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Updated: Jan 27, 2026

Isolation and Culture of Neural Crest Stem Cells from Human Hair Follicles
Published on: April 6, 2013
Histopathology of aging of the hair follicle
Angel Fernandez-Flores1,2,3, Marcela Saeb-Lima4,5, David S Cassarino6
1Department of Cellular Pathology, Hospital El Bierzo, Ponferrada, Spain.
Abstract:
Hair follicles experience several changes with aging, the most noticeable of which is graying of the hair shaft due to loss of melanin. Additional changes in the diameter and length of the hair have contributed to the concept of senescent alopecia, which is different from androgenetic alopecia according to most. Graying happens in most individuals, although in different grades and starting at different ages. It is related to a decrease in the number and activity of the melanocytes of the hair bulb, which eventually completely disappear from the bulb of the white hair. Residual non-active melanocytes remain in the outer root sheath and in the bulge, which allows for repigmentation of the hair under certain stimuli or conditions.
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