• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.637-643
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• 1995

TR75, a rice (Oryza sativa L. var. Sasanishikj) mutant resistant to 5-methyltryptophan (5MT) was segregated from the progenies of its initial mutant line, TR1. The 5MT resistance of TR75 was inherited in the M$_{8}$ generations as a single dominant nuclear gene, and was also expressed in callus derived from seeds, roots, and anthers as well as in the seedlings. The callus induced from these organs could grow at 50 mg/1 of 5MT, whereas the growth of wild-type callus was completely inhibited even at 25 mg/1. The seedlings of TR75 did not show resistance to L-azetidine-2-carboxylic acid, S-2-aminoethyl-L-cysteine, p-fluoro-DL-phenylalanine. The content of free amino acids in the TR75 homozygous seeds increased approximately 1.5 to 2.0 fold compared to wild-type seeds. Especially, the contents of tryptophan, phenylalanine and aspartic acid were 5.0, 5.3 and 2.7 times higher than those of wild-type seeds, respectively.y.

• The Journal of Internal Korean Medicine
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• v.38 no.6
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• pp.944-954
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• 2017

Objectives: This study investigated the anti-inflammatory effects of Jageum-jung extract on Dextran sulfate sodium (DSS-induced) ulcerative colitis in mice. Methods: Ulcerative colitis was induced by DSS in Balb/C male mice. Ten mice were assigned to each of four groups: Ctrl (control), UE (ulcerative colitis-induced), PT (treated with pentasaccharide after induction of ulcerative colitis), and JT (treated with Jageum-jung extract after induction of ulcerative colitis). The effects of Jageum-jung extract were measured by restoration of the length of the intestine, degree of mucosal damage as seen with histochemistry, and changes of p-IkB, iNOS, COX-2, and caspase-3 determined by immunohistochemistry. Results: The recovered intestinal length of the JT group was longer than that of the UE group. In the colon mucosa of JT group, hemorrhagic lesions were reduced, and the mucus barrier was recovered. This group also showed inhibited production of inflammatory enzymes (iNOS, COX-2) through regulation of proinflammatory enzyme (NF-kB, p65) activity in the colon. In addition, caspase 3 activation induced apoptosis. By GC/MS analysis, azetidine was identified. Conclusions: This study confirmed the anti-inflammatory effects of jageum-jung extract, and suggests the possibility of using Jageum-jung extract to treat ulcerative colitis. Further experiments and research on the mechanism of Jageum-jung effects are needed.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.3
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• pp.249-254
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• 2014

The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent.

• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.61-68
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• 2007

To develop rice (Oryza sativa L.) cultivars to be planted on salt-affected sites, cell lines with enhanced proline content and resistance to growth inhibition by Azetidine-2-carboxylic acid (AZCA), a proline analogue, were screened out among calli irradiated with gamma ray of 50, 70, 90, and 120 Gy. The calli had been derived from embryo culture of the cultivar Donganbyeo. Selected AZCA resistant lines that had high proline accumulation were used as sources for selection of NaCl resistant lines. To determine an optimum concentration for selection of NaCl resistant lines, Donganbyeo seeds were initially cultured on the media containing various NaCl concentrations (0 to 2.5%) for 40 days, and 1.5% NaCl concentration was determined as the optimum concentration. One hundred sixteen salt-tolerant (ST) lines were selected from bulked 20,000 seeds of the AZCA resistant $M_{3}$ seeds in the medium containing 1.5% NaCl. The putative 33 lines ($M_{4}$ generation) considered with salt-tolerance were further analyzed for salt tolerance, amino acid and ion contents, and expression patterns of the salt tolerance-related genes. Out of the 33 lines, 7 lines were confirmed to have superior salt tolerance. Based on growth comparison of the entries, the selected mutant lines exhibited greater shoot length with average 1.5 times, root length with 1.3 times, root numbers with 1.1 times, and fresh weight with 1.5 times than control. Proline contents were increased maximum 20%, 100% and 20% in the leaf, seed and callus, respectively, of the selected lines. Compared to control, amino acid contents of the mutants were 24 to 29%, 49 to 143%, 32 to 60% higher in the leaf, seed and callus, respectively. The ratio of $Na^{+}/K^{+}$ for most of the ST-lines were lower than that of control, ranging from 1.0 to 3.8 for the leaf and 11.5 to 28.5 for the root, while the control had 3.5 and 32.9 in the leaf and root, respectively. The transcription patterns for the P5CS and NHXI genes observed by RT-PCR analysis indicated that these genes were actively expressed under salt stress. The selected mutants will be useful for the development of rice cultivar resistant to salt stress.

• Biomedical Science Letters
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• v.9 no.2
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• pp.59-65
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• 2003

When cells are exposed to proteotoxic stresses such as heat shock, amino acid analogs, and heavy metals, they increase the synthesis of the heat shock proteins (HSPs) by activating the heat shock transcription factor 1 (HSF1), whose activity is controlled via multiple steps including homotrimerization, nuclear translocation, DNA binding, and hyperphosphorylation. Under unstressed conditions, the HSF1 activity is repressed through its constitutive phosphorylation by glycogen synthase kinase 3$\beta$ (GSK3$\beta$), extracellular regulated kinase 1/2 (ERK1/2), and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). However, the protein kinase (s) responsible for HSF1 hyperphosphorylation and activation is not yet identified. In the present study, we observed that profile of p38 mitogen-activated protein kinase (p38MAPK) activation in response to heat shock was very similar to those of HSF1 hyperphosphorylation and nuclear translocation. Therefore, we investigated whether p38MAPK is involved in the heat shock-induced HSF1 activation and HSP expression. Here we show that the p38MAPK inhibitors, SB202190 and SB203580, but not other inhibitors including the MEK1/2 inhibitor PD98059 and the PI3-K inhibitor LY294002 and wortmannin, suppress HSF1 hyperphosphorylation in response to heat shock and L-azetidine 2-carboxylic acid (Azc), but not to heavy metals. Furthermore, heat shock-induced HSF1-DNA binding and HSP72 expression was specifically prevented by the p38MAPK inhibitors, but not by the MEK1/2 inhibitor and the PI3-K inhibitors. These results suggest that SB202190- and SB203580-sensitive p38MAPK may positively regulate HSP gene regulation in response to heat shock and amino acid analogs.