Y Takema’s research while affiliated with Kao Corporation and other places

Background: Ceramide is a crucial lipid in the stratum corneum (SC) which maintains the barrier function and hydration of the skin. In atopic dermatitis (AD) patients who have defective skin barrier function, ceramide levels are altered. We previously reported that although the amount of total ceramide was lower in involved skin compared with uninvolved skin of AD patients and with healthy control skin, the amounts of smaller ceramide species of Cer[NS] (<40 total carbons, which are total carbons of both sphingoid base and amide-linked fatty acid), especially Cer[NS] with 34 total carbons (C34-Cer[NS]), were higher. However, the enzyme(s) that produces the higher levels of smaller ceramide species in involved skin of AD patients was unclear. Objective: To identify the enzyme(s) that produces higher levels of smaller ceramide species of Cer[NS] in the involved skin of AD patients. Methods: Eight female Caucasian subjects who were diagnosed with AD on their arms (age range: 21-45 years) were enroled in this study. We compared ceramide levels in the SC and the expression levels of enzymes involved in ceramide metabolism using real-time PCR and immunohistochemistry between involved and uninvolved skin of AD patients. Results: Level of mRNA encoding ceramide synthase 4 (CERS4), which is one of the enzymes that synthesize ceramide from a sphingoid base and an amide-linked fatty acid, was significantly higher in involved skin than in uninvolved skin (P < 0.01). Additionally, the protein expression level of CERS4 in the epidermis was also higher in involved skin compared with uninvolved skin. The expression level of CERS4 correlated with the amount of C34-Cer[NS] (P < 0.01) and the skin hydration value (P < 0.05). Conclusions: The elevated expression level of CERS4 contributes to the increase of C34-Cer[NS] and the impaired SC barrier function in involved skin of AD patients.

Ultraweak photon emission (UPE) is one potential method to evaluate the oxidative status of the skin in vivo. However, little is known about how the daily oxidative stress of the skin is related to skin aging-related alterations in vivo. We characterized the steady state UPE and performed a skin survey. We evaluated the skin oxidative status by UPE, skin elasticity, epidermal thickness and skin color on the inner upper arm, the outer forearm, and the buttock of 70 Japanese volunteers. The steady state UPE at the three skin sites increased with age. Correlation analysis revealed that the steady state UPE only from the buttock was related to skin elasticity, which showed age-dependent changes. Moreover, analysis by age group indicated that b* values of the inner upper arm of subjects in their 20s were inversely correlated with UPE as occurred in buttock skin. In contrast, photoaged skin did not show a clear relationship with steady state UPE because the accumulation of sun-exposure might influence the sensitivity to oxidative stress. These results suggest that steady state UPE reflects not only intrinsic skin aging and cutaneous color but also the current oxidative status independent of skin aging.

The medulla is the innermost structure of the mammalian hair fibre. Unlike most mammals, in man only androgen-dependent sexual hairs, i.e. beard, pubic and axillary hairs, are regularly medullated, while the frequency of medullation in scalp hairs varies among individuals and ethnicities(1,2) . Recently, we reported that out of the 54 human keratins,12 epithelial keratins [comprising members of the outer and inner root sheath (ORS, IRS), the companion layer (cl), and the almost ubiquitously expressed keratin K80(3) , as well as 12 hair cortex keratins] are present in the medulla of beard hairs(4) .

Synopsis The objectives of this study were to identify a plant extract that would improve stratum corneum functions and to elucidate the mechanism(s) involved. Based on the information that stratum corneum functions depend on the level of ceramide in the stratum corneum, we identified a Eucalyptus extract that was able to increase the level of ceramide in human keratinocytes in culture and in human stratum corneum and that improves the stratum corneum water holding and barrier functions. Addition of the Eucalyptus extract to human keratinocytes in culture increased the level of ceramide in a dose‐dependent manner and also increased the biosynthesis of ceramide, glucosylceramide and sphingomyelin. Topical application of the Eucalyptus extract on the dry skin of human subjects induced by acetone and diethylether treatment resulted in a significant increase in ceramide level in the stratum corneum, a significant improvement in its water‐holding function and an improvement in its barrier function. The addition of macrocarpal A, one of the main components of the Eucalyptus extract, to human keratinocytes in culture increased the level of ceramide and the mRNA expression of serine palmitoyltransferase, acid sphingomyelinase, neutral sphingomyelinase, glucosylceramide synthase and glucocerebrosidase in a dose‐dependent manner. Our results indicate that the increased content of ceramides in the stratum corneum may underlie the therapeutic effect of the Eucalyptus extract. Our results also indicate the possibility that macrocarpal A is the key component that stimulates the synthesis of ceramide in the stratum corneum.

Synopsis Scientific evaluation of fabric softener use on the friction of fabrics and on dry skin in real life is very limited. The coefficient of friction of fabrics was measured with a surface tester using model skin and cotton fabrics. The effects and safety of fabric softener-treated T-shirts on subjects with dry skin were evaluated in real-life conditions in the cold and arid environment. Twenty male volunteers with dry skin used T-shirts without softener for 1 week before day 0 and then wore softener-treated T-shirts for 14 days. Effects were evaluated by clinical grading, subjective symptoms, stratum corneum water content (SCWC) and transepidermal water loss (TEWL). A significant decrease in the coefficient of friction of fabrics was detected. A significant improvement in SCWC was observed on the torso, waist and shoulder, but no improvement was found on the inner forearm. There was a slight change in TEWL. The visual grading of dryness improved significantly at all sites, but no significant change was found in subjective symptoms. Our results suggest that fabric softener provides benefits to individuals with dry skin because of the decreased friction of the garments against the skin. It is possible that the softener treatment of fabrics contributes to the state of moisturization of the skin and may work in collaboration with the application of moisturizers. © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Pseudotyping lentiviral vector with other viral surface proteins could be applied for treating genetic anomalies in human skin. In this study, the modification of HIV vector tropism by pseudotyping with the envelope glycoprotein from vesicular stomatitis virus (VSV), the Zaire Ebola (EboZ) virus, murine leukemia virus (MuLV), lymphocytic choriomeningitis virus (LCMV), Rabies or the rabies-related Mokola virus encoding LacZ as a reporter gene was evaluated qualitatively and quantitatively in human skin xenografts. High transgene expression was detected in dermal fibroblasts transduced with VSV-G-, EboZ- or MuLV-pseudotyped HIV vector with tissue irregularities in the dermal compartments following repeated injections of EboZ- or LCMV-pseudotyped vectors. Four weeks after transduction, double-labeling immunofluorescence of beta-galactosidase and involucrin or integrin beta1 demonstrated that VSV-G-, EboZ- or MuLV-pseudotyped HIV vector effectively targeted quiescent epidermal stem cells which underwent terminal differentiation resulting in transgene expression in their progenies. Among the six different pseudotyped HIV-based vectors evaluated, VSV-G-pseudotyped vector was found to be the most efficient viral glycoprotein for cutaneous transduction as demonstrated by the highest level of beta-galactosidase expression and genome copy number evaluated by TaqMan PCR.

Pseudotyping lentiviral vector with other viral surface proteins could be applied for treating genetic anomalies in human skin. In this study, the modification of HIV vector tropism by pseudotyping with the envelope glycoprotein from vesicular stomatitis virus (VSV), the Zaire Ebola (EboZ) virus, murine leukemia virus (MuLV), lymphocytic choriomeningitis virus (LCMV), Rabies or the rabies-related Mokola virus encoding LacZ as a reporter gene was evaluated qualitatively and quantitatively in human skin xenografts. High transgene expression was detected in dermal fibroblasts transduced with VSV-G-, EboZ- or MuLV-pseudotyped HIV vector with tissue irregularities in the dermal compartments following repeated injections of EboZ- or LCMV-pseudotyped vectors. Four weeks after transduction, double-labeling immunofluorescence of β-galactosidase and involucrin or integrin β1 demonstrated that VSV-G-, EboZ- or MuLV-pseudotyped HIV vector effectively targeted quiescent epidermal stem cells which underwent terminal differentiation resulting in transgene expression in their progenies. Among the six different pseudotyped HIV-based vectors evaluated, VSV-G-pseudotyped vector was found to be the most efficient viral glycoprotein for cutaneous transduction as demonstrated by the highest level of β-galactosidase expression and genome copy number evaluated by TaqMan PCR.

Background/aims The human face shows morphological changes with age. Although these changes are generally recognized as wrinkle formation, there have been no quantitative studies of three‐dimensional morphological changes with age in each area of the face. The object of the present study, therefore, was to evaluate age‐related three‐dimensional morphological changes in each area of the face. Methods We obtained replicas using a silicon impression material from eight areas of the face (forehead, eye corners, upper eyelids, lower eyelids, glabella, cheeks, mouth angles, and nasolabial groove) of 136 healthy women, and performed morphological evaluations using a small object type three‐dimensional surface morphology measurement system (Voxelan, NKK Co. Ltd., Japan). Results All parameters examined, with the exception of sWv in the cheeks, increased with age. The correlation between sWp and age was high in the following order: eye corners > mouth angles > glabella > nasolabial groove > upper eyelids > lower eyelids > forehead > cheeks. sWp in all areas except the eye corners was similar to the mean value in the cheeks in the group aged 18‐20 years. However, in the group aged 71‐83 years, marked differences were observed among the eye corners, glabella, mouth angles, nasolabial groove, and upper eyelids. Conclusion: Although sunlight is important in the development of three‐dimensional changes in surface morphology (wrinkles) in the face, other factors seem to play important roles for the progression of these changes.

It has been reported that the formation of wrinkles involves changes in the elastic properties of the dermis due to the denaturation of elastic fibers. Several studies have shown that the hydration condition of the stratum corneum is also important in wrinkle formation. It is, however, still unclear how the stratum corneum contributes to wrinkle formation. Here we investigated the relationship between the formation of wrinkles and changes in the physical properties and condition of the skin after repetitive ultraviolet B (UVB) irradiation of hairless mice (HR/ICR). Repetitive UVB irradiation caused wrinkles on the dorsal skin of the mice. The elasticity (E') of the stratum corneum of UVB-irradiated mice was significantly lower than that of age-matched control (unirradiated) mice. UVB exposure also caused a deterioration of the fibrous ultrastructure of keratin intermediate filaments (KIFs) in the skin. We conclude that the deterioration of KIFs in the stratum corneum caused by repetitive UVB irradiation decreases the elastic properties of the stratum corneum, resulting in the formation of wrinkles.