• Title/Summary/Keyword: respiratory inhibitor

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Reactive Oxygen Species Mediates Lysophosphatidic Acid-induced Migration of SKOV-3 Ovarian Cancer Cells (SKOV-3 난소암 세포주에서 lysophosphatidic acid 유도 세포의 이동에 있어 활성산소의 역할)

  • Kim, Eun Kyoung;Lee, Hye Sun;Ha, Hong Koo;Yun, Sung Ji;Ha, Jung Min;Kim, Young Whan;Jin, In Hye;Shin, Hwa Kyoung;Bae, Sun Sik
    • Journal of Life Science
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    • v.22 no.12
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    • pp.1621-1627
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    • 2012
  • Cell motility plays an essential role in many physiological responses, such as development, immune reaction, and angiogenesis. In the present study, we showed that lysophosphatidic acid (LPA) modulates cancer cell migration by regulation of generation of reactive oxygen species (ROS). Stimulation of SKOV-3 ovarian cancer cells with LPA strongly promoted migration. but this migration was completely blocked by pharmacological inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Inhibition of the ERK pathway had no effect on migration. Stimulation of SKOV-3 ovarian cancer cells with LPA significantly induced the generation of ROS in a time-dependent manner. LPA-induced generation of ROS was significantly blocked by pharmacological inhibition of PI3K or Akt, but inhibition of the ERK signaling pathway had little effect. LPA-induced generation of ROS was blocked by pretreatment of SKOV-3 ovarian cancer cells with an NADPH oxidase inhibitor, whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I had no effect. Scavenging of ROS by N-acetylcysteine completely blocked LPA-induced migration of SKOV-3 ovarian cancer cells. Inhibition of NADPH oxidase blocked LPA-induced migration whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I did not affect LPA-induced migration of SKOV-3 ovarian cancer cells. Given these results, we suggest that LPA induces ROS generation through the PI3K/Akt/NADPH oxidase signaling axis, thereby regulating cancer cell migration.

The Significance of Plasma Urokinase-type Plasminogen Activator and Type 1 Plasminogen Activator Inhibitor in Lung Cancer (폐암에서 혈장 Urokinase-Type Plasminogen Activator 및 Type 1 Plasminogen Activator Inhibitor의 의의)

  • Park, Kwang-Joo;Kim, Hyung-Jung;Ahn, Chul-Min;Lee, Doo-Yun;Chang, Joon;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.516-524
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    • 1997
  • Background : Cancer invasion and metastasis require the dissolution of the extracellular matrix in which several proteolytic enzymes are involved. One of these enzymes is the urokinase-type plasminogen activator(u-PA), and plasminogen activator inhibitors(PAI-1, PAI-2) also have a possible role in cancer invasion and metastasis by protection of cancer itself from proteolysis by u-PA. It has been reported that the levels of u-PA and plasminogen activator inhibitors in various cancer tissues are significantly higher than those in normal tissues and have significant correlations with tumor size and lymph node involvement. Here, we measured the concentration of plasma u-PA and PAI-1 antigens in the patients with lung cancer and compared the concentration of them with histologic types and staging parameters. Methods : We measured the concentration of plasma u-PA and PAI-1 antigens using commercial ELISA kit in 37 lung cancer patients, 21 benign lung disease patients and 24 age-matched healthy controls, and we compared the concentration of them with histologic types and staging parameters in lung cancer patients. Results : The concentration of u-PA was $1.0{\pm}0.3ng/mL$ in controls, $1.0{\pm}0.3ng/mL$ in benign lung disease patients and $0.9{\pm}0.3ng/mL$ in lung cancer patients. The concentration of PAI-1 was $14.2{\pm}6.7ng/mL$ in controls, $14.9{\pm}6.3ng/mL$ in benign lung disease patients, and $22.1{\pm}9.8ng/mL$ in lung cancer patients. The concentration of PAI-1 in lung cancer patients was higher than those of benign lung disease patients and controls. The concentration of u-PA was $0.7{\pm}0.4ng/mL$ in squamous cell carcinoma, $0.8{\pm}0.3ng/mL$ in adenocarcinoma, 0.9ng/mL in large cell carcinoma, and $1.1{\pm}0.7ng/mL$ in small cell carcinoma. The concentration of PAI-1 was $22.3{\pm}7.2ng/mL$ in squamous cell carcinoma, $22.6{\pm}9.9ng/mL$ in adenocarcinoma, 42 ng/mL in large cell carcinoma, and $16.0{\pm}14.2ng/mL$ in small cell carcinoma. The concentration of u-PA was 0.74ng/mL in stage I, $1.2{\pm}0.6ng/mL$ in stage II, $0.7{\pm}0.4ng/mL$ in stage IIIA, $0.7{\pm}0.4ng/mL$ in stage IIIB, and $0.7{\pm}0.3ng/mL$ in stage IV. The concentration of PAI-1 was 21.8ng/mL in stage I, $22.7{\pm}8.7ng/mL$ in stage II, $18.4{\pm}4.9ng/mL$ in stage IIIA, $25.3{\pm}9.0ng/mL$ in stage IIIB, and $21.5{\pm}10.8ng/mL$ in stage IV. When we divided T stage into T1-3 and T4, the concentration of u-PA was $0.8{\pm}0.4ng/mL$ in T1-3 and $0.7{\pm}0.4ng/mL$ in T4, and the concentration of PAI-1 was $17.9{\pm}5.6ng/mL$ in T1-3 and $26.1{\pm}9.1ng/mL$ in T4. The concentration of PAI-1 in T4 was significantly higher than that in T1-3. The concentration of u-PA was $0.8{\pm}0.4ng/mL$ in M0 and $0.7{\pm}0.3ng/mL$ in M1, and the concentration of PAI-1 was $23.6{\pm}8.3ng/mL$ in M0 and $21.5{\pm}10.8ng/mL$ in M1. Conclusions : The plasma levels of PAI-1 in lung cancer were higher than benign lung disease and controls, and the plasma levels of PAI-1 in T4 were significantly higher than T1-3. These findings suggest involvement of PAI-1 with local invasion of lung cancer, but it should be confirmed by the data on comparison with pathological staging and tissue level in lung cancer.

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The Role of NF-${\kappa}B$ in the TNF-$\alpha$-induced Apoptosis of Lung Cancer Cell Line (폐암세포주의 TNF-$\alpha$ 유발 apoptosis에서 NF-${\kappa}B$의 역할)

  • Kim, J.Y.;Lee, S.H.;HwangBo, B.;Lee, C.T.;Kim, O.H.;Han, S.K.;Shim, O.S.;Yoo, C.G.
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.2
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    • pp.166-179
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    • 2000
  • Background: The main reason for the failure of anti-cancer chemotherapy is the build up of resistance by cancer cells to apoptosis. The activation of NF-${\kappa}B$ in many cancer cell lines is reported to be underlying mechanism behind the build up of resistance of cancer cells to apoptosis. However, this relationship varied depending on the cells used in the experiments. In this study, the role of NF-${\kappa}B$ activation in the TNF-$\alpha$-induced apoptosis in lung cancer cell line was evaluated. Methods: NCI-H157 cells were used in all experiments. Cells were exposed to a high dose of TNF-$\alpha$(20 ng/ml) for 24 or 48 hours with or without blocking NF-${\kappa}B$ activation. TNF-$\alpha$-induced activation of NF-${\kappa}B$ was inhibited either by overexpression of $I{\kappa}B{\alpha}$-super repressor($I{\kappa}B{\alpha}$-SR) or by pre-treatment with proteasome inhibitor. Cell viability and apoptosis were evaluated with MTT assay and Western blot analysis for PARP fragment, respectively. Results: Cell viability of NCI-H157 cells was not affected by TNF-$\alpha$ treatment alone; however, combined treatment with TNF-$\alpha$ and cycloheximide reduced cell viability significantly, indicating that resistance to TNF-$\alpha$ is mediated by the new proteins synthesized after TNF-$\alpha$ stimulation. To evaluate the role of NF-${\kappa}B$ in the transcription of anti-apoptotic proteins. delete NF-${\kappa}B$ activation was inhibited before TNF-$\alpha$ stimulation. as described above. $AD5I{\kappa}B{\alpha}$-SR-transduction inhibited TNF-$\alpha$-induced nuclear translocation of p65. TNF-$\alpha$-induced cell death and apoptosis increased after inhibition of TNF-$\alpha$-induced activation of NF-${\kappa}$ by methods. Conclusion: These results suggest that TNF-$\alpha$-induced activation of NF-${\kappa}B$ may be closely related to the acquisition of the resistance to TNF-$\alpha$-induced apoptosis in lung cancer cells. Therefore. blocking of NF-${\kappa}B$ pathway can be a useful therapeutic modality in the treatment of lung cancer.

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Physio-chemical studies on the seed browning in mature green peppers stored at low-temperature (Part 1) -Changes in between-step metabolites and substrates in the seed-browning effect- (녹숙(綠熟)고추의 저온저장(低溫貯藏)에 따른 종자갈변(種子褐變)에 관(關)한 생리화학적연구(生理化學的硏究) -제 1 보(第 1 報) 종자갈변(種子褐變)에 관계(關係)되는 기질(基質)과 중간대사성분(中間代謝成分)의 변화(變化)-)

  • Lee, Sung-Woo
    • Korean Journal of Food Science and Technology
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    • v.3 no.1
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    • pp.29-36
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    • 1971
  • When a low-temperature treatment was given to a small sweet pepper variety Zairaisisi, the seed browning effect appeared soon. This change attracted the studies to determine and discuss the browning metabolites, polyphenolic compounds, and changes in their between-step components. (1) Chlorogenic acids were found as a polyphenolic compound in seed, whereas no flavanol-type polyphenol was observed. (2) There was sharp increase in total polyphenol content and chlorogenic acid with a low-temperature treatment. The contents of these substrates dropped below that of room-temperature treatment after the browning effect took place. (3) A marked increase in between-step metabolites phenylalanine, tyrosine, shikimic acid contents, and thus assumed activated shikimate pathway in this process. (4) It was suggested by determining the effect of specific metabolic inhibition and respiratory inhibitor administrations on enzymes that active biosynthesis of polyphenolic compounds takes place in shikimate pathway with combination of phosphoenolpyruvate and erythrose-4-phosphate connected to TCA cycle jaming after an active EMP pathway was gone through with sugars in pepper seeds at a low-temperature. (5) It was also suggested from the observation of increased K ion flow-out in pepper seeds with a low-temperature treatment that there is an abnormality in the plasma membrance.

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Primary Dilated Cardiomyopathy in a Miniature Pinscher Dog (미니어쳐 핀셔견에서 발생한 확장성 심근질환)

  • Kim, Jung-Hyun;Park, Chul;Ko, Ki-Jin;Kang, Byeong-Teck;Jung, Dong-In;Kim, Ju-Won;Kim, Ha-Jung;Lim, Chae-Young;Lee, So-Young;Cho, Sue-Kyung;Park, Hee-Myung
    • Journal of Veterinary Clinics
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    • v.23 no.3
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    • pp.349-354
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    • 2006
  • A 9-month-old, female Miniature Pinscher(MP) dog weighing 1.97kg was presented because of periodic syncopal episode for 5 months. This case was diagnosed as primary dilated cardiomyopathy based on respiratory distress history, weak femoral pulse, generalized cardiomegaly, pulmonary edema, marked dilation of left atrium(LA) and left ventricle(LV), decreased wall thickness of LV and interventricular septum(IVS), increased EPSS in echocardiography, and young age of onset in the absence of other cardiovascular disorders. The patient was stabilized by application of diuretics(Furosemide, 2 mg/kg, SC, q 1 hr) and venodilator(Nitroglycerine patch, 0.5 mg/kg, q 12 hrs). Clinical signs were improved with medical management of positive inotropic vasodilator(Pimobendan, 0.2 mg/kg, PO, q 12 hrs) and angiotensin-converting enzyme(ACE) inhibitor(benazepril, 0.5 mg/kg, PO, q 12 hrs), potassium gluconate gel(2 mEq/dog, PO, q 12 hrs) and, L-carnitine(50 mg/kg, PO, q 12 hrs). The dog still maintains stable clinical status 10 months after the first visit. We report the rare case of DCM in small breed dog, which corresponds to the diagnosis and treatment of typical DCM in large breed dog.

Endotoxin-induced Acute Lung Injury is Mediated by PAF Produced via Remodelling of Lyso PAF in the Lungs

  • Lee, Young-Man;Kim, Teo-An
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.219-226
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    • 2000
  • In order to elucidate the role of platelet activating factor (PAF) in the acute lung injury induced by endotoxin (ETX), activities of phospholipase A2, lyso PAF acetyltransferase and oxidative stress by neutrophilic respiratory burst were probed in the present study. To induce acute lung injury, $100\;{\mu}g$ of E.coli ETX (type 0127; B8) was instilled directly into the tracheae of Sprague-Dawley rats. Five hours after the ETX instillation, induction of acute lung injury was confirmed by lung leak index and protein contents in the bronchoalveolar lavage (BAL) fluid. At the same time, lung phospholipase A2 (PLA2) activity and expression of group I and II secretory type PLA2 were examined. In these acutely injured rats, ketotifen fumarate, known as lyso PAF acetyltransferase inhibitor and mepacrine were administered to examine the role of PAF in the pathogenesis of the acute lung injury. To know the effect of the ETX in the synthesis of the PAF in the lungs, lyso PAF acetyltransferase activity and PAF content in the lungs were measured after treatments of ETX, ketotifen fumarate and mepacrine. In addition, the role of neutrophils causing the oxidative stress after ETX was examined by measuring lung myeloperoxidase (MPO) and enumerating neutrophils in the BAL fluid. To confirm the oxidative stress in the lungs, pulmonary contents of malondialdehyde (MDA) were measured. After instillation of the ETX in the lungs, lung leak index increased dramatically (p<0.001), whereas mepacrine and ketotifen decreased the lung leak index significantly (p<0.001). Lung PLA2 activity also increased (p<0.001) after ETX treatment compared with control, which was reversed by mepacrine and ketotifen (p<0.001). In the examination of expression of group I and II secretory PLA2, mRNA synthesis of the group II PLA2 was enhanced by ETX treatment, whereas ketotifen and WEB 2086, the PAF receptor antagonist, decreased the expression. The activity of the lysoPAF acetyltransferase increased (p<0.001) after treatment of ETX, which implies the increased synthesis of PAF by the remodelling of lysoPAF in the lungs. Consequently, the contents of the PAF in the lungs were increased by ETX compared with control (p<0.001), while mepacrine (p<0.001) and ketotifen (p<0.01) decreased the synthesis of the PAF in the lungs of ETX treated rats. The infiltration of the neutrophils was confirmed by measuring and enumerating lung MPO and the neutrophils in the BAL fluid respectively. Compared with control, ETX increased lung MPO and number of neutrophils in BAL significantly (p<0.001) whereas mepacrine and ketotifen decrerased number of neutrophils (p<0.001) and MPO (p<0.05, p<0.001, respectively). The lung MDA contents were also increased (p<0.001) by ETX treatment, but treatment with mepacrine (p<0.001) and ketotifen (p<0.01) decreased the lung MDA contents. Collectively, we conclude that ETX increases PLA2 activity, and that the subsequently increased production of PAF was ensued by the remodelling of the lyso PAF resulting in tissue injury by means of oxidative stress in the lungs.

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The Effects of $Hwangryunhaedok$-$tang$ Pharmacopuncture by the Anti-inflammatory Action of Suppression of iNOS Production on Mice with Allergic Rhinitis (황련해독탕 약침액의 iNOS 생성 억제를 통한 항염증효과가 알레르기성 비염 유발 생쥐의 치료에 미치는 영향)

  • Cho, Jae-Yong;Kim, Yu-Jong;Kim, Eun-Jung;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.29 no.1
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    • pp.89-101
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    • 2012
  • Objectives : The purpose of this study was find out the therapeutic effects of its exclusive use on the rat with allergic rhinitis. Materials and Methods : Thirty Sprague-Dawley rats were divided into three group : normal group, control group and sample group. To induce the allergic rhinitis in control group and sample group, rats were sensitized intraperitoneally with 0.1% ovalumin solution 3 times at intervals of 1 week. Then intranasal sensitization was performed by diffusing 0.1% ovalumin solution 3 times at intervals of 2 days. After that time, rats in the sample group were administered by $Yonghyang$($LI_{20}$) subcutaneously to treat the inflammation. Results : 1. The anti-oxidant effects of $Hwangryunhaedok-tang$ extract was dose-dependantly increased. 2. The RAW 264.7 cells were treated with LPS for 1 hours prior to the addition of indicated concentrations ($0.4,-1.0mg/m{\ell}$) of HHT, and the cells were further incubated for 24 hours. The LPS-induced iNOS mRNA expression and NO production were dose-dependantly decreased in HHT treated RAW 264.7 cells. 3. The number of eosinophil in HP noticeably decreased than CON and this decrease had probability. The infiltration of eosinophil in HP noticeably decreased than CON. 4. The damaged mucosa as disruption of cilia in respiratory cell and vacant mucose secreting cell were increased CON, but HP same as normal configuration. Decrease of PAS positive cell were shown in CON, but goblet cell occupied with neutral mucous were shown in HP. Decrease of mucosal stress(HSP70). Decrease of perennial sign(PPAR-${\gamma}$). Decrease of icthing and sneezing intricate neurotransmitter-(substance P). 5. The anti-inflammation of HHT pharmacopuncture for AR caused mucosa comes to result as belows. Decrease of pre-inflammation cytokine(TNF-${\alpha}$). Decrease of transcription factor (NF-${\kappa}B$ p65). Decrease of transcription factor inhibitor(p-$I{\kappa}B$). Decrease of inflammation cytokine(iNOS). Conclusions : The results may suggest that administration treatment using $Hwangryunhaedok-tang$ pharmacopucnture decreases the inflammatory response on an animal model with allergic rhinitis.

MiR-144-3p and Its Target Gene β-Amyloid Precursor Protein Regulate 1-Methyl-4-Phenyl-1,2-3,6-Tetrahydropyridine-Induced Mitochondrial Dysfunction

  • Li, Kuo;Zhang, Junling;Ji, Chunxue;Wang, Lixuan
    • Molecules and Cells
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    • v.39 no.7
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    • pp.543-549
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    • 2016
  • MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neuro-degenerative diseases, Parkinson's disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, ${\beta}$-amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes involved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor ${\gamma}$ coactivator-$1{\alpha}$(PGC-$1{\alpha}$), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.

Antiviral Activity of Plant-derived Natural Products against Influenza Viruses (식물 유래 천연물의 인플루엔자에 대한 항바이러스 활성)

  • Kim, Seonjeong;Kim, Yewon;Kim, Ju Won;Hwang, Yu-bin;Kim, Seong Hyeon;Jang, Yo Han
    • Journal of Life Science
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    • v.32 no.5
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    • pp.375-390
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    • 2022
  • Influenza viruses are zoonotic respiratory pathogens, and influenza infections have caused a substantial burden on public health systems and the livestock industry. Although currently approved seasonal influenza vaccines have shown potent protection efficacy against antigenically well-matched strains, there are considerable unmet needs for the efficient control of viral infections. Enormous efforts have been made to develop broadly protective universal influenza vaccines to tackle the huge levels of genetic diversity and variability of influenza viruses. In addition, antiviral drugs have been considered important interventions for the treatment of viral infections. The viral neuraminidase inhibitor oseltamivir is the most widely used antiviral medication to treat influenza A and influenza B viruses. However, unsatisfactory clinical outcomes resulting from side effects and the emergence of resistant variants have led to greater attention being paid to plants as a natural resource for anti-influenza drugs. In particular, the recent COVID-19 pandemic has underpinned the need for safe and effective antiviral drugs with a broad spectrum of antiviral activity to prevent the rapid spread of viruses among humans. This review outlines the results of the antiviral activities of various natural products isolated from plants against influenza viruses. Special focus is paid to the virucidal effects and the immune-enhancing effects of antiviral natural products, since the products have broad applications as inactivating agents for the preparation of inactivated vaccines and vaccine adjuvants.

Epigallocatechin-3-gallate suppresses hemin-aggravated colon carcinogenesis through Nrf2-inhibited mitochondrial reactive oxygen species accumulation

  • Seok, Ju Hyung;Kim, Dae Hyun;Kim, Hye Jih;Jo, Hang Hyo;Kim, Eun Young;Jeong, Jae-Hwang;Park, Young Seok;Lee, Sang Hun;Kim, Dae Joong;Nam, Sang Yoon;Lee, Beom Jun;Lee, Hyun Jik
    • Journal of Veterinary Science
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    • v.23 no.5
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    • pp.74.1-74.16
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    • 2022
  • Background: Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood. Objectives: We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action. Methods: Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model. Results: In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model. Conclusions: We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.