Growth Hormone and the Human Hair Follicle

December 2021 in “ International journal of molecular sciences ”

Elijah J. Horesh, Jérémy Chéret, Ralf Paus

growth hormone GH hypertrichosis hirsutism alopecia hair follicle defects recombinant human GH TGF-β2 catagen-inducing growth factor Noonan Syndrome Turner Syndrome Prader–Willi syndrome acromegaly hair loss hair growth recombinant human growth hormone transforming growth factor beta 2

Studysummary This article reviews current knowledge and research gaps on growth hormone in hair follicle biology, highlighting its complex role and suggesting further exploration to reveal nonclassical skin functions. Our plain-language summary of this paper — not a Tressless recommendation.

The paper "Growth Hormone and the Human Hair Follicle" investigates the role of growth hormone (GH) in hair follicle biology. The authors found that excessive GH serum levels can lead to hypertrichosis and hirsutism, while dysfunctional GH receptor-mediated signaling is linked with alopecia and hair follicle defects. Recombinant human GH inhibits female human scalp hair follicles' growth ex vivo, likely by stimulating the expression of the catagen-inducing growth factor, TGF-β2. Conditions leading to GH deficiency, such as Noonan Syndrome, Turner Syndrome, and Prader–Willi syndrome, are associated with hair loss conditions. Conversely, conditions of GH excess, like acromegaly, are associated with increased hair growth. The authors conclude that further research into GH's role in hair follicle biology could guide treatment options for various hair disorders.

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research Growth Hormone Operates as a Neuroendocrine Regulator of Human Hair Growth Ex Vivo

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36 citations , February 2018 in “British Journal of Dermatology”

In this study, researchers found that eccrine sweat glands in human scalp skin are morphologically integrated into the pilosebaceous unit, suggesting they form a common homeostatic tissue environment with adjacent structures.

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This study found that the synthetic thyroid hormone receptor modulator KB2115 significantly prolonged the growth phase of human hair follicles in culture without altering mitochondrial activity, suggesting potential as a safer hair loss treatment compared to traditional thyroid hormones.

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research Both Low Circulating Insulin-Like Growth Factor-1 and High-Density Lipoprotein Cholesterol Are Associated with Hair Loss in Middle-Aged Women

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This study reports that low levels of HDL cholesterol and IGF-1 were associated with a higher risk of hair loss in middle-aged women, but causal relationships remain uncertain.

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92 citations , September 2013 in “Journal of Investigative Dermatology”

This study found that peripheral clock genes, particularly BMAL1 and Period1, modulate human hair follicle cycling, suggesting their potential as therapeutic targets for affecting hair growth.

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95 citations , August 2013 in “Journal of Investigative Dermatology”

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research Safety and Efficacy Analysis of Liposomal Insulin-Like Growth Factor-1 in a Fluid Gel Formulation for Hair-Loss Treatment in a Hamster Model

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72 citations , January 2012 in “Annals of Dermatology”

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