• Biomolecules & Therapeutics
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• 제27권4호
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• pp.373-380
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• 2019

Sphingosine kinase 1 and its product, sphingosine 1-phosphate (S1P), as well as their receptors, have been implicated in inflammatory responses. The functions of receptors $S1P_1$ and $S1P_2$ on cell motility have been investigated. However, the function of $S1P_3$ has been poorly investigated. In this study, the roles of $S1P_3$ on inflammatory response were investigated in primary peritoneal macrophages. $S1P_3$ receptor was induced along with sphingosine kinase 1 by stimulation of lipopolysaccharide (LPS). LPS treatment induced inflammatory genes, such iNOS, COX-2, $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. TY52156, an antagonist of $S1P_3$ suppressed the induction of inflammatory genes in a concentration dependent manner. Suppression of iNOS and COX-2 induction was further confirmed by western blotting and NO measurement. Suppression of $IL-1{\beta}$ induction was also confirmed by western blotting and ELISA. Caspase 1, which is responsible for $IL-1{\beta}$ production, was similarly induced by LPS and suppressed by TY52156. Therefore, we have shown $S1P_3$ induction in the inflammatory conditions and its pro-inflammatory roles. Targeting $S1P_3$ might be a strategy for regulating inflammatory diseases.

• 한국식품영양학회지
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• 제34권5호
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• pp.441-448
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• 2021

This study was designed to investigate the intracellular signaling pathways and immunoenhancing effect of macrophage activation by crude polysaccharides (CPP) extracted from citrus peels. CPP did not affect the cytotoxicity of RAW264.7 cells, but showed dose-dependent effects on cell viability. Also, CPP showed high production of chemokine (nitric oxide (NO)) and cytokines (interleukin (IL)-6 and tumor necrosis factor (TNF)-α). CPP increased IL-6, TNF-α, and inducible nitric oxide synthase (iNOS) mRNA expression dose-dependently. CPP also strongly induced the phosphorylation of the ERK, p38, and IκBα pathways in RAW 264.7 cells. In anti-pattern recognition receptors (PRRs) experiments, the effect of CPP on NO production was strongly suppressed by neutralizing toll-like receptor (TLR)2, TLR4, and Dectin1 antibodies, whereas IL-6 and TNF-α production by CPP was mainly suppressed by mannose receptor (MR). Therefore, these results suggest that CPP treatment-induced NO production was regulated by the ERK, p38, and NF-κB pathways through TLR2, TLR4, and Dectin1 receptors, whereas IL-6 and TNF-α production was primarily regulated by the ERK, p38, and NF-κB pathways through MR receptors.

• The Korean Journal of Physiology and Pharmacology
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• 제4권5호
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• pp.355-359
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• 2000

Cocaine induces immediate early gene expression and behavioral changes by blocking dopamine transporters in the terminals of nigrostriatal neurons in the striatum. The pharmacological role of serotonin 2/1C (5HT2/1C) receptors in cocaine-induced expression of zif268 (NGFI-A, egr1 and Krox-24) mRNA, a member of the zinc finger, was investigated using quantitative in situ hybridization histochemistry in vivo. Behavioral alterations induced by cocaine were also monitored in relation with blockade of the receptors. Systemic injection of ritanserin (1 mg/kg, s.c.), a 5HT2/1C receptor antagonist, did not reverse behavioral alterations and zif268 mRNA gene expression induced by 15 mg/kg cocaine, i.p., in the dorsal and ventral striatum. These data indicate that ritanserin-sensitive 5HT2/1C receptors are not necessary for cocaine-induced behavioral alterations and zif268 mRNA gene expression in the striatum.

• The Korean Journal of Physiology and Pharmacology
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• 제19권2호
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• pp.89-97
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• 2015

The aim of this study was to investigate the involvement of dopaminergic receptors (DR) in behavioral sensitization, as measured by locomotor activity, and the over-expression of cocaine- and amphetamine-regulated transcript (CART) peptides after repeated administration of cocaine in mice. Repeated administrations of cocaine induced behavioral sensitization and CART over-expression in mice. The levels of striatal CART mRNA were significantly increased on the $3^{rd}$ day. CART peptides were over-expressed on the $5^{th}$ day in the striata of behaviorally sensitized mice. A higher proportion of $CART^+$ cells in the cocaine-treated mice were present in the nucleus accumbens (NAc) shell than in the dorsolateral (DL) part of caudate putamen (CP). The concomitant administration of both $D_1R$ and $D_2R$ antagonists, SCH 23390 ($D_1R$ selective) and raclopride ($D_2R$ selective), blocked cocaine induced-behavioral sensitization, CART over-expression, and cyclic adenosine 5'-monophosphate (cAMP)/ protein kinase A (PKA)/phospho-cAMP response element-binding protein (pCREB) signal pathways. SCH 23390 more predominantly inhibited the locomotor activity, CART over-expression, pCREB and PKA activity than raclopride. Cocaine induced-behavioral sensitization was also attenuated in the both $D_1R$ and $D_2R$ knockout (KO) mice, respectively. CART over-expression and activated cAMP/PKA/pCREB signal pathways were inhibited in the $D_1R$-KO mice, but not in the $D_2R$-KO mice. It is suggested that behavioral sensitization, CART over-expression and activated cAMP/PKA/pCREB signal pathways induced by repeated administration of cocaine could be more predominantly mediated by $D_1R$.

• Journal of Gastric Cancer
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• 제6권3호
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• pp.132-138
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• 2006

목적: 도파민은 중추신경전달물질이지만 위장관에서 도파민수용체와 결합하여 점막상피세포 증식, 상피세포의 보호, 위암 세포증식과 관련이 있는 것으로 알려져 있다. 본 연구에서는 위암에서 기원한 세포주를 이용하여 도파민과 각각의 도파민 수용체가 위암 세포 증식과 억제에 작용하는 역할에 대해 알아보았다. 대상 및 방법: 위암세포기원에서 각각 유래한 세포주인 SNU601과 KCU-C2를 이용하여 RNA 추출 후 RT-PCR 시행 후 도파민수용체 D1, D2L과 D2S 각각에 대한 primer로 PCR을 시행하여 수용체 유전자의 상대적인 발현정도를 측정하였다. 도파민과 Dl 수용체의 대항제인 SCH 23390과 D2 수용체 대항제인 raclopride를 사용하여 약물처리에 따른 위암세포주에서 세포 증식에 대한 분석을 하였다. 결과: KCU-C2 세포주에서 D1과 D2L과 D2S 유전자 mRNA의 상대적인 발현정도는 모두 높은 발현을 보였지만, SNU 601 세포주에는 mRNA의 발현이 모두 낮은 수준이었으며, 특히 D2L mRNA는 발현되고 있지 않았다. 약물처리에 따른 위암세포주에서 세포증식에 대한 분석에서는 D1과 D2S 수용체를 통한 도파민의 신호는 세포의 증식을 억제하였고 D2L 수용체를 통한 도파민의 신호는 세포의 증식을 유도하였다. 결론: 본 연구를 통해 도파민이 위암의 세포증식과 억제에 관여하며, 도파민의 이러한 효과는 도파민의 신호가 어느 수용체를 통해 전달되었느냐에 따라 위암세포의 증식과 억제가 이루어짐을 알 수 있었다.

• Molecules and Cells
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• 제24권2호
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• pp.194-199
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• 2007

GCN4 is a typical eukaryotic transcriptional activator that is implicated in the expression of many genes involved in amino acids and purine biosyntheses under stress conditions. It is degraded by 26S proteasomes following ubiquitination. However, the immediate receptor for ubiquitinated Gcn4p has not yet been identified. We investigated whether ubiquitinated Gcn4p binds directly to Rpn10p as the ubiquitinated substrate receptor of the 26S proteasome. We found that the level of Gcn4p increased in cells deleted for Rpn10p but not in cells deleted for RAD23 and DSK2, the other ubiquitinated substrate receptors and, unlike Rpn10p, neither of these proteins recognized ubiquitinated Gcn4p. These results suggest that Rpn10p is the receptor that binds the polyubiquitin chain during ubiquitin-dependent proteolysis of Gcn4p.

• Journal of Animal Science and Technology
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• 제50권5호
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• pp.649-656
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• 2008

본 연구는 insulin-like growth factors(IGFs)가 돼지 지방전구세포의 증식과 분화에 미치는 작용기전을 구명하기 위해서 수행하였다. 지방전구세포는 갓난 암퇘지의 등지방에서 분리하였고, serum-deprived 조건하에서 IGFs와 mutant IGFs를 함유시켜 배양했는데 이 mutant IGFs는 IGF-Ⅰ에 비해 type-1 IGF receptor와 insulin receptor에 대한 친화력이 낮다. 50ng/ml의 IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27]IGF-Ⅱ를 배양중인 세포에 4일동안 처리했다. IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27]IGF-Ⅱ는 돼지 지방전구세포의 증식을 각각 39%, 8%, 25% 및 2% 촉진했다(증가된 세포수에 의해 측정). 이 사실은 IGF-Ⅰ과 IGF-Ⅱ는 type-1 IGF receptor 또는 insulin receptor에 결합을 통해서 지방세포의 증식 촉진을 가져왔음을 나타낸다. 그리고 IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27] IGF-Ⅱ는 지방전구세포의 분화를 50%, 17%, 37% 및 30% 각각 촉진시켰다(세포 분화는 glycerol- phosphate dehydrogenase 활성도에 의해 측정했다). IGF-Ⅰ의 type-1 IGF receptor 또는 insulin receptor에의 친화력이 낮아져서 세포 분화 촉진작용을 감소시킨 것이다. 그러나 [Leu27] IGF-Ⅱ의 분화촉진 작용은 IGF-Ⅱ의 그것에 비해 크게 차이가 나지 않았는데, 이 사실은 IGF-Ⅰ과 IGF-Ⅱ는 서로 다른 수용체－매개 작용기전에 의해 세포분화를 촉진시킴을 나타낸다. 즉 IGF-Ⅱ는 type-1 IGF receptor 또는 insulin receptor가 관여하지 않는 작용을 통해 돼지 지방전구세포의 분화를 촉진시켰다. 이 작용은 IGF-Ⅱ가 type-2 IGF receptor(또는 cation- independent mannose-6 phosphate receptor [CIM6P /IGF2 receptor])에 결합을 통해서 이뤄지는 것으로 여겨진다. 위의 결과는 IGF-Ⅱ가 CIM6P/ IGF2 receptor에의 결합을 통해 동물 지방전구세포의 분화를 촉진시킨다는 것을 밝혀낸 최초의 연구이다. 요약하면 이 본 연구는 IGF-Ⅰ과 IGF-Ⅱ는 서로 다른 세포내 receptor가 관여하는 작용기전을 통해 돼지 지방전구세포의 분화를 촉진함을 보여준다.

• The Korean Journal of Physiology and Pharmacology
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• 제7권2호
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• pp.59-63
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• 2003

The medial vestibular nucleus (MVN) neurons are controlled by excitatory synaptic transmission from the vestibular afferent and commissural projections, and by inhibitory transmission from interneurons. Spontaneous synaptic currents of MVN neurons were studied using whole cell patch clamp recording in slices prepared from 13- to 17-day-old rats. The spontaneous inhibitory postsynaptic currents (sIPSCs) were significantly reduced by the $GABA_A$ antagonist bicuculline ($20{\mu}M$), but were not affected by the glycine antagonist strychnine ($1{\mu}M$). The frequency, amplitude, and decay time constant of sIPSCs were $4.3{\pm}0.9$ Hz, $18.1{\pm}2.0$ pA, and $8.9{\pm}0.4$ ms, respectively. Spontaneous excitatory postsynaptic currents (sEPSCs) were mediated by non-NMDA and NMDA receptors. The specific AMPA receptor antagonist GYKI-52466 ($50{\mu}M$) completely blocked the non-NMDA mediated sEPSCs, indicating that they are mediated by an AMPA-preferring receptor. The AMPA mediated sEPSCs were characterized by low frequency ($1.5{\pm}0.4$ Hz), small amplitude ($13.9{\pm}1.9$ pA), and rapid decay kinetics ($2.8{\pm}0.2$ ms). The majority (15/21) displayed linear I-V relationships, suggesting the presence of GluR2-containing AMPA receptors. Only 35% of recorded MVN neurons showed NMDA mediated currents, which were characterized by small amplitude and low frequency. These results suggest that the MVN neurons receive excitatory inputs mediated by AMPA, but not kainate, and NMDA receptors, and inhibitory transmission mediated by $GABA_A$ receptors in neonatal rats.

• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.231-241
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• 2001

The mammalian cortical collecting duct (CCD) plays a major role in regulating renal NaCl reabsorption, which is important in $Na^+$ and $Cl^-$ homeostasis. The M-1 cell line, derived from the mouse cortical collecting duct, has been used as a mammalian model of the study on the electrolytes transport in CCD. M-1 cells were grown on collagen-coated permeable support and short circuit current $(I_{sc})$ was measured. M-1 cells developed amiloride-sensitive current $5{\sim}7$ days after seeding. Apical and basolateral addition of ATP induced increase in $I_{sc}$ in M-1 cells, which was partly retained in $Na^+-free$ or $Cl^--free$ solution, indicating that ATP increased $Na^+$ absorption and $Cl^-$ secretion in M-1 cells. $Cl^-$ secretion was mediated by the activation of apical cystic fibrosis transmembrane regulator (CFTR) chloride channels and $Ca^{2+}-activated$ chloride channels, but $Na^+$ absorption was not mediated by activation of epithelal sodium channel (ENaC). ATP increased cAMP content in M-1 cells. The RT-PCR analysis demonstrated that M-1 cells express $P2Y_2,\;P2X_3\;and\;P2Y_4$ receptors. These results showed that ATP regulates $Na^+$ and $Cl^-$ transports via multiple P2 purinoceptors on the apical and basolateral membranes in M-1 cells.

• 약학회지
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• 제35권5호
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• pp.394-400
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• 1991

A question whether abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steoid hormones in spontaneously hypertensive rats (SHR) exist was investigated. Four groups of experimental animals were prepared for SHR and normotensive Wistar rats (NW) respectively: 1) intact, 2) ovariectomized (OVX+V), 3) ovariectomized and estrogen treated (OVX+E), 4) ovariectomized and estrogen plus progesterone treated (OVX+E+P) groups. Hypothalami from experimental animals were dissected out and used for determination of .alpha.-adrenergic receptor binding characteristics and catecholamine contents. Norepinephrine(NE) content and B$_{max}$ of $\alpha_1$-adrenergic receptors in hypothalami were greater in intact SHR than in intact NW, but dopamine(DA) content was lower in SHR than in NW. Neither contents of NE and DA nor binding characteristics of $\alpha_1$-adrenergic receptors were different in OVX+V and OVX+E group from intact group of both SHR and NW. Kd and B$_{max}$ of $\alpha_1$-adrenergic receptors in OVX+E+P was lower than that in intact SHR but not in NW. DA content was lower in OVX+E+P than in intact group of SHR and NW. The result of the present study indicates that there is an abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steroid hormones in SHR which may be one of genetically-determined factors probably not responsible for the development of hypertension.