What is Stratum Corneum?
Stratum corneum is the farthest of the five layers of the epidermis - the upper layer of the skin. Stratum corneum is also known as the stratum corneum epidermidis, horny layer, keratin layer and corneal layer, is responsible for providing protective barriers against environmental damage, penetration, toxins and microorganisms and maintaining moisture and lubrication. Stratum corneum consists of corneocytes, corneodesmosomes, keratinocytes, enzymes, lipids and natural moisturizing factor (NMF) and plays a complicated and critical role in skin health. Granulosum, Stratum Licidum and Stratum Corneum. Especially the stratum corneum consists of dead or dying cells containing keratin. In general, it is responsible for the appearance, feeling and health of the skin. Each corneocyte has about one micron thick, which is about 1/25 000 inches (about 0.001 mm). The thickness may vary according to age and location. These proteins interleave, creating a strong connection between cells. SpoHanking, called corneodesmosomes, contributes to the impermeability of the skin. Corneodesmosom degradation leads to peeling or sliding the skin - a process that is not well understood.
keratin is produced in cells called keratinocytes, which make up 90 percent of skin cells. As these cells ripen, they push towards the surface of the skin, dry and lighten. People run around 40,000 to 50,000 skin cells every day. Keratin is a strong fibrous protein that gains its strength from the component of cysteinudisulphide - a compound that allows keratin to form disulphide bridges. The number of created disulphide bridges determines whether the keratin layer is as hard as hoof or soft as leather.
keratinocytes also contain lamellar bodies that are formed in the lower layers of the skin called stratum spinosum and stratum granulosum. When keratinocytes migrate to stratus corneum, enzymes cause lamellar bodies to release free fatty acidsand ceramides. Ceramides regulate the growth and change of cells and apoptosis - also called programmed cellular death. Fatty acids and ceramides also combine to form a layer of protective lipid barriers.
about 20 to 30 percent of corneocyte weight consists of NMF. NMFs are water -soluble compounds that occur only in Corneum layer. In general, the NMF takes water from the air and the surrounding tissues and ensures that the outer layer of the skin remains hydrated despite the conditions it is exposed. Lipid layer created by vlamellar bodies help seal corneocyte to prevent moisture loss and maintain the skin with soft and elastic.