• Title/Summary/Keyword: NO production inhibitors

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Taxonobic Characteristics of Strain Producing MR-387A and B,New Inhibitors of Aminopeptidase M,and their Production (신규의 Aminopeptidase M 저해제 MR-387A와 B를 생산하는 균주의 동정 및 저해제의 생산)

  • Chung, Myung-Chul;Chun, Hyo-Kon;Lee, Ho-Jae;Kho, Yung-Hee
    • Microbiology and Biotechnology Letters
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    • v.22 no.5
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    • pp.447-452
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    • 1994
  • The strain SL-387 which produces new inhibitors of aminopeptidase M, MR-387A and B, was isolated from a soil sample. The strain has branched substrate mycelia, from which aerial hyphae develop in the form of open spirals. Spore surface is smooth. Melanoid and soluble pigme- nts were observed. The isolate contains LL-diaminopimelic acid in its cell wall hydrolysate, and has no pectinolytic activity. The strain SL-387 is closely related to Streptomyces griseoruber and S. naganishii, but is different from these strains in some cultural and physiological characteristics. This strain was, therefore, designated as Streptomyces sp. SL-387. The effects of several carbon and nitrogen sources on the production of the inhibitor were examined. Among them, glucose, galactose, mannose, and xylose were effective as a carbon source and soybean meal, soytone, fish meal, and gluten meal were effective as a nitrogen source. The maximum peak of the inhibitor production in jar fermentor was obtained on the fifth day of culture.

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Effect of nitric oxide on the expression of matrix metalloproteinases by the UV irradiated human dermal fibroblasts

  • Taeboo Choe;Lee, Bumchun;Park, Inchul;Seokil Hong
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.28 no.1
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    • pp.31-41
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    • 2002
  • The production of matrix matalloproteinases(MMPs) by the UV irradiated skin fibroblast and the degradation of extracellular matrix(ECM) by these enzymes is known as one of the main reasons of photoaging. Recently, Fisher group showed that the MMP expression is mainly regulated by the mitogen-activated protein(MAP) kinas family, such as extracellular signal-regulated kinase(ERK), c-Jun amino-terminal kinase(JNK) and p38, each of which forms a signaling pathway. In this work we first examined the effect of nitric oxide (NO) on the production of MMP-1 and MMP-2 by the human dermal fibroblasts (HDFs). NO is a multifunctional messenger molecule generated from L-arginine and involved in many kinds of signaling pathway. We found that the treatment of HDF with NO donor, sodium nitroprusside (SNP) enhanced the expression of MMPs with or without UV irradiation and the treatment with nitric oxide synthase (NOS) inhibitors resulted in the significant decrease of MMPs production. From these results, we concluded that the production of MMPs by the UV irradiated HDF is regulated through the signaling pathway involving NO and cyclic GMP.

Inhibitory Activity of Chinese Medicinal Plants on Nitric Oxide Synthesis in Lipopolysaccharide -Activated Macrophages

  • Ryu, Jae-Ha;Ahn, Han-Na;Lee, Hwa-Jin;Feng, Li;Qun, Wen-He;Han, Yong-Nam;Han, Byung-Hoon
    • Biomolecules & Therapeutics
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    • v.9 no.3
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    • pp.183-187
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    • 2001
  • Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

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Study on the Action by PAF on IL-1 Modulation in Alveolar Macrophages: Involvement of Endogenous Arachidonate Metabolites and Intracellular $Ca^{++}$ Mobilization

  • Lee, Ji-Hee;Kim, Won-Ki;Hah, Jong-Sik
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.2
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    • pp.241-249
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    • 1998
  • Platelet-activating factor(PAF) enhanced interleukin-1(IL-1) activity by the interaction with a specific receptor in rat alveolar macrophages. In this study, we investigated the role of endogenous arachidonate metabolites and intracellular calcium mobilization in the PAF-induced IL-1 activity. Alveolar macrophages were preincubated with 5-lipoxygenase and cyclooxygenase inhibitors 30 min before the addition of PAF and lipopolysaccharide(LPS). After 24h culture, IL-1 activity was measured in the supernate of sample using the thymocyte proliferation assay. Inhibition of 5-lipoxygenase by nordihydroguaiaretic acid and AA-861 completely blocked the PAF-induced enhancement of IL-1 activity with $IC_{50}\;of\;2\;{\mu}M\;and\;5\;{\mu}M$, respectively. In contrast, the inhibition of cyclooxygenase pathway by indomethacin and ibuprofen resulted in the potentiation in PAF-induced IL-1 activity with maximal effect at $1\;{\mu}M\;and\;5\;{\mu}M$, respectively. In addition, leukotriene $B_4$ and prostaglandin $E_2$ production were observed in PAF-stimulated alveolar macrophage culture. As could be expected, 5-lipoxygenase and cyclooxygenase inhibitors abolished PAF- stimulated leukotriene $B_4$ and prostaglandin $E_2$ production, respectively. The effects of PAF on intracellular calcium mobilization in alveolar macrophages were evaluated using the calcium-sensitive dye fura-2 at the single cell level. PAF at any dose between $10^{-16}\;and\;10^{-8}$ M did not increase intracellular calcium. Furthermore, there was no effective change of intracellular calcium level when PAF was added to alveolar macrophages in the presence of LPS or LPS+LTB4, and 4, 24 and 48h after treatment of these stimulants. Together, the results indicate that IL-1 activity induced by PAF is differently regulated through subsequent induction of endogenous 5-lipoxygenase and cyclooxygenase pathways, but not dependent on calcium signalling pathway.

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Cilostazol Attenuates 4-hydroxynonenal-enhanced CD36 Expression on Murine Macrophages via Inhibition of NADPH Oxidase-derived Reactive Oxygen Species Production

  • Yun, Mi-Ran;Park, Hye-Mi;Seo, Kyo-Won;Kim, Chae-Eun;Yoon, Jung-Wook;Kim, Chi-Dae
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.2
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    • pp.99-106
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    • 2009
  • Although anti-atherogenic effects of cilostazol have been suggested, its effects on the expression of SR in macrophages are unclear. This study investigated the role of cilostazol on CD36 expression of murine macrophages enhanced by HNE, a byproduct of lipid peroxidation. The stimulation of macrophages with HNE led to an increased expression of CD36, which was significantly attenuated by NAC, an antioxidant. Moreover, the increased production of ROS by HNE was completely abolished by NADPH oxidase inhibitors, DPI and apocynin, as well as by the 5-LO inhibitor, MK886, but not by inhibitors for other oxidases. This suggested that NADPH-oxidase and 5-LO were major sources of ROS induced by HNE. In addition, HNE-enhanced expression of CD36 was reduced by these inhibitors, which indicated a role for NADPH oxidase and 5-LO on CD36 expression. In our present study, cilostazol was a significant inhibitor of ROS production, as well as CD36 expression induced by HNE. An increase in NADPH oxidase activity by HNE was significantly attenuated by cilostazol, however cilostazol had no effect on HNE-enhanced 5-LO activity. Together, these results suggest that cilostazol attenuates HNE-enhanced CD36 expression on murine macrophages thorough inhibition of NADPH oxidase-derived ROS generation.

Suppression of nitric oxide and interleukin-6 production by methanol extract of Sophorae Flos in macrophage cells (괴화 추출물이 대식세포에서의 nitric oxide와 interleukin-6의 생성에 미치는 영향)

  • Lee, Ji-Eun;Lee, Ju-Youn;Choi, Jeom-Il;Kim, Chong-Kwan;Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
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    • v.35 no.1
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    • pp.9-19
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    • 2005
  • Both nitric oxide (NO) and interleukin-6 (IL-6) have been thought to have a role in the pathogenesis of inflammatory periodontal disease as it does in other inflammatory diseases, and the inhibitors of NO and IL-6 production have been considered as potential anti-inflammatory agents. In this study, we evaluated methanol extract of Sophorae Flos for inhibition of NO and IL-6 production in Prevotella intermedia LPS-induced mouse macrophages RAW264.7 cells. Dried Sopharae Flos was sliced, and extracted with 100% methanol. LPS from p. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. NO production was assayed by measuring the accumulation of nitrite in culture supematants and IL-6 was measured using mouse IL-6 ELISA kit. Western blot analysis of iNOS and analysis of reverse transcription (RT)-PCR products were carried out. The methanol extract of Sophorae Flos concentration-dependently reduced the production of NO and the expression of iNOS protein and mRNA in RAw264.7 cells treated with P. intermedia LPS. Sophorae Flos also suppressed IL-6 production and the expression of IL-6 mRNA in RAw264.7 cells stimulated by P. intermedia LPS. The inhibition of NO and IL-6 production by Sophorae Flos may be useful in the therapy of inflammatory diseases such as periodontitis. This hypothesis, however, remains to be tested.

Role of $NF-_{{\kappa}B}$ Binding Sites in the Regulation of Inducible Nitric Oxide Synthase by Tyrosine Kinase

  • Ryu, Young-Sue;Hong, Jang-Hee;Lim, Jong-Ho;Bae, So-Hyun;Ahn, Ihn-Sub;Seok, Jeong-Ho;Lee, Jae-Heun;Hur, Gang-Min
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.1
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    • pp.55-63
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    • 2001
  • In macrophages, lipopolysaccharide (LPS) alone or in combination with $interferon-{\gamma}\;(IFN-{\gamma})$ has been shown to release a nitric oxide (NO) through the increase of the transcription of the inducible nitric oxide synthase (iNOS) gene. To investigate the exact intracellular signaling pathway of the regulation of iNOS gene transcription by LPS plus $IFN-{\gamma},$ the effects of protein tyrosine kinase (PTK) inhibitor and protein kinase C (PKC) inhibitors on NO production, iNOS mRNA expression, nuclear $factor-_{\kappa}B\;(NF-_{\kappa}B)$ binding activity and the promoter activity of iNOS gene containing two $NF-_{\kappa}B$ sites have been examined in a mouse macrophage RAW 264.7 cells. LPS or $IFN-{\gamma}$ stimulated NO production, and their effect was enhanced synergistically by mixture of LPS and $IFN-{\gamma}.$ The PTK inhibitor such as tyrphostin reduced LPS plus $IFN-{\gamma}-induced$ NO production, iNOS mRNA expression and $NF-_{\kappa}B$ binding activity. In contrast, PKC inhibitors such as H-7, Ro-318220 and staurosporine did not show any effect on them. In addition, transfection of RAW 264.7 cells with iNOS promoter linked to a CAT reporter gene revealed that tyrphostin inhibited the iNOS promoter activity through the $NF-_{\kappa}B$ binding site, whereas PKC inhibitors did not. Taken together, these suggest that PTK, but not PKC pathway, is involved in the regulation of the iNOS gene transcription through the $NF-_{\kappa}B$ sites of iNOS promoter in RAW 264.7 macrophages by LPS plus $IFN-{\gamma}$.

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Polyacetylene Compound from Cirsium japonicum var. ussuriense Inhibits the LPS-Induced Inflammatory Reaction via Suppression of NF-κB Activity in RAW 264.7 Cells

  • Kang, Tae-Jin;Moon, Jung-Sun;Lee, Sook-Yeon;Yim, Dongs-Sool
    • Biomolecules & Therapeutics
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    • v.19 no.1
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    • pp.97-101
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    • 2011
  • Cirsium japonicum var. ussuriense is known to have a variety of biological activities, including anti-inflammatory, analgesic activity and antipyretic activity. In this study we investigated the role of polyacetylene compound, 1-Heptadecene-11, 13-diyne-8, 9, 10-triol (PA) from the root of Cirsium japonicum var. ussuriense as an immune-modulator. PA was evaluated as inhibitors of some macrophage functions involved in the inflammatory process. We tested the effect of PA on the production of pro-inflammatory cytokines, interleukin-1beta (IL-$1{\beta}$) and tumor necrosis factor-alpha (TNF-$\alpha$), and nitric oxide (NO) in murine macrophage cell line, RAW264.7. There was no effect on cytokine production of macrophages by PA itself. However, PA inhibited lipopolysaccharide (LPS)-induced IL-$1{\beta}$ and TNF-$\alpha$ production by macrophages at a dose dependent manner. PA also suppressed the NO production of macrophages by LPS. LPS-induced NF-${\kappa}B$ activity was decreased by treatment of PA. Therefore, these results suggest that PA has anti-inflammatory effect by inhibiting the NF-${\kappa}B$ activation.

Differential Signaling and Virus Production in Calu-3 Cells and Vero Cells upon SARS-CoV-2 Infection

  • Park, Byoung Kwon;Kim, Dongbum;Park, Sangkyu;Maharjan, Sony;Kim, Jinsoo;Choi, Jun-Kyu;Akauliya, Madhav;Lee, Younghee;Kwon, Hyung-Joo
    • Biomolecules & Therapeutics
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    • v.29 no.3
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    • pp.273-281
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    • 2021
  • Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19) pandemic. Signaling pathways that are essential for virus production have potential as therapeutic targets against COVID-19. In this study, we investigated cellular responses in two cell lines, Vero and Calu-3, upon SARS-CoV-2 infection and evaluated the effects of pathway-specific inhibitors on virus production. SARS-CoV-2 infection induced dephosphorylation of STAT1 and STAT3, high virus production, and apoptosis in Vero cells. However, in Calu-3 cells, SARS-CoV-2 infection induced long-lasting phosphorylation of STAT1 and STAT3, low virus production, and no prominent apoptosis. Inhibitors that target STAT3 phosphorylation and dimerization reduced SARS-CoV-2 production in Calu-3 cells, but not in Vero cells. These results suggest a necessity to evaluate cellular consequences upon SARS-CoV-2 infection using various model cell lines to find out more appropriate cells recapitulating relevant responses to SARS-CoV-2 infection in vitro.

Nitric Oxide Signal Transduction and Its Role in Skin Sensitization

  • Jong Hun Kim;Min Sik Choi
    • Biomolecules & Therapeutics
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    • v.31 no.4
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    • pp.388-394
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    • 2023
  • Nitric oxide (NO) is a signaling molecule that plays a crucial role in numerous cellular physiological processes. In the skin, NO is produced by keratinocytes, fibroblasts, endothelial cells, and immune cells and is involved in skin functions such as vasodilation, pigmentation, hair growth, wound healing, and immune responses. NO modulates both innate and adaptive immune responses. As a signaling molecule and cytotoxic effector, NO influences the function of immune cells and production of cytokines. NO is a key mediator that protects against or contributes to skin inflammation. Moreover, NO has been implicated in skin sensitization, a process underlying contact dermatitis. It modulates the function of dendritic cells and T cells, thereby affecting the immune response to allergens. NO also plays a role in contact dermatitis by inducing inflammation and tissue damage. NO-related chemicals, such as nitrofatty acids and nitric oxide synthase (NOS) inhibitors, have potential therapeutic applications in skin conditions, including allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). Further research is required to fully elucidate the therapeutic potential of NO-related chemicals and develop personalized treatment strategies for skin conditions.