• 생명과학회지
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• 제34권7호
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• pp.443-452
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• 2024

아가로오스의 효소가수분해산물로 부터 확보할 수 있는 3,6-무수갈락토오스(L-AHG), 네오아가로비오스(NA2), 네오아가로테트라오스(NA4) 및 네오아가로헥사오즈(NA6)의 항염증 활성을 규명하고자, 마우스 대식세포주 RAW264.7 세포를 대장균 유래 지질다당류(LPS)로 자극할 때 세포표면의 TLR4 수용체의 역할을 통해 유도되는 친염증성 M1 분극화 및 이에 따른 친염증성 반응에 미치는 영향을 조사하였다. 그 결과로서, 이들 아가로오스 분해산물들 중에서 단당류인 L-AHG만이 유일하게, LPS 자극에 의해 RAW264.7 세포에서 유도될 수 있는 M1 분극화의 대표적인 마커인 iNOS 효소의 발현과 이에 따른 NO 생성을 농도의존적으로 현저하게 저해하였고 염증 매개체인 프로스타글란딘 E2의 생성을 촉매하는 COX-2의 발현 수준도 LPS 자극후에는 증가하였지만, L-AHG의 존재에 의해서는 그 증가 수치가 다소 저해되는 것으로 나타났다. 이때 RAW264.7 세포에 대한 L-AHG의 세포독성은 확인되지 않았다. 또한 L-AHG는 LPS로 처리된 RAW264.7 세포내에서 유도되는 친염증 신호전달경로에 있어서 초기 신호전달 단계인 TAK1 활성화 단계까지는 별 영향을 나타내지 않았으나 TAK1의 촉매작용에 의한 JNK 및 p38 MAPK의 활성화 인산화(activating phosphorylation)는 현저하게 저해되었다. 특히, 대식세포의 친염증 신호전달경로에서 TAK1 활성화는, 그 하류 단계에서 NF-kB의 활성화가 성공적으로 일어날 수 있도록 해주며, 또한 TAK1에 의한 하류 신호분자인 p38 MAPK 활성화는 NADPH 활성화 및 이에 따른 친염증성 ROS 분자들의 생성을 유발하기 때문에, LPS에 의해 자극된 대식세포내의 친염증 신호전달경로에 있어서 TAK1-JNK/p38 MAPK 경로의 L-AHG에 의한 저해는 대식세포의 M1 분극화 및 친염증 반응을 억제하는 효과적인 기전이 되며, 그 활용성이 크게 기대된다. 아울러 L-AHG가 LPS와 RAW264.7 세포의 표면분자인 TLR4와 상호작용을 방해할 수 있는지에 대해서도 유세포분석기와 형광표지가 된 FITC-LPS를 이용하여 조사한 결과, L-AHG는 대식세포의 표면에서 이루어지는 LPS-TLR4 상호결합은 방해하지 않는 것으로 확인되었다. 이는 L-AHG의 항염증 작용의 표적이 LPS가 TLR4 수용체를 통해 유도하는 세포 내 신호전달경로에 있음을 지지해 준다. 이상의 연구결과들은 아가로오스 유래 희귀 단당류인 3,6-무수갈락토오스(L-AHG)가 LPS 자극에 의해 유발되는 RAW264.7 마우스 대식세포의 M1 분극화 및 염증 반응에 대해, TLR4의 친염증 신호전달경로의 TAK1-JNK/p38 MAPK 단계를 저해하는 항염증 활성을 효과적으로 발휘할 수 있음을 시사한다.

• Nutrition Research and Practice
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• 제8권5호
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• pp.487-493
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• 2014

BACKGROUND/OBJECTIVES: D. candidum is a traditional Chinese food or medicine widely used in Asia. There has been little research into the anticancer effects of D. candidum, particularly the effects in colon cancer cells. The aim of this study was to investigate the anticancer effects of D. candidum in vitro and in vivo. MATERIALS/METHODS: The in vitro anti-cancer effects on HCT-116 colon cancer cells and in vivo anti-metastatic effects of DCME (Dendrobium canidum methanolic extract) were examined using the experimental methods of MTT assay, DAPI staining, flow cytometry analysis, RT-PCR, and Western blot analysis. RESULTS: At a concentration of 1.0 mg/mL, DCME inhibited the growth of HCT-116 cells by 84%, which was higher than at concentrations of 0.5 and 0.25 mg/mL. Chromatin condensation and formation of apoptotic bodies were observed in cancer cells cultured with DCME as well. In addition, DCME induced significant apoptosis in cancer cells by upregulation of Bax, caspase 9, and caspase 3, and downregulation of Bcl-2. Expression of genes commonly associated with inflammation, NF-${\kappa}B$, iNOS, and COX-2, was significantly downregulated by DCME. DCME also exerted an anti-metastasis effect on cancer cells as demonstrated by decreased expression of MMP genes and increased expression of TIMPs, which was confirmed by the inhibition of induced tumor metastasis in colon 26-M3.1 cells in BALB/c mice. CONCLUSIONS: Our results demonstrated that D. candidum had a potent in vitro anti-cancer effect, induced apoptosis, exhibited anti-inflammatory activities, and exerted in vivo anti-metastatic effects.

• The Korean Journal of Physiology and Pharmacology
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• 제21권5호
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• pp.465-474
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• 2017

The aim of this study was to determine the raising anticancer effects of resveratrol (Res) on paclitaxel (PA) in non-small cell lung cancer (NSCLC) cell line A549. The $10{\mu}g/ml$ of Res had no effect on human fetal lung fibroblast MRC-5 cells or on A549 cancer cells and the 5 or $10{\mu}g/ml$ of PA also had no effect on MRC-5 normal cells. PA-L ($5{\mu}g/ml$) and PA-H ($10{\mu}g/ml$) had the growth inhibitory effects in NSCLC cell line A549, and Res increased these growth inhibitory effects. By flow cytometry experiment, after Res ($5{\mu}g/ml$)+PA-H ($10{\mu}g/ml$) treatment, the A549 cells showed the most apoptosic cells compared to other group treatments, and after additional treatment with Res, the apoptosic cells of both two PA concentrations were raised. Res+PA could reduce the mRNA and protein expressions of COX-2, and Res+PA could reduce the COX-2 related genes of VEGF, MMP-1, MMP-2, MMP-9, $NF-{\kappa}B$, Bcl-2, BclxL, procollagen I, collagen I, collagen III and CTGF, $TNF-{\alpha}$, $IL-1{\beta}$, iNOS and raise the TIMP-1, TIMP-2, TIMP-3, $I{\kappa}B-{\alpha}$, p53, p21, caspase-3, caspase-8, caspase-9, Bax genes compared to the control cells and the PA treated cells. From these results, it can be suggested that Res could raise the anticancer effects of PA in A549 cells, thus Res might be used as a good sensitizing agent for PA.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.61-64
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• 2002

We have optimally designed and implemented by a monolithic microwave integrated circuit(MMIC) the low noise amplifier(LNA) of 5.8GHz band composed of receiver front-end(RFE) in a on-board equipment system for dedicated short range communication using a depletion-mode GaAs MESFET. The LNA is provided with two active devices, matching circuits, and two drain bias circuits. Operating at a single supply of 3V and a consumption current of 18㎃, The gain at center frequency 5.8GHz is 13.4dB, Noise figure(NF) is 1.94dB, Input 3rd order intercept point(lIPS) is 3dBm, and Input return loss(5$_{11}$) and Output return loss(S$_{22}$) is -l8dB and -13.3dB, respectively. The circuit size is 1.2$\times$O.7$\textrm{mm}^2$.EX>.>.

• 대한전자공학회논문지TE
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• 제39권4호
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• pp.409-412
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• 2002

IMT-2000 전 대역(1920∼2170MHz, BW=250MHz)에서 사용되는 중계기용 2단 저잡음 증폭기를 설계하였다. Ansoft사의 Serenade를 이용하여 첫째 단 PHEMT의 소스와 접지간 source lead의 인덕턴스 값을 최적화하여 기판 선고로 등가화하고, 첫째 단의 잡음 정합은 물론 각 단의 정합회로가 간단하도록 high pass 구조로 설계하였다. 바이어스 회로는 단일 능동회로로 구성하였고, 인가전압은 8V, 총 전류는 180mA이다. 이때, 첫째 단 PHEMT의 Vgs = -0.4V, Vds = 4V이고, 둘째 단 AH1의 Vds = 5V이다. 상업화가 가능하도록 설계 기준을 정하여 제작되었고, 측정 결과 이득은 20dB, NF는 1dB, 입력 VSWR은 1.14∼l.3dB, P1dB는 22.4dBm, gain flatness는 ±0.45dB로 상업용 저잡음 증폭기로 사용될 수 있다.

• 한국식품영양학회지
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• 제31권4호
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• pp.495-501
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• 2018

Ultraviolet B (UVB) exposure is a risk factor for skin damage resulting in oxidative stress, inflammation, and cell death. The purpose of this study was to investigate the physicochemical properties of Platycodon grandiflorum (PG) to improve its biological activities using a three-step steaming process. We investigated the protective effects of PG and steamed PG extracts on human dermal fibroblasts (HDFs) against UVB radiation-induced oxidative stress and inflammation as well as the underlying mechanisms. The antioxidant potential of the PG extracts was evaluated by measuring the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging activity. ABTS and DPPH were shown by the 0, 30, and 70% ethanol extracts of 2S-PG and 3S-PG ($IC_{50}$, 28~45 and $27{\sim}30{\mu}g/mL$, respectively). Treatment of UVB-irradiated cells with steamed PG ($25{\sim}400{\mu}g/mL$) did not affect their viability. The streamed PG extract suppressed UVB-induced generation of reactive oxygen species (ROS). In addition, streamed PG extract reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expression in UVB-irradiated HDF, regulating nuclear factor $(NF)-{\kappa}B$ expression. These findings suggest that steamed PG extract may be potentially effective against inflammation associated with UVB-induced oxidation stress.

• 대한기계학회논문집A
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• 제34권4호
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• pp.467-474
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• 2010

용접이음부의 신뢰성 확보는 구조물의 건전성과 내구성에 직접적인 영향을 미치기 때문에 가스용접 이음재의 피로설계기준(fatigue design criterion)을 정하기 위해서는 피로시험을 수행하여 ${\Delta}P$-Nf 관계를 이용하는 것이 일반적이다. 그러나 피로데이터를 장시간 획득하는 과정에서 여러 가지 변동인자에 의해서 피로데이터가 영향을 받기 때문에 피로데이터의 신뢰도가 떨어진다. 또한, 이음재의 재질 및 접합형태가 달라질 때마다, 각각의 경우에 대해서 새로운 피로시험이 요구됨으로 많은 시간과 비용이 소모된다. 따라서 이러한 문제점들을 개선하고 신뢰성 있는 설계를 하기 위해서 필렛 가스용접 이음재를 적용, 반복피로시험을 통한 데이터를 통계적으로 분석하여, 다양한 가스용접 이음재의 피로수명을 예측함과 동시에 실제 피로시험데이터와 비교 분석하여 예측된 수명의 신뢰도(reliability)와 신뢰구간(confidence interval)을 추정함으로서 새로운 피로설계기준 방법을 제시하고자 하였다.

• 생약학회지
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• 제43권3호
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• pp.217-223
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• 2012

In the present study, we investigated anti-inflammatory activity of artemisinic acid in HaCaT cells and RAW264.7 cells. Artemisinic acid showed inhibitory activity on macrophage-derived chemokines (MDC) expression, a factor related with atopic dermatitis (AD), in interferon (IFN)-${\gamma}$ and tumor necrosis factor (TNF)-${\alpha}$-stimulated HaCaT cells. In the study on action mechanism, pretreated artemisinic acid reduced the phosphorylation of STAT1 and p38 and the degradation of $I{\kappa}B$ by IFN-${\gamma}$ and TNF-${\alpha}$ stimulations. However, artemisinic acid didn't show the inhibitory activity on LPS-induced inflammatory mediators (NO, $PGE_2$, IL-6) in RAW264.7 cell. These results indicate that artemisinic acid inhibits IFN-${\gamma}$ and TNF-${\alpha}$-induced MDC expression through inhibition of signal factors, STAT1, NF-${\kappa}B$, and p38, in HaCaT keratinocytes.

• Natural Product Sciences
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• 제22권3호
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• pp.193-200
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• 2016

This study describes the anti-inflammatory, anti-oxidant, and melanogenesis inhibition activities of methanol extract and various organic solvent fractions of Arecae Pericarpium. We examined the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells, 1,1-diphenyl-2-picrylhydrazine (DPPH) scavenging activity, mushroom tyrosinase inhibition activity and melanin contents. The study showed that, among all tested fractions, methylene chloride fraction showed the strongest inhibition of LPS-induced NO production in RAW 264.7 cells ($IC_{50}$ value $8.89{\mu}g/mL$) and DPPH radical scavenging activity ($EC_{50}$ value $21.39{\mu}g/mL$). Methylene chloride and ethyl acetate fractions similarly inhibited mushroom tyrosinase activity. Methanol extract exhibited strongest reduction of melanin content in B16F10 melanoma cells. Based on the bioactivity assay results, methylene chloride and ethyl acetate fractions were further separated. Eight phenolic compounds were isolated, which are dimeric syringol (1), catechol (2), 4-hydroxybenzaldehyde (3), vanillin (4), 4-hydroxyacetophenone (5), apocynin (6), protocatechuic acid (7) and 4-hydroxybenzoic acid (8). Among the isolated compounds tested, catechol showed the strongest inhibition of LPS-induced NO production in RAW 264.7 cells. Catechol also showed the concentration-dependent NF-${\kappa}B$ inhibition activity. Arecae Pericarpium might have potentials to be developed as anti-inflammatory agent or dermatological product for skin-whitening agent.

• 한방재활의학과학회지
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• 제30권1호
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• pp.47-61
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• 2020

Objectives This study is carried out to investigate the effects of Lonicera japonica in wound-induced rats. Methods Rats were divided into 5 groups; normal (Nor), control (Veh), positive comparison (PC), Lonicera japonica 100 mg/kg (LL), Lonicera japonica 200 mg/kg (LH), each n=8. Total polyphenol and flavonoid were quantified. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging activation were measured. Reactive oxygen species (ROS) was measured in serum. Antioxidant factors and inflammatory factors were measured in skin tissue, and also hydroxyproline content. Skin tissue was analyzed by Hematoxylin & Eosin and Masson's trichrome staining method. Results Total polyphenol and flavonoid were 32.86±0.14 mg/g and 67.17±0.57 mg/g. The IC₅₀ values of DPPH and ABTS free radical scavenging activation were 26.69±1.50 ㎍/mL and 49.33±4.52 ㎍/mL. ROS was significantly lower in LL and LH groups. Nuclear factor-erythroid 2-related factor 2 (Nrf2) was significantly higher in LH group and higher in LL group but not significant. Superoxide dismutase 1 (SOD-1), catalase, and heme oxygenase 1 (HO-1) were significantly higher in LL and LH groups. Nuclear factor kappa-B p65 (NF-κBp65), phosphorylated iκBα (p-iκBα), cyclooxygenase 2 (COX-2), and tumor necrosis factor alpha (TNF-α) were significantly lower in LL and LH groups. Hydroxyproline was significantly higher in LL and LH groups. The histopathologic analysis showed that skin tissue had recovered further more in LL and LH groups than in Veh group. Conclusions These results suggest that Lonicera japonica has the anti-oxidant, anti-inflammatory and healing effects in wound-induced rats.