• Preventive Nutrition and Food Science
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• 제17권2호
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• pp.109-115
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• 2012

This study was designed to investigate the inhibitory effects of Perilla frutescens (L.) Britton var. frutescens extract on the production of inflammation-related mediators (NO, ROS, NF-${\kappa}B$, iNOS and COX-2) and pro-inflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$, IL-6) in lipopolysaccharide-stimulated RAW 264.7 macrophages. Perilla frutescents (L.) Britton var. frutescens was air-dried and extracted with ethanol. The extract dose-dependently decreased the generation of intracellular reactive oxygen species and dose-dependently increased antioxidant enzyme activities, such as superoxide dismutase, catalase and glutathione peroxidase in lipopolysaccharide stimulated RAW 264.7 macrophages. Also, Perilla frutescens (L.) Britton var. frutescens extract suppressed NO production in lipopolysaccharide-stimulated RAW 264.7 cells. The expressions of pro-inflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$ and IL-6), NF-${\kappa}B$, iNOS and COX-2 were inhibited by the treatment with the extract. Thus, this study shows the Perilla frutescens (L.) Britton var. frutescens extract could be useful for inhibition of the inflammatory process.

• 미생물학회지
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• 제34권4호
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• pp.243-247
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• 1998

Allomyces macrogynus를 대상으로 꼬리홀씨와 팡이실에서 tetrahydrobiopterin의 세포내 농도와 그 생합성 효소들의 활성을 비교분석하였다. 습윤중량의 세포를 기준으로 비교하였을 때 biopterin은 홀씨에 비해 팡이실에서 14배 정도 많은 양이 검출되었다. 그 생합성에 관여하는 GTP cyclohydrolase I(GTPCH), 6-pyruboyltetrahydropterin synthase(PTPS), sepiapterin reductase(SR)의 효소활성을 ammonium sulfate 단백질 농축액에서 분석한 결과 GTPCH와 PTPS의 활성은 팡이실에서 꼬리홀씨에 비해 약 2배 정도 높은 값을 보여주었다. 반면 SR의 활성은 오히려 꼬리홀씨에서 10배 정도 높은 것으로 분석되었다. 그리고 Northern blot 분석 결과 SR의 전사물도 꼬리홀씨에서 훨씬 많이 검출되었다. 이러한 결과들은 tetrahydrobiopterin이 Allomyces macrogynus의 팡이실 분화단계에 관여하고 있음을 추정케하는 한편 SR의 생리활성과 관련된 의문을 제기하고 있다.

• The Korean Journal of Physiology and Pharmacology
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• 제23권6호
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• pp.519-528
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• 2019

Mitochondrial dysfunction is closely associated with reactive oxygen species (ROS) generation and oxidative stress in cells. On the other hand, modulation of the cellular antioxidant defense system by changes in the mitochondrial DNA (mtDNA) content is largely unknown. To determine the relationship between the cellular mtDNA content and defense system against oxidative stress, this study examined a set of myoblasts containing a depleted or reverted mtDNA content. A change in the cellular mtDNA content modulated the expression of antioxidant enzymes in myoblasts. In particular, the expression and activity of glutathione peroxidase (GPx) and catalase were inversely correlated with the mtDNA content in myoblasts. The depletion of mtDNA decreased both the reduced glutathione (GSH) and oxidized glutathione (GSSG) slightly, whereas the cellular redox status, as assessed by the GSH/GSSG ratio, was similar to that of the control. Interestingly, the steady-state level of the intracellular ROS, which depends on the reciprocal actions between ROS generation and detoxification, was reduced significantly and the lethality induced by $H_2O_2$ was alleviated by mtDNA depletion in myoblasts. Therefore, these results suggest that the ROS homeostasis and antioxidant enzymes are modulated by the cellular mtDNA content and that the increased expression and activity of GPx and catalase through the depletion of mtDNA are closely associated with an alleviation of the oxidative stress in myoblasts.

• Archives of Pharmacal Research
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• 제23권3호
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• pp.246-251
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• 2000

In most tissues, apoptosis plays a pivotal role in normal development and for regulating cell number, thus inappropriate apoptosis underlies a variety of diseases. Caspase-3 is one of a family of caspases that are mainly involved in the apoptotic signal transduction pathway, where caspase-3 acts as an effect molecule to proteolytically cleave intracellular substrates that are necessary for maintaining cell survival. Recent evidences show that apoptotic cell death can be blocked by inhibiting caspase-3, suggesting its inhibitors have potential to be therapeutic drugs for the diseases related with inappropriate apoptosis. We have established a screening system to search caspase-3 inhibitors from chemical libraries stocked in our institute. The enzyme assay is configured entirely in 96-well format, which is easily adapted for high throughput screening. Before performing mass screening, 80 in-house compounds were screened as a preliminary experiment, and we found that morin hydrate inhibited caspase-3 by 66.4 % at the final concentration of 20 ${\mu}g/m{\ell}$.

• Molecules and Cells
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• 제44권5호
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• pp.318-327
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• 2021

CD4+ T helper (Th) cells play a crucial role in the modulation of innate and adaptive immune responses through the differentiation of Th precursor cells into several subsets, including Th1, Th2, Th17, and regulatory T (Treg) cells. Effector Th and Treg cells are distinguished by the production of signature cytokines and are important for eliminating intracellular and extracellular pathogens and maintaining immune homeostasis. Stimulation of naive Th cells by T cell receptor and specific cytokines activates master transcription factors and induces lineage specification during the differentiation of Th cells. The master transcription factors directly activate the transcription of signature cytokine genes and also undergo post-translational modifications to fine-tune cytokine production and maintain immune balance through cross-regulation with each other. This review highlights the post-translational modifications of master transcription factors that control the differentiation of effector Th and Treg cells and provides additional insights on the immune regulation mediated by protein argininemodifying enzymes in effector Th cells.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.569-573
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• 2020

Brucellosis is a zoonotic disease caused by Brucella infections and humans usually contract this disease from close contact with infected animals or their products, usually via the ingestion of cheese or crude milk. Macrophage migration inhibitory factor (MIF) and Pro- and anti-inflammatory cytokines play an important role in susceptibility/resistance and the immunopathogenesis of Brucella infection. These cytokines are crucial factors in the initiation and progression of protective immunity against Brucella infection but the role of MIF has not been well studied in the human response to intracellular microbes. This study was designed to investigate the effect of MIF expression on Brucella susceptibility. A total of 85 positive rose Bengal tests and 24 samples from healthy individuals were collected for this study and subjected to polymerase chain reaction assays (PCR) of the bcsp31 diagnostic gene. MIF concentrations were evaluated using Enzyme-Linked immunosorbent assay (ELISA) and the results showed that 46 (54%) of the rose Bengal test samples were positive and 39 (46%) were negative for bcsp31 (p ≤ 0.05) and used as the gold standard for all of the comparisons in this study. The ELISA results indicate that the mean concentration of MIF was significantly higher in patients with positive rose Bengal tests when compared to the control groups and that its concentration increases with increasing age in both the patient and control groups (p ≤ 0.05).

• Journal of Applied Biological Chemistry
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• 제65권2호
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• pp.93-99
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• 2022

Lysosome organelle extract (LOE) was derived from egg whites. The lysosome is an intracellular organelle that contains several hydrolysis enzymes. Previous studies have reported that LOE performs important functions, such as melanin de-colorization and anti-melanin production in B16F10 melanoma cells. However, its principal molecular and cellular mechanisms have not been elucidated till date. In non-cytotoxic conditions, LOE significantly inhibited α-MSH induced melanin synthesis of murine B16F10 cells. The anti-melanogenic activity of LOE was mediated by suppressing the mRNA expression of tyrosinase enzyme, tyrosinase related protein-1/2 (TRP-1/2), and microphthalmia-associated transcription factor (MITF) genes. By performing western blot analysis, we found that LOE significantly attenuated melanogenesis. In this case, LOE helped in increasing extracellular receptor kinase (ERK) phosphorylation in α-MSH induced B16F10 cells. Furthermore, MITF is found to be a key regulatory transcription factor in melanin synthesis; it was down-regulated by LOE through ERK phosphorylation. In this experiment, PD98059 (MEK inhibitor) was used to check whether LOE directly regulated the activity of ERK. Although LOE exerted inhibitory effect on melanin synthesis, we could not observe this effect in PD98059-treated α-MSH induced B16F10. These results strongly indicate that LOE is related to ERK activation and MITF degradation in anti-skin pigmentation. Hence, LOE should be utilized as a whitening agent of skin in the near future.

• 생약학회지
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• 제53권2호
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• pp.79-86
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• 2022

Excessive glutamate causes oxidative stress in neuronal cells, which can cause degenerative neurological disorders. We tried to find medicinal plant showed neuroprotective activity by using glutamate-injured HT22 cell as a model system. In this study, we found that Boesenbergia rotunda methanol extract showed neuroprotective activity against glutamate induced neurotoxicity in mouse hippocampal HT22 cells. B. rotunda methanol extract suppressed the formation of reactive oxygen species and decreased intracellular Ca²⁺concentration. Also, B. rotunda made mitochondrial membrane potential maintain to normal levels. In addition, B. rotunda increased total glutathione amount and activated antioxidative enzyme such as glutathione reductase and glutathione peroxidase compared to glutamate-treated groups. These results suggested that B. rotunda decreased neuronal cell death damaged by high concentrations of glutamate treatment, via antioxidative mechanism and might be one of candidate of development of new drug to treat neurodegenerative disease such as Alzheimer's disease.

• 한국자원식물학회지
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• 제35권6호
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• pp.704-712
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• 2022

Research on whitening materials using natural alternatives is actively being conducted. The aim of this study was to investigate the in vitro inhibitory effects of Ranunculus chinensis Bunge (RCB) on melanogenesis and associated enzymes, such as tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 in B16F10 murine melanoma cells. We found that RCB extract significantly attenuated melanin synthesis and reduced the activity of intracellular tyrosinase, a rate-limiting melanogenic enzyme. Western blot analysis showed that RCB extract decreased the protein expression of tyrosinase and TRP-1. In addition, it significantly decreased the expression of microphthalmia-associated transcription factor (MITF), a key regulator of melanogenesis. Extracellular signal-regulated kinase (ERK) activation has been reported to be involved in the inhibition of melanogenesis. Thus, we investigated whether the hypopigmentary effects of RCB extract were related to the activation of ERK. RCB extract induced ERK phosphorylation in a dose-dependent manner. Furthermore, it markedly inhibited body pigmentation in a zebrafish model. Our results suggest that RCB extract inhibits melanogenesis by activating ERK pathway-mediated suppression of MITF and its downstream target genes, including tyrosinase. Therefore, RCB extract can be used as a whitening agent in the development of functional cosmetics.

• Applied Biological Chemistry
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• 제39권1호
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• pp.60-66
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• 1996

김치에서 분리한 유산균 Lactobacillus(L.) plantarum 3 균주(strain No.49, No.61, No.75)의 ${\beta}-galactosidase$의 생성을 위한 최적 조건을 검토하고, 효소학적 특성을 조사하였다. 효소 ${\beta}-galactosidase$의 최적 생성 조건은 strain No. 49의 경우 탄소원을 dextrose대신에 lactose를, strain No. 75 균주는 galactose를 1.0% 함유한 MRS broth에서, 초기 pH를 6.5로 하여 $30^{\circ}C$에서 48시간 배양하였을 때로 판명되었다. Strain No. 61 균주의 경우는 lactose를 3.0% 함유한 MRS 배지의 초기 pH를 7.5로 하여 실온에서 48시간 배양하였을때가 최적생성조건이었다. 효소의 최적 활성 온도는 $60^{\circ}C,\;37^{\circ}C,\;50^{\circ}C$로 3균주 모두 L. plantarum임에도 불구하고 각각 다른 온도에서 최고 활성을 보였다. 특히, strain No. 61, No. 75는 반응 온도가 상승함에 따라 활성의 감소가 관찰된 반면 strain No. 49는 $60^{\circ}C$의 높은 온도에서 가장 높은 활성을 보여 높은 온도에서도 효소활성이 유지 되는 점은 주목할 만하였으며, 3균주 모두 $45^{\circ}C$까지 90% 이상의 안정성을 나타내었다. 한편 효소의 최적 pH는 3 균주 모두 pH 6.5이었으며, pH 6.0에서 효소활성이 가장 안정하였다.