• Biomolecules & Therapeutics
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• 제30권4호
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• pp.360-367
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• 2022

Tropomyosin receptor kinase A (TrkA) protein is a receptor tyrosine kinase encoded by the NTRK1 gene. TrkA signaling mediates the proliferation, differentiation, and survival of neurons and other cells following stimulation by its ligand, the nerve growth factor. Chromosomal rearrangements of the NTRK1 gene result in the generation of TrkA fusion protein, which is known to cause deregulation of TrkA signaling. Targeting TrkA activity represents a promising strategy for the treatment of cancers that harbor the TrkA fusion protein. In this study, we evaluated the TrkA-inhibitory activity of the benzoxazole compound KRC-108. KRC-108 inhibited TrkA activity in an in vitro kinase assay, and suppressed the growth of KM12C colon cancer cells harboring an NTRK1 gene fusion. KRC-108 treatment induced cell cycle arrest, apoptotic cell death, and autophagy. KRC-108 suppressed the phosphorylation of downstream signaling molecules of TrkA, including Akt, phospholipase Cγ, and ERK1/2. Furthermore, KRC-108 exhibited antitumor activity in vivo in a KM12C cell xenograft model. These results indicate that KRC-108 may be a promising therapeutic agent for Trk fusion-positive cancers.

• IMMUNE NETWORK
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• 제22권2호
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• pp.19.1-19.20
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• 2022

Coxsackievirus B3 (CVB3) infection causes acute pancreatitis and myocarditis. However, its pathophysiological mechanism is unclear. Here, we investigated how lipid metabolism is associated with exacerbation of CVB3 pathology using high-fat diet (HFD)-induced obese mice. Mice were intraperitoneally inoculated with 1×10⁶ pfu/mouse of CVB3 after being fed a control or HFD to induce obesity. Mice were treated with mitoquinone (MitoQ) to reduce the level of mitochondrial ROS (mtROS). In obese mice, lipotoxicity of white adipose tissue-induced inflammation caused increased replication of CVB3 and mortality. The coxsackievirus adenovirus receptor increased under obese conditions, facilitating CVB3 replication in vitro. However, lipid-treated cells with receptor-specific inhibitors did not reduce CVB3 replication. In addition, lipid treatment increased mitochondria-derived vesicle formation and the number of multivesicular bodies. Alternatively, we found that inhibition of lipid-induced mtROS decreased viral replication. Notably, HFD-fed mice were more susceptible to CVB3-induced mortality in association with increased levels of CVB3 replication in adipose tissue, which was ameliorated by administration of the mtROS inhibitor, MitoQ. These results suggest that mtROS inhibitors can be used as potential treatments for CVB3 infection.

• BMB Reports
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• 제48권1호
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• pp.13-18
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• 2015

Alzheimer's disease severely compromises cognitive function. One of the mechanisms to explain the pathology of Alzheimer's disease has been the hypotheses of amyloid-pore/channel formation by complex $A{\beta}$-aggregates. Clinical studies suggested the moderate alcohol consumption can reduces probability developing neurodegenerative pathologies. A recent report explored the ability of ethanol to disrupt the generation of complex $A{\beta}$ in vitro and reduce the toxicity in two cell lines. Molecular dynamics simulations were applied to understand how ethanol blocks the aggregation of amyloid. On the other hand, the in silico modeling showed ethanol effect over the dynamics assembling for complex $A{\beta}$-aggregates mediated by break the hydrosaline bridges between Asp 23 and Lys 28, was are key element for amyloid dimerization. The amyloid pore/ channel hypothesis has been explored only in neuronal models, however recently experiments suggested the frog oocytes such an excellent model to explore the mechanism of the amyloid pore/channel hypothesis. So, the used of frog oocytes to explored the mechanism of amyloid aggregates is new, mainly for amyloid/pore hypothesis. Therefore, this experimental model is a powerful tool to explore the mechanism implicates in the Alzheimer's disease pathology and also suggests a model to prevent the Alzheimer's disease pathology.

• 한국약용작물학회지
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• 제11권4호
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• pp.298-305
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• 2003

Polygalae Radix (PR) from Polygala tenuifolia. (Polygalaceae) is traditionally used in China and Korea, since this herb has a sedative, antiinflammatory, and antibacterial agent. To extend pharmacological actions of PR in the CNS on the basis of its CNS inhibitory effect, the present study examined whether PR has the neuroprotective action against kainic acid (KA) -induced cell death in primarily cultured rat cerebellar granule neurons. PR, over a concentration range of 0.05 to $5{\mu}g/ml$ inhibited KA $(500\;{\mu}M)$-induced neuronal cell death, which was measured by a trypan blue exclusion test and a 3-[4,5-dimethylthiazol-2-y1]-2,5-diphenyl-tetrazolium bromide (MTT) assay. PR $(0.5{\mu}g/ml)$ inhibited glutamate release into medium induced by KA $(500\;{\mu}M)$, which was measured by HPLC. Pretreatment of PR $(0.5{\mu}g/ml)$ inhibited KA $(500\;{\mu}M)$-induced elevation of cytosolic calcium concentration $([Ca^{2+}]_c)$ which was measured by a fluorescent dye, Fura 2-AM, and generation of reactive oxygen species (ROS). These results suggest that PR prevents KA-induced neuronal cell damage in vitro.

• 생약학회지
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• 제54권1호
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• pp.21-26
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• 2023

Cirsium japonicum var. maackii is a traditional Korean wild perennial herb used to treat blood circulation, high blood pressure, inflammation, diabetes, and kidney damage. However, it is not known whether C. japonicum var. maackii directly improves endothelial dysfunction. In this study, the effect of C. japonicum var. maackii (CJE) on tumor necrosis factor (TNF)-α-induced vascular inflammation was investigated in vitro using human umbilical vein endothelial cells (HUVEC). As a result, CJE inhibited the production of VCAM-1, ICAM-1 and ROS increased by TNF-α in HUVECs. In addition, treatment with CJE attenuated IκB phosphorylation and translocation of NF-κB to the nucleus. These results suggest that CJE can suppress TNFα-induced adhesion molecule expression by blocking NF-κB signaling and inhibiting ROS generation. The results of this study show that CJE has the potential to be used to treat and prevent inflammation associated with endothelial cell damage.

• Journal of Veterinary Science
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• 제24권5호
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• pp.72.1-72.16
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• 2023

Background: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on the surface of Streptococcus dysgalactiae, coded with gapC, is a glycolytic enzyme that was reported to be a moonlighting protein and virulence factor. Objective: This study assessed GAPDH as a potential immunization candidate protein to prevent streptococcus infections. Methods: Mice were vaccinated subcutaneously with recombinant GAPDH and challenged with S. dysgalactiae in vivo. They were then evaluated using histological methods. rGAPDH of mouse bone marrow-derived dendritic cells (BMDCs) was evaluated using immunoblotting, reverse transcription quantitative polymerase chain reaction, and enzyme-linked immunosorbent assay methods. Results: Vaccination with rGAPDH improved the survival rates and decreased the bacterial burdens in the mammary glands compared to the control group. The mechanism by which rGAPDH vaccination protects against S. dysgalactiae was investigated. In vitro experiments showed that rGAPDH boosted the generation of interleukin-10 and tumor necrosis factor-α. Treatment of BMDCs with TAK-242, a toll-like receptor 4 inhibitor, or C29, a toll-like receptor 2 inhibitor, reduced cytokines substantially, suggesting that rGAPDH may be a potential ligand for both TLR2 and TLR4. Subsequent investigations showed that rGAPDH may activate the phosphorylation of MAPKs and nuclear factor-κB. Conclusions: GAPDH is a promising immunization candidate protein for targeting virulence and enhancing immune-mediated protection. Further investigations are warranted to understand the mechanisms underlying the activation of BMDCs by rGAPDH in a TLR2- and TLR4-dependent manner and the regulation of inflammatory cytokines contributing to mastitis pathogenesis.

• 한국동물생명공학회지
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• 제38권4호
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• pp.199-208
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• 2023

Background: Canine induced pluripotent stem cells (iPSCs) are an attractive source for veterinary regenerative medicine, disease modeling, and drug development. Here we used vitamin C (Vc) to improve the reprogramming efficiency of canine iPSCs, and its functions in the reprogramming process were elucidated. Methods: Retroviral transduction of Oct4, Sox2, Klf4, c-Myc (OSKM), and GFP was employed to induce reprogramming in canine fetal fibroblasts. Following transduction, the culture medium was subsequently replaced with ESC medium containing Vc to determine the effect on reprogramming activity. Results: The number of AP-positive iPSC colonies dramatically increased in culture conditions supplemented with Vc. Vc enhanced the efficacy of retrovirus transduction, which appears to be correlated with enhanced cell proliferation capacity. To confirm the characteristics of the Vc-treated iPSCs, the cells were cultured to passage 5, and pluripotency markers including Oct4, Sox2, Nanog, and Tra-1-60 were observed by immunocytochemistry. The expression of endogenous pluripotent genes (Oct4, Nanog, Rex1, and telomerase) were also verified by PCR. The complete silencing of exogenously transduced human OSKM factors was observed exclusively in canine iPSCs treated with Vc. Canine iPSCs treated with Vc are capable of forming embryoid bodies in vitro and have spontaneously differentiated into three germ layers. Conclusions: Our findings emphasize a straightforward method for enhancing the efficiency of canine iPSC generation and provide insight into the Vc effect on the reprogramming process.

• 대한한방내과학회지
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• 제31권1호
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• pp.153-165
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• 2010

Objectives : The aims of this study were to investigate the cytoprotective, antioxidative and inflammation genes inhibitory effects of Patriniae Radix on the mouse LLC-$PK_1$ cells (renal epithelial cells). Methods : The cytoprotective effect of Patriniae Radix was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The antioxidative effect was measured in terms of generation amount of superoxide anion radical (${\cdot}{O_2}^-$) by 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), nitric oxide (NO) by 4,5-diaminofluorescein (DAF-2), peroxynitrite ($ONOO^-$) by dihyldrorhodamine 123 (DHR 123) and prostaglandin $E_2$ ($PGE_2$) by $PGE_2$ immunoassay on $H_2O_2$-treated LLC-$PK_1$ cells. For measuring of inflammation genes inhibitory effects, western blot was performed to detect IKK-$\alpha$, phospho-$I{\kappa}B-\alpha$, NF-${\kappa}B$ (p50, p65), COX-2, iNOS, IL-$1{\beta}$ and VCAM-1 protein level in cytosol fractions from LLC-$PK_1$ cells. Results : Patriniae Radix extract reduced the $H_2O_2$-induced cell death and inhibited the amount of $H_2O_2$-induced ${\cdot}{O_2}^-$, NO, $ONOO^-$, $PGE_2$ generation dose-dependently on the mouse LLC-$PK_1$ cells in vitro. Also Patriniae Radix extract inhibited the expression of IKK-$\alpha$, phospho-$I{\kappa}B-\alpha$, COX-2, iNOS, IL-$1\beta$ and VCAM-1 genes dose-dependently by means of decreasing activation of NF-${\kappa}B$. Conclusions : According to above results, it was identified that Patriniae Radix had the cytoprotective, antioxidative and inflammation genes inhibitory effects. So it was suggested that Patriniae Radix would be effective to the treatment for the inflammatory process and inflammation-related diseases.

• 대한본초학회지
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• 제25권4호
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• pp.103-112
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• 2010

Objective : The aim of this study was to determine whether methanol extract of Do-Ki-Tang (DKT) inhibit free radical generation and production of nitrite an index of NO, $PGE_2$, iNOS, COX-2 and pro-inflammatory cytokines such as TNF-${\alpha}$, IL-$1{\beta}$, IL-6 and MCP-1 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods : Cytotoxic activity of extract on RAW 264.7 cells was measured using 5-(3-caroboxymeth-oxyphenyl)-2H-tetra-zolium inner salt (MTS) assay. The expression level of inflammatory response-related proteins was confirmed by western blot. The production of proinflammatory cytokines was measured by ELISA. Results : Our results indicated that DKT scavenged DPPH radical and nitric oxide in vitro. Moreover, DKT significantly inhibited the LPS-induced NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of TNF-${\alpha}$, IL-$1{\beta}$, IL-6 and MCP-1 formation in macrophages. Furthermore, DKT treatment also blocked LPS-induced intracellular ROS production and the activation of NF-${\kappa}B$ and MAPKs. Conclusion : Our data suggest that the anti-inflammatory effect of DKT is mediated through down-modulation of pro-inflammatory mediators and cytokines by blocking the signaling pathways of NF-${\kappa}B$ and MAPKs. These inhibitory effects by DKT represent a potential therapeutic approach to the treatment of inflammatory diseases.

• 한국식품영양과학회지
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• 제30권1호
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• pp.133-137
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• 2001

21종 식용식물의 부위별 MeOH Ex. DPPH와 TBA법으로 항산화 효과를 조사한 결과 DPPH를 이용한 유리라디칼 소거 효과는 참취잎, 쑥갓잎 및 머위잎에서 특이적으로 높은 효과가 관찰되었으며 시료추출물의 buffer에 의해 유발된 과산화지질 억제효과는 참외껍질의 억제 효과 강도는 $IC_{50}$ 값이 $10\mu\textrm{g}/mL$로 매우 강하였다. $S_2O_z$로 유발시킨 지질과산화에 대한 억제효과는 0.25 mg 농도에서 L-ascorbic acid의 과산화 억제율과 비교하면 가지 잎, 머위 잎, 감자껍질의 항산화 억제 효과가 가장 높았으며 $FeSO_4$로 유발시킨 지질과산화에 대한 억제효과는 쑥갓잎의 $IC_{50}$가 0.08 mg/mL로 특이적으로 높았다.