• 대한의생명과학회지
• /
• 제2권2호
• /
• pp.175-185
• /
• 1996

모든 진핵세포에 존재하며 세포의 성장 및 분화에 주로 관계되는 신호전달물질의 하나인 Mitogen-activated protein(MAP)kinase의 mitogen에 의한 핵내 활성화와 기질 인산화에 대해 알아보기 위해 본 실험을 수행하였다. P388세포를 10% fetal bovine serum이 첨가된 DMEM배지에 배양한 후, 혈청이 들어있지 않은 배지에서 24시간 더 배양하고 serum 및 PMA를 농도별로 처리하여 세포성 장을 위한 최적 농도를 확인한 결과 serum은 5-20% 농도에서 세포성장을 촉진시켰고 PMA는 실험한 모든 농도에서 세포성장을 거의 촉진시키지 못하는 경향을 확인하였다. 이어 P388 세포를 serum 및 PMA로 10 분간 활성화하여 파쇄한후 세포질분획과 핵분획으로 분리하여 각 분획을 10% gel 상에서 전기영동 하여 nitrocellulose paper에 옳긴 후 anti-ERKI antibody를 이용해 확인해본 결과 serum, PMA로 처리된 세포 모두에서 MAP kinase의 핵내 이동이 관찰되었으며 특히 세포질 내에 주로 존재하는 42, 44 Kd의 MAP kinase isoform중 42 Kd의 isoform이 주로 핵내로 이동되는 것이 관찰되었다. MAP kinase의 기질인산화 실험을 위해 serum으로 활성화시킨 세포를 파쇄하여 SP-sephadex C-50, Phenyl superose, Mono Q column의 순서로 chromatography를 시 행하여 MAP kinase를 부분분리 하였다. 이와 같이 얻은 MAP kinase를 가지고 면역 T세포에 존재하는 tyrosine kinase인 $p56^{lck}$ 의 N-terminal peptide로 구성된 GST-fusion protein에 대한 인산화를 확인하였다. 또한 세포에서 분리한 MAP kinase를 가지고 transcription factor의 하나인 c-Jun protein에 대한 인산화실험을 실시한 결과 MAP kinase에 의해 인산화 됨이 확인되었다. 이상의 결과를 통해 P388세포는 (1)세포 성장시 외부 신호를 G-protein-coupled receptor/protein kinase C/MAP kinase의 경로보다는 주로 tyrosine kinase receptor protein/Ras/MAP kinase의 경로를 이용하여 핵으로 전달하는 것으로 추측되 며 (2) mitogen의 처리로 활성화된 MAP kinase중 주로 42 Kd isoform이 핵내로 이동하고, 분리한 MAP kinase가 GST-fusion protein과 transcription factor인 c-Jun을 모두 인산화 시키는 결과로 보아 MAP kinase의 isoform에 따라 표적 compartment가 다르고 결과적으로 표적 기질에 차이가 있을지 모른다고 간접적으로 추론할 수 있다.

• 한국식품영양과학회지
• /
• 제45권9호
• /
• pp.1257-1264
• /
• 2016

개똥쑥은 예로부터 항암, 항바이러스 및 항균의 효능을 지니는 것으로 알려져 왔지만 작용 기작에 대한 내용이 많이 알려지지 않았다. 본 연구에서는 AGS 인체 위암 세포를 대상으로 개똥쑥 추출물(AAE)에 의한 apoptosis 효과와 신호경로 연구를 시행하였다. AAE의 암세포 성장에 미치는 영향을 확인하기 위하여 AGS cell에 AAE를 처리하고 MTT assay와 LDH assay를 수행한 결과 AAE 농도 의존적으로 나타난 세포 성장 억제가 세포 손상에 의한 것임을 확인하였다. 또한, AAE에 의한 암세포 증식 억제 효과가 apoptosis에 의한 것인지 확인하기 위하여 Hoechst 33342 staining과 Annexin V-PI staining을 수행한 결과, Hoechst 33342 staining에서 apoptotic body와 세포질 응축이 농도 의존적으로 증가하는 것을 확인하였고, Annexin V-PI staining에서 apoptotic cells의 변화가 농도 의존적으로 증가함을 확인하였다. Western blotting의 결과 AAE가 농도 의존적으로 세포 생장에 관여하는 신호 단백질인 p-Akt, p-TSC2, p-mTOR, p-GSK-$3{\beta}$의 발현이 감소함을 확인하였고, anti-apoptotic 단백질인 Bcl-2의 발현이 억제됨으로써 proapoptotic 단백질인 Bax, Bak의 발현이 증가하는 일련의 신호경로를 조절할 수 있다는 것을 확인하였다. 미토콘드리아 막 전위의 탈분극 유도를 확인하기 위한 JC-1 assay 수행 결과, AAE 농도 의존적으로 미토콘드리아 막 전위의 탈분극이 유도됨을 확인하였다. 탈분극에 의한 caspase 활성을 확인하기 위해 caspase-3/7 activity assay를 수행한 결과, AAE 농도 의존적으로 caspase activity 증가를 확인하였다. 또한, apoptosis가 일어나는 일련의 신호경로를 확인하기 위해 apoptosis 상위 단백질인 Akt, mTOR, GSK-$3{\beta}$의 활성을 억제하는 LY294002, Rapamycin, BIO를 각각 AGS cell에 처리하고 세포증식에 미치는 영향과 신호 단백질의 발현 양상을 알아보기 위해 MTT assay, LDH assay, western blotting을 수행하였다. 그 결과 AAE와 LY294002, Rapamycin 처리군에서 세포증식 억제와 LDH 방출량 증가뿐만 아니라 세포 생장 신호 단백질인 p-mTOR, p-TSC2, p-Akt, p-GSK-$3{\beta}$의 발현이 감소하는 것을 확인하였고, Bcl-2의 발현이 억제됨으로써 Bax와 Bak의 발현을 증가시키는 신호경로를 조절할 수 있다는 것을 확인하였다. 따라서 AGS cell에 개똥쑥 추출물을 처리하였을 때 유도되는 apoptosis 효과는 Akt/mTOR/GSK-$3{\beta}$ 경로 활성 억제를 통해 Bcl-2 발현이 감소함에 따라 Bax, Bak를 활성화해 세포질로의 cytochrome C 유리에 따른 caspase 활성으로 이루어진다는 것을 알 수 있었다.

• 생명과학회지
• /
• 제29권4호
• /
• pp.402-409
• /
• 2019

생삼을 쪄서 건조시킨 홍삼은 전통적으로 사용되고 있는 약재로서 면역, 내분비 및 중추신경계 작용을 증진시키며 염증을 억제하는 효과가 있는 것으로 알려져 있다. 본 연구에서는 그람 양성균의 세포벽 성분인 lipoteichoic acid (LTA)에 의한 염증반응에 홍삼추출액(RGE)이 항염증 효과를 가지는지 관찰하고 그 작용 기전을 연구하였다. BV-2 소교세포에서 RGE는 세포에 독성을 유도하지 않으면서 LTA로 인한 nitric oxide (NO)의 생성과 inducible nitric oxide synthase (iNOS) 발현을 억제하였으며, NF-kB p65의 핵으로의 이동과 IkB-a의 분해 또한 억제하였다. 한편, RGE는 농도의존적으로 heme oxygenase-1 (HO-1)의 발현을 유도하였으며, HO-1 siRNA를 처리했을 때는 RGE가 iNOS의 발현을 억제하지 못하였다. RGE는 HO-1의 발현에 관여하는 전사인자인 nuclear factor E2-related factor 2 (Nrf2)를 핵으로 이동을 촉진시켰다. 또한 RGE에 의한 HO-1의 발현은 phosphatidylinositol-3-kinase(PI-3K) 및 MAPK 억제제에 의해 감소되었으며, RGE가 Akt와 ERK, p38, JNK의 인산화를 유도하였다. 이상의 결과를 종합해보면, RGE는 PI-3K/Akt 및 ERK, p38, JNK 신호전달과정을 통해 HO-1의 발현을 유도함으로써 NO와 같은 염증매개물질의 생성을 억제한다는 것을 알 수 있다. 그러므로 홍삼추출액은 그람 양성균에 의한 신경염증과 염증관련 신경계 질환의 치료제로서 사용될 수 있을 것이라 사료된다.

• Archives of Pharmacal Research
• /
• 제28권3호
• /
• pp.305-310
• /
• 2005

It has been suggested that nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) may act as a mediator of cytokine-induced effects on bone turn-over. NO is also recognized as an important factor in bone remodeling, i.e., participating in osteoblast apoptosis in an arthritic joint. The components of Agastache rugosa are known to have many pharmacological activities. In the present study, we investigated the effects of Agastache rugosa leaf extract (ELAR) on NO production and the iNOS expression in ROS 17/2.8 cells activated by a mixture of inflammatory cytokines including TNF-$alpha$ and IL-1$\beta$. A preincubation with ELAR significantly and concentration-dependently reduced the expression of iNOS protein in ROS 17/2.8 cells activated with the cytokine mixture. Consequently, the NO production was also significantly reduced by ELAR with an IC$_{50}$ of 0.75 mg/mL. The inhibitory mechanism of iNOS induction by ELAR prevented the activation and translocation of NF-$\kappa$B (p65) to the nucleus from the cytosol fraction. Furthermore, ELAR concentration-dependently reduced the cellular toxicity induced by sodium nitroprusside, an NO-donor. These results suggest that ELAR may be beneficial in NO-mediated inflammatory conditions such as osteoporosis.

• 동의생리병리학회지
• /
• 제23권5호
• /
• pp.986-992
• /
• 2009

Type I interferons (IFNs) are critical mediators of the innate immune system to defend viral infection. Interferon regulatory factor (IRF) and signal transducer and activator of transcription (STAT) play critical roles in type I IFN production in response to viral infection. Luteolin is natural polyphenolic compounds that have anti-inflammatory, cytoprotective and anti-carcinogenic effects. However, the mechanism of action and impact of luteolin on innate immunity is still unknown. In this study, we examined the effects of luteolin on the lipopolysacchride (LPS)-induced inflammatory responses. Luteolin inhibited Type I IFNs expression of mRNA and increased interleukin(IL)-10 expression of mRNA. Next, we examined the protective effects of IL-10 using IL-10 neutralizing antibody (IL-10NA). Blockade of IL-10 action didn't cause a significant reduction of Type I IFNs than LPS-induced luteolin pretreatment. Pretreatment of luteolin inhibited the level of IRF-1, and IRF-7 mRNA and the nuclear translocation of IRF-3. Also, luteolin reduced the activation of STAT - 1, 3. Theses results suggest that luteolin inhibits LPS-induced the production of Type I IFNS by both IRFs and STATs not IL-10 and may be a beneficial drug for the treatment of inflammatory disease.

• Journal of Chest Surgery
• /
• 제38권11호
• /
• pp.776-779
• /
• 2005

대동맥과 주폐동맥 사이의 좌관상동맥동에서 이상기시하는 우관상동맥은 급사, 실신, 부정맥, 심근허혈을 일으킬 수 있다. 이러한 기형에서 관상동맥의 혈류에 제한을 주는 기전은 확실하지 않으며, 관상동맥우회로술이나 관상동맥의 이식, 폐동맥의 전위, Unroofing 술식과 같은 여러 가지의 수술적 치료방법이 보고되고 있다. 저자들은 Unroofing 술식을 이용하여 대동맥과 주폐동맥 사이의 '좌관상동맥동에서 이상기시하는 우관상동맥을 교정하여 보고하는 바이다

• Journal of Ginseng Research
• /
• 제46권1호
• /
• pp.156-166
• /
• 2022

Background: Panax ginseng Meyer (P. ginseng), a herb distributed in Korea, China and Japan, exerts benefits on diverse inflammatory conditions. However, the underlying mechanism and active ingredients remains largely unclear. Herein, we aimed to explore the active ingredients of P. ginseng against inflammation and elucidate underlying mechanisms. Methods: Inflammation model was constructed by lipopolysaccharide (LPS) in C57BL/6 mice and RAW264.7 macrophages. Molecular docking, molecular dynamics, surface plasmon resonance imaging (SPRi) and immunofluorescence were utilized to predict active component. Results: P. ginseng significantly inhibited LPS-induced lung injury and the expression of proinflammatory factors, including TNF-α, IL-6 and IL-1β. Additionally, P. ginseng blocked fluorescencelabeled LPS (LPS488) binding to the membranes of RAW264.7 macrophages, the phosphorylation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). Furthermore, molecular docking demonstrated that ginsenoside Ro (GRo) docked into the LPS binding site of toll like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD2) complex. Molecular dynamic simulations showed that the MD2-GRo binding conformation was stable. SPRi demonstrated an excellent interaction between TLR4/ MD2 complex and GRo (K_D value of 1.16 × 10^-9 M). GRo significantly inhibited LPS488 binding to cell membranes. Further studies showed that GRo markedly suppressed LPS-triggered lung injury, the transcription and secretion levels of TNF-α, IL-6 and IL-1β. Moreover, the phosphorylation of NF-κB and MAPKs as well as the p65 subunit nuclear translocation were inhibited by GRo dose-dependently. Conclusion: Our results suggest that GRo exerts anti-inflammation actions by direct inhibition of TLR4 signaling pathway.

• Journal of Ginseng Research
• /
• 제47권3호
• /
• pp.458-468
• /
• 2023

Background: As a complication of Type II Diabetes Mellitus (T2DM), the etiology, pathogenesis, and treatment of cognitive dysfunction are still undefined. Recent studies demonstrated that Ginsenoside Rg1 (Rg1) has promising neuroprotective properties, but the effect and mechanism in diabetes-associated cognitive dysfunction (DACD) deserve further investigation. Methods: After establishing the T2DM model with a high-fat diet and STZ intraperitoneal injection, Rg1 was given for 8 weeks. The behavior alterations and neuronal lesions were judged using the open field test (OFT) and Morris water maze (MWM), as well as HE and Nissl staining. The protein or mRNA changes of NOX2, p-PLC, TRPC6, CN, NFAT1, APP, BACE1, NCSTN, and Ab1-42 were investigated by immunoblot, immunofluorescence or qPCR. Commercial kits were used to evaluate the levels of IP3, DAG, and calcium ion (Ca²⁺) in brain tissues. Results: Rg1 therapy improved memory impairment and neuronal injury, decreased ROS, IP3, and DAG levels to revert Ca²⁺ overload, downregulated the expressions of p-PLC, TRPC6, CN, and NFAT1 nuclear translocation, and alleviated Aβ deposition in T2DM mice. In addition, Rg1 therapy elevated the expression of PSD95 and SYN in T2DM mice, which in turn improved synaptic dysfunction. Conclusions: Rg1 therapy may improve neuronal injury and DACD via mediating PLC-CN-NFAT1 signal pathway to reduce Aβ generation in T2DM mice.

• The Korean Journal of Physiology and Pharmacology
• /
• 제13권6호
• /
• pp.475-482
• /
• 2009

Rifampicin is a macrocyclic antibiotic which is used extensively for treatment against Mycobacterium tuberculosis and other mycobacterial infections. Recently, a number of studies have focused on the immune-regulatory effects of rifampicin. Therefore, we hypothesized that rifampicin may influence the TLR2 expression in LPS-activated RAW 264.7 cells. In this study, we determined that rifampicin suppresses LPS-induced TLR2 mRNA expression. The down-regulation of TLR2 expression coincided with decreased production of TNF-$\alpha$ Since NF-${\kappa}B$ is a major transcription factor that regulates genes for TLR2 and TNF-$\alpha$, we examined the effect of rifampicin on the LPS-induced NF-${\kappa}B$ activation. Rifampicin inhibited NF-${\kappa}B$ DNA-binding activity in LPS-activated RAW 264.7 cells, while it did not affect IKK$\alpha/\beta$ activity. However, rifampicin slightly inhibited the nuclear translocation of NF-${\kappa}B$ p65. In addition, rifampicin increased physical interaction between pregnane X receptor, a receptor for rifampicin, and NF-${\kappa}B$ p65, suggesting pregnane X receptor interferes with NF-${\kappa}B$ binding to DNA. Taken together, our results demonstrate that rifampicin inhibits LPS-induced TLR2 expression, at least in part, via the suppression of NF-${\kappa}B$ DNA-binding activity in RAW 264.7 cells. Thus, the present results suggest that the rifampicin-mediated inhibition of TLR2 via the suppression of NF-${\kappa}B$ DNA-binding activity may be a novel mechanism of the immune-suppressive effects of rifampicin.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제27권2호
• /
• pp.129-134
• /
• 2001

Since NNK is one of the most abundant tobacco-specific alkaloids and a strong carcinogenic nitrosamine, it has been used for evaluating a potential of carcinogenicity in the animal models. The present study has attempted to examine the potential of carcinogenicity of NNK in human epithelial cells, from which the cell type the most of cancers including oral cancer and nasal cavity cancer are originated. The cellular model used for the study is a human keratinocyte cell system immortalized by Ad12-SV40 hybrid virus. The cellular system has successfully been used for the carcinogenicity studies because of its limitless life span, epithelial morphology and nontumorigenicity. When cells were treated with a variety of NNK concentrations, levels of saturation density and soft agar colony formation were increased in a dose-dependent fashion. Colonies of large cell aggregates were above 5 at the higher doses. The results indicate that exposure of human cells with NNK induced loss of contact inhibition and increases of anchorage independence and cellular adhesion, which are typical characteristics of the neoplatically transformed cells. When cells were exposed with 100uM NNK for 2hr, mRNA levels of IL-1 and PAI-2 were increased in a dose-dependent manner, but expression of TGF- 1 was not affected. While expression of growth regulatory factors were altered with a short-term exposure, there was no alteration of these factors in the NNK-transformed cells. However, mRNA levels of fibronectin were increased both in the short-term treatment and in the transformation. The results suggest that altered expression of extracellular matrix such as fibronectin following short-term exposure might be fixed in the genome and these altered properties be continuously transfered throughout the cell division. Western blot analysis showed a translocation of PKC- from cytosolic fraction to the particulate fraction, indicating a possible role of NNK in the signal transduction pathway. The present study provided an evidence that NNK in the smoking may be associated with epithelial origin cancer such as oral and nasal cavity cancers. In addition, this study suggested that altered expression of extracellular matrix and PKC may play an important role in the carcinogenic mechanism of NNK.