Role of fatty acid transporters in epidermis

Abstract

Skin epidermis is an active site of lipid synthesis. The intercellular lipids of human stratum corneum (SC) are unique in composition and quite different from the lipids found in most biological membranes. The three major lipids in the SC are free fatty acids, cholesterol and ceramides. Fatty acids can be synthesized by keratinocytes de novo and, in addition, need to be taken up from the circulation. The latter process has been shown to be protein mediated, and several fatty acid transporters are expressed in skin. Recent studies of transgenic and knockout animal models for fatty acid transporters and the identification of fatty acid transport protein 4 (FATP4 or SLC27A4) mutations as causative for Ichthyosis Prematurity Syndrome highlight the vital roles of fatty acid transport and metabolism in skin homeostasis. This review provides an overview of our current understanding of the role of fatty acids and their transporters in cutaneous biology, including their involvement in epidermal barrier generation and skin inflammation.

Adipocytes in Skin Health and Disease

“…Two essential FAs that must be obtained from the diet, linoleic acid and a-linoleic acid, and FAs found in fish oil, plants, or systemic delivery of labeled FAs, have been found in epidermal cells (Reynolds et al 1978;Ziboh et al 1986;Schürer et al 1994). In addition, defects in FA transporters can lead to skin barrier defects in mice and ichthyosis in humans (Khnykin et al 2011), supporting an essential role for fatty acids in skin function.…”

“…Within adipocytes, the process of lipolysis hydrolyzes triglycerides into free FA, which can be transferred to surrounding cells (Zimmermann et al 2004). Although keratinocytes can generate FA (Khnykin et al 2011), dietary FAs are necessary for cutaneous biology and it is tempting to speculate that dermal adipocytes provide a local source of fatty acids within the skin. Two essential FAs that must be obtained from the diet, linoleic acid and a-linoleic acid, and FAs found in fish oil, plants, or systemic delivery of labeled FAs, have been found in epidermal cells (Reynolds et al 1978;Ziboh et al 1986;Schürer et al 1994).…”

Chemical Characterization and Antioxidant Activity of Amazonian (Ecuador) Caryodendron orinocense Karst. and Bactris gasipaes Kunth Seed Oils

“…In light of these experimental results, C. orinocense oil could be considered as an eligible source of ω6 with possible application as food supplements for the prevention of cardiovasculares diseases 23 and as cosmetic ingredient for the role of linoleic acid in the formation and improvement of epidermal barrier 24 . Since lauric oils are widely used in natural foods and in oleochemical industries, B. gasipaes oil from Ecuador could be suggested for the same applications 25 .…”

Consistency of the Proteome in Primary Human Keratinocytes With Respect to Gender, Age, and Skin Localization

“…Keratinocytes account for 95% of all cells of the epidermis and hence are of high interest for studying epidermis functions. They are employed, among others, in research on epidermis acidification (2), DNA degradation in skin (3), local immune response in the skin (4), fatty acid transport and metabolism (5), cell-regeneration (6), and differentiation (7)(8)(9)(10), on the role of stem cells in tissue homeostasis and tumor formation (11), as well as integrin functions (12,13) and celladhesion (14). However, the short keratinocyte life cycle of about 4 weeks requires a steady supply of fresh tissue samples, and a concern is that varying constitutional factors such as age, gender, and anatomic site may compromise experimental results.…”