Ceramides ; Fatty Liver, Alcoholic ; Humans

Apoptosis ; Ceramides ; biosynthesis ; Sphingomyelins ; metabolism

BACKGROUND: The cornposition and biosynthesis of lipids in human skin have long been of considerable interest. Several authors have reviewed the sampling procedures for collecting skin surface lipid. Composition of extracted skin surface lipid may be variable according to different kinds of solvents. OBJECTIVE: We tried to investigate any differences in skin surface lipid composition using three solvents (hexane,hexane/methanol and ethanol). METHOD: The skin surface lipid was extracted by the cup method. Extracted lipid was weighed and analyzed for lipid composition by HPTLC(high performance thin layer chromatography). RESULTS: Total amounts of lipid extracted by each solvent were not significantly different. The skin was more erythematous and irritated after treatment with hexane/methanol than with hexane. Hexane/methanol was more powerful in extracting epidermal lipids than hexane. CONCLUSION: We confirmed the differences of extracted lipid composition depending on the solvents. Total ceramides and polar lipids may play an important role in the maintenance of the normal barrier function.
Ceramides ; Ethanol* ; Humans* ; Methanol* ; Skin* ; Solvents

Tetraacetyl phytosphingosine (TAPS) is an excellent raw material for natural skin care products. Its deacetylation leads to the production of phytosphingosine, which can be further used for synthesizing the moisturizing skin care product ceramide. For this reason, TAPS is widely used in the skin care oriented cosmetics industry. The unconventional yeast Wickerhamomyces ciferrii is the only known microorganism that can naturally secrete TAPS, and it has become the host for the industrial production of TAPS. This review firstly introduces the discovery, functions of TAPS, and the metabolic pathway for TAPS biosynthesis is further introduced. Subsequently, the strategies for increasing the TAPS yield of W. ciferrii, including haploid screening, mutagenesis breeding and metabolic engineering, are summarized. In addition, the prospects of TAPS biomanufacturing by W. ciferrii are discussed in light of the current progresses, challenges, and trends in this field. Finally, guidelines for engineering W. ciferrii cell factory using synthetic biology tools for TAPS production are also presented.
Sphingosine ; Ceramides ; Metabolic Engineering ; Synthetic Biology

BACKGROUND: Stratum corneum lipids serve as a water retainer as well as permeability barrier by forming a multi-lamellae structure in the stratum corneum. The major constituent of these lipids, ceramides, have been shown to be predominantly associated with both functions. OBJECTIVE: Exposure of human epidermis to ultraviolet(UV) irradiation leads to changes in the physiologic and biochemical features of the skin. In order to investigate the effect of UVB irradiation on the skin barrier function in hairless mice, transepidermal water loss (TEWL) and lipid composition of stratum corneum were evaluated in hairless mice. METHODS: Hairless mice were irradiated 3 times weekly for 3 weeks with suberythemal dose (0.6MED, Group I) and minimal erythemal dose(MED), Group II) of UB. The mice of Group III received high dose of UVB(3MED) on the back in a single exposure. The control was Group IV. TEWL measured by evaporimeter and lipid composition of stratum corneum appraised by high performance thin layer chromatography(HPTLC) were evaluated weekly for 3 weeks. RESULTS: 1. Each time it was measured, the values of TEWL in group I were lower than group IV, but the difference was not significant. The peak value of TEWL in group II was 8.2+/-1.56 g/cm/h on the 7th day. The increase in TEWL was markedly significant at this point(P<0.001). Although the values of TEWL on the 14th and 21th day in group E increased compared with those of the control group, the significance of the values decreased (P<0.05). 2. The peak value of TEWL in group III was 9.88+/-1.13 g/cm/h on the 2nd day, showed a markedly significant increase compared with that of the control group(P<0.001). The values of TEWL decreased to the level of the control group on the 14th day. 3. The lipid(cholesterol sulfate, ceramide and neutral lipid) and total lipid mass in group 1 were insignificantly larger than that of the group IV measured each time. On the 7th and 14th day, the amount of each three lipid and total lipid mass significantly increased (P<0.05). On the 21th day, the amount of ceramide and neutral lipid showed a significant increase(P<0.05), furthermore the total lipid mass increased pronouncedly(P<0.01) in group II. 4. The amount of the 3 kinds of lipid and total lipid mass in group III significantly increased compared with those of the control group on the 2nd day(P<0.05). After the 7th day, no significant difference of the lipid mass except neutral lipid compared with that of the control group was seen. Comparing the 2nd and 14th day, there was a significant decrease in the amount of ceramide and total lipid mass(P<0.05) CONCLUSION: These results results suggest that considerable amount of UVB irradiation given in single or repeated exposure causes the disruption of skin barrier function, but a compensatory increase of skin lipid, especially ceramide, protests it from further damage and also improves skin barrier function.
Animals ; Ceramides ; Epidermis ; Humans ; Mice ; Mice, Hairless* ; Permeability ; Skin*

BACKGROUND: A disruption of the balance between the water content of the stratum corneum (SC) and skin surface lipids may lead to the clinical manifestation of dryness of skin in patients with atopic dermatitis (AD). OBJECTIVE: To determine whether supplementation of gromwell (Lithospermum erythrorhizon), one of herbs used in East Asia in remedies for various abnormal skin conditions, may improve the SC level of hydration and ceramides, major lipid in SC in patients with AD. METHODS: A total of 28 subjects with AD were randomly assigned into two groups: either gromwell group received dextrose contained capsules with 1.5 g of gromwell extracts or placebo group received only dextrose contained capsules for 10 weeks. RESULTS: In contrast to no alteration of SC hydration and ceramides in placebo group, the SC hydration in gromwell group was significantly increased in parallel with an increase of SC ceramides. Furthermore, % increase of SC hydration in gromwell group bore a positive correlation with the clinical severity, which suggests that the increase of SC hydration in gromwell group was more effective as AD was more severe. CONCLUSION: Supplementation of gromwell improves SC hydration in parallel with an increase of ceramides in part.
Capsules ; Ceramides ; Dermatitis, Atopic ; Far East ; Glucose ; Humans ; Lithospermum ; Skin

Ceramides ; physiology ; Physiological Phenomena ; radiation effects ; Ultraviolet Rays

PURPOSE: The purpose of this study was to determine if ceramide, which is known as secondary messenger of programmed cell death (apoptosis), can cause apoptosis in lens epithelial cell (LEC) and if so, to identify the pathway by which apoptosis occurs. METHODS: After LECs were exposed to various concentrations of ceramide and phytoceramide, we evaluated the resulting apoptosis response using the Hoechst-EthD stain and Annexin stain. To search for the apoptosis pathway, LECs were preincubated in various concentrations of CPP32-like protease inhibitor, specific caspase-8 inhibitor, and specific caspase-9 inhibitor, then treated with ceramide and phytoceramide. We performed LDH assay 12 hours later. Cytochrome c immunostaining was done after exposure to the ceramide and phytoceramide. RESULTS: All kinds of ceramide induced time and concentration dependent apoptosis in LEC. Caspase 8 inhibitor and caspase 9 inhibitor reduced the apoptosis in ceramide VI, phytoceramide II, and phytoceramide VI. In all ceramides, cytochrome c staining was positive. CONCLUSIONS: Ceramide and phytoceramide can cause apoptosis in LEC. Ceramide and phytoceramide may be used to prevent the posterior capsular opacity after cataract surgery.
Apoptosis* ; Caspase 8 ; Caspase 9 ; Cataract ; Cell Death ; Ceramides ; Cytochromes c ; Epithelial Cells* ; Protease Inhibitors

BACKGROUND: The abnormal barrier function in atopic dermatitis(AD) is caused by a reduction in the amounts of ceramides in the intercellular lipids in the stratum corneum(SC). Replenishing the SC via the topical application of ceramides and pseudoceramides leads to effective recovery of the barrier function of skin. OBJECTIVES: An open clinical crossover evaluation was conducted to investigate the effects in AD of a multi-lamellar emulsion(MLE) that contained pseudoceramide(PC-9s). METHODS: The study group included 30 AD patiendaverage age: 4.4 yr, range: 1-8 yr), who applied MLE or a commercial moisturizing cream(CMC, 5% urea) alternately for four weeks each. We divided the subjects into two subgroups and started with different treatments in each subgroup. Treatment efficacy was evaluated using the average subjective satisfaction scores for each symptom and the global clinical response. In addition, the SCORAD(Scoring AD) index was adopted to evaluate the severity of AD as objectively as possible. The patients were evaluated using this index every other week. RESULTS: Although the SCORAD improved in both subgroups, the patients had better results (p<0.05) when applying MLE(31-35% decrease) than CMC(13% increase to 14% decrease). The subjective satisfaction scores of the symptoms and signs of patients, including itching, erythema, and dry skin, were higher in the MLE group than in the CMC group, and the global response to treatment was also better in the MLE group. During the follow-up period, AD improved in all patients. MLE was more effective than CMC in our patients. CONCLUSIONS: The topical application of a multi-lamellar emulsion containing pseudoceramide is an effective regimen for improving symptoms of AD.
Ceramides ; Cross-Over Studies* ; Dermatitis, Atopic* ; Erythema ; Follow-Up Studies ; Humans ; Pruritus ; Skin ; Treatment Outcome

Stratum corneum lipids, which are enriched in sphingolipids, free fatty acids, and cholesterol, are required for epidermal barrier function. When the epidermal permeability barrier is perturbed, the transepidermal water loss returns to normal by 24-48 hours in parallel with the reappearance of stratum corneum lipids, derived from secreted lamellar bodis and accelerated lipid synthesis. Recent evidence shows that topical application of individual lipids interferes with barrier recovery while complete mixtures of cholesterol, fatty acids, and ceramides facilitate recovery after barrier disrupton. Metabolic imbalances and perturbed barrier function can be either the cause or the consequences of the pathobiology of scaling disease. Many skin diseases relating cornification and dryness are indeed related to abnormality of one or several combinations of lipids. Recently the cytokines which have changed during barrier recovery seem to be important in understanding of epidermal lipid homeostasis as well as barrier recovery.
Ceramides ; Cholesterol ; Cytokines ; Fatty Acids ; Fatty Acids, Nonesterified ; Homeostasis* ; Permeability ; Skin Diseases ; Sphingolipids ; Water