Biology of Human Hair: Know Your Hair to Control It

Abstract

Hair can be engineered at different levels-its structure and surfacethrough modification of its constituent molecules, in particular proteins, but also the hair follicle (HF) can be genetically altered, in particular with the advent of siRNA-based applications. General aspects of hair biology are reviewed, as well as the most recent contributions to understanding hair pigmentation and the regulation of hair development. Focus will also be placed on the techniques developed specifically for delivering compounds of varying chemical nature to the HF, indicating methods for genetic/biochemical modulation of HF components for the treatment of hair diseases. Finally, hair fiber structure and chemical characteristics will be discussed as targets for keratin surface functionalization.

Human Hair and the Impact of Cosmetic Procedures: A Review on Cleansing and Shape-Modulating Cosmetics

“…These cyclic changes comprise rapid remodeling of both epithelial and dermal components through the activation of differentiation of stem cells [29][30][31][32]. All body hairs undergo a similar life cycle, although its extent, duration of its phases and the length of individual fibers vary between different body areas and between persons, depending on All body hairs undergo a similar life cycle, although its extent, duration of its phases and the length of individual fibers vary between different body areas and between persons, depending on genetic programming, gender, age and health status [34]. Furthermore, the extent of the cycle phases determines the length of the hair and its replacement rate [1].…”

“…Each layer itself can comprise numerous individualized cell layers characterized by specific programs of differentiation [32]. genetic programming, gender, age and health status [34]. Furthermore, the extent of the cycle phases determines the length of the hair and its replacement rate [1].…”

Towards a body hair atlas of women of caucasian ethnicity

“…Hair is an important feature of mammalian body surfaces. From a biological point of view, mammalian hair fulfils numerous different functions such as protection against environmental trauma, thermoregulation, camouflage, collection of sensory information or social communication . Thus, in most mammalian species, hair is indispensable for survival.…”

Feather keratin hydrolysates obtained from microbial keratinases: effect on hair fiber

“…The cuticle consists of overlapping layers of scales, each about 0.5 μm thick and is composed of β keratin. The cuticle protects the underlying cortex by acting as a barrier [5]. The medulla consists of specialized cells that contain air spaces.…”