• Journal of Life Science
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• v.20 no.12
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• pp.1784-1791
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• 2010

In this study, we investigated the effects of ethyl alcohol extracts of Hizikia fusiforme (EHF) on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human gastric adenocarcinoma AGS cells. Inhibitory effects of EHF on cell proliferation, motility, and invasiveness were found to be associated with increased tightness of the TJs, which was demonstrated by an increase in transepithelial electrical resistance. Activities of matrix metalloprotease (MMP)-2 and -9 in AGS cells were dose-dependently inhibited by treatment with EHF, and this was also correlated with a decrease in expression of their mRNA and proteins; however, tissue inhibitor of metalloproteinase (TIMP)-1 and -2 mRNA levels were increased. Additionally, immunoblotting results indicated that EHF repressed the levels of claudin proteins (claudin-1, -3, and -4), major components of TJs that play key roles in control and selectivity of paracellular transport. Furthermore, EHF decreased expression of insulin such as growth factor-1 receptor proteins, while concurrently increasing that of thrombospondin-1 and E-cadherin. In conclusion, these results suggest that EHF treatment may inhibit tumor cell motility and invasion, and therefore act as a dietary source to decrease the risk of cancer metastasis.

• Nutrition Research and Practice
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• v.10 no.5
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• pp.501-506
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• 2016

BACKGROUNG/OBJECTIVES: Corn silk (CS) extract contains large amounts of maysin, which is a major flavonoid in CS. However, studies regarding the effect of CS extract on cholesterol metabolism is limited. Therefore, the purpose of this study was to determine the effect of CS extract on cholesterol metabolism in C57BL/6J mouse fed high-fat diets. MATERIALS/METHODS: Normal-fat group fed 7% fat diet, high-fat (HF) group fed 25% fat diet, and high-fat with corn silk (HFCS) group were orally administered CS extract (100 mg/kg body weight) daily. Serum and hepatic levels of total lipids, triglycerides, and total cholesterol as well as serum free fatty acid, glucose, and insulin levels were determined. The mRNA expression levels of acyl-CoA: cholesterol acyltransferase (ACAT), cholesterol 7-alpha hydroxylase (CYP7A1), farnesoid X receptor (FXR), lecithin cholesterol acyltransferase (LCAT), low-density lipoprotein receptor, 3-hyroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), adiponectin, leptin, and tumor necrosis factor ${\alpha}$ were determined. RESULTS: Oral administration of CS extract with HF improved serum glucose and insulin levels as well as attenuated HF-induced fatty liver. CS extracts significantly elevated mRNA expression levels of adipocytokines and reduced mRNA expression levels of HMG-CoA reductase, ACAT, and FXR. The mRNA expression levels of CYP7A1 and LCAT between the HF group and HFCS group were not statistically different. CONCLUSIONS: CS extract supplementation with a high-fat diet improves levels of adipocytokine secretion and glucose homeostasis. CS extract is also effective in decreasing the regulatory pool of hepatic cholesterol, in line with decreased blood and hepatic levels of cholesterol though modulation of mRNA expression levels of HMG-CoA reductase, ACAT, and FXR.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.400-405
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• 2014

G-protein coupled receptor 119 (GPR119) has emerged as a novel target for the treatment of type 2 diabetes mellitus. GPR119 is involved in glucose-stimulated insulin secretion (GSIS) from the pancreatic b-cells and intestinal cells. In this study, we identified a novel small-molecule GPR119 agonist, HD047703, which raises intracellular cAMP concentrations in pancreatic ${\beta}$-cells and can be expected to potentiate glucose-stimulated insulin secretion from human GPR119 receptor stably expressing cells (CHO cells). We evaluated the acute efficacy of HD047703 by the oral glucose tolerance test (OGTT) in normal C57BL/6J mice. Then, chronic administrations of HD047703 were performed to determine its efficacy in various diabetic rodent models. Single administration of HD047703 caused improved glycemic control during OGTT in a dose-dependent manner in normal mice, and the plasma GLP-1 level was also increased. With respect to chronic efficacy, we observed a decline in blood glucose levels in db/db, ob/ob and DIO mice. These results suggest that HD047703 may be a potentially promising anti-diabetic agent.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5753-5757
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• 2014

Background: The purpose of this study is to determine whether the IGF1R expression has a prognostic role in non-small cell lung cancer. Materials and Methods: Forty-seven patients histopathologically diagnosed with small cell lung cancer upon bronchoscopic biopsy or resection materials were included in the study. IGF1R expression was examined via immunohistochemical methods. In samples, >10% staining were assessed as positive and ${\leq}10%$ as negative. Information about demographic datas and treatments was obtained by retrospective searches of patient files. Results: IGF1R expression was determined as positive in 38 (80.9%) and as negative in 9 (19.1%) patients. There was no significant relation between IGF1R expression and histological sub-type, local invasion, lymph node and metastasis status (p=0.842, p=0.437, 0.064, 0.447, respectively). There was also no correlation with IGF1R expression and survival (p=0.141). Conclusions: There are conflicting results between IGF1R and its prognostic effects in the various studies. It has been claimed in some studies it is not related to prognosis as in our study, and in some studies it has been claimed that it is a good prognostic factor whereas in some studies it has been claimed as being a factor for worse prognosis. We think that IGF1R expression in non-small cell lung carcinoma patients deserves further analysis, because of its potential prognostic and predictive roles.

• Toxicological Research
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• v.29 no.1
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• pp.7-14
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• 2013

Betaine supplementation has been shown to alleviate altered glucose and lipid metabolism in mice fed a high-fat diet or a high-sucrose diet. We investigated the beneficial effects of betaine in diabetic db/db mice. Alleviation of endoplasmic reticulum (ER) and oxidative stress was also examined in the livers and brains of db/db mice fed a betaine-supplemented diet. Male C57BL/KsJ-db/db mice were fed with or without 1% betaine for 5 wk (referred to as the db/db-betaine group and the db/db group, respectively). Lean non-diabetic db/+ mice were used as the control group. Betaine supplementation significantly alleviated hyperinsulinemia in db/db mice. Betaine reduced hepatic expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha, a major transcription factor involved in gluconeogenesis. Lower serum triglyceride concentrations were also observed in the db/db-betaine group compared to the db/db group. Betaine supplementation induced hepatic peroxisome proliferator-activated receptor alpha and carnitine palmitoyltransferase 1a mRNA levels, and reduced acetyl-CoA carboxylase activity. Mice fed a betaine-supplemented diet had increased total glutathione concentrations and catalase activity, and reduced lipid peroxidation levels in the liver. Furthermore, betaine also reduced ER stress in liver and brain. c-Jun N-terminal kinase activity and tau hyperphosphorylation levels were lower in db/db mice fed a betaine-supplemented diet, compared to db/db mice. Our findings suggest that betaine improves hyperlipidemia and tau hyperphosphorylation in db/db mice with insulin resistance by alleviating ER and oxidative stress.

• Nutrition Research and Practice
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• v.7 no.6
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• pp.439-445
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• 2013

It has been shown that dysregulation of IGF-1 signaling is associated with tumor incidence and progression, whereas blockade of the signaling can effectively inhibit carcinogenesis. Although several mechanisms of anticancer activity of quercetin were proposed, molecular targets of quercetin have not been identified yet. Hence, we assessed the effect of quercetin on IGF-1 signaling inhibition in BK5.IGF-1 transgenic (Tg) mice, which over-expresses IGF-1 in the skin epidermis. A quercetin diet (0.02% wt/wt) for 20 weeks remarkably delayed the incidence of skin tumor by 2 weeks and reduced tumor multiplicity by 35% in a 7,12-dimethylbenz(a)anthracene (DMBA)-tetradecanoyl phorbol-13-acetate (TPA) two stage mouse skin carcinogenesis protocol. Moreover, skin hyperplasia in Tg mice was significantly inhibited by a quercetin supplementation. Further analysis of the MT1/2 skin papilloma cell line showed that a quercetin treatment dose dependently suppressed IGF-1 induced phosphorylation of the IGF-1 receptor (IGF-1R), insulin receptor substrate (IRS)-1, Akt and S6K; however, had no effect on the phosphorylation of PTEN. Additionally, the quercetin treatment inhibited IGF-1 stimulated cell proliferation in a dose dependent manner. Taken together, these data suggest that quercetin has a potent anticancer activity through the inhibition of IGF-1 signaling.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.2
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• pp.66-77
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• 2012

Objectives: This study was designed to investigate the effects of PR on ovarian tissue in PCOS rats through measurement of morphological and histo-pathological observations, ovarian size. In addition, effects on expression levels of Insulin like Growth Factor Receptor(IGFR) were also investigated to elucidate related mechanisms. Methods: PCOS was induced by single intermuscular injection with ${\beta}$-Estradiol 17-Valerate(EV) in female rats. Normal group(NOR, n=8) were injected with sesame oil and administrated hard food for five weeks. Control group(CTL, n=8) were injected with EV and administrated hard food for five weeks. CR group(n=8) were injected with EV and administrated hard food mixed CR for five weeks. Then, we measured weights of body and ovary, uptakes of food and water. And we observed morphological and histo-pathological changes of ovary, levels of IGFR. Results: In this experiments, single injection of Estradiol Valerate(EV) induced suppression of weight gain, formation of cysts, increase of IGFR expression. Oral administration of PR prevent decrease of ovarian size significantly. Further more, formation of cystic follicles induced by EV injection is suppressed by PR treatment. Conclusions: These results suggest PR can be used for patients with PCOS to prevent formation of cystic follicles and malfunction of ovary.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.563-570
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• 2004

The insulin-like growth factor(IGF) system, consisting of IGFs-I and -II ligands and their receptors and six IGF-binding proteins(IGFBPs), plays an important role in survival, proliferation and differentiation of a variety of cell types. Lithium is a known modulator of survival and proliferation of many cell types in vitro. The present study was undertaken to investigate the relationship between LiCI-induced changes in cell survival and growth and the expression of the IGF system components in C6 rat glioma cell line which, besides IGF-I and its receptor, is known to express IGFBP-3 as its major IGF carrier. When C6 cells were cultured for 24h in the absence or presence of 2mM or 5mM LiCl in a 10% serwn-containing medium, the viability and the number of cells were not affected by added lithium. In 72-h culture, however, C6 cells clearly exhibited a dose-dependent response to added LiCl. The cells cultured for 72h in the presence of 0, 2mM and 5mM LiCl exhibited a typical mitotic, a growth-arrested and an apoptotic appearances, respectively. Moreover, the apoptotic cells were accompanied by reduced expression of IGF-I, IGF-I receptor and IGFBP-3 as examined by semi-quantitative reverse transcription-polymerase chain reaction. Interestingly, blockade of IGFBP-3 mRNA translation by addition of 101${\mu}M$ IGFBP-3 anti-sense oligodeoxyribonucleotide in serum-free, 24-h culture resulted in a decrease in the number of cells as well as relative abundance of the target mRNA. In summary, results suggest that the cytotoxic effect of lithium in C6 cell is likely to be mediated, in part, by suppression by this agent of the expression of the IGF system components. In this regard, IGFBP-3 may play at least a 'permissive' role in normal proliferation of this cell.

• Journal of Ginseng Research
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• v.43 no.4
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• pp.527-538
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• 2019

Background: Ginsenoside Rg1 was shown to exert ligand-independent activation of estrogen receptor (ER) via mitogen-activated protein kinase-mediated pathway. Our study aimed to delineate the mechanisms by which Rg1 activates the rapid ER signaling pathways. Methods: ER-positive human breast cancer MCF-7 cells and ER-negative human embryonic kidney HEK293 cells were treated with Rg1 ($10^{-12}M$, $10^{-8}M$), $17{\beta}$-estradiol ($10^{-8}M$), or vehicle. Immunoprecipitation was conducted to investigate the interactions between signaling protein and ER in MCF-7 cells. To determine the roles of these signaling proteins in the actions of Rg1, small interfering RNA or their inhibitors were applied. Results: Rg1 rapidly induced $ER{\alpha}$ translocation to plasma membrane via caveolin-1 and the formation of signaling complex involving linker protein (Shc), insulin-like growth factor-I receptor, modulator of nongenomic activity of ER (MNAR), $ER{\alpha}$, and cellular nonreceptor tyrosine kinase (c-Src) in MCF-7 cells. The induction of extracellular signal-regulated protein kinase and mitogen-activated protein kinase kinase (MEK) phosphorylation in MCF-7 cells by Rg1 was suppressed by cotreatment with small interfering RNA against these signaling proteins. The stimulatory effects of Rg1 on MEK phosphorylation in these cells were suppressed by both PP2 (Src kinase inhibitor) and AG1478 [epidermal growth factor receptor (EGFR) inhibitor]. In addition, Rg1-induced estrogenic activities, EGFR and MEK phosphorylation in MCF-7 cells were abolished by cotreatment with G15 (G protein-coupled estrogen receptor-1 antagonist). The increase in intracellular cyclic AMP accumulation, but not Ca mobilization, in MCF-7 cells by Rg1 could be abolished by G15. Conclusion: Ginsenoside Rg1 exerted estrogenic actions by rapidly inducing the formation of ER containing signalosome in MCF-7 cells. Additionally, Rg1 could activate EGFR and c-Src ER-independently and exert estrogenic effects via rapid activation of membrane-associated ER and G protein-coupled estrogen receptor.

• Journal of Life Science
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• v.21 no.10
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• pp.1385-1392
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• 2011

It is well known that both insulin-like growth factor-I and suppressor of cytokine signaling-3 (SOCS-3) are known to modulate various aspects of physiology in skeletal muscle cells. Furthermore, although SOCS-3 expression is related to insulin resistance in non-skeletal muscle cells and is known to interact with insulin-like growth factor-I receptor, the effect of IGF-I on SOCS-3 gene expression in skeletal muscle cells is presently unknown. C2C12 myotubes were treated with different concentrations (0-200 ng/ml) of IGF-I or for various periods of time (3-72 hr). Immunofluorescent staining image revealed that IGF-I induced SOCS-3 protein expression in a dose-dependent manner. Western blot data also showed that SOCS-3 proteins were induced by IGF-I (200 ng/ml) in C2C12 myotubes in a time-dependent manner. The level of SOCS-3 mRNA was also significantly increased after 3hr of IGF-I (10-100 ng/ml) treatment. However, the levels of SOCS-3 mRNA were significantly decreased after 24 and 48 hr of IGF-I (10-100 ng/ml) treatment compared to the control. In conclusion, SOCS-3 protein is induced by IGF-I treatment in C2C12 skeletal muscle cells and this induction is regulated pretranslationally. The modulating effect of IGF-I on SOCS-3 expression may be an important regulator of gene expression in skeletal muscle cells.