Keratin a type of fibrous structural protein called scleroproteins. Keratin is the main structural material that constitutes the hair, scales, nails, feathers, horns, hooves, claws and calluses. It forms the outer layer of the skin in vertebrates and provides protection from damage or stress. Keratin is not soluble in hot or cold water and proteolytic enzymes (enzymes that breakdown the protein molecules).
Keratin proteins can be subdivided into α-keratins and β-keratins, based on their secondary structure.
Keratin is not digested in the digestive system and can be dangerous when ingested. This is the reason that some animals like cats, regurgitate the fur and hair that they swallow along with their food.
Function of keratin:
Clinical significance of keratin:
Diseases of keratin can be broadly categorized under infection, genetic conditions and carcinomas.
Keratin treatments for hair:
Since keratin forms about 95% of the structure of the human hair, keratin supplements, products and treatments are believed to strengthen hair and give it a healthy and a shiny look.
The effects of keratin treatment can vary depending on factors like health of the hair, thickness and the types of keratin treatment used. Keratin treatment helps in smoothening of cells that overlap to form hair strands.
Cuticle, the layers of hair cells, is believed to absorb the keratin applied on hair and makes hair look glossy. Keratin treatment makes the hair easy to manage, style and less frizzy.