• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.1010-1018
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• 2006

A glucose clamp technique was used to investigate the effects of non-protein energy intake on tissue responsiveness and sensitivity to insulin for glucose metabolism in intact adults male goats. Three goats were fed diets at 1.0, 1.5 and 2.0 times of ME for maintenance, each for 21 d. Crude protein intake was 1.5 times of maintenance requirement in each treatment. Tissue responsiveness and sensitivity to insulin were evaluated using a hyperinsulinemic euglycemic clamp technique with four levels of insulin infusion, beginning at 13 h after feeding. Concentrations of plasma metabolites and insulin were also measured at 3, 6 and 13 h after feeding, for evaluating effects of non-protein energy intake on the metabolic status of the animals. Increasing non-protein energy intake prevented an increase in plasma NEFA concentration at 13 h after feeding (p = 0.03). Plasma urea-nitrogen and total amino-nitrogen concentrations decreased (p<0.01) and increased (p = 0.03), respectively, with increasing non-protein energy intake across time relating to feeding. Plasma insulin concentration was unaffected (p = 0.43) by non-protein energy intake regardless of time relating to feeding. In the glucose clamp experiment, increasing non-protein energy intake decreased numerically (p = 0.12) the plasma insulin concentration at half-maximal glucose infusion rate (insulin sensitivity), but did not affect (p = 0.60) maximal glucose infusion rate (tissue responsiveness to insulin). The present results suggest that an increase in non-protein energy intake may enhance insulin sensitivity for glucose metabolism, unlike responsiveness to insulin, in adult male goats. The possible enhancement in insulin sensitivity may play a role in establishing anabolic status in the body, when excess energy is supplied to the body.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.1
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• pp.41-45
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• 1991

Insulin responsiveness to glucose and tissue responsiveness to insulin, using the hyperglycemic clamp and the hyperinsulinemic euglycemic clamp techniques, were compared among cows, sheep and pigs. The plasma insulin concentrations during the hyperglaycemic clamp period were highest (p < 0.05) in cows, followed by sheep and pigs. The glucose infusion rate in the hyperinsulinemic euglycemic clamp technique was greater (p < 0.01) in pigs than in cows and sheep. These results suggest responsiveness to insulin is higher in pigs than in cows and sheep.

• Biotechnology and Bioprocess Engineering:BBE
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• v.1 no.1
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• pp.9-12
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• 1996

In order to produce the single chain precursor of a novel human insulin analogue, (B30-Homoserine) insulin, the fermentative behaviors of Escherichia coli JM103 were studied, which harbors pKBA plasmid carrying a hybrid gene in which the gene for a single chain precursor was fused with lacZ gene under tac promoter. The maximal induction of gene expression was achieved when more than 0.05 mM of isopropyl-$\beta$-D-thiogalactopyranoside(IPTG) was supplemented to fermentation medium after 4 h cultivation of E. coli, and followed by longer than 2-h fermentation. The hybrid protein of the single chain insulin precursor was isolated from cytoplasmic inclusion bodies by dissolving in 8M urea solution, and purified through DEAE-Sephacel and Sephadex G-200 column chromatographies with a recovery of 35%. The finally purified hybrid protein showed a single band on sodium dodecyl sulfate-polyacrylamide gel.

• Proceedings of the Ginseng society Conference
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• 2006.05a
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• pp.69-70
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• 2006

Purpose: Panaxadiols are more potent than panaxatriols as far as insulin secretory activity is concerned. In this study, we examined insulin secretory activity and mechanism of compound K (CK), a major intestinal bacterial metabolite of ginsenosides. Method: Insulin secretory activity of CK was examined using pancreatic beta cells and in Oral Glucose Tolerance Test assay. In addition, insulin secretory mechanism was studied in terms of calcium dependent or independent pathways. Results: In vitro, CK enhanced the insulin secretion concentration-dependently when compared to glucose-stimulated control cells. Insulin secretory mechanism of CK seems to block ATP sensitive K channels, which was confirmed by diazoxide (K channel opener) but, insulin resistance ameliorating activity of CK can't be ruled out. In vivo, CK showed hypoglycemic effect in OGTT.

• Journal of Nutrition and Health
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• v.35 no.7
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• pp.737-742
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• 2002

To evaluate the effect of obesity on serum leptin and insulin levels in 80 elementary school children (aged 10.8 yr, 47 boys, 33 girls), we collected the anthropometric data and measured serum leptin and insulin levels. Serum leptin level and insulin resistance are known as factors which are associated with obesity and obesity related diseases such as diabetes, cardiovascular disease, hypertension. The results were as follows. The serum levels of insulin (p＜0.001), leptin (p＜0.001) and HOM $A_{IR}$ (p＜0.001) in obese group were significantly higher than those of other groups. The obesity indices correlated significantly to serum levels of insulin and leptin, but not to fasting glucose level. These results suggested that circulating leptin and insulin concentrations may act as a humoral signal indicator to adiposity-associated metabolic disorder in elementary school children.

• Molecules and Cells
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• v.38 no.4
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• pp.297-303
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• 2015

Skeletal muscle insulin resistance, which increases the risk for developing various metabolic diseases, including type 2 diabetes, is a common metabolic disorder in obesity and aging. If potential treatments are to be developed to treat insulin resistance, then it is important to fully understand insulin signaling and glucose metabolism. While recent large-scale "omics" studies have revealed the acetylome to be comparable in size to the phosphorylome, the acetylation of insulin signaling proteins and its functional relevance to insulin-stimulated glucose transport and glucose metabolism is not fully understood. In this Mini Review we discuss the acetylation status of proteins involved in the insulin signaling pathway and review their potential effect on, and relevance to, insulin action in skeletal muscle.

• Journal of Pharmaceutical Investigation
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• v.16 no.3
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• pp.89-100
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• 1986

Although insulin has been available for the treatment of diabetes mellitus for more than half a centry, the deficiency of conventional insulin therapy for diabetic patients have, to this date, not been satisfactorily overcome by any method. The development of potential delivery systems for insulin is highly important to prevent excessive fluctuation of plasma glucose levels, which results in long term complications in the diabetic. There are three major approaches toward development of glucose responding insulin delivery systems: A bioengineering approach is to devise mechanical components capable of releasing insulin in amounts appropriate to varying blood-glucose requirements. A biological approach relies upon cultured, living pancreatic beta cells encapsulated to constitute an insulin delivery unit. A biochemical approach is to synthesize a stable and biologically active glycosylated insulin that is complementary to the binding sites of lectin. This paper will cover several specific areas, including pancreatic transplantation(total or isolated islet cells), artificial pancreases(bioengineering or biological approach), controlled delivery system, glucose sensitive membrane systems, and a self-regulating insulin delivery system.

• International Journal of Contents
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• v.9 no.3
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• pp.62-66
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• 2013

Insulin resistance is a risk factor for stroke or recurrent stroke. Sedentary behavior increases insulin resistance. This study aimed to identify the relationship between physical impairments and functions and insulin resistance, examining which physical impairments specifically influence insulin resistance the most. The subjects of this study were 63 stroke patients. The subject's insulin resistance and physical impairments and functions were measured using the Chedoke-McMaster Stroke Assessment (CMSA) and Stroke Impairment Assessment Set (SIAS). The study results exhibited that insulin resistance is statistically significantly related to the variable of foot according to the CMSA(r=.95, p<.05) and to the variable of lower extremity sensory function (touch) in relation to the SIAS(r=.91, p<.05). This study also revealed close correlations between insulin resistance and the variables of ankle control(${\beta}=-1.05$, p<.05) and low extremity tactile sensations(${\beta}=-1.82$, p<.05).

• YAKHAK HOEJI
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• v.52 no.3
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• pp.182-187
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• 2008

Salicylate (SA) was shown to alleviate insulin resistance. Here, we showed that SA inhibited Ser731 phosphorylation of insulin receptor substrate 1 (IRS1) and S6 kinase activation, and enhanced tyrosine phosphorylation of IRS1 in response to insulin or amino acid. Experiments using a cJun N-terminal kinase (JNK)-deficient cell and an IRS1 JNK-binding mutant showed that JNK is not required for Ser731 phosphorylation. A two-week treatment of obese mice with SA resulted in decreased Ser731 phosphorylation and enhanced insulin signaling. These results suggest that SA enhances insulin signaling by inhibiting Ser731 phosphorylation of IRS1.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.395-402
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• 2009

Insulin appears to play a role in brain physiology, and disturbances of cerebral insulin signalling and glucose homeostasis are implicated in brain pathology. The objective of the present study was to investigate the protective effects of insulin under conditions of oxidative stress induced by hydrogen peroxide ($H_2O_2$) in C6 glial cells. Insulin at concentration of $10^{-7}$ M could prevent 12 h $H_2O_2$-induced cell death. The formation of reactive oxygen species (ROS), nitric oxide (NO) and 2-thiobarbituric acid-reactive substances (TBARS) were significantly scavenged by insulin pre-treatment in C6 glial cells after $H_2O_2$-induced oxidative stress. Insulin significantly stimulated the phosphorylation of Akt in the cells and the activation of Akt was maintained in response to insulin under $H_2O_2$ incubation for 12 h. In conclusion, these results provide evidence that insulin acts as a free radical scavenger and stimulating Akt activity. These data suggest that insulin may be effective in degenerative diseases with oxidative stress.