Desquamation cholesterol sulfate

The elucidation of the molecular genetics RXI has had a major impact on our understanding of stratum corneum turnover. Individuals with RXI lack an enzyme, cholesterol sulfatase,3,4 which catalyzes the transformation of cholesterol sulfate (CS) to cholesterol and free sulfate. As a result there is an accumulation of CS in the stratum corneum intercellular space. Possible mechanisms by which this change in intercellular lipid composition of the stratum corneum can cause disturbances in desquamation, leading to ichthyosis, will be discussed later. 

The composition of the stratum corneum intercellular lipids may have profound effects on desquamation. In addition to modifying effects on, for example, proteolytic enzymes and their substrates,34 lipids may also be directly involved in corneocyte cohesion. The effects of cholesterol sulfate have already been mentioned. In addition to RXI, there are a number of other hereditary diseases with disorders of desquamation associated with disturbances in lipid metabolism. Furthermore, scaling as a result of treatment with lipid-lowering drugs has been observed (for review, see References 1 and 2). 

Sato, J., Denda, M., Nakanishi, J., Nomura, J., and Koyama, J., Cholesterol sulfate inhibits proteases that are involved in desquamation of stratum corneum, J. Invest. Dermatol., Ill, 189, 1998. 

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