Effect of Lipids on the Aggregation and Permeability of Human Stratum Corneum

Abstract

The role of stratum corneum (SC) constituents in SC barrier properties was assessed directly in vitro in a reaggregated system. Fragments of SC from the sole of the foot (hyperplastic tissue) and from the calf (normal tissue) were reduced, separately, to individual cells and these cells were depleted of lipids by solvent extraction. Lipids taken from the cells themselves or from SC from other areas of the body were then added to the cells. None of the fractions used allowed for reaggregation of plantar SC cells, or of trypsinized calf SC cells. In contrast, calf SC cells reaggregated equally well with all lipids and formed coherent SC sheets. At equal lipid:cell ratios, however, plantar lipid-calf cell SC sheets were about three time more permeable to water than calf lipid-calf cell SC sheets. The effectiveness of the barrier function of the SC sheets was directly proportional to the amount of added lipid. We conclude that in normal SC the extractable lipids are intimately involved in cellular adhesion/dyshesion and in barrier formation.

Preclinical Investigation of the Topical Administration of Phenserine: Transdermal Flux, Cholinesterase Inhibition, and Cognitive Efficacy

“…In the stripped skin studies, the formulation vehicle seemed to have little impact. It has been widely reported that the stratum corneum represents a major barrier to transdermal permeability (Scheuplein and Blank, 1973;Smith et al, 1982;Madison et al, 1987), and as expected, transdermal fluxes of PS were greater through stripped skin than intact skin. Because the barrier integrity of the stratum corneum may be compromised with age and because AD is an age-associated disease, the former was assessed to provide an estimate of maximal permeability.…”

“…1) was used (Addicks et al, 1987;Sclafani et al, 1993) to assess the availability of PS from vehicle, and subsequent transdermal permeability. Because the stratum corneum has been characterized as a major barrier to transdermal permeability (Sheuplein and Blank, 1973;Smith et al, 1982;Madisonet al, 1987) and barrier integrity may be variably affected by age (Ghadially et al, 1995), permeabilities were investigated through both intact and tape-stripped skin. Intact skin or tape-stripped skin was isolated from the back of hairless mice and placed between the donor and the acceptor phase of the flow-through cell, allowing a permeation surface area of 1 cm 2 .…”

Stratum corneum lipids in disorders of cornification: increased cholesterol sulfate content of stratum corneum in recessive x-linked ichthyosis.

“…12, 14). Preliminary evidence also suggests that stratum corneum lipids may be essential for the invisible, orderly process of normal desquamation (15,16 (2). Moreover, the diagnosis ofRXLI was confirmed by prior assay of steroid sulfatase activity in fibroblasts and /or leukocytes (6) (Table I).…”

Skin and Liquid Crystal: A brief review on their similarities

“…It also prevents the uptake of water into animal body, stbilizes the body temperature and also serve as a barrier to chemical and biological attack from the environment. Vast attention has been directed to the water transport through the stratum corneum [3][4][5][6] . Most evidences indicate that the lipids content of the stratum corneum to be the main factor in the stratum corneum barrier to trans dermal …”