• BMB Reports
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• v.46 no.2
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• pp.103-106
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• 2013

Phosphoinositide 3-kinases (PI3Ks) play key roles in synaptic plasticity and cognitive functions in the brain. We recently found that genetic deletion of $PI3K{\gamma}$, the only known member of class IB PI3Ks, results in impaired N-methyl-D-aspartate receptor-dependent long-term depression (NMDAR-LTD) in the hippocampus. The activity of RalA, a small GTP-binding protein, increases following NMDAR-LTD inducing stimuli, and this increase in RalA activity is essential for inducing NMDAR-LTD. We found that RalA activity increased significantly in $PI3K{\gamma}$ knockout mice. Furthermore, NMDAR-LTD-inducing stimuli did not increase RalA activity in $PI3K{\gamma}$ knockout mice. These results suggest that constitutively increased RalA activity occludes further increases in RalA activity during induction of LTD, causing impaired NMDAR-LTD. We propose that $PI3K{\gamma}$ regulates the activity of RalA, which is one of the molecular mechanisms inducing NMDAR-dependent LTD.

• The Korea Journal of Herbology
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• v.30 no.1
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• pp.85-93
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• 2015

Objectives : Bilobalide (BIL) is a predominant sesquiterpene trilactone constituent that accounts for a partial portion of the standardized Ginkgonis Folium extract, which has been widely used to treat a variety of neurological disorders involving cerebral ischemia and neurodegeneration. In this study, it was tested whether BIL exhibits anti-inflammatory activities on inflammation response, or not. Methods : To elucidate the molecular mechanisms of BIL on pharmacological and biochemical actions in inflammation, we examined the effect of BIL on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated macrophages. The investigation was focused on how BIL affect on inflammation-related mediators including various signals such as nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), inducible NO synthase(iNOS), cyclooxygenase-2(COX-2), interleukin-6(IL-6), tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), mitogen-activated protein kinases(MAPKs) and nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) in LPS-stimulated RAW 264.7 cells. Results : We found that BIL inhibited LPS-induced NO, $PGE_2$, IL-6 and $TNF-{\alpha}$ productions as well as the expressions of iNOS and COX-2. Furthermore, BIL suppressed the LPS-induced phosphorylation for MAPK activation. Conclusions : These results suggest that BIL has inhibitory effects on LPS-induced $PGE_2$, NO, IL-6 and $TNF-{\alpha}$ production, as well as the expressions of iNOS and COX-2 in the murine macrophage. It seems that these inhibitory effects occur by blocking the phosphorylation of MAPKs for activation. Then, BIL suppressed the activation of nuclear factor $NF-{\kappa}B$ in nucleus. These observations suggest that BIL has anti-inflammatory effect by inhibiting.

• Korean Journal of Medicinal Crop Science
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• v.22 no.6
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• pp.449-456
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• 2014

Anti-inflammatory activity of the extracts of ginseng berry (GBE) was investigated through the evaluation of its inhibitory effect on the production of inflammatory meditator, nitric oxide(NO), tumor necrocis factor-alpha (TNF-${\alpha}$), interleukin-6 (IL-6) in LPS-induced RAW264.7 macrophage cells. GBE was fractionated using n-hexane, chloroform, ethylacetate, buthanol and $H_2O$, sequentially. RAW264.7 cells were induced $100ng/m{\ell}$ of lipopolysaccharide (LPS) and treated with 0, 1.6, 8, 40 and $200{\mu}g/m{\ell}$ of GBE fractions. LPS-induced NO production on all of GBE fractions was inhibited with increasing added concentration of GBE fractions. Chloroform fraction of GBE was the most effective in inhibiting LPS-induced TNF-${\alpha}$ production. Hexane, chloroform and $H_2O$ fractions of GBE exhibit strong inhibition LPS-induced IL-6 production. Especially, $H_2O$ fractions of GBE was the most effective in inhibiting LPD-induced IL-6 production without significant cytotoxicity in RAW264.7 cells, and reduced the activation of mitogen-activated protein kinases (MAPK) and IkB phosphorylation. These results indicate that $H_2O$ fractions of GBE exhibits strong anti-inflammatory effects by inhibition of NF-kB by inhibition of p-38 on MAPK and IkB phosphorylation.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.9-17
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• 2004

Objective : Mesangial cell proliferation and excessive accumulation of extracellular matrix (ECM) proteins is the common pathologic feature of glomerulosclerosis, and platelet-derived growth factor (PDGF) BB-chain, transforming growth factor betal $(TGF-{\beta}1)$, cyclin dependent kinases (CDK) and CDK inhibitors mediated in these pathophysiological processes. Bupleurum falcatum which is one of the most widely used components in traditional oriental medicines, has multiple pharmacological effects, such as antipyretic, analgesic, immune modulating, anti-inflammatory, anti-allergic, anti-thrombotic, anti-atherosclerotic, and antitussive effects. Methods : In this study, we evaluated the influence of Bupleurum falcatum on mesangial cell proliferation, DNA synthesis and expression of PDGF-BB chain, $TGF-{\beta}1$, CDKI, CDK2, CDK4, p21 and p27 in fetal bovine serum (FBS)-activated human mesangial cell. Results : Bupleurum falcatum reduced the mesangial cell proliferation and DNA synthesis more than control and captopril. And in the ELISA analysis of $TGF-{\beta}1$, and RT-PCR of PDGF-BB chain, CDK1, CDK2, CDK4, p21, and p27, Bupleurum falcatum inhibited the expression of $TGF-{\beta}1$ protein and PDGF-BB, CDK1, CDK2 gene and promoted that of p21 gene in a dose-dependent manner in comparing with control and captopril. Conclusions: These results suggest that Bupleurum falcatum may inhibit the mesangial cell proliferation and DNA synthesis by regulation of PDGF-BB and $TGF-{\beta}1$ expressions, and by modulation of CDK1, CDK2 and p21 expression.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.2
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• pp.131-136
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• 2016

An ethanolic extracts of Scutellaria Baicalensis GEORGI are used to treat cancer, infectious diseases, and inflammation. In the present study, we investigated the effects of an ESBG on the growth and survival of 5637 cells, a human bladder carcinoma cell line. Cells were treated with different concentrations of an ethanolic extract of Scutellaria Baicalensis GEORGI (ESBG), and cell death was assessed using a MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay. Analyses of the sub G1 peak, caspase-3 and -9 activities, and mitochondrial membrane depolarizations were conducted to confirm cell death by apoptosis. ESBG had a cytotoxic effect on 5637 cells, and increased the sub G1 peak, caspase-3 and -9 activities, and mitochondrial depolarization, indicating ESBG induced apoptosis. Furthermore, MAPK (mitogen-activated protein kinases) inhibitors suppressed this apoptosis. In an in vitro study, a combination of sub-optimal doses of ESBG and paclitaxel, 5-fluorouracil, or docetaxel noticeably suppressed tumor growth by 5637 cells. Our findings provide insight of the mechanisms underlying cellular apoptosis induced by ESBG, and suggest new therapeutic strategies for bladder cancer.

• Natural Product Sciences
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• v.24 no.1
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• pp.28-35
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• 2018

Pulegone is a naturally occurring organic compound obtained from essential oils from a variety of plants. The aim of this study was to investigate the anti-inflammatory effects through the inhibitory mechanism of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), nuclear factor kappa B ($NF-{\kappa}B$), mitogen-activated protein kinases (MAPK) pathways and the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase (HO)-1 pathways in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Results revealed that pulegone significantly inhibited NO production as well as iNOS and COX-2 expressions. Meanwhile, western blot analysis showed that pulegone down-regulated LPS-induced $NF-{\kappa}B$ and MAPKs activation in RAW 264.7 cells. Furthermore, the selected compound suppressed LPS-induced intracellular ROS production in RAW 264.7 cells, while the expression of stress response gene, HO-1, and its transcriptional activator, Nrf-2 was upregulated upon pulegone treatment. Taking together, these findings provided that pulegone inhibited the LPS-induced expression of inflammatory mediators via the down-regulation iNOS, COX-2, $NF-{\kappa}B$, and MAPKs signaling pathways as well as up-regulation of Nrf-2/HO-1 indicating that pulegone has a potential therapeutic and preventive application in various inflammatory diseases.

• Natural Product Sciences
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• v.24 no.1
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• pp.13-20
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• 2018

Estragole is a naturally occurring phenylpropanoid obtained from essential oils found in a broad diversity of plants. Although the phenylpropanoids show many biological activities, clear regulation of the inflammatory signaling pathways has not yet been determined. Here, we scrutinized the anti-inflammatory effect of estragole. The anti-inflammatory effect of estragole was determined through the inhibitory mechanisms of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), nuclear factor kappa B ($NF-{\kappa}B$), and mitogen-activated protein kinases (MAPK) pathways and the activation of nuclear factor erythroid 2-related factor 2 (Nrf-2)/heme oxygenase (HO)-1 pathways in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Estragole significantly inhibited NO production, iNOS and COX-2 expression as well as LPS-induced $NF-{\kappa}B$ and MAPK activation. Furthermore, estragole suppressed LPS-induced intracellular ROS production but up-regulated the stress response gene HO-1 via the activation of transcription factor Nrf-2. These findings demonstrate that estragole inhibits the LPS-induced expression of inflammatory mediators via the down-regulation of iNOS, COX-2, $NF-{\kappa}B$, and MAPK pathways, as well as the up-regulation of the Nrf-2/HO-1 pathway, indicating that this phenylpropanoid has potential therapeutic and preventive applications in various inflammatory diseases.

• Molecules and Cells
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• v.25 no.4
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• pp.479-486
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• 2008

Mitogen-activated protein kinases (MAPKs) play an indispensable role in activation of the myogenic program, which is responsive to mechanical stimulation. Although there is accumulating evidence of mechanical force-mediated cellular responses, the role of MAPK in regulating the myogenic process in myoblasts exposed to cyclic stretch is unclear. Cyclic stretch induced the proliferation of C2C12 myoblasts and inhibited their differentiation into myotubes. In particular, it induced persistent phosphorylation of p38 kinase, and decreased the level of phosphorylation of extracellular-signal regulated kinase (ERK). Partial inhibition of p38 phosphorylation increased cellular levels of MyoD and p-ERK in stretched C2C12 cells, along with increased myotube formation. Treatment with $10{\mu}M$ PD98059 prevented myogenin expression in response to a low dose of SB203580 ($3{\mu}M$) in the stretched cells, suggesting that adequate ERK activation is also needed to allow the cells to differentiate into myotubes. These results suggest that cyclic stretch inhibits the myogenic differentiation of C2C12 cells by activating p38-mediated signaling and inhibiting ERK phosphorylation. We conclude that p38 kinase, not ERK, is the upstream signal transducer regulating cellular responses to mechanical stretch in skeletal muscle cells.

• Molecules and Cells
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• v.40 no.10
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• pp.761-772
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• 2017

Glioblastoma is the most frequent and most aggressive brain tumor in adults. Solute carrier family 8 member 2 (SLC8A2) is only expressed in normal brain, but not present in other human normal tissues or in gliomas. Therefore, we hypothesized that SLC8A2 might be a glioma tumor suppressor gene and detected the role of SLC8A2 in glioblastoma and explored the underlying molecular mechanism. The glioblastoma U87MG cells stably transfected with the lentivirus plasmid containg SLC8A2 (U87MG-SLC8A2) and negative control (U87MG-NC) were constructed. In the present study, we found that the tumorigenicity of U87MG in nude mice was totally inhibited by SLC8A2. Overexpression of SLC8A2 had no effect on cell proliferation or cell cycle, but impaired the invasion and migration of U87MG cells, most likely through inactivating the extracellular signal-related kinases (ERK)1/2 signaling pathway, inhibiting the nuclear translocation and DNA binding activity of nuclear factor kappa B ($NF-{\kappa}B$), reducing the level of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA)-its receptor (uPAR) system (ERK1/2-$NF-{\kappa}B$-MMPs/uPA-uPAR), and altering the protein levels of epithelial to mesenchymal transitions (EMT)-associated proteins E-cardherin, vimentin and Snail. In addition, SLC8A2 inhibited the angiogenesis of U87MG cells, probably through combined inhibition of endothelium-dependent and endothelium-nondependent angiogenesis (vascular mimicry pattern). Totally, SLC8A2 serves as a tumor suppressor gene and inhibits invasion, angiogenesis and growth of glioblastoma.

• Natural Product Sciences
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• v.14 no.1
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• pp.21-26
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• 2008

The leaves of Acanthopanax species have traditionally been used as a tonic and a sedative as well as in the treatment of rheumatism and diabetes. Chiisanoside is the major active lupane triterpenoid of Acanthopanax leaves. To investigate the bioactivities of chiisanoside, which act on bone metabolism, the effects of chiisanoside on the function of osteoblastic MC3T3-E1 cells were studied. Chiisanoside $(0.02{\sim}20\;{\mu}M)$ significantly increased the growth of MC3T3-E1 cells and caused a significant elevation of alkaline phosphatase (ALP) activity, collagen content, and nodules mineralization in the cells (P < 0.05). The effect of chiisanoside (2 ${\mu}M$) in increasing ALP activity was completely prevented by the presence of tamoxifen, suggesting that the effect of chiisanoside might be partly estrogen receptor mediated. Moreover, cotreatment of p38 inhibitor SB203580 or JNK inhibitor SP600125 inhibited chiisanoside-mediated ALP upregulation, suggesting that the induction of differentiation by chiisanoside is associated with increased activation of p38 and JNK mitogen-activated protein kinases. Our data indicate that the enhancement of osteoblast function by chiisanoside may result in the prevention for osteoporosis.