OBP2A regulates epidermal barrier function and protects against cytotoxic small hydrophobic molecules.

The skin is constantly exposed to environmental sensory stimuli, which may include harmful volatiles and small hydrophobic molecules. However, the skin's protective mechanism against the latter agents is unclear. Here, we demonstrate that odorant binding protein 2A (OBP2A) protects epidermal keratinocytes against cytotoxic small hydrophobic molecules.

A mechanism of melanogenesis mediated by E-cadherin downregulation and its involvement in solar lentigines.

Objective: Intensive studies have revealed that pleiotropic melanocytic factors are associated with age-spot formation. Dysfunctional keratinocyte differentiation is thought to be an upstream cause of age-spot formation. Although it has been shown that keratinocyte differentiation is mediated by the cell-cell contact factor E-cadherin, its involvement in age-spot formation remains unknown.

Oral Supplementation of Collagen Peptides Improves Skin Hydration by Increasing the Natural Moisturizing Factor Content in the Stratum Corneum: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Introduction: We aimed to investigate the effect of orally ingested collagen peptides (CPs) on skin condition and elucidate their mechanism of action.

Methods: A randomized, placebo-controlled, double-blind trial was conducted in 99 healthy Japanese women, aged 35-50 years. The subjects were randomized into 3 groups (33 subjects/group) to receive 1 or 5 g of CP or placebo once daily for 12 weeks.

Influence of hydrophilic additives on the signal intensity in electrospray ionization of flavonoid glycosides.

Rationale: The influence of hydrophilic additives glycine, glucose, and glycerol on electrospray ionization (ESI) signal intensity of flavonoid glycosides and a nonreducing disaccharide is examined. The addition of excess glycine to the ESI solution would affect signal intensity more than glucose and glycerol due to its strong hydration capability.

Methods: The ESI signal response upon the addition of excess additives prepared was estimated in both selected ion monitoring and scan mode.

Influence of Solvent Composition and Surface Tension on the Signal Intensity of Amino Acids in Electrospray Ionization Mass Spectrometry.

The influence of solvent composition and surface tension on the signal intensity of deprotonated molecules [M-H] in electrospray ionization mass spectrometry (ESI MS) was evaluated using alanine (Ala), threonine (Thr) and phenylalanine (Phe), which have differing levels of hydrophobicity. The surface tension of the ESI solution was varied by changing the ratio of the organic solvents methanol (MeOH) and acetonitrile (MeCN) in water (HO). In ESI MS, the signal intensity of all the amino acids was increased with decreasing surface tension for the two solutions, HO/MeOH and HO/MeCN.

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).

Mass Spectrometry in Cosmetic Science: Advanced Ionization Techniques for Detecting Trace Molecules in or on Human Skin.

To provide safe and effective products to customers in the cosmetic industry, mass spectrometry (MS) is an indispensable analytical tool. In addition to its outstanding sensitivity and specificity, the method is applicable to a wide variety of compounds, which makes it irreplaceable for the development of cosmetics, which requires the analysis of complex systems. Because most cosmetic products are applied directly to the skin and function as they are designed, monitoring the molecular compositions of endogenous or exogenous compounds in or on the skin is crucial to ensure the safety and efficacy of a cosmetic product.

Zero volt paper spray ionization mass spectrometry for direct analysis of samples on filter paper substrate.

Rationale: Zero volt paper spray ionization (zvPSI) is a newly developed sample introduction/ionization technique for mass spectrometry (MS), which combines favorable features of paper spray ionization (PSI) and solvent-assisted inlet ionization (SAII). With a simple platform similar to PSI, zvPSI allows direct MS analysis of a broad type of samples (liquid, (semi-)solid, and imprint) without applying voltage.

Methods: In zvPSI-MS, a rectangular paper slip was used as a sample loader, extraction medium, and droplet emitter to introduce sample extract into the inlet of a mass spectrometer.

The corrected structure of depressoside, an antioxidative iridoid glucoside extracted from the flowers of Gentiana urnula Harry Sm.

Three known iridoid glucosides (gentiournoside A, gentiournoside E and depressoside) were isolated from the flowers of Gentiana urnula Harry Sm. through activity-guided fractionations with a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. All three compounds exhibited excellent DPPH radical scavenging activities (IC50: 10-20 μmol L(-1)) comparable to that of ascorbic acid and Trolox.

Mesotrypsin and caspase-14 participate in prosaposin processing: potential relevance to epidermal permeability barrier formation.

A proteomics-based search for molecules interacting with caspase-14 identified prosaposin and epidermal mesotrypsin as candidates. Prosaposin is a precursor of four sphingolipid activator proteins (saposins A-D) that are essential for lysosomal hydrolysis of sphingolipids. Thus, we hypothesized that caspase-14 and mesotrypsin participate in processing of prosaposin.

Kallikrein-related peptidase 5 functions in proteolytic processing of profilaggrin in cultured human keratinocytes.

Filaggrin protein is synthesized in the stratum granulosum of the skin and contributes to the formation of the human skin barrier. Profilaggrin is cleaved by proteolytic enzymes and converted to functional filaggrin, but its processing mechanism remains not fully elucidated. Kallikrein-related peptidase 5 (KLK5) is a major serine protease found in the skin, which is secreted from lamellar granules following its expression in the stratum granulosum and activated in the extracellular space of the stratum corneum.

DOCK7 is a critical regulator of the RAGE-Cdc42 signaling axis that induces formation of dendritic pseudopodia in human cancer cells.

Cellular migration is a fundamental process linked to cancer metastasis. Growing evidence indicates that the receptor for advanced glycation end products (RAGE) plays a pivotal role in this process. With regard to downstream signal transducers of RAGE, diaphanous-1 and activated small guanine nucleotide triphosphatases, Rac1 and Cdc42, have been identified.

S100A9 is a novel ligand of EMMPRIN that promotes melanoma metastasis.

The calcium-binding proteins S100A8 and S100A9 can dimerize to form calprotectin, the release of which during tissue damage has been implicated in inflammation and metastasis. However, receptor(s) mediating the physiologic and pathophysiologic effects of this damage-associated "danger signal" are uncertain. In this study, searching for candidate calprotectin receptors by affinity isolation-mass spectrometry, we identified the cell surface glycoprotein EMMPRIN/BASIGIN (CD147/BSG).

TIRAP, an adaptor protein for TLR2/4, transduces a signal from RAGE phosphorylated upon ligand binding.

The receptor for advanced glycation end products (RAGE) is thought to be involved in the pathogenesis of a broad range of inflammatory, degenerative and hyperproliferative diseases. It binds to diverse ligands and activates multiple intracellular signaling pathways. Despite these pivotal functions, molecular events just downstream of ligand-activated RAGE have been surprisingly unknown.

Changes of cell-surface thiols and intracellular signaling in human monocytic cell line THP-1 treated with diphenylcyclopropenone.

Changes of cell-surface thiols induced by chemical treatment may affect the conformations of membrane proteins and intracellular signaling mechanisms. In our previous study, we found that a non-toxic dose of diphenylcyclopropene (DPCP), which is a potent skin sensitizer, induced an increase of cell-surface thiols in cells of a human monocytic cell line, THP-1. Here, we examined the influence of DPCP on intracellular signaling.

Multidimensional LC separations in shotgun proteomics.

Two modes of separation coupled with MS enable researchers to study complicated biological structures.

Motif-specific sampling of phosphoproteomes.

Phosphoproteomics, the targeted study of a subfraction of the proteome which is modified by phosphorylation, has become an indispensable tool to study cell signaling dynamics. We described a methodology that linked phosphoproteome and proteome analysis based on Ba2+ binding properties of amino acids. This technology selected motif-specific phosphopeptides independent of the system under analysis.

Improving protein identification sensitivity by combining MS and MS/MS information for shotgun proteomics using LTQ-Orbitrap high mass accuracy data.

We investigated and compared three approaches for shotgun protein identification by combining MS and MS/MS information using LTQ-Orbitrap high mass accuracy data. In the first approach, we employed a unique mass identifier method where MS peaks matched to peptides predicted from proteins identified from an MS/MS database search are first subtracted before using the MS peaks as unique mass identifiers for protein identification. In the second method, we used an accurate mass and time tag method by building a potential mass and retention time database from previous MudPIT analyses.

A novel melanin inhibitor: hydroperoxy traxastane-type triterpene from flowers of Arnica montana.

We isolated a novel inhibitor of melanin biosynthesis from the flowers of Arnica montana L. (Compositae), and identified it as a traxastane-type triterpene (3beta,16beta-dihydroxy-21alpha-hydroperoxy-20(30)-taraxastene) [1] by means of 1D or 2D-NMR and liquid chromatography/high-resolution mass spectrometry (LC-HR-MS). Compound [1] at the concentration of 0.

Anion and cation mixed-bed ion exchange for enhanced multidimensional separations of peptides and phosphopeptides.

Shotgun proteomics typically uses multidimensional LC/MS/MS analysis of enzymatically digested proteins, where strong cation-exchange (SCX) and reversed-phase (RP) separations are coupled to increase the separation power and dynamic range of analysis. Here we report an on-line multidimensional LC method using an anion- and cation-exchange mixed bed for the first separation dimension. The mixed-bed ion-exchange resin improved peptide recovery over SCX resins alone and showed better orthogonality to RP separations in two-dimensional separations.

Automated ultra-high-pressure multidimensional protein identification technology (UHP-MudPIT) for improved peptide identification of proteomic samples.

Multidimensional separation is one of the most successful approaches for proteomics studies that deal with complex samples. We have developed an automated ultra-high-pressure multidimensional liquid chromatography system that operates up to approximately 20 kpsi to improve separations and increase protein coverage from limited amount of samples. The reversed-phase gradient is operated in the constant-flow mode opposed to the constant-pressure mode, which is typical of previous ultra-high-pressure systems.

Direct determination of endogenous melatonin in human saliva by column-switching semi-microcolumn liquid chromatography/mass spectrometry with on-line analyte enrichment.

An analytical method that enables direct and sensitive determination of endogenous melatonin (MLT) in human saliva was developed by means of column-switching semi-microcolumn liquid chromatography (i.d.: 1-2 mm)/mass spectrometry (LC/MS).

Direct determination of pindolol enantiomers in human serum by column-switching LC-MS/MS using a phenylcarbamate-beta-cyclodextrin chiral column.

A direct analytical method of pindolol enantiomers in body fluids was developed by means of column-switching semi-microcolumn liquid chromatography/tandem mass spectrometry (LC-MS/MS). A pre-column packed with a silica-based cation-exchanger was used for on-line sample cleanup. Subsequent enantioseparation was conducted with a phenylcarbamate-beta-cyclodextrin (ph-beta-CD) bonded semi-micro chiral column (2.