• Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.224-230
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• 2010

Growth hormone (GH) is known as one of the main osmoregulators in euryhaline teleosts during seawater (SW) adaptation. Many of the physiological actions of GH are mediated through insulin-like growth factor-I (IGF-I), and the GH/IGF-I axis is associated with osmoregulation of fish during SW acclimation. However, little information is available on the response of fish IGF-II to hyperosmotic stress. Here we present the first cloned IGF-I and IGF-II cDNAs of marine medaka, Oryzias dancena, and an analysis of the molecular characteristics of the genes. The marine medaka IGF-I cDNA is 1,340 bp long with a 257-bp 5' untranslated region (UTR), a 528 bp 3' UTR, and a 555-bp open reading frame (ORF) encoding a propeptide of 184 amino acid (aa) residues. The full-length marine medaka IGF-II cDNA consists of a 639 bp ORF encoding 212 aa, a 109 bp 5' UTR, and a 416 bp 3' UTR. Homology comparison of the deduced aa sequences with other IGF-Is and IGF-IIs showed that these genes in marine medaka shared high structural homology with orthologs from other teleost as well as mammalian species, suggesting high conservation of IGFs throughout vertebrates. The IGF-I mRNA level increased following transfer of marine medaka from freshwater (FW) to SW, and the expression level was higher than that of the control group, which was maintained in FW. This significantly elevated IGF-I level was maintained throughout the experiment (14 days), suggesting that in marine medaka, IGF-I is deeply involved in the adaptation to abrupt salinity change. In contrast to IGF-I, the increased level of marine medaka IGF-II mRNA was only maintained for a short period, and quickly returned a level similar to that of the control group, suggesting that marine medaka IGF-II might be a gene that responds to acute stress or one that produces a supplemental protein to assist with the osmoregulatory function of IGF-I during an early phase of salinity change.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.822-832
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• 2018

Objective To determine the socio-demographic, psychologic, hematologic, or other relevant factors associated with hand grip strength in Korean farmers. Methods A total of 528 healthy Korean farmers were enrolled. Hand grip strength was measured in both hands using a hydraulic dynamometer. Socio-demographic characteristics were assessed and anthropometric measurements were obtained. Psycho-cognitive measurements such as sleep quality (Pittsburgh Sleep Quality Index) and Go/No-Go test response time were conducted. In addition to physical measurements, serologic parameters including insulin-like growth factor 1 were measured. The factors associated with hand grip strength were analyzed using multiple linear regression analysis after adjusting for age, height, and weight. Results The mean hand grip strength was associated with the Pittsburgh Sleep Quality Index total score (${\beta}=-0.12$, p=0.01), the Go/No-Go test response time (${\beta}=-0.18$, p=0.001), vitamin D (${\beta}=0.12$, p=0.02), and insulin-like growth factor 1 levels (${\beta}=0.1$, p=0.045). In female farmers, hand grip strength was only associated with the Pittsburgh Sleep Quality Index total score (${\beta}=-0.32$, p<0.001). Conclusion The results of this study demonstrate that hand grip strength was associated with sleep quality and attention in Korean farmers.

• Animal Bioscience
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• v.34 no.1
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• pp.143-153
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• 2021

Objective: To explore the molecular mechanisms of fatty liver hemorrhagic syndrome (FLHS) in laying hens, an experiment was conducted to reveal the differences in histopathological observation and gene expression between FLHS group and normal group. Methods: We compared the histopathological difference using hematoxylin and eosin staining and proceeded with RNA sequencing of adipose tissue to search differentially expressed genes and enriched biological processes and pathways. Then we validated the mRNA expression levels by real-time polymerase chain reaction and quantified protein levels in the circulation by enzyme-linked immunosorbent assay. Results: We identified 100 differentially expressed transcripts corresponding to 66 genes (DEGs) were identified between FLHS-affected group and normal group. Seven DEGs were significantly enriched in the immune response process and lipid metabolic process, including phospholipase A2 group V, WAP kunitz and netrin domain containing 2, delta 4-desaturase sphingolipid 2, perilipin 3, interleukin-6 (IL-6), ciliary neurotrophic factor (CNTF), and suppressor of cytokine signaling 3 (SOCS3). And these genes could be the targets of immune response and be involved in metabolic homeostasis during the process of FLHS in laying hens. Based on functional categories of the DEGs, we further proposed a model to explain the etiology and pathogenesis of FLHS. IL-6 and SOCS3 mediate inflammatory responses and the satiety hormone of leptin, induce dysfunction of Jak-STAT signaling pathway, leading to insulin resistance and lipid metabolic disorders. Conversely, CNTF may reduce tissue destruction during inflammatory attacks and confer protection from inflammation-induced insulin resistance in FLHS chickens. Conclusion: These findings highlight the therapeutic implications of targeting the JAK-STAT pathway. Inhibition of IL6 and SOCS3 and facilitation of CNTF could serve as a favorable strategy to enhance insulin action and improve glucose homoeostasis, which are of importance for treating obesity-related disorders for chickens.

• Molecules and Cells
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• v.28 no.5
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• pp.495-499
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• 2009

Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) are well known effectors of skeletal muscle, the molecular mechanism by which signaling pathways integrating AR and IGF-I in skeletal muscle cells has not been previously examined. In this study, the role of PI3K/Akt on IGF-I-induced gene expression and activation of AR in skeletal muscle cells was investigated. C2C12 cells were treated with IGF-I in the absence or presence of inhibitors of PI3K/Akt pathway (LY294002 and Wortmannin). Inhibition of the PI3K/Akt pathway with LY294002 or Wortmannin led to a significant decrease in IGF-I-induced AR phosphorylation and total AR protein expression. Furthermore, IGF-I-induced AR mRNA and skeletal ${\alpha}-actin$ mRNA were blocked by LY294002 or Wortmannin. Confocal images showed that IGF-I-induced AR translocation from cytosol to nucleus was inhibited significantly in response to treatment with LY294002 or Wortmannin. The present results suggest that modulating effect of IGF-I on AR gene expression and activation in C2C12 mouse skeletal muscle cells is mediated at least in part by the PI3K/Akt pathway.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.70-84
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• 2022

Purpose: Skeletal muscles display significant heterogeneity in metabolic responses, owing to the composition of metabolically distinct fiber types. Recently, numerous studies have reported that in skeletal muscles, suppression of genes related to fatty acid channeling alters the triacylglycerol (TAG) synthesis and switches the energy substrates. However, such responses may differ, depending on the type of muscle fiber. Hence, we conducted in vitro and animal studies to compare the metabolic responses of different types of skeletal muscle fibers to the deficiency of fatty acyl-CoA synthetase (Acsl)6, one of the main fatty acid-activating enzymes. Methods: Differentiated skeletal myotubes were transfected with selected Acsl6 short interfering RNA (siRNA), and C57BL/6J mice were subjected to siRNA to induce Acsl6 deficiency. TAG accumulation and expression levels of insulin signaling proteins in response to acute glucose supplementation were measured in immortalized cell-based skeletal myotubes, oxidative muscles (OM), and glycolytic muscles (GM) derived from the animals. Results: Under conditions of high glucose supplementation, suppression of the Acsl6 gene resulted in decreased TAG and glycogen synthesis in the C2C12 skeletal myotubes. The expression of Glut4, a glucose transporter, was similarly downregulated. In the animal study, the level of TAG accumulation in OM was higher than levels determined in GM. However, a similar decrease in TAG accumulation was obtained in the two muscle types in response to Acsl6 suppression. Moreover, Acsl6 suppression enhanced the phosphorylation of insulin signaling proteins (Foxo-1, mTORc-1) only in GM, while no such changes were observed in OM. In addition, the induction ratio of phosphorylated proteins in response to glucose or Acsl6 suppression was significantly higher in GM than in OM. Conclusion: The results of this study demonstrate that Acsl6 differentially regulates the energy metabolism of skeletal muscles in response to glucose supplementation, thereby indicating that the fiber type or fiber composition of mixed muscles may skew the results of metabolic studies.

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.19-27
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• 1990

This investigation was undertaken to clarify the in vitro effect of the various stimulations, such as exercise(E), insulin(I), direct electrical stimulation(EST) and the combinations of the above, on the glucose incorporation into glycogen molecules (glycogen synthesis) of the normal slow(soleus) and fast twitch(plantaris) muscles, and the different responses of slow and fast twitch muscles to persistent overloads causing compensatory muscle hypertrophy. In resting state, slow twitch muscle has greater capacity for glycogen synthesis than fast twitch muscle, and responses of different muscle to various stimuli were differ as follows : In slow twitch muscle, the glycogen synthesis was increased by insulin, and electrical stimulation but not increased by exercise ; exercise increased insulin sensitivity and the effect of electrical stimulation. Whereas the glycogen synthesis in fast twitch muscle was increased only by the stimuli combined with E and EST, and E, I, and EST. As the result of removal of synergistic muscle, both muscles were hypertropied, and the degree of hypertrophy in response to persistent overload was higher in fast twitch muscle(182%) than slow twitch muscle(151%). In hypertrophied muscles, glycogen synthesis of soleus in any groups was lower than that of the control, but similar in plantaris. In conclusions, there were marked heterogeneity in defferent muscle fiber in the effects of exercise and insulin addition and electrical stimulation on muscle glycogen synthesis, and fast twitch muscle may be adapted more easily to that kind of persistent overload than slow twitch muscle.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.154-160
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• 1990

Hydroxypropyl methacrylate polymeric membranes having tertiary amine moiety were prepared to control the release rate of insulin in response to the concentration of glucose. Hydroxypropyl methacrylate was copolymerized with N, N'-diethylaminoethylacrylate. Its water content was increased with decreasing the pH of the medium and was reversible with variation of the pH of the medium. The permeation coefficient of insulin through copolymer membrane was also increased with decreasing the pH of the medium. Combining this copolymer membrane and the glucose oxidase immobilized membrane as a sensor for glucose, composite membrane was prepared. The permeability of this composite membrane was increased with addition of glucose.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.739-745
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• 2006

Changes in the levels of analytes in the blood and urine of a rodent animal model were taken as a measure of the hypoglycemic effects of a diet containing fermented chaga mushroom. These studies were conducted using the genetically manipulated diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The effects of 8-week long diets that included either fermented (FCM) or non-fermented (CM) chaga mushroom powder (5% in the diet) on the OLETF rat were compared to the normal diet fed OLETF rat and the non-diabetic Long-Evans Tokushima Otsuka (LETO) rat. Hypoglycemia was tracked by measuring serum and urine concentrations of glucose, insulin, fructosamine, and leptin. Serum and urine levels of glucose, fructosamine, and leptin in the OLETF rats were higher than in LETO rats when fed normal diets but insulin levels did not differ between the two animal groups. The FCM rats were characterized by dramatically low levels of serum glucose and leptin in the OLETF rats whereas the levels of fructosamine and urine glucose trended lower in response to FCM. The serum leptin level in the CM-fed OLETF rat was also lower than that in the normal diet fed OLETF control. Serum concentrations of insulin in the OLETF rats were higher following FCM or CM feeding compared to the normal diet. These observations imply that (a) a dietary supplement of fermented chaga mushroom may contribute to a hypoglycemic effect in the OLETF rat, and (b) the increased blood insulin concentration following 8 weeks of an FCM diet may be important to the noted improvement in hyperglycemia.

• Nuclear Engineering and Technology
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• v.9 no.4
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• pp.203-210
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• 1977

Using dimethylsulfoxide (DMSO) as a labelling aid, insulin--$^{126}$ I of radioimmunoassay use has been effectively prepared. A small amount of DMSO was added to usual labelling mixture ana the reaction time was controled. The labelled insulin obtained in such a way showed improved bindabilities to the antibody and thus expressed larger dose-gradients in the plots of standard dose-response curves even though the labelling rate was decreased to some extent. However, by extending the reaction time to about 1 min, average labelling yield of 30% could be obtained. The average increase of bindability (B/F) in definite antiserum dilution was 2.5 comparing with 1.5 obtained in the absence of DMSO. Thus, the net bindability increase was 70% of those obtained in tile absence of DMSO. By means of a NMR spectrometry, it has been confirmed that the DMSO in the labelling mixtutre is converted to dimethylsulfone by chloramine-T. The results, generally agreed with the Stags's postulation, were discussed in view of a competitive oxidation of DMSO with disulfide linkages of the insulin molecule by the chloramine-T.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.2
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• pp.187-196
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• 2021

Purpose: The rising prevalence of childhood obesity in the past decades has caused non-alcoholic fatty liver disease (NAFLD) to become the most common cause of pediatric chronic liver disease worldwide. This study was aimed at determining the effect of vitamin D (Vit D) on ultrasonography and laboratory indices of NAFLD and some blood biochemical indicators in children. Methods: In this interventional study liver ultrasonography was performed in 200 children with overweight and obesity. A 108 had fatty liver among which 101 were randomly divided into two groups of study (n=51) and control (n=50). The study group was treated with Vit D, 50000 U once a week whereas the control group received placebo with the same dose and package, both for 12 weeks. At the end of the intervention lab tests and ultrasound study was performed once again to evaluate the response to treatment. Results: It was found out that Vit D supplementation improved the fatty liver grade in the study group. The mean changes in hemoglobin (Hb), uric acid, highdensity lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), insulin, albumin and alanine aminotransferase (ALT) was significantly higher in the study group compared to controls (p<0.05). After the intervention and means adjustment, a significant difference was obtained in HDL-C, insulin, LDL-C and homeostasis model assessment of insulin resistance (HOMA-IR) between the two groups. Conclusion: Vit D supplementation in addition to improving the fatty liver grade in ultrasonography and increasing the blood Vit D level, increases the HDL and Hb level besides decreasing uric acid, LDL, HOMA-IR, insulin and ALT levels.