• Title/Summary/Keyword: Release effect

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Involvement of Intracellular Ca2+-and PI3K-Dependent ERK Activation in TCDD-Induced Inhibition of Cell Proliferation in SK-N-SH Human Neuronal Cells

  • Yang, Seun-Ah;Lee, Yong-Soo;Jin, Da-Qing;Jung, Jae-Wook;Park, Byung-Chul;Lee, Yoon-Seok;Paek, Seung-Hwan;Jeong, Tae-Cheon;Choi, Han-Gon;Yong, Chul-Soon;Yoo, Bong-Kyu;Kim, Jung-Ae
    • Biomolecules & Therapeutics
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    • v.13 no.2
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    • pp.78-83
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    • 2005
  • 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) has previously shown to induce neurotoxicity through intracellular $Ca^{2+}$ increase in rat neurons. In this study we investigated the role and signaling pathway of intracellular $Ca^{2+}$ in TCDD-induced inhibition of neuronal cell proliferation in SK-N-SH human neuronal cells. We found that TCDD(10nM) rapidly increased the level of intracellular $Ca^{2+}$, which was completely blocked by the extracellular $Ca^{2+}$ chelation with EGTA (1 mM) or by pretreatment of the cells with the non-selective cation channel blocker. flufenamic acid (200 ${\mu}M$). However, pretreatment of the cells with dantrolene (25 ${\mu}M$) and TMB-8(10 ${\mu}M$), intracellular $Ca^{2+}$-release blockers, or a voltage-sensitive $Ca^{2+}$ channel blocker, varapamil (100 ${\mu}M$), failed to block the TCDD-induced $Ca^{2+}$ increase in the cells. In addition, TCDD induced a rapid and transient activation of phatidvlinositol 3-kinase (PI3K) and extracellular signal-regulated kinase 1/2(ERK1/2), which was ingnificantly blocked by the pretreatment with BAPTA, an intracellular $Ca^{2+}$ chelator, and LY294002, a PI3K inhibitor. Furthermore, inhibitors of PI3K, ERK, or an intracellular $Ca^{2+}$ chelator further potentiated the anti-proliferative effect of TCDD in the cells. Collectively, the results suggest that intracellular $Ca^{2+}$ and PI3K-dependent activation of ERK 1/2 may be involved in the TCDD-induced inhibition of cell proliferation in SK-N-SH human neuronal cells.

A Study on Antitumor Effect and Mechanism of Cortex ulmi pumilae Water Extract on HepG2 Hepatoma cell (유근피(楡根皮) 추출액(抽出液)이 HeoG2 간암세포(肝癌細胞)에 미치는 항암효과(抗癌效果) 및 기전(機轉)에 대(對)한 연구(硏究))

  • Choi, Su-Deock;Park, Young-Kweon;Kim, Gang-San;Kang, Byung-Ki;Han, Sang-Il
    • The Journal of Internal Korean Medicine
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    • v.21 no.2
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    • pp.259-266
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    • 2000
  • Objectives : The effects of aqueous extracts of Cortex ulmi pumilae (a traditional medicine for cancer treatment in oriental medicine) on the induction of apoptotic cell death were investigated in human liver origm hepatoma cell lines, HepG2. Methods : The death of HepG2 cells was markedly induced by the addition of extracts of Cortex ulmi pumilae in a dose-dependent manner. The apoptotic characteristic ladder pattern of DNA strand break was not observed in cell death of HepG2. In addition, it was not shown nucleus chromatin condensation and fragmentation under hoechst staining. However, by the using annexin V staining assay, externalizations of phosphatidylserine in HepG2 cell which were treated with Cortex ulmi pumilae extracts were detected in the early time (at 9 hr after extract treatment). Furthermore, LDH release was not detected in this early stage. Therefore, Cortex ulmi pumilae extracts-induced cell death of HepG2 cells is mediated by apoptotic death signal processes. Result : The activity of caspase 3-like proteases remained in a basal level in HepG2 cells which treated with the extract of Cordyceps sinensis. However, it was markedly increased in HepG2 cells which treated with two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K) which were differently extracted (respectively, 2.3 and 3.3 fold). On a while, the phosphotransferase activities of JNK1 was markedly induced in HepG2 cells which were treated with two extracts of Cortex ulmi pumilae. On the contrary, the activation of transcriptional activator, activating protein1(AP-1) and NF-kB were severely decreased by these two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K). In addition, antioxidants (GSH and NAC) and intracellular $Ca2^+$ level regulator (Bapta/AM and Thapsigargin) did not affect Cortex ulmi pumilae extracts-induced apoptotic death of HepG2 cells. Conclusions : In conclusion, our results suggest that two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K) induces the apoptotic death of human liver origin hepatoma HepG2 cells via activation of caspase 3-like proteases as well as JNK1, and inhibition of transcriptional activators, AP-1 and $NK-{\kappa}B$.

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Effects of Jagamcho-tang on the C6 Glial Cell Injured by LPS Combined PMA (자감초탕(炙甘草湯)이 LPS와 PMA에 의해 손상된 C6 glial 세포에 미치는 영향)

  • Cho, Nam-Su;Rhyu, Jun-Ki;Lee, In;Shin, Sun-Ho;Moon, Byung-Soon;Na, Young-Hoon
    • The Journal of Internal Korean Medicine
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    • v.21 no.3
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    • pp.467-475
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    • 2000
  • The water extracts of Jagamcho-tang has been used for treatment of arrhythmia and palpitation in oriental traditional medicine. Brain is provided with blood flow by heart. Jagamcho-tang has been studied on ischemia and infarction in heart. However, little is known about the mechanism by which the water extracts of Jagamcho-tang rescues brain cells from ischemic damages. To elucidate the protective mechanism on ischemic induced cytotoxicity, the effects of Jagamcho-tang on ischemia induced cytotoxicity and generation of nitric oxide(NO) are investigated in C6 glioma cells. Jagamcho-tang induce NO in a dose dependent manner up to 2.5mg/ml in C6 glioma cells. The pretreatment of Jagamcho-tang protect sodium nitroprusside(SNP) (2mM) induced cytotoxicity. This effect of Jagamcho-tang is mimicked by treatment by pretreatment of SNP($100{\mu}M$), an exogenous NO donor. NG-monomethyl-L-arginine($N^{G}MMA$), a specific inhibitor of nitric oxide synthase (NOS), significantly blocks the protective effects of Jagamcho-tang on cell toxicity by ischemia. In addition, lipopolysaccharide(LPS) and phorhol 12 myristate 13-acetate(PMA) treatment for 72h in C6 glial cells markedly induce NO, but treatment of the cells with the water extracts of Jagamcho-tang decrease nitrite formation in a dose dependent manner. In addition, LPS and PMA treatment for 72h induce severe cell death and LDH release into medium in C6 glial cells. However treatment of the cells with the water extracts of Jagamcho-tang dose not induce significant changes compare to control cells. Furthermore, the protective effects of the water extracts of Jagamcho-tang is mimicked by treatment of $N^{G}MMA$. Taken together, I suggest that the protective effects of the water extracts of Jagamcho-tang against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

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Effects of the Ethyl Acetate Soluble Fractions of Sophorae Radix In Langendorff Hearts (고삼 Ethyl Acetate 소분획이 적출 심장에 미치는 영향)

  • Kwon Kang Beom;Park Gwan Ha;Kim Woo Kyung;Kim Eun Kyung;Kim Goo Hwan;Ko Kwang Hak;Choi Yeon Seong;Zhang Geun Gook;Rho Seong Il;Han Dong Won;Cha Suk;Park Dae Young;Ryu Do Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.5
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    • pp.1309-1316
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    • 2004
  • We previously reported that the ethtyl acetate(EA) soluble fraction of Sophorae Radix(SR) water extract had the preventive effects against cardiovascular anaphylaxis elicited in experimental animals. In this study, we tested the anti-anaphylatic effects of the nine kinds of EA soluble subfractions in animal models such as Langendorff heart and anesthetized rats. These results were obtained as followed ; Among nine kinds of SR EA soluble subfractions, N10-16-2 and N10-16-9 fractions have an effects improving cardiovascular anaphylaxis in guinea pig Langendorff hearts. In passively anesthetized rats, N10-16-2 and N1 0-16-9 fractions of SR EA soluble subfractions have an effects improving cardiovascular anaphylaxis. N10-16-2 and N1 0-16-9 fractions of SR EA soluble subfractions inhibited the decrease of histamine release induced by compound 48180 and A-23187 in rat peritoneal mast cells. These results suggest that N10-16-2 and N10-16-9 fractions of SR EA soluble subfractions involve anti-anaphylactic molecules in cardiovascular system.

Gene Expression Profile of Rat Hypothalamus Treated with Electroacupuncture at ST36 Acupoint (족삼리 전침자극에 의한 흰쥐 hypothalamus의 유전자 발현 profile 분석)

  • Rho Sam Woong;Lee Gi Seog;Choi Gi Soon;Na Young In;Hong Moo Chang;Shin Min Kyu;Min Byung il;Bae Hyun Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.4
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    • pp.1041-1054
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    • 2004
  • Electroacupuncture (EA) has been reported to increase pain threshold, and to enhance the NK cell activity by up-regulation of IFN-γ and endogenous β-endolphin. For the purpose of understanding the molecular mechanism of EA stimulation, we analyzed the gene expression profile of rat hypothalamus, treated on Zusanli (ST36) with EA, in comparison with control group by oligonucleotide chip microarray (Affymetrix GeneChip Rat Neurobiology U34 Array) and real-time RT-PCR. Sprague-Dawley (S-D) male rats were stimulated at the Zusanli (ST36) acupoint in restriction holder. Simultaneously the control group was given only holder stress without EA stimulation. In order to prove the appropriateness of EA treatment, we measured spleen NK cell activity with standard 51Cr release assay. NK cell activity of EA group was significantly increased comparing to control group. The microarray and PCR results show that EA treatment up-regulates expression of genes associated with 1) nerve growth such as NGF induced factor A and VGF, 2) signal transduction such as 5HT3 receptor subunit, AMPA receptor binding protein and Na-dependent neurotransmitter transporter, and 3) anti-oxidation such as superoxide dismutase and glutathione S-transferase. In addition, the activity of the anti-oxidative enzyme, SOD of hypothalamus, liver and RBC was enhanced compared to that of control. The list of differentially expressed genes may implicate further insight on the mechanism of acupuncture effects.

Antagonic Effects of Dexamethasone on FK506-induced Antitumor Effects in Hep3B Cells (간암세포주(Hep3B cell)에서 FK506의 항암효과에 대한 dexamethasone의 길항효과)

  • Park, Hye-Min;Lee, Sei-Jin;Kim, Sun-Young;Go, Hyeon-Kyu;Jeon, Seol-Hee;Kim, Shang-Jin;Kang, Hyung-Sub;Kim, Jin-Shang
    • Journal of Veterinary Clinics
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    • v.28 no.6
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    • pp.549-554
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    • 2011
  • FK506 is a widespread immunosuppressive drug after liver transplantion in patients with advanced-stage hepatocellular carcinoma. Dexamethasone is frequently used as co-treatment in cytotoxic cancer therapy, e.g. to prevent nausea, to protect normal tissue or for other reasons. Our aim was to investigate antitumor effects of FK506 in Hep3B cells, one of differentiated human hepatocellular carcinoma cell lines and inhibitory effects of dexamethsone on FK506- induced antitumor effects. Cell injury was evaluated by biochemical assays as cell viability, lactate dehydrogenase (LDH) and reactive oxygen species (ROS) in Hep3B cells. Intracellular calcium concentration ([$Ca^{2+}$]i) and the level of activation of the c-Jun-N-terminal kinase (JNK) and the Bax protein in cultured Hep3B cells was measured. Exposure of 0.1 ${\mu}M$ FK506 to Hep3B cells led to cell death accompanied by a decrease in cell viability and an increase in LDH, ROS and [$Ca^{2+}$]i. FK506 induced an increase in activity of Bax and JNK protein but inhibited the activity of Bcl-2 protein. Treatment of dexamethsone, per se, had no effects on cell viability, LDH and ROS. However, co-treatment of FK506 and dexamethasone diminished the FK506-induced LDH release, ROS generation and JNK activation. These results demonstrate that FK506 has antitumor effect in Hep3B cells but the combination of FK506 and dexamethasone antagonizes the FK506-induced antitumor effects.

Anti-Inflammatory Effect of Licochalcone E, a Constituent of Licorice, on Lipopolysaccharide-Induced Inflammatory Responses in Murine Macrophages (Licochalcone E의 항염증 효과와 그 기전에 대한 연구)

  • Park, Geun-Mook;Jun, Jong-Gab;Kim, Jin-Kyung
    • Journal of Life Science
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    • v.21 no.5
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    • pp.656-663
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    • 2011
  • Licochalcone, a major phenolic constituent of the licorice species Glycyrrhiza inflata, a constituent of licorice, exhibits various biological properties, including chemopreventive-, antibacterial-, and anti-spasmodic activities. Recently, Licochalcone E (LicE) was isolated from the roots of Glycyrrhiza inflate, however its biological functions have not been fully examined. In the present study, we investigated the ability of LicE to regulate inflammation reactions in macrophages. Our in vitro experiments using murine macrophages, RAW264.7 cells, showed that LicE suppressed not only nitric oxide (NO) and prostaglandin $E_2$ generation, but also the expression of inducible NO synthase and cyclooxygenase-2 induced by lipopolysaccharide (LPS). Similarly, LicE inhibited the release of proinflammatory cytokines induced by LPS in RAW264.7 cells, including tumor necrosis factor-${\alpha}$ and interleukin-6. The underlying mechanism of LicE on anti-inflammatory action correlated with down-regulation of the nuclear factor-${\kappa}$B. Our data collectively indicate that LicE inhibited the production of several inflammatory mediators and might be used in the treatment of various inflammatory diseases.

Anti-Inflammatory Effect of Ligularia fischeri, Solidago virga-aurea and Aruncus dioicus Complex Extracts in Raw 264.7 Cells (곰취(Ligularia fischeri), 미역취(Solidago virga-aurea), 삼나물(Aruncus dioicus) 복합 추출물의 항염증 효과)

  • Kim, Dong-Hee;An, Bong-Jeun;Kim, Se-Gie;Park, Tae-Soon;Park, Gun-Hye;Son, Jun-Ho
    • Journal of Life Science
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    • v.21 no.5
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    • pp.678-683
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    • 2011
  • The objective of this study was to evaluate the skin inflammation effects of three herb mixture extracts, Ligularia fischeri, Solidago virga-aurea and Aruncus dioicus, which are from Ullung island in Korea. Regulatory mechanisms of cytokines and nitric oxide (NO) are involved in the immunological activity of Raw 264.7 cells. Tested cells were pretreated with 70% acetone extracts of Ligularia fischeri, Solidago virga-aurea and Aruncus dioicus (LSA-A) and further cultured for an appropriated time after lipopolyssacharide (LPS) addition. During the entire experimental period, 1, 10, and 100 ${\mu}g/ml$ of LSA-A had no cytotoxicity. In these concentrations, LSA-A inhibited the production of NO and prostaglandin $E_2$ ($PGE_2$), tumor necorsis factor-a (TNF-a), interleukin-1${\beta}$ (IL-1${\beta}$), interleukin-6 (IL-6) expression of inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2). LSA-A showed a 60% $PGE_2$ inhibition rate at 100 ${\mu}g/ml$. iNOS and COX-2 inhibition activities were 54%, and 65% at 100 ${\mu}g/ml$, respectively. In addition, LSA-A extract reduced the release of inflammatory cytokines including TNF-a, IL-1${\beta}$ and IL-6. These results suggest that LSA-A may have significant effects on inflammatory factors, and may be a potential anti-inflammatory therapeutic agent.

Differential Mechanisms of Vascular Relaxation between Alcohol Steamed Rhei Tangutici Radix et Rhizoma and Rhei Tangutici Radix et Rhizoma (당고특대황(唐古特大黃)의 주증(酒蒸) 여부가 혈관이완 기전에 미치는 영향)

  • Yang, Jae-Kyung;Shin, Heung-Mook
    • The Korea Journal of Herbology
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    • v.25 no.4
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    • pp.17-21
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    • 2010
  • Objectives : The aim of this study was to evaluate the differential mechnism of vasodilation of alcohol steamed Rhei Tangutici Radix et Rhizoma. (ART) and Rhei Tangutici Radix et Rhizoma. (RT) in rat thoracic aorta. Methods : Rat aortic ring preparations were mounted in organ baths with oxygenated (95% $O_2$-5% $CO_2$) Krebs-Ringer bicarbonate solutions at $37{\pm}0.5^{\circ}C$ and subjected to contractions or relaxations. Results : ART exerted vasorelaxation on phenylephrine(PE)-induced contraction in a dose dependent manner. Vasorelaxation effects of ART and RT were endothelium-independent. In the $Ca^{2+}$-free high KCl (60 mM) baths, the contraction of aortic rings induced by accumulative addition of $Ca^{2+}$ (0.3-10.0 mM) was significantly reduced by pre-treatment with both ART and RT for 10 min. The magnitude of vasodilatation was biggerin ART. Moreover, verapamil ($0.001{\mu}M$) and diltiazem ($10{\mu}M$), voltage operative $Ca^{2+}$channel blockers, attenuated the relaxation effect of ART but not that of RT. In the absence of extracellular $Ca^{2+}$, pre-incubation of the aortic rings with RT ($1.0mg/m{\ell}$) significantly reduced the contraction caused by PE but not that of ART. $K^+$ channel inhibitors such as glibenclamide (Gli, $10^{-5}M$), tetraethylammonium (TEA, 1 mM) and 4-aminopyridine (4-AP, 0.2 mM) significantly reduced the ART's vasorelaxation efficacy, but not that of RT. However, the relaxation effects of ART and RT were not inhibited by pre-treatment with indomethacin ($10^{-5}M$), and atropine ($10^{-6}M$). Conclusions : These results suggest that the endothelium-independent relaxation is due to inhibition of $Ca^{2+}$ influx via the suppression of $Ca^{2+}$ release from intracelluar store in RT but via both voltage operative $Ca^{2+}$channel blockage and $K^+$ channel activation in ART.

Smoking Rate and Its Related Factors in Collegians after Their Admission to the College (대학진학 이후 흡연율과 관련요인)

  • Seo, Dong-Bae;Kam, Sin;Han, Chang-Hyun;Park, Ki-Soo
    • Korean Journal of Health Education and Promotion
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    • v.25 no.3
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    • pp.111-124
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    • 2008
  • Objectives: The purpose of this study was to suggest effective methods for not only preventing college students from being exposed to smoking but also helping them stop smoking, by examining and analysing a variety of factors related to their smoking behavior. Methods: To accomplish the purpose, this study was carried out using 1,553 valid questionnaires selected from 1,584 questionnaires completed and returned by 1,800 randomly chosen students of 2 colleges and 3 universities in Gyeongsangbuk-do Province and Daegu City during the period of April 3 through April 21, 2006. Results: It was turned out that while the total smoking rate of whole students was 52.4% in male students and 9.1% in female students, the smoking rate after their admission to the college was 27.1% in males and 1.5% in females. It was also shown that both the perceived susceptibility and barrier factors of Health Belief Model were statistically significant, and that the perceived seriousness factors were entirely significant in all other variables except the body seriousness. The perceived benefit factors were significant in only the variable that there would not be any improvement in academic performance even after stopping smoking. A relation between smoking and stop smoking program or smoking prevention program showed that the non-smoking rate was significantly high among the college students who participated in such programs while in middle school. When variables having a significant effect on smoking students after their admission were analysed, it was shown that the smoking rate was higher among males than females students, and that the more the number of smoking friends is and the more the number of students thinking that stop smoking would make it difficult to release stress and make friends is, the higher the smoking rate is among students. It is required, therefore, to encourage students to continuously participate in more smoking prevention programs from middle school, and to put an emphasis on a variety of smoking-related illnesses and advantages from non-smoking. Conclusions: Since the current smoking rate among college students is relatively high but most of the smoking students surveyed are ready to actually try to stop smoking, it will be possible to significantly reduce the smoking rate among college students if proper methods are suggested to eliminate barrier factors they face while participating in the stop smoking programs.