• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1316-1321
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• 2012

Adipokines, adipocyte-derived protein, have important roles in various kinds of physiology including energy homeostasis. Chemerin, one of adipocyte-derived adipokines, is highly expressed in differentiated adipocytes and is known to induce macrophage chemotaxis and glucose intolerance. The objective of the present study was to investigate the changes of chemerin and the chemokine-like-receptor 1 (CMKLR1) gene expression levels during differentiation of the bovine adipocyte and in differentiated adipocytes treated with tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), adiponectin, leptin, and chemerin (peptide analog). The expression levels of the chemerin gene increased at d 6 and 12 of the differentiation period accompanied by increased cytoplasm lipid droplets. From d 6 onward, peroxisome proliferator-activated receptor-${\gamma}2$ (PPAR-${\gamma}2$) gene expression levels were significantly higher than that of d 0 and 3. In contrast, CMKLR1 expression levels decreased at the end of the differentiation period. In fully differentiated adipocytes (i.e. at d 12), the treatment of TNF-${\alpha}$ and adiponectin upregulated both chemerin and CMKLR1 gene expression levels, although leptin did not show such effects. Moreover, chemerin analog treatment was shown to upregulate chemerin gene expression levels regardless of doses. These results suggest that the expression of chemerin in bovine adipocyte might be regulated by chemerin itself and other adipokines, which indicates its possible role in modulating the adipokine secretions in adipose tissues.

• Molecules and Cells
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• v.41 no.8
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• pp.762-770
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• 2018

Adiponectin, a hormone produced by adipose tissue, is very abundant in plasma, and its anti- and pro-inflammatory effects are reported. However, the mechanisms of these pro- and anti-inflammatory effects are not fully defined. Herein, we evaluated the dual inflammatory response mechanism of adiponectin in macrophages. Short-term globular adiponectin (gAd) treatment induced $I{\kappa}B{\alpha}$ degradation, $NF-{\kappa}B$ nuclear translocation, and $TNF-{\alpha}$ production in RAW 264.7 cells. Polymyxin B pretreatment did not block gAd-induced $I{\kappa}B{\alpha}$ degradation, and heated gAd was unable to degrade $I{\kappa}B{\alpha}$, suggesting that the effects of gAd were not due to endotoxin contamination. gAd activated IKK and Akt, and inhibition of either IKK or Akt by dominant-negative $IKK{\beta}$ ($DN-IKK{\beta}$) or DN-Akt overexpression blocked gAd-induced $I{\kappa}B{\alpha}$ degradation, suggesting that short-term incubation with gAd mediates inflammatory responses by activating the $I{\kappa}B/NF-{\kappa}B$ and PI3K/Akt pathways. Contrastingly, long-term stimulation with gAd induced, upon subsequent stimulation, tolerance to gAd, lipopolysaccharide, and CpG-oligodeoxynucleotide, which is associated with gAd-induced downregulation of IL-receptor-associated kinase-1 (IRAK-1) due to IRAK-1 transcriptional repression. Conclusively, our findings demonstrate that the pro- and anti-inflammatory responses to gAd in innate immune cells are time-dependent, and mediated by the activation of the $I{\kappa}B/NF-{\kappa}B$ pathway, and IRAK-1 downregulation, respectively.

• Korean Journal of Community Nutrition
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• v.16 no.6
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• pp.762-770
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• 2011

Osteoprotegerin (OPG) plays a core role in bone reformation by antagonizing the effect of receptor activator of nuclear factor ${\kappa}$-B ligand (RANKL), and mediates vascular calcification in cardiovascular disease patients. Thus, we aimed to examine the relationship between serum OPG levels and cardiovascular factors and inflammatory markers in metabolic syndrome patients (MS). This cross-sectional study included 96 men who visited the diet clinic between May and July 2011. Patients were classified into 2 groups based on NCEP-ATP guidelines: normal and with MS (n = 50 and 46, respectively). Physical measurements, biochemical assay were measured. Serum OPG and IL-6, diponectin and hs-CRP were assessed. MS were aged $50.02{\pm}10.85$ years, and normal patients $52.07{\pm}9.56$ years, with no significant differences. Significant differences were not observed in BMI between the 2 groups. Moreover, significant differences were not observed in serum OPG, however, the serum OPG level ($4.41{\pm}1.86pmol/L$) differed significantly between an overweight MS (BMI > 25) and normal patients. OPG was correlated to age (r = 0.410, p = 0.000), HDL-cholesterol (r = 0.209, p = 0.015), and log adiponectin (r = 0.175, p = 0.042). Multiple regression analyses using the enter method showed that age (${\beta}$ = 0.412, p = 0.000) and BMI (${\beta}$ = 0.265, p = 0.000) considerably affected OPG. In conclusion, out study showed that serum OPG levels are correlated with cardiovascular risk factors, such as BMI, HDL-cholesterol and adiponectin in MS and adiponectin, suggesting that serum OPG has potential as a cardiovascular disease indicator and predictor.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.637-643
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• 2013

We have demonstrated that 1-deoxynojirimycin (DNJ) isolated from Bacillus subtilis MORI could enhance the levels of adiponectin and its receptors in differentiated 3T3-L1 adipocytes, which has been shown to be effective in lowering blood glucose levels and enhancing insulin sensitivity. DNJ was not toxic to differentiated 3T3-L1 adipocytes for up to a concentration of $5{\mu}M$. In terms of expression levels of adiponectin and its receptors (AdipoR1 and AdipoR2), DNJ in concentrations as low as $0.5{\mu}M$ elevated both mRNA and protein levels of adiponectin and transcript levels of AdipoR1 and AdipoR2. In addition, DNJ increased phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK) in a statistically significant manner. Finally, treatment with DNJ resulted in increased mRNA expression of glucose transporter 4 (GLUT4), which encodes for a glucose transporter, along with a significant increase in glucose uptake into the adipocytes based on results of a 2-deoxy-D-[$^3H$] glucose uptake assay. Our findings indicate that DNJ may greatly facilitate glucose uptake into adipose tissues by increasing the action of adiponectin via its up-regulated expression as well as its receptor genes. In addition, the glucose-lowering effects of DNJ may be achieved by an increased abundance of GLUT4 protein in the plasma membrane, as a consequence of the increased transcript levels of the GLUT4 gene and the activation of AMPK.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.129-135
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• 2012

GPAR{elidium (G.) amansii is a red alga widely distributed in the shallow waters around East Asian countries. We investigated the effect of G. amansii on lipid accumulation and ROS (Reactive Oxygen Species) production in 3T3-L1 cells. G. amansii extracts dose-dependently inhibited lipid formation and ROS generation in cultured cells. Our results showed that anti-adipogenic effect of G. amansii was due to the reduction in mRNA expressions of PPAR${\gamma}$(peroxisome proliferator-activated receptor-${\gamma}$) and aP2 (adipocyte protein 2). G. amansii extracts significantly decreased mRNA levels of a ROS-generator, NOX4 (nicotinamide adenine dinucleotide phosphate hydrogen oxidase 4), and increased the protein levels of antioxidant enzymes including SOD1/2 (superoxide dismutases), Gpx (glutathione peroxidase), and GR (glutathione reductase), which can lead to the reduction of ROS in the cell. In addition, the G. amansii extract enhanced mRNA levels of adiponectin, one of the adipokines secreted from adipocytes, and GLUT4, glucose uptake protein. Taken together, our study shows that G. amansii extract inhibited lipid accumulation and ROS production by controlling adipogenic signals and ROS regulating genes.

• Development and Reproduction
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• v.24 no.4
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• pp.287-296
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• 2020

The absence of functional estrogen receptor α (Esr1) results in an overgrowth of the epididymal fat, as observed in estrogen receptor α knockout (ERαKO) mouse. The present research was aimed to evaluate expression of various molecules associated with adipocyte differentiation and maturation in the epididymal fat of ERαKO mouse at several postnatal ages by using quantitative real-time polymerase chain reaction. The highest transcript levels of all molecules were detected at 12 months of postnatal age, except leptin which the mRNA level was increased at 5 months of age and was unchanged until 12 months of age. The expression levels of CCAAT enhancer binding protein (Cebp) alpha, androgen receptor, and lipoprotein lipase were decreased at 5 months of age but increased at about 8 months of age. The mRNA levels of Cebp gamma and sterol regulatory element binding transcription factor 1 remained steady until 8 months of age. Continuous increases of transcript levels during postnatal period were found in Cebp beta, estrogen receptor (ER) beta, fatty acid binding protein 4, and delta like non-canonical Notch ligand 1. The increases of peroxisome proliferator-activated receptor gamma and adiponectin mRNA levels were detected as early as 8 months of age. The levels of fatty acid synthase and resistin transcript at 5 and 8 months of age were lower than that at 2 months of age. These findings show the aberrant expression patterns of genes related to adipocyte differentiation and maturation in the postnatal epididymal fat pad by the disruption of ER alpha function.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3963-3969
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• 2016

Purpose:To assess IGFBP-6 expression in relation with the presence of the metabolic syndrome, adiponectin receptors (AdipoR1 and AdipoR2) and IGF-IR levels in colorectal adenocarcinoma cases. Materials and Methods: IGFBP-6 mRNA and protein levels were analyzed using real-time quantitative PCR and Western blotting in 46 patients. ELISA and flow cytometry were used for evaluation of AdipoR1, AdipoR2 and IGF-IR. Results: The results showed that IGFBP-6 mRNA expression and the IGFBP-6 content were higher in tumor tissue samples of colorectal cancer patients with tahtn without metabolic syndrome. In addition, the IGFBP-6 mRNA expression was associated with tumor invasion (tumor size) and the IGFBP-6 protein level was associated with nodal status. Positive correlations and positive nonlinear relations were found between the IGFBP-6 level and the AdipoR1 and AdipoR2 contents in colorectal cancer patients. Conclusions: The IGFBP-6 mRNA level and protein level were found to be associated with presence of metabolic syndrome. Positive correlations indicated probable cross-talk between the IGF-IR-mediated and adiponectin-mediated signaling pathways in colorectal carcinomas. IGFBP-6 may be considered as a potential biomarker associated with lymphogenous metastasis and the metabolic syndrome in colorectal cancer.

• 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.

• Nutrition Research and Practice
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• v.8 no.2
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• pp.158-164
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• 2014

BACKGROUD/OBEJECTIVES: This study aims to find out the effects of peanut sprout extracts on weight controls and protein expressions of transcription factors related to adipocyte differentiation and adipocytokine in rats under high-fat diets. MATERIALS/METHODS: Four week-old Sparague-Dawley (SD) were assigned to 4 groups; normal-fat (NF) diets (7% fat diet), high-fat (HF) diets (20% fat diet), high fat diets with low peanut sprout extract (HF + PSEL) diet (20% fat and 0.025% peanut sprout extract), and high fat diets with high peanut sprout extract (HF + PSEH) diet (20% fat and 0.05% peanut sprout extract). Body weight changes, lipid profiles in adipose tissue, and the mRNA protein expressions, such as peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$), CCAAT element binding protein ${\alpha}$ (C/EBP ${\alpha}$), leptin, and adiponectin, were determined. RESULTS: After 9 weeks of feeding, the HF + PSEH group had significantly less weight gains than the HF group (P < 0.05). However, the total dietary intakes or food efficiency ratios among groups were not significantly different. The weight of epididymal fat in HF + PSEH group, $3.61{\pm}0.5g$, or HF + PSEL group, $3.80{\pm}0.7g$, was significantly lower than the HF group, $4.39{\pm}0.4g$, (P < 0.05). Total lipids and total cholesterol in adipose tissue were significantly decreased in HF + PSEH group compared to those in the HF group, respectively (P < 0.05). PSEH supplementation caused AST and ALT levels to decrease when it compared to HF group, but it was not statistically significant. The protein expression of $PPAR{\gamma}$ in HF + PSEH group was significantly lower than the HF group (P < 0.05). Comparing with the HF group, the protein expression of adiponectin in HF + PSEH group was significantly increased (P < 0.05). The protein expressions of C/EBP ${\alpha}$ and leptin in HF + PSEH group were lower than the HF group, but it was not statistical significant. CONCLUSIONS: In conclusion, peanut sprout extract has anti-obesity effect by lowering the expressions of $PPAR{\gamma}$ which regulates the expression of adiponectin.

• Journal of Periodontal and Implant Science
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• v.41 no.3
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• pp.149-156
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• 2011

Purpose: Globular adiponectin (gAd) is a type of adipocytokine, which is mainly produced by adipose tissue. It has been reported that gAd acts as a pro- as well as an anti-inflammatory factor. Interleukin (IL)-6 and IL-8 are pro-inflammatory cytokines. To investigate the role of gAd on periodontal tissues, the expression of adiponectin receptor 1 (AdipoR1) and the effect of gAd on the expression of IL-6 and IL-8 were investigated in periodontal ligament (PDL) and gingival fibroblasts. Methods: PDL and gingival fibroblasts were cultured from human periodontal tissues. gAd derived from Escherichia coli and murine myeloma cells were used. The expression of AdipoR1 was estimated by reverse transcription-polymerase chain reaction and western blot The expression of cytokines was measured by enzyme-linked immunosorbent assay. Results: PDL and gingival fibroblasts expressed both mRNA and protein of AdipoR1. gAd derived from E. coli increased the production of IL-6 and IL-8, but polymyxin B, an inhibitor of lipopolysaccharide (LPS), inhibited IL-6 and IL-8 production induced by gAd in both types of cells. gAd derived from murine myeloma cells did not induce IL-6 and IL-8 production in those cells. gAd derived from E. coli contained higher levels of LPS than gAd derived from murine myeloma cells. LPS increased production of IL-6 and IL-8 in PDL and gingival fibroblasts, but pretreatment of cells with gAd derived from murine myeloma cells did not inhibit LPS-induced IL-6 and IL-8 expression. Conclusions: Our results suggest that PDL and gingival fibroblasts express AdipoR1 and that gAd does not act as a modulator of IL-6 and IL-8 expression in PDL and gingival fibroblasts.