TLDR Brg1 is crucial for hair growth and skin repair by maintaining stem cells and promoting regeneration.
In 2013, researchers discovered that Brg1, a chromatin-remodeling enzyme, is essential for hair follicle regeneration and repair. Brg1 regulates hair follicle stem cells by being activated by sonic hedgehog (Shh) signaling, which initiates hair regeneration. It then activates Shh in matrix cells to sustain hair growth, creating a positive feedback loop. Without Brg1, bulge cells are depleted, partly due to increased expression of the cell-cycle inhibitor p27Kip¹. Brg1 also aids in epidermal repair after skin injury. The study, which did not specify the number of mice used, showed that Brg1 is necessary for bulge cell proliferation and Shh expression. The findings highlight a molecular circuit involving Brg1, NF-kB, Gli proteins, and Shh signaling that is crucial for maintaining the stem cell reservoir and promoting tissue regeneration. The study also involved human bulge cell lines, with some experiments conducted in triplicates with N=6 samples each.
396 citations,
May 2011 in “Cell stem cell” Nerve signals are crucial for hair follicle stem cells to become skin stem cells and help in wound healing.
176 citations,
April 2011 in “Science” Hair stem cell regeneration is controlled by signals that can explain different hair growth patterns and baldness.
34 citations,
June 2008 in “In vitro cellular & developmental biology. Animal” Scientists created a long-lasting stem cell line from human hair that can turn into different skin and hair cell types.
829 citations,
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103 citations,
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113 citations,
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949 citations,
January 2001 in “Cell” Adult mouse skin contains stem cells that can create new hair, skin, and oil glands.
1010 citations,
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194 citations,
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231 citations,
October 1999 in “Journal of Clinical Investigation” Activating the Sonic hedgehog gene in mice can start the hair growth phase.
17 citations,
December 2010 in “Journal of Investigative Dermatology” Flightless I protein affects hair growth, with low levels delaying it and high levels increasing hair length in rodents.
