Cutaneous barrier function

Halkier-Sorensen L, Thestrup-Pedersen K (1991) The relationship between skin surface temperature, transepidermal water loss and electrical capacitance among workers in the fish processing industry comparison with other occupations. A field study. Contact Dermatitis 24 345-355 Halkier-Sorensen L, Menon GK, Elias PM, Thestrup-Pedersen K, Feingold KR (1995) Cutaneous barrier function after cold exposure in hairless mice a model to demonstrate how cold interferes with barrier homeostasis among workers in the fish-processing industry. Br J Dermatol 132 391-401... 

Stratum corneum hydration and cutaneous barrier function Combined use of corneometry and evaporimetry... 

Holleran, W.M., Takagi, Y., Menon, G.K., Legier, G., Feingolg, K.R., and Elias, P.M. Processing of epidermal glucocerebrosidase is required for optimal mammalian cutaneous permeability barrier function./. Clin. Invest. 91 1656-1664(1993). 

Seasonal changes affect the condition of normal skin and may trigger various cutaneous disorders.28,29 In common dermatitis, a decline in barrier function often parallels the increased severity of clinical symptomatology. All these conditions tend to worsen during the winter season when humidity is low.30,31 Abundant indirect evidence indicates that decreased humidity precipitates these disorders, whereas, in contrast, increased skin hydration appears to ameliorate these conditions. The mechanisms by which alterations in relative humidity might influence cutaneous function and induce cutaneous pathology are poorly understood. 

As described previously, one can induce dry, scaly skin, which shows features very similar to dermatitis such as atopic dermatitis and psoriasis. Use of this experimentally induced dry skin should enable the discovery of a new clinical methodology to cure or care for skin problems. Recently, several excellent in vitro skin models have been reported. Although they are also very useful models for the study of cutaneous metabolism, their function and microstructure are still different from those of intact skin. On the other hand, the mechanisms underlying abnormal desquamation, that is, scaling in the dry skin such as atopic dermatitis, are not completely known. Sato et al. reported55 the inhibition of protease in the SC induced scale without affecting epidermal mitosis. This result seems to be no direct relationship between skin surface appearance and epidermal proliferation. However, decline of SC barrier function induced epidermal hyperplasia, as described earlier.30 The loss of water content from SC also induced epidermal DNA synthesis.30 Further mechanistic studies on each of the dry skin features are required. 

Elias, P.M. and Brown, B.E., The mammalian cutaneous permeability barrier defective barrier function in essential fatty acid deficiency correlates with the abnormal intercellular lipid deposition, Lab. Invest., 39, 574, 1978. 

Monteiro-Riviere, N. A., Inman, A. O., and Riviere, J. E. Development and characterization of a novel skin model for cutaneous phototoxicology. 10, 235-243,1994. Monteiro-Riviere, N. A. Anatomical factors affecting barrier function. In Marzulli, F. N., and Maibach, H. I. (Eds.). Dermatotoxicology, Taylor Francis, Washington, D.C., 1996, Chapter 1, pp. 3-17. 

High antibacterial effect restrain the early occurrence of dandruff does not weaken the cutaneous metabolic and barrier function of the skin... 

Benfeldt, E., Serup, J., and Menne, T., 1999, Effect of barrier perturbation on cutaneous salicylic acid penetration in human skin in vivo pharmacokinetics using microdialysis and non-invasive quantification of barrier function, Br. J. Dermatol., 140, 739-748. 

Transepidermal water loss (TEWL) can be considered a determinant indicative of the functional state of the cutaneous barrier (Wilson and Maibach, 1982 Maibach et al., 1984 Rougier et al., 1989) and provides a method for assessing macroscopic changes in the barrier properties of the SC (Abrams etal., 1993). Biophysical investigations suggest that the SC lipid domains are the primary barrier to both water loss and the penetration of compounds through the skin (Van Duzee, 1971 Kalia etal., 2001). Therefore, measurement of TEWL is a relevant parameter for the... 

Ceramides are the main constituents of the lipid lamellas present in the intocellular domains of the stratum comeum from human skin. They have a main role in the structure and the barrier flmction of the skin, vdiich is fimdamental in the sensitive skin. Recent studies have demonstrated that the liposome structures finmed widi internal wool lipids with a relevant amount of ceramides provide bodi a reinforc ent of the barrier function of the skin and an increase of the cutaneous hydration (1,2). 

Recent studies have demonstrated that foe liposome structures formed with foe lipids extracted fiom wool provide a reinfotcement of foe barrier function of the skin and an increase of foe cutaneous hydration, as well as a repair effect of these prop es in chemical or mechanical damaged skin (1, IS). 

Wood LC, Jackson SM, Elias PM, Grunfeld C, Feingold KR (1992) Cutaneous barrier perturbation stimulates cytokine production in the epidermis of mice. J Clin Invest 90 482-487 Wood LC, Feingold KR, Sequeira-Martin SM, Elias PM, Grunfeld C (1994) Barrier function coordinately regulates epidermal IL-i and IL-i receptor antagonist mRNA levels. Exp Dermatol 3 56-60... 

The skin not only is a barrier to restrict diffusion of chemicals into the body, it is also an organ that can metabolize a variety of topically applied substances before they become systemically available. The skin has many of the same enzymes as the liver. The activities of several cutaneous enzymes in whole skin homogenates have been measured and compared to hepatic activity in the mouse. The activities of the enzymes in the whole skin homogenates were typically 2-6% of the hepatic values. However, there is evidence that the enzymes are present primarily in the epidermis. Because the epidermis makes up only 2-3% of the total skin, the real activities may range from 80% to 240% of those in the liver. Enzyme systems present include a qrtochrome P-450 system and a mixed-function oxidase system. 

Potentially severe adverse effects can result from systemic administration of cholinomimetic drugs, and none should be administered by intramuscular or intravenous injection. If significant amounts of these drugs enter the circulation, nausea, abdominal cramps, diarrhea, salivation, hypotension with reflex tachycardia, cutaneous vasodilation, sweating, and bronchoconstric-tion can result. Pilocarpine can cross the blood-brain barrier and affect cognitive function. Even the topical application of cholinomimetics to the eyes can present... 

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