Alopecia

January 2018 in “ Elsevier eBooks ”

Michael R. Hamblin

androgenic alopecia alopecia areata hair follicle stem cells sex hormones growth factors reactive oxygen species androgens chemotherapy-induced alopecia microRNAs T cells autoantibodies HF-specific antigens AGA AA CIA ROS

Studysummary This chapter reviews various in vitro and laboratory animal models for studying potential therapies for alopecia and reports no new results.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The document from 2018 provides a comprehensive overview of hair growth, hair follicle anatomy, and the role of stem cells in hair cycling, with a focus on various forms of alopecia, particularly androgenic alopecia (AGA) and alopecia areata (AA). It explains the complex signaling involved in hair growth, the impact of sex hormones and growth factors, and the importance of mitochondrial-generated reactive oxygen species in hair follicle morphogenesis. AGA, the most common form of hair loss, is characterized by its patterns, genetic factors, and the role of androgens. The document contrasts AGA with chemotherapy-induced alopecia (CIA), noting that CIA spares stem cells, allowing for hair regrowth post-treatment. It also discusses the discovery of microRNAs and their role in hair loss, the reduced blood flow in balding areas, and the differences between mouse and human skin for research models. The document highlights the genetic associations of AA, the role of T cells and autoantibodies, and the identification of AA-reactive HF-specific antigens. It concludes by discussing the social and psychological impacts of alopecia and the resulting industry for hair loss treatments.

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Regenerative Medicine and Hair Loss: How Hair Follicle Culture Has Advanced Our Understanding of Treatment Options for Androgenetic Alopecia

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218 citations , January 2013 in “The Lancet Oncology”

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54 citations , September 2012 in “The journal of investigative dermatology/Journal of investigative dermatology”

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300 citations , August 2012 in “Seminars in Cell & Developmental Biology”

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research Hair Follicle Stem Cell Differentiation Is Inhibited Through Cross-Talk Between Wnt/β-Catenin and Androgen Signaling in Dermal Papilla Cells From Patients With Androgenetic Alopecia

95 citations , January 2012 in “British Journal of Dermatology”

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research Trichohyalin Is a Potential Major Autoantigen in Human Alopecia Areata

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253 citations , December 2007 in “Journal of Investigative Dermatology”

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research Genomewide Scan for Linkage Reveals Evidence of Several Susceptibility Loci for Alopecia Areata

143 citations , January 2007 in “The American Journal of Human Genetics”

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research Phenotypic Analysis of T-Cells in Extensive Alopecia Areata Scalp Suggests Partial Tolerance

21 citations , December 2005 in “The journal of investigative dermatology/Journal of investigative dermatology”

This study demonstrates that T-cell responses in extensive alopecia areata scalp may be aberrantly regulated, with reduced cytokine production but activated phenotype, providing insight into the disease's immune mechanisms.

research Rooster Feathering, Androgenic Alopecia, And Hormone-Dependent Tumor Growth: What Is In Common?

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research Transplants from Balding and Hairy Androgenetic Alopecia Scalp Regrow Hair Comparably Well on Immunodeficient Mice

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research The Extract of Thuja Occidentalis Semen Inhibited 5α-Reductase and Androgenetic Alopecia in B6CBAF1/J Hybrid Mice

47 citations , April 2003 in “Journal of dermatological science”

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69 citations , July 2002 in “Clinical and Experimental Dermatology”

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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.

research Vertex Balding, Plasma Insulin-Like Growth Factor 1, and Insulin-Like Growth Factor Binding Protein 3

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This study found that older men with vertex balding had lower levels of IGFBP-3 and higher levels of IGF-1 in their plasma.

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71 citations , January 1998 in “Pathobiology”

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research Doxorubicin-Induced Hair Loss in the Angora Rabbit: A Study of Treatments to Protect Against Hair Loss

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