Key component of inflammasome, NLRC4, was identified in the lesional epidermis of psoriatic patients.

Inflammasomes are multimolecular complexes that control the inflammatory response. The function of inflammasomes in the pathogenesis of psoriasis is still unclear. To clarify the relationship between inflammasomes and the pathophysiology of psoriasis, and in particular, to identify molecules interacting with caspase-1, a crucial component of inflammasomes, scale extracts obtained from patients with psoriasis were immunoprecipitated with anti-caspase-1 antibody and analyzed by liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS).

Nuclear DNA damage-triggered NLRP3 inflammasome activation promotes UVB-induced inflammatory responses in human keratinocytes.

Ultraviolet (UV) radiation in sunlight can result in DNA damage and an inflammatory reaction of the skin commonly known as sunburn, which in turn can lead to cutaneous tissue disorders. However, little has been known about how UV-induced DNA damage mediates the release of inflammatory mediators from keratinocytes. Here, we show that UVB radiation intensity-dependently increases NLRP3 gene expression and IL-1β production in human keratinocytes.

Purification and characterization of active caspase-14 from human epidermis and development of the cleavage site-directed antibody.

Restricted expression of caspase-14 in differentiating keratinocytes suggests the involvement of caspase-14 in terminal differentiation. We purified active caspase-14 from human cornified cells with sequential chromatographic procedures. Specific activity increased 764-fold with a yield of 9.

Sagging of the cheek is related to skin elasticity, fat mass and mimetic muscle function.

Background/purpose: Facial sagging is associated with aging, although the mechanism remains unclear. The aim of this study was to investigate the mechanism of facial sagging by examining the relationship of sagging severity to changes of skin elasticity, fat mass and facial muscle function at the cheek.

Methods: Faces of 108 healthy Japanese female volunteers, aged 20-60 years were photographed at an angle of 45 degrees .

Functional characteristics of the skin surface of children approaching puberty: age and seasonal influences.

The aim of this study was to determine differences in the functional properties of the stratum corneum of children and adults, focusing on the influence of approaching puberty. Biophysical measurements were made of the stratum corneum of 32 healthy Japanese children aged 10-14 years and their mothers in summer and the following winter. The children showed significantly lower skin surface hydration.

Adiponectin and leptin up-regulate extracellular matrix production by dermal fibroblasts.

Adipocytes were recently shown to secrete adipocytokines, such as adiponectin and leptin, which may have an endocrine role. Subcutaneous adipose tissue lies just beneath the dermis, and dermal condition is correlated with body mass index (BMI). However, it is not clear whether adipocytokines released by adipocytes in subcutaneous adipose tissue influence the adjacent dermis.

In vivo evaluation of the protective capacity of sunscreen by monitoring urocanic acid isomer in the stratum corneum using Raman spectroscopy.

Background/purpose: Urocanic acid (UCA) is a major ultraviolet (UV) ray-absorbing component in the epidermis, and it isomerizes from the trans to the cis form upon exposure to UV radiation. Continuous measurement of UCA isomers in the skin at the same area is not available using conventional methods. This study aimed to evaluate the protective capacity of sunscreen by non-invasively monitoring the trans-UCA (t-UCA) amount in the stratum corneum (SC) by confocal Raman spectroscopy.

Protein carbonyls damage the water-holding capacity of the stratum corneum.

Background: Acrolein is a degradation product of lipid peroxide as well as a well-known environmental pollutant. As a hallmark of oxidatively damaged protein, protein carbonyl, including acrolein-protein adduct, has been observed in the skin. However, the influence of protein carbonylation on the stratum corneum (SC) has not yet been clarified.

Involvement of transglutaminase in ex vivo maturation of cornified envelopes in the stratum corneum.

The cornified envelope (CE) is a thin insoluble structure enveloping corneocytes, and is essential for the barrier function of the stratum corneum (SC). Our previous studies revealed that immature CEs are detected in the outermost layer of SC of barrier-impaired epidermis including the face and in various inflammatory disorders, using a non-invasive method to evaluate CE maturity. However, factors attributable for immaturity of CEs are still unclear.

Plasmin induces degradation and dysfunction of laminin 332 (laminin 5) and impaired assembly of basement membrane at the dermal-epidermal junction.

Background: The epidermal basement membrane (BM), located at the dermal-epidermal junction (DEJ), plays important roles not only in adhesion between epidermis and dermis, but also in controlling skin functions. In sun-exposed skin, the BM becomes disrupted and multilayered. In order to explore the impairment of BM assembly, we have used a skin-equivalent (SE) as a model of BM damage and previously clarified the involvement of matrix metalloproteinases (MMPs) in impairment of BM assembly.

Change in optical properties of stratum corneum induced by protein carbonylation in vitro.

The skin is the frontier against the external environment and continuously exposed to the environmental oxidative stress such as ultraviolet (UV) irradiation. Protein carbonyls are the major oxidative products of protein and may be introduced by reaction with aldehydes derived from lipid peroxide. Acrolein is one of the most reactive aldehydes generated during degradation of lipid peroxides and protein-acrolein adducts have been found in the oxidatively damaged lesion including UV-damaged skin.

Increased carbonyl protein levels in the stratum corneum of the face during winter.

The stratum corneum (SC) is the interface between the body and the environment, and is continuously exposed to oxidative stress that results in carbonyl modification of proteins. We previously developed a simple and non-invasive method to assess the stratum corneum carbonyl protein (SCCP) levels. In this study, we used this method to examine the seasonal changes in the SCCP levels and the relationship between the SCCP level and the physiological condition of the SC.

Fibulin-5 accelerates elastic fibre assembly in human skin fibroblasts.

Fibulin-5 null mice display abnormalities in the elastic fibres in the dermis. We postulated, therefore, that fibulin-5 might be a regulator of elastic fibre assembly and stability. To clarify the role of fibulin-5 in elastic fibre formation, we employed in vitro systems that allowed increasing expression of elastic fibre components by gene transduction using retroviral vector constructs.

Effects of fragrance administration on stress-induced prefrontal cortex activity and sebum secretion in the facial skin.

Although fragrances have long been known to influence stress-induced psychosomatic disorders, the neurophysiological mechanism remains unclear. We evaluated the effect of fragrance on the relation between the level of sebum secretion in the facial skin and the stress-induced prefrontal cortex (PFC) activity, which regulates the activity of the hypothalamic-pituitary-adrenal axis. Employing near infrared spectroscopy, we measured hemoglobin concentration changes in the bilateral PFC during a mental arithmetic task in normal adults (n=31), and evaluated asymmetry of the PFC activity in terms of the laterality index (i.

Comparison of the depth profiles of water and water-binding substances in the stratum corneum determined in vivo by Raman spectroscopy between the cheek and volar forearm skin: effects of age, seasonal changes and artificial forced hydration.

Background: Dermatologists and cosmetic scientists are becoming increasingly interested in stratum corneum (SC) hydration because the SC plays an important role in keeping the skin surface soft and smooth. However, conventional in vivo noninvasive methods do not provide direct information about the depth profiles of water content or SC components that hold water.

Objectives: To study the depth profiles of water and SC components in vivo by Raman spectroscopy, and to analyse the changes due to age, anatomical location, season and water application.

Relation between mental stress-induced prefrontal cortex activity and skin conditions: a near-infrared spectroscopy study.

Although psychological stress affects skin condition, the neurophysiological mechanism involved is unclear. In this study, we evaluated the relationship between skin condition and left/right asymmetry in prefrontal cortex (PFC) activity during mental stress tasks since recent studies have suggested that the right PFC dominates the regulation of the stress response system, including the hypothalamic-pituitary-adrenal (HPA) axis. Using near-infrared spectroscopy, we measured hemoglobin concentration changes in the bilateral PFC during a mental arithmetic task in normal adults and evaluated the laterality scores (i.

Establishment of a mouse skin model of the lichenification in human chronic eczematous dermatitis.

Background: Repeated mechanical stresses, such as scratching and rubbing, on a lesional skin area induce a rough skin condition known as lichenification in patients with chronic eczematous dermatitis. For ethical reasons, the pathomechanisms involved are difficult to study, so an animal model is required.

Objectives: To study the pathomechanisms of the unique rough skin changes seen in chronic eczematous dermatitis, we established a mouse skin model by repeated tape stripping to inflict stratum corneum (SC) barrier disruption.

Epidermal keratinocytes as the forefront of the sensory system.

Various sensors that respond to physical or chemical environmental factors have been identified in the peripheral nervous system. Some of them, which respond to mechanical stress, osmotic pressure, temperature and chemical stimuli (such as pH), are also expressed in epidermal keratinocytes. Neurotransmitters and their receptors, as well as receptors that regulate the neuroendocrine system of the skin, are also present in keratinocytes.

A simple and non-invasive visualization for assessment of carbonylated protein in the stratum corneum.

Background/purpose: Stratum corneum (SC) is the interface of body and environment and is continuously exposed to oxidative stress, resulting in oxidative modification of proteins. Consequent carbonylated proteins (CPs) have so far been labeled with 2,4-dinitrophenyl (DNP) hydrazine and subsequently detected with anti-DNP antibody. We developed a simpler, non-invasive method to assess CP level in the SC and applied it to following research.

Quantitative analysis of the synthesis and secretion of type VII collagen in cultured human dermal fibroblasts with a sensitive sandwich enzyme-linked immunoassay.

Type VII collagen is the major component of anchoring fibrils in the epidermal basement membrane. Its expression has been analyzed by immunostaining or Northern blotting, but rarely at the protein level. In this study, we have quantitatively examined the effects of ascorbic acid and various cytokines/growth factors on the protein synthesis and secretion of type VII collagen by human dermal fibroblasts in culture, using a developed, highly sensitive sandwich enzyme-linked immunoassay with two kinds of specific monoclonal antibodies against the non-collagenous domain-1.

c-JUN N-terminal kinase-1 (JNK1) but not JNK2 or JNK3 is involved in UV signal transduction in human epidermis.

Background: c-Jun N-terminal kinase (JNK) plays a critical role in UV-induced apoptotic cell death. Although three isoforms are known in mammals, physiological roles of each isoform are still obscure. Furthermore, our recent findings show that serpin squamous cell carcinoma antigen (SCCA1) binds to JNK.

Serpin squamous cell carcinoma antigen inhibits UV-induced apoptosis via suppression of c-JUN NH2-terminal kinase.

Protection from ultraviolet (UV) irradiation is a fundamental issue for living organisms. Although melanin's critical role in the protection of basal keratinocytes is well understood, other factors remain essentially unknown. We demonstrate that up-regulation of squamous cell carcinoma antigen-1 (SCCA1) suppresses c-Jun NH2-terminal kinase-1 (JNK1) and thus blocks UV-induced keratinocyte apoptosis.

Carbonylation of cornified envelopes in the stratum corneum.

Stratum corneum (SC), the outermost layer of the skin, is continuously exposed to oxidative stress via sunlight, lipid peroxidation, and is subsequently accompanied by oxidative modification. Previous studies have shown that major oxidative target proteins in the SC are keratins. However, it remains unclear to date whether cornified envelopes (CEs), protein envelopes of the corneocytes (cornified cells), would be oxidized.

Expression profiling and cellular localization of genes associated with the hair cycle induced by wax depilation.

The hair cycle is a highly regulated process controlled by multiple factors. Systematic analysis of gene expression patterns in each stage of the hair cycle would provide information useful for understanding this complicated process. To identify genes associated with the hair cycle, we used DNA microarray hybridization to analyze sequential gene expression patterns in mouse skin following hair cycle synchronization by wax depilation.

Hair cycle-specific expression of versican in human hair follicles.

Background: Versican, a large chondroitin sulfate proteoglycan molecule, is implicated in the induction of hair morphogenesis, the initiation of hair regeneration, and the maintenance of hair growth in mouse species. In contrast, in human hair follicles, the distribution and the roles of versican remains obscure.

Objectives: To elucidate the implication of versican in normal human hair growth.