• Experimental and Molecular Medicine
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• v.54
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• pp.788-800
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• 2022

Cell-to-cell propagation of α-synuclein is thought to be the underlying mechanism of Parkinson's disease progression. Recent evidence suggests that inflammation plays an important role in the propagation of protein aggregates. However, the mechanism by which inflammation regulates the propagation of aggregates remains unknown. Here, using in vitro cultures, we found that soluble factors secreted from activated microglia promote cell-to-cell propagation of α-synuclein and further showed that among these soluble factors, TNF-α had the most robust stimulatory activity. Treatment of neurons with TNF-α triggered cellular senescence, as shown by transcriptomic analyses demonstrating induction of senescence-associated genes and immunoanalysis of senescence phenotype marker proteins. Interestingly, secretion of α-synuclein was increased in senescent neurons, reflecting acquisition of a senescence-associated secretory phenotype (SASP). Using vacuolin-1, an inhibitor of lysosomal exocytosis, and RNAi against rab27a, we demonstrated that the SASP was mediated by lysosomal exocytosis. Correlative light and electron microscopy and immunoelectron microscopy confirmed that propagating α-synuclein aggregates were present in electron-dense lysosome-like compartments. TNF-α promoted the SASP through stimulation of lysosomal exocytosis, thereby increasing the secretion of α-synuclein. Collectively, these results suggest that TNF-α is the major inflammatory factor that drives cell-to-cell propagation of α-synuclein by promoting the SASP and subsequent secretion of α-synuclein.

• Journal of Life Science
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• v.30 no.1
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• pp.106-112
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• 2020

Aminoacyl tRNA synthetase complex interacting multifunctional protein 2 (AIMP2) is a scaffolding protein required for the assembly of multi-tRNA synthetase, and it can exert pro-apoptotic activity in response to DNA damage. In the presence of DNA damage, AIMP2 binds to mouse double minute 2 homolog (MDM2) to protect p53 from MDM2 attack. TGF-β signaling results in the nuclear translocation of AIMP2, whereby AIMP2 interacts with FUSE-binding protein, and, thus, suppresses c-myc. TNF receptor-associated factor 2 (TRAF2) is an important mediator between TNF-receptors 1 and 2 which are involved in the signaling of c-Jun N-terminal kinase (JNK), nuclear factor κB (NF-κB), and p38 mitogen-activated protein kinases (MAPKs). TRAF2 is required for the activations of JNK and NF-κB via TNF-α and the mediation of anti-apoptosis signaling. AIMP2 can also enhance pro-apoptosis in the TNF-α signaling. During this signaling, AIMP2 assists the association of E3 ubiquitin ligase, the cellular inhibitor of apoptosis protein 1 (c-IAP1) which is well known and responsible for the degradation of TRAF2. The formation of a complex among AIMP2, TRAF2, and c-IAP1 results in proteasome-mediated TRAF2 degradation. AIMP2 can induce apoptosis via downregulation of TRAF2 to interact directly in TNF-α signaling. This review provides new insight into the molecular mechanism responsible for AIMP2 and TRAF2 complex formation and treatments for TNFα-associated diseases.

• The Korea Journal of Herbology
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• v.31 no.4
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• pp.1-10
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• 2016

Objectives: In Korean medicine, Curculiginis Rhizoma was treated for arthritis in remedy. But efficacy of Curculiginis Rhizoma on collagen induced arthritis was not revealed.Methods: Anti inflammatory effect of Curculiginis Rhizoma was researched in vitro with RAW264.7 cell and cell toxicity, levels of proinflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-12) and PGE2 were analyzed by ELISA assay. Inflammatory protein were analyzed by western blotting assay (JNK, ERK, COX-2, TNF-α and IL-1β). In vivo, collagen induced arthritis mice model was used to evaluate anti-inflammation effect through arthritis index, immune cell number and cytokine levels (TNF-α, IL-6 and IL-1β) in serum.Results: ECR(Extract of Curculiginis Rhizoma) has not shown cell toxicity in 200 ㎍/㎖ on RAW264.7 cell. ECR suppressed releases of NO, TNF-α, IL-1β, IL-6, IL-12 and PGE2 on RAW264.7 cell treated with lipopolysacharide (1 ㎍/㎖). And ECR inhibited regulation of TNF-α, IL-1β and IL-6 mRNA, reduced protein release of JNK, ERK, iNOS, COX-2, IL-1β and TNF-α. AI of group treated with ECR 200 ㎎/㎏ and 100 ㎎/㎏ were significantly decreased compared to vihicle arthritis mice, the number of immune cell in foot joint was increased on control mice but those of group treated with ECR 200 ㎎/㎏ and 100 ㎎/㎏ were significantly reduced. This results correspond with contens of cytokines (TNF-α, IL-1β and IL-6) in serum.Conclusions: Curculiginis Rhizoma has anti-inflammation effect on RAW264.7 cell in vitro and collagen induced arthritis in vivo. So it is necessary to research more mechanism for cascade imfact.

• BMB Reports
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• v.49 no.1
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• pp.57-62
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• 2016

Up-regulation of adhesion molecules plays an important role in the infiltration of leukocytes into the skin during the development of various inflammatory skin diseases, such as atopic dermatitis. In this study, we investigated the modulatory effects of 2,3-dimethoxy-2′-hydroxychalcone (DMHC) on tumor necrosis factor (TNF)-α-induced intercellular adhesion molecule-1 (ICAM-1) expression and monocyte adhesiveness, as well as the molecular mechanisms underlying its action in the HaCaT human keratinocyte cell line. Pre-treating HaCaT cells with DMHC significantly suppressed TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness. DMHC inhibited TNF-α-induced activation of NF-ᴋB. In addition, DMHC induced HO-1 expression as well as NRF2 activation. Furthermore, HO-1 knockdown using siRNA reversed the inhibitory effect of DMHC on TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that DMHC may inhibit TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes by suppressing the signaling cascades leading to NF-ᴋB activation and inducing HO-1 expression in keratinocytes. [BMB Reports 2016; 49(1): 57-62]

• Journal of Life Science
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• v.33 no.11
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• pp.859-867
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• 2023

Lupeol is a type of pentacyclic triterpene that has been reported to have therapeutic effects for treating many diseases; however, its effect on insulin resistance is unclear clear. This study examined the inhibitory effect of lupeol on the serine phosphorylation of insulin receptor substrate-1 in insulin resistance-induced 3T3-L1 adipocytes. 3T3-L1 cells were cultured and treated with tumor necrosis factor-α (TNF-α) for 24 hours to induce insulin resistance. Cells treated with different concentrations of lupeol (15 μM or 30 μM) or 100 nM of rosiglitazone were incubated. Then, lysed cells underwent western blotting. Lupeol exhibited a positive effect on the negative regulator of insulin signaling and inflammation-activated protein kinase caused by TNF-α in adipocytes. Lupeol inhibited the activation of protein tyrosine phosphatase-1B (PTP-1B)-a negative regulator of insulin signaling-and c-Jun N-terminal kinase (JNK); it was also an inhibitor of nuclear factor kappa-B kinase (IKK) and inflammation-activated protein kinases. In addition, Lupeol downregulated serine phosphorylation and upregulated tyrosine phosphorylation in insulin receptor substrate-1. Then, the downregulated phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway was activated, the translocation of glucose transporter type 4 was stimulated to the cell membrane, and intracellular glucose uptake increased in the insulin resistance-induced 3T3-L1 adipocytes. Lupeol may improve TNF-α-induced insulin resistance by downregulating the serine phosphorylation of insulin receptor substrate 1 by inhibiting negative regulators of insulin signaling and inflammation-activated protein kinases in 3T3-L1 adipocytes.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.249-254
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• 2020

Neutrophil extracellular trap (NET) formation is an immune response for the invasion of microbes. The purpose of this study is to examine the effect of zinc on NET formation of porcine peripheral blood polymorphonuclear cells (PMNs). The NET formation of PMNs was measured by fluorescence microplate reader. The production of tumor necrosis factor (TNF)-α in the culture supernatants from zinc-treated peripheral blood mononuclear cells (PBMCs) was measured by enzyme-linked immunosorbent assay (ELISA). Zinc itself did not have no effect on NET formation. However, the NET formation of PMNs was increased by culture supernatants from PBMCs treated with zinc. Also, the NET formation of PMNs was increased by recombinant porcine (rp) TNF-α. The production of TNF-α in PBMCs culture supernatants was shown to increase upon zinc treatments. These NET formations of PMNs increased by either culture supernatant from PBMCs treated with zinc or rpTNF-α were inhibited by treatment of anti-rpTNF-α polyclonal antibody (pAb). These results suggested that zinc has an immunostimulating effect on the NET formation of PMNs, which is mediated by TNF-α released from zinc-treated PBMCs. Therefore, zinc may play an important role for NET formation in the defense of porcine inflammatory diseases.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.295-300
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• 2021

This study was conducted to investigate the effect of Celeriac Extract on the production of pro-inflammatory cytokines. Inflammation is caused by pro-inflammatory cytokines TNF-α, IL-6, IL-1β and mediators such as free radicals. We investigated the effect of Celeriac Extract (1ug/mL, 10ug/mL, 100ug/mL) on the production of proinflammatory cytokines such as TNF-α, IL-6, IL-1β and NO by lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. These results demonstrated that Celeriac Extract inhibited the production of TNF-α, IL-6 and NO, without cytotoxicity significantly. Therefore, these findings suggest that Celeriac Extract may attenuate inflammatory responses via inhibition of production of pro-inflammatory cytokines and NO.

• Journal of Industrial Convergence
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• v.21 no.8
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• pp.69-74
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• 2023

This paper was conducted to examine the effect of Brussels Sprouts Extract on the inhibition of pro-inflammatory cytokines. The inflammatory response is manifested by mediators such as reactive oxygen species and inflammatory cytokines such as TNF-α, IL-1β, and IL-8. Therefore, this paper examined the toxicity to cells using the MTS assay, stimulated RAW264.7 macrophages with lipopolysaccharide (LPS), and stimulated reactive oxygen species such as NO and TNF-α, IL-1β, and IL-8. Inhibition of inflammatory cytokines after treatment with 10 mg/mL, 100 mg/mL, and 1000 mg/mL of Brussels Sprouts Extract was investigated. As a result of the experiment, Brussels Sprouts Extract inhibited NO production, TNF-α and IL-8 in a concentration-dependent manner without cytotoxicity, and showed significant inhibition especially at a concentration of 1000 mg/mL. Brussels Sprouts Extract, which inhibits the production of inflammatory cytokines, suggests the possibility of reducing inflammatory response and controlling inflammation, and can be seen as providing potential as a health functional food or prevention and treatment of inflammation.

• Analytical Science and Technology
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• v.28 no.4
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• pp.260-269
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• 2015

The protective effects of extract powder of Angelica gigas on the degeneration of the articular cartilage in rats was investigated with monosodium iodoacetate (MIA)-induced osteoarthritis, The treatment of high concentration (50 μg/mL) of Angelica gigas effectively inhibited nitric oxide (NO) production induced by interleukin-1α (IL-1α) without any cytotoxicity. Specifically, mRNA and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were dose dependently reduced by extract powder of Angelica gigas. Importantly, mRNA expression in articular cartilage of inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were clearly reduced. The inflammatory cytokines in blood were also reduced as well. These results suggested that the protective effects on the degeneration of the articular cartilage was derived from the inhibitory effects of mRNA and protein expression of tested inflammatory cytokines which is linked to prevent the degradation of proteoglycan (PG), the main matrix content in articular cartilage. Meanwhile, the 2 hrs incubation of decursin, a major compound of extract powder in rat whole blood rapidely converted decursin into decursinol which shows string anti-inflammatory activity. The coverted decursinol was detected after 8 hrs in whole blood by LC-MS/MS. Conclusively, the inhibitory effects of inflammatory cytokines production in osteoarthritis may be derived from the production of decursinol, which performs against inflammatroy cytokines like TNF-α, IL-1β, and IL-6.

• The Journal of Korean Obstetrics and Gynecology
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• v.34 no.3
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• pp.15-28
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• 2021

Objectives: This study was designed to examine the anti-cancer activity by innate immunomodulating and anti-inflammatory effects of liriopis tuber water extract (LPE). Methods: Cell cytotoxicity was tested with 4T1 mouse mammary carcinoma cells, spleen cells, macrophage, and RAW264.7 cells. To investigate innate immunomodulating effects of LPE on macrophage, we measured tumor necrosis factor-alpha (TNF-α), interleukin-12 (IL-12), and interleukin-10 (IL-10). To investigate innate immunomodulating effects of LPE on RAW264.7 cell, we measured TNF-α, interleukin-6 (IL-6). In addition, TNF-α and nitric oxide (NO) induced by lipopolysaccharide (LPS) were measured after treating with LPE to observe innate immunomodulating effect of LPE on RAW264.7 cell. Also, mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB) were examined by western blot analysis. Results: In an in vitro cytotoxicity analysis, LPE affected tumor cell growth above specific concentration. As compared with the control group, the production of TNF-α, IL-12, and IL-10 were increased in macrophage. As compared with the control group, the production of TNF-α and IL-6 were increased in RAW 264.7 cell. The expression of TNF-α and NO induced by LPS after treating LPE was decreased. In addition, treatment of RAW 264.7 cell with LPE increased the phosphorylation levels of p-extracellular signal-regulated kinase (p-ERK), p-Jun N-terminal kinase (p-JNK), and p-p38. Conclusions: LPE might have impact on the anti-cancer effect by activation of innate immune system and inflammation control.