• Radiation Oncology Journal
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• 제21권3호
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• pp.227-237
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• 2003

목적: 만성 골수성 백혈병 세포인 K562 세포주는 방사선 및 다양한 항암제에 대한 apoptosis에 저항성을 가진다. 지난 연구에서 K562 세포는 방사선에 대하여 내성반응을 보이며, 세포내 PTK의 작용을 억제하고자 방사선 조사와 함께 투여한 herbimycin A (HMA)에 의하여 방사선에 대한 apoptosis와 같은 감수성반응이 유도되는 반면, genistein에 의하여 방사선에 대한 apoptosis 반응이 저해됨을 확인하였다. 본 연구에서는 타이로신 인산화효소 억제에 의한 K562 세포의 방사선 반응변화를 조절하는 신호전달경로를 조사하였다. 대상 및 방법: K562 세포를 지수증식기의 세포들만 선택하여 실험에 이용하였다. 방사선조사는 6 MeV 선형가속기(Clinac 1800C, Varian)를 이 용하여 $200\~300$ cGy/min 선량률로 $0.5\~12 $ Gy를 균일하게 조사하였다. HMA와 genistein은 각각 $0.25/muM,\;25\muM$을 방사선 조사 후 즉시 투여하였다. 실험에서 신호전달 경로로 abl kinase, MAPK family, NF-kB, c-fos, c-myc, thymidine kinase1 (TK1) 등에서의 단백질 또는 유전자 발현 및 활성을 조사하였다. 또한 약제 투여에 따른 유전자 발현차이(differential gene expression)를 조사하였다. 결과: Abl kinase의 발현 및 활성 변화를 조사하였으나 PTK 저해제에 의한 방사선 유도 세포사의 변화와의 연관성을 찾을 수 없었다. 세포 생존 및 사멸의 신호전달체계에서 주요 조절과정인 MAPK family의 관여 여부 확인에서 방사선으로 인한 SAPK/JNK의 활성화의 유도가 관찰되었으나, PTK 저해제에 따른 변화는 없었으며, 또한 MAPK/ERK와 p38 MAPK 활성은 모든 조건에서 변함 없이 일정하였다. 전사인자 활성화에 대한 조사에서 방사선 조사와 함께 genistein을 투여한 경우에 NF-kB활성이 증가하였다. 유전자 발현 차이의 조사에서 genistein 투여에 의한 TK 1 유전자 발현 및 단백질 활성이 증가하였다. 결론: PTK 억제에 의한 K562 세포의 방사선에 대한 반응 변화는 bcrabl kinase 활성과는 무관하게 진행되며, MAPK family 경로 외의 다른 경로를 통한 전사인자 활성화 과정이 연관되어 있음을 확인하였다.

• Journal of Applied Biological Chemistry
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• 제61권2호
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• pp.205-211
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• 2018

리바우디오사이드 A는 Stevia rebaudiana Bertoni에서 분리된 천연감미료로 널리 알려진 스테비올배당체 중 하나이다. 최근 연구에서 LPS 자극에 의해 활성화된 RAW264.7 마우스 대식 세포에서 리바우디오사이드 A가 인터루킨-$1{\alpha}/1{\beta}$ 같은 염증성 사이토카인 분비를 억제하는 기능이 확인되었다. 그러나 LPS처리 시 리바우디오사이드 A의 항염 활성에 대한염증 억제기작은 정확히 제시하지 못하였다. 따라서 본 연구에서는 리바우디오사이드 A의 LPS 신호전달 메카니즘에서의 항염증 효능을 단백질 수준에서 규명하고자 하였다. NO 생성에 관여하는 iNOS 단백질 발현양을 분석한 결과 리바우디오사이드 A의 $250{\mu}M$ 처리군에서 농도 의존적으로 단백질 발현이 감소하는 것을 확인하였다. 또한 염증 신호에 의한 대표적 핵 전사 인자인 $NF{\kappa}B$의 mRNA 발현량 분석 결과에서도 LPS 처리군에 비해 그 발현양이 감소하였다. 또한 세포질에 존재하는 $NF-{\kappa}B$와 $I-{\kappa}B$ 복합체는 LPS신호에 의한 $I-{\kappa}B$의 인산화 및 ubiquitination로 인해 $NF-{\kappa}B$가 이탈되기 때문에, 리바우디오사이드 A에 의한 $pNF-{\kappa}B$, $pI-{\kappa}B$의 단백질 발현을 비교 분석한 결과 $NF-{\kappa}B$ 단백질의 인산화가 농도 의존적으로 감소하였고, $I-{\kappa}B$의 인산화 또한 저해되는 것을 확인 하였다. 최종적으로 리바우디오사이드 A는 LPS처리 조건에서 MAPK중 특이적으로 extracellular signal-regulated kinase (ERK1/2)의 인산화를 농도 의존 방식으로 감소시킴으로써 $NF-{\kappa}B$ 조절 기작에 관여함을 알 수 있었다. 따라서 본 연구 결과들을 통해 우리는 리바우디오사이드 A가 RAW264.7 세포에서 LPS에 의해 활성화 되는 MAPK 및 $NF{\kappa}B$의 발현 억제를 통해 염증이 억제될 수 있음을 확인하였다.

• BMB Reports
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• 제56권6호
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• pp.359-364
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• 2023

KAI1/CD82, a membrane tetraspanin protein, can prevent various cancers and retinal disorders through its anti-angiogenic and anti-metastatic capacity. However, little is known about its anti-inflammatory effect and molecular mechanism. Therefore, the present study aimed to inLPSvestigate effect of a recombinant protein of the large extracellular domain of human KAI1 (Gly 111-Leu 228, rhKAI1) on lipopolysaccharides (LPS)-stimulated RAW264.7 macrophage-like cells and mouse bone marrow-derived macrophages (BMDM) and to identify its underlying mechanism. Our data showed that rhKAI1 suppressed expression levels of classically macrophages (M1) phenotype-related surface markers F4/80+CD86+ in LPS-stimulated BMDM and RAW264.7 cells. In addition, LPS markedly increased mRNA expression and release levels of pro-inflammatory cytokines and mediators such as interleukin (IL)-1β, IL-6, tumor necrosis factor-α, cyclooxygenase-2, nitric oxide and prostaglandin E2, whereas these increases were substantially down-regulated by rhKAI1. Furthermore, LPS strongly increased expression of NF-κB p65 in the nuclei and phosphorylation of ERK, JNK, and p38 MAPK. However, nuclear translocation of NF-κB p65 and phosphorylation of JNK were greatly reversed in the presence of rhKAI1. Especially, rhKAI1 markedly suppressed expression of toll-like receptor (TLR4) and prevented binding of LPS with TLR4 through molecular docking predict analysis. Importantly, Glu 214 of rhKAI1 residue strongly interacted with Lys 360 of TLR4 residue, with a binding distance of 2.9 Å. Taken together, these findings suggest that rhKAI1 has an anti-inflammatory effect on LPS-polarized macrophages by interacting with TLR4 and down-regulating the JNK/NF-κB signaling pathway.

• 생명과학회지
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• 제17권10호
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• pp.1447-1451
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• 2007

해양생물 유래 항암활성을 가지는 천연물의 탐색과정에서 해면동물에서 유래된 PTX-2는 p53 결손 암세포에서 세포독성 효과가 높은 것으로 보고된 바 있다. 본 연구에서는 인체 간암세포 모델을 이용하여 PTX-2의 효능을 조사한 결과는 p53 결손 Hep3B 세포에서 p53 정상 HepG2에 비하여 항암활성이 매우 높았으며, 이는 apoptosis 유발과 연관성이 있음을 확인하였다. PTX-2에 의한 Hep3B 세포의 apoptosis 유발은 DFF family의 발현 변화, pro-apoptotic Bax 및 Bcl-xS 단백질의 발현 증가, caspases (-3, -8 및 -9)의 활성화 등이 관여함을 알 수 있었다. PTX-2는 또한 Hep3B 세포에서 AKT 및 ERK1/2의 활성화를 유도하였으며, caspase-3, AKT 및 ERK1/2의 특이적 저해제에 의하여 PTX-2에 의한 세포증식 억제 효능이 유의적으로 감소되었다. 본 연구는 PTX-2에 의한 Hep3B 세포에서의 apoptosis 유도에 AKT 및 ERK1/2 신호 전달 경로가 중요한 역할을 하고 있음을 보여주는 결과이다.

• Journal of Microbiology and Biotechnology
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• 제27권10호
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• pp.1885-1891
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• 2017

In this study, we evaluated the inhibitory effect of a rice bran mixture extract (RBE) on Brucella abortus pathogenesis in professional (RAW 264.7) and nonprofessional (HeLa) phagocytes. We fermented the rice bran mixture and then extracted it with 50% ethanol followed by gas chromatography-mass spectrometry to identify the components in RBE. Our results clearly showed that RBE caused a significant reduction in the adherence of B. abortus in both cell lines. Furthermore, analysis of phagocytic signaling proteins by western blot assay revealed that RBE pretreatment resulted in inhibition of phosphorylation of JNK, ERK, and p38, leading to decline of internalization compared with the controls. Additionally, the intensity of F-actin observed by fluorescence microscopy and FACS was remarkably reduced in RBE-pretreated cells compared with control cells. However, the intracellular replication of B. abortus within phagocytes was not affected by RBE. Taken together, these findings suggest that the phagocytic receptor blocking and suppressive effects of RBE on the MAPK-linked phagocytic signaling pathway could negatively affect the invasion of B. abortus into phagocytes.

• 대한한의학방제학회지
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• 제25권4호
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• pp.471-481
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• 2017

Objectives : Noemyeong-san (NMS) is a novel herbal prescription composed of five oriental medicinal herbs including Prunellae Spica, Betulae Cortex, Foeniculi Fructus, Asiasari Radix, and Clematidis Radix for treating Alzheimer's disease. In the present study, we investigated the effects and molecular mechanisms of NMS on BV2 microglia to evaluate the potential action of this formula for preventing or treating neurodegenerative disease such as Alzheimer's disease. Methods : To determine the cytotoxicity of NMS on BV2 microglia, the MTT assay was performed. The effects of NMS on lipopolysaccharide (LPS)-stimulated BV2 microglia were determined with a nitric oxide (NO) assay and western blots for inflammatory mediator-related proteins, mitogen activated protein kinases (MAPKs), nuclear factor kappa B (NF-${\kappa}B$) pathway-related proteins, and heme oxygenase-1 (HO-1). Result : NMS inhibited induction of iNOS and COX-2 as well as NO production without affecting the cell viability in LPS-stimulated BV2 microglia. NMS also suppressed activation of ERK and p38 MAPK among main kinases of MAPKs as well as NF-${\kappa}B$ by LPS stimulation. Furthermore, NMS dose-dependently induced the expression of HO-1 and the inhibitory effect of NMS on the production of NO were blocked by pretreatment with an HO-1 inhibitor, Snpp. Conclusions : These results demonstrate that NMS has potent anti-neuroinflammatory effect on the LPS-stimulated microglia. These findings provide evidences for NMS to be considered as a new prescription for preventing or treating neurodegenerative disease such as Alzheimer's disease.

• Journal of Microbiology and Biotechnology
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• 제30권10호
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• pp.1567-1573
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• 2020

Ultraviolet (UV) is one of the major factors harmful to skin health. Irradiation with ultraviolet accelerates the decline of skin function, causing the skin to have deep wrinkles, dryness, decreased procollagen production, and degradation of collagen. Novel materials are needed to prevent the aging of the skin by blocking the effects of UV. Safflower seed oil (Charthamus tinctorius L., SSO) contains significantly high levels of unsaturated fatty acids and phytochemicals. SSO has been traditionally used in China, Japan, and Korea to improve skin and hair. Our objective in this study was to determine the effect of SSO and its active compound acacetin on UVB-induced skin photoaging in HaCaT cells and human dermal fibroblasts (HDF). SSO inhibited UVB-induced matrix metalloproteinase-1 (MMP-1) at both protein and mRNA levels in HaCaT cells and HDF. MMP-1 is known to play important roles in collagen degradation and wrinkle formation. Acacetin, a type of flavonoid, is present in SSO. Similar to SSO, acacetin also inhibited UVB-induced MMP-1 protein and mRNA levels in HaCaT cells and HDF. MMP-1 mRNA is primarily regulated by the mitogen-activated kinase (MAPK) signaling pathway. Acacetin regulated the phosphorylation of JNK1/2 and c-jun, but did not inhibit the phosphorylation of ERK1/2, p38 and AKT. Taken together, these results indicate that SSO and its active compound acacetin can prevent UVB-induced MMP-1 expression, which leads to skin photoaging, and may therefore have therapeutic potential as an anti-wrinkle agent to improve skin health.

• International Journal of Oral Biology
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• 제33권2호
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• pp.51-58
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• 2008

A mutation of UNCL, an inner nuclear membrane RNAbinding protein, has been found to eliminate mechanotransduction in Drosophila. UNCL is expressed in human periodontal tissue including in periodontal ligament (PDL) fibroblasts. However, it is unclear how a mechanical stimulus is translated into cellular responses in PDL fibroblasts. The aim of this study was to evaluate the effect of UNCl on mechanical stress related genes in PDL fibroblasts in response to mechanical stress. The mRNA of TGF-$\beta$, COX-2, and MMP-2 was up-regulated after UNCL inactivation in PDL fibroblasts under the compression force. Under the tensile force, inactivation of UNCL decreased the expression of Biglycan, RANKL, MMP-2, and TIMP-2 mRNAs while it increased the expression of TIMP-1. p38-MAPK was expressed in PDL fibroblasts under compression forces whereas phospho-ERK1/2, p65-NFkB, and c-fos were expressed under tension forces. The expression and phosphorylation of the mechanical stress related genes, kinases, and transcription factors were changed according to the types of stress. Furthermore, most of them were regulated by the inactivation of UNCL. This suggests that UNCL is involved in the regulation of mechanical stress related genes through the signaling pathway in PDL fibroblasts.

• BMB Reports
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• 제53권11호
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• pp.594-599
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• 2020

Lin28a has diverse functions including regulation of cancer, reprogramming and regeneration, but whether it promotes injury or is a protective reaction to renal injury is unknown. We studied how Lin28a acts in unilateral ureteral obstruction (UUO)-induced renal fibrosis following unilateral ureteral obstruction, in a mouse model. We further defined the role of Lin28a in transforming growth factor (TGF)-signaling pathways in renal fibrosis through in vitro study using human tubular epithelium-like HK-2 cells. In the mouse unilateral ureteral obstruction model, obstruction markedly decreased the expression of Lin28a, increased the expression of renal fibrotic markers such as type I collagen, α-SMA, vimentin and fibronectin. In TGF-β-stimulated HK-2 cells, the expression of Lin28a was reduced and the expression of renal fibrotic markers such as type I collagen, α-SMA, vimentin and fibronectin was increased. Adenovirus-mediated overexpression of Lin28a inhibited the expression of TGF-β-stimulated type I collagen, α-SMA, vimentin and fibronectin. Lin28a inhibited TGF-β-stimulated SMAD3 activity, via inhibition of SMAD3 phosphorylation, but not the MAPK pathway ERK, JNK or p38. Lin28a attenuates renal fibrosis in obstructive nephropathy, making its mechanism a possible therapeutic target for chronic kidney disease.

• Biomolecules & Therapeutics
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• 제21권6호
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• pp.435-441
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• 2013

Emodin, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, has several beneficial pharmacologic effects, which include anti-cancer, anti-diabetic, and anti-inflammatory activities. In this study, the authors examined the effect of emodin on the production of proinflammatory cytokines, such as, tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the mechanism responsible for the regulation of pro-inflammatory cytokine production by emodin, the authors assessed its effects on the activations of transcriptional factor nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and mitogen-activated protein kinases (MAPKs). Emodin attenuated the nuclear translocation of (NF)-${\kappa}B$ p65 and its DNA-binding activity by reducing the phosphorylation and degradation of $I{\kappa}B{\alpha}$ and the phosphorylation of $I{\kappa}B$ kinase B (IKK). Furthermore, emodin dose-dependently attenuated the phosphorylations of MAPKs, such as, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase, and the stress-activated protein kinases (SAPK)/c-Jun-N-terminal kinase (JNK). Taken together, the findings of this study suggest that the anti-inflammatory effects of emodin on PMA plus A23187-stimulated BMMCs are mediated via the inhibition of NF-${\kappa}B$ activation and of the MAPK pathway.