• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.685-690
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• 1999

The insulin like growth factors(IGFs) are bound to several binding proteins(IGFBPs) that appear to regulate IGF transfort, receptor binding, and its action. The concentrations of these peptides are regulated by quantity and nutritional quality of dietary proteins. The aim of this study was to compare the effects of two diets, which differed in their protein source, Carassius carassius(CC), Carassius carassius hot water extract(CCHE), for 4 weeks. Body weight was significantly increased in the CC group(74.14$\pm$12.00 to 266.31$\pm$36.62g; p<0.01). Likewise, IGF I concentration of CC group(101.76$\pm$15.90 ng/ml) was significantly higher than that of CCHE group(38.50$\pm$ 11.20ng/ml; p<0.05). By western immunoblot analysis, especially IGFBP 1, 2 levels are increased, whereas IGFBP 3 level was de creased in CCHE group. After extraction of browning material from each samples, the extractive was filtered and absorbance at 420nm was measured. The absorbance of CCHE group was significantly higher than that of CC group. These results suggest that IGF I can be employed as an index of protein metabolism, particulary as a simple index in the assessing the status of protein nutrition.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.119-125
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• 2006

To understand the comprehensive mechanisms of biological function for insulin-like growth factor-I (IGF-I) in vertebrates, we have investigated the cDNA sequence of this gene in the korean rockfish (Sebastes schlegeli). The mature form of korean rockfish IGF-I was found to be comprised of 67 amino acid residues, showing about a 7 kDa molecular weight. In this study, we used the polymerase chain reaction (PCR) to obtain a korean rockfish IGF-I (KR IGF-I) cDNA fragment, and methods of rapid amplification of cDNA ends (RACE) to obtain a full length of the KR IGF-I sequence. The KR IGF-I encoded for a predicted amino acid sequence showed identities of 93.6 %, 90.7 %, and 85.4 % in comparison with flounder, chinook salmon, and human IGF-I, respectively. To obtain recombinant biologically active polypeptides, korean rockfish B-C-A-D domains were amplified using the PCR, then the isolated cDNA was expressed in the E. coli BL21(DE3). The recombinant KR IGF-I protein biological function was measured by stimulation of [$^3H$] thymidine incorporation, suggesting the cDNA codes for the korean rockfish proIGF-I.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.733-741
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• 2007

The effects of intra-duodenal infusion of methionine (Met), lysine (Lys) and leucine (Leu) on dry matter intake (DMI), the concentrations of insulin-like growth factor I (IGF-I), growth hormone (GH) and insulin in plasma, and liver IGF-I mRNA level were investigated in two experiments for Liuyang Black growing wether goats. In Experiment 1, three goats ($10.0{\pm}0.1$ kg) were fitted with ruminal, proximal duodenal and terminal ileal fistulaes to determine the infusion amounts of Met, Lys and Leu at the duodenum according to essential amino acid flows into the duodenum and their apparent digestibility. The infusion amounts were 0.77 g/d, 0.91 g/d and 0.58 g/d respectively. In Experiment 2, 4 groups of goats (($10.0{\pm}0.2$ kg) for each group, were cannulated at the duodenum, and were infused with a mixture of Met, Lys and Leu (Control), or mixtures with 21% Met, Lys or Leu replaced with glutamate respectively on a nitrogenous basis. The replacement of 21% Met, Lys or Leu with glutamate did not affect intakes of maize stover, concentrate or both (p>0.05) when compared with the control. The replacement of 21% Met or Lys significantly (p<0.05) reduced plasma GH, insulin and IGF-I concentrations and liver IGF-I mRNA level. The replacement of 21% Leu with glutamate reduced (p<0.05) plasma IGF-I concentration only, but not plasma insulin and GH, as well as liver IGF-I mRNA level (p>0.05). The close relationships between supplying Met and Lys in the lumen of the duodenum and plasma IGF-I, GH and insulin concentrations, as well as liver IGF-I mRNA level in this study indicate that the effects of the limiting amino acids on nutrition of animals are likely intermediated via their effects on these hormones, and these hormone profiles could be used as intermediate markers for the limiting order of amino acids.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.147-154
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• 2014

This review focuses on modulation of growth hormone (GH) and its downstream actions on periparturient dairy cows undergoing physiological and metabolic adaptations. During the periparturient period, cows experience a negative energy balance implicating that the feed intake does not meet the total energy demand for the onset of lactation. To regulate this metabolic condition, key hormones of somatotropic axis such as GH, IGF-I and insulin must coordinate adaptations required for the preservation of metabolic homeostasis. The hepatic GHR1A transcript and GHR protein are reduced at parturition, but recovers on postpartum. However, plasma IGF-I concentration remains low even though hepatic abundance of the GHR and IGF-I mRNA return to pre-calving value. This might be caused by alternation in IGFBPs and ALS genes, which consequently affect the plasma IGF-I stability. Plasma insulin level declines in a parallel manner with the decrease in plasma IGF-I after parturition. Increased GH stimulates the lipolytic effects and hepatic glucose synthesis to meet the energy requirement for mammary lactose synthesis, suggesting that GH antagonizes insulin-dependent glucose uptake and attenuates insulin action to decrease gluconeogenesis.

• KSBB Journal
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• v.18 no.4
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• pp.329-334
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• 2003

The present study was aimed at investigating the regulatory mechanism in tissue-specific expression of insulin-like growth factor-I (IGF-I) gene. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA prepared from rat liver or brain of various ages. The levels of IGF-I transcripts were increased in liver gradually after birth, but decreased in brain. By using an oligonucleotide (FRE) corresponding to the C/EBP binding site of the rat IGF-I exon 1, multiple forms of C/EBP${\alpha}$ and C/EBP${\beta}$ proteins, which have DNA-binding activity, were detected in the rat liver or brain. Western immunoblot and southwestern analyses show that p42$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\alpha}$/, p35$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\beta}$/, and p35$\^$C/EBP${\beta}$ form specific complexes with the IGF-I exon 1 oligonucleotide in liver nuclear extract and that p42$\^$C/EBP${\alpha}$/ and p38$\^$C/EBP${\beta}$/ form complexes in brain. These data suggest that the formation of FRE-C/EBP isoform complexes may play important roles in the tissue-specific regulation of IGF-I gene expression.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5675-5680
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• 2013

Background: Preexisting type 2 diabetes mellitus (T2DM) affects the prognosis and mortality of patients with some cancers. Insulin like growth factor (IGF) and insulin receptor (IR) signaling axes play important roles in both cancer and diabetes development. We aimed to explore the expression characteristics of proteins in IGF/IR axis in non-small cell lung cancer (NSCLC) cases with preexisting T2DM. Methods: Fifty-five NSCLC patients with preexisting T2DM were retrospectively included and matched by 55 NSCLC without diabetes at a 1:1 ratio. The expression of proteins in IGF/IR axis was detected by immunohistochemical staining. Clinicopathological data were collected to analyze their relationship with the protein expression. Results: Both IGF 1 receptor (IGF-1R) and insulin receptor substrate 2 (IRS-2) showed higher expression in the NSCLC with T2DM group, compared with those without T2DM. The high expression of IGF-1R and IRS-2 were found to be negatively associated with lymph node metastases and T staging in the T2DM group, respectively, and IRS-2 expression was also found more in the subgroup whose T2DM duration was more than 4 years. No difference was detected in the expression of IRS-1, IGF-1, IGF-2, IGFBP3, IR and mTOR between groups with or without T2DM. Conclusion: Our study found higher expression of IGF-1R and IRS-2 proteins in NSCLC patients with preexisting T2DM, and that there was an association with early stage NSCLC, which suggested that IGF signaling may play an important early event in development of NSCLC associated with diabetes.

• Biomedical Science Letters
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• v.21 no.2
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• pp.126-130
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• 2015

There are several studies that show hypothermia improves cellular ischemia damages on experimental and clinical bases. However, its exact molecular mechanisms are unclear. In this study, we demonstrate that hypothermia induced insulin-like growth factor 1 (IGF1) gene expression, and its expression was dramatically decreased under ischemic insults. It was also demonstrated that hypothermia activated endoplasmic reticulum (ER) stress sensors especially both the phosphorylation of $eIF2{\alpha}$ (eukaryotic translation initiation factor 2 alpha) and ATF6 (activating transcription factor-6) proteolytic cleavage. However, the factors of apoptosis and autophagy were not associated with hypothermia. We suggest that hypothermia-treated IGF1 gene expression after ischemia may show a good possibility for the development of treatments and diagnostic methods in cerebral ischemic damages.

• BMB Reports
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• v.52 no.1
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• pp.70-85
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• 2019

Reduction of insulin/insulin-like growth factor 1 (IGF1) signaling (IIS) extends the lifespan of various species. So far, several longevity mouse models have been developed containing mutations related to growth signaling deficiency by targeting growth hormone (GH), IGF1, IGF1 receptor, insulin receptor, and insulin receptor substrate. In addition, p70 ribosomal protein S6 kinase 1 (S6K1) knockout leads to lifespan extension. S6K1 encodes an important kinase in the regulation of cell growth. S6K1 is regulated by mechanistic target of rapamycin (mTOR) complex 1. The v-myc myelocytomatosis viral oncogene homolog (MYC)-deficient mice also exhibits a longevity phenotype. The gene expression profiles of these mice models have been measured to identify their longevity mechanisms. Here, we summarize our knowledge of long-lived mouse models related to growth and discuss phenotypic characteristics, including organ-specific gene expression patterns.

• KSBB Journal
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• v.17 no.4
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• pp.403-408
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• 2002

For stimulating the in vivo secretion of IGF-1 (insulin-like growth factor-1) which is well known to promote the various physiological actions in human body, the natural herbal extract, YGF251 (young growth factor 251), was developed and evaluated for its effect as IGF-1 secretagogue in this study. The clinical study was peformed as double blind test, and 31 adult female and male volunteers between the age of 40 and 70 were investigated for their changes of concentration of IGF-1 , insulin level, weight, blood pressure, and liver and kidney functions. As the result of paired sample test on the change of the concentration of IGF-1, in YGF251 treated group, it was 245.6 ng/mL before dosing. The concentration of IGF-1 was increased to 269.3 ng/mL after a month and to 275.6 ng/mL after two months, and both were statistically significant (p〈0.05). While in control group, the concentration of IGF-1 was 280.0 ng/mL before dosing, but decreased to 239.2 ng/mL after a month and to 230.2 ng/mL after two months, and both were also statistically significant (p〈0.05). In YGF251 treated group, the concentration of insulin in blood increased about 2 times after a month dosing as an average level, but in control group, it showed a decrease of 36% compared with before dosing. And there were little changes regarding to the measured weight and blood pressure. Various measured data in order to observe the alteration in liver and kidney functions by the administration of YGF251 showed a little change within measuring error range.

• Journal of Life Science
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• v.22 no.12
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• pp.1651-1657
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• 2012

Plectin and microtubule actin cross-linking factor 1 (MACF1) are architectural proteins that contribute to the function of skeletal muscle as generators of mechanical force. However, the influence of insulin- like growth factor-I (IGF-I), a master regulator of skeletal muscle cells, on plectin and MACF1 in skeletal muscle cells has not been demonstrated. The effect of IGF-I on plectin and MACF1 gene expression was investigated by treating differentiated C2C12 murine skeletal muscle cells with 20 ng/ml of IGF-I at different time points. The IGF-I treatment increased plectin protein expression in a dose-dependent manner. The mRNA level of plectin was measured by real-time quantitative PCR to determine if plectin induction was regulated pretranslationally. IGF-I treatment resulted in a very rapid induction of plectin mRNA transcript in C2C12 myotubes. Plectin mRNA increased by 140 and 180% after 24 and 48 hours of IGF-I treatment, respectively, and returned to the control level after 72 hours of IGF-I treatment. MACF1 mRNA increased 86 and 90% after 24 and 48 hours of IGF-I treat-ment, respectively, and returned to the control level after 72 hours of IGF-I treatment. These results suggested that the plectin gene is regulated pretranslationally by IGF-I in skeletal muscle cells. In conclusion, IGF-I induces a rapid transcriptional modification of the plectin and MACF1 genes in C2C12 skeletal muscle cells and has modulating effects on a cytolinker protein as well as on contractile proteins.