TLDR Changes in keratin make hair follicles stiffer.
Researchers used atomic force microscopy to measure the mechanical properties of the human hair follicle and found significant stiffening within the first millimeter. This stiffening was linked to changes in the keratin network's architecture and composition. In early keratinization stages, the thickening, densification, and increasing orientation of fibers caused the stiffening, while in later stages, intermolecular cross-linking became more important. These findings supported known biological and structural events during hair keratinization and highlighted the connection between the hair follicle's mechanical properties and its multiscale tridimensional organization.
19 citations,
January 2009 in “International review of cell and molecular biology” Hair's strength and flexibility come from its protein structure and molecular interactions.
30 citations,
August 2008 in “The journal of investigative dermatology/Journal of investigative dermatology” TGase 3 helps build hair structure by forming strong bonds between proteins.
117 citations,
August 2005 in “Ultramicroscopy” Human hair's strength and flexibility vary by ethnicity, damage, and treatment.
29 citations,
April 2003 in “Experimental dermatology” Human hair follicles grown in vitro maintain normal keratin patterns and structure.
235 citations,
July 1999 in “Journal of biological chemistry/The Journal of biological chemistry” Human hair is made up of different keratins, some strong and some weak, with specific types appearing at various stages of hair growth.
February 2024 in “ACS applied bio materials” Keratin microspheres might help hair grow.
138 citations,
March 2007 in “Experimental cell research” Only a few hair-specific keratins are linked to inherited hair disorders.
29 citations,
April 2003 in “Experimental dermatology” Human hair follicles grown in vitro maintain normal keratin patterns and structure.
