• 미생물학회지
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• 제26권4호
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• pp.362-367
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• 1988

The strain YL 38-3, which was capable of producing extracellular cytosine deaminase, was isolated and taxonomically examined. The isolated strain was identified to be Bacillus polymyxa YL 38-3. The optimal conditions for the enzyme production from Bacillus polymyxa YL 38-3 were investigated. The enzyme production was reached maximum level in the medium containing 0.5% glucose, 0.2% beef extract, 0.5% NaCl and 0.1% $KH_{2}PO_{4}$ (pH 6.0). And the enzyme showed the highest activity when the strain YL 38-3 was cultivated at $35^{\circ}C$ for 24 gours under the initial pH 6.0. By the additions of peptone the extracellular enzyme production was inhibited, meanwhile the intracellular enzyme production was highly stimulated. It was, therefore, deduced that peptone was related to the secretion mechanism of the enzyme from this bacterial cell.

• IMMUNE NETWORK
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• 제6권4호
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• pp.204-210
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• 2006

Background: Nitric oxide (NO) in articular chondrocytes regulates dedifferentiation and inflammatory responses by modulating MAP kinases. In this study, we investigated whether the Src kinase in chondrocytes regulates NO-induced dedifferentiation and cyclooxygenase-2 (COX-2) expression. Methods: Primary chondrocytes were treated with various concentrations of SNP for 24 h. The COX-2 and type II collagen expression levels were determined by immunoblot analysis, and prostaglandin $E_2\;(PGE_2)$ was determined by using a $PGE_2$ assay kit. Expression and distribution of p-Caveolin and COX-2 in rabbit articular chondrocytes and cartilage explants were determined by immunohistochemical staining and immunocytochemical staining, respectively. Results: SNP treatment stimulated Src kinase activation in a dose-dependent manner in articular chondrocytes. The Src kinase inhibitors PP2 [4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo(3,4-d)pyrimidine], a significantly blocked SNP-induced p38 kinase and caveolin-1 activation in a dose-dependent manner. Therefore, to determine whether Src kinase activation is associated with dedifferentiation and/or COX-2 expression and $PGE_2$ production. As expected, PP2 potentiated SNP-stimulated dedifferentiation, but completely blocked both COX-2 expression and $PGE_2$ production. And also, levels of p-Caveolin and COX-2 protein expression were increased in SNP-treated primary chondrocytes and osteoarthritic and rheumatoid arthritic cartilage, suggesting that p-Caveolin may playa role in the inflammatory responses of arthritic cartilage. Conclusion: Our previously studies indicated that NO caused dedifferentiation and COX-2 expression is regulated by p38 kinase through caveolin-1 (1). Therefore, our results collectively suggest that Src kinase regulates NO-induced dedifferentiation and COX-2 expression in chondrocytes via p38 kinase in association with caveolin-1.

• 치위생과학회지
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• 제14권2호
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• pp.240-247
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• 2014

본 연구에서는 formalin으로 유발된 악안면 염증성 통증모델에서 acaiberry의 진통작용과 항산화작용을 확인하고자 하였다. 실험동물의 악안면 통증은 수염부에 5% formalin ($50{\mu}l$)을 주입하여 유발하였고 45분간 행위반응을 측정하였다. Acaiberry의 통증행위반응 조절효과를 확인하기 위해 formalin 주입 30분 전 실험동물에게 복강투여 하였다. Acaiberry의 통증행위반응조절에 대한 생리적 기전을 확인하기 위해 항염증과 항산화의 지표인 p38 MAPK의 활성 및 NOX4의 발현을 단백정량분석법을 통해 평가하였다. Acaiberry (16, 80, 160 mg/kg)의 복강투여는 실험동물의 통증행위반응을 대조군($290{\pm}17.4$)에 비해 농도 의존적($205.3{\pm}21.8$, $137.8{\pm}21.8$, $53.5{\pm}30.2$)으로 감소시켰다. 이러한 통증행위반응은 시간의 경과에 따라 변화를 나타내었다. Formalin의 주입으로 인한 통증행위반응은 15분 이후부터 증가하여 25분, 30분에 가장 높게 나타났으며 40분까지 지속되다가 45분에 감소되었으며, 15~40분에서 증가되었던 통증행위반응은 acaiberry의 복강투여로 인해 현저하게 감소되었다. 또한 acaiberry의 복강투여는 실험동물의 연수와 부신에서 p38 MAPK활성 및 NOX4의 발현을 감소시켰다. Acaiberry은 포르말린으로 유도한 악안면 통증에서 실험동물의 통증행위반응을 유의하게 감소시켰으며, 이는 p38 MAPK 및 NOX4 경로의 조절을 통한 항염증 및 항산화 작용에 의한 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5835-5842
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• 2015

Background: Melatonin, which is mainly produced by the pineal gland, has a good inhibitory effect on cell growth of multiple cancer types. However, the underlying molecular mechanisms of anti-tumor activity for colon cancer have not been fully elucidated. In this study, we investigated the effects of melatonin on migration in human colon cancer RKO cells and the potential molecular mechanisms. Materials and Methods: The viability of RKO cells was investigated by MTT assay after treatment with melatonin, SB203580 (p38 inhibitor) and phorbol 12-myristate 13-acetate (PMA, MAPK activator) alone or in combination for 48h. The effects of melatonin, and ML-7, a selective inhibitor of myosin light chain kinase (MLCK), and SB203580, and PMA on the migration of RKO cells were analyzed by in vitro scratch-wound assay. The relative mRNA levels of MLCK was assessed by real-time quantitative RT-PCR. Western blotting analysis was performed to examine the expression of MLCK, phosphorylation of myosin light chain (pMLC) and p38 (pp38). Results: The proliferation and migration of human colon cancer RKO cells were inhibited significantly after treatment with melatonin. The expression levels of MLCK and phosphorylation of MLC of RKO cells were reduced, and real-time quantitative RT-PCR showed that melatonin had significant effects on suppressing the expression of MLCK. Furthermore, the phosphorylation level of p38, which showed the same trend, was also reduced when cells were treated by melatonin. In addition, ML-7 (25umol/l) could down-regulate the phosphorylation of p38. Conclusions: Melatonin could inhibit the proliferation and migration of RKO cells, and further experiments confirmed that p38 MAPK plays an important role in regulating melatonin-induced migration inhibition through down-regulating the expression and activity of MLCK.

• 대한의생명과학회지
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• 제9권2호
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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.

• Journal of Ginseng Research
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• 제47권6호
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• pp.714-725
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• 2023

Background: Our previous investigation indicated that the preparation of Panax ginseng Meyer (P. ginseng) inhibited melanogenesis. It comprised salicylic acid (SA), protocatechuic acid (PA), p-coumaric acid (p-CA), vanillic acid (VA), and caffeic acid (CA). In this investigation, the regulatory effects of P. ginseng phenolic acid monomers on melanin production were assessed. Methods: In vitro and in vivo impact of phenolic acid monomers were assessed. Results: SA, PA, p-CA and VA inhibited tyrosinase (TYR) to reduce melanin production, whereas CA had the opposite effects. SA, PA, p-CA and VA significantly downregulated the melanocortin 1 receptor (MC1R), cycle AMP (cAMP), protein kinase A (PKA), cycle AMP-response element-binding protein (CREB), microphthalmia-associated transcription factor (MITF) pathway, reducing mRNA and protein levels of TYR, tyrosinase-related protein 1 (TYRP1), and TYRP2. Moreover, CA treatment enhanced the cAMP, PKA, and CREB pathways to promote MITF mRNA level and phosphorylation. It also alleviated MITF protein level in α-MSH-stimulated B16F10 cells, comparable to untreated B16F10, increasing the expression of phosphorylation glycogen synthase kinase 3β (p-GSK3β), β-catenin, p-ERK/ERK, and p-p38/p38. Furthermore, the GSK3β inhibitor promoted p-GSK3β and p-MITF expression, as observed in CA-treated cells. Moreover, p38 and ERK inhibitors inhibited CA-stimulated p-p38/p38, p-ERK/ERK, and p-MITF increase, which had negative binding energies with MC1R, as depicted by molecular docking. Conclusion: P. ginseng roots' phenolic acid monomers can safely inhibit melanin production by bidirectionally regulating melanin synthase transcription. Furthermore, they reduced MITF expression via MC1R/cAMP/PKA signaling pathway and enhanced MITF post-translational modification via Wnt/mitogen-activated protein kinase signaling pathway.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.433-438
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• 1991

Phenylalanine 고생산용 plasmid pSY130-14는 $\lambda$-phage 유래 온도감수성을 가지고 있으므로 $cI_{857}$ repressor와 PL과 PR을 온도를 올려 phenylalanine의 생산을 유도한다. pSY130-14를 갖는 E.coli AT2471은 kanamycin 무첨가, $38.5^{\circ}C$, 48시간에서 약 30%로 plasmid가 없어지며 첨가에서 안정성이 떨어졌다가 배양시간과 더불어 올라갔는데, 이것은 생육에 피요한 kanamycin gene과 ori만이 남는 것으로 생각된다.

• International Journal of Oral Biology
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• 제31권1호
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• pp.21-26
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• 2006

Periodontopathogens including Porphyromonas gingivalis interact with host periodontal cells and the excessive subsequent host responses contribute a major part to the development of periodontal diseases. Cyclooxygenase(COX)-2-synthesized $PGE_2$ has detrimental activities in terms of periodontal pathogenesis. The present study investigated induction of COX-2 expression by P. gingivalis in human monocytic THP-1 cells. Live P. gingivalis increased expression of COX-2, but not that of COX-1, which was demonstrated at both mRNA and protein levels. Elevated levels of $PGE_2$ were released from P. gingivalis-infected THP-1 cells. Pharma-cological inhibition of p38 mitogen-activated protein kinase(MAPK) and extracellular signal-regulated kinase(ERK) substantially attenuated P. gingivalis-induced COX-2 mRNA expression. Indeed, activation of p38 MAPK and ERK was observed in P. gingivalis-infected THP-1 cells. Also, P. gingivalis induced activation of nuclear $factor-{\kappa}B\;(NF-{\kappa}B)$ which is an important transcription factor for COX-2. These results suggest that COX-2 expression is up regulated in P. gingivalis-infected monocytic cells, at least in part, via p38 MAPK, ERK, and $NF-{\kappa}B$.

• 한국식품위생안전성학회지
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• 제12권4호
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• pp.310-314
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• 1997

Antithiamin activities of BHA, BHT, PG and TBHQ of synthetic antioxidants on the effect of temperature and pH was determined by means of HPLC. The influence of synthetic antioxidants on the degration of thiamin was found to be dependent on temperature and pH. The degradation of thiamin was considerably more rapid at pH 7 than pH 4. The influence on the heat of synthetic antioxidants at pH 4 and 38* was extremely slight, but the degradation of thiamin at pH 7 was much more rapid at 60* than at 38*. After 24 hours of incubation both PG and TBHQ at pH 7 and 60* nearly completely destroyed thiamin. Tests of antithiamin activities showed that TBHQ, which was decomposed completely in 72 hours, was more effective than PG at pH 7 and 38* but BHA and BHT hardly had antithiamin activities which was evaluated under various reactions of pH and temperature. Thiamin degradation, at pH 7 and 6$0^{\circ}C$, was proportional to the concentration of PG. When the ratio of PG to thiamin was increased from 0.15:1 to 2:1, the degradation rate also increased. However, the change between ratio of 1:1 and 2:1 was negligible.

• Nutrition Research and Practice
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• 제8권4호
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• pp.368-376
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• 2014

BACKGROUND/OBJECTIVES: The objectives of this study were to investigate the effects of lycopene on the migration, adhesion, tube formation capacity, and p38 mitogen-activated protein kinase (p38 MAPK) activity of endothelial progenitor cells (EPCs) cultivated with high glucose (HG) and as well as explore the mechanism behind the protective effects of lycopene on peripheral blood EPCs. MATERIALS/METHODS: Mononuclear cells were isolated from human peripheral blood by Ficoll density gradient centrifugation. EPCs were identified after induction of cellular differentiation. Third generation EPCs were incubated with HG (33 mmol/L) or 10, 30, and $50{\mu}g/mL$ of lycopene plus HG. MTT assay and flow cytometry were performed to assess proliferation and apoptosis of EPCs. EPC migration was assessed by MTT assay with a modified boyden chamber. Adhesion assay was performed by replating EPCs on fibronectin-coated dishes, after which adherent cells were counted. In vitro vasculogenesis activity was assayed by Madrigal network formation assay. Western blotting was performed to analyze protein expression of both phosphorylated and non-phosphorylated p38 MAPK. RESULTS: The proliferation, migration, adhesion, and in vitro vasculogenesis capacity of EPCs treated with 10, 30, and $50{\mu}g/mL$ of lycopene plus HG were all significantly higher comapred to the HG group (P < 0.05). Rates of apoptosis were also significantly lower than that of the HG group. Moreover, lycopene blocked phosphorylation of p38 MAPK in EPCs (P < 0.05). To confirm the causal relationship between MAPK inhibition and the protective effects of lycopene against HG-induced cellular injury, we treated cells with SB203580, a phosphorylation inhibitor. The inhibitor significantly inhibited HG-induced EPC injury. CONCLUSIONS: Lycopene promotes proliferation, migration, adhesion, and in vitro vasculogenesis capacity as well as reduces apoptosis of EPCs. Further, the underlying molecular mechanism of the protective effects of lycopene against HG-induced EPC injury may involve the p38 MAPK signal transduction pathway. Specifically, lycopene was shown to inhibit HG-induced EPC injury by inhibiting p38 MAPKs.