• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1605-1612
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• 2006

Interleukin (IL)-18, a member of the family of IL-l cytokine, is one of the principal inducers of $interferon-{\gamma}(IFN-{\gamma})$ in T lymphocytes and natural killer cells. The objective of the present study was to evaluate the effect of IL-18 on the expression of chemokine IP-10 (CXCL-10) mRNA in mouse peritoneal macrophages. IL-18 had very weak direct effect or synergistic effect with IL-12 on the expression of IP-10 mRNA in C57BL/6 mouse peritoneal macrophages. However, IL-18 pretreatment was found to playa cooperative role in the expression of lipopolysaccharide (LPS)-induced IP-10 mRNA. For the expression of LPS-induced IP-10 mRNA, the synergistic effect was detected after 16 h of IL-18 pretreatment prior to LPS stimulation. The expression level of CD14 in cells stimulated with LPS was not changed by IL-18 pretreatment, and the level of $IFN-{\gamma}$ production during IL-18 pretreatment plus LPS stimulation was barely discernible ($0.36{\pm}0.31pg/ml$). Namely, the synergistic effect of IL-18 pretreatment was not related to a change of LPS receptor, CD14 expression, and the production of $IFN-{\gamma}$ by the interaction between IL-18 and LPS. The synergistic effect of IL-18 pretreatment on the expression of LPS-induced IP-10 was related to not NF-kB but AP-1 activation, and associated with the extracellular signal-regulated kinase (ERK) pathway, one of the mitogen-activated protein kinase signaling pathways. These results provide useful information that may elucidate the mechanisms underlying the effect of IL-18 on the expression of IP-10 mRNA.

• The Korean Journal of Physiology and Pharmacology
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• 제15권5호
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• pp.273-277
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• 2011

Nitric oxide (NO) and atrial natriuretic peptide (ANP) may induce vascular relaxation by increasing the production of cyclic guanosine monophosphate (cGMP), an important mediator of vascular tone during sepsis. This study aimed to determine whether regulation of NO and the ANP system is altered in lipopolysaccharide (LPS)-induced kidney injury. LPS (10 $mg{\cdot}kg^{-1}$) was injected in the tail veins of male Sprague-Dawley rats; 12 hours later, the kidneys were removed. Protein expression of NO synthase (NOS) and neutral endopeptidase (NEP) was determined by semiquantitative immuno-blotting. As an index of synthesis of NO, its stable metabolites (nitrite/nitrate, NOx) were measured using colorimetric assays. mRNA expression of the ANP system was determined by real-time polymerase chain reaction. To determine the activity of guanylyl cyclase (GC), the amount of cGMP generated in response to sodium nitroprusside (SNP) and ANP was calculated. Creatinine clearance decreased and fractional excretion of sodium increased in LPS-treated rats compared with the controls. Inducible NOS protein expression increased in LPS-treated rats, while that of endothelial NOS, neuronal NOS, and NEP remained unchanged. Additionally, urinary and plasma NOx levels increased in LPS-treated rats. SNP-stimulated GC activity remained unchanged in the glomerulus and papilla in the LPS-treated rats. mRNA expression of natriuretic peptide receptor (NPR)-C decreased in LPS-treated rats, while that of ANP and NPR-A did not change. ANP-stimulated GC activity reduced in the glomerulus and papilla. In conclusion, enhancement of the NO/cGMP pathway and decrease in ANP clearance were found play a role in the pathogenesis of LPS-induced kidney injury.

• 한국식품영양과학회지
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• 제44권12호
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• pp.1763-1770
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• 2015

한방에서 염증 치료 목적으로 사용하는 흰 민들레 뿌리의 열수 추출물을 제조하여 항염증 효과 및 산화 스트레스 개선효과를 확인하고자 하였다. ICR mice에 lipopolysaccharide(LPS)를 1회 복강 투여하여(10 mg/kg bw) 염증 및 산화스트레스를 유발하고, 한국에만 자생하는 흰 민들레 뿌리 열수 추출물을 1.4 g/kg bw 농도로 2회 경구 투여하였다. LPS에 의한 염증 유발은 체중 감소 현상으로 확인하였고, 민들레 뿌리 열수 추출물 투여군은 유의적으로 체중이 증가하여 염증 억제 효과가 관찰되었다. LPS 처리는 혈액의 중성지방질, 혈액 및 간의 reactive oxygen species(ROS), peroxynitrite 농도 그리고 간의 지질과산화 수준을 증가시켰다(P<0.05). LPS를 처리한 대조군에 비해 흰 민들레 뿌리 열수 추출물 투여군은 혈중 및 간의 중성지방질, ROS, peroxynitrite 농도 그리고 간의 지질과산화물 수준이 유의적으로 감소하였다(P<0.05). 이는 흰 민들레 뿌리 열수 추출물이 간의 $NF-{\kappa}B$ 전사인자 및 이의 조절을 받는 COX-2의 단백질 발현을 억제함으로써 염증 관련 매개체 및 유리기 생성을 유의적으로 억제하였기 때문으로 생각된다. LPS 처리군에서 간의 중성지방질 농도가 감소한 것은 염증에 의해 간 조직이 손상되어 중성지방질의 합성이 억제되었기 때문으로 생각된다. 본 연구는 한방에서 사용하여 온 한국 토종 흰 민들레 뿌리가 $NF-{\kappa}B$ 전사인자의 발현을 억제함으로써 염증 및 산화 스트레스를 개선하는 효과가 있음을 확인하였다.

• Natural Product Sciences
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• 제12권2호
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• pp.113-117
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• 2006

Quercitrin gallate was previously isolated from Persicaria lapathifolia (Polygonaceae) as an inhibitor of superoxide production. In the present study, quercitrin gallate was found to inhibit interleukin (IL)-6 production in lipopolysaccharide (LPS)-stimulated macrophages RAW 264.7 with an $IC_{50}$ value of $63\;{\mu}M$. Furthermore, quercitrin gallate attenuated LPS-induced synthesis of IL-6 transcript but also inhibited LPS-induced IL-6 promoter activity, indicating that the compound could down-regulate IL-6 expression at the transcription level. Since nuclear factor (NF)-kB has been shown to play a key role in LPS-inducible IL-6 expression, an effect of quercitrin gallate on LPS-induced NF-kB activation was further analyzed. Quercitrin gallate exhibited a dosedependent inhibitory effect on LPS-induced nuclear translocation of NF-kB without affecting inhibitory kB (IkB) degradation, and subsequently inhibited LPS-induced NF-kB transcriptional activity in macrophages RAW 264.7. Taken together, quercitrin gallate down-regulated LPS-induced IL-6 expression by inhibiting NF-kB activation, which could provide a pharmacological potential of the compound in IL-6-related immune and inflammatory diseases.

• 치위생과학회지
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• 제17권1호
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• pp.81-86
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• 2017

Bacterial infection and smoking are an important risk factors involved in the development and progression of periodontitis. However, the signaling mechanism underlying the host immune response is not fully understood in periodontal lesions. In this study, we determined the expression of janus kinase (JAK)/signal transducer and activator of transcription (STAT) on Porphyromonas gingivalis lipopolysaccharide (LPS)- and nicotine-induced cytotoxicity and the production of inflammatory mediators, using osteoblasts. The cells were cultured with 5 mM nicotine in the presence of $1{\mu}g/ml$ LPS. Cell viability was determined using MTT assay. The role of JAK on inflammatory mediator expression and production, and the regulatory mechanisms involved were assessed via enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, and Western blot analysis. LPS- and nicotine synergistically induced the production of cyclooxgenase-2 (COX-2) and prostaglandin $E_2$ ($PGE_2$) and increased the protein expression of JAK/STAT. Treatment with an JAK inhibitor blocked the production of COX-2 and $PGE_2$ as well as the expression of pro-inflammatory cytokines, such as tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$ ($IL-1{\beta}$), and IL-6 in LPS- and nicotine-stimulated osteoblasts. These results suggest that JAK/STAT is closely related to the LPS- and nicotine-induced inflammatory effects and is likely to regulate the immune response in periodontal disease associated with dental plaque and smoking.

• 한국식품영양과학회지
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• 제33권3호
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• pp.571-575
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• 2004

대장균 O157:H7의 백신 생산을 위해서 purity가 높은 lipopolysacharride 분리, 정제를 위한 실험을 실시하였다. 대장균 O157:H7 균주를 확인하기 위해서 shiga toxin을 생산할 수 있는 60 MDa plasmid를 분리하였고, PCR법에 의해 E. coli O157:H7 shiga-like toxin(Stx) 1, 2의 stx gene을 증폭하여 E. coli O157:H7의 특징 (130 bp, 346 bp)을 확인하였다. E. coli O157:H7 LPS의 분리 정제는 페놀추출, 에탄올 분획 및 gel filtration의 간단한 방법을 사용하였다. 마지막으로 SDS-PAGE와 silver nitrate 염색을 이용하여 LPS의 purity를 확인하였다.

• 대한본초학회지
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• 제32권2호
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• pp.65-75
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• 2017

Objectives : This study aimed to evaluate the protective effect of Orostachydis Herba (OH) and Fermented OH (OHF) against the acute liver injury by lipopolysaccharide (LPS). Methods : OHF by 4 lactic bacteria such as (Lactobacillus hilgardii (OHF1), Leuconostoc mesenteroides (OHF2), Pediococcus acidilactici (OHF3), Saccharomyces cerevisiae (OHF4)) were prepared. Samples were selected to OHF0, OHF2, OHF3 based on UPLC analysis, DPPH, ABTS radical scavenging activities. To evaluate the protective effect of OHF on liver injury mice, ICR mice were divided into 5 groups: Normal mice (Nor), LPS (20 mg/kg) treated mice (Veh), administrated OHF0, OHF2 OHF3 200 mg/kg body weight during 8 days before LPS injection. Serum and liver were collected 24 hours after LPS injection. Results : The activity was high in order of OHF0 and OHF3 in DPPH and ABTS radical scavenging activities. The quercetin contents for bioactive ingredient of OH was 5.39, kaempferol contents was 9.94 by UPLC analysis. The LPS-treated vehicle group significantly increased liver weight, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in serum. In contrast, administrated OHF3 group decreased liver weight, AST, ALT. In addition, OHF3 groups reduced the elevated levels of reactive oxygen species (ROS) in serum and tissues. Moreover, AP-1, iNOS and COX-2 were significantly decreased in OHF2 and OHF3. But $NF-{\kappa}B$ p65 and $TNF-{\alpha}$ only showed a significant reduction in OHF3. Conclusions : Therefore, these results suggest that fermented Orostachydis Herba might be protective effect on liver injury through anti-oxidant effect.

• 생명과학회지
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• 제18권11호
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• pp.1471-1478
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• 2008

본 연구에서는 내독소내성 상태에 있는 마우스 세포의 싸이토카인 생성능을 측정하기 위하여 대식세포-림프구 공동배양계를 이용한 nitric oxide (NO) 생성을 조사하였다. 마우스 복강 대식세포에 lipopolysaccharide (LPS)와 interferon-g (IFN-g)를 처리시 NO 생성이 증가되었으며, tumor necrosis factor-a (TNF-a) 또한 LPS처럼 NO 합성을 자극하는 것을 관찰할 수 있었다. 한편, 대식세포를 비장세포와 공동배양시, LPS 단독처리만으로도 NO 합성이 증가되었다. 반면, 2.5 mg/kg LPS로 전처리하고 치사량의 LPS를 2차 투여한 마우스의 경우, 마우스의 치사 및 혈중 TNF-a와 IFN-g가 증가되지 않았다. 또한 LPS-내성 마우스로부터 분리한 대식세포를 정상 비장세포와 공동배양시 LPS에 의한 NO생성이 일어나지 않았으며, 외래 TNF-a에 의한 NO 생성도 일어나지 않았다. 이와 아울러 정상 대식세포와 LPS 내성 마우스로부터 분리한 비장세포를 공동배양하였을 때, LPS 자극으로 인한 NO 생성이 일어나지 않았으며, 이러한 억제현상은 외래 IFN-g 또는 IFN-g 생성을 촉진시키는 concanavalin A (ConA)에 의해서 다시 역전되었다. 이러한 결과는 대식세포 뿐만 아니라 림프구도 LPS 내성에 관여하는 것을 보여준다고 사료된다. INF-g는 TNF-a 발현을 증가시키기 때문에, 림프구의 INF-g 합성 감소는 LPS에 내성을 보이는 대식세포의 TNF-a 합성 저하와 상호작용으로 내독소내성 상태를 유도하며 과도한 염증반응을 억제하는 것으로 사료된다. 따라서 LPS 내독소내성은 중환자의 심각한 패혈증에 대한 예방법으로 활용될 수 있을 것으로 기대된다.

• 대한한방내과학회지
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• 제28권1호
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• pp.80-91
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• 2007

Objectives : Peroxynitrite (ONOO-), superoxide anion radical (?O2-) and nitric oxide (NO) are cytotoxic because they can oxidize several cellular components such as proteins, lipids and DNA. They have been implicated in the aging process, and age-related diseases such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate Sabohwan's activity for scavenging ONOO- and its precursors. NO and ?02-. Methods : For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4.5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Results : Sabohwanblocked tert-butylhydroperoxide (t-BHP)-induced cell death in a dose-dependent fashion. It scavenged t-BHP-induced ONOO-, NO and ?O2- in YPEN cells. Sabohwan inhibited the generation of ONOO-, NO and ?O2- in the lipopolysaccharide (LPS)-treated mouse kidney postmitochondria both in vitro and in vivo. The lipid peroxide level increased and glutathione level decreased in the LPS-treated mice, whereas the ones in the Sabohwanadministered group among the LPS-treated mice reversed toward their natural levels. Conclusions : These results suggest that Sabohwanis an effective ONOO-, ?O2- and NO scavenger, and thereby it might have a potential role as a therapy against the aging process and age-related diseases.

• 한국약용작물학회지
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• 제15권6호
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• pp.451-456
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• 2007

Curcumin, a polyphenolic antioxidant purified from turmeric, has been known to possess various biological activities such as anti-oxidative, anti-inflammatory and anti-cancer effects. In this study, we have explored anti-inflammatory effect of curcumin using Gram (-) bacterium-derived endotoxin (lipopolysaccharide: LPS) and macrophage cell line RAW264.7. Curcumin suppressed NO production in LPS-activated RAW264.7 cells in a dose-dependent manner, Curcumin also blocked the activation of $NF-{\kappa}B$ but not AP-1 according to luciferase assay. Furthermore, this compound suppressed the phosphorylation of a series of intracellular signaling components such as Src, JAK-2, Akt, IKK and $I{\kappa}B{\alpha}$ under LPS stimulation in a time dependent manner, Therefore, our data suggest that curcumin was able to protect the host from Gram(-) bacterial-infection-mediated inflammatory symptoms.