PHYSICAL AND BIOCHEMICAL MAKE UP OF THE STRATUM CORNEUM

PHYSICAL AND BIOCHEMICAL MAKE UP OF THE STRATUM CORNEUM

The stratum corneum (S.C.) is a layer of the skin that is supposed to keep out excess water and pathogens trying to permeate the dermis (Agner, 2016; Smedens et al., 2016). The layer has lipids that aid the layer act as a barrier to water, thus keeping the body hydrated (Smedens et al., 2016). The lipid layer is made up of coenocytes, which are the anucleated keratinocytes that form the flat cells that form the extracellular membrane of the stratum corneum (Murphrey et al., 2020). The flat cells are arranged in a brick and mortar style to protect the skin from the environment (Goleva et al., 2019). The stratum corneum has to have linoleic acid, which prevents crystallization of the lipid hydrocarbons preventing loss of the barrier (Popa et al., 2018). The SC also has the cornified cell envelope that provides physical resistance and makes the skin waterproof (Mohd et al.). The overall structure of S.C. is mainly lipids, enzymes, and natural moisturizing factors.

The lipids in the SC are 50% ceramides, 10-20% fatty acids, and 25% cholesterol (Moore &Rawlings, 2017). The ceramides fuse the corneocytes to form a protective layer that prevents water movement (Coderch et al., 2015). The skin lipids are formed by sebocyte, keratinocyte, and skin microbiome (Jia et al., 2018; Cui et al., 2016).

Crystal microdermabrasion removes the stratum corneum, leaving the skin susceptible to infection (Shah et al., 2020). These include acne, atopic dermatitis, and psoriasis (Shin et al., 2018; Danso et al., 2017; Joo et al., 2015). Crystal microdermabrasion removes the stratum corneum, which means that the skin becomes more permeable (Lee & Friedman, 2016; Berkers et al., 2018). The use of moisturizers can repair the barrier function of the stratum corneum. They temporarily block water loss (Elias et al., 2019).

References

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