• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1760-1764
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• 2002

In order to elucidate the physiological function of circulating IGF-I on muscle protein synthesis in the chicken under malnutritional conditions, we administrated recombinant chicken IGF-I using a osmotic mini pump to fasted young chickens and measured the rate of muscle protein synthesis and plasma metabolite. The pumps delivered IGF-I at the rate of $22{\mu}g/d\{300{\mu}g{\cdot}(kg\;body\;weight{\cdot}d)^{-1}\}$. Fractional rate of protein synthesis in the muscle was measured using a large dose injection of L-[$2,6-^3H$]phenylalanine. Constant infusion of chicken IGF-I did not affect plasma glucose level. Significant interaction between dietary treatment and IGF-I infusion was observed in plasma NEFA and total cholesterol concentrations. When chicks were fasted, IGF-I infusion decreased plasma NEFA and total cholesterol concentrations. On the other hand, IGF-I administration did not affect plasma levels of both metabolites. Fasting reduced plasma triglyceride concentration significantly. IGF-I infusion also decreased the level of plasma triglyceride. Plasma IGF-I concentration of young chickens was halved by fasting for 1 d. IGF-I infusion using an osmotic minipump for 1 d increased plasma IGF-I concentration in fasted chicks to the level of fed chicks. Fasting decreased body weight and the loss of body weight was significantly ameliorated by IGF-I infusion. There was a significant interaction between dietary treatment and IGF-I infusion in the fractional rate of breast muscle protein synthesis. There was no effect of IGF-I infusion on muscle protein synthesis in fed chicks. Muscle protein synthesis reduced by fasting was ameliorated by IGF-I infusion, but did not reach to the level of fed control. Muscle weight of fasted chicks infused with IGF-I was similar to fasted birds without IGF-I infusion, which suggests that muscle protein degradation would be increased by IGF-I infusion as well as protein synthesis in fasted chicks.

• BMB Reports
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• v.34 no.4
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• pp.385-389
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• 2001

Insulin-like growth factor binding protein-1 (IGFBP-1) appears to be an important modular of the insulin growth factor (IGF) bioactivity in metabolic disease and chronic hypoxia. Treatment of desferrioxamine (Dfo), cobalt, or nickel in HepG2 cells stimulated the expression of IGFBP1 mRNA as hypoxia. However, the presence of ferric ammonium citrate (FAC) in the 1% $O_2$ decreased the upregulation of the IGFBP-1 mRNA expression. In addition, actinomycin D and cycloheximide abolished the increase in the expression of IGFBP-1 mRNA that was induced by Dfo and transition metals (cobalt and nickel). To obtain further information about the putative oxygen sensor, we postulate that putative heme proteins, responsible for the oxygen-sensing process in HepG2 cells, should be sensitive to hypoada. The mechanism of these upregulations of the IGFBP-1 mRNA expression by Dfo and transition metals was investigated by treatment with 2 mM of 4,6-dioxoheptanoic acid (DHA), an inhibitor of heme biosynthesis. The results showed that 1% $O_2$-, Dfo-, cobalt-, or nickel induced IGFBP-1 mRNA expressions in HepG2 cells were all markedly inhibited when the heme synthesis was blocked by DHA. We suggest that the IGFBP-1 mRNA expression in the HepG2 cell is regulated by 1% $O_2$, Dfo, cobalt, or nickel, implicating the involvement of the putative heme-containing oxygensensing molecule.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.10
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• pp.1508-1514
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• 2016

A series of antagonists specifically targeting growth hormone receptors (GHR) in different species, such as humans, rats, bovines, and mice, have been designed; however, there are currently no antagonists that target the porcine growth hormone (GH). Therefore, in this study, we developed and characterized a porcine GHR (pGHR) antibody antagonist (denoted by AN98) via the hybridoma technique. The results from enzyme-linked immunosorbent assay, fluorescence activated cell sorter, indirect immunoinfluscent assay, and competitive receptor binding analysis showed that AN98 could specifically recognize pGHR, and further experiments indicated that AN98 could effectively inhibit pGH-induced signalling in CHO-pGHR cells and porcine hepatocytes. In addition, AN98 also inhibited GH-induced insulin-like growth factor-1 (IGF-1) secretion in porcine hepatocytes. In summary, these findings indicated that AN98, as a pGHR-specific antagonist, has potential applications in pGH-pGHR-related research on domestic pigs.

• Journal of Periodontal and Implant Science
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• v.30 no.2
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• pp.389-405
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• 2000

The purpose of this study is to evaluate the effect of IGF-I for DNA synthetic activity and the mRNA expression of bone matrix protein, type I collagen and osteopontin in prolifetation and differentiation of MC3T3-E1 cells. To evaluate DNA synthetic activity, cells were seeded at $2{\times}10^4cells/ml$ in 24 well plates and to evaluate mRNA of type I collagen and osteopontin cells were seeded at $5{\times}10^5cells/ml$ in 100mm culture dishes. These cells were cultured in alpha-minimum essential medium(${\alpha}-MEM$) containing 10% fetal bovine serum at $37^{\circ}C$, 5% $CO_2$ incubator. For DNA synthetic activity test 1, 10, 100ng/ml IGF-I were added to the cells which had been cultured for 3 days before 24 hours. For type I collagen mRNA expression 1, 10ng/ml IGF-I were added to the cells which had been cultured for 5, 10 days and for osteopontin mRNA expression 0.1, 1, 10ng/ml IGF-I were added to the cells which had been cultured for 5, 15, 20 days. Cell proliferaton was measured by the incorporation of [$^3H$]-thymidine into DNA and expression for type I collagen and osteopontin were measured by northern blot analysis. The results were as follows : DNA synthetic activity were generally higher in experimental group than control group. Expressions of type I collagen mRNA were higher at 5 day group and much lower at 10 day group in the control groups. In the experimental groups, mRNA expressions were slightly increased when 1 ng/ml IGF-I were added to 5 day group and decreased in all experimental 10 day groups. Expressions of osteopontin mRNA were higher at 20 day groups and lower at 15 day groups than the control groups. In the experimental groups, mRNA expressions were incereased when 0.1, 1 ng/ml IGF-I were added to 5 day group and in all the 15 day groups, but decreased when 0.1, 1, 10 ng/ml IGF-I were added to 20 day groups. IGF-I stimulated DNA synthetic activity of MC3T3-E1 cells during proliferation stage significantly, did not greatly changed effects on type I collagen mRNA expression and stimulated osteopontin mRNA expression at 15 day especially. In conclusion, we suggests that IGF-I have a tendency of stimulation effect of DNA synthetic activity but do not stimulate type I collagen mRNA in proliferation stage of MC3T3-E1 cell cultures, and stimulate osteopontin mRNA in differentiation stage of MC3T3-E1 cell cultures.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.783-794
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• 1996

It has been suggested that ion transport systems are intimately involved in mediating the effects of growth regulatory factors on the growth of a number of different types of animal cells in vivo. The functional importance of the apical membrane $Na^+/H^+$ antiporter in the renal proximal tubule is evidenced by estimates that this transporter mediates the reabsorption of approximately one third of the filtered load of sodium and the bulk of the secretion of hydrogen ions. This study was designed to investigate the pathway utilized by IGF-I in regulating sodium transport in primary cultured renal proximal tubule cells. Results were as follows : 1. $Na^+$ was observed to accumulate in the primary cells as a function of time. Raising the concentration of extracellular NaCl induced an decrease in $Na^+$ uptake compared with control cells in a dose dependent manner. The rate of $Na^+$ uptake into the primary cells was about two times higher in the absence of NaCl($40.11{\pm}1.76pmole\;Na^+/mg\;protein/min$) than in the presence of 140mM NaCl($17.82{\pm}0.94pmole\;Na^+/mg\;protein/min$) at the 30 minute uptake. 2. $Na^+$ uptake was inhibited by IAA($1{\times}10^{-4}M$) or valinomycin($5{\times}10^{-6}M$) treatment($50.51{\pm}4.04$ and $57.65{\pm}2.27$ of that of control, respectively). $Na^+$ uptake by the primary proximal tubule cells was significantly increased by ouabain($5{\times}10^{-5}M$) treatment($140.23{\pm}3.37%$ of that of control). When actinomycin D($1{\times}10^{-7}M$) or cycloheximide($4{\times}10^{-5}M$) was applied, $Na^+$ uptake was decreased to $90.21{\pm}2.39%$ or $89.64{\pm}3.69%$ of control in IGF-I($1{\times}10^{-5}M$) treated cells, respectively. 3. Extracellular cAMP decreased $Na^+$ uptake in a dose-dependent manner($10^{-8}-10^{-4}M$). IBMX($5{\times}10^{-5}M$) also inhibited $Na^+$ uptake. Treatment of cells with pertussis toxin(50pg/ml) or cholera toxin($1{\mu}g/ml$) inhibited $Na^+$ uptake. Extracellular PMA decreased $Na^+$ uptake in a dose-dependent manner(1-100ng/ml). 100 ng/ml PMA concentration significantly inhibited $Na^+$ uptake in IGF-I treated cells. However, staurosporine($1{\times}10^{-7}M$) had no effect on $Na^+$ uptake. When PMA and staurosporine were added together, the inhibition of $Na^+$ uptake was not observed. In conclusion, sodium uptake in primary cultured rabbit renal proximal tubule cells was dependent on membrane potentials and intracellular energy levels. IGF-I stimulates sodium uptake through mechanisms that involve some degree of de novo protein and/or RNA synthesis, and cAMP and/or PKC pathway mediating the action mechanisms of IGF-I.

• Korean Journal of Poultry Science
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• v.32 no.2
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• pp.135-141
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• 2005

Changes in serum estradiol, insulin-like growth factor-1, leuteinizing and testosterone levels, and leuteinizing hormone-stimulated testosterone production per testis in vitro from hatching to adulthood were studied in Korean native chickens of 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 21, 24, 28, 32, 44, 52 and 64 weeks (n=13 chickens per group) of age. The changes in the profiles of the levels in the incubation medium of luteinizing hormone-stimulated (100 ng/mL) testosterone secretion per testis in vitro, and the serum LH, testosterone, estradiol, and insulin-like growth factor-I were determined by radioimmunoassay. Serum estradiol levels were not significantly different at week 4 compared to that of 8, 12, 16, 21, 32, :md 44. Significant decreases were observed at weeks 52 and 64. Serum leuteinizing hormone concentrations were not significantly different from 1 week to 12 weeks, increased gradually up to 32 weeks of age, and declined significantly thereafter; the highest value was at 32 weeks, and the lowest value was detected at 2 weeks of age. Serum insulin-like growth factor-I concentrations increased significantly from 1 week to 16 weeks, remained low and unchanged with advancing age. Serum testosterone concentrations were not significantly different at week 1 compared weeks 2, 4, 6, and 8. Significant increases were observed from 10 weeks to 32 weeks of age. Values at weeks 24, 28 and 32 and at weeks 32, 44, 52, and 64 were not significantly different. The highest value was at weeks 28 and the lowest value was detected at weeks 1 week. LH-stimulated testosterone production per testis in vitro increased gradually with age from 1 to 32 weeks and decreased significantly from 44 weeks to 64 weeks of age.

• Journal of Animal Science and Technology
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• v.52 no.3
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• pp.175-186
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• 2010

The aim of this study was to analyze the proteome expressions of proliferating stromal vascular cells from Hanwoo omental, subcutaneous and intramuscular depots subjected to hormone deprivation and IGF-1, Estradiol-$17{\beta}$ addition. For hormone deprivation or addition studies, the cells were either grown in 10% charcoal-dextran stripped fetal bovine serum (CD-FBS) or in 10% FBS supplemented medium. Further, to analyze the effect of insulin like growth factor (IGF-1) and $17\beta$-Estradiol (E2), cells were grown in 10% CD-FBS containing IGF-1 (10 ng/ml) or E2 (10 nM). The results showed that hormone deprivation had a negative impact on proliferation among the cells from all depots without any growth difference. On comparison of proliferation levels, higher levels were observed in cells that were grown in 10% FBS than in 10% CD-FBS alone or with IGF-1/E2. Proteome expression from preadipocytes grown in hormone deprivation conditions were compared by 2D-DIGE and MALDIToF/ToF. A total of twelve different proteins were found to be differentially expressed under hormone deprivation conditions. Further, our proteomic analysis with DIGE under IGF-1 and E2 addition revealed four proteins with differential expression levels. Moreover, the results highlighted in this study offer a role for each differentially expressed protein with respect to their effect in positive or negative regulation on proliferation.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.335-341
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• 2003

Carcass weight and backfat thickness are two of important elements in determining the carcass trait in pigs and are studied on animal genetics, nutrition, and endocrinology. Growth factors stimulate or inhibit the proliferation and differentiation of various cells. In particular, insulin-like growth factors (IGFs), transforming growth factor (TGF)-$\beta$, and epidermal growth factor (EGF) are involved in the growth and maintenance of muscle. Also, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol are known to be related to the obesity and subcutaneous fat depth in pigs. Therefore, this study was performed to relate growth factors (IGFs, TGF-${\beta}1$, and EGF) and hormones (cortisol and DHEA-S) concentrations at antemortem and postmortem periods to carcass traits including carcass weight and backfat thickness. Blood and m. Longissimus were collected in pigs at antemortem (30 days before slaughter) and postmortem periods. After slaughtered, carcass weight and backfat thickness were measured. Growth factors and hormones in serum and m. Longissimus were measured by radioimmunoassay or enzyme-linked imuunosorbent assay. Before antemortem period, serum IGF-I and -II concentrations were positively correlated with the carcass weight and backfat thickness in gilts, and the concentrations of TGF- ${\beta}1$ and cortisol in barrows show the correlation with only carcass weight. Also, the positive correlations of muscular IGFs and TGF-${\beta}1$ at postmortem 45 min with the carcass weight and backfat thickness were detected. Consequently, these results suggest that the serum and muscular endocrine factors are involved in the carcass weight and backfat thickness in pigs.

• Tuberculosis and Respiratory Diseases
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• v.52 no.4
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• pp.338-345
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• 2002

Background : Coal workers' pneumoconiosis(CWP) is a fibrotic lung disease resulting from the chronic inhalation of coal dust. Various cytokines and growth factors secreted from macrophages and monocytes play a key role in the pathogenesis of pneumoconiosis. The platelet-derived growth factor (PDGF)-BB and the insulin-like growth factor(IGF)-1 secreated from the macrophages and monocytes are believed to stimulate the accumulation of mesenchymal cells and fibrosis of the lower respiratory tract that is observed in fibrotic lung disease. The serum concentraion of PDGF-BB and IGF-1 in 30 CWP patients and 10 healthy controls were measured in order to determine if PDGF-BB and IGF-1 can be used as sensitive biomarkers in CWP. Method : Serum was collected from 30 patients with CWP(13 with simple CWP and 17 with complicated CWP) and 10 healthy controls. The serum concentrations of PDGF-BB and IGF-1 were measured using ELISA (R&D system, Minneapolis, MN). Results : The serum PDGF-BB concentration in patients with complicated CWP($10083.76{\pm}639.07pg/mL$) was significantly higher than in the patients with simple CWP ($8493.88{\pm}848.51pg/mL$) and the healthy controls ($3726.17{\pm}292.20pg/mL$) (p<0.05). Compared to the healthy controls ($413.40{\pm}1.94ng/mL$), there was no significant difference in the serum IGF-1 concentration in patients with simple ($366.77{\pm}183.67ng/mL$) and complicated CWP ($403.18{\pm}15.39ng/mL$) (p>0.05). Conclusion : These results show the important role of the PDGF-BB mediated pathways in the pathogenesis of CWP. These data suggests that the PDGF-BB serum concentration is a useful biomarkers of the fibrotic extent in CWP patients.

• Fisheries and Aquatic Sciences
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• v.25 no.8
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• pp.450-461
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• 2022

A randomized, double-blind, and placebo-controlled clinical study was used to determine the cognitive functions related to working memory (WM) and antioxidant properties of fermented Laminaria japonica (FLJ) on healthy volunteers. Eighty participants were divided into a placebo group (n = 40) and FLJ group (n = 40) that received FLJ (1.5 g/day) for 6 weeks. Memory-related blood indices (brain-derived neurotrophic factor, BDNF; angiotensin-converting enzyme; human growth hormone, HGH; insulin-like growth factor-1, IGF-1) and antioxidant function-related indices (catalase, CAT; malondialdehyde, MDA; 8-oxo-2'-deoxyguanosine, 8-oxo-dG; thiobarbituric acid reactive substances, TBARS) were determined before and after the trial. In addition, standardized cognitive tests were conducted using the Cambridge Neuropsychological Test Automated Batteries. Furthermore, the Korean Wechsler Adult Intelligence Scale (K-WAIS)-IV, and the Korean version of the Montreal Cognitive Assessment (MoCA-K) were used to assess the pre and post intake changes on WM-related properties. According to the results, FLJ significantly increased the level of CAT, BDNF, HGH, and IGF-1. FLJ reduced the level of TBARS, MDA, and 8-oxo-dG in serum. Furthermore, FLJ improved physical activities related to cognitive functions such as K-WAIS-IV, MoCA-K, Paired Associates Learning, and Spatial Working Memory compared to the placebo group. Our results suggest that FLJ is a potential candidate to develop functional materials reflecting its capability to induce antioxidant mechanisms together with WM-related indices.