Human skin, permeability

Kahns, A. H., Moss, J., Bundgaard, H., Human skin permeability studies... 

Pugh WJ, Hadgraft J (1994) Ab initio prediction of human skin permeability coefficients. Int J Pharm 103 163-178. 

Abraham MH, Martins F (2004) Human skin permeability and partition general linear free-energy relationship analysis. J Pharm Sci 93 1508-1523. 

Lim CW, Fujiwara S, Yamashita F, Hashida M (2002) Prediction of human skin permeability using a combination of molecular orbital calculations and artificial neural network. Biol Pharm Bull 25 361-366. 

Dearden J.C., Cronin, M.T.D., Patel, H., and Raevsky, O.A., QSAR prediction of human skin permeability coefficients, J. Pharm. Pharmacol., 52 (Suppl.), 221, 2000. 

A suitable animal model can be used for in vivo pharmacokinetic assessment of a topically applied elastic liposome formulation. Rats and mice are most common but tend to provide an over-estimate compared to human skin as the skin is more permeable. Piglets provide a closer approximation to human skin permeability and have been used for some evaluations of elastic liposomes (9, 34). Appropriate animal ethics committee approval is required. A generalised protocol is outlined in the following section but there can be considerable variation depending on the complexity of information sought, i.e., if the determination of distribution into tissues is required in addition to absorption into the circulation ... 

The degree and nature of the distribution patterns of skin permeabilities was addressed to some extent by Southwell et al. (1984) who investigated both in vitro and in vivo variation in the permeability of human skin between different individuals (interspecimen) and the same individuals (intraspecimen). Based on permeation characteristics for a series of compounds, they concluded that in vitro interspecimen variation was 66 25 percent and intraspecimen variation 43 25 percent. The pattern in vivo was similar, although the overall level of variation was somewhat smaller. This analysis has been extended by assessing the statistical distribution of human skin permeabilities. Williams et al. (1992) examined the permeation of 5-fluorouracil and estradiol through human abdominal skin. Here, where the possibility of... 

QSARs allow for the prediction of biological activities and effects, including the skin permeability coefficient. Careful use of historical data, such as those reported by Hynn (1990) and Vecchia and Bunge (2003a, 2003b), will assist in the development of QSARs for human skin permeability coefficients from in vitro measurements. The most successful QSARs for have been based on the approach taken by Potts and Guy (1992), namely, regression analysis based on two descriptors for hydrophobicity and molecular size. There are a number of hmitations to these QSARs, however namely, they are developed from a data set with hmited chemical heterogeneity and are based on measurements from infinite dose in aqueous solution. Despite this, with an appreciation of the limitations of the models and careful and appropriate use, QSARs may be applied successfully for the prediction of K. ... 

Williams, A.C., Cornwell, PA., and Barry, B.W (1992). On the non-Gaussian distribution of human skin permeabilities. International Journal of Pharmaceutics, 86, 69-77. 

Cladera, J., O Shea, R, Hadgraft, J., and Valenta, C. (2003). Influenee of molecular dipoles on human skin permeability use of 6-ketoeholestanol to enhanee the transdermal delivery of baeitracin, J. Pharm. Sci., 92 1018-1027. 

Figure 15.1 to Figure 15.6 bear many similarities to comparable plots of human skin permeability coefficient data (Vecchia and Bunge, 2002b). It is not surprising that skin from different terrestrial species has similar characteristics of dermal penetration. Several mechanistic trends are consistently observed and also make good chemical sense ... 

Dick, l.P. and Scott, RC. (1992). Pig ear skin as an in-vitro model for human skin permeability. Journal of Pharmacy and Pharmacology, 44 640-645. 

Sato, K., Sugibayashi, K., Morimoto, Y., Omiya, H., and Enomoto, N. (1989). Prediction of the in-vitro human skin permeability of nicorandil from animal data, Journal of Pharmacy and Pharmacology, 41 379-383. 

Wester and Noonan (1980) reviewed several in vivo and in vitro experimental investigations of the relationship of animal and human skin permeability coefficients. An analysis by Wester and Maibach (1986) is so similar to this study that it will is not discussed separately. 

Alkomeah FK, Martin GP, Brown MB. Variability in human skin permeability in vitro comparing penetrants with different physicochemical properties. J Pharm Sci. 2007 96 824-34. 

The use of a faster-growing cell line, MDCK (Madin-Darby canine kidney) cells, appears to be a good replacement for Caco-2 cells (Irvine et al. 1999). The parallel artificial membrane permeation assay (PAMPA) is a rapid in vitro assay, in which transcellular permeation is evaluated (Kansy et al. 1998). PAMPA may also be used to predict oral absorption, blood-brain barrier penetration, and human skin permeability (Fujikawa et al. 2007) by using QSAR models. To our knowledge, neither PAMPA, Caco-2 cell monolayers nor MDCK cells have been used to examine the absorption/permeability of the pyrethroids. The advantages and limitations of the Caco-2 model were reviewed by Artursson et al. (1996) and Delie and Rubas (1997). 

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