Senile xerosis

The characteristics of hydration level and barrier function of SC in various types of dry skin were reviewed and summarized in Table 9.3. They are senile xerosis, seasonal allergic rhinitis, ichthyosis valgaris, and experimentally induced dry skin including atopic xerosis and dry skin by hemodialysis. The water content decreased in every type of dry skin and the free amino acids content also decreased corresponding to the decrease of the water content. However, the TEWL or the ceramide levels showed no clear tendency throughout every type of dry skin, especially ceramides showed higher or lower value even though the water content in SC was consistently lower in every type of dry skin. 

Takahashi, M. and Tezuka, T., The content of free amino acids in the stratum corneum is increased in senile Xerosis, Arch. Dermatol. Res., 295, 448 -52, 2004. 

However, a recent publication from Takashashi and Tezuka has suggested that the content of FAA in the SC is actually increased in both senile xerosis and in normal aged skin compared to young.87 Indeed these observations are consistent with earlier observations on the age-related increase in the levels of certain FAA primarily found in filaggrin (serine, glutamic acid, glycine) made by Jacobsen.56... 

Tezuka, T. Electron-microscopic changes in xerosis senile epidermis. Its abnormal membrane-coating granule formation. Dermatol. 166 57-61 (1983). 

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