Publications by authors named "Gae-Won Nam"

Inhibition of matrix metalloproteinases (MMPs), which degrade collagen and elastin in the dermis of normal skin, is a key strategy for anti-skin aging. In this study, we identified five low-molecular-weight (LMW, <1 kDa) MMP-1-suppressive peptides in feather keratin hydrolysate (FKH) obtained by anaerobic digestion with an extremophilic bacterium. FKH was first subjected to ultrafiltration, followed by size-exclusion chromatography and liquid chromatography/electrospray ionization tandem mass spectrometry analysis.

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Poultry feathers consist mainly of the protein keratin, which is rich in β-pleated sheets and consequently resistant to proteolysis. Although many keratinases have been identified, the reasons for their substrate specificity towards β-keratin remain unclear due to difficulties in preparing a soluble feather keratin substrate for use in activity assays. In the present study, we overexpressed Gallus gallus chromosomes 2 and 27 β-keratin-encoding genes in Escherichia coli, purified denatured recombinant proteins by Ni2+ affinity chromatography, and refolded by stepwise dialysis to yield soluble keratins.

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A rapid, sensitive and specific hydrophilic interaction liquid chromatography coupled to tandem mass spectrometric (HILIC-MS/MS) method for the simultaneous determination of pyroglutamic acid, cis- and trans-urocanic acid in human skin stratum corneum (SC) were developed and validated. This method was carried out without derivatization or addition of ion-pair additives in mobile phase. The analytes were extracted by PBS buffer solution and analyzed using an electrospray positive ionization mass spectrometry in the multiple reaction monitoring (MRM) mode.

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Background/purpose: The purpose of this study is to investigate the optimum combination of polyols and oils in moisturizing cosmetic products to improve the human skin moisturization and skin surface roughness. Polyols and oils are essential ingredients in skin care products, but it is still not understood how their concentrations affect their efficacy and sensory properties on human skin. We investigated the effect of polyol and oil concentration on skin properties by noninvasive methods.

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Peroxisome proliferators activated receptors (PPARs) are a family of nuclear hormone receptors that heterodimer with the retinoid X receptor and function as transcriptional regulators of genes. Topically Applied PPAR-alpha agonists possess receptor mediated, pro-differentiating/anti-proliferative effects, lipid metabolism stimulation, and anti-inflammatory activity, which suggest that they could be beneficial for the treatment of a variety of cutaneous diseases. Hyaluronan (HA), a high-molecular-weight linear glycosaminoglycan consisting of alternating D: -glucuronic acid and N-acetyl-D: -glucosamine residues, is one of the major extracellular matrix components in skin.

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Naturally occurring triterpenoids such as oleanolic acid (OA) and ursolic acid (UA) are known to have anti-inflammatory and anticarcinogenic activities in some types of cells. Although it has been reported that UA increases the amount of ceramide in keratinocytes, there is little study on the mechanism of triterpenoids involved in the differentiation of keratinocytes as well as their effects on epidermal permeability barrier. A study was therefore conducted to determine whether OA and UA could stimulate the differentiation of epidermal keratinocytes through peroxisome proliferator-activated receptor (PPAR)-alpha activation.

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The methanolic extract of the fruits of Torilis japonica showed a potent inhibition against 5 alpha-reductase activity in vitro. Bioassay-guided fractionation of the methanol extract of the fruits followed by repeated silica gel chromatography led to the isolation of an active principle and its structure was identified as torilin on the basis of spectroscopic data. Torilin (IC50 = 31.

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A native-feather-degrading thermophilic anaerobe was isolated from a geothermal hot stream in Indonesia. Isolate AW-1, identified as a member of the species Fervidobacterium islandicum, was shown to degrade native feathers (0.8%, w/v) completely at 70 degrees C and pH 7 with a maximum specific growth rate (0.

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