Recently, the values, consciousness, and behaviors regarding men’s beauty have been changing. Similarly, most research with skin measurements in the past have only been performed on women and many of the characteristics specific to men’s skin remain to be elucidated. In this study, we conducted a human test on healthy Japanese men and women, aged between 25 and 40 in summer. Our data suggested that men’s skin in the cheek compared to women’s showed the following characteristics: lower water content, higher trans-epidermal water loss, lower Ua/Uf value, which shows the skin’s recovery rate, and lower Ur/Uf value, which shows skin elasticity when shrinking. Also, skin brightness (L*) was significantly lower, and redness (a*) and yellowness (b*) were significantly higher in men, suggesting that men have darker, redder, and yellower skin. To find out the causes of these differences, we measured the amount of superoxide dismutase 1 in the stratum corneum (SC) in the cheek and newly discovered that the amount in men was less than half of that in women. Furthermore, the ratio of interleukin-1 receptor antagonist/interleukin-1 alpha, an indicator of chronic inflammation in the SC, was significantly higher in men. From our study, it was suggested that the cause behind this was not just the less frequent use of skincare and sun care. For damage caused by environmental stress in summer, it appears men’s skin has a lower anti-oxidant ability after damage is sustained.

Background: Secreted protein acidic and rich in cysteine (SPARC) regulates extracellular matrix (ECM) production, interaction of cells with ECM and growth factor-dependent cell signaling. Here we examined SPARC’s effects on production and pericellular organization of type I collagen and hyaluronan (HA) in normal human dermal fibroblasts.

Methods: Production of procollagen I and HA, and gene expression were analyzed by ELISA and quantitative real-time PCR, respectively. The pericellular deposition of mature collagen I and HA was examined by immunocytochemistry.

Results: SPARC enhanced production of procollagen I and HA in fibroblasts by up-regulating mRNA expression of COL1A1 (collagen α-1(I)) and HAS (HA synthase) 2/3, respectively. SPARC also increased the deposition of mature collagen fibrils on the cell surface of fibroblasts, accompanying the increased mRNA expression of procollagen C-proteinase (BMP1) and N-proteinase (ADAMTS2). The pericellular deposition of newly produced HA was also enhanced on the cell surface of SPARC-treated fibroblasts. Furthermore, SPARC up-regulated TGF-β1 production in fibroblasts, and SPARC-induced procollagen I and HA production was abolished by blockade of TGF-β/Smad2/3 signaling.

Conclusion: SPARC simultaneously up-regulates production of procollagen I and HA in fibroblasts by up-regulating Smad2/3-dependent TGF-β signaling, and also promotes the pericellular organization of mature collagen I fibrils and HA.

Recently, there are many sensitive skin persons in the world. From the viewpoint of the severity of skin symptoms, sensitive skin is between healthy skin and diseased skin. On the other hand, sensitive skin is classified as dry sensitive skin, oily sensitive skin and hypersensitive skin from skin physiological characteristics. Dry sensitive skin is characterized as low skin barrier, low secreted sebum and hypersensitivity. Oily sensitive skin is characterized as low skin barrier, high secreted sebum and hypersensitivity. There is another sensitive skin type whose skin barrier is normal but the skin is hypersensitive. This type is classified as hypersensitive skin.

Ceramides have important role of skin barrier function. The skin barrier function depends on the amount and on the profile of ceramides in the stratum corneum. The decrease in amounts of ceramides and changes in the profile of ceramides in the stratum corneum cause sensitive skin symptoms.

Thus, skin cleansing with keeping skin ceramides and topical treatment of ceramides are important for sensitive skin with low barrier function. Ceramides are often decreased while skin cleansing with traditional alkalic soaps. In a clinical test, dry sensitive skin was significantly improved by our mild acidic hand wash which can keep skin ceramides while washing. Replenishing ceramides or a pseudo-ceramide to low barrier skin is considered as crucial skin care. The pseudo-ceramide was designed and synthesized for a moisturizing ingredient. There are many reports that dry sensitive skin became hydrated and the skin barrier was improved by topical treatment of the pseudo-ceramide. In addition, improvement of skin symptoms of oily sensitive skin by a combination use with a mild acidic face wash and skin moisturizers with the pseudo-ceramide has demonstrated in a clinical test.

The stratum corneum, the outermost layer of the skin, retains water and functions as a chemical and physical barrier against external stimuli. The upper layer of normal stratum corneum has a basket-weave structure, and the gaps between the cells of this skin layer are filled with intercellular lipids. We focused on this basket-weave structure and examined its role in the function and condition of the stratum corneum. Results indicated that the basket-weave structure is important for improving the barrier function and flexibility of the stratum corneum. Investigation of skin care formulations that promote the formation of the basket-weave stratum corneum revealed oil-in-water emulsion A as a formulation that not only promotes the formation of the basket-weave stratum corneum, but also enhances the barrier function and flexibility of this essential skin layer.

The surface of the skin is covered by a stratified epithelium, the surface of which is cornified. After leaving the basal layer, epidermal keratinocytes differentiate and move upward, forming a tight junction barrier in the second layer of stratum granulosum, then move outside the tight junction barrier and become cornified. The terminal differentiation of keratinocytes, i.e. cornification and lipid lamellae formation between keratinocytes, occurs at the outside tight junction barrier. While each cell undergoes its own series of differentiation processes, the structure and barrier function of the entire epidermis is always maintained in a steady state. The key mechanisms maintaining the homeostasis of the tight junction barrier are the shape of keratinocytes in granular layer, Kelvin’s tetrakaidecahedron, and the relocation of tight junctions from one edge to another edge on the tetrakaidecahedron cells. The spatiotemporal orchestration of the upward movement of tetrakaidecahedron cells and downward relocation of tight junctions maintain the tight junction barrier at the second layer of stratum granulosum during continuous cell turnover.

Most infants with atopic dermatitis are sensitized with any food allergen even when they have not yet taken the offensive food. Although trace amounts of food allergens combined with IgG could be transmitted through umbilical cord from a pregnant mother and very small amount of food allergens could be detected in the breast milk of a mother who took the offensive foods, those allergens could not induce their sensitization to the infants of the mother. Allergen specific IgE concentrations are associated with severity of eczema and the amounts of the allergens detected in the house dust of bed sheets and the living room. Major route of food allergen sensitization is believed to inflamed skin. Infantile onset eczema/atopic dermatitis is the strongest risk factor of food allergy and especially infant onset persistent type of atopic dermatitis was reportedly a risk factor of asthma and allergic rhinitis. Atopic march will be implemented from skin sensitization.