• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.138-148
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• 2018

Objective: Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEN), common contaminants in the feed of farm animals, cause immune function impairment and organ inflammation. Consequently, the main objective of this study was to elucidate DON and ZEN effects on the mRNA expression of pro-inflammatory cytokines and other immune related genes in the kidneys of piglets. Methods: Fifteen 6-week-old piglets were randomly assigned to three dietary treatments for 4 weeks: control diet, and diets contaminated with either 8 mg DON/kg feed or 0.8 mg ZEN/kg feed. Kidney samples were collected after treatment, and RNA-seq was used to investigate the effects on immune-related genes and gene networks. Results: A total of 186 differentially expressed genes (DEGs) were screened (120 upregulated and 66 downregulated). Gene ontology analysis revealed that the immune response, and cellular and metabolic processes were significantly controlled by these DEGs. The inflammatory stimulation might be an effect of the following enriched Kyoto encyclopedia of genes and genomes pathway analysis found related to immune and disease responses: cytokine-cytokine receptor interaction, chemokine signaling pathway, toll-like receptor signaling pathway, systemic lupus erythematosus (SLE), tuberculosis, Epstein-Barr virus infection, and chemical carcinogenesis. The effects of DON and ZEN on genome-wide expression were assessed, and it was found that the DEGs associated with inflammatory cytokines (interleukin 10 receptor, beta, chemokine [C-X-C motif] ligand 9, CXCL10, chemokine [C-C motif] ligand 4), proliferation (insulin like growth factor binding protein 4, IgG heavy chain, receptor-type tyrosine-protein phosphatase C, cytochrome P450 1A1, ATP-binding cassette sub-family 8), and other immune response networks (lysozyme, complement component 4 binding protein alpha, oligoadenylate synthetase 2, signaling lymphocytic activation molecule-9, ${\alpha}$-aminoadipic semialdehyde dehydrogenase, Ig lambda chain c region, pyruvate dehydrogenase kinase, isozyme 4, carboxylesterase 1), were suppressed by DON and ZEN. Conclusion: In summary, our results indicate that high concentrations of DON and ZEN suppress the inflammatory response in kidneys, leading to potential effects on immune homeostasis.

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.120-122
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• 2007

All living organisms use numerous signal-transduction pathways to sense and respond to their environments and thereby survive and proliferate in a range of biological niches. Molecular dissection of these signalling networks has increased our understanding of these communication processes and provides a platform for therapeutic intervention when these pathways malfunction in disease states, including infection. Owing to the expanding availability of sequenced genomes, a wealth of genetic and molecular tools and the conservation of signalling networks, members of the fungal kingdom serve as excellent model systems for more complex, multicellular organisms. Here, we employed Cryptococcus neoformans as a model system to understand how fungal-signalling circuits operate at the molecular level to sense and respond to a plethora of environmental stresses, including osmoticshock, UV, high temperature, oxidative stress and toxic drugs/metabolites. The stress-activated p38/Hog1 MAPK pathway is structurally conserved in many organisms as diverse as yeast and mammals, but its regulation is uniquely specialized in a majority of clinical Cryptococcus neoformans serotype A and D strains to control differentiation and virulence factor regulation. C. neoformans Hog1 MAPK is controlled by Pbs2 MAPK kinase (MAPKK). The Pbs2-Hog1 MAPK cascade is controlled by the fungal "two-component" system that is composed of a response regulator, Ssk1, and multiple sensor kinases, including two-component.like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. We also identified and characterized the Ssk2 MAPKKK upstream of the MAPKK Pbs2 and the MAPK Hog1 in C. neoformans. The SSK2 gene was identified as a potential component responsible for differential Hog1 regulation between the serotype D sibling f1 strains B3501 and B3502 through comparative analysis of their meiotic map with the meiotic segregation of Hog1-dependent sensitivity to the fungicide fludioxonil. Ssk2 is the only polymorphic component in the Hog1 MAPK module, including two coding sequence changes between the SSK2 alleles in B3501 and B3502 strains. To further support this finding, the SSK2 allele exchange completely swapped Hog1-related phenotypes between B3501 and B3502 strains. In the serotype A strain H99, disruption of the SSK2 gene dramatically enhanced capsule biosynthesis and mating efficiency, similar to pbs2 and hog1 mutations. Furthermore, ssk2, pbs2, and hog1 mutants are all hypersensitive to a variety of stresses and completely resistant to fludioxonil. Taken together, these findings indicate that Ssk2 is the critical interface protein connecting the two-component system and the Pbs2-Hog1 pathway in C. neoformans.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.427-436
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• 2005

Objective: MMP-8 is a neutrophil enzyme and its level increases in some inflammatory diseases, including periodontal disease. We knew that the lipopolysaccharide of E.coli(E-LPS) induced MMP-8 release from human neutrophils. E-LPS is known to induce the production and release of inflammatory cytokines through CD14, Toll-like receptor(TLR). In the present study, we investigated whether MMP-8 release by E-LPS is induced via CD14-TLR pathway and the cellular mechanism of MMP-8 release in human neutrophils. Material and methods: Human neutrophils were isolated from the peripheral blood of healthy donors and pre-incubated in medium containing antibodies against CD14, anti-TLR2 and anti-TLR4 or several inhibitors of microtubules and microfilaments and then incubated with E-LPS. The cells were treated TPCK and E-LPS simultaneously. The MMP-8amount in the culture medium was determined using ELISA. Results: E-LPS increased MMP-8release from neutrophils and its induction was inhibited by anti-CD14 and anti-TLR4 but not by anti-TLR2 antibodies. The inhibitors of microtubule and microfilament polymerization significantly decreased E-LPS-induced MMP-8release. TPCK inhibited E-LPS-induced MMP-8 release. Conclusion: These results suggest that MMP-8 release is induced by E-LPS via the CD14-TLR4 signal pathway in human neutrophils and may be depedent on microtubule and microfilament systems and $NF-{\kappa}B$ pathway.

• Molecules and Cells
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• v.41 no.5
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• pp.423-435
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• 2018

This investigation was aimed at working out the combined role of lncRNA H19, miR-29b and Wnt signaling in the development of colorectal cancer (CRC). In the aggregate, 185 CRC tissues and corresponding para-carcinoma tissues were gathered. The human CRC cell lines (i.e. HT29, HCT116, SW480 and SW620) and normal colorectal mucosa cell line (NCM460) were also purchased. Si-H19, si-NC, miR-29b-3p mimics, miR-29b-3p inhibitor, si-PGRN and negative control (NC) were, respectively, transfected into the CRC cells. Luciferase reporter plasmids were prepared to evaluate the transduction activity of $Wnt/{\beta}-catenin$ signaling pathway, and dual-luciferase reporter gene assay was arranged to confirm the targeted relationship between H19 and miR-29b-3p, as well as between miR-29b-3p and PGRN. Finally, the proliferative and invasive capacities of CRC cells were appraised through transwell, MTT and scratch assays. As a result, overexpressed H19 and down-expressed miR-29b-3p displayed close associations with the CRC patients' poor prognosis (P < 0.05). Besides, transfection with si-H19, miR-29b-3p mimic or si-PGRN were correlated with elevated E-cadherin expression, decreased snail and vimentin expressions, as well as less-motivated cell proliferation and cell metastasis (P < 0.05). Moreover, H19 was verified to directly target miR-29b-3p based on the luciferase reporter gene assay (P < 0.05), and miR-29b-3p also bound to PGRN in a direct manner (P < 0.05). Finally, addition of LiCl ($Wnt/{\beta}-catenin$ pathway activator) or XAV93920 ($Wnt/{\beta}-catenin$ pathway inhibitor) would cause remarkably altered E-cadherin, c-Myc, vimentin and snail expressions, as well as significantly changed transcriptional activity of ${\beta}-catenin/Tcf$ reporter plasmid (P < 0.05). In conclusion, the lncRNA H19/miR-29b-3p/PGRN/Wnt axis counted a great deal for seeking appropriate diagnostic biomarkers and treatment targets for CRC.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.297-305
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• 1998

This study used in vivo intracellular recording in rat hippocampus to evaluate the effect of lidocaine and MK-801 on the membrane properties and the synaptic responses of individual neurons to electrical stimulation of the commissural pathway. Cells in control group typically fired in a tonic discharge mode with an average firing frequency of $2.4{\pm}0.9$ Hz. Neuron in MK-801 treated group (0.2 mg/kg, i.p.) had an average input resistance of $3.28{\pm}5.7\;M{\Omega}$ and a membrane time constant of $7.4{\pm}1.8$ ms. These neurons exhibited $2.4{\pm}0.2$ ms spike durations, which were similar to the average spike duration recorded in the neurons of the control group. Slightly less than half of these neurons were firing spontaneously with an average discharge rate of $2.4{\pm}1.1$ Hz. The average peak amplitude of the AHP following the spikes in these groups was $7.4{\pm}0.6$ mV with respect to the resting membrane potential. Cells in MK-801 and lidocaine treated group (5 mg/kg, i.c.v.) had an average input resistance of $3.45{\pm}6.0\;M{\Omega}$ and an average time constant of $8.0{\pm}1.4$ ms. The cells were firing spontaneously at an average discharge rate of $0.6{\pm}0.4$ Hz. Upon depolarization of the membrane by 0.8 nA for 400 ms, all of the tested cells exhibited accommodation of spike discharge. The most common synaptic response contained an EPSP followed by early-IPSP and late-IPSP. Analysis of the voltage dependence revealed that the early-IPSP and late-IPSP were putative $Cl^--and\;K^+-dependent$, respectively. Systemic injection of the NMDA receptor blocker, MK-801, did not block synaptic responses to the stimulation of the commissural pathway. No significant modifications of EPSP, early-IPSP, or late-IPSP components were detected in the MK-801 and/or lidocaine treated group. These results suggest that MK-801 and lidocaine manifest their CNS effects through firing pattern of hippocampal pyramidal cells and neural network pattern by changing the synaptic efficacy and cellular membrane properties.

• Toxicological Research
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• v.27 no.4
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• pp.253-259
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• 2011

Transforming growth factor ${\beta}$ (TGF-${\beta}$) is involved in cellular processes including growth, differentiation, apoptosis, migration, and homeostasis. Generally, TGF-${\beta}$ is the inhibitor of cell cycle progression and plays a role in enhancing the antagonistic effects of many growth factors. Unlike the antiproliferative effect of TGF-${\beta}$, E2, an endogeneous estrogen, is stimulating cell proliferation in the estrogen-dependent organs, which are mediated via the estrogen receptors, $ER{\alpha}$ and $ER{\beta}$, and may be considered as a critical risk factor in tumorigenesis of hormone-responsive cancers. Previous researches reported the cross-talk between estrogen/$ER{\alpha}$ and TGF-${\beta}$ pathway. Especially, based on the E2-mediated inhibition of TGF-${\beta}$ signaling, we examined the inhibition effect of 4-tert-octylphenol (OP) and 4-nonylphenol (NP), which are well known xenoestrogens in endocrine disrupting chemicals (EDCs), on TGF-${\beta}$ signaling via semi-quantitative reverse-transcription PCR. The treatment of E2, OP, or NP resulted in the downregulation of TGF-${\beta}$ receptor2 (TGF-${\beta}$ R2) in TGF-${\beta}$ signaling pathway. However, the expression level of TGF-${\beta}1$ and TGF-${\beta}$ receptor1 (TGF-${\beta}$ R1) genes was not altered. On the other hand, E2, OP, or NP upregulated the expression of a cell-cycle regulating gene, c-myc, which is a oncogene and a downstream target gene of TGF-${\beta}$ signaling pathway. As a result of downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc, E2, OP, or NP increased cell proliferation of BG-1 ovarian cancer cells. Taken together, these results suggest that E2 and these two EDCs may mediate cancer cell proliferation by inhibiting TGF-${\beta}$ signaling via the downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc oncogene. In addition, it can be inferred that these EDCs have the possibility of tumorigenesis in estrogen-responsive organs by certainly representing estrogenic effect in inhibiting TGF-${\beta}$ signaling.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.66-83
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• 2002

Recently, we have provided evidence that ginsenosides, the active components of Panax ginseng, utilize pertussis toxin (PTX)-insensitive $G{\alpha}_{q/11}-phospholipase\;C-{\beta}3(PLC-{\beta}3)$ signal transduction pathway for the enhancement of $Ca^{2+}-activated\;Cl^{-}$ current in the Xenopus oocyte (British J. Pharmacol. 132, 641-647, 2001; JBC 276, 48797-48802, 2001). Other investigators have shown that stimulation of receptors linked to $G{\alpha}-PLC$ pathway inhibits the activity of G proteincoupled inwardly rectifying $K^+$ (GIRK) channel. In the present study, we sought to determine whether ginsenosides influenced the activity of GIRK 1 and GIRK 4 (GIRK 1/4) channels expressed in the Xenopus oocyte, and if so, the underlying signal transduction mechanism. In oocyte injected with GIRK 1/4 channel cRNAs, bath-applied ginsenosides inhibited high potassium (HK) solution-elicited GIRK current $(EC_{50}:4.9{\pm}4.3\;{\mu}g/ml).$ Pretreatment of the oocyte with PTX reduced the HK solution-elicited GIRK current by $49\%,$ but it did not alter the inhibitory ginsenoside effect on GIRK current. Prior intraoocyte injection of cRNA(s) coding $G{\alpha}_q,\;G{\alpha}_{11}\;or\;G{\alpha}_q/G{\alpha}_{11},\;but\;not\;G{\alpha}_{i2}\;or\;G{\alpha}_{oA}$ attenuated the inhibitory ginsenoside effect. Injection of cRNAs coding $G{\beta}_{1{\gamma}2}$ also attenuated the ginsenoside effect. Similarly, injection of the cRNAs coding regulators of G protein signaling 1, 2 and 4 (RGS1, RGS2 and RGS4), which interact with $G{\alpha}_i\;and/or\;G{\alpha}_{q/11}$ and stimulates the hydrolysis of GTP to GDP in active GTP-bound $G{\alpha}$ subunit, resulted in a significant reduction of ginsenoside effect on GIRK current. Preincubation of GIRK channel-expressing oocyte in PLC inhibitor (U73122) or protein kinase C (PKC) inhibitor (staurosporine or chelerythrine) blocked the inhibitory ginsenoside effect on GIRK current. On the other hand, intraoocyte injection of BAPTA, a free $Ca^{2+}$ chelator, had no significant effect on the ginsenoside action. Taken together, these results suggest that ginsenosides inhibit the activity of GIRK 1/4 channel expressed in the Xenopus oocyte through a PTX-insensitive and $G{\alpha}_{q/11}$-,PLC-and PKC-mediated signal transduction pathway.

• Molecules and Cells
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• v.41 no.12
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• pp.1008-1015
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• 2018

$I{\kappa}B$, a cytoplasmic inhibitor of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$), is reportedly degraded via the proteasome. However, we recently found that long-term incubation with proteasome inhibitors (PIs) such as PS-341 or MG132 induces $I{\kappa}B{\alpha}$ degradation via an alternative pathway, lysosome, which results in $NF-{\kappa}B$ activation and confers resistance to PI-induced lung cancer cell death. To enhance the anti-cancer efficacy of PIs, elucidation of the regulatory mechanism of PI-induced $I{\kappa}B{\alpha}$ degradation is necessary. Here, we demonstrated that PI up-regulates nuclear factor (erythroid-derived 2)-like 2 (Nrf2) via both de novo protein synthesis and Kelch-like ECH-associated protein 1 (KEAP1) degradation, which is responsible for $I{\kappa}B{\alpha}$ degradation via macroautophagy activation. PIs increased the protein level of light chain 3B (LC3B, macroautophagy marker), but not lysosome-associated membrane protein 2a (Lamp2a, the receptor for chaperone-mediated autophagy) in NCI-H157 and A549 lung cancer cells. Pretreatment with macroautophagy inhibitor or knock-down of LC3B blocked PI-induced $I{\kappa}B{\alpha}$ degradation. PIs up-regulated Nrf2 by increasing its transcription and mediating degradation of KEAP1 (cytoplasmic inhibitor of Nrf2). Overexpression of dominant-negative Nrf2, which lacks an N-terminal transactivating domain, or knock-down of Nrf2 suppressed PI-induced LC3B protein expression and subsequent $I{\kappa}B{\alpha}$ degradation. Thus, blocking of the Nrf2 pathway enhanced PI-induced cell death. These findings suggest that Nrf2-driven induction of LC3B plays an essential role in PI-induced activation of the $I{\kappa}B$/$NF-{\kappa}B$ pathway, which attenuates the anti-tumor efficacy of PIs.

• BMB Reports
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• v.48 no.6
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• pp.303-312
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• 2015

Receptor-interacting protein kinase-3 (RIP3, or RIPK3) is an essential protein in the "programmed", or "regulated" necrosis cell death pathway that is activated in response to death receptor ligands and other types of cellular stress. Programmed necrotic cell death is distinguished from its apoptotic counterpart in that it is not characterized by the activation of caspases; unlike apoptosis, programmed necrosis results in plasma membrane rupture, thus spilling the contents of the cell and triggering the activation of the immune system and inflammation. Here we discuss findings, including our own recent data, which show that RIP3 protein expression is absent in many cancer cell lines. The recent data suggests that the lack of RIP3 expression in a majority of these deficient cell lines is due to methylation-dependent silencing, which limits the responses of these cells to pro-necrotic stimuli. Importantly, RIP3 expression may be restored in many cancer cells through the use of hypomethylating agents, such as decitabine. The potential implications of loss of RIP3 expression in cancer are explored, along with possible consequences for chemotherapeutic response. [BMB Reports 2015; 48(6): 303-312]

• Physical Therapy Rehabilitation Science
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• v.1 no.1
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• pp.6-12
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• 2012

Objective: Coenzyme (CoQ10) is an enzymatic co factor used in normal cellular metabolism. Recent evidence shows that in people with heart disease it can reverse endothelial cell damage in the blood vessels. It is also a potent antioxidant. Design: One group pretest-posttest design. Methods: In the present study, endothelial function was evaluated using the response to occlusion and heat before and 2 weeks after administration of CoQ10, 300 mg/day. Thirty Eight subjects, who are physical therapy students, participated in a series of experiments to see if taking 300 mg of CoQ10 daily for 2 weeks would impact resting blood flow in the forearm skin and the blood flow response to 4 minutes of vascular occlusion and the response to local heat ($42^{\circ}C$) for 6 minutes. Results: The results showed that, for this population, there was no difference in the response to heat. However, the response to occlusion was improved after administration of CoQ10. Conclusions: It would appear that in a young population CoQ10 has no effect on the nitric oxide vasodilator pathway in skin but does influence other vasodilator pathways.