natural killer cells, which contrasts with the observed defects in NK cell regulation in alopecia areata.
127 citations
,
December 2007 in “Journal of Investigative Dermatology” This review examines regenerative hair waves and complex hair cycle domains in transgenic mice, highlighting how these dynamic processes contribute to skin regeneration and the physiological regulation of organs, but reports no new experimental results.
159 citations
,
November 2007 in “American Journal of Pathology” In this study, researchers found that substance P triggered premature catagen development and immune changes in human scalp hair follicles, providing a possible biological link between stress and hair loss conditions like telogen effluvium and alopecia areata.
829 citations
,
May 2007 in “Nature” Hair follicles can regrow in wounded adult mouse skin using a process like embryo development.
375 citations
,
July 2006 in “Journal of Investigative Dermatology” This review discusses the brain-skin connection, the skin's role in stress response, and highlights unmet challenges in understanding stress-induced skin inflammation but reports no new experimental findings.
73 citations
,
June 2006 in “Animal genetics” This study found that a missense mutation in the FGF5 gene is associated with hair-length differences among various dog breeds.
92 citations
,
June 2005 in “Journal of Investigative Dermatology” This study found that the retinoid all-trans retinoic acid induced a catagen-like stage in human scalp hair follicles, suggesting upregulation of TGF-beta2 as a contributing mechanism.
76 citations
,
March 2005 in “Journal of Molecular Medicine” This study found that premature hair loss due to stress does not occur in NK-1 receptor knockout or mast cell deficient mice, suggesting a key role for neurokinin substance P and mast cell interaction in stress-related hair follicle changes.
25 citations
,
June 2004 in “Journal of Investigative Dermatology” This study found that macrophage-stimulating protein (MSP) enhanced hair growth in both human hair follicles cultured in vitro and in mice through the promotion of anagen phase induction.
107 citations
,
September 2002 in “Journal of Investigative Dermatology” This study identified a distinct "exogen" phase in the hair cycle during which hair shedding occurs, primarily coupled with the anagen phase, rather than as part of the telogen phase.
144 citations
,
July 2002 in “Clinical and Experimental Dermatology” This article reviews the concept of telogen effluvium and emphasizes the importance of identifying triggers and using diagnostic investigations to determine the cause of hair loss, without reporting new results.
90 citations
,
January 2002 in “Dermatology” This study describes the kenogen phase, where hair follicles rest after shedding, and finds its duration and frequency are greater in individuals with androgenetic alopecia, potentially contributing to baldness.
125 citations
,
September 2001 in “The FASEB Journal” This study demonstrated that stress inhibited hair growth in mice, likely through substance P-dependent activation of immune cells, highlighting a brain-hair follicle connection.
157 citations
,
July 2001 in “British Journal of Dermatology” In this study, the prevalence of androgenetic alopecia among Korean men and women was found to be lower than in caucasians, with Korean men showing more frontal hairline preservation and a higher incidence of 'female pattern' hair thinning.
56 citations
,
January 2001 in “Dermatology” This study introduces the concept of teloptosis, which influences hair shedding during the telogen phase and affects hair density, highlighting that early or delayed teloptosis has noticeable effects.
73 citations
,
November 2000 in “Proceedings of the National Academy of Sciences of the United States of America” This study demonstrated that anagen can be induced in Stat3-disrupted mice, suggesting that both Stat3-dependent and independent pathways, possibly involving PKC, mediate hair cycle progression with required PI3K activation.
231 citations
,
December 1999 in “Journal of Investigative Dermatology” This study found that the volume of a hair follicle's dermal papilla is strongly correlated with its size, primarily due to the number of cells it contains and the volume of extracellular matrix.
23 citations
,
September 1999 in “Archives of Dermatology” Chronic telogen effluvium is a common hair loss condition with specific characteristics and treatment options.
57 citations
,
November 1998 in “Wound Repair and Regeneration” This research observed that dermal papilla cells have the potential to regenerate hair bulbs under preferred environmental conditions when associated with dermal sheath cells or exposed to specific growth factors.
179 citations
,
September 1998 in “BMJ” This article reviews the pathogenesis, genetic basis, and recent treatment breakthroughs for androgenetic alopecia but reports no new clinical findings.
19 citations
,
February 1998 in “Cellular Immunology” Hair growth phase in mice weakens certain immune responses.
75 citations
,
October 1996 in “Dermatologic Clinics” This review examines chronic telogen effluvium, highlighting its distinctive features and the need for reassurance about its non-progressive nature, but reports no new clinical results.
19 citations
,
July 1993 in “The journal of investigative dermatology/Journal of investigative dermatology” The researchers reported that hair follicle germinative epidermal cells can form complex structures when associating with papilla cells in culture, unlike other types of epidermal cells.
13 citations
,
May 1993 in “International Journal of Dermatology” This article presents a theory on the causes and development of telogen effluvium and reports no new clinical findings.
25 citations
,
December 1992 in “Seminars in cell biology” This review discusses how epidermal Langerhan's cells and dermal cells may influence keratinocyte environments, potentially aiding in the formation of stem cell niches and cellular variety in the basal layer, without providing novel results.
13 citations
,
August 1991 in “The Journal of the American Osteopathic Association” This research found evidence of inflammatory involvement in androgenetic alopecia, with higher deposition of certain immune components in the scalp of affected patients compared to those without baldness.
666 citations
,
September 1977 in “British Journal of Dermatology” This article presents a classification system for stages of female-pattern androgenetic alopecia to aid early diagnosis and mentions existing systems for rare male-pattern cases, but reports no new clinical results.
119 citations
,
November 1969 in “Journal of Ultrastructure Research” Macrophages help break down collagen around hair follicles during hair growth.
