Section III: Optimizing Skin Barrier Function Agner T (ed): Skin Barrier Function. Curr Probl Dermatol. Basel, Karger, 2016, vol 49, pp 112–122 (DOI: 10.1159/000441586)

Treatments Improving Skin Barrier Function Marie Lodén Eviderm Institute AB, Solna, Sweden

Moisturizers affect the stratum corneum architecture and barrier homeostasis, i.e. topically applied ingredients are not as inert to the skin as one might expect. A number of different mechanisms behind the barrier-influencing effects of moisturizers have been suggested, such as simple deposition of lipid material outside the skin. Ingredients in the moisturizers may also change the lamellar organization and the packing of the lipid matrix and thereby skin permeability. Topically applied substances may also penetrate deeper into the skin and interfere with the production of barrier lipids and the maturation of corneocytes. Furthermore, moisturizing creams may influence the desquamatory proteases and alter the thickness of the stratum corneum. © 2016 S. Karger AG, Basel

Clinical consequences of potential differences in the efficacy of moisturizers include differences in hydrating properties, effects on visible dryness symptoms and, even more importantly, the likelihood of reduced risks of eczema outbreak in patients with atopic dermatitis (AD). Restoring skin barrier function, e.g. in people with defects in the filaggrin gene, may therefore help to prevent the development of atopic eczema, and halt the development and progression of allergic disease. Evi-

dence from randomized studies also showed that a moisturizer with barrier-improving properties; i.e. a moisturizer lowering transepidermal water loss (TEWL) and reducing the susceptibility to irritation, also delays relapse of eczema in patients with AD and hand eczema. In a worst-case scenario, treatment with moisturizing creams could increase the risks for eczema and asthma. Moisturizing creams suitable to atopic skin are expected to demonstrate absence of barrier-deteriorating properties.

Skin Barrier Function

In summary, the increased understanding of the interactions between topically applied substances and the epidermal biochemistry will enhance the possibilities to tailor proper skin care. The skin has several barrier functions, for example against ultraviolet exposure, microbes and diffusion of chemicals. The term ‘improvement in skin barrier function’ has grown in importance during the last decades among consumers, patients, dermatologists and those involved in the development of topical formulations. The improvement in skin barrier function is recognized as a more healthy-looking and less sensitive skin. Downloaded by: Univ. of California San Diego 198.143.33.49 - 4/1/2016 7:12:51 AM

Abstract

The improvement may be observed at different sites of the skin with different sustainability. For example, covering of the surface with emollients will temporarily reduce signs of dryness and improve the appearance, whereas deeper effects on the intercellular penetration pathways may have a more long-standing effect on the risks for eczema. The findings that permeability barrier abnormalities drive disease activity in inflammatory dermatoses have also grown the interest for treatments which improve skin barrier function [1]. In patients with AD, where the barrier is significantly impaired, the Dermatology Life Quality Index is low [2] and the willingness to pay for complete healing is comparable to that for relief of other serious medical conditions, e.g. angina pectoris,

Treatments Improving Skin Barrier Function Agner T (ed): Skin Barrier Function. Curr Probl Dermatol. Basel, Karger, 2016, vol 49, pp 112–122 (DOI: 10.1159/000441586)

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Fig. 1. Simple schematic representation of a moisturizer as a typical oil-in-water emulsion, where the big circles (yellow; see online version for colors) denote fats/oils (10–30%) whose surfaces are covered with emulsifiers (2–10%). In the water phase (50–80%; blue), the dots (red) represent the preservatives (0.3–2%), the long black threads represent polymers used as thickeners (0.2–2%) and the drops (blue) represent the humectants (0.5– 10%). Other typical additives are stabilizers (antioxidants/chelators), fragrances and botanical ingredients (usually

Treatments Improving Skin Barrier Function.

Moisturizers affect the stratum corneum architecture and barrier homeostasis, i.e. topically applied ingredients are not as inert to the skin as one m...
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