• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.53-72
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• 2001

Dry skin is caused mainly by the perturbation of stratum corneum lipids which affected by ageing, change of season, excess use of surfactant and the effect of disease like atopic dermatitis and psoriasis. Intercellular lipid structures in stratum corneum are responsible for the barrier function of mammalian skin. The major lipd classes that can be extracted from stratum corneum are ceramides, cholesterol and fatty acid, which make up approximately 50, 25, 10 percent of the stratum corneum lipid mass, respectively. Small amount of cholesterol sulfate, phospholipids, glycosylceramide and cholesterol esters are also present. Recent studies have shown that application of one or two these lipids to the perturbed skin delays barrier recovery; only equimolar mixtures allow normal recovery. We observed that barrier recovery rate was improved in hairless mouse by topical application of single neutral lipids (ceramide, free fatty acid, cholesterol) and lipid mixtures. Whereas the application of single lipid didn’t allows a significant enhancement comparing with normal barrier repair, the equimolar mixtures of 3 components(including synthetic pseudoceramide PC104) improved barrier repair, as assessed by the transepidermal water loss. At clinical study to the volunteers aged over sixty, skin dryness recuperated by the increase of moisture(capacitance) and the reduction of scaling. Utilization of physiologic lipid mixture containing natural ceramides or synthetic pseudoceramide could lead to new forms of topical therapy for the dryness and dermatoses(e.g., psoriasis, atopic dermatitis and irritant dermatitis).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.3-15
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• 2001

The bilayer forming ability of pseudo-ceramide PC104 in octanoic acid/water/n-octyl $\beta$-D-glucoside mixtures was investigated through the phase diagram. Because of its low solubility in water and of its crystallization, pseudoceramide PC104 was dissolved in octanoic acid, which is nontoxic additive for foods and cosmetics. The mixtures formed four different phases (L1, L2, LC and two phases). Depending on the concentration of PC104 in octanoic acid, the region of each phase was extended or contracted. On the contrary to the region of L2, regions of lamellar phase and L1 phase were expanded. The bilayer-forming ability of PC104 was explained on the basis of concentration of PC104 at interface and interaction between PC104 and octanoic acid. From FT-IR results, it was found that the interactions of PC104’s polar head group with octanoic acid increased as the amount of PC104 in octanoic acid increased. Also emulsion size and size distribution have been studied depending upon the emulsification path. droplets of emulsion prepared from lamellar phase were smaller and more homogeneous compared to those of emulsions formed from L2 phase.

• Biomolecules & Therapeutics
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• v.19 no.1
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• pp.134-139
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• 2011

Sphingosine kinase (SPHK) has a central role to control cell death and cell proliferation, which is suggested as a sphingolipid rheostat by regulating the levels between ceramide and sphingosine 1-phosphate (S1P). Therefore, physiological regulators of SPHK will be a good candidate to develop a new targeted drug. For this purpose, a series of synthetic pseudoceramides were tested by SPHK assay either cell-based or cell-free system. K10PC-5 strongly inhibited SPHK, while K6PC-5 activated SPHK in cell-free system. Specifically, K6PC-5 activated SPHK under the co-treatment with $50\;{\mu}M$ dimethylsphingosine (DMS), a SPHK inhibitor. Collectively, we developed a simple SPHK assay system to find SPHK regulatory pseudoceramide compounds, K10PC-5 and K6PC-5 which may be useful to cancer treatment or immune regulation like FTY720, a synthetic sphingolipid mimetic compound.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.765-779
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• 2003

Physiological lipid mixtures comprised of cholesterol, ceramide and free fatty acid better maintain epidermal homeostasis and have been recently used for dermatoses induced by skin barrier damage, for example for atopic dermatitis and xerotic skin. Itching and dry atopic dermatitis of the skin may be related to altered skin barrier function. In a previous study, the use of multi-lamellar emulsion (MLE), which is a lipid mixtures containing cholesterol, pseudoceramide and free fatty acid, has been shown to accelerate the recovery of the epidermal permeability barrier. In this study, we assessed the efficacy of MLE compared with a currently used anti-itch moisturizer (AIM), the active ingredients of which are menthol and camphor, on barrier recovery after barrier disruption. To clarify the effect of MLE and AIM after acute barrier perturbation, we measured the relation between transepidermal water loss (TEWL) and the barrier recovery rate at 3, 6, 24, and 48 hours after tape stripping hairless mice and then observed changes in the stratum corneum (SC), including the intercellular lipid structure and secretion of lamellar bodies, by electron microscopy. MLE treated skin recover skin barrier function more rapidly, and AIM treated skin delayed barrier repair. Morphological changes in the epidermis, of MLE treated skin revealed well-conserved lipid multi-lamellar structures at 24 h after tape stripping, whereas AIM treated skin showed altered lamellar bilayers within the SC interstices at 48 h. In addition, MLE treated skin showed an increase in the number of LBs and in their secretions and a decrease in the number of SC layers versus AIM treated skin. These results suggest that MLE may accelerate the production of an epidermal permeability barrier in hairless mice by increasing the number and secretion of LB and improve the dryness and itch associated with an altered epidermal permeability barrier.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.1
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• pp.55-68
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• 1999

A muti-lamellar emulsion containing a pseudoceramide, N-Ethanol-2-myristyl/ palmityl-3-oxostearmide/arachidamide(PC-9) has been prepared and its efficacy evaluation has been investigated. In order to prepare a muti-lamellar emulsion, first, the gram ratios of PC-9, fatty acid and cholesterol on the phase diagram to be capable of forming their lamellar liquid crystal structures were determined and secondly, the multi-lamellar emulsion was preprared using glyceryl monostearate and polyoxyethylene glyceryl monosteartate as emulsifers together with above mentioned pseudo-stratum corneum lipid components. Besides natural oils such as olive oil had a tendency to build up the multi-lamellar emulsion. And according as the amount of oil increased in the emulsion, it was observed that the optical anisotropy of “Maltese Cross” which was a typical configuration of multi-lamella mesophase texture diminished. In the dried state of the multi-lamella emulsion, it was examined to transform its emulsion phase into a lamella liquid crystal one. And finally, when the emulsion was applied into a human skin, it was investigated that it had effectiveness in reducing transepidermal water loss (TEWL) of the skin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.345-352
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• 2004

There are two paradigms to explain the atopic dermatitis. The first is outside-inside paradigm and the second is inside-outside paradigm. According to the outside-inside paradigm the best way to treat the atopic dermatitis is recovery of skin barrier function. The barrier function is maintained by the specific structure of stratum corneum, which is constructed from corneocytes and intercellular lipids. In terms of lipid structures of SC in atopic dermatitis and lamellar ichthyosis, they contain more fluid hexagonal gel structures in SC and show deficiencies in free fatty acids, especially long chains and certain ceramides. With this reason, moisturizer which has the lamellar structure and restoring function of intrinsic intercellualr long periodicity phase can maintain and restore the lamellar structure of intercellular lipids in SC. The moisturizers containing ceramide or pseudoceramide also seem to be reasonable therapy for atopic dermatitis and several skin diseases, which interrelated with impaired skin harrier. By the way, according to the inside-outside paradigm, immune response including helper T cells, IgE, eosinophils is related. It is effective treatment of atopic dermititis to restore imbalance between Th1 and Th2 cells. Even though several kinds of immune-suppressor were introduced, these can affect the intrinsic immune function. SPC and S1P, metabolites of ceramide, would be interesting because they have the function of wound healing and immune modulating properties.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.522-532
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• 2010

The aims of the present study were to characterize the effect of glucocorticosteroids (GCs) on the normal canine skin and to evaluate the effect of a lipid mixture (LM), containing cholesterol, pseudoceramide, and free fatty acid, on the steroid-induced damaged skin of dogs. Five beagles were involved and the skin of the back of each dog was topically applied with four kinds of GCs twice daily for 28 days. LM was applied after that period of GCs application. Transepidermal water loss (TEWL), skin hydration, and skin pH were assessed during experimental periods and histopathological evaluation was performed. TEWL was significantly increased, with a maximum increase obtained on day 28 (p < 0.01). Skin pH was significantly decreased, with a maximum decrease obtained on day 28 (p < 0.01). Skin surface hydration was significantly increased on day 3, but values of skin hydration were progressively decreased and finally reached those of baseline. In histology, as results of steroid application, losses of keratin layers in the stratum corneum and edematous changes in the upper parts of dermis, and consequently, thickness of the epidermis and the stratum corneum were decreased. In addition, the numbers of hair follicles were markedly decreased in steroid control as compared to intact control. However, these skin atrophic changes were markedly inhibited by treatment of LM as compared with steroid control in the present study. Moreover, all biophysical parameters were reached to the baseline after LM treatment. These results showed that the topically applied GCs induced skin barrier impairment and a LM should be effective on repair of disturbed skin barrier function in dogs. Therefore, it is concluded that a LM tested in the present study is expected to treat the steroid-induced skin damages.