Variation of Stratum Corneum Biophysical and Molecular Properties with Anatomic Site
Journal Title: The AAPS Journal - Year 2012, Vol 14, Issue 4
Abstract
Several serine protease enzymes are known to be involved in both normal desquamation and the inflammatory processes of the skin. Alteration in the activity of these proteases should also affect corneocyte maturity and size as well as stratum corneum thickness. The aim of the present work was to characterise the baseline changes in corneocyte size, corneocyte maturity, selected protease activity (specifically, Kallikreins-5 and 7, tryptase), protein content and trans-epidermal water loss (TEWL) as a function of anatomic site. The anatomic sites investigated were: cheek, abdomen, wrist and mid-ventral forearm. TEWL values were highest for the cheek (p < 0.05). The TEWL values were also significantly higher (p < 0.05) for cheek and wrist compared with other sites. Protein content was significantly lower for wrist (p < 0.05) compared with other sites. Corneocyte maturity and surface area were significantly (p < 0.05) lower for cheek and wrist compared with other sites. An excellent correlation (r2 = 0.99) was obtained for maturity and surface area measurements. Kallikrein-5 and tryptase activity were significantly higher for the cheek compared with other sites but Kallikrein-7 values were uniform across sites. The findings have significant implications for skin permeability to drugs and other substances such as environmental toxins depending on the anatomic site of delivery or exposure.
Authors and Affiliations
Diar Mohammed, Paul J. Matts, Jonathan Hadgraft, Majella E. Lane
Role of animal models in the study of drug-induced hypersensitivity reactions
Drug-induced hypersensitivity reactions (DHRs) are a major problem, in large part because of their unpredictable nature. If we understood the mechanisms of these reactions better, they might be predictable. Their unpredi...
Drug Absorption Modeling as a Tool to Define the Strategy in Clinical Formulation Development
This article inadvertently failed to include two of the theme issue guest editors. The complete listing of the guest editors is shown in this erratum.
Translating Human Effective Jejunal Intestinal Permeability to Surface-Dependent Intrinsic Permeability: a Pragmatic Method for a More Mechanistic Prediction of Regional Oral Drug Absorption
The online version of this article (doi:10.1208/s12248-015-9758-0) contains supplementary material, which is available to authorized users.
Pharmacodynamic Modeling of Sequence-Dependent Antitumor Activity of Insulin-like Growth Factor Blockade and Gemcitabine
The online version of this article (doi:10.1208/s12248-011-9308-3) contains supplementary material, which is available to authorized users.
Ajulemic acid (IP-751): Synthesis, proof of principle, toxicity studies, and clinical trials
Ajulemic acid (CT-3, IP-751,1’,1’-dimethylheptyl-Δ8 acid) (AJA) has a cannabinoid-derived structure; however, there is no evidence that it produces psychotropic actions when given at therapeutic d...