• Molecules and Cells
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• v.41 no.6
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• pp.545-552
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• 2018

Spleen tyrosine kinase (SYK) is a cytosolic non-receptor protein tyrosine kinase. Because SYK mediates key receptor signaling pathways involving the B cell receptor and Fc receptors, SYK is an attractive target for autoimmune disease and cancer treatments. To date, representative oral SYK inhibitors, including fostamatinib (R406 or R788), entospletinib (GS-9973), cerdulatinib (PRT062070), and TAK-659, have been assessed in clinical trials. Here, we report the crystal structures of SYK in complex with two newly developed inhibitors possessing 4-aminopyrido[4,3-D]pyrimidine moieties (SKI-G-618 and SKI-O-85). One SYK inhibitor (SKI-G-618) exhibited moderate inhibitory activity against SYK, whereas the other inhibitor (SKI-O-85) exhibited a low inhibitory profile against SYK. Binding mode analysis indicates that a highly potent SYK inhibitor might be developed by modifying and optimizing the functional groups that interact with Leu377, Gly378, and Val385 in the G-loop and the nearby region in SYK. In agreement with our structural analysis, one of our SYK inhibitor (SKI-G-618) shows strong inhibitory activities on the ${\beta}$-hexosaminidase release and phosphorylation of SYK/Vav in RBL-2H3 cells. Taken together, our findings have important implications for the design of high affinity SYK inhibitors.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1449-1459
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• 2009

Coptidis rhizoma (huanglian) is an herb that is widely used in traditional Chinese medicine that has recently been shown to possess anticancer activity. However, the molecular mechanism underlying the anticancer effects of this herb is poorly understood. In this study, we investigated the anticancer activity of a combination of CR extract and arsenic trioxide, as well as the apoptotic pathway associated with its mechanism of action in human lung cancer H157 cells. Combined treatment of H157 cells with CR extract and arsenic trioxide resulted in significant apoptotic death. In addition, combined treatment with CR extract and arsenic trioxide acted in concert to induce a loss of mitochondrial membrane potential (${\Delta}{\Psi}$), the release of cytochrome c from mitochondria, and an increase in the expression of pro-apoptotic p53 and Bax protein, which resulted in activation of caspases and apoptosis. CR extract combined with arsenic trioxide also increased the lipid peroxidation, mRNA expression of DR4 and DR5 and caspase-8 activity. These data indicate that combined treatment with CR extract and arsenic trioxide enhanced apoptotic cell death in H157 cells through diverse pathways, including mitochondrial dysfunction and death receptors, particularly DR4 and DR5. Thus, this treatment may be an effective from of chemotherapy.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1349-1357
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• 2009

This study was performed to investigate the effects of Shigyungbanha-tang(SGT) on the lipopolysaccharide(LPS) induced acute lung injury(ALI) in mice. 1 and 24 h before LPS intratracheal instillation, control group was taken distilled water orally. Treated groups was taken each concentrate SGT(2.5 g/kg, 6.7 g/kg) by orally as same times. Normal group was not instilled with LPS and was taken distilled water. 24 h after LPS intratracheal instillation, lung histology was performed in inflated-fixed lungs in 3 mice of each groups. The other mice of each groups, bronchoalveolar lavege fluids(BALF) was obtained to measure proinflammatory cytokines(TNF-$\alpha$, IL-$1{\beta}$, IL-6) and blood sample was obtained to measure white blood cell(WBC). In vitro, the effect of SGT($100\;ug/m{\ell}$, $500\;ug/m{\ell}$, $1000\;ug/m{\ell}$) on the release of RANTES, TARC induced by TNF-$\alpha$ and IL-4 in human alveolar epithelial cell(A549) was examined. Histopathologically, SGT prevented LPS-induced lung injury. SGT decreased protein, TNF-$\alpha$, IL-$1{\beta}$ and IL-6 according to concentrations. In vitro, $500\;ug/m{\ell}$, $1000\;ug/m{\ell}$ concentrate SGT suppressed the expression of RANTES and TARC on A549 cells. On the basis of these results, SGT had a markedly anti-inflammatory effect in a clinically relevant model of ALI. Nevertheless, further investigations are required to determine the potential clinical usefulness of SGT in the adjunctive therapy of ALI.

• The Korean Journal of Physiology
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• v.16 no.1
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• pp.57-61
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• 1982

This study was conducted to investigate the effect of ingestion of rice meal with red pepper(Capsicum annuum) as a seasoning upon the plasma gastrin concentration of normal human subjects in Korea. Thirteen normal human subjects including male and female(mean age: 21 years, range: $20{\sim}24\;years$) were studied. After an overnight(about 15 hrs) fast each subject ingested a test meal and a control meal on different days. The test meal consisted of 250 g toiled rice, 250 ml radish soup containing red pepper(dried powder, 3 g), 50 g vegetables and 200 ml barley tea, corresponding to 7.0 g protein, 9.0 g fat and 82 g carbohydrate and the control meal consisted of the same amount as the test meal except that the radish soup was supplied without red pepper. The venous blood samples were drawn before and after the ingestion of meals at the following times: -30, 0, 15, 30, 45, 60, 90, and 120 min for the measurement of plasma gastrin concentration by means of radioimmunoassay. 1) Plasma gastrin concentration in response to the ingestion of control meal without red pepper increased significantly compared with the concentration in fasting state. 2) The increase of plasma gastrin concentration after the ingestion of test meal(containing red pepper) was significantly higher than that after the control meal. It is inferred from the above mentioned results that the ingestion of red pepper as a seasoning has a stimulatory influence on gastrin release in normal human subjects.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.353-359
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• 1998

In gastrointestinal smooth muscle, muscarinic stimulation by carbachol (CCh) activates nonselective cation channel current ($I_{CCh}$) which is facilitated by intracellular [$Ca^{2+}$] increase. Caffeine is widely used in experiments to mobilize $Ca^{2+}$ from intracellular stores. This study shows a strong inhibitory effect of caffeine on $I_{CCh}$ in guinea-pig gastric myocyte. In this study, the underlying mechanism of the inhibitory effect of caffeine was investigated. $I_{CCh}$ was completely suppressed by the addition of caffeine (10 mM) to the superfusing solution. Inhibition of $I_{CCh}$ by caffeine was not related to the intracellular cAMP accumulation which was expected from the phosphodiesterase-inhibiting effect of caffeine. The blockade of $InsP_3-induced$ $Ca^{2+}$ release by heparin had no significant effects on the activation of $I_{CCh}$. When the same cationic current had been induced by intracellular dialysis of $GTP[{\gamma}S]$ in order to bypass the muscarinic receptor, the inhibitory effect of caffeine was significantly attenuated. The results of this study indicate that both intracellular signalling pathways for $I_{CCh}$, proximal and distal to G-protein activation, are suppressed by caffeine. A major inhibition was observed at the proximal level.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.3
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• pp.349-360
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• 2018

Autophagy has been studied as a therapeutic strategy for cardiovascular diseases. However, insufficient studies have been reported concerning the influence of vascular smooth muscle cells (VSMCs) through autophagy regulation. The aim of the present study was to determine the effects of VSMCs on the regulation of autophagy under in vitro conditions similar to vascular status of the equipped micro-tubule target agent-eluting stent and increased release of platelet-derived growth factor-BB (PDGF-BB). Cell viability and proliferation were measured using MTT and cell counting assays. Immunofluorescence using an $anti-{\alpha}-tubulin$ antibody was performed to determine microtubule dynamic formation. Cell apoptosis was measured by cleavage of caspase-3 using western blot analysis, and by nuclear fragmentation using a fluorescence assay. Autophagy activity was assessed by microtubule-associated protein light chain 3-II (LC-II) using western blot analysis. Levels of intracellular reactive oxygen species (ROS) were measured using $H_2DCFDA$. The proliferation and viability of VSMCs were inhibited by microtubule regulation. Additionally, microtubule-regulated and PDGF-BB-stimulated VSMCs increased the cleavage of caspase-3 more than only the microtubule-regulated condition, similar to that of LC3-II, implying autophagy. Inhibitory autophagy of microtubule-regulated and PDGF-BB-stimulated VSMCs resulted in low viability. However, enhancement of autophagy maintained survival through the reduction of ROS. These results suggest that the apoptosis of conditioned VSMCs is decreased by the blocking generation of ROS via the promotion of autophagy, and proliferation is also inhibited. Thus, promoting autophagy as a therapeutic target for vascular restenosis and atherosclerosis may be a good strategy.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.1019-1030
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• 2003

Platycodi Radix, the root of Platycodon grandiflorum, commonly known as Doraji, is used as a traditional oriental medicine. Extracts from the roots of P. grandiflorum have been reported to have wide ranging health benefits. In the present study, we investigated the effects of an aqueous extract from the roots of P. grandiflorum (AEPG) on the growth of human lung carcinoma A549 cells. Results obtained are as fellow; AEPG treatment resulted in the inhibition of the cell viability of A549 cells in a concentration-dependent manner. Upon treatment with AEPG, A549 cells developed many of the hallmark features of apoptosis, including condensation of chromatin. Flow cytometry analysis confirmed that AEPG increased populations of apoptotic-sub G1 phase. Western blot and RT-PCR analyses indicated that the expressions of Bcl-2 was down-regulated but Bax was up-regulated in AEPG-treated A549 cells. AEPG-induced apoptotis of A549 cells was associated with rroteolytic cleavage and activation of caspase-3, release of cytochrome c from mitochondria into cytosol and down-regulation of Akt and phospho-Akt proteins in a dose-dependent manner. Induction of apoptosis by AEPG treatment was associated with inhibition and/or degradation of apoptotic target proteins such as poly(ADP-ribose) polymerase, β-catenin and phospholipase C-γ 1. AEPG treatment inhibited the levels of cyclooxygenases protein of A549 cells, which was associated with the inhibition of prostaglandin E2 accumulation in a concentration-dependent fashion. Taken together, these findings suggest that P. grandiflorum has strong potential for development as an agent for prevention against human lung cancer.

• Journal of Oriental Neuropsychiatry
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• v.25 no.4
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• pp.423-434
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• 2014

Objectives: Activated microglia cells play an important role in inflammatory responses in the central nervous system (CNS) which are involved in neurodegenerative diseases. We attempted to determine the anti-inflammatory effects of Cheongnoimyungshin-hwan (CNMSH) in microglia cells. Methods: We examined the effect of CNMSH on the inflammatory responses in BV2 microglia cells induced by lipopolysaccharide (LPS) and explored the mechanism underlying the action of CNMSH. Results: BV2 cells treated with LPS showed an up-regulation of nitric oxide (NO), prostaglandin $PGE_2(PGE_2)$ and interleukin $1{\beta}(IL-1{\beta})$ release, whereas CNMSH suppressed this up-regulation. CNMSH inhibited the induction of COX-2, iNOS and $IL-1{\beta}$ proteins in LPS-treated BV2 cells and blocked the LPS-induced phosphorylation and nuclear translocation of nuclear factor ${\kappa}B(NF-{\kappa}B$). Furthermore, CNMSH attenuated the LPS-induced phosphorylation of extracellular signal-regulated kinase and p38 mitogen activated protein kinase (MAPK), as well as the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, but did not inhibit the LPS-induced phosphorylation of c-Jun amino terminal kinase. Conclusions: These results suggest that the inhibitory effect of CNMSH on the LPS-induced production of inflammatory mediators and cytokines in BV2 cells is associated with the suppression of the $NF-{\kappa}B$ and PI3KAkt signaling pathways.

• Toxicological Research
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• v.12 no.1
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• pp.69-79
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• 1996

Primary culture of cerebellar neuronal cells derived from 8-day old Long-Evans rats was used. Pure granule cells, astrocytes or mixed cells culture systems were prepared. These cells were differentiated and developed synaptic connections. And the astrocytes were identified by immunostaining with glial fibrillary acidic protein (GFAP). Methamphetamine (MAP), which acts on dopaminergic system and cadmium (Cd), a toxic heavy metal, were applied and biochemical assays and electrophysiological studies were performed. $LC_50$ values estimated by MTT assay of MAP and Cd were 3 mM and 2$\mu M$ respectively. Cells were treated with 1 mM or 2 mM MAP and 1$\mu M$ $CdCl_2$ for 48 hour, and the incubation media were analyzed for the content of released LDH. MAP (2 mM) and Cd significantly increased the LDH release. Cell viability was decreased in both groups and some cytopathological changes like cell swelling or vacuolization were seen. The cerebellar granule cells were used for measuring membrane currents using whole-cell clamp technique. Sodium and potassium currents were not affected by MAP neither Cd, but calcium current was significantly reduced by Cd but not affected by MAP. Therefore, in vitro neurotoxicity test system using neuronaI cells and astrocytes cultures were established and can be used in screening of potential neurotoxic chemicals.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.443-448
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• 2010

Casein phosphopeptide (CPP) enhances calcium absorption in humans. Lactic acid bacteria (LAB) are capable of synthesis of cell-surface proteinase, which can hydrolyze milk protein and release several types of peptides in the medium. This study was conducted to characterize proteinase of LAB and to evaluate the CPP production from bovine milk. The content of CPP of milk produced by cell-free extract of LAB was determined based on the quantity of decomposed peptide from casein using the O-phthaldialdehyde (OPA) method. The proteolytic activity of LAB was assayed using fluorescein isothiocyanate (FITC)-labeled casein. Casein appeared to be a better substrate than whey proteins for extracellular proteinases of LAB. During fermentation, milk proteins were hydrolyzed by extracellular proteinase of LAB, resulting in an increase in the amount of free $NH_3$ groups. Overall, the results presented here indicate that CPP produced by LAB may be a promising material for novel applications in the dairy industry.