TLDR Human hair is complex and grows in cycles starting from embryonic life.
The document detailed the ultrastructure, function, and formation of hair, focusing on the cuticle, cortical, and medullary cells. Cuticle cells overlapped in a specific pattern, contributing to the surface properties of mammalian fibers. Cortical cells were categorized into orthocortical, paracortical, and mesocortical types based on staining characteristics. The medulla, present in coarser hairs, contained vacuoles and medullary granules. Intercellular connections between various cell types were crucial for the mechanical and chemical properties of fibers. The study highlighted the importance of these cellular structures in applications ranging from textiles to biodegradation.
135 citations,
October 1997 in “Journal of biological chemistry/The Journal of biological chemistry” Trichohyalin is modified by enzymes to form strong structures in hair cells.
28 citations,
October 1985 in “The Journal of Cell Biology” Researchers isolated and identified structural components of human hair follicles, providing a model for studying hair formation.
90 citations,
January 1979 in “International review of cytology” Wool follicles are complex, involving interactions between different cell types and structures.
191 citations,
November 1959 in “Annals of the New York Academy of Sciences” Hair and wool have complex microscopic structures with microfibrils and varying cystine content.
45 citations,
August 2018 in “Stem Cells International” Stem cells, especially from fat tissue and Wharton's jelly, can potentially regenerate hair follicles and treat hair loss, but more research is needed to perfect the treatment.
29 citations,
January 2021 in “Journal of Investigative Dermatology” Fat under the skin releases HGF which helps hair grow and gain color.
1 citations,
October 2012 in “Elsevier eBooks” Skin stem cells can help improve skin repair and regeneration.
4 citations,
August 2023 in “Nature Communications” Mouse zigzag hair bends form due to a 3-day cycle of changes in hair progenitors and their environment.
1 citations,
September 2023 in “eLife” TLR2 is important for hair growth and can be targeted to treat hair loss.
205 citations,
August 2007 in “Experimental Cell Research” Stem cell niches are crucial for regulating stem cell renewal and differentiation, and understanding them can help in developing regenerative therapies.
