• The Korean Journal of Physiology and Pharmacology
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• v.20 no.6
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• pp.581-593
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• 2016

The advantages of monounsaturated fatty acids (MUFAs) on insulin resistance and type 2 diabetes mellitus (T2DM) have been well established. However, the molecular mechanisms of the anti-diabetic action of MUFAs remain unclear. This study examined the anti-hyperglycemic effect and explored the molecular mechanisms involved in the actions of fish oil- rich in MUFAs that had been acquired from hybrid catfish (Pangasius larnaudii${\times}$Pangasianodon hypophthalmus) among experimental type 2 diabetic rats. Diabetic rats that were fed with fish oil (500 and 1,000 mg/kg BW) for 12 weeks significantly reduced the fasting plasma glucose levels without increasing the plasma insulin levels. The diminishing levels of plasma lipids and the muscle triglyceride accumulation as well as the plasma leptin levels were identified in T2DM rats, which had been administrated with fish oil. Notably, the plasma adiponectin levels increased among these rats. The fish oil supplementation also improved glucose tolerance, insulin sensitivity and pancreatic histological changes. Moreover, the supplementation of fish oil improved insulin signaling ($p-Akt^{Ser473}$ and p-PKC-${\zeta}/{\lambda}^{Thr410/403}$), $p-AMPK^{Thr172}$ and membrane GLUT4 protein expressions, whereas the protein expressions of pro-inflammatory cytokines (TNF-${\alpha}$ and nuclear NF-${\kappa}B$) as well as p-PKC-${\theta}^{Thr538}$ were down regulated in the skeletal muscle. These data indicate that the effects of fish oil-rich in MUFAs in these T2DM rats were partly due to the attenuation of insulin resistance and an improvement in the adipokine imbalance. The mechanisms of the anti-hyperglycemic effect are involved in the improvement of insulin signaling, AMPK activation, GLUT4 translocation and suppression of pro-inflammatory cytokine protein expressions.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9915-9919
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• 2014

Lamellarin D (LamD) is a marine alkaloid with a pronounced cytotoxicity against a large panel of cancer cells, affecting cell growth and inducing apoptosis. However, the molecular mechanisms of action of this compound are poorly understood. In this study, the anticancer efficacy of LamD was investigated in human leukemia K562 cells. The results showed suppressed cell proliferation and induction of G0/G1-phase arrest,while expression of CDK1, and activity of smad3 and smad5 were reduced, but that of p27, p53 and STGC3 was increased. LamD induced cell apoptosis through activation of caspases-8/-3, inhibition of survivin and Bcl-2, suggesting that this compound may also act through a caspase-independent pathway. Moreover, LamD inhibited the secretion of TGF-${\beta}$, IL-$1{\beta}$, IL-6, IL-8 and other inflammatory cytokines and the transcriptional activity of transcription factor NF-${\kappa}B$ in human leukemia K562 cells.Taken together, our results suggest that LamD-mediated inhibition of leukemia cell proliferation may be related to the induction of apoptosis and the regulation of cell cycle, tumor-related gene expression and cytokine expression, which may provide a new way of thinking for the treatment leukemia.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.65-71
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• 2013

The transient receptor potential melastatin type 7 (TRPM7) channel is a widely expressed non-selective cation channel with fusion to the C-terminal alpha kinase domain and regarded as a key regulator of whole body $Mg^{2+}$ homeostasis in mammals. However, the roles of TRPM7 during osteoclastogenesis in RAW264.7 cells and bone marrow-derived monocyte/macrophage precursor cells (BMMs) are not clear. In the present study, we investigate the roles of TRPM7 in osteoclastogenesis using methods of small interfering RNA (siRNA), RT-PCR, patch-clamp, and calcium imaging. RANKL (receptor activator of NF-${\kappa}B$ ligand) stimulation did not affect the TRPM7 expression and TRPM7-mediated current was activated in HEK293, RAW264.7, and BMM cells by the regulation of $Mg^{2+}$. Knock-down of TRPM7 by siTRPM7 reduced intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) increases by 0 mM $[Mg^{2+}]_e$ in HEK293 cells and inhibited the generation of RANKL-induced $Ca^{2+}$ oscillations in RAW264.7 cells. Finally, knock-down of TRPM7 suppressed RANKL-mediated osteoclastogenesis such as activation and translocation of NFATc1, formation of multinucleated cells, and the bone resorptive activity, sequentially. These results suggest that TRPM7 plays an essential role in the RANKL-induced $[Ca^{2+}]_i$ oscillations that triggers the late stages of osteoclastogenesis.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.6
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• pp.397-403
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• 2011

The proliferation, migration, cytokine release, and contraction of airway smooth muscle cells are key events in the airway remodeling process that occur in lung disease such as asthma, chronic obstruction pulmonary disease, and cancer. These events can be modulated by a number of factors, including cigarette smoke extract (CSE). CSE-induced alterations in the viability, migration, and contractile abilities of normal human airway cells remain unclear. This study investigated the effect of CSE on cell viability, migration, tumor necrosis factor (TNF)-${\alpha}$ secretion, and contraction in normal human bronchial smooth muscle cells (HBSMCs). Treatment of HBSMCs with 10% CSE induced cell death, and the death was accompanied by the generation of reactive oxygen species (ROS). CSE-induced cell death was reduced by N-acetyl-l-cysteine (NAC), an ROS scavenger. In addition, CSE reduced the migration ability of HBSMCs by 75%. The combination of NAC with CSE blocked the CSE-induced reduction of cell migration. However, CSE had no effect on TNF-${\alpha}$ secretion and NF-${\kappa}B$ activation. CSE induced an increase in intracellular $Ca^{2+}$ concentration in 64% of HBSMCs. CSE reduced the contractile ability of HBSMCs, and the ability was enhanced by NAC treatment. These results demonstrate that CSE treatment induces cell death and reduces migration and contraction by increasing ROS generation in normal HBSMCs. These results suggest that CSE may induce airway change through cell death and reduction in migration and contraction of normal HBSMCs.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.315-320
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• 2013

Here, we show that radicicol, a fungal antibiotic, resulted in marked inhibition of inducible nitric oxide synthase (iNOS) transcription by the pancreatic beta cell line MIN6N8a in response to cytokine mixture (CM: TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$). Treatment of MIN6N8a cells with radicicol inhibited CM-stimulated activation of NF-${\kappa}B$/Rel, which plays a critical role in iNOS transcription, in a dose-related manner. Nitrite production in the presence of PD98059, a specific inhibitor of the extracellular signal-regulated protein kinase-1 and 2 (ERK1/2) pathway, was dramatically diminished, suggesting that the ERK1/2 pathway is involved in CM-induced iNOS expression. In contrast, SB203580, a specific inhibitor of p38, had no effect on nitrite generation. Collectively, this series of experiments indicates that radicicol inhibits iNOS gene expression by blocking ERK1/2 signaling. Due to the critical role that NO release plays in mediating destruction of pancreatic beta cells, the inhibitory effects of radicicol on iNOS expression suggest that radicicol may represent a useful anti-diabetic activity.

• Parasites, Hosts and Diseases
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• v.52 no.6
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• pp.605-612
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• 2014

Toxoplasma gondii is an intracellular protozoan parasite that causes a Th1 cellular immunity. Our previous study showed that T. gondii lysate antigen (TLA) treatment in S180 tumor-bearing mice resulted in tumor reduction by suppressing CD31 expression, a marker of angiogenesis. In the present study, to investigate tumor suppressive effect of TLA under the absence of T lymphocytes, athymic nude mice were compared with euthymic mice in the anti-tumorigenic effect triggered by TLA in CT26 tumors. According to the results, intratumorally injected TLA reduced tumor growth and TIMP-1 level, a metastatic marker, in both euthymic and athymic mice. TLA treatment led to a sharp increase in IL-12 expression in serum cytokine profiling of athymic mice, and increased MyD88 signals in macrophages derived from the bone marrow, implying the activation of innate immunity. The selective induction of IL-12 by TLA treatment had an anti-tumorigenic effect.

• Molecules and Cells
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• v.26 no.6
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• pp.583-589
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• 2008

In the present study, we investigated whether rosmarinic acid, which has been suggested to exhibit anti-inflammatory properties, can suppress the expressions of monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-$1{\alpha}$ ($MIP-1{\alpha}$) via the MAPK pathway in LPS-stimulated bone marrow-derived dendritic cells (BMDCs) in the presence of GM-CSF and IL-4 in media. The effects of rosmarinic acid were investigated in BMDCs with respect to the following; cytotoxicity, surface molecule expression, dextran-FITC uptake, cell migration, chemokine gene expression, and the MAPK signaling pathway. Rosmarinic acid was found to significantly inhibit the expressions of CD80, CD86, MHC class I, and MHC class II in LPS-stimulated mature BMDCs, and rosmarinic acid-treated BMDCs were found to be highly efficient with regards to antigen capture via mannose receptor-mediated endocytosis. In addition, rosmarinic acid reduced cell migration by inducing the expression of a specific chemokine receptor on LPS-induced mature BMDCs. Rosmarinic acid also significantly reduced the expressions of MCP-1 and $MIP-1{\alpha}$ induced by LPS in BMDCs and inhibited LPS-induced activation of MAPK and the nuclear translocation of $NF-{\kappa}B$. These findings broaden current perspectives concerning our understanding of the immunopharmacological functions of rosmarinic acid, and have ramifications that concern the development of therapeutic drugs for the treatment of DC-related acute and chronic diseases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.6
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• pp.328-333
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• 2017

Desomodii Herba (DH) has been shown to exhibit pharmacologyical activities, such as increase myocaridal contraction and secretion of hepatic bile. DH is used to reduce pain caused by rheumatoid arthritis(RA) in Korean medicine. However, the DH exact(DHE) effect and mechanism on rheumatoid arthritis are unknown. In this study, we aimed at the inhibitory effect of DHE on rheumatoid arthritis, and investigated the effect in collagen-induced mice arthritis model and TNF-${\alpha}$ induced MMP-1 and MMP-3 expression including the molecular basis in rheumatoid arthritis synovial fibroblasts (RASFs).The effect of DHE on RA was measured by clinical scoring system. In RASFs, expression of MMP-1 and MMP-3 was assessed by Western blotting and real-time PCR. Also, Western blotting used to evaluate the phosphorylation levels of p38, ERK and JNK and activation of NF-${\kappa}B$ and AP-1. Our results showed that DHE reduced collagen-induced arthritis in mice. DHE inhibits TNF-${\alpha}$ induced MMP-1 and MMP-3 expression and mRNA levels in RASFs. The inhibitory effect of DHE was mediated by the inhibition of the AP-1/JNK signaling pathway. Taken together, our results suggest that the DHE may have preventive potential for rheumatoid arthritis.

• Natural Product Sciences
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• v.20 no.2
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• pp.113-118
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• 2014

Ribes fasciculatum which belongs to Saxifragaceae has been widely used as a traditional medicine for the treatment of symptoms associated with lacquer poison. However, pharmacological studies on the R. fasciculatum are extremely limited until now. Thus, in this study, we evaluated the possible anti-inflammatory effects of ethyl acetate fraction of R. fasciculatum (ERF) using IFN-${\gamma}$/LPS-stimulated peritoneal macrophage model. We investigated the change in nitrite level in the absence or presence of ERF after LPS stimulation, and we found that ERF effectively attenuates the NO production in a dose dependent manner without notable toxicity. To determine the mechanism of the inhibitory action of ERF on NO production, we performed iNOS enzyme activity assay and Western blotting. Here we showed that both of iNOS enzyme activities and iNOS expressions were significantly down-regulated by ERF, indicating that these dual activities of ERF are responsible for ERF-mediated NO suppression. In addition, ERF inhibitied the expression of cyclooxygenase-2 (COX-2), an another key enzyme in inflammation through suppression of NF-${\kappa}B$ activation. We also tested anti-inflammatory properties of ERF not only in vitro, but in vivo using trypsin-induced paw edema model in mice. Our results revealed that the increased paw volume in response to trypsin injection was recovered by ERF supplement dose dependently.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.499-505
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• 2012

Chemoprevention represents a strategy designed to protect cells or tissues against various carcinogens and carcinogenic metabolites derived from exogenous or endogenous sources. Recent studies indicate that plant-derived triterpenoids, like oleanolic acid, may exert cytoprotective functions via regulation of the activity of different transcription factors. The chemopreventive effects may be mediated through induction of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor. Activation of Nrf2 by triterpenoids induces the expression of phase 2 detoxifying and antioxidant enzymes such as NAD(P)H quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) - proteins which can protect cells or tissues against various toxic metabolites. On the other hand, inhibition of other transcription factors, like NF-${\kappa}B$ leads to the decrease in the pro-inflammatory gene expression. Moreover, the modulation of microRNAs activity may constitute a new mechanism responsible for valuable effects of triterpenoids. Recently, based on the structure of naturally occurring triterpenoids and with involvement of bioinformatics and computational chemistry, many synthetic analogs with improved biological properties have been obtained. Data from in vitro and in vivo experiments strongly suggest synthetic derivatives as promising candidates in the chemopreventive and chemotherapeutic strategies.