• Title/Summary/Keyword: triggered release

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Anti-inflammatory Potential of Artemisia capillaris and Its Constituents in LPS-induced RAW264.7 Cells

  • Abdul, Qudeer Ahmed;Seong, Su Hui;Ahn, Bo Ra;Islam, Md Nurul;Jung, Hyun Ah;Choi, Jae Sue
    • Natural Product Sciences
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    • v.24 no.3
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    • pp.171-180
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    • 2018
  • Artemisia capillaris has been widely used as an alternative therapy for treating obesity and atopic dermatitis. It has been used as a hepatoprotactant. It is also used for ameliorating inflammatory reactions. Although there are several investigations on other Artemisia species, there is no systematic study describing the role of A. capillaris MeOH extract, its solvent soluble fractions, or derived anti-inflammatory principal components in regulating inflammatory conditions. Therefore, the objective of this study was to elucidate anti-inflammatory mechanisms of A. capillaris. Results revealed that MeOH extract of A. capillaris could decrease LPS-stimulated NO secretion. Of tested fractions, $CH_2Cl_2$, EtOAc, and n-BuOH strongly inhibited NO release from RAW264.7 cells. Bioactive mediators derived from $CH_2Cl_2$ and n-BuOH fractions elicited potent anti-inflammatory actions and strikingly abrogated LPS-triggered NO accumulation in RAW264.7 cells. Of particular interest, capillin and isoscopoletin possessed the most potent NO suppressive effects. Western blot analysis validated the molecular mechanism of NO inhibition and showed that capillin and isoscopoletin significantly down-regulated iNOS and COX-2 protein expression. Taken together, our results provide the first evidence that MeOH extract, $CH_2Cl_2$, EtOAc, and n-BuOH fractions from A. capillaris and its derived lead candidates can potently suppress inflammatory responses in macrophages by hampering NO release and down-regulating iNOS and COX-2 signaling.

Effects of Cheonggisan and Gagamcheonggisan on the anti-allegic and immune responses in mice (청기산(淸肌散)과 가미청기산(加味淸肌散)이 마우스의 항(抗)알레르기 및 면역반응(免疫反應)에 미치는 영향(影響))

  • Park Eun-Jeong;Kim Yang-Gwi
    • The Journal of Pediatrics of Korean Medicine
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    • v.12 no.1
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    • pp.183-210
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    • 1998
  • Cheonggisan(CGS) is well known for its effect on such allergic disease as urticaria and atopic dermatitis. Gagamcheonggisan(GCGS) was formulated by subtracting several herbs from CGS and adding several herbs to CGS. Even though it is being used frequently in the clinicai medicine for the treatment of above hypersensitivity diseases, basic study to make sure the mechanism of its action is rare. In this study the author tried to know the effect of CGS and GCGS on the vascular permeability, contact dermatitis, granular secretion from mast cells and function of macrophages. The results obtained in this study are as follows : 1. Administration of CGS and GCGS decreased the vascular permeability induced by serotonin and histamine. The decrease by serotonin is more typical and dose-dependent. 2. Administration of CGS and GCGS inhibited foot-pad and ear swelling responses induced by sheep red blood cells and picryl chloride respectively, the inhibition of foot-pad swelling responses is bigger than that of ear swelling responses and both of them are not dependent on the dose3. Treatment of peritoneal mast cells with CGS and GCGS water extract decreased the histamine release triggered by compound 48/80 in a dose dependent fashion 4. Administration of CGS and GCGS increased the phagocvtic activity of peritoneal macrophages and treatment of peritoneal macrophages with CGS activated phagocytic function in a dose dependent fashion. 5. Administration of CGS and GCGS enhanced such reactive oxygen intermediates(ROIs) as superoxide and hydrogen peroxide production from peritoneal macrophages. 6. Treatment of CGS and GCGS activated peritoneal macrophages for the production of ROIs. The above results show that CGS and GCGS decreased the hypersensitivity reactions by inhibiting non-specific inflammatory mediator release and vascular permeability without affecting general immune responsiveness.

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Intracellular Messenger Role of Cyclic Nucleotides in Exocrine Secretion of Guinea Pig Pancreas (취외분비에 미치는 cyclic nucleotides의 역할)

  • Lee, H.W.;Kim, W.J.;Hong, S.S.
    • The Korean Journal of Pharmacology
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    • v.13 no.2
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    • pp.41-48
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    • 1977
  • In 1968, Case et al. first studied the importance of cyclic AMP as an intermediate in the action of secretin and cholecystokinin-pancreozymin and they suggested that the action of secretin, not that of cholecystokinin-pancreozymin, may be mediated through cyclic AMP. Recently Albano et al. reported that in the exocrine pancreas each of the two major physiological functions is modulated a specific cyclic nucleotide, enzyme secretion by cyclic GMP, and fluid and ionic secretion by cyclic AMP. But in pancreas still conflicting results have been reported on the role of cyclic nucleotides in enzyme and electrolyte secretion. In these study, the role of cyclic nucleotides in the exocrine pancreatic secretion was examined. The results are as follows. 1) Very strong stimulation on amylase release from guinea pig pancreatic slice was produced by 1 unit of cholecystokinin-pancreozymin but as compared to that of cholecystokinin-pancreozymin very weak response was observed by 1 unit of secretion or $1\;{\mu}g$ of VIP. 2) Both cholecystokinin-pancreozymin and acetylcholine produced a rapid and marked rise in cyclic GMP as well as cyclic AMP in isolated pancreatic tissue. However, both secretin and VIP failed to alter significantly the basal level of cyclic GMP in pancreatic fragments. 3) Atropine inhibited acetylcholine mediated amylase release, but did not affect the cholecystokinin-pancreozymin response. Furthermore, atropine pretreatment produced a marked inhibitory effect on the increase of tissue cyclic nucleotides induced by cholecystokinin-pancreozymin and acetylcholine. In summary, these results suggest that whereas the pancreatic secretion produced by secretin and VIP is modulated by the formation of cyclic AMP, the pancreatic enzyme secretion in response to cholecystokinin-pancreozymin and acetylcholine is triggered by both cyclic AMP and cyclic GMP.

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Properties of Spontaneous Activity in Gastric Smooth Muscle

  • Suzuki, H.;Yamamoto, Y.;Hirst, G.D.S.
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.2
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    • pp.119-125
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    • 1999
  • Mammalian gastric smooth muscles generate spontaneous rhythmic contractions which are associated with slow oscillatory potentials (slow waves) and spike potentials. Spike potentials are blocked by organic $Ca^{2+}-antagonists,$ indicating that these result from the activation of L-type $Ca^{2+}-channel.$ However, the cellular mechanisms underlying the generation of slow wave remain unclear. Slow waves are insensitive to $Ca^{2+}-antagonists$ but are blocked by metabolic inhibitors or low temperature. Recently it has been suggested that Interstitial Cells of Cajal (ICC) serve as pacemaker cells and a slow wave reflects the coordinated behavior of both ICC and smooth muscle cells. Small segments of circular smooth muscle isolated from antrum of the guinea-pig stomach generated two types of electrical events; irregular small amplitude (1 to 7 mV) of transient depolarization and larger amplitude (20 to 30 mV) of slow depolarization (regenerative potential). Transient depolarization occurred irregularly and membrane depolarization increased their frequency. Regenerative potentials were generated rhythmically and appeared to result from summed transient depolarizations. Spike potentials, sensitive to nifedipine, were generated on the peaks of regenerative potentials. Depolarization of the membrane evoked regenerative potentials with long latencies (1 to 2 s). These potentials had long partial refractory periods (15 to 20 s). They were inhibited by low concentrations of caffeine, perhaps reflecting either depletion of $Ca^{2+}$ from SR or inhibition of InsP3 receptors, by buffering $Ca^{2+}$ to low levels with BAPTA or by depleting $Ca^{2+}$ from SR with CPA. They persisted in the presence of $Ca^{2+}-sensitive$ $Cl^--channel$ blockers, niflumic acid and DIDS or $Co^{2+},$ a non selective $Ca^{2+}-channel$ blocker. These results suggest that spontaneous activity of gastric smooth muscle results from $Ca^{2+}$ release from SR, followed by activation of $Ca^{2+}-dependent$ ion channels other than $Cl^-$ channels, with the release of $Ca^{2+}$ from SR being triggered by membrane depolarization.

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Relationship of the Signal Transduction-mediated Proteins and Enzymes to Contractility and Plasticity in Skeletal Muscles (골격근의 수축과 가소성에 대한 신호전달-매개 단백질 및 관련 효소의 상관성)

  • Kim, Jung-Hwan
    • The Journal of Korean Physical Therapy
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    • v.19 no.4
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    • pp.1-14
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    • 2007
  • Background: It is generally accepted that skeletal muscle contraction is triggered by nerve impulse and intracellular $Ca^{2+}\;([Ca^{2+}]_i)$ released from intracellular $Ca^{2+}$ stores such as sarcoplasmic reticulum (SR). Specifically, this process, called excitation-contraction (E-C) coupling, takes place at intracellular junctions between the plasma membrane, the transverse (T) tubule L-type $Ca^{2+}$ channel (dihydropyridine-sensitive L-rype $Ca^{2+}$ channel, DHPR, also called tetrads), and the SR $Ca^{2+}$ release channel (ryanodine-sensitive $Ca^{2+}$ release channel, RyR, also called feet) of internal $Ca^{2+}$ stores in skeletal muscle cells. Furthermore, it has been reported that the $Ca^{2+-}$ dependent and -independent contraction determine the expression of skeletal muscle genes, thus providing a mechanism for tightly coupling the extent of muscle contraction to regulation of muscle plasticity-related excitation-transcription (E-T) coupling. Purpose: Expression and activity of plasticity-associated enzymes in gastrocnemius muscle strips have not been well studied, however. Methods: Therefore, in this study the expression and phosphorylation of E-C and E-T coupling-related mediators such as protein kinases, ROS(reactive oxygen species)- and apoptosis-related substances, and others in gastrocnemius muscles from rats was examined. Results: I found that expression and activity of MAPKs (mitogen-activated protein kinases, ERK1/2, p38MAPK, and SAPK/JNK), apoptotic proteins (cleaved caspase-3, cytochrome c, Ref-1, Bad), small GTP-binding proteins (RhoA and Cdc42), actin-binding protein (cofilin), PKC (protein kinase C) and $Ca^{2+}$ channel (transient receptor potential channel 6, TRPC6) was observed in rat gastrocnemius muscle strips. Conclusion: These results suggest that MAPKs, ROS- and apoptosis-related enzymes, cytoskeleton-regulated proteins, and $Ca^{2+}$ channel may in part functionally import in E-C and E-T coupling from rat skeletal muscles.

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Invisible Signals from the Underground: Bacterial Volatiles Elicit Plant Growth Promotion and Induce Systemic Resistance

  • Ryu, Choong-Min;Farag, Mohammed A.;Pare, Paul. W.;Kloepper, Joseph W.
    • The Plant Pathology Journal
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    • v.21 no.1
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    • pp.7-12
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    • 2005
  • Plant growth-promoting rhizobacteria (PGPR) are a wide range of root-colonizing bacteria with the capacity to enhance plant growth and control plant pathogens. Here we review recent progress that indicate some PGPR strains release a blend of volatile organic compounds (VOCs) that promote growth in Arabidopsis seedlings and induce resistance against Erwinia carotovora subsp. carotovora. In particular, the volatile components 2,3-butanediol and acetoin released exclusively from the PGPR strains triggered the greatest level of growth promotion and induced systemic resistance. Pharmacological applications of 2,3-butanediol promoted the plant growth and induced resistance, while bacterial mutants blocked in 2,3-butanediol and acetoin synthesis was devoid of growth-promotion and induced resistance capacities. The results suggested that the bacterial VOCs play a critical role in the plant growth promotion and induced resistance by PGPR. Using transgenic and mutant lines of Arabidopsis, we provide evidences that the signal pathway activated by volatiles from one PGPR strain is dependent on cyto-kinin activation for growth promotion and dependent on an ethylene-signaling pathway for induced pathogen resistance. This discovery provides new insight into the role of bacterial VOCs as initiators of both plant growth promotion and defense responses in plants.

Modulation of Subcellular Ca2+ Signal by Fluid Pressure in Rat Atrial Myocytes

  • Woo Sun-Hee;Morad Martin
    • Biomolecules & Therapeutics
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    • v.14 no.1
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    • pp.19-24
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    • 2006
  • Atrial chambers serve as mechanosensory systems during the haemodynamic or mechanical disturbances, which initiates arrhythmia. Atrial myocytes, lacking t-tubules, have two functionally separate sarcoplasmic reticulums (SRs): those at the periphery close to the surface membrane, and those at the cell interior (center) not associated with the membrane. To explore possible role of fluid pressure (FP) in the regulation of atrial local $Ca^{2+}$ signaling we investigated the effect of FP on subcellular $Ca^{2+}$ signals in isolated rat atrial myocytes using confocal microscopy. FP was applied to whole area of single myocyte with pressurized automatic micro-jet (200-400 $mmH_2O$) positioned close to the cell. Application of FP enhanced spontaneous occurrences of peripheral and central $Ca^{2+}$ sparks with larger effects on the peripheral release sites. Unitary properties of single sparks were not altered by FP. Exposure to higher FP often triggered longitudinal $Ca^{2+}$ wave. These results suggest that fluid pressure may directly alter excitability of atrial myocytes by activating $Ca^{2+}$-dependent ionic conductance in the peripheral membrane and by enhancing spontaneous activation of central myofilaments.

Fisetin Suppresses Macrophage-Mediated Inflammatory Responses by Blockade of Src and Syk

  • Kim, Jun Ho;Kim, Mi-Yeon;Kim, Jong-Hoon;Cho, Jae Youl
    • Biomolecules & Therapeutics
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    • v.23 no.5
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    • pp.414-420
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    • 2015
  • Flavonoids, such as fisetin (3,7,3',4'-tetrahydroxyflavone), are plant secondary metabolites. It has been reported that fisetin is able to perform numerous pharmacological roles including anti-inflammatory, anti-microbial, and anti-cancer activities; however, the exact anti-inflammatory mechanism of fisetin is not understood. In this study, the pharmacological action modes of fisetin in lipopolysaccharide (LPS)-stimulated macrophage-like cells were elucidated by using immunoblotting analysis, kinase assays, and an overexpression strategy. Fisetin diminished the release of nitric oxide (NO) and reduced the mRNA levels of inducible NO synthase (iNOS), tumor necrosis factor (TNF)-${\alpha}$, and cyclooxygenase (COX)-2 in LPS-stimulated RAW264.7 cells without displaying cytotoxicity. This compound also blocked the nuclear translocation of p65/nuclear factor (NF)-${\kappa}B$. In agreement, the upstream phosphorylation events for NF-${\kappa}B$ activation, composed of Src, Syk, and I${\kappa}B{\alpha}$, were also reduced by fisetin. The phospho-Src level, triggered by overexpression of wild-type Src, was also inhibited by fisetin. Therefore, these results strongly suggest that fisetin can be considered a bioactive immunomodulatory compound with anti-inflammatory properties through suppression of Src and Syk activities.

HSV-1 ICP27 induces apoptosis by promoting Bax translocation to mitochondria through interacting with 14-3-3θ

  • Kim, Ji Ae;Kim, Jin Chul;Min, Jung Sun;Kang, Inho;Oh, Jeongho;Ahn, Jeong Keun
    • BMB Reports
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    • v.50 no.5
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    • pp.257-262
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    • 2017
  • The subcellular localization of Bax plays a crucial role during apoptosis. In response to apoptotic stimuli, Bax translocates from the cytoplasm to the mitochondria, where it promotes the release of cytochrome c to the cytoplasm. In cells infected with HSV-1, apoptosis is triggered or blocked by diverse mechanisms. In this study, we demonstrate how HSV-1 ICP27 induces apoptosis and modulates mitochondrial membrane potential in HEK 293T cells. We found that ICP27 interacts with $14-3-3{\theta}$ which sequesters Bax to the cytoplasm. In addition, ICP27 promotes the translocation of Bax to the mitochondria by inhibiting the interaction between $14-3-3{\theta}$ and Bax. Our findings may provide a novel apoptotic regulatory pathway induced by ICP27 during HSV-1 infection.

Dual Functional Gd(III)-DOTA Liposomes for Cancer Therapy and Diagnosis as a Theragnostic Carrier

  • Han, Hee Dong;Jung, Suk Hyun;Seong, Hasoo;Cho, Sun Hang;Shin, Byung Cheol
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.154-158
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    • 2013
  • Development of dual functional liposome has been studied for cancer theragnostics. Therefore, we focused on ultrasound-sensitive liposomes with doxorubicin (DOX) and gadolinium (Gd) as a theragnostic carrier having a potential for cancer therapy and diagnosis. In this study, Gd(III)-DOTA-modified sonosensitive liposomes (GL) was developed using chemically synthesized Gd(III)-DOTA-DPPE lipid. Sonosensitivity of GL to 1 MHz ultrasound induced 25% of DOX release. The relaxivities ($r_1$) of GL were $7.33-10.34\;mM^{-1}s^{-1}$, which was higher than that of MR-bester$^{(R)}$. Intracellular delivery of DOX from GL by ultrasound irradiation was evaluated according to ultrasound intensity, resulting in increase of uptake of DOX released from ultrasound-triggered GLs compared to GL3 or Doxil$^{(R)}$ without ultrasound. Taken together, this study shows that the paramagnetic and sonosensitive liposomes, GL, is a novel and highly effective delivery system for drug with the potential for broad applications in human disease.