• Title/Summary/Keyword: Dose-response

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Effect of Copper on the Regulation of Ferroportin-1 Gene Expression (구리가 Ferroportin-1 유전자 발현 조절에 미치는 영향)

  • Park, Bo-Yoen;Chung, Ja-Yong
    • Journal of Nutrition and Health
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    • v.42 no.5
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    • pp.434-441
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    • 2009
  • Ferroportin-1 (FPN) is a transporter protein that is known to mediate iron export from macrophages. The purpose of this study was to investigate the effect of copper on the regulation of FPN gene expression in J774 mouse macrophage cells. J774 cells were treated with various concentrations of $CuSO_4$ and RT-PCR analyses were performed to measure the steady-state levels of mRNAs for FPN and divalent metal transporter 1 (DMT1, an iron importer). Copper treatment significantly increased FPN mRNAs in a dose-dependent manner, but didn't change the levels of DMT1 mRNA. Experiments with transcriptional inhibitor actinomycin D (0.5 ${\mu}g$/mL) revealed that copper treatment did not affect the half-life of FPN mRNAs in J774 cells. On the other hand, results from luciferase reporter assays showed that copper directly stimulated the promoter activity of FPN. In summary, our data showed copper induced FPN mRNA of macrophages via a transcriptional rather than post-transcriptional mechanisms.

Effect of Ouabain on the Interaction of Mitochondria with Calcium (Mitochondria의 Calcium Uptake에 미치는 Ouabain의 영향)

  • Hong, Sa-Ack;Park, Chan-Woong;Kim, Myung-Suk;Chung, Myung-Hee
    • The Korean Journal of Pharmacology
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    • v.8 no.1
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    • pp.67-75
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    • 1972
  • Many studies on the mechanism of the inotropic action of cardiac glycosides have shown the possible intimate relationship between the mobilization of intracellular calcium and inotropic effect. Evidence obtained from recent studies suggests that cardiac glycosides may increase the intracellular $Ca^{++}$ concentration through the release of this ion from cellular or intracellular membrane. It seemed imperative to study the effect of ouabain on the interaction between mitochondria and $Ca^{++}$, because mitochondria are known to have a rather powerful $Ca^{++}$ pump mechanism which may have an important role on the regulation of intracellular $Ca^{++}$ concentration. The present investigations was made into the effect of ouabain on $Ca^{++}$ untake of mitochondria in the presence of ATP and its dependence on $K^+$ and $Na^+$ in the medium. The results are summarized as follows: 1. The rate of rise in the turbidity of superprecipitation was solely influenced by ionic strength of the medium, not by the species of ion, i.e. $Na^+$ or $K^+$. The higher ionic strength suppressed and the lower enhanced the rate of superprecipitation respectively. 2. No effect of ouabain was found on the rate of superprecipitation. 3. Mitochondria depressed the rate of superpretipitation, and the depressed rate of superprecipitation by mitochondria was reversed by ouabain, and the degree of this reversal was almost identical in $Na^+$ and $K^+$ medium. 4. $Ca^{++}$ uptake of mitochondria was inhibited by ouabain in the presence of ATP and the degree of inhibition showed the dose-response manner in terms of concentration of ouabain. 5. In the absence of ATP, mitochondria took or the $Ca^{++}$ in initial period but released it later. Such uptake and release of $Ca^{++}$ was not influenced by ouabain. 6. It is suggested that intracellular calcium mobilization by ouabain through the action upon the mitochondria was due to inhibition on ATP-dependent $Ca^{++}$ uptake by this agent, not to the action upon so called binding.

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Comparative studies of various transfection processes for the optimal luminescence signal analysis (최적의 luminescence 신호 분석을 위한 유전자 전달 방법의 비교연구)

  • Park, Seohyun;Lee, Sunghou
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.640-647
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    • 2016
  • By minimizing fluorescence interference phenomena, aequorin-based luminescence technology can provide a relatively sensitive detection platform with integration of $G{\alpha}16$ protein in order to track internal calcium mobilization by G protein-coupled receptors (GPCR). In this type of cell-based functional assay format, it is essential to optimize the transfection process of a receptor and $G{\alpha}16$ protein. For this study, corticotropin releasing factor receptor subtype 2(CRF2) was set as a model system to generate three stable cells with CRF2 and $G{\alpha}16$ in addition to transiently transfected cells under three different conditions. Agonist (sauvagine) and antagonist (K41498) responses in those cells were analyzed to develop the optimum transfection process. As a result, the effective signal ratio in the dose response experiments of sauvagine and K41498 were at least 10-fold higher (z'=0.77) in CRF2-$G{\alpha}16$ stable cells. For the transient transfection cells, stable expression of $G{\alpha}16$ prior to the CRF2 represented a two-fold higher signal (z'=0.84) than the other cases of transient transfection. In conclusion, for the utilization of transient transfection processes to develop a cell-based GPCR functional assay system, it is suggested to introduce various target receptors after stable expression of $G{\alpha}16$ protein.

Downward Decrease of Non-adrenergic Non-cholinergic Relaxation in the Rabbit Gastric Body (토끼 위체에서 비-아드레날린 비-콜린성 이완반응의 하행성 감소)

  • Hong, Eun-Ju;Choi, Ji-Eun;Park, Mi-Sun;Kim, Myung-Woo;Choi, Su-Kyung;Hong, Sung-Cheul
    • YAKHAK HOEJI
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    • v.41 no.3
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    • pp.389-398
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    • 1997
  • Non-adenergic non-cholinergic (NANC) innervation on the circular muscle of the rabbit gastric body was investigated by observing the magnitudy of relaxations induced by the elec trical field stimulation (EFS). Strips were cut from the greater curvature of the gastric body and stimulated with 5s trains of 0.5 ms pulses at 1-20 Hz, 40 V. The EFS induced transient frequency-dependent contractons, followed by a slowly recovering relaxation ewpecially at higher frequency of the EFS. In the presence of atropine and guanethidine, the contractions were virtually abolished, while the frequency-dependent relaxations by the EFS remained unaffected. The magnitude of relaxations progressively decreased as the location of the strips gets closer to the bottom of the gastric body. The relaxations were ablished by tetrodotoxin, indicating that their orgin is the NANC nerve stimulation. NG-nitro-L-arginine (L-NNA, 10-$100{\mu}M$), the inhibitor of nitric oxide (NO)-synthase, caused a concentration-dependent inhibition of the NANC relaxations. The inhibitory effects of L-NNA were not affected gy the location of the strips and were reversed by L-arginine, the precursor of NO-biosynthesis. Hemoglobin (20-$60{\mu}M$), a NO scavenger, inhibited the NANC relaxation s in a concentration-dependent manner. This inhibition was more prominent in the NANC relaxations observed in the lower portion of the gastric body and the relaxations induced ly lower frequencies of the EFS. Methyelne blue (10-$100{\mu}M$), an inhibitor of cytosolic guanylate cyclase, markedly inhibited the NANC relaxations, almost abolishing the response at a higher dose ($100{\mu}M$). These results suggest that NANX innervation of the rabbit gastric body progeressively decrease as he location of the strips gets closer to the bottom of the gastric body, and that the NANC relaxation is primarily mediated by NO-guanosine 3',5'-cyclic monophophate (cyclic GMP).

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Effects of Caffeic Acid Methyl Ester from Mentha arvensis Linne var. piperascens on Function of E6 Oncoprotein of HPV 16 (박하에서 분리한 Caffeic Acid Methyl Ester가 자궁경부암 바이러스 발암단백질 E6의 기능에 미치는 영향)

  • Baek, Tae-Woong;Lee , Kyung-Ae;Ahn , Min-Jung;Joo, Hae-Hyung;Oh , Hyun-Cheol;Ahn , Jong-Seok;Cho , Yong-Kweon;Myung , Pyung-Keun;Yoon, Do-Young
    • YAKHAK HOEJI
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    • v.48 no.6
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    • pp.328-334
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    • 2004
  • Cervical cancer is one of the leading causes of female death. Viral oncoproteins E6 and E7 are selectively retained and expressed in carcinoma cells infected with HPV (Human pa pilloma virus) type 16 and cooperated in immotalization and transformation of primary keratinocyte. E6 and E7 oncoproteins interfere the functions of tumor suppressor proteins p53 and retinoblasoma protein (pRb), respectively. Among a lots of natural products, Mentha arvensis Linne var.piperascens have inhibitory effects on bindings between E6 oncoprotein and tumor suppressor p53, E3 ubiqutin- protein ligase (E6AP). HPV oncoprotein inhibitors from Mentha piperita L. were isolated by solvent partition and column chromatography (Silica gel, RP-18) and inhibitory compounds were finally purified by HPLC using an ELISA screening system based on binding between E6 and E6AP. The aim of this study is to identify the structure of inhibitory compounds and to investigate whether these compounds have inhibitory effects on functions of E6 oncoprotein. We investigated whether caffeic acid methyl ester (CAM) extracted from Mentha piperita L. could inhibit the function of E6 oncoprotein. CAM inhibited the in vitro binding of E6 and E6AP which are essential for the binding and degradation of the tumor suppressor p53 and also inhibited the proliferation of human cervical cancer cell lines (SiHa and CaSKi) in a dose response manner. These results suggest that CAM inhibited the function of E6 oncoprotein, suggesting that it can be used as a potential drug for the treatment of cervical cancers infected with HPV.

Ginsenosides Inhibit N-, p-, arid Q-types but not L-type of $Ca^{2+}$ Channel in Bovine Chromaffin cells

  • Seok Chol;Jung, Se-Yeon;Kim, Hyun-Oh;Kim, Hack-Seang;Hyewhon Rhim;Kim, Seok-Chang;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.24 no.1
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    • pp.18-22
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    • 2000
  • In previous reports we have shown that ginsenosides inhibit high threshold voltage-dependent $Ca^{2+}$ channels in neuronal cells. However, these studies did not show whether ginsenosides-induced inhibition of $Ca^{2+}$ currents discriminates among the various $Ca^{2+}$ channel subtypes, although it is known that there are at least five different $Ca^{2+}$ channel subtypes in neuronal cells. In this study we investigated the effect of ginsenosides on high threshold voltage-dependent $Ca^{2+}$ channel subtypes using their selective $Ca^{2+}$ channel blockers nimodipine (L-type), $\omega$-conotoxin GVIA (N-type), or $\omega$-agatoxin IVA (P-type) in bovine chromaffin cells. We could observe that ginsenosides inhibited high threshold voltage-dependent $Ca^{2+}$ currents in a dose-dependent manner. The $IC_{50}$/ was about 120 $\mu$g/ml. Nimodipine had no effect on ginsenosides response. However, the effect of ginsenosides on $Ca^{2+}$ currents was reduced by $\omega$-conotoxin GVIA, $\omega$-agatoxin IVA, and mixture of nimodipine, $\omega$-contoxin GVIA, and $\omega$-agatoxin IVA. These data suggest that ginsenosides are negatively coupled to three types of calcium channels in bovine chromaffin cell, including an $\omega$-conotoxin GVIA-sensitive (N-type) channel, an $\omega$-agatoxin IVA-sensitive (P-type) channel and nimodipine/$\omega$-conotoxin GVIA/$\omega$-agatoxin IVA-resistant (presumptive Q-type) channel.Q-type) channel.

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Immunomodulatory Effects of Fructus and Semen from Rosa rugosa on Macrophages (해당화의 과육 및 종자추출물의 대식세포 면역조절작용)

  • Kang, Nam-Sung;Sohn, Eun-Hwa
    • Korean Journal of Plant Resources
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    • v.23 no.5
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    • pp.399-405
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    • 2010
  • Rosa rugosa has been used as a folk medicine with various pharmacological properties for a long time in Asia. Recently, it has been reported that the extract of fractions from different parts of Rosa rugosa have various pharmacological effects on diverse diseases including diabetes, inflammatory diseases and tumor. We investigated effects of fructus extracts of Rosa rugosa(RRF) and semen extracts of this herb(RRS) on macrophage to evaluate the possibilities as a biological response modifier. We showed increased effects on tumoricidal activity, phagocytic activity, TNF-$\alpha$ and NO production in RRF-treated groups without direct tumor cell cytotoxicity. RRS-treated groups increased direct tumor cell cytotoxicity at high dose without tumoricial activity except increasing of TNF-$\alpha$ release. These results provide further possibilities for the beneficial immunomodulating effects of RRF on immune system with relatively larger safety margin rather than RRS.

The Inhibitory Effects of $Chrthami$ Semen Oil Pharmacopuncture (CSOP) on Synovial Membranes in Type II Collagen-Induced Arthritis Mice (홍화자유약침이 CIA 모델 생쥐의 윤활관절막 손상 억제에 미치는 영향)

  • Back, Seong-Wook;Kim, Eun-Jung;Hwang, Ji-Hoo;Yoon, Jong-Hwa;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.29 no.1
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    • pp.115-125
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    • 2012
  • Objectives : The purpose of this study is to observe the inhibitory effects of $Chrthami$ semen oil pharmacopuncture(CSOP) on CIA (collagen-induced arthritis) mice. Materials and Methods : Two types of experiments were conducted: $in$ $vitro$ assay, inhibition of MIF mRNA and TNF-${\alpha}$ mRNA expressions in synovial membranes was observed, and $in$ $vivo$ assay, $1{\mu}{\ell}/kg$ CSOP was injected every day to the left $Weizhong$ ($BL_{40}$) from day 3 to 21 after induction of CIA, and changes in paw edema, apical surface morphology, neovascularization in synovial membranes, fibrosis, pro-inflammatory cytokines production, Th-1 differentiation, and anti-inflammatory effect were investigated. Results : 1. In synoviocytes of the CIA mice treated with CSOP, MIF mRNA and TNF-${\alpha}$ mRNA expressions were down-regulated in a dose-dependent manner. 2. Paw edema of the CIA mice treated with CSOP was diminished. 3. Tissue injury in the synovial membranes, capillary distribution and fibrosis were reduced in CSOP-treated mice. 4. MIF, TNF-${\alpha}$, IL-6, MMP-9 expressions were repressed in CSOP-treated mice during the experiment to observe the inhibitory effect on cytokines production in early stage RA. 5. IL-12 and CD28 were reduced in CSOP-treated mice during the observation of inhibitory effect on Th 1 differentiation. 6. PPAR-${\gamma}$ was increased during the experiment to observe the anti-inflammatory effect of CSOP. Conclusions : The results may suggest that administration treatment using $Chrthami$ semen oil pharmacopuncture decreases the inflammatory response on an Animal Model with CIA.

PLEIOTROPHIN EFFECTS ON BINDING AND SUBSEQUENT OSTEOGENESIS OF HUMAN MESENCHYMAL STEM CELLS (Pleiotrophin이 골수 줄기 세포의 부착 및 골형성에 미치는 효과에 대한 연구)

  • Yoon, Jung-Ho;Eune, Jung-Ju;Jang, Hyon-Seok;Rim, Jae-Suk;Lee, Eui-Seok;Kim, Dae-Sung;Kwon, Jong-Jin
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.28 no.2
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    • pp.111-117
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    • 2006
  • An area of current research is investigating the app1ication of human mesenchymal stem cells or hMSCs as a cell-based regenerative therapy. In order to achieve effective bone regeneration, appropriate matrices functioning as cell-carriers must be identified and optimized in terms of function, efficacy and biocompatibility. Two methods of approaching optimization of matrices are to facilitate adhesion of the donor hMSCs and furthermore to facilitate recruitment of host progenitor cells to osteoblastic differentiation. Pleiotrophin is an extracellular matrix protein that was first identified in developing rat brains and believed to be associated with developing neuronal pathways. A recent publication by Imai and colleagues demonstrated that transgenic mice with upregulated pleiotrophin expression developed a greater volume of cortical as well as cancellous bone. The proposed mechanism of action of pleiotrophin is demonstrated here. Through either environmental stresses and/or intracellular regulation, there is an increase in pleiotrophin production. The pleiotrophin is released extracellularly into areas requiring bone deposition. A receptor-mediated process recruits host osteoprogenitor cells into these areas. Therefore, the aim of our study was to investigate the osteoconductive properties of pleiotrophin. We wanted to determine if pleiotrophin coating facilitates cellular adhesion and furthermore if this has any effect on hMSCs derived bone formation in an animal model. The results showed a dose dependent response of cellular adhesion in fibronectin samples, and cellular adhesion was facilitated with increasing pleiotrophin concentrations. Histologic findings taken after 5 weeks implantation in SCID mouse showed no presence of bone formation with only a dense fibrous connective tissue. Possible explanations for the results of the osteogenesis assay include inappropriate cell loading.

Proliferative and Inhibitory Activity of Siberian ginseng (Eleutherococcus senticosus) Extract on Cancer Cell Lines; A-549, XWLC-05, HCT-116, CNE and Beas-2b

  • Cichello, Simon Angelo;Yao, Qian;Dowell, Ashley;Leury, Brian;He, Xiao-Qiong
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.11
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    • pp.4781-4786
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    • 2015
  • Siberian ginseng (Eleutherococcus senticosus) is used primarily as an adaptogen herb and also for its immune stimulant properties in Western herbal medicine. Another closely related species used in East Asian medicine systems i.e. Kampo, TCM (Manchuria, Korea, Japan and Ainu of Hokkaido) and also called Siberian ginseng (Acanthopanax senticosus) also displays immune-stimulant and anti-cancer properties. These may affect tumour growth and also provide an anti-fatigue effect for cancer patients, in particular for those suffering from lung cancer. There is some evidence that a carbohydrate in Siberian ginseng may possess not only immune stimulatory but also anti-tumour effects and also display other various anti-cancer properties. Our study aimed to determine the inhibitory and also proliferative effects of a methanol plant extract of Siberan ginseng (E. senticosus) on various cancer and normal cell lines including: A-549 (small cell lung cancer), XWLC-05 (Yunnan lung cancer cell line), CNE (human nasopharyngeal carcinoma cell line), HCT-116 (human colon cancer) and Beas-2b (human lung epithelial). These cell lines were treated with an extract from E. senticosus that was evaporated and reconstituted in DMSO. Treatment of A-549 (small cell lung cancer) cells with E. senticosus methanolic extract showed a concentration-dependent inhibitory trend from $12.5-50{\mu}g/mL$, and then a plateau, whereas at 12.5 and $25{\mu}g/mL$, there is a slight growth suppression in QBC-939 cells, but then a steady suppression from 50, 100 and $200{\mu}g/mL$. Further, in XWLC-05 (Yunnan lung cancer cell line), E. senticosus methanolic extract displayed an inhibitory effect which plateaued with increasing dosage. Next, in CNE (human nasopharyngeal carcinoma cell line) there was a dose dependent proliferative response, whereas in Beas-2 (human lung epithelial cell line), an inhibitory effect. Finally in colon cancer cell line (HCT-116) we observed an initially weak inhibitory effect and then plateau.