• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.15 no.1
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• pp.44-51
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• 2012

Purpose: Tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) polymorphism has been suggested to play an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) in obese adults, and known to be a mediator of insulin resistance. In this study, we evaluated the role of TNF-${\alpha}$ promoter polymorphisms and insulin resistance in the development of NAFLD in obese children. Methods: A total of 111 obese children (M:F=74:37; mean age, $11.1{\pm}2.0$ yrs) were included. The children were divided into 3 groups: controls (group I, n=61), children with simple steatosis (group II, n=17), and children with non-alcoholic steatohepatitis (group III, n=33). Serum TNF-${\alpha}$ levels, homeostasis model assessment of insulin resistance (HOMA-IR), and TNF-${\alpha}$ -308 and -238 polymorphisms were evaluated. Results: There were no differences in TNF-${\alpha}$ polymorphism at the -308 or the -238 loci between group I and group II + III ($p$=0.134 and $p$=0.133). The medians of HOMA-IR were significantly different between group I and group II + III ($p$=0.001), with significant difference between group II and group III ($p$=0.007). No difference was observed in the HOMA-IR among the genotypes at the -308 locus ($p$=0.061) or the -238 locus ($p$=0.207) in obese children. Conclusion: TNF-${\alpha}$ promoter polymorphisms at the -308 and -238 loci were not significantly associated with the development of NAFLD in children; nevertheless, insulin resistance remains a likely essential factor in the pathogenesis of NAFLD in obese children, especially in the progression to NASH.

• The Journal of Korean Medicine
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• v.26 no.1 s.61
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• pp.85-92
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• 2005

Objective: A number of candidate genes have been in implicated in the pathogenesis of obesity in humans. Tumor necrosis factor-alpha $(TNF-{\alpha})$ is expressed primarily in adipocytes, and elevated levels of this cytokine have been linked to obesity and insulin resistance. Recently, the A allele of a polymorphism at position 308 in the promoter region of $TNF-{\alpha}$ (G-308A) has been shown to increase transcription of the gene in adipocytes. Therefore, we designed this study to test whether obese and non-obese subjects differ in $TNF-{\alpha}$ genotype distribution, and how the genotypes affect anthropometric parameters, including degrees of body mass index (BMI). Methods : The study included 153 obese but otherwise healthy women ($BMI{\geq}kg/m^2$, range 25-54.7, age range 15-40 years) and 82 non-obese healthy women ($BMI, age range 15-40 years). Total fat mass and percent body fat were determined by dual-energy X-ray absorptiometry. Genomic DNA was extracted and used for Ncol restriction fragment length polymorphism (RFLP) based genotyping of $TNF-{\alpha}$. Results: No differences were observed for allelic and genotype frequencies between the obese ($BMI{\geq}25$) and non-obese women. Also, no association of TNF-(l polymorphism was observed with body mass index (BMI) for genotype in obese women. In addition, age, pertent body fat, BMI, and cholesterol levels did not differ by $TNF-{\alpha}$ genotype. However, waist-to­hip ratio (WHR) was significantly lower in subjects with $TNF-{\alpha}$ GA or AA genotype (0.94 0.07 vs. 0.920.03, P<0.005). Conclusion: These results suggest that $TNF-{\alpha}$ promoter polymorphism at position-308 is not a significant factor for BMI, but affects the WHR in obese healthy women from Koreans.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.269-274
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• 2002

A large number of factors such as osteotropic hormones, cytokines, or growth factors are related to the bone remodeling which is characterized by the coupling of osteoclast-mediated bone resorption and osteoblast-mediated bone formation. Recent investigations have indicated that cytokines such as $interleukin-1{\beta}\;(IL-1{\beta})$ and tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ play a potential role in the bone resorption associated with a variety of pathological conditions such as inflammatory osteolytic disease. Collagen is the most abundant protein of the extracellular matrix of bone, and the participation of collagenase in bone resorption has been widely investigated. In this study, effects of $IL-1{\beta}$ and $TNF-{\alpha}$ on the release of collagenase from osteoblastic cells were measured. The gelatinase activity was also measured by gel substrate analysis (zymography) after electrophoresis of conditioned media of osteoblastic cell culture. $IL-1{\beta}$ increased the collagenase activity in ROS17/2.8 and HOS cell culture. $TNF-{\alpha}$ also increased the collagenase activity of osteoblastic cells. When two kinds of cytokines were treated simultaneously in the culture of osteoblastic cells, synergistic increase of collagenase activity was seen in ROS17/2.8 cells. $IL-1{\beta}$ and $TNF-{\alpha}$ significantly increased the collagenase activity after 6 hour treatment in the osteoblastic cell culture, and there was no additional increase according to the culture period. Osteoblastic cells released the gelatinase and molecular weight of this enzyme was measured about 70 KDa as assessed by zymogram. $IL-1{\beta}$ and $TNF-{\alpha}$ showed increase of the gelatinase activity produced by ROS17/2.8 and HOS cells. Taken together, this study suggested that $IL-1{\beta}$ and $TNF-{\alpha}$ can modulate bone metabolism, at least in part, by increased release of collagenase and gelatinase from osteoblasts.

• Reproductive and Developmental Biology
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• v.39 no.3
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• pp.59-67
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• 2015

Galactose-${\alpha}1,3$-galactose (${\alpha}1,3$-Gal) epitope is synthesized at a high concentration on the surface of pig cells by ${\alpha}1,3$-galactosyltransferase gene (GGTA1). The ${\alpha}1,3$-Gal is responsible for hyperacute rejection in pig-to-human xenotransplantation. The generation of transgenic pigs as organ donors for humans is necessary to eliminate the GGTA1 gene that synthesize $Gal{\alpha}$(1,3)Gal. To prevent hyperacute graft rejection in pig-to-human xenotransplantation, previously, we developed ${\alpha}1,3$-galactosyltransferase gene-knock-out somatic cell by homologous recombination. In this study, we established cell lines of ${\alpha}1,3$-GT knock-out expressing hDAF and hHT gene from minipig fibroblasts to apply somatic cell nuclear transfer. The hDAF and hHT mRNA were expressed in the knock-in somatic cells and ${\alpha}1,3$-GT mRNA was suppressed. However, the knock-in somatic cells were increased resistance to human serum-mediated cytolysis.

• Clinical and Experimental Pediatrics
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• v.56 no.4
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• pp.151-158
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• 2013

Purpose: We investigated the mRNA levels of peroxisome proliferator-activated receptor (PPAR)-${\alpha}$, PPAR-${\gamma}$, adipokines, and cytokines in the lung tissue of lean and obese mice with and without ovalbumin (OVA) challenge, and the effect of rosiglitazone, a PPAR-${\gamma}$ agonist. Methods: We developed 6 mice models: OVA-challenged lean mice with and without rosiglitazone; obese mice with and without rosiglitazone; and OVA-challenged obese mice with and without rosiglitazone. We performed real-time polymerase chain reaction for leptin, leptin receptor, adiponectin, vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF)-${\alpha}$, transforming growth factor (TGF)-${\beta}$, PPAR-${\alpha}$ and PPAR-${\gamma}$ from the lung tissue and determined the cell counts and cytokine levels in the bronchoalveolar lavage fluid. Results: Mice with OVA challenge showed airway hyperresponsiveness. The lung mRNA levels of PPAR${\alpha}$ and PPAR-${\gamma}$ increased significantly in obese mice with OVA challenge compared to that in other types of mice and decreased after rosiglitazone administeration. Leptin and leptin receptor expression increased in obese mice with and without OVA challenge and decreased following rosiglitazone treatment. Adiponectin mRNA level increased in lean mice with OVA challenge. Lung VEGF, TNF-${\alpha}$, and TGF-${\beta}$ mRNA levels increased in obese mice with and without OVA challenge compared to that in the control mice. However, rosiglitazone reduced only TGF-${\beta}$ expression in obese mice, and even augmented VEGF expression in all types of mice. Rosiglitazone treatment did not reduce airway responsiveness, but increased neutrophils and macrophages in the bronchoalveolar lavage fluid. Conclusion: PPAR-${\alpha}$ and PPAR-${\gamma}$ expressions were upregulated in the lung tissue of OVA-challenged obese mice however, rosiglitazone treatment did not downregulate airway inflammation in these mice.

• Biomedical Science Letters
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• v.6 no.2
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• pp.83-91
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• 2000

Subconfluent neonatal human epidermal keratinocytes were treated with a concentration 200 ng/$m\ell$ of human recombinant epidermal growth factor (hrEGF), human recombinant insulin-like growth factor-1 (hrIGF-1), and with a combination of hrEGF and hrIGF-1. Cytoplasmic and membrane-associated proteins were extracted and assayed. Proteins were separated by SDS-PAGE, and subjected to the western blot analysis. In the cytoplasmic fraction, the PKC concentration of keratinocyte treated with hrIGF-1 was higher than the control group, but the concentration of control group was the highest than the others in the membrane fraction. In the cytoplasmic fraction, EGF stimulated PKC-$\beta$II, -$\delta$, -$\theta$, and also stimulated PKC-$\alpha$, -$\beta$I, -$\delta$, -$\Im$ and -$\theta$ in the membrane fraction. IGF-1 stimulated PKC-$\beta$I, -$\Im$ and -$\theta$ in the cytoplasmic, PKC-$\alpha$, -$\beta$I, -$\delta$, -$\Im$, - $\varepsilon$ and -$\theta$ in the membrane. In the cells treated with a combination of EGF and IGF-1, PKC-$\alpha$, -$\beta$I, -$\Im$ and -$\theta$ in the cytoplasmic fraction, PKC-$\alpha$, -$\delta$, -$\Im$, -$\varepsilon$ and -$\theta$ in the membrane fraction were stimulated.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.355-359
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• 1997

Leiomyomas, which are the commonest pelvic tumors in women, are originated from myometrial cells. Although the exact initial pathophysiologic event of the leiomyoma is not known, recent evidences suggested that the effects of sex steroid hormones in the process of tumor growth are mediated by local production of growth factors including epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I) and insulin-like growth factor-II (IGF-II). If we look at the effects of other cytokines, it was suggested that basic fibroblast growth factor (bFGF) may stimulate the proliferation of myometrial and leiomyomas cells. And it was reported that interferon-${\alpha}$ inhibit the action of bFGF. Therefore, we examined the effect of bFGF and interferon-${\alpha}$ on the proliferation of leiomyoma and myometrial cells. bFGF stimulated the myometrial and leiomyoma cells significantly at the concentration of 1ng/ml (p<0.05) and 5ng/ml (p<0.05). However, Interferon-${\alpha}$ inhibited the cell proliferation of myometrial and leiomyoma cells significantly at the concentration of 100U/ml (p<0.05) and 1000U/ml (p<0.05). And the stimulated effects of bFGF with the various concentration on the myometrial and leiomyoma cells ware inhibited by interferon-${\alpha}$ with 100U/ml. Therefore, we concluded that bFGF may stimulate the myometrial and leiomyoma cell proliferation and interferon-${\alpha}$ may inhibit the myometrial and leiomyoma cell proliferation through blocking the effect of basic fibroblast growth factor.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.21-30
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• 2003

Background : Mucin synthesis in airways has been reported to be regulated by the epidermal growth factor receptor (EGFR) system. Epidermal growth factor receptor transactivation was identified as a critical element in G-protein-coupled receptors (GPCRs)-induced mitogenic signaling. EGF receptor transactivation by G-protein-coupled receptors requires metalloproteinase cleavage of proHB-EGF. This study was hypothesized that lipopolysaccharide (LPS)-induced mucin production associates with epidermal growth factor receptor transactivation, and MUC5AC production associates with epidermal growth factor receptor transactivation by G-protein-coupled receptors that regulates by metalloproteinase. Method : MUC5AC mucin production was examined in NCI-H292 cells and MUC5AC protein synthesis was assessed using ELISA. For the evaluation of mechanism of LPS-induced MUC5AC production, $TNF{\alpha}$ was measured using ELISA with or without pretreatment of heterotrimeric G-protein inhibitor, mastoparan. MUC5AC protein was measure with pretreatment of polyclonal $TNF{\alpha}$ antibody or mastoparan on LPS-induced MUC5AC production. For the evaluation of relation of G-protein and MUC5AC production, G-protein stimulant, mastopara-7, or matrix metalloproteinase, ADAM10, was added to NCI-H292 cells. MUC5AC protein was measure with pretreatment of polyclonal EGF antibody on mastoparan-7-induced MUC5AC production. Results : LPS alone did not increase significantly MUC5AC production. LPS with $TNF{\alpha}$ induced dose-dependently MUC5AC production in NCI-H292 cells. LPS increased dose-dependently $TNF{\alpha}$ secretion, which was inhibited by mastoparan. LPS with $TNF{\alpha}$-induced MUC5AC production was inhibited by neutralizing polyclonal $TNF{\alpha}$ antibody, mastoparan or AG 1472. Mastoparan-7 or ADAM10 increased dose-dependently MUC5AC production, which was inhibited by polyclonal neutralizing EGF antibody. Conclusion : In LPS-induced MUC5AC synthesis, LPS causes $TNF{\alpha}$ secretion, which induces EGFR expression. EGFR tyrosine kinase phosphorylation result in MUC5AC production. EGF-R transactivation by G-protein-coupled receptors requires matrix metalloproteinase cleavage of proHB-EGF.

• Journal of Veterinary Clinics
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• v.31 no.6
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• pp.469-476
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• 2014

The aims of this study were to explore the effects of conjugated linoleic acid (CLA) on reactive oxygen species (ROS) production in lipopolysaccharide (LPS)-naïve and LPS-stimulated RAW 264.7 macrophages and to examine whether these effects affect the regulation of tumor necrosis factor-alpha (TNF-${\alpha}$) production, and nuclear factor-kappa B (NF-${\kappa}B$) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) activation. Trans-10, cis-12(t10c12)-CLA increased the production of ROS, as well as TNF-${\alpha}$ in LPS-naïve RAW 264.7 cells. The CLA-induced TNF-${\alpha}$ production was suppressed by treatment of diphenyleneiodonium chloride (DPI), a NADPH oxidase inhibitor. In addition, CLA enhanced the activities of NF-${\kappa}B$ and $PPAR{\gamma}$ in LPS-naïve RAW 264.7 cells, and this effect was abolished with DPI treatment. LPS treatment increased ROS production, whereas CLA reduced LPS-induced ROS production. LPS increased both TNF-${\alpha}$ production and NF-${\kappa}B$ activity, whereas t10c12-CLA reduced TNF-${\alpha}$ production and NF-${\kappa}B$ activity in LPS-stimulated RAW 264.7 cells. DPI treatment suppressed LPS-induced ROS production and NF-${\kappa}B$ activity. Moreover, DPI enhanced the inhibitory effects of t10c12-CLA on TNF-${\alpha}$ production and NF-${\kappa}B$ activation in LPS-stimulated RAW 264.7 cells. However, neither t10c12-CLA nor DPI affected $PPAR{\gamma}$ activity in LPS-stimulated RAW 264.7 cells. Taken together, these data indicate that t10c12-CLA induces TNF-${\alpha}$ production by increasing ROS production in LPS-naïve RAW 264.7 cells, which is mediated by the enhancement of NF-${\kappa}B$ activity via $PPAR{\gamma}$ activation. By contrast, t10c12-CLA suppresses TNF-${\alpha}$ production by inhibiting ROS production and NF-${\kappa}B$ activation via a $PPAR{\gamma}$-independent pathway in LPS-stimulated RAW 264.7 cells. These results suggest that t10c12-CLA can modulate TNF-${\alpha}$ production and NF-${\kappa}B$ activation through formation of ROS in RAW 264.7 macrophages.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.294-299
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• 2010

In this study, we tried to investigate whether platycodin D significantly affects MUC5AC mucin production and gene expression induced by epidermal growth factor (EGF), phorbol ester (PMA) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) from human airway epithelial cells. Confluent NCI-H292 cells were pretreated with varying concentrations of platycodin D for 30 min and then stimulated with EGF, PMA and TNF-$\alpha$ for 24h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA. The results were as follows: (1) Platycodin D was found to inhibit the production of MUC5AC mucin protein induced by EGF, PMA, and TNF-$\alpha$, respectively. (2) It also inhibited the expression of MUC5AC mucin gene induced by the same inducers. These results suggest that platycodin D can regulate mucin gene expression and production of mucin protein, by directly acting on human airway epithelial cells.