• Journal of the Korean Chemical Society
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• v.43 no.5
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• pp.540-546
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• 1999

Solution conformation of cyclo-($Gln^1-Trp^2-Phe^3-{\beta}Ala^4-Leu^5-Met^6$), new NK-2 antagonist in dimethyl sulfoxide solution, has been determined by the use of two-dimensional nuclear magnetic resonance spectroscopy combined with simulated annealing calculations. The peptide exhibited converged structures with the atomic root-mean-square difference for the backbone atoms ($N,\;C^{\alpha},\;C'$) of all residues being 0.02${\AA}$ in the 25 annealed structures. The analysis of the structures indicated that the cyclic peptide has three intramolecular hydrogen bonds between $Met^6NH$ and ${\beta}Ala^4CO$, ${\beta}Ala^4NH$ and $Met^6CO$, $Phe^3NH$ and $Met^6CO$, and contain a type-I ${\beta}$-turn with Gln and Trp and ${\gamma}$-turn with Leu. The addition of an extra methylene group to Gly, i.e. P-Ala residue, may relax some unfavorable restraints in the cyclic backbone structure, hence enabling an additional hydrogen bond, which results in stabilizing one conformation.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.89-93
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• 2020

In this study, the efficacy of melanoma cell B16F10 was investigated using the Korean native plant Oplismenus undulatifolius (OU). First, the cell viability of the extract was more than 90% when treated with 15 ㎍/mL of phenolics from OU. The results showed that melanin biosynthesis and cellular tyrosinase synthesis were inhibited by treatment with α-melanocyte-stimulating hormone-stimulated mouse melanoma cell B16F10 at a concentration of 15 ㎍/mL of phenolics for cell-line efficacy. The expression of tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2, and microphthalmia transcription factor (MITF) protein was confirmed by western blot to investigate the effect of phenolics from OU on melanin biosynthesis. When treated with phenolics from OU 15 ㎍/mL, tyrosinase, TRP-1, TRP-2, and MITF decreased the protein expression level. In particular, tyrosinase, TRP-1, and MITF inhibited the production amount to a level similar to that of the non-treated normal group, indicating that the effect was excellent. Therefore, phenolics from OU acts as an inhibitor of tyrosinase, TRP-1, TRP-2, and its transcription factor MITF, and participates in melanin biosynthesis mechanism. These results suggested the potential for development as a material.

• Journal of Food Hygiene and Safety
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• v.7 no.4
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• pp.161-168
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• 1992

On the mutagenicity induced by 3-amino-l,4-dimethyl-5-H-pyrido[4,3-b]indol (Trp-P-1) and 2-aminotluorene (2-AF), the antimutagenic effects of edible muntain herb juices were examined by the Ames assay using Salmonella typhimurium TA98 and TA100. Juices prepared from aralia bud, small water dropwort, mugwort, roots of belltlower and sedum didn't have mutagenicity. Most of sample juices showed the antimutagenicity. Especially, juices prepared from aralia bud, small water dropwort and mugwort were found to possess strong antimutagenic effects. Sedum was moderatly effective and root of belltlower had little effect on mutagenicity caused by Trp-P1 and 2-AF. The experimental results with TA98 were similar to those with TA100 in the antimutagenicity test of edible mountain herb juices. In this study, antimutagenicity on Trp-P-1 was more effective than that on 2-AF.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1456-1461
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• 2007

Melanogenesis is induced mainly by ultraviolet radiation of sunlight and ${\alpha}-melanocyte$-stimulating hormone (${\alpha}-MSH$) which binds to a specific G protein coupled receptor. The purpose of this study was to investigate the mechanism of melanogenesis inhibition in B16/F10 cells by methanol extract of Rubus coreanus Miquel (RCM). In the present study, ${\alpha}-MSH$ and forskolin led to a stimulation of melanin synthesis that appeared to result from an increased tyrosinase activity and melanin content. However, RCM inhibited the ${\alpha}-MSH$- and forskolin-induced melanin synthesis. In addition, RCM abolished the ${\alpha}-MSH$- and forskolin-induced cytoplasmic dendricity. Regarding protein levels of the melanogenic enzymes, the amounts of tyrosinase and tyrosinase-related protein 1 (TRP-1) were increased after incubation with α-MSH and forskolin. The treatment of RCM decreased the ${\alpha}-MSH$- and forskolin-induced expression levels of tyrosinase and TRP-1. Based on these findings, it is likely that RCM exerts its depigmenting effects in B16/F10 cells through the suppression of tyrosinase and TRP-1 expression, which are key enzymes for melanogenesis.

• KSBB Journal
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• v.10 no.1
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• pp.38-45
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• 1995

The expression of Aspergillus nidulans glyceraldehyde-3-phosphate dehydrogenase (gpdA) and trpC promoters in A. oryzae were compared using E. coli lacZ gents fusions. The specific activities of the expressed E. coli $\beta$-galactosidase in A. oryzae transformants containing the A. nidulans gpdA promoter were around 2,000 units per ug of protein. The specific activities of transformants containing the A. nidulans trpC promoter were very low, ranging from 10.5 to 52.3 units per ug of protein. These results showed that the expression of the A. nidulans gpdA promoter in A. oryzae was approximately 70 times greater than the A. nidulans trpC promoter. In western blot analysis, immunoreactive bands of a imlilar molecular weight as the E. coli $\beta$-galactosidase were observed in A. oryzae carrying the gpdA-lacZ fusion and to a lesser intensity in those carrying the tvpC-lacZ fusion. Southern analysis showed that the higher expression of the gpdA-lacZ fusion as compared to the trpC-lacZ fusion was not due a greater number of integrated plasmids.

• Journal of Life Science
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• v.29 no.3
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• pp.279-286
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• 2019

This study evaluated the anti-oxidant and whitening effects of a 70% ethanol extract of the Sambucus sieboldiana var. pendula (Nakai) (SS). At $1,000{\mu}g/ml$ concentration, the electron donating ability of this SS extract was found to be 86.21% and the ABTS+ radical scavenging ability was 97.9%. In terms of whitening activity, the tyrosinase inhibitory effect of the extract was 37%, also at $1,000{\mu}g/ml$ concentration. To explore the extractefftoxicity to B16F10 melanoma cells, a 3-[4,5-dimethyl-thiazol-2-yl]-2,5-diphenyl-tetrazoliumbromide assay was performed. Results showed 90% or more cells remained viable at $100{\mu}g/ml$ concentration. A Western blot of the SS extract was used to measure microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TRP-1), tyrosinase relate protein-2 (TRP-2), and the tyrosinase protein expression inhibitory effect at 25, 50, $100{\mu}g/ml$ concentrations; ${\beta}-actin$ was used as a positive control. Consequently, the MITF, TRP-1, TRP-2, and the tyrosinase protein expression inhibitory effect were seen to decrease by 34.5%, 45.6%, 58.4%, and 79.6%, respectively, at $100{\mu}g/ml$ concentration. These were also then measured by reverse transcription-polymerase chain reaction at 25, 50, $100{\mu}g/ml$ concentrations with GAPDH as a positive control. As a result, the SS extract was seen to decrease MITF, TRP-1, TRP-2, and the tyrosinase protein expression inhibitory effect by 85.4%, 67.5%, 85.2%, 67.1%, respectively at the $100{\mu}g/ml$ concentration. We therefore confirmed the possibility of Sambucus sieboldiana var. pendula (Nakai) extract as a whitening material.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5637-5642
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• 2012

Objective: Gastric cancer (GC) is one of the most common malignancies and its mortality ranks third among all cancers in China. We previously noted that XRCC1 Arg194Trp was associated with GC risk in Western China in a study on XRCC1 Arg194Trp and ADPRT Val762Ala. We aimed to further explore the association of these polymorphisms with risk of the noncardia subtype. Methods: We enrolled 176 noncardia GC patients and 308 controls from four hospitals and a community between October 2010 and August 2011. Genotyping was performed in a 384-well plate format on the Sequenom MassARRAY platform. A self-designed questionnaire was utilized to collect epidemiological data from the subjects regarding demographic factors and potential risk factors. Results: Subjects were aged $56.8{\pm}11.8$ (mean ${\pm}$ standard deviation) and $57.6{\pm}11.1$ years in the case and control groups, respectively. Individuals carrying the XRCC1 Trp/Trp or Arg/Trp variant genotype were at significantly increased risk of noncardia GC (adjusted OR, 1.48; 95% CI, 1.00-2.17), after adjustment for family history of cancer, drinking, and smoking. The increased risk of XRCC1 Arg194Trp variant genotype was more pronounced among subjects below 60 years old (adjusted OR, 1.78; 95% CI, 1.07-2.96), compared to older individuals. ADPRT Val762Ala variants (Ala/Ala or Val/Ala) were not associated with noncardia GC (adjusted OR, 1.03; 95% CI, 0.69-1.54). Conclusions: Our study suggests that XRCC1 Arg194Trp is a genetic susceptibility factor for developing noncardia GC in Han Chinese in Western China. In particular, individuals with the XRCC1 Arg194Trp variant genotype are at increased risk for GC below 60 years old.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2139-2144
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• 2012

Objective: Gastric cancer remains a major health problem in China. We hypothesized that XRCC1 Arg194Trp and ADPRT Val762Ala may be associated with risk. Methods: We designed a multicenter 1:1 matched case-control study of 307 pairs of gastric cancers and controls between October 2010 and August 2011. XRCC1 Arg194Trp and ADPRT Val762Ala were sequenced, and demographic data as well as lifestyle factors were collected using a self-designed questionnaire. Results: Individuals carrying XRCC1 Trp/Trp or Arg/Trp variant genotype had a significantly increased risk of gastric cancer (OR, 1.718; 95% CI, 1.190-2.479), while the OR for ADPRT Val762Ala variant genotype (Ala/Ala or Val/Ala) was 1.175 (95% CI, 0.796-1.737). No gene-gene or gene-environment interactions were found. In addition, family history of cancer and drinkers proportion were higher among cases than among controls (P<0.05). Conclusions: XRCC1 194 Arg/Trp or Trp/Trp genotype, family history of cancer, and drinking are suspected risk factors of gastric cancer from our study. Our findings may offer insight into further similar large gene-environment and gene-gene studies in this region.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.451-460
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• 2015

An enantioselective recognition of D- and L-tryptophan (Trp)-b-cyclodextrin (CD) inclusion complex was performed using electrochemical and FT-Raman spectroscopic analysis. From the electrochemical analysis, the selectivity coefficient ($K_{DL}$) of b-CD inclusion complexes was found higher than that of the D- and L-Trp in phosphate buffered saline (PBS, pH=7.0) solution. The percentage of enantioselectivity ($I_{%{ee}}$) for peak current of D-Trp-b-CD inclusion complexes was observed higher than that of L-Trp-b-CD inclusion complexes in PBS solution. From Raman spectroscopy, chemical shift difference (D, $cm^{-1}$) for the C=C stretch, ring vibration, and ring breathing of D-Try-b-CD inclusion complex were observed higher than that of L-Trp-b-CD inclusion complex. The electrochemical and Raman spectroscopic analyses were found very useful for chiral detection of racemic amino acid in the presence of b-CD.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.6
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• pp.432-438
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• 2016

This study was peformed to investigate the mechanism of ethanol extract of Eclipta Prostrata (L.) L. (EEP) induced melanogenesis. EEP enhanced tyrosinase activity and melanin contents of B16F10 cells. Moreover, EEP increased the protein expression of tyrosinase and tyrosinase-related protein 1 (TRP-1). But EEP did not increase the protein expression of tyrosinase-related protein 2 (TRP-2). These results suggest that melanogenesis-promoting effect of EEP was involved in regulation of tyrosinaase and TRP-1 protein, and EEP may be a potent pigmentation darkening agent in hypopigmentation condition.