• The Korean Journal of Physiology and Pharmacology
• /
• 제26권6호
• /
• pp.427-438
• /
• 2022

Pyroptosis, a form of cell death associated with inflammation, is known to be involved in diabetic nephropathy (DN), and discoid domain receptor 1 (DDR1), an inflammatory regulatory protein, is reported to be associated with diabetes. However, the mechanism underlying DDR1 regulation and pyroptosis in DN remains unknown. We aimed to investigate the effect of DDR1 on renal tubular epithelial cell pyroptosis and the mechanism underlying DN. In this study, we used high glucose (HG)-treated HK-2 cells and rats with a single intraperitoneal injection of streptozotocin as DN models. Subsequently, the expression of pyroptosis-related proteins (cleaved caspase-1, GSDMD-N, Interleukin-1β [IL-1β], and interleukin-18 [IL-18]), DDR1, phosphorylated NF-κB (p-NF-κB), and NLR family pyrin domain-containing 3 (NLRP3) inflammasomes were determined through Western blotting. IL-1β and IL-18 levels were determined using ELISA. The rate of pyroptosis was assessed by propidium iodide (PI) staining. The results revealed upregulated expression of pyroptosisrelated proteins and increased concentration of IL-1β and IL-18, accompanied by DDR1, p-NF-κB, and NLRP3 upregulation in DN rat kidney tissues and HG-treated HK-2 cells. Moreover, DDR1 knockdown in the background of HG treatment resulted in inhibited expression of pyroptosis-related proteins and attenuation of IL-1β and IL-18 production and PI-positive cell frequency via the NF-κB/NLRP3 pathway in HK-2 cells. However, NLRP3 overexpression reversed the effect of DDR1 knockdown on pyroptosis. In conclusion, we demonstrated that DDR1 may be associated with pyroptosis, and DDR1 knockdown inhibited HG-induced renal tubular epithelial cell pyroptosis. The NF-κB/NLRP3 pathway is probably involved in the underlying mechanism of these findings.

• 생명과학회지
• /
• 제18권3호
• /
• pp.336-343
• /
• 2008

본 연구에서는 인체전립선 상피세포인 267B1 세포에서 HDAC 저해제인 TSA에 의한 증식억제가 apoptosis 유도에 의한 것임을 제시하였다. 이러한 TSA에 의한 267B1 세포의 apoptosis에는 c-IAP-1 및 c-IAP-2와 같은 IAP family의 발현감소가 동반되었으나 Bax 및 Bcl-2와 같은 Bcl-2 family의 발현에는 큰 변화가 없었다. 그리고 TSA에 의한 267Bl 세포의 apoptosis는 caspase의 활성에 의한 표적 단백질들의 분해와 연관성이 있었다. 또한 TSA에 의한 apoptosis 유도에서 $NF-{\kappa}B$의 활성이 증가된다는 것을 세포질에서 $NF-{\kappa}B$의 핵 내로의 이동에 따른 전사활성의 증가 현상에 의한 것임을 다양한 방법으로 제시하였다. 본 연구의 결과는 TSA와 같은 HDAC 저해제에 의한 apoptosis 유도에는 $NF-{\kappa}B$의 활성 증가가 동반될 수 있음을 보여주는 결과로서 HDAC 저해제의 항암활성에 대한 $NF-{\kappa}B$의 새로운 역할 가능성을 제시하여 주는 것으로서 이에 관한 추가적인 연구의 필요성을 제시하였다.

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

• Natural Product Sciences
• /
• 제21권4호
• /
• pp.240-247
• /
• 2015

Viridicatol (1) has previously been isolated from the extract of the marine-derived fungus Penicillium sp. SF-5295. In the course of further biological evaluation of this quinolone alkaloid, anti-inflammatory effect of 1 in RAW264.7 and BV2 cells stimulated with lipopolysaccharide (LPS) was observed. In this study, our data indicated that 1 suppressed the expression of well-known pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and consequently inhibited the production of iNOS-derived nitric oxide (NO) and COX-2-derived prostaglandin E2 ($PGE_2$) in LPS stimulated RAW264.7 and BV2 cells. Compound 1 also reduced mRNA expression of pro-inflammatory cytokines such as $interleukin-1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6), and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$). In the further evaluation of the mechanisms of these anti-inflammatory effects, 1 was shown to inhibit nuclear factor-kappa B ($NF-{\kappa}B$) pathway in LPS-stimulated RAW264.7 and BV2 cells. Compound 1 blocked the phosphorylation and degradation of inhibitor kappa B $(I{\kappa}B)-{\alpha}$ in the cytoplasm, and suppressed the translocation of $NF-{\kappa}B$ p65 and p50 heterodimer in nucleus. In addition, viridicatol (1) attenuated the DNA-binding activity of $NF-{\kappa}B$ in LPS-stimulated RAW264.7 and BV2 cells.

• Korean Journal of Acupuncture
• /
• 제37권2호
• /
• pp.63-75
• /
• 2020

Objectives : Osteoporosis is the most common bone disease and osteoporosis fracture is the leading cause of decreased life. Bisphosphonate and selective estrogen receptor modulators are the best choice of treatment for osteoporosis. However, when used for a long time, they increase the probability of side effect such as osteonecrosis of the jaw. Thus, it is crucial to develop alternative medicine to treat osteoporosis. Gentianae Macrophyllae Radix, a herbal medicine, is mainly to treat rheumatoid arthritis. However, the effect of the water extract of Gentianae Macrophyllae Radix (w-GM) on osteoporosis has not been investigated. Thus, we examine whether w-GM can inhibit osteoclast differentiation and bone resorption on receptor activator of nuclear factor kappa-B (NF-κB) ligand (RANKL)-treated RAW 264.7 cells. In this study, RAW 264.7 cells were used as an osteoclast differentiation model by treating them with RANKL. Methods : RAW 264.7 cells were used to determine the effect of w-GM on osteoclast differentiation and bone resorption. The number of tartrate-resistant acid phosphatase (TRAP)-positive cells, TRAP activity and pit formation assay were examined. In addition, protein expressions were measured by western blot and mRNA expressions were analyzed by reverse transcription polymerase chain reaction. Results : Treatment with w-GM inhibited the number of TRAP-positive cells, TRAP activity and pit area. In addition, w-GM decreased protein expression such as mitogen-activated protein kinase, NF-κB, c-Fos and nuclear factor of activated T-cells cytoplasmic 1 (NFATc1). It also inhibited the mRNA levels such as c-Fos, NFATc1, TRAP, NF-κB, calcitonin receptor and cathepsin K in RANKL-treated RAW 264.7 cells. Conclusions : These results suggest that w-GM has inhibitory effects via osteoclast differentiation, thus it could be a new medication for osteoporosis.

• 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.

• 생명과학회지
• /
• 제33권2호
• /
• pp.176-182
• /
• 2023

석곡의 줄기는 전통 동양의학에서 위를 보하고, 진액을 보충하며, 열을 내리는 것에 사용되어 왔다. 본 연구에서는 RBL-2H3 세포에서 비만세포 탈과립과 TNF-α, IL-4, histidine decarboxylase (HDC) 발현에 미치는 석곡 열수추출물(DME)의 효과를 조사하였다. DME는 PMA와 Calcium ionophore 병행처리(PMACI)에 의해 유도되는 β-hexosaminidase 분비와 TNF-α, IL-4, HDC 발현을 현저히 억제하였다. 또한 PMACI에 의해 유도되는 NF-κB, AP-1 활성과 p38 kinase, extracellular signal-regulated kinase 1/2 (ERK1/2)과 c-Jun N-terminal kinase (JNK)의 인산화가 DME 전처리에 의해 저해되었다. 이러한 결과들은DME가 비만세포 탈과립을 억제하고, MAPKs/NF-κB/AP-1 신호전달 경로를 통해 TNF-α, IL-4, HDC 발현을 억제한다는 것을 시사한다. 본 연구결과들로 보아 DME는 과민반응과 염증성 질환을 치료하는 약물로 개발될 가능성을 가지는 것으로 사료된다.

• Journal of Ginseng Research
• /
• 제43권1호
• /
• pp.95-104
• /
• 2019

Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-${\alpha}$, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (${\Delta}{\Psi}m$) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor $(NF)-{\kappa}B$, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, $NF-{\kappa}B$ nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the $NF-{\kappa}B$, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.

• 한국자원식물학회지
• /
• 제35권5호
• /
• pp.565-573
• /
• 2022

치주조직에 존재하는 주요한 세포의 한 형태인 인체 치은섬유아세포는 다양한 구강유해세균으로부터 염증이 유발되어지며, 그중 대표적으로 치주염 원인균인 P. gingivalis의 내독소인 LPS-PG로부터 염증성 자극에 반응하여 다양한 염증매개 물질을 분비한다. 본 연구에서는 치주염을 일으키는 주요한 원인균 중 하나인 P. gingivalis로 부터 분리한 LPS-PG를 이용하여 인체 치은섬유아세포주인 HGF-1 세포에 염증을 유도한 후 LRE에 대한 항염증 및 항산화 효과를 분석하였다. 실험 결과, LRE는 LPS-PG 유도에 따라 iNOS에 의한 NO 생성과 COX-2에 의한 PGE₂와 같은 염증 매개 인자의 발현 및 생성 억제와 함께 염증성 싸이토카인(TNF-α, IL-1β및 IL-6)의 생성 또한 억제하였다. 신호전달계에서 염증성 전사인자의 발현 경로를 확인하기 위하여 TLR4/Myd88/NF-κB의 활성을 확인한 결과, LRE 처리에 따라 농도 의존적으로 억제되는 것을 확인하였다. 또한 산화 환원 효소로 항염증효과를 나타내는 것으로 알려진2상 효소 중 하나인 NQO-1과 이의 전사인자인 Nrf2를 분석 한 결과 LRE 처리에 의해 효소의 활성이 높아지는 것을 확인할 수 있었다. 결론적으로 LRE는 TLR4/Myd88/NF-κB 신호전달 경로를 억제하고 NQO1/Nrf2 활성을 유도함으로써 HGF-1 세포에서 LPS-PG에 의해 유도된 염증을 억제하는 것으로 사료되며, 향후 LRE는 식·의약품 소재 개발에서 치주질환 개선의 가능성이 있는 후보물질이 될 수 있을 것으로 사료된다.

• Natural Product Sciences
• /
• 제24권1호
• /
• pp.13-20
• /
• 2018

Estragole is a naturally occurring phenylpropanoid obtained from essential oils found in a broad diversity of plants. Although the phenylpropanoids show many biological activities, clear regulation of the inflammatory signaling pathways has not yet been determined. Here, we scrutinized the anti-inflammatory effect of estragole. The anti-inflammatory effect of estragole was determined through the inhibitory mechanisms of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), nuclear factor kappa B ($NF-{\kappa}B$), and mitogen-activated protein kinases (MAPK) pathways and the activation of nuclear factor erythroid 2-related factor 2 (Nrf-2)/heme oxygenase (HO)-1 pathways in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Estragole significantly inhibited NO production, iNOS and COX-2 expression as well as LPS-induced $NF-{\kappa}B$ and MAPK activation. Furthermore, estragole suppressed LPS-induced intracellular ROS production but up-regulated the stress response gene HO-1 via the activation of transcription factor Nrf-2. These findings demonstrate that estragole inhibits the LPS-induced expression of inflammatory mediators via the down-regulation of iNOS, COX-2, $NF-{\kappa}B$, and MAPK pathways, as well as the up-regulation of the Nrf-2/HO-1 pathway, indicating that this phenylpropanoid has potential therapeutic and preventive applications in various inflammatory diseases.