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Sample records for insulin levels remained

  1. Flaxseed oil supplementation manipulates correlations between serum individual mol % free fatty acid levels and insulin resistance in type 2 diabetics. Insulin resistance and percent remaining pancreatic β-cell function are unaffected.

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    Barre, D E; Mizier-Barre, K A; Griscti, O; Hafez, K

    2016-10-01

    Elevated total serum free fatty acids (FFAs) concentrations have been suggested, controversially, to enhance insulin resistance and decrease percent remaining β-cell function. However, concentrations of individual serum FFAs have never been published in terms of their relationship (correlation) to homeostatic model assessment-insulin resistance (HOMA-IR) and percent remaining β-cell function (HOMA-%β) in the type 2 diabetics (T2Ds). Alpha-linolenic acid consumption has a negative correlation with the insulin resistance, which in turn is negatively correlated with the remaining β-cell function. The primary objective was to test the hypothesis that there would be different relationship (correlation) between the blood serum individual free FFA mol % levels and HOMA-IR and/or HOMA-%β in T2D. The secondary objective was to test the hypothesis that flaxseed oil, previously being shown to be ineffective in the glycemic control in T2Ds, may alter these correlations in a statistically significant manner as well as HOMA-IR and/or HOMA-%β. Patients were recruited via a newspaper advertisement and two physicians have been employed. All the patients came to visit one and three months later for a second visit. At the second visit, the subjects were randomly assigned (double blind) to flaxseed or safflower oil treatment for three months, until the third visit. Different statistically significant correlations or trends towards among some serum individual free FFA mol % levels and HOMA-IR and HOMA-%β, pre- and post-flaxseed and safflower oil supplementation were found. However, flaxseed oil had no impact on HOMA-IR or HOMA-%β despite statistically significant alterations in correlations compared to baseline HOMA-IR. The obtained data indicate that high doses of flaxseed oil have no statistically significant effect on HOMA-IR or HOMA-%β in T2Ds, probably due to the additive effects of negative and positive correlations.

  2. Plasma resistin, adiponectin and leptin levels in relation to insulin resistance

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    Shousha, M.A.; Soliman, S.E.T.

    2010-01-01

    Adipose tissue regulates insulin sensitivity via the circulating adipo cytokines, adiponectin, resistin and leptin. The objective of this study was to compare the levels of resistin, adiponectin and leptin in lean and obese subjects and determine the relationship between circulating adipocytokines and insulin resistance. We examined plasma levels of resistin, adiponectin and leptin in 20 lean subjects with mean body mass index (BMI) of 24, and, 36 nondiabetic obese individuals with mean BMI 34. Insulin resistance was assessed using the homeostasis model assessment ratio (HOMA-R) formula derived from fasting insulin and glucose levels. Resistin levels were not significantly different between the two groups but were significantly higher in women compared with men, 30.4±6.5 vs. 14.4±2.9 mg/l, P<0.01. Resistin did not correlate with BMI but did significantly correlate with HOMA-R, P < 0.01, and this correlation remained significant after adjustment for gender and BMI. Adiponectin levels were significantly reduced in obese compared with lean subjects, P < 0.005 and higher in women, P< 0.001. Adiponectin levels showed significant correlation with HOMA-R and this correlation remained significant after adjustment for gender and BMI. Leptin levels were significantly higher in obese subjects and women and correlated with resistin, but, didn't correlate with HOMA-R. In this small group of patients we demonstrated that insulin resistance correlated most strongly and reciprocally with adiponectin levels. Significant correlation between resistin levels and insulin resistance was also observed. Although a similar trend was apparent for leptin, the correlation with insulin resistance did not achieve statistical significance

  3. Bilirubin Increases Insulin Sensitivity by Regulating Cholesterol Metabolism, Adipokines and PPARγ Levels

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    Liu, Jinfeng; Dong, Huansheng; Zhang, Yong; Cao, Mingjun; Song, Lili; Pan, Qingjie; Bulmer, Andrew; Adams, David B.; Dong, Xiao; Wang, Hongjun

    2015-01-01

    Obesity can cause insulin resistance and type 2 diabetes. Moderate elevations in bilirubin levels have anti-diabetic effects. This study is aimed at determining the mechanisms by which bilirubin treatment reduces obesity and insulin resistance in a diet-induced obesity (DIO) mouse model. DIO mice were treated with bilirubin or vehicle for 14 days. Body weights, plasma glucose, and insulin tolerance tests were performed prior to, immediately, and 7 weeks post-treatment. Serum lipid, leptin, adiponectin, insulin, total and direct bilirubin levels were measured. Expression of factors involved in adipose metabolism including sterol regulatory element-binding protein (SREBP-1), insulin receptor (IR), and PPARγ in liver were measured by RT-PCR and Western blot. Compared to controls, bilirubin-treated mice exhibited reductions in body weight, blood glucose levels, total cholesterol (TC), leptin, total and direct bilirubin, and increases in adiponectin and expression of SREBP-1, IR, and PPARγ mRNA. The improved metabolic control achieved by bilirubin-treated mice was persistent: at two months after treatment termination, bilirubin-treated DIO mice remained insulin sensitive with lower leptin and higher adiponectin levels, together with increased PPARγ expression. These results indicate that bilirubin regulates cholesterol metabolism, adipokines and PPARγ levels, which likely contribute to increased insulin sensitivity and glucose tolerance in DIO mice. PMID:26017184

  4. Circulating docosahexaenoic acid levels are associated with fetal insulin sensitivity.

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    Jin-Ping Zhao

    Full Text Available Arachidonic acid (AA; C20∶4 n-6 and docosahexaenoic acid (DHA; C22∶6 n-3 are important long-chain polyunsaturated fatty acids (LC-PUFA in maintaining pancreatic beta-cell structure and function. Newborns of gestational diabetic mothers are more susceptible to the development of type 2 diabetes in adulthood. It is not known whether low circulating AA or DHA is involved in perinatally "programming" this susceptibility. This study aimed to assess whether circulating concentrations of AA, DHA and other fatty acids are associated with fetal insulin sensitivity or beta-cell function, and whether low circulating concentrations of AA or DHA are involved in compromised fetal insulin sensitivity in gestational diabetic pregnancies.In a prospective singleton pregnancy cohort, maternal (32-35 weeks gestation and cord plasma fatty acids were assessed in relation to surrogate indicators of fetal insulin sensitivity (cord plasma glucose-to-insulin ratio, proinsulin concentration and beta-cell function (proinsulin-to-insulin ratio in 108 mother-newborn pairs. Cord plasma DHA levels (in percentage of total fatty acids were lower comparing newborns of gestational diabetic (n = 24 vs. non-diabetic pregnancies (2.9% vs. 3.5%, P = 0.01. Adjusting for gestational age at blood sampling, lower cord plasma DHA levels were associated with lower fetal insulin sensitivity (lower glucose-to-insulin ratio, r = 0.20, P = 0.036; higher proinsulin concentration, r = -0.37, P <0.0001. The associations remained after adjustment for maternal and newborn characteristics. Cord plasma saturated fatty acids C18∶0 and C20∶0 were negatively correlated with fetal insulin sensitivity, but their levels were not different between gestational diabetic and non-diabetic pregnancies. Cord plasma AA levels were not correlated with fetal insulin sensitivity.Low circulating DHA levels are associated with compromised fetal insulin sensitivity, and may be involved in

  5. Decreased insulin clearance in individuals with elevated 1-h post-load plasma glucose levels.

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    Maria Adelaide Marini

    Full Text Available Reduced insulin clearance has been shown to predict the development of type 2 diabetes. Recently, it has been suggested that plasma glucose concentrations ≥ 8.6 mmol/l (155 mg/dl at 1 h during an oral glucose tolerance test (OGTT can identify individuals at high risk for type 2 diabetes among those who have normal glucose tolerance (NGT 1 h-high. The aim of this study was to examine whether NGT 1 h-high have a decrease in insulin clearance, as compared with NGT individuals with 1-h post-load glucose <8.6 mmol/l (l (155 mg/dl, NGT 1 h-low. To this end, 438 non-diabetic White individuals were subjected to OGTT and euglycemic-hyperinsulinemic clamp to evaluate insulin clearance and insulin sensitivity. As compared with NGT 1 h-low individuals, NGT 1 h-high had significantly higher 1-h and 2-h post-load plasma glucose and 2-h insulin levels as well as higher fasting glucose and insulin levels. NGT 1 h-high exhibited also a significant decrease in both insulin sensitivity (P<0.0001 and insulin clearance (P = 0.006 after adjusting for age, gender, adiposity measures, and insulin sensitivity. The differences in insulin clearance remained significant after adjustment for fasting glucose (P = 0.02 in addition to gender, age, and BMI. In univariate analyses adjusted for gender and age, insulin clearance was inversely correlated with body weight, body mass index, waist, fat mass, 1-h and 2-h post-load glucose levels, fasting, 1-h and 2-h post-load insulin levels, and insulin-stimulated glucose disposal. In conclusion, our data show that NGT 1 h-high have a reduction in insulin clearance as compared with NGT 1 h-low individuals; this suggests that impaired insulin clearance may contribute to sustained fasting and post-meal hyperinsulinemia.

  6. Plasma kisspeptin levels are associated with insulin secretion in nondiabetic individuals.

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    Francesco Andreozzi

    Full Text Available To evaluate if plasma kisspeptin concentrations are associated with insulin secretion, as suggested by recent in vitro studies, independently of confounders. 261 nondiabetic subjects were stratified into tertiles according to kisspeptin values. Insulin secretion was assessed using indexes derived from oral glucose tolerance test (OGTT. After adjusting for age, gender, and BMI, subjects in the highest (tertile 3 kisspeptin group exhibited significantly lower values of insulinogenic index, corrected insulin response (CIR30, and Stumvoll indexes for first-phase and second-phase insulin release as compared with low (tertile 1 or intermediate (tertile 2 kisspeptin groups. Univariate correlations between kisspeptin concentration and metabolic variables showed that kisspeptin concentration was significantly and positively correlated with age, blood pressure, and 2-h post-load glucose, and inversely correlated with BMI, and waist circumference. There was an inverse relationship between kisspeptin levels and OGTT-derived indexes of glucose-stimulated insulin secretion. A multivariable regression analysis in a model including all the variables significantly correlated with kisspeptin concentration showed thar age (β = -0.338, P<0.0001, BMI (β = 0.272, P<0.0001, 2-h post-load glucose (β = -0.229, P<0.0001, and kisspeptin (β = -0.105, P = 0.03 remained associated with insulinogenic index. These factors explained 34.6% of the variance of the insulinogenic index. In conclusion, kisspeptin concentrations are associated with insulin secretion independently of important determinants of glucose homeostasis such as gender, age, adiposity, 2-h post-load glucose, and insulin sensitivity.

  7. Serum liver fatty acid binding protein levels correlate positively with obesity and insulin resistance in Chinese young adults.

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    Juan Shi

    Full Text Available BACKGROUND: Liver fatty acid-binding protein (FABP1 plays an inconclusive role in adiposity. We investigated the association of serum FABP1 levels with obesity and insulin resistance in Chinese young people under 30 years old. METHODOLOGY AND PRINCIPAL FINDINGS: Cross-sectional analysis including 200 obese and 172 normal-weight subjects matched for age and sex, anthropometric measurements were performed and serum FABP1 and biochemical characteristics were measured. Insulin resistance was determined by homeostasis model assessment of insulin resistance (HOMA-IR and by the insulin sensitivity index (S(i derived from Bergman's minimal model. FABP1 levels in obese subjects were significantly higher than those in normal-weight subjects (p<0.001 and the significance remained after adjustment for age, gender, alanine and aspartate aminotransferases (p<0.001. Serum FABP1 levels were significantly correlated with many metabolic-related parameters, with BMI and triglycerides as the independent determinants. FABP1 levels remained an independent risk factor of insulin resistance assessed by binary S(i (OR = 1.868 per SD unit, 95% CI [1.035-3.373], p = 0.038 after adjustment for age, sex, BMI, waist circumference, systolic blood pressure, serum triacylglycerol, total cholesterol, HDL- and LDL-cholesterol,. FABP1 levels were also elevated with an increasing number of components of the metabolic syndrome (p for trend <0.001. Multiple regression modeling for the MetS and its components demonstrated that hypertriglyceridemia and low HDL-cholesterol were significantly correlated to serum FABP1 levels. CONCLUSIONS AND SIGNIFICANCE: Serum FABP1 correlates positively with obesity and insulin resistance in Chinese young adults. Our data supports the fact that FABP1 might be an important mediator participating in fatty acid metabolism and energy balance.

  8. Synthesis of cytochrome c oxidase 1 (SCO1) inhibits insulin sensitivity by decreasing copper levels in adipocytes.

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    Wei, Xiang-Bo; Guo, Liang; Liu, Yang; Zhou, Shui-Rong; Liu, Yuan; Dou, Xin; Du, Shao-Yue; Ding, Meng; Peng, Wan-Qiu; Qian, Shu-Wen; Huang, Hai-Yan; Tang, Qi-Qun

    2017-09-23

    Dysregulation of insulin signaling leads to type 2 diabetes mellitus (T2DM) and other metabolic disorders. Obesity is an important contributor to insulin resistance, and although the understanding of this relationship has improved in recent years, the mechanism of obesity-induced insulin resistance is not completely understood. Disorders of copper metabolism tend to accompany the development of obesity, which increases the risk of insulin resistance. Synthesis of cytochrome c oxidase 1 (SCO1) functions in the assembly of cytochrome c oxidase (COX) and cellular copper homeostasis. However, the role of SCO1 in the regulation of metabolism remains unknown. Here, we found that obese mice had higher expression of SCO1 and lower levels of copper in white adipose tissue (WAT) than did the control mice. Overexpression of SCO1 in adipocytes was associated with copper deficiency. Copper increased insulin sensitivity by decreasing the level of phosphatase and tensin homolog (PTEN) protein. Ectopic expression of SCO1 led to insulin resistance and was accompanied by a decrease in intracellular copper level, and addition of copper abolished the inhibitory effect of SCO1 on insulin sensitivity. Our results demonstrated a novel role of SCO1 in modulating insulin sensitivity via the regulation of copper concentration in WAT and suggested a potential therapeutic target for T2DM. Copyright © 2017. Published by Elsevier Inc.

  9. The Relationship between 25-hydroxyvitamin D Levels, Insulin Sensitivity and Insulin Secretion in Women 3 Years after Delivery.

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    Tänczer, Tímea; Magenheim, Rita; Fürst, Ágnes; Domján, Beatrix; Janicsek, Zsófia; Szabó, Eszter; Ferencz, Viktória; Tabák, Ádám G

    2017-12-01

    There is a direct correlation between 25-hydroxyvitamin D (25[OH]D) levels and insulin sensitivity. Furthermore, women with gestational diabetes (GDM) may have lower levels of 25(OH)D compared to controls. The present study intended to investigate 25(OH)D levels and their association with insulin sensitivity and insulin secretion in women with prior GDM and in controls 3.2 years after delivery. A total of 87 patients with prior GDM and 45 randomly selected controls (age range, 22 to 44 years) with normal glucose tolerance during pregnancy nested within a cohort of all deliveries at Saint Margit Hospital, Budapest, between January 1 2005, and December 31 2006, were examined. Their 25(OH) D levels were measured by radioimmunoassay. Insulin sensitivity and fasting insulin secretion were estimated using the homeostasis model asssessment (HOMA) calculator and early insulin secretion by the insulinogenic index based on a 75 g oral glucose tolerance test. There was no significant difference in 25(OH)D levels between cases and controls (27.2±13.1 [±SD] vs. 26.9±9.8 ng/L). There was a positive association between HOMA insulin sensitivity and 25(OH)D levels (beta = 0.017; 95% CI 0.001 to 0.034/1 ng/mL) that was robust to adjustment for age and body mass index. There was a nonsignificant association between HOMA insulin secretion and 25(OH)D (p=0.099), while no association was found with the insulinogenic index. Prior GDM status was not associated with 25(OH)D levels; however, 25(OH) D levels were associated with HOMA insulin sensitivity. It is hypothesized that the association between HOMA insulin secretion and 25(OH)D levels is related to the autoregulation of fasting glucose levels because no association between 25(OH)D and insulinogenic index was found. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

  10. Association between omentin levels and insulin resistance in pregnancy.

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    Aktas, G; Alcelik, A; Ozlu, T; Tosun, M; Tekce, B K; Savli, H; Tekce, H; Dikbas, O

    2014-03-01

    Omentin is a new adipokine secreted mainly from visceral adipose tissue. Serum omentin is found to be reduced in patients with impaired glucose tolerance, type 2 diabetes mellitus, obesity and insulin resistant states. Despite the fact that pregnancy is also characterized with hyperinsulinemia, literature is lacking about data of omentin levels and its association with insulin resistance in pregnant women. We aimed to evaluate the association of omentin levels and insulin resistance in pregnant women and to compare these levels with those of non-pregnant, non-diabetic women. Uncomplicated pregnant women who admit to our outpatient clinics for routine follow-up were included in the study group. Non-pregnant women without diabetes mellitus were served as control group. Fasting glucose, insulin, omentin levels and HOMA IR were recorded. SPSS 15.0 for Windows was used for statistical analysis. There were 36 pregnant women in the study group and 37 healthy, non-pregnant women in the control group. Serum omentin and fasting glucose levels were significantly decreased and fasting insulin was significantly increased in the study group compared to control group. Omentin might be an indicator of insulin resistance in pregnant women. Larger prospective studies are needed to claim whether omentin can have a clinical use for diagnosis of gestational diabetes mellitus. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  11. Changes in insulin and insulin signaling in Alzheimer’s disease: cause or consequence?

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    Stanley, Molly; Macauley, Shannon L.

    2016-01-01

    Individuals with type 2 diabetes have an increased risk for developing Alzheimer’s disease (AD), although the causal relationship remains poorly understood. Alterations in insulin signaling (IS) are reported in the AD brain. Moreover, oligomers/fibrils of amyloid-β (Aβ) can lead to neuronal insulin resistance and intranasal insulin is being explored as a potential therapy for AD. Conversely, elevated insulin levels (ins) are found in AD patients and high insulin has been reported to increase Aβ levels and tau phosphorylation, which could exacerbate AD pathology. Herein, we explore whether changes in ins and IS are a cause or consequence of AD. PMID:27432942

  12. 2-deoxyglucose tissue levels and insulin levels following tolazamide dosing in normal and obese mice

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    Skillman, C.A.; Fletcher, H.P.

    1986-01-01

    The effect of tolazamide (TZ), a sulfonylurea, on 14 C-2-deoxyglucose ( 14 C-2DG) tissue distribution and insulin levels of normal and obese mice was investigated using an in vivo physiological method. Acute doses of TZ (50 mg/kg ip) increased 14 C-2DG levels in gastrocnemius muscle and retroperitoneal fat and produced a transient elevation of insulin which most likely accounts for the increased 14 C-2DG levels in muscle and fat. The results demonstrate that the in vivo 14 C-2DG method produced results consistent with known actions of sulfonylureas on in vitro hexose assimilation in muscle and fat. Subchronic treatment (7 days) with TZ 50 mg/kg ip twice daily did not result in increased insulin-stimulated 14 C-2DG tissue levels in normal mice when compared to saline treated controls. However, insulin levels were lower in mice treated subchronically with TZ compared to saline controls suggesting an enhancement of insulin action. Viable yellow obese mice represent a model of maturity onset obesity presenting with insulin resistance. The insulin resistance of this obese strain appears to reside in the fat tissue as assessed by comparing 14 C-2DG tissue levels of obese mice with lean littermate controls. Subchronic TZ treatment had no effect on 14 C-2DG uptake in fat or muscle tissue of viable yellow obese mice and did not alter their plasma insulin levels. It appears that genetically obese viable mice may be resistant to subchronic treatment with TZ. (author)

  13. Genetic evidence of a causal effect of insulin resistance on branched-chain amino acid levels.

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    Mahendran, Yuvaraj; Jonsson, Anna; Have, Christian T; Allin, Kristine H; Witte, Daniel R; Jørgensen, Marit E; Grarup, Niels; Pedersen, Oluf; Kilpeläinen, Tuomas O; Hansen, Torben

    2017-05-01

    Fasting plasma levels of branched-chain amino acids (BCAAs) are associated with insulin resistance, but it remains unclear whether there is a causal relation between the two. We aimed to disentangle the causal relations by performing a Mendelian randomisation study using genetic variants associated with circulating BCAA levels and insulin resistance as instrumental variables. We measured circulating BCAA levels in blood plasma by NMR spectroscopy in 1,321 individuals from the ADDITION-PRO cohort. We complemented our analyses by using previously published genome-wide association study (GWAS) results from the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) (n = 46,186) and from a GWAS of serum BCAA levels (n = 24,925). We used a genetic risk score (GRS), calculated using ten established fasting serum insulin associated variants, as an instrumental variable for insulin resistance. A GRS of three variants increasing circulating BCAA levels was used as an instrumental variable for circulating BCAA levels. Fasting plasma BCAA levels were associated with higher HOMA-IR in ADDITION-PRO (β 0.137 [95% CI 0.08, 0.19] p = 6 × 10 -7 ). However, the GRS for circulating BCAA levels was not associated with fasting insulin levels or HOMA-IR in ADDITION-PRO (β -0.011 [95% CI -0.053, 0.032] p = 0.6 and β -0.011 [95% CI -0.054, 0.031] p = 0.6, respectively) or in GWAS results for HOMA-IR from MAGIC (β for valine-increasing GRS -0.012 [95% CI -0.069, 0.045] p = 0.7). By contrast, the insulin-resistance-increasing GRS was significantly associated with increased BCAA levels in ADDITION-PRO (β 0.027 [95% CI 0.005, 0.048] p = 0.01) and in GWAS results for serum BCAA levels (β 1.22 [95% CI 0.71, 1.73] p = 4 × 10 -6 , β 0.96 [95% CI 0.45, 1.47] p = 3 × 10 -4 , and β 0.67 [95% CI 0.16, 1.18] p = 0.01 for isoleucine, leucine and valine levels, respectively) and instrumental variable analyses in ADDITION

  14. Efficacy of 2-hour post glucose insulin levels in predicting insulin resistance in polycystic ovarian syndrome with infertility

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    Pikee Saxena

    2011-01-01

    Full Text Available Background : Insulin resistance (IR is central to the pathogenesis of polycystic ovarian syndrome (PCOS, but tests for determining IR are elaborate, tedious and expensive. Aims : To evaluate if "2-hour post-glucose insulin level" is an effective indicator of IR and can aid in diagnosing IR in infertile PCOS women. Settings and Design : Observational study at infertility clinic of a tertiary care center. Materials and Methods : 50 infertile women with PCOS and 20 females with tubal/male factor infertility were evaluated for the presence of IR, as defined by the fasting/2-hour post-glucose insulin levels cutoffs of >25/>41 μU/mL, respectively. The clinical, metabolic and endocrinologic profile was determined in both the groups. Statistical Analysis : Statistical analysis was performed using SPSS (Chicago, IL, USA. Results : Body mass index, post load glucose, insulin, glucose/insulin ratio, area under curve (AUC of glucose and insulin and insulinogenic index were significantly lower in the controls as compared to the PCOS group. "2-hour post-glucose insulin levels" were elevated in 88% of PCOS individuals but were normal in all females not suffering from PCOS. These levels significantly correlated with AUC of glucose and insulin, and insulinogenic index and inversely correlated with 2-hour glucose to insulin ratio (r=0.827, 0.749 and −0.732, respectively. Conclusions : "2-hour post-glucose insulin levels" appears to be a good indicator of IR. It can be a useful tool, especially in low resource setting where a single sample can confirm the diagnosis, thus reducing cost and repeat visits.

  15. Tyrosine levels are associated with insulin resistance in patients with nonalcoholic fatty liver disease

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    Kawanaka, Miwa; Nishino, Ken; Oka, Takahito; Urata, Noriyo; Nakamura, Jun; Suehiro, Mitsuhiko; Kawamoto, Hirofumi; Chiba, Yasutaka; Yamada, Gotaro

    2015-01-01

    Objective Amino acid imbalance is often found in patients with cirrhosis, and this imbalance is associated with insulin resistance. However, the mechanism underlying the relationship between amino acid imbalance and insulin resistance remains unclear. We evaluated serum amino acid concentrations in patients with nonalcoholic fatty liver disease to determine if any of the levels of amino acids were associated with the biochemical markers and fibrosis stage of nonalcoholic steatohepatitis (NASH). Methods In 137 patients with nonalcoholic fatty liver disease who underwent liver biopsy, plasma levels of branched-chain amino acid (BCAA), tyrosine (Tyr), and the BCAA-to-Tyr ratio values were determined using mass spectroscopy. These values were then assessed for associations with fibrosis stage, anthropometric markers (age, sex, and body mass index), biochemical markers (alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, albumin, platelet count, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and glycosylated hemoglobin), and relevant disease-specific biomarkers (homeostasis model assessment of insulin resistance [HOMA-IR], serum iron, ferritin, leptin, adiponectin, high-sensitivity C-reactive protein, and hyaluronic acid). Results Serum albumin levels, plasma BCAA levels, and BCAA-to-Tyr ratio values were negatively associated with the fibrosis stage. In contrast, Tyr levels increased with increasing fibrotic staging. Tyr levels were also correlated with HOMA-IR results. Conclusion Plasma BCAA levels in patients with NASH decreased with increasing liver fibrosis, while Tyr levels increased with increasing fibrotic stage. These results suggest that amino acid imbalance and insulin resistance are intimately involved in a complex pathogenic mechanism for NASH. PMID:26082668

  16. Aspartame in conjunction with carbohydrate reduces insulin levels during endurance exercise

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    Siegler Jason

    2012-08-01

    Full Text Available Abstract Background As most sport drinks contain some form of non-nutritive sweetener (e.g. aspartame, and with the variation in blood glucose regulation and insulin secretion reportedly associated with aspartame, a further understanding of the effects on insulin and blood glucose regulation during exercise is warranted. Therefore, the aim of this preliminary study was to profile the insulin and blood glucose responses in healthy individuals after aspartame and carbohydrate ingestion during rest and exercise. Findings Each participant completed four trials under the same conditions (45 min rest + 60 min self-paced intense exercise differing only in their fluid intake: 1 carbohydrate (2% maltodextrin and 5% sucrose (C; 2 0.04% aspartame with 2% maltodextrin and 5% sucrose (CA; 3 water (W; and 4 aspartame (0.04% aspartame with 2% maltodextrin (A. Insulin levels dropped significantly for CA versus C alone (43% between pre-exercise and 30 min, while W and A insulin levels did not differ between these time points. Conclusions Aspartame with carbohydrate significantly lowered insulin levels during exercise versus carbohydrate alone.

  17. Effect of thiazolidinedione treatment on resistin levels in insulin resistant sprague dawley rats

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    Yousaf, I.; Hameed, W.; Rajput, T.A.

    2015-01-01

    Insulin resistance is manifested by decreased effect of fixed quantity of insulin on glucose metabolism leading to type 2 diabetes mellitus. Visceral obesity has been positively correlated with insulin resistance but its mechanism is not fully defined. Insulin resistance may be the consequence of adipocytokines including visfatin and resistin. This study was designed to see the effect of thiazolidinediones on levels of resistin in insulin resistant rats. Methods: Ninety Sprague Dawley rats were randomly divided into three groups. Group I served as control. Rats in Group II and III were made insulin resistant diabetics. Group III was treated with rosiglitazone after development of diabetes. Plasma glucose, serum triglycerides, HDL, TG:HDL ratio and serum resistin levels were analysed. Results: Body weight and plasma glucose were significantly increased (p<0.05) along with TG:HDL ratio (p<0.05) in group II and group III at the end of 4th week. Serum resistin levels also increased significantly (p<0.05) in group II and III at the end of 4th week. Treatment of group III with rosiglitazone led to improvement in insulin resistance with decrease in serum resistin levels (p<0.05). Conclusion: Increased serum resistin level indicates insulin resistance and impending hyperglycaemia. Thiazolidinediones augment sensitivity of insulin to restore normoglycaemia by decreasing serum resistin level. (author)

  18. Effects of inhibition of interleukin-6 signalling on insulin sensitivity and lipoprotein (a levels in human subjects with rheumatoid diseases.

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    Olaf Schultz

    2010-12-01

    Full Text Available Interleukin-6 (IL-6 is a pro-inflammatory cytokine that has been found to be increased in type 2 diabetic subjects. However, it still remains unclear if these elevated IL-6 levels are co-incidental or if this cytokine is causally related to the development of insulin resistance and type 2 diabetes in humans. Therefore, in the present study we examined insulin sensitivity, serum adipokine levels and lipid parameters in human subjects before and after treatment with the IL-6 receptor antibody Tocilizumab.11 non-diabetic patients with rheumatoid disease were included in the study. HOMA-IR was calculated and serum levels for leptin, adiponectin, triglycerides, LDL-cholesterol, HDL-cholesterol and lipoprotein (a (Lp (a were measured before as well as one and three months after Tocilizumab treatment. The HOMA index for insulin resistance decreased significantly. While leptin concentrations were not altered by inhibition of IL-6 signalling, adiponectin concentrations significantly increased. Thus the leptin to adiponectin ratio, a novel marker for insulin resistance, exhibited a significant decrease. Serum triglycerides, LDL-cholesterol and HDL-cholesterol tended to be increased whereas Lp (a levels significantly decreased.Inhibition of IL-6 signalling improves insulin sensitivity in humans with immunological disease suggesting that elevated IL-6 levels in type 2 diabetic subjects might be causally involved in the pathogenesis of insulin resistance. Furthermore, our data indicate that inhibition of IL-6 signalling decreases Lp (a serum levels, which might reduce the cardiovascular risk of human subjects.

  19. Implication of low level inflammation in the insulin resistance of adipose tissue at late pregnancy.

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    de Castro, J; Sevillano, J; Marciniak, J; Rodriguez, R; González-Martín, C; Viana, M; Eun-suk, O H; de Mouzon, S Hauguel; Herrera, E; Ramos, M P

    2011-11-01

    Insulin resistance is a characteristic of late pregnancy, and adipose tissue is one of the tissues that most actively contributes to the reduced maternal insulin sensitivity. There is evidence that pregnancy is a condition of moderate inflammation, although the physiological role of this low-grade inflammation remains unclear. The present study was designed to validate whether low-grade inflammation plays a role in the development of insulin resistance in adipose tissue during late pregnancy. To this end, we analyzed proinflammatory adipokines and kinases in lumbar adipose tissue of nonpregnant and late pregnant rats at d 18 and 20 of gestation. We found that circulating and tissue levels of adipokines, such as IL-1β, plasminogen activator inhibitor-1, and TNF-α, were increased at late pregnancy, which correlated with insulin resistance. The observed increase in adipokines coincided with an enhanced activation of p38 MAPK in adipose tissue. Treatment of pregnant rats with the p38 MAPK inhibitor SB 202190 increased insulin-stimulated tyrosine phosphorylation of the insulin receptor (IR) and IR substrate-1 in adipose tissue, which was paralleled by a reduction of IR substrate-1 serine phosphorylation and an enhancement of the metabolic actions of insulin. These results indicate that activation of p38 MAPK in adipose tissue contributes to adipose tissue insulin resistance at late pregnancy. Furthermore, the results of the present study support the hypothesis that physiological low-grade inflammation in the maternal organism is relevant to the development of pregnancy-associated insulin resistance.

  20. Brain insulin lowers circulating BCAA levels by inducing hepatic BCAA catabolism

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    Shin, Andrew C.; Fasshauer, Martin; Filatova, Nika; Grundell, Linus A.; Zielinski, Elizabeth; Zhou, Jian-Ying; Scherer, Thomas; Lindtner, Claudia; White, Phillip J.; Lapworth, Amanda L.; Ilkayeva, Olga; Knippschild, Uwe; Wolf, Anna M.; Scheja, Ludger; Grove, Kevin L.

    2014-01-01

    Circulating branched-chain amino acid (BCAA) levels are elevated in obesity/diabetes and are a sensitive predictor for type 2 diabetes. Here we show in rats that insulin dose-dependently lowers plasma BCAA levels through induction of hepatic protein expression and activity of branched-chain α keto-acid dehydrogenase (BCKDH), the rate-limiting enzyme in the BCAA degradation pathway. Selective induction of hypothalamic insulin signaling in rats and genetic modulation of brain insulin receptors ...

  1. Differential effects of insulin injections and insulin infusions on levels ...

    African Journals Online (AJOL)

    Studies have shown that while injections of insulin cause an increase in fat mass, infusions of insulin increase fat mass. The aim of this paper was to test the hypothesis that if an increase in glycogen is an indicator of an impending increase in adipose mass, then insulin infusions should not increase glycogen, while insulin ...

  2. Negative association of acetate with visceral adipose tissue and insulin levels

    Directory of Open Access Journals (Sweden)

    Layden BT

    2012-02-01

    Full Text Available Brian T Layden1, Sudha K Yalamanchi1, Thomas MS Wolever2, Andrea Dunaif1, William L Lowe Jr11Division of Endocrinology, Metabolism and Molecular Medicine (BTL, SKY, AD, WLL, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA; 2Department of Nutritional Sciences (TMSW, University of Toronto, Toronto, CanadaBackground: The composition of gut flora has been proposed as a cause of obesity, a major risk factor for type 2 diabetes. The objective of this study was to assess whether serum short chain fatty acids, a major by-product of fermentation in gut flora, are associated with obesity and/or diabetes-related traits (insulin sensitivity and secretion.Methods: The association of serum short chain fatty acids levels with measures of obesity was assessed using body mass index, computerized tomography scan, and dual photon X-ray absorptiometry scan. Insulin sensitivity and insulin secretion were both determined from an oral glucose tolerance test and insulin sensitivity was also determined from a hyperinsulinemic euglycemic clamp.Results: In this population of young, obese women, acetate was negatively associated with visceral adipose tissue determined by computerized tomography scan and dual photon X-ray absorptiometry scan, but not body mass index. The level of the short chain fatty acids acetate, but not propionate or butyrate, was also negatively associated with fasting serum insulin and 2 hour insulin levels in the oral glucose tolerance test.Conclusions: In this population, serum acetate was negatively associated with visceral adipose tissue and insulin levels. Future studies need to verify these findings and expand on these observations in larger cohorts of subjects.Keywords: obesity, insulin, gut flora, short chain fatty acids 

  3. Tyrosine levels are associated with insulin resistance in patients with nonalcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    Kawanaka M

    2015-06-01

    Full Text Available Miwa Kawanaka,1 Ken Nishino,1 Takahito Oka,1 Noriyo Urata,1 Jun Nakamura,1 Mitsuhiko Suehiro,1 Hirofumi Kawamoto,1 Yasutaka Chiba,2 Gotaro Yamada1 1Department of General Internal Medicine 2, Kawasaki Hospital, Kawasaki Medical School, Okayama, Japan; 2Clinical Research Center, Kinki University Hospital, Sayama, Japan Objective: Amino acid imbalance is often found in patients with cirrhosis, and this imbalance is associated with insulin resistance. However, the mechanism underlying the relationship between amino acid imbalance and insulin resistance remains unclear. We evaluated serum amino acid concentrations in patients with nonalcoholic fatty liver disease to determine if any of the levels of amino acids were associated with the biochemical markers and fibrosis stage of nonalcoholic steatohepatitis (NASH. Methods: In 137 patients with nonalcoholic fatty liver disease who underwent liver biopsy, plasma levels of branched-chain amino acid (BCAA, tyrosine (Tyr, and the BCAA-to-Tyr ratio values were determined using mass spectroscopy. These values were then assessed for associations with fibrosis stage, anthropometric markers (age, sex, and body mass index, biochemical markers (alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, albumin, platelet count, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and glycosylated hemoglobin, and relevant disease-specific biomarkers (homeostasis model assessment of insulin resistance [HOMA-IR], serum iron, ferritin, leptin, adiponectin, high-sensitivity C-reactive protein, and hyaluronic acid. Results: Serum albumin levels, plasma BCAA levels, and BCAA-to-Tyr ratio values were negatively associated with the fibrosis stage. In contrast, Tyr levels increased with increasing fibrotic staging. Tyr levels were also correlated with HOMA-IR results. Conclusion: Plasma BCAA levels in patients with NASH decreased with increasing liver fibrosis, while Tyr levels

  4. Changes of serum leptin, adiponection and insulin levels in females with simple obesity

    International Nuclear Information System (INIS)

    Wei Tao; Duan Wennuo; Ma Yongxiu; Chen Yanping

    2004-01-01

    Objective: To study the changes of serum leptin, insulin and adiponectin levels and their relationship with BMI in females with simple obesity. Methods: Serum leptin, adiponectin and insulin levels were measured with RIA in 48 pre-obese females (BMI=23-24.9 kg/m 2 ), 40 females with simple obesity, (BMI≥25 kg/m 2 ) and 42 female controls (BMI 18-22.9 kg/m 2 ). Correlations among these variables were studied. Results: Serum leptin, insulin levels were significantly higher and serum adiponectin levels were significantly lower in both the pre-obese and obese females than those in controls. Serum leptin, insulin levels were positively correlated to BMI; Serum adiponectin levels were negatively correlated to BMI. Conclusion: Within normal range of BMI, the leptin-insulin feedback mechanism provided satisfactory self-regulation. However, with excessive BMI, this dynamic equilibrium would be disrupted. The defective equilibrium, together with the abnormal low adiponectin level, would predispose to the development of diabetes mellitus. (authors)

  5. The changes in levels of C-P and insulin in glucose tolerance test in rats with experimental non-insulin dependent diabetes mellitus

    International Nuclear Information System (INIS)

    Liu Xinqiu; Lei Ming

    2001-01-01

    The changes in levels of C-P and insulin were investigated in the GT test in rats with non-insulin dependent diabetes mellitus. In order to establish a model of non-insulin dependent diabetes mellitus (NIDDM), the authors injected rats with small dose streptozocoi (i.v.). Two weeks after the injection, the rats developed impaired glucose tolerance (IGT). Then, they were fed with high energy diet for eight weeks to form NIDDM. The results showed that the highest peak time of C-P and insulin in NIDDM was remarkably later than that in normal subjects, the highest peak time was in two hours (P < 0.05). The data suggest that level of C-P could accurately respond to level of insulin, and this experimental non-insulin dependent diabetes mellitus model is ideal

  6. Elevated fasting insulin levels increase the risk of abdominal obesity in Korean men.

    Science.gov (United States)

    Park, Sung Keun; Oh, Chang-Mo; Jung, Taegi; Choi, Young-Jun; Chung, Ju Youn; Ryoo, Jae-Hong

    2017-04-01

    This study was designed to investigate whether an elevated fasting insulin level predicts abdominal obesity. A cohort study was conducted with 13,707 non-obese Korean men. They were categorized into 4 groups according to the quartile of fasting insulin level, and followed up from 2005 to 2010. Incidence rates of obesity were compared among the 4 groups during follow-up, and a Cox proportional hazards model was used to calculate hazard ratios (HRs) for abdominal obesity according to fasting insulin level. The overall incidence rate of obesity was 16.2%, but the rate increased in proportion to the fasting insulin level (quartiles 1-4: 9.8%, 12.4%, 16.9%, 25.5%, Pobesity increased proportionally to baseline fasting insulin level in an unadjusted model. However, after adjustment for covariates, including baseline waist circumference (WC), only in the quartile 4 group was the statistical significance of the association maintained [quartile 2-4; abdominal obesity: 0.89 (0.76-1.02), 1.00 (0.86-1.14) and 1.24 (1.08-1.43), P for trend obesity was highest in the group with the highest fasting insulin levels, an overall proportional relationship between fasting insulin level and incident abdominal obesity was not found. Additionally, this association was largely accounted for by baseline WC. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Differential interaction of Apolipoprotein-E isoforms with insulin receptors modulates brain insulin signaling in mutant human amyloid precursor protein transgenic mice.

    Science.gov (United States)

    Chan, Elizabeth S; Chen, Christopher; Cole, Gregory M; Wong, Boon-Seng

    2015-09-08

    It is unclear how human apolipoprotein E4 (ApoE4) increases the risk for Alzheimer's disease (AD). Although Aβ levels can lead to insulin signaling impairment, these experiments were done in the absence of human ApoE. To examine ApoE role, we crossed the human ApoE-targeted replacement mice with mutant human amyloid precursor protein (APP) mice. In 26 week old mice with lower Aβ levels, the expression and phosphorylation of insulin signaling proteins remained comparable among APP, ApoE3xAPP and ApoE4xAPP mouse brains. When the mice aged to 78 weeks, these proteins were markedly reduced in APP and ApoE4xAPP mouse brains. While Aβ can bind to insulin receptor, how ApoE isoforms modulate this interaction remains unknown. Here, we showed that ApoE3 had greater association with insulin receptor as compared to ApoE4, regardless of Aβ42 concentration. In contrast, ApoE4 bound more Aβ42 with increasing peptide levels. Using primary hippocampal neurons, we showed that ApoE3 and ApoE4 neurons are equally sensitive to physiological levels of insulin. However, in the presence of Aβ42, insulin failed to elicit a downstream response only in ApoE4 hippocampal neurons. Taken together, our data show that ApoE genotypes can modulate this Aβ-mediated insulin signaling impairment.

  8. Brain insulin lowers circulating BCAA levels by inducing hepatic BCAA catabolism.

    Science.gov (United States)

    Shin, Andrew C; Fasshauer, Martin; Filatova, Nika; Grundell, Linus A; Zielinski, Elizabeth; Zhou, Jian-Ying; Scherer, Thomas; Lindtner, Claudia; White, Phillip J; Lapworth, Amanda L; Ilkayeva, Olga; Knippschild, Uwe; Wolf, Anna M; Scheja, Ludger; Grove, Kevin L; Smith, Richard D; Qian, Wei-Jun; Lynch, Christopher J; Newgard, Christopher B; Buettner, Christoph

    2014-11-04

    Circulating branched-chain amino acid (BCAA) levels are elevated in obesity/diabetes and are a sensitive predictor for type 2 diabetes. Here we show in rats that insulin dose-dependently lowers plasma BCAA levels through induction of hepatic protein expression and activity of branched-chain α-keto acid dehydrogenase (BCKDH), the rate-limiting enzyme in the BCAA degradation pathway. Selective induction of hypothalamic insulin signaling in rats and genetic modulation of brain insulin receptors in mice demonstrate that brain insulin signaling is a major regulator of BCAA metabolism by inducing hepatic BCKDH. Short-term overfeeding impairs the ability of brain insulin to lower BCAAs in rats. High-fat feeding in nonhuman primates and obesity and/or diabetes in humans is associated with reduced BCKDH protein in liver. These findings support the concept that decreased hepatic BCKDH is a major cause of increased plasma BCAAs and that hypothalamic insulin resistance may account for impaired BCAA metabolism in obesity and diabetes. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Serum Insulin, Glucose, Indices of Insulin Resistance, and Risk of Lung Cancer.

    Science.gov (United States)

    Argirion, Ilona; Weinstein, Stephanie J; Männistö, Satu; Albanes, Demetrius; Mondul, Alison M

    2017-10-01

    Background: Although insulin may increase the risk of some cancers, few studies have examined fasting serum insulin and lung cancer risk. Methods: We examined serum insulin, glucose, and indices of insulin resistance [insulin:glucose molar ratio and homeostasis model assessment of insulin resistance (HOMA-IR)] and lung cancer risk using a case-cohort study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study of Finnish men. A total of 196 cases and 395 subcohort members were included. Insulin and glucose were measured in fasting serum collected 5 to 12 years before diagnosis. Cox proportional hazards models were utilized to estimate the relative risk of lung cancer. Results: The average time between blood collection and lung cancer was 9.6 years. Fasting serum insulin levels were 8.7% higher in subcohort members than cases. After multivariable adjustment, men in the fourth quartile of insulin had a significantly higher risk of lung cancer than those in the first quartile [HR = 2.10; 95% confidence interval (CI), 1.12-3.94]. A similar relationship was seen with HOMA-IR (HR = 1.83; 95% CI, 0.99-3.38). Risk was not strongly associated with glucose or the insulin:glucose molar ratio ( P trend = 0.55 and P trend = 0.27, respectively). Conclusions: Higher fasting serum insulin concentrations, as well as the presence of insulin resistance, appear to be associated with an elevated risk of lung cancer development. Impact: Although insulin is hypothesized to increase risk of some cancers, insulin and lung cancer remain understudied. Higher insulin levels and insulin resistance were associated with increased lung cancer risk. Although smoking cessation is the best method of lung cancer prevention, other lifestyle changes that affect insulin concentrations and sensitivity may reduce lung cancer risk. Cancer Epidemiol Biomarkers Prev; 26(10); 1519-24. ©2017 AACR . ©2017 American Association for Cancer Research.

  10. Ten-year weight gain is associated with elevated fasting insulin levels and precedes glucose elevation.

    Science.gov (United States)

    Pennings, Nicholas; Jaber, Johnny; Ahiawodzi, Peter

    2018-05-01

    Numerous studies have examined the relationship between endogenous insulin and weight change with mixed results. This study examined the relationship between fasting insulin levels, insulin resistance (IR), and 10-year weight change by glycaemic stage. Using data from the US National Health and Nutrition Examination Survey 2011-2014, 3840 participants were divided into 6 groups based on fasting glucose and fasting insulin levels. Fasting insulin concentrations were dichotomized into <25th percentile (normal) and ≥25th percentile (elevated). Ten-year weight change associated with fasting insulin was assessed by glycaemic stage. Average weight change over a 10-year period was higher in individuals with elevated insulin levels compared to the first quartile (1.40 lbs. vs 11.12 lbs, P < .0001). Across all groups, a 1 μU increase in fasting insulin levels resulted in a 0.52-pound increase in weight (P < .0001). Similarly, an increase in HOMA-IR was associated with increase in weight (1.32 lbs per IR unit, P < .0001). Marginal increases in weight were most pronounced in the normal insulin groups compared to elevated insulin groups and diminished as glycaemic stage progressed. Elevated fasting insulin level was positively associated with weight gain. The impact of fasting insulin and IR on weight gain preceded hyperglycaemia and diminished as glycaemic stage progressed. Copyright © 2018 John Wiley & Sons, Ltd.

  11. Intralipid decreases apolipoprotein M levels and insulin sensitivity in rats.

    Directory of Open Access Journals (Sweden)

    Lu Zheng

    Full Text Available BACKGROUND: Apolipoprotein M (ApoM is a constituent of high-density lipoproteins (HDL. It plays a crucial role in HDL-mediated reverse cholesterol transport. Insulin resistance is associated with decreased ApoM levels. AIMS: To assess the effects of increased free fatty acids (FFAs levels after short-term Intralipid infusion on insulin sensitivity and hepatic ApoM gene expression. METHODS: Adult male Sprague-Dawley (SD rats infused with 20% Intralipid solution for 6 h. Glucose infusion rates (GIR were determined by hyperinsulinemic-euglycemic clamp during Intralipid infusion and plasma FFA levels were measured by colorimetry. Rats were sacrificed after Intralipid treatment and livers were sampled. Human embryonic kidney 293T cells were transfected with a lentivirus mediated human apoM overexpression system. Goto-Kakizaki (GK rats were injected with the lentiviral vector and insulin tolerance was assessed. Gene expression was assessed by real-time RT-PCR and PCR array. RESULTS: Intralipid increased FFAs by 17.6 folds and GIR was decreased by 27.1% compared to the control group. ApoM gene expression was decreased by 40.4% after Intralipid infusion. PPARβ/δ expression was not changed by Intralipid. Whereas the mRNA levels of Acaca, Acox1, Akt1, V-raf murine sarcoma 3611 viral oncogene homolog, G6pc, Irs2, Ldlr, Map2k1, pyruvate kinase and RBC were significantly increased in rat liver after Intralipid infusion. The Mitogen-activated protein kinase 8 (MAPK8 was significantly down-regulated in 293T cells overexpressing ApoM. Overexpression of human ApoM in GK rats could enhance the glucose-lowering effect of exogenous insulin. CONCLUSION: These results suggest that Intralipid could decrease hepatic ApoM levels. ApoM overexpression may have a potential role in improving insulin resistance in vivo and modulating apoM expression might be a future therapeutic strategy against insulin resistance in type 2 diabetes.

  12. Association of Serum Ferritin Levels with Metabolic Syndrome and Insulin Resistance.

    Science.gov (United States)

    Padwal, Meghana K; Murshid, Mohsin; Nirmale, Prachee; Melinkeri, R R

    2015-09-01

    The impact of CVDs and Type II DM is increasing over the last decade. It has been estimated that by 2025 their incidence will double. Ferritin is one of the key proteins regulating iron homeostasis and is a widely available clinical biomarker of iron status. Some studies suggest that prevalence of atherosclerosis and insulin resistance increases significantly with increasing serum ferritin. Metabolic syndrome is known to be associated with increased risk of atherosclerosis as well as insulin resistance. The present study was designed to explore the association of serum ferritin levels with metabolic syndrome and insulin resistance. The present study was prospective, cross sectional. The study protocol was approved by IEC. The study group consisted of 90 participants (50 cases of metabolic syndrome and 40 age and sex matched controls). Diagnosis of metabolic syndrome was done as per NCEP ATP III criteria. Estimation of serum Ferritin and Insulin was done by Chemiluminescence Immunoassay (CLIA) while Glucose by Glucose Oxidase and Peroxidase (GOD-POD) method. Insulin Resistance was calculated by HOMA IR score. Data obtained was statistically analysed by using student t-test. We found statistically significant rise in the levels of serum ferritin (p=syndrome as compared with controls. High serum ferritin levels though within normal range are significantly associated with both metabolic syndrome and insulin resistance.

  13. Relationship between Insulin Levels and Nonpsychotic Dementia: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Qiu-xia Pan

    2017-01-01

    Full Text Available Objectives. To explore the relationship between insulin levels and nonpsychotic dementia. Methods. Six electronic databases (PubMed, Cochrane, SCI, CNKI, VIP, and Wanfang were searched from January 1, 2007, to March 1, 2017. Experimental or observational studies that enrolled people with nonpsychotic dementia or abnormal insulin levels in which insulin levels or MMSE scores (events in nonpsychotic dementia were the outcome measures. Random-effects models were chosen for this meta-analysis. Sample size, mean, s.d., and events were primarily used to generate effect sizes (with the PRIMA registration number CRD42017069860. Results. 50 articles met the final inclusion criteria. Insulin levels in cerebrospinal fluid were lower (Hedges’ g = 1.196, 95% CI = 0.238 to 2.514, and P=0.014, while the levels in peripheral blood were higher in nonpsychotic dementia patients (Hedges’ g = 0.853 and 95% CI = 0.579 to 1.127, and MMSE scores were significantly lower in the high insulin group than in the healthy control group (Hedges’ g = 0.334, 95% CI = 0.249 to 0.419, and P=0.000. Conclusions. Our comprehensive results indicate that blood insulin levels may increase in patients with nonpsychotic dementia.

  14. Lack of relationship between plasma insulin and glucogen levels and angiographically-documented coronary atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Mookherjee, S; Potts, J L; Hill, N E; Warner, R; Raheja, K L; Patel, D G; Vardan, S; Smulyan, H [Upstate Medical Center, Syracuse, NY (USA)

    1983-10-01

    In 120 consecutive patients undergoing diagnostic coronary arteriography, fasting blood glucose, plasma insulin, glucagon, serum cholesterol and triglyceride concentrations were measured. The insulin-glucose ratio and insulin-glucagon ratio were calculated. Forty-five patients had normal coronary arteries, 19 had single vessel coronary artery disease and 56 patients had multiple vessel disease. Fasting blood glucose was >120 mg/100 ml in 37 patients (group A) and included 9 of the 10 known diabetics, 3 of whom were being treated with insulin. Seventy-seven patients included in group B had fasting blood glucose concentration <120 mg/100 ml. Patients with multiple vessel coronary disease in either group had higher blood glucose and cholesterol concentrations than those with normal coronary arteries or glucagon levels nor increased insulin-glucose or insulin-glucagon ratios. With comparable extent of coronary artery disease patients in group A had higher plasma insulin levels and insulin-glucagon ratios than those in group B, but no correlation exists between the presence of extent of coronary atherosclerosis and these variables in either group. Thus, neither fasting plasma insulin level nor insulin-glucagon ratio predicts the status of underlying coronary atherosclerosis in either diabetes or nondiabetes.

  15. Clinical significance of determination of serum cortisol and insulin levels in neonates with asphyxia

    International Nuclear Information System (INIS)

    Yao Yingfei; Chen Linxing; Chen Sihong; Zhang Jinchi; Huang Hua

    2004-01-01

    Objective: To investigate the clinical significance of the changes of serum cortisol and insulin levels in neonates with asphyxia. Methods: Serum cortisol levels were determined with CLIA and serum insulin levels with RIA in 38 neonates with asphyxia (mild degree 20, advanced 18) and 30 controls. Results: 1) In mild cases, serum insulin levels were significantly higher than those in controls (p<0.01) and serum cortisol levels were very significantly higher (p<0.001). 2) In advanced cases, both serum insulin and cortisol levels were very significantly higher than those in the controls (p<0.001). Conclusion: Hypoxia in the neonates with asphyxia is a very severe stress and will induce hypersecretion of cortisol and hyperglycemia which is detrimental to the patients. However hypersecretion of insulin will result in hypoglycemia, which is also very damaging. Physicians in charge should be aware of these possibilities and deal with them appropriately

  16. Solutes transport characteristics in peritoneal dialysis: variations in glucose and insulin serum levels.

    Science.gov (United States)

    da Silva, Dirceu R; Figueiredo, Ana E; Antonello, Ivan C; Poli de Figueiredo, Carlos E; d'Avila, Domingos O

    2008-01-01

    Differences in small solutes transport rate (SSTR) during peritoneal dialysis (PD) may affect water and solutes removal. Patients with high SSTR must rely on shorter dwell times and increased dialysate glucose concentrations to keep fluid balance. Glucose absorption during peritoneal dialysis (PD), besides affecting glucose and insulin metabolism, may induce weight gain. The study aimed at examining acute glucose and insulin serum level changes and other potential relationships in PD patients with diverse SSTR. This cross-sectional study used a modified peritoneal equilibration test (PET) that enrolled 34 prevalent PD patients. Zero, 15, 30, 60, 120, 180, and 240-minute glucose and insulin serum levels were measured. Insulin resistance index was assessed by the homeostasis model assessment (HOMA-IR) formula. SSTR categories were classified by quartiles of the four-hour dialysate/serum creatinine ratio (D(4)/P(Cr)). Demographic and clinical variables were evaluated, and the body mass index (BMI) was estimated. Correlations among variables of interest and categories of SSTR were explored. Glucose serum levels were significantly different at 15, 30, and 60 minutes between high and low SSTR categories (p = 0.014, 0.009, and 0.022). Increased BMI (25.5 +/- 5.1) and insulin resistance [HOMA-IR = 2.60 (1.40-4.23)] were evidenced overall. Very strong to moderate correlations between insulin levels along the PET and HOMA-IR (r = 0.973, 0.834, 0.766, 0.728, 0.843, 0.857, 0.882) and BMI (r = 0.562, 0.459, 0.417, 0.370, 0.508, 0.514, 0.483) were disclosed. CONCLUSIONS; Early glucose serum levels were associated with SSTR during a PET. Overweight or obesity and insulin resistance were prevalent. An association between insulin serum levels and BMI was demonstrated.

  17. Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents.

    Science.gov (United States)

    Lira, Fábio S; Rosa, Jose C; Pimentel, Gustavo D; Santos, Ronaldo V; Carnier, June; Sanches, Priscila L; de Piano, Aline; de Souza, Claudio T; Tock, Lian; Tufik, Sergio; de Mello, Marco T; Seelaender, Marília; Oller do Nascimento, Claudia M; Oyama, Lila M; Dâmaso, Ana R

    2012-09-18

    The purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy. The present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15-19 y) with a body mass index > 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. In addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR). The most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. In addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels. The present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. In addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.

  18. Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents

    Directory of Open Access Journals (Sweden)

    Lira Fábio S

    2012-09-01

    Full Text Available Abstract Aim The purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy. Design The present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15–19 y with a body mass index > 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. In addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR. Results The most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. In addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels. Conclusions The present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. In addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.

  19. Plasma insulin levels are increased by sertraline in rats under oral glucose overload

    Directory of Open Access Journals (Sweden)

    Gomez R.

    2001-01-01

    Full Text Available Recognition and control of depression symptoms are important to increase patient compliance with treatment and to improve the quality of life of diabetic patients. Clinical studies indicate that selective serotonin reuptake inhibitors (SSRI are better antidepressants for diabetic patients than other drugs. However, preclinical trials have demonstrated that not all SSRI reduce plasma glucose levels. In fact, fluoxetine increases and sertraline decreases glycemia in diabetic and non-diabetic rats. In the present study we evaluated plasma insulin levels during fasting and after glucose overload after treatment with sertraline. Adult male Wistar rats were fasted and treated with saline or 30 mg/kg sertraline and submitted or not to glucose overload (N = 10. Blood was collected and plasma insulin was measured. The mean insulin levels were: fasting group: 25.9 ± 3.86, sertraline + fasting group: 31.10 ± 2.48, overload group: 34.1 ± 3.40, and overload + sertraline group: 43.73 ± 5.14 µU/ml. Insulinemia was significantly increased in the overload + sertraline group. There were no differences between the other groups. No difference in glucose/insulin ratios could be detected between groups. The overload + sertraline group was the only one in which a significant number of individuals exceeded the upper confidence limit of insulin levels. This study demonstrates that sertraline increases glucose-stimulated insulin secretion without any change in peripheral insulin sensitivity.

  20. Effect of naloxone on plasma insulin, insulin-like growth factor I, and its binding protein 1 in patients with polycystic ovarian disease.

    Science.gov (United States)

    Laatikainen, T; Anttila, L; Suikkari, A M; Ruutiainen, K; Erkkola, R; Seppälä, M

    1990-09-01

    Insulin and insulin-like growth factors (IGFs) stimulate ovarian steroidogenesis, and hyperinsulinemia is often accompanied by hyperandrogenemia in women with polycystic ovarian disease (PCOD). Because opioid peptides are involved in the regulation of insulin secretion, we studied the effect of naloxone-induced opiate receptor blockade on the circulating levels of insulin, IGF-I, and IGF binding protein 1 (IGFBP-1) in 13 nonobese and 7 obese PCOD patients and in 6 healthy subjects. In obese PCOD patients, the mean basal insulin concentration was significantly higher and the IGFBP-1 concentration lower than in nonobese PCOD patients. Plasma IGF-I levels were elevated both in obese and nonobese PCOD patients. After an intravenous bolus of 10 mg naloxone, no significant changes were found in the circulating insulin or IGF-I levels, whereas IGFBP-1 levels decreased in nonobese PCOD patients and remained low in obese PCOD patients. No significant decrease was found in healthy subjects. These results suggest that, in addition to insulin, endogenous opioids are involved in the regulation of serum IGFBP-1 level.

  1. Correlation between Body Mass Index and Insulin Levels in Premenopausal Women

    Directory of Open Access Journals (Sweden)

    Anastasia Sachinidou

    2017-12-01

    Full Text Available Obesity is one of the most important problems of modern societies, and is considered a modern plague which tends to evolve to a global pandemic. Premenopausal women, most of the times, manifest hormonal dysfunctions and dysfunctions in their metabolism. The consequences are weight gain, heart diseases, hypertension and diabetes mellitus type 2. Purpose: The purpose of this study was to examine if vitamin D levels and Glycosylated hemoglobin are affected by exercise and if there is a connection between Body Mass Index (BMI and insulin. Method: The research involved 48 healthy premenopausal women who answered questionnaires which included questions about their height, weight, waist circumference, lifestyle and history of menstruation. This questionnaire, after due electronic approval, was based on a model of the German Sports and Research Centre (Karlsruhe Institut Fuer Sport und Sportwissenschaft. Women, after having completed a consent form, were also subjected to laboratory testing to determine their insulin, vitamin D levels and Glycosylated hemoglobin levels. To specify the vitamin D and insulin levels a method of direct chemiluminescence was used, and Glycosylated hemoglobin identification was specified using an automated light metering method. Statistical analysis performed using ΙΒΜ SPSS 22. Results: At the premenopausal women (41+/-7ετών (BMI24+/-4 kg/m2 a significant impact during the time of the exercises in the glycosylated hemoglobin (p = 0.038 0.05 regarding the levels of Glycosylated hemoglobin and the combination of exercise with other physical activities. Finally, a significant correlation between BMI and insulin (p=0.001<0.05 was detected. Furthermore, there was no statistically significant difference found in vitamin D levels relative to physical activity. Conclusion: During the research it was found that BMI influences the secretion of insulin, and insulin resistance that is a metabolism disorder, is a result of

  2. The Association Between IGF-I and Insulin Resistance

    DEFF Research Database (Denmark)

    Friedrich, Nele; Thuesen, Betina; Jørgensen, Torben

    2012-01-01

    OBJECTIVEIGF-I has an almost 50% amino acid sequence homology with insulin and elicits nearly the same hypoglycemic response. Studies showed that low and high IGF-I levels are related to impaired glucose tolerance and to a higher risk of type 2 diabetes. The aim of the current study was to evaluate...... the association between IGF-I level and insulin resistance in a Danish general population.RESEARCH DESIGN AND METHODSIncluded were 3,354 adults, aged 19-72 years, from the cross-sectional Health2006 study. The homeostasis model assessment of insulin resistance (HOMA-IR) was used as the index to estimate insulin...... with intermediate (Q3) IGF-I levels. These associations remained statistically significant after the exclusion of subjects with type 2 diabetes and by using the updated computer HOMA2-IR model.CONCLUSIONSLow- and high-normal IGF-I levels are both related to insulin resistance. The biological mechanism...

  3. Insulin transport into the brain and cerebrospinal fluid.

    Science.gov (United States)

    Begg, Denovan P

    2015-01-01

    The pancreatic hormone insulin plays a well-described role in the periphery, based principally on its ability to lower circulating glucose levels via activation of glucose transporters. However, insulin also acts within the central nervous system (CNS) to alter a number of physiological outcomes ranging from energy balance and glucose homeostasis to cognitive performance. Insulin is transported into the CNS by a saturable receptor-mediated process that is proposed to be dependent on the insulin receptor. Transport of insulin into the brain is dependent on numerous factors including diet, glycemia, a diabetic state and notably, obesity. Obesity leads to a marked decrease in insulin transport from the periphery into the CNS and the biological basis of this reduction of transport remains unresolved. Despite decades of research into the effects of central insulin on a wide range of physiological functions and its transport from the periphery to the CNS, numerous questions remain unanswered including which receptor is responsible for transport and the precise mechanisms of action of insulin within the brain. © 2015 Elsevier Inc. All rights reserved.

  4. Influence of insulin therapy on circulating ghrelin and insulin-like ghrelinowth factor-1(IGF-1) levels in children with type-1 diabetes mellitus

    International Nuclear Information System (INIS)

    Moawad, A.T.; Nassar, E.M.; Mostafa, A.M.; Mohammed, S.K.

    2009-01-01

    Diabetes mellitus type 1 (IDDM)is a chronic disease associated with alterations in the growth hormone/insulin -like growth factor (GH-IGF) system and ghrelin level which may lead to changes in metabolic control. This study aimed to evaluate the circulating levels of the gut-derived peptides (ghrelin and insulin-like growth factors (IGF s ) in children with IDDM and to link these two peptides with the glucose level in diabetic children at diagnoses and after insulin therapy. Design and methods: the studied group consisted of 30 newly diagnosed diabetic children (17 females and 13 males) diagnosed in paediatric diabetes unit, children's hospital, Ain shams university. Their age ranged from (6.2-11.8) years with mean of 10.10± 1.74 years. Twenty non diabetic healthy children matching in age and sex served as controls. Serum ghrelin was determined by enzyme linked immuno absorbanet assay (ELISA), while IGF-1 and insulin-like growth factors binding proteins -1 and 3 (IGFBP s ) were assessed by radioimmunoassay(RIA). Results: body mass index (BMI) in patients was significantly decreased in the diabetic group as compared to the healthy group at diagnosis. After insulin therapy BMI was significantly increase as compared to its value at diagnosis (p< 0.05) such increase was not significant on comparing to controls. Regarding blood glucose level there was very highly significant decrease in the level of HBAI (glycolated HB) in diabetic patients after insulin therapy (p<0.0001) than at diagnosis . The mean ghrelin level was highly significantly decreased in diabetic children at diagnosis and after insulin therapy as compared to controls (p<0.0001). No differences were found in the mean ghrelin levels in diabetic children at diagnosis or after insulin therapy.conclusions : the decrease in mean gherlin levels in this study at diagnosis and after therapy could reflect an attempt by the body to decrease the glucose level and thus may prevent hyperglycemia in diabetic patients

  5. Skeletal Muscle Sorbitol Levels in Diabetic Rats with and without Insulin Therapy and Endurance Exercise Training

    Science.gov (United States)

    Sánchez, O. A.; Walseth, T. F.; Snow, L. M.; Serfass, R. C.; Thompson, L. V.

    2009-01-01

    Sorbitol accumulation is postulated to play a role in skeletal muscle dysfunction associated with diabetes. The purpose of this study was to determine the effects of insulin and of endurance exercise on skeletal muscle sorbitol levels in streptozotocin-induced diabetic rats. Rats were assigned to one experimental group (control sedentary, control exercise, diabetic sedentary, diabetic exercise, diabetic sedentary no-insulin). Diabetic rats received daily subcutaneous insulin. The exercise-trained rats ran on a treadmill (1 hour, 5X/wk, for 12 weeks). Skeletal muscle sorbitol levels were the highest in the diabetic sedentary no-insulin group. Diabetic sedentary rats receiving insulin had similar sorbitol levels to control sedentary rats. Endurance exercise did not significantly affect sorbitol levels. These results indicate that insulin treatment lowers sorbitol in skeletal muscle; therefore sorbitol accumulation is probably not related to muscle dysfunction in insulin-treated diabetic individuals. Endurance exercise did not influence intramuscular sorbitol values as strongly as insulin. PMID:20016800

  6. Relationship between serum insulin level and age and sex in 980 patients with essential hypertension

    International Nuclear Information System (INIS)

    Cai Jianlin; Ji Naijun; Mei Yubin; Wang Chengyao; Fan Bifu; Chen Donghai; Guan Li; Tong Lijun; Li Fuyuan; Gao Meiying

    2004-01-01

    Objective: To investigate the change of serum insulin level in essential hypertension patients and its relationship with age and sex. Methods: The levels of serum insulin were determined with radioimmunoassay in 980 essential hypertension patients and 120 controls. Results: The levels of serum insulin in the essential hypertension patients were significantly higher than those in the controls (t=4.280, P<0.01). However, there were no significant differences among the levels in different sex and age groups. The same held true for women before and after menopause as well as different stages of hypertension. Conclusion: The average serum insulin level in EH patients was significantly higher than the level in controls, and had positive correlation to mean arterial pressure. But no significant differences were found among different sex and age groups, so serum insulin could be a new independent risk factor of essential hypertension

  7. Fatty Acids, Obesity and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Peter Arner

    2015-04-01

    Full Text Available Objective: Although elevated free fatty acid (FFA levels in obesity have been considered to be of importance for insulin resistance, a recent meta-analysis suggested normal FFA levels in obese subjects. We investigated fasting circulating FFA and glycerol levels in a large cohort of non-obese and obese subjects. Methods: Subjects recruited for a study on obesity genetics were investigated in the morning after an overnight fast (n = 3,888. Serum FFA (n = 3,306, plasma glycerol (n = 3,776, and insulin sensitivity index (HOMA-IR,n = 3,469 were determined. Obesity was defined as BMI ≥ 30 kg/m2 and insulin resistance as HOMA-IR ≥ 2.21. Results: In obese subjects, circulating FFA and glycerol levels were higher than in non-obese individuals (by 26% and 47%, respectively; both p Conclusion: Circulating FFA and glycerol levels are markedly elevated in obesity but only marginally influenced by insulin resistance and type 2 diabetes. Whether these differences persist during diurnal variations in circulating FFA/glycerol, remains to be established.

  8. Effect of meal frequency on glucose and insulin levels in women with polycystic ovary syndrome: a randomised trial.

    Science.gov (United States)

    Papakonstantinou, E; Kechribari, I; Mitrou, P; Trakakis, E; Vassiliadi, D; Georgousopoulou, E; Zampelas, A; Kontogianni, M D; Dimitriadis, G

    2016-05-01

    The aim of the study was to compare the effect of two-meal patterns (three vs six meals per day) on glucose and insulin levels in women with polycystic ovary syndrome (PCOS). In a randomised, crossover, 24-week study, 40 women with PCOS, aged 27±6 years, body mass index 27±6 kg/m(2), followed a weight maintenance diet (% carbohydrates:protein:fat, 40:25:35), consumed either as a three- or a six-meal pattern, with each intervention lasting for 12 weeks. Anthropometric measurements, diet compliance and subjective hunger, satiety and desire to eat were assessed biweekly. All women underwent an oral glucose tolerance test (OGTT) with 75 g glucose for measurement of plasma glucose and insulin at the beginning and end of each intervention. HaemoglobinA1c (HbA1c), blood lipids and hepatic enzymes were measured at the beginning and end of each intervention. Body weight remained stable throughout the study. Six meals decreased significantly fasting insulin (P=0.014) and post-OGTT insulin sensitivity (Matsuda index, P=0.039) vs three meals. After incorporation of individual changes over time, with adjustment for potential confounders, the only variable that remained significant was the Matsuda index, which was then used in multivariate analysis and general linear models. Six meals improved post-OGTT insulin sensitivity independently of age and body weight vs three meals (P=0.012). No significant differences were found between six and three meals for glucose, HbA1c, blood lipids, hepatic enzymes, subjective desire to eat and satiety. Six meals had a more favourable effect on post-OGTT insulin sensitivity in women with PCOS compared with isocaloric three meals.

  9. Study on the relationship between the serum adiponectin and insulin levels in female children with simple obesity

    International Nuclear Information System (INIS)

    Bai Hua

    2007-01-01

    Objective: To study the relationship between the serum adiponectin and insulin levels in female children with simple obesity. Methods: Levels of serum adiponectin and insulin were detected with RIA in 32 female children with simple obesity and 35 controls. Results: In the patients, the serum adiponectin levels were significantly lower than those in controls (P < 0.01), while the serum insulin levels were significantly higher (P < 0.01). Serum adiponectin and insulin levels were mutually negatively correlate. Conclusion: There is a close relationship between the serum adiponectin and insulin levels in children with simple obesity. (authors)

  10. Heterozygous deficiency of endoglin decreases insulin and hepatic triglyceride levels during high fat diet.

    Directory of Open Access Journals (Sweden)

    Daniel Beiroa

    Full Text Available Endoglin is a transmembrane auxiliary receptor for transforming growth factor-beta (TGF-beta that is predominantly expressed on proliferating endothelial cells. It plays a wide range of physiological roles but its importance on energy balance or insulin sensitivity has been unexplored. Endoglin deficient mice die during midgestation due to cardiovascular defects. Here we report for first time that heterozygous endoglin deficiency in mice decreases high fat diet-induced hepatic triglyceride content and insulin levels. Importantly, these effects are independent of changes in body weight or adiposity. At molecular level, we failed to detect relevant changes in the insulin signalling pathway at basal levels in liver, muscle or adipose tissues that could explain the insulin-dependent effect. However, we found decreased triglyceride content in the liver of endoglin heterozygous mice fed a high fat diet in comparison to their wild type littermates. Overall, our findings indicate that endoglin is a potentially important physiological mediator of insulin levels and hepatic lipid metabolism.

  11. Serum levels of insulin-like growth factor binding protein-1 and ovulatory responses to clomiphene citrate in women with polycystic ovarian disease.

    Science.gov (United States)

    Tiitinen, A E; Laatikainen, T J; Seppälä, M T

    1993-07-01

    To study the serum levels of insulin, insulin-like growth factor I (IGF-I), and insulin-like growth factor binding protein-1 (IGFBP-1) in relation to clomiphene citrate (CC) responsiveness in women with polycystic ovarian disease (PCOD). Prospective. PATIENTS, SETTING: Twenty-three women with PCOD admitted consecutively to the University Infertility Clinic, a tertiary referral center. Blood samples were taken at fasting state and during oral glucose tolerance test (OGTT) for the determination of insulin, IGF-I, and IGFBP-1. A dose of 50 to 200 mg/d CC was given for ovulation induction. With CC treatment, ovulation was achieved in 13 of 23 PCOD patients. The IGFBP-1 concentration was lower in CC nonresponders than in CC responders (20.5 +/- 4.0 ng/mL versus 41.0 +/- 8.5 ng/mL) (P PCOD patients. Lean CC nonresponders (n = 7) had almost threefold lower serum IGFBP-1 levels than lean CC responders (n = 6) (24.0 +/- 3.1 ng/mL versus 61.8 +/- 8.6 ng/mL) (P PCOD patients, the IGFBP-1 levels were low irrespective of CC responsiveness (14.8 +/- 8.0 ng/mL versus 16.7 +/- 7.2 ng/mL). The differences remained during OGTT. The concentrations of IGF-I, insulin, sex hormone-binding globulin, LH, FSH, and androgens showed no significant differences between CC responders and nonresponders. There was an inverse correlation between serum insulin and IGFBP-1 levels in obese PCOD patients, whereas this was not seen in lean patients. In lean PCOD patients, low serum IGFBP-1 concentration is related to CC unresponsiveness by a mechanism unrelated to insulin.

  12. Influence of insulin on beta-endorphin plasma levels in obese and normal weight subjects.

    Science.gov (United States)

    Brunani, A; Pincelli, A I; Pasqualinotto, L; Tibaldi, A; Baldi, G; Scacchi, M; Fatti, L M; Cavagnini, F

    1996-08-01

    To establish the possible role of hyperinsulinemia in the elevation of plasma beta-endorphin (beta-EP) levels observed in obese patients after an oral glucose load. Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp. Two groups of six (age: 22-39 y, BMI: 30-48 kg/m2) and eight obese men (age: 18-37 y, BMI: 35-45 kg/m2), respectively, and five normal weight healthy men (age: 22-30 y, BMI 22-23 kg/m2). Glucose, insulin and beta-EP levels at baseline and every 30 min until 180 min during the OGTT; glucose, insulin, C-peptide and beta-EP concentrations at baseline and in steady state condition (i.e. during the last 30 min of insulin infusion) in the euglycemic-hyperinsulinemic clamp studies. In the six obese patients undergoing the OGTT a significant elevation of beta-EP plasma levels was observed between 60 and 90 min after glucose ingestion. In the clamp studies no significant differences in beta-EP plasma levels, blood glucose and serum insulin were observed between obese and normal weight subjects both at baseline and at steady state. A markedly diminished insulin sensitivity along with a lower inhibition of C-peptide during insulin infusion was observed in obese patients compared to control subjects. A rise in serum insulin levels unaccompanied by a concomitant increase in blood glucose concentration is unable to elicit a beta-EP response in obese patients.

  13. Lemon detox diet reduced body fat, insulin resistance, and serum hs-CRP level without hematological changes in overweight Korean women.

    Science.gov (United States)

    Kim, Mi Joung; Hwang, Jung Hyun; Ko, Hyun Ji; Na, Hye Bock; Kim, Jung Hee

    2015-05-01

    The lemon detox program is a very low-calorie diet which consists of a mixture of organic maple and palm syrups, and lemon juice for abstinence period of 7 days. We hypothesized that the lemon detox program would reduce body weight, body fat mass, thus lowering insulin resistance and known risk factors of cardiovascular disease. We investigated anthropometric indices, insulin sensitivity, levels of serum adipokines, and inflammatory markers in overweight Korean women before and after clinical intervention trial. Eighty-four premenopausal women were randomly divided into 3 groups: a control group without diet restriction (Normal-C), a pair-fed placebo diet group (Positive-C), and a lemon detox diet group (Lemon-D). The intervention period was 11 days total: 7 days with the lemon detox juice or the placebo juice, and then 4 days with transitioning food. Changes in body weight, body mass index, percentage body fat, and waist-hip ratio were significantly greater in the Lemon-D and Positive-C groups compared to the Normal-C group. Serum insulin level, homeostasis model assessment insulin resistance scores, leptin, and adiponectin levels decreased in the Lemon-D and Positive-C groups. Serum high-sensitive C-reactive protein (hs-CRP) levels were also reduced only in the Lemon-D group. Hemoglobin and hematocrit levels remained stable in the Lemon-D group while they decreased in the Positive-C and Normal-C groups. Therefore, we suppose that the lemon detox program reduces body fat and insulin resistance through caloric restriction and might have a potential beneficial effect on risk factors for cardiovascular disease related to circulating hs-CRP reduction without hematological changes. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The Effects of Reduction Mammaplasty on Serum Leptin Levels and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Hakan Uzun

    2015-01-01

    Full Text Available Background. The reduction mammaplasty has been a well-executed and known procedure in which considerable amount of fatty tissue is removed from the body. The authors aimed to show the effects of the reduction mammaplasty on serum leptin levels and insulin resistance. Methods. 42 obese female patients who had gigantomastia were operated on. We recorded patients’ demographic and preoperative data, including age, weight, height, and body mass index. Fasting serum leptin, glucose, and insulin levels were noted. Homeostasis model assessment scores were calculated. At the postoperative 8th week, patients were reevaluated in terms of above parameters assessing the presence of any difference. Results. Serum leptin levels were decreased postoperatively and the decrease was statistically significant. We were able to show a decrease in homeostasis model assessment score, which indicated an increase in insulin sensitivity, and this change was statistically significant. A significant correlation between body mass index and leptin change was found postoperatively. Conclusion. Reduction mammaplasty is not solely an aesthetic procedure but it decreases serum leptin levels and increases insulin sensitivity, which may help obese women to reduce their cardiovascular risk.

  15. Retinol-Binding Protein 4 and Insulin Resistance in Polycystic Ovary Syndrome

    OpenAIRE

    Hutchison, Samantha K.; Harrison, Cheryce; Stepto, Nigel; Meyer, Caroline; Teede, Helena J.

    2008-01-01

    OBJECTIVE?Polycystic ovary syndrome (PCOS) is an insulin-resistant state with insulin resistance being an established therapeutic target; however, measurement of insulin resistance remains challenging. We aimed to 1) determine serum retinol-binding protein 4 (RBP4) levels (purported to reflect insulin resistance) in women with PCOS and control subjects, 2) examine the relationship of RBP4 to conventional markers of insulin resistance, and 3) examine RBP4 changes with interventions modulating ...

  16. Serum cortisol level and its correlation to serum insulin and fasting blood sugar levels in patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Chen Jianzhong; Zhang Jun

    2004-01-01

    Objective: To investigate the change of serum cortisol levels and its correlation to blood sugar and serum insulin levels in patients with type 2 diabetes mellitus. Methods: Blood sugar with oxidase method and serum cortisol insulin levels with RIA (8 AM fasting specimen) were measured in 26 patients with type 2 diabetes mellitus and 30 controls. Results: The serum cortisol levels in the diabetic patients were significantly higher than those in the controls (P<0.01). The cortisol levels were positively correlated to the blood sugar levels (r=0.32, p<0.01), but not correlated to insulin levels. Conclusion: There were cortisol secretion disturbances in patients with type 2 diabetes

  17. Insulin and leptin levels in overweight and normal-weight Iranian adolescents: The CASPIAN-III study

    Directory of Open Access Journals (Sweden)

    Ehsan Bahrami

    2014-01-01

    Full Text Available Background: In this study, we aim to compare insulin and leptin levels in adolescents with or without excess weight and in those with or without abdominal obesity. Materials and Methods : This case-control study was conducted among 486 samples. We randomly selected 243 overweight and an equal number of normal-weight adolescents from among participants of the third survey of a national surveillance program entitled "Childhood and Adolescence Surveillance and PreventIon of Adult Non-communicable diseases study." Serum insulin and leptin were compared between two groups and their correlation was determined with other variables. Results: The mean age and body mass index (BMI of participants were 14.10 ± 2.82 years and 22.12 ± 6.49 kg/m 2 , respectively. Leptin and insulin levels were higher in overweight than in normal-weight adolescents (P < 0.05. Leptin level was higher in children with abdominal obesity than in their other counterparts (P < 0.001. Leptin level was correlated with age, fasting blood glucose, BMI, and insulin level. Conclusion: Insulin and leptin levels were higher among overweight and obese children, which may reflect insulin and leptin-resistance. Given the complications of excess weight from early life, prevention and controlling childhood obesity should be considered as a health priority.

  18. Effect of Artemisia dracunculus Administration on Glycemic Control, Insulin Sensitivity, and Insulin Secretion in Patients with Impaired Glucose Tolerance.

    Science.gov (United States)

    Méndez-Del Villar, Miriam; Puebla-Pérez, Ana M; Sánchez-Peña, María J; González-Ortiz, Luis J; Martínez-Abundis, Esperanza; González-Ortiz, Manuel

    2016-05-01

    To evaluate the effect of Artemisia dracunculus on glycemic control, insulin sensitivity, and insulin secretion in patients with impaired glucose tolerance (IGT). A randomized, double blind, placebo-controlled clinical trial was performed in 24 patients with diagnosis of IGT. Before and after the intervention, glucose and insulin levels were measured every 30 min for 2 h after a 75-g dextrose load, along with glycated hemoglobin A1c (A1C) and lipid profile. Twelve patients received A. dracunculus (1000 mg) before breakfast and dinner for 90 days; the remaining 12 patients received placebo. Area under the curve (AUC) of glucose and insulin, total insulin secretion, first phase of insulin secretion, and insulin sensitivity were calculated. Wilcoxon signed-rank, Mann-Whitney U, and chi-square tests were used for statistical analyses. The institutional ethics committee approved the protocol. After A. dracunculus administration, there were significant decreases in systolic blood pressure (SBP; 120.0 ± 11.3 vs. 113.0 ± 11.2 mmHg, P AUC of insulin (56,136.0 ± 27,426.0 vs. 44,472.0 ± 23,370.0 pmol/L, P AUC of insulin, and total insulin secretion with a significant increase in HDL-C levels.

  19. Insulin initiation status of primary care physicians in Turkey, barriers to insulin initiation and knowledge levels about insulin therapy: A multicenter cross-sectional study.

    Science.gov (United States)

    Ates, Elif; Set, Turan; Saglam, Zuhal; Tekin, Nil; Karatas Eray, Irep; Yavuz, Erdinc; Sahin, Mustafa Kursat; Selcuk, Engin Burak; Cadirci, Dursun; Cubukcu, Mahcube

    2017-10-01

    Our aim was to evaluate the insulin initiation status, barriers to insulin initiation and knowledge levels about treatment administered by primary care physicians (PCP). We conducted our study in accordance with a multicenter, cross-sectional design in Turkey, between July 2015 and July 2016. A questionnaire inquiring demographic features, status of insulin initiation, obstacles to insulin initiation and knowledge about therapy of the PCPs was administered during face-to-face interviews. 84 PCPs (19%) (n=446, mean age=41.5±8.4years, 62.9% male and 90.0% ministry certified family physicians) initiated insulin therapy in the past. Most of the stated primary barriers (51.9%, n=230) were due to the physicians. The most relevant barrier was "lack of clinical experience" with a rate of 19% (n=84 of the total). The average total knowledge score was 5.7±2.0 for the family medicine specialist, and 3.8±2.1 for the ministry certified family physicians (p=0.000, maximum knowledge score could be 10). The status of insulin initiation in Turkey by the primary care physicians is inadequate. Medical education programs and health care systems may require restructuring to facilitate insulin initiation in primary care. Copyright © 2017 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

  20. Cytokines and their association with insulin resistance in obese pregnant women with different levels of physical activity.

    Science.gov (United States)

    Nayak, Minakshi; Eekhoff, Marelise E W; Peinhaupt, Miriam; Heinemann, Akos; Desoye, Gernot; van Poppel, Mireille N M

    2016-01-01

    Cytokines contribute to insulin resistance in pregnancy, but the role of distinct cytokines is not fully understood. To study whether cytokines produced by tissues other than skeletal muscle are associated with glucose and insulin metabolism activity in overweight and obese women and to study whether these associations can be modified by physical activity. A longitudinal study with 44 overweight and obese pregnant women was conducted. Changes in cytokines levels (IFN-γ, IP-10, IL1-α, MIP1-α, adiponectin and leptin) and ICAM1 from early (15wk) to late (32wk) pregnancy were determined. Physical activity was measured objectively with accelerometers. In linear regression models, the associations between (changes in) cytokine levels and fasting glucose, fasting insulin and HOMA-IR were studied. Both IFN-γ and IP-10 levels increased from early to late pregnancy, and adiponectin levels decreased. IFN-γ and IP-10 were positively associated with fasting glucose, whereas IL-1α, ICAM1 and adiponectin were inversely associated with insulin and insulin resistance. The association of IL-1α with insulin and insulin resistance was only found in women with low levels of physical activity. IFN-γ, IP-10, IL1-α, ICAM1, and adiponectin may play a role in glucose and insulin metabolism in pregnancy. The relationship of IL-1α with insulin and insulin resistance might be moderated by levels of physical activity. Further studies are required to confirm the role of these cytokines in glucose and insulin metabolism in obese pregnant women. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Differences in homeostatic model assessment (HOMA) values and insulin levels after vitamin D supplementation in healthy men: a double-blind randomized controlled trial.

    Science.gov (United States)

    Tepper, S; Shahar, D R; Geva, D; Ish-Shalom, S

    2016-06-01

    Vitamin D is thought to play a role in glucose metabolism. The aim of the present study was to determine the effect of vitamin D supplementation on markers of insulin sensitivity and inflammation in men without diabetes with vitamin D deficiency/insufficiency. In this 1-year double-blind randomized controlled trial, 130 men aged 20-65 years (mean age 47.52 ± 11.84 years) with serum 25-hydroxyvitamin D levels HOMA-IR) values between groups. Levels of insulin and HOMA-IR values remained steady during the study period in the treatment group but increased by 16% in the control group (p = 0.038 and p = 0.048, respectively). Vitamin D supplementation administered for 12 months in healthy men maintained insulin levels and HOMA-IR values relative to the increase in the control group. Further studies are needed to establish the long-term effect of vitamin D supplementation on the risk of diabetes. © 2016 John Wiley & Sons Ltd.

  2. The radioimmunological determination of the insulin level in the early postnatal period of the pigs

    International Nuclear Information System (INIS)

    Nowak, J.; Staszak, B.; Slebodzinski, A.

    1980-01-01

    The insulin level determined by means of the radioimmunoassay, in piglets, 1 - 21 days of age revealed marked changes with age of the animals, as illustrated by the hormonal profiles. In general, the postnatal insuline profile was characterized by a quick rise in the serum hormone concentration - the postnatal hiperinsulinemia - observed already in some litters within the first 48 hours of life. The peak of the hormone concentration was followed by a decrease to a relatively constant but low level, between the third day and 10 - 14 day. In the absolute terms, the insulin concentration at 0 - 6 hours averaged from 3.3+-1.42 to 11.0+-1.44 μU/ml and then increased to the maximum from 19.8+-1.44 to 30.3+-8.81 μU/ml (means +- S.E., p<0.01) found between 12 - 36 hour of life. In some of the pigs a low or a high insulin level came by turns. Any insulin level above 16 μU/ml was classified as ''an insulin peak'' and that below 8 μU/ml as ''an insulin depression''. The frequency of the peaks and the depressions per day was the highest during the first 2 days of life, that is during the period known from the highest mortality in this species. The preliminary observation suggest that a high frequency of the insulin depressions is somewhat related to the lower vitality or to the hypoglycemia state. (author)

  3. Study on the relationship between the serum adiponectin and insulin levels in patients with polycystic ovary syndrome (PCOS)

    International Nuclear Information System (INIS)

    Wang Ying; Yang Wen

    2010-01-01

    Objective: To study the relationship between the serum adiponectin and insulin levels in patients with polycystic ovary syndrome (PCOS). Methods: Levels of serum adiponectin and insulin were detected with RIA in 36 patients with polycystic ovary syndrome and 35 controls. Results: In the patients, the serum adiponectin levels were significantly lower than those in controls (P <0.01), while the serum insulin levels were significantly higher (P <0.01). Serum adiponectin and insulin levels were mutually negatively correlated (r =-0.5034, P < 0.01). Conclusion: There is a close relationship between the serum adiponectin and insulin levels in patients with polycystic ovary syndrome. (authors)

  4. Clinical significance of changes of serum leptin and insulin levels in patients with polycystic ovary syndrome

    International Nuclear Information System (INIS)

    Chen Zhaojun; Zhang Lahong; Gao Ying; Ren Xiaohua

    2007-01-01

    Objective: To explore the relationship between the serum leptin, insulin levels and development of polycystic ovary syndrome (PCOS). Methods: Serum leptin and insulin levels (with RIA) were determined in 34 patients with PCOS and 30 controls. Results: The serum leptin and insulin levels in the 34 PCOS patients were significantly higher than those in controls (P<0. 01), and those in obese patients (n=22) were significantly higher than those in non-obese ones (n=12) too(P<0.01). Conclusion: Changes of serum leptin and insulin levels were closely related to the development of PCOS and leptin might be used as a diagnostic indicator for PCOS. (authors)

  5. Exercise effects on fitness, lipids, glucose tolerance and insulin levels in young adults.

    Science.gov (United States)

    Israel, R G; Davidson, P C; Albrink, M J; Krall, J M

    1981-07-01

    The effect of 3 different physical training programs on cardiorespiratory (cr) fitness, fasting plasma lipids, glucose and insulin levels, and scapular skinfold thickness was assessed in 64 healthy college men. Training sessions were held 4 times a week for 5 weeks. The cr fitness improved significantly and skinfold thickness decreased following the aerobic, the pulse workout (interval training), and the anaerobic training compared to the control group. Skinfold thickness, plasma insulin, and triglyceride concentrations were significantly intercorrelated before and after training. The exercise programs had no significant effect on plasma cholesterol, triglycerides, phospholipids, glucose tolerance, or insulin levels. Change in adipose mass was thus dissociated from change in plasma insulin and triglyceride concentrations. It was concluded that in young men plasma triglycerides, the lipid component mostly readily reduced by exercise, were too low to be reduced further by a physical training program.

  6. Serum AMH levels and insulin resistance in women with PCOS.

    Science.gov (United States)

    Sahmay, Sezai; Aydogan Mathyk, Begum; Sofiyeva, Nigar; Atakul, Nil; Azemi, Aslı; Erel, Tamer

    2018-05-01

    To compare the serum AMH levels between women with and without insulin resistance (IR) in polycystic ovary syndrome (PCOS). 293 women with PCOS according to the Rotterdam criteria were enrolled into our study. Insulin resistance was diagnosed according to the Homeostatic model assessment insulin resistant (HOMA-IR) formula and the cut-off point was set to more than 2.5. Women were grouped according to the presence of insulin resistance (IR) (HOMA-IR ≥ 2.5). Serum AMH and other hormones were compared between the IR (+) and IR (-) groups. Additionally, AMH percentiles were (75) constructed; HOMA-IR and BMI values in women with/without IR were compared in different percentiles. Further, HOMA-IR, BMI and AMH values were measured across different PCOS phenotypes. The prevalence of IR was 45%. The prevalence of IR was 57% in women with BMI ≥ 25. Serum AMH levels were not significantly different among women with and without IR. Also, HOMA-IR values were not significant among different AMH percentiles. However, in each AMH percentile BMI were found to be higher in women with IR than in women without IR. The median HOMA-IR values were the highest in women with BMI ≥ 25 in both IR (+) and IR (-) groups. No significant difference was found among PCOS phenotypes in terms of HOMA-IR and BMI. Positive correlations were found between BMI, free testosterone and HOMA-IR. However, no correlation was found between AMH and HOMA-IR. The serum AMH levels between women with IR and without IR in PCOS were not significantly different. Also, we did not reveal a correlation between serum AMH levels and IR in women with PCOS. IR was not correlated with different PCOS phenotypes either. We found a positive correlation between BMI and IR. IR should be investigated in women with PCOS having a BMI ≥ 25, independent of their phenotype or AMH levels. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Measurement of insulin and C-peptide excitatory test levels in gestational diabetes mellitus

    International Nuclear Information System (INIS)

    Du Tongxin; Wang Zizheng

    2001-01-01

    To investigate the function of islet β cells in patients with gestational diabetes mellitus (GDM), serum insulin and C-peptide (C-P) excitatory test levels were measured dynamically by radioimmunoassay in 41 patients with GDM and 30 normal pregnant controls. The results showed that there were significant difference in insulin and C-peptide excitatory test levels between normal pregnancy for 32-40 weeks and patients with GDM (P < 0.001). The secretory peak of insulin occurred at 60 min in normal pregnancy, while at 120 min in patients with GDM, and the recovery postponed in patients with GDM. The peak time for C-P was just as same as that of insulin, but the peak error for C-P between normal pregnant controls and patients with GDM was more larger than that for insulin and it recovered more slowly. It suggested that majority of islet β cells in patients with GDM were good enough for response to islet resistance factors and big stress from pregnancy, and also suggested a relation between pregnancy and islet β cells function

  8. Serum levels of fractalkine are associated with markers of insulin resistance in gestational diabetes.

    Science.gov (United States)

    Ebert, T; Hindricks, J; Kralisch, S; Lossner, U; Jessnitzer, B; Richter, J; Blüher, M; Stumvoll, M; Fasshauer, M

    2014-08-01

    Fractalkine has recently been introduced as an adipokine that improves glucose tolerance. Regulation of fractalkine in gestational diabetes, as well as its association with markers of obesity, glucose and lipid metabolism, inflammation and renal function, has not been elucidated. Circulating fractalkine was quantified by enzyme-linked immunosorbent assay in 74 women with gestational diabetes and 74 healthy, pregnant control subjects matched for age, BMI, and gestational age. Median (interquartile range) levels of fractalkine were not significantly different between the two groups [gestational diabetes: 2.24 (2.16) μg/l; control: 2.45 (1.38) μg/l] (P = 0.461). In multivariate linear regression analysis, fractalkine remained independently associated with homeostasis model assessment of insulin resistance (β = -0.253, P = 0.002) and the proinflammatory adipokine progranulin (β = 0.218, P = 0.007). Circulating fractalkine is not different between women with gestational diabetes and control subjects, but the adipokine is independently associated with markers of insulin resistance and proinflammatory progranulin in pregnancy. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

  9. Insulin resistance and glucose levels in subjects with subclinical hypothyroidism

    International Nuclear Information System (INIS)

    Kahn, S.H.; Fazal, N.; Yasir, M.; Asif, N.; Rafi, T.

    2017-01-01

    To compare insulin resistance and glycemic indicators among subjects with euthyroidism and subclinical hypothyroidism. Study Design: Comparative cross-sectional study. Place and Duration of Study: Department of Pathology and Medicine, PNS Hafeez, Islamabad, in collaboration with the Department of Chemical Pathology and Endocrinology at the Armed Forces Institute of Pathology (AFIP), Rawalpindi, from December 2015 to September 2016. Methodology: Subjects referred for executive screening of apparently healthy population (without any known history of diabetes, hypertension, heart disease or other chronic ailments), were included. Subjects were grouped as euthyroidism and subclinical hypothyroidism. Results: Median (IQR) insulin resistance indices including fasting insulin and Homeostasis Model Assessment for Insulin Resistance in subjects with group-1 (n=176, 87%, Thyroid Stimulating Hormone: 0.5 - 3.5 mIU/L) and group-2 (n=26, 13%, Thyroid Stimulating Hormone: 3.51 - 15 mIU/L) were 7.6 (6.70) vs. 11.4 (13.72, p=0.040) and 1.77 (1.79) vs. 2.8 (3.07, p=0.071). The median differences for fasting plasma glucose were 5.0 (1.0) in group-1 vs. 5.0 (1.47) for Group-2 [p=0.618], and glycated hemoglobin was 5.60 (1.1) vs. 5.60 (1.7, p=0.824). Homeostasis Model Assessment for beta sensitivity index in paradox showed slightly higher values for group-2 [median (IQR) 86.67 (92.94)] than group-1 [111.6 (189.64, p= 0.040)]. Conclusion: Measures of insulin resistance including Homeostasis Model Assessment for Insulin Resistance and fasting insulin levels were significantly different between subjects with euthyroidism and having subclinical hypothyroidism. (author)

  10. Effects of B Vitamins Overload on Plasma Insulin Level and Hydrogen Peroxide Generation in Rats.

    Science.gov (United States)

    Sun, Wuping; Zhai, Mingzhu; Zhou, Qian; Qian, Chengrui; Jiang, Changyu

    2017-08-31

    It has been reported that nicotinamide-overload induces oxidative stress associated with insulin resistance, the key feature of type 2 diabetes mellitus (T2DM). This study aimed to investigate the effects of B vitamins in T2DM. Glucose tolerance tests were carried out in adult Sprague-Dawley rats treated with or without cumulative doses of B vitamins. More specifically, insulin tolerance tests were also carried out in adult Sprague-Dawley rats treated with or without cumulative doses of Vitamin B3. We found that cumulative Vitamin B1 and Vitamin B3 administration significantly increased the plasma H₂O₂ levels associated with high insulin levels. Only Vitamin B3 reduced muscular and hepatic glycogen contents. Cumulative administration of nicotinic acid, another form of Vitamin B3, also significantly increased plasma insulin level and H₂O₂ generation. Moreover, cumulative administration of nicotinic acid or nicotinamide impaired glucose metabolism. This study suggested that excess Vitamin B1 and Vitamin B3 caused oxidative stress and insulin resistance.

  11. Fasting in Ramadan with an insulin pump.

    Science.gov (United States)

    Kesavadev, Jothydev

    2015-05-01

    A good majority of subjects with diabetes on insulin therapies observe fasting during Ramadan. The challenge for the physician and the patient is to manage diabetes without an interruption to fasting by avoiding hypoglycaemia and simultaneously ensuring that blood glucose remain at acceptable safe levels. Insulin Pumps differ from syringes and insulin pens in that it offers a variable basal rate, different type of boluses and associated calculators. The technological advances that pumps offer, help educated subjects pre-programme a reduced basal rate throughout the day. Pumps ensure avoidance of hypoglycaemia and hyperglycaemia and preserve quality of life and enhance confidence in patients during fasting. Due to multiple benefits, insulin pumps are considered the best delivery systems for insulin during the holy month of Ramadan, despite the prerequisites for its optimal output and cost concerns.

  12. An uncommon cause of hypoglycemia: insulin autoimmune syndrome.

    Science.gov (United States)

    Savas-Erdeve, Senay; Yılmaz Agladioglu, Sebahat; Onder, Asan; Peltek Kendirci, Havva Nur; Bas, Veysel Nijat; Sagsak, Elif; Cetinkaya, Semra; Aycan, Zehra

    2014-01-01

    Insulin autoimmune syndrome (IAS) is a condition characterized by hypoglycemia associated with the presence of autoantibodies to insulin in patients who have not been injected with insulin. A female patient (aged 16 years and 3 months) presented with the complaint of being overweight. Physical examination revealed a body weight of 78.2 kg (+2.6 SD) and a height of 167 cm (+0.73 SD). While the patient's fasting blood glucose level was found to be 40 mg/dl, blood ketone was negative and the serum insulin level was determined as 379 mIU/ml. The patient was diagnosed with hyperinsulinemic hypoglycemia. Abdominal ultrasound, pancreas MRI and endoscopic ultrasound were normal. The daily blood glucose profile revealed postprandial hyperglycemia and reactive hypoglycemia in addition to fasting hypoglycemia. The results of anti-insulin antibody measurements were as high as 41.8% (normal range 0-7%). A 1,600-calorie diet containing 40% carbohydrate and divided into 6 meals a day was given to the patient. Simple sugars were excluded from the diet. Hypoglycemic episodes were not observed, but during 2 years of observation, serum levels of insulin and anti-insulin antibodies remained elevated. In all hyperinsulinemic hypoglycemia cases, IAS should be considered in the differential diagnosis and insulin antibody measurements should be carried out. © 2014 S. Karger AG, Basel.

  13. Endocrine determinants of changes in insulin sensitivity and insulin secretion during a weight cycle in healthy men.

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    Judith Karschin

    Full Text Available Changes in insulin sensitivity (IS and insulin secretion occur with perturbations in energy balance and glycemic load (GL of the diet that may precede the development of insulin resistance and hyperinsulinemia. Determinants of changes in IS and insulin secretion with weight cycling in non-obese healthy subjects remain unclear.In a 6wk controlled 2-stage randomized dietary intervention 32 healthy men (26±4y, BMI: 24±2kg/m2 followed 1wk of overfeeding (OF, 3wks of caloric restriction (CR containing either 50% or 65% carbohydrate (CHO and 2wks of refeeding (RF with the same amount of CHO but either low or high glycaemic index at ±50% energy requirement. Measures of IS (basal: HOMA-index, postprandial: Matsuda-ISI, insulin secretion (early: Stumvoll-index, total: tAUC-insulin/tAUC-glucose and potential endocrine determinants (ghrelin, leptin, adiponectin, thyroid hormone levels, 24h-urinary catecholamine excretion were assessed.IS improved and insulin secretion decreased due to CR and normalized upon RF. Weight loss-induced improvements in basal and postprandial IS were associated with decreases in leptin and increases in ghrelin levels, respectively (r = 0.36 and r = 0.62, p<0.05. Weight regain-induced decrease in postprandial IS correlated with increases in adiponectin, fT3, TSH, GL of the diet and a decrease in ghrelin levels (r-values between -0.40 and 0.83, p<0.05 whereas increases in early and total insulin secretion were associated with a decrease in leptin/adiponectin-ratio (r = -0.52 and r = -0.46, p<0.05 and a decrease in fT4 (r = -0.38, p<0.05 for total insulin secretion only. After controlling for GL associations between RF-induced decrease in postprandial IS and increases in fT3 and TSH levels were no longer significant.Weight cycling induced changes in IS and insulin secretion were associated with changes in all measured hormones, except for catecholamine excretion. While leptin, adiponectin and ghrelin seem to be the major

  14. Relationship between increased serum tumor necrosis factor levels and insulin resistance in patients with essential hypertension

    International Nuclear Information System (INIS)

    Wang Weimin; Li Jinliang; Huang Yongqiang

    2010-01-01

    Objective: To investigate the relationship between serum tumor necrosis factor-α (TNF-α) levels and insulin resistance (IR) in patients with essential by pertension. Methods: Serum TNF-α and free insulin (fINS)levels were measured with RIA in 41 patients with essential hypertension and 38 controls. Insulin resistance was calculated with insulin resistance index (HOMA-IR). Results: The serum TNF-α levels were significantly higher in patients with essential hypertension than those in the controls (P<0.001). The HOMA-IR was also significantly higher in hypertension group than that in controls (P<0.001). Serum TNF-α levels was positively correlated with BMI, HOMA-IR and SBP both in hypertension group and control group (P<0.05). Conclusion: Serum TNF-α level was increased in hypertensive patients and positively correlated with obesity and IR. (authors)

  15. Long-term exposure to abnormal glucose levels alters drug metabolism pathways and insulin sensitivity in primary human hepatocytes

    Science.gov (United States)

    Davidson, Matthew D.; Ballinger, Kimberly R.; Khetani, Salman R.

    2016-06-01

    Hyperglycemia in type 2 diabetes mellitus has been linked to non-alcoholic fatty liver disease, which can progress to inflammation, fibrosis/cirrhosis, and hepatocellular carcinoma. Understanding how chronic hyperglycemia affects primary human hepatocytes (PHHs) can facilitate the development of therapeutics for these diseases. Conversely, elucidating the effects of hypoglycemia on PHHs may provide insights into how the liver adapts to fasting, adverse diabetes drug reactions, and cancer. In contrast to declining PHH monocultures, micropatterned co-cultures (MPCCs) of PHHs and 3T3-J2 murine embryonic fibroblasts maintain insulin-sensitive glucose metabolism for several weeks. Here, we exposed MPCCs to hypo-, normo- and hyperglycemic culture media for ~3 weeks. While albumin and urea secretion were not affected by glucose level, hypoglycemic MPCCs upregulated CYP3A4 enzyme activity as compared to other glycemic states. In contrast, hyperglycemic MPCCs displayed significant hepatic lipid accumulation in the presence of insulin, while also showing decreased sensitivity to insulin-mediated inhibition of glucose output relative to a normoglycemic control. In conclusion, we show for the first time that PHHs exposed to hypo- and hyperglycemia can remain highly functional, but display increased CYP3A4 activity and selective insulin resistance, respectively. In the future, MPCCs under glycemic states can aid in novel drug discovery and mechanistic investigations.

  16. Insulin and C peptide response, and antibody levels in hepatitis C related chronic liver disease

    International Nuclear Information System (INIS)

    Abbas, Z.; Tariq, N.; Iqbal, M.; Shah, M.A.

    2002-01-01

    Objective: Patients with cirrhosis due to hepatitis C (HC) have an increased prevalence of diabetes mellitus. The pathogenic mechanism by which HC predisposes to DM is not clear. The objective of this study was to determine the insulin and C-peptide response to 75 gram oral glucose load and measure anti phospholipid antibody levels in patients with chronic liver disease due to HC. Design: a prospective study. Place and duration of study: This study was conducted at the department of medicine, Jinnah postgraduate medical centre over period of three months. Subjects and methods: An analytical case control study was carried out on 37 patients (m-18,f=19); none of these patients had received interferon. They were divided into four groups: (a) HC cirrhosis with DM (n=9 ), (b) HC cirrhosis without DM (n=11), (c) hepatitis B (HB) cirrhosis without DM (n=7), (d) chronic hepatitis C without DM (n=10). Group C and D were taken as controls. Fasting blood samples were taken and repeated after 2 hours of 75 gram oral glucose load (2 h PG). Result: mean ages of group A,B,C and D were (yr +- SD) 51.3 +- 7.6,48.9 +- 2.4, 33.7 +-10.8 and 31.7 +- 8.8 respectively. There was no statistically significant difference in the age, Pugh score and body mass index of HC cirrhotic patients with and without DM. Patients of group A had higher fasting and 2 h PG glucose levels (P=0.003 and 0.000) and higher fasting insulin level (p=0.045). However, increments in insulin and c peptide levels 2 h PG were much less (p=0.048 and 0.003). HB cirrhotics without diabetes (group C behaved just like HC cirrhotic without diabetes (group B). Patients of group D had normal glucose tolerance and insulin and C peptide levels. All four groups had normal anti phospholipid antibody levels. Conclusion: Patients with cirrhosis due to HC nd HB show evidence of glucose intolerance in spite of hyperinsulinaemia probably due to insulin resistance. HC cirrhotics with diabetes have fasting hyperglycemia in spite of

  17. Insulin signaling regulates fatty acid catabolism at the level of CoA activation.

    Directory of Open Access Journals (Sweden)

    Xiaojun Xu

    2012-01-01

    Full Text Available The insulin/IGF signaling pathway is a highly conserved regulator of metabolism in flies and mammals, regulating multiple physiological functions including lipid metabolism. Although insulin signaling is known to regulate the activity of a number of enzymes in metabolic pathways, a comprehensive understanding of how the insulin signaling pathway regulates metabolic pathways is still lacking. Accepted knowledge suggests the key regulated step in triglyceride (TAG catabolism is the release of fatty acids from TAG via the action of lipases. We show here that an additional, important regulated step is the activation of fatty acids for beta-oxidation via Acyl Co-A synthetases (ACS. We identify pudgy as an ACS that is transcriptionally regulated by direct FOXO action in Drosophila. Increasing or reducing pudgy expression in vivo causes a decrease or increase in organismal TAG levels respectively, indicating that pudgy expression levels are important for proper lipid homeostasis. We show that multiple ACSs are also transcriptionally regulated by insulin signaling in mammalian cells. In sum, we identify fatty acid activation onto CoA as an important, regulated step in triglyceride catabolism, and we identify a mechanistic link through which insulin regulates lipid homeostasis.

  18. Dietary leucine--an environmental modifier of insulin resistance acting on multiple levels of metabolism.

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    Yazmin Macotela

    Full Text Available Environmental factors, such as the macronutrient composition of the diet, can have a profound impact on risk of diabetes and metabolic syndrome. In the present study we demonstrate how a single, simple dietary factor--leucine--can modify insulin resistance by acting on multiple tissues and at multiple levels of metabolism. Mice were placed on a normal or high fat diet (HFD. Dietary leucine was doubled by addition to the drinking water. mRNA, protein and complete metabolomic profiles were assessed in the major insulin sensitive tissues and serum, and correlated with changes in glucose homeostasis and insulin signaling. After 8 weeks on HFD, mice developed obesity, fatty liver, inflammatory changes in adipose tissue and insulin resistance at the level of IRS-1 phosphorylation, as well as alterations in metabolomic profile of amino acid metabolites, TCA cycle intermediates, glucose and cholesterol metabolites, and fatty acids in liver, muscle, fat and serum. Doubling dietary leucine reversed many of the metabolite abnormalities and caused a marked improvement in glucose tolerance and insulin signaling without altering food intake or weight gain. Increased dietary leucine was also associated with a decrease in hepatic steatosis and a decrease in inflammation in adipose tissue. These changes occurred despite an increase in insulin-stimulated phosphorylation of p70S6 kinase indicating enhanced activation of mTOR, a phenomenon normally associated with insulin resistance. These data indicate that modest changes in a single environmental/nutrient factor can modify multiple metabolic and signaling pathways and modify HFD induced metabolic syndrome by acting at a systemic level on multiple tissues. These data also suggest that increasing dietary leucine may provide an adjunct in the management of obesity-related insulin resistance.

  19. The rs1862513 Variant in Resistin Gene-Modified Insulin Resistance and Insulin Levels after Weight Loss Secondary to Hypocaloric Diet.

    Science.gov (United States)

    de Luis, Daniel Antonio; Izaola, Olatz; Primo, David; de la Fuente, Beatriz; Mulero, Ines; Aller, Rocío

    2016-01-01

    Polymorphisms of a single nucleotide in RETN have been associated with indexes of insulin resistance. Our aim was to analyze the effects of the rs1862513 RETN gene polymorphism on insulin resistance, insulin levels, and resistin levels changes after 3 months of a low-fat hypocaloric diet. A Caucasian population of 133 obese patients was analyzed before and after 3 months on a low-fat hypocaloric diet. Fifty-six patients (42.1%) had the genotype GG (wild group) and 77 (57.9%) patients had the other genotypes; GC (59 patients, 44.4%) or CC (18 patients, 13.5%; mutant group). In wild and mutant genotype groups, weight, body mass index, fat mass, waist circumference, and systolic blood pressure decreased. In the wild genotype group, the decrease in total cholesterol was -13.1 ± 25.3 mg/dL (vs. -4.4 ± 13.7 mg/dL in mutant group: p = 0.004 for group deltas), low density lipoprotein (LDL)-cholesterol was -13.0 ± 21.5 mg/dL (-4.3 ± 10.5 mg/dL: p = 0.007), glucose -7.2 ± 3.5 mg/dL (-0.8 ± 0.2 mg/dL: p = 0.01), insulin -5.6 ± 2.5 mUI/L (-2.9 ± 1.2 mUI/L: p = 0.03) and homeostasis model assessment-insulin resistance (HOMA-IR) -2.5 ± 1.1 (-0.6 ± 1.4: p = 0.02). Leptin levels decreased in both genotypes (-10.1 ± 9.5 ng/dL in wild type group vs. -13.1 ± 0.2 ng/dL in mutant type group: p > 0.05). The present study suggests that the G/G genotype of RETN rs1862513 could be a predictor of the reduction of HOMA-IR, insulin, fasting glucose and LDL cholesterol secondary to a hypocaloric diet in obese subjects. © 2016 S. Karger AG, Basel.

  20. Changes in Insulin-like Growth Factor-1 Level in Patients with Sepsis and Septic Shock

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    Sang Hoon Lee

    2016-11-01

    Full Text Available Background Despite many ongoing, prospective studies on the topic, sepsis still remains one of the main causes of death in hospital. The hormone insulin-like growth factor 1 (IGF-1 has a similar molecular structure to that of insulin. IGF-1 exerts anabolic effects and plays important roles in both normal physiology and pathologic processes. Previous studies have observed low serum IGF-1 level in patients with critical illnesses. Here, we evaluated changes in IGF-1 level based on survival of septic patients. Methods We evaluated 140 patients with sepsis and septic shock (21 with sepsis and 119 with septic shock admitted to the intensive care unit of a university-affiliated hospital in Korea. Serum IGF-1 level was measured on days 0, 1, 3, and 7. Patients with liver disease were excluded from this study. All data were analyzed using SPSS version 20 (SPSS Inc., Chicago, IL, USA. Results Patients with septic shock had significantly lower serum IGF-1 level on days 1 and 3 than patients without septic shock (p = 0.002 and p = 0.007, respectively. Generally, there was a negative relationship between IGF-1 and serum cortisol levels; however, this relationship was only significant on day 3 (p = 0.029. Furthermore, renin showed significantly negative correlation with IGF-1 on day 3 (p = 0.038. IGF-1 level did not show significant difference between survivors and non-survivors. Conclusions Our results showed that IGF-1 was associated with septic shock, and that the IGF-1 axis is severely disrupted in septic patients. Additionally, serum cortisol and renin levels were associated with IGF-1 level.

  1. Serum progranulin levels in relation to insulin resistance in childhood obesity.

    Science.gov (United States)

    Alissa, Eman M; Sutaih, Rima H; Kamfar, Hayat Z; Alagha, Abdulmoeen E; Marzouki, Zuhair M

    2017-11-27

    Progranulin is an adipokine that is involved in the inflammatory response, glucose metabolism, insulin resistance, and may therefore be involved in chronic subclinical inflammation associated with the pathogenesis of childhood obesity. We aimed to investigate the association of circulating progranulin levels with metabolic parameters in children and to assess the importance of progranulin as a biomarker for metabolic diseases. A total of 150 children were consecutively recruited from the Pediatric Nutrition Clinics at King Abdulaziz University Hospital in Jeddah, Saudi Arabia. Children were classified into four groups based on quartile for serum progranulin. Anthropometric variables were measured in all study subjects. Fasting blood samples were collected for measurement of blood glucose, insulin and lipid profile. Children within the upper quartile for serum progranulin concentration were heavier, more insulin resistant and had higher concentrations of serum total cholesterol, triglycerides, insulin and high sensitivity C reactive protein compared to those in the lower quartile. On correlation analysis, serum progranulin concentrations were significantly related to general and central adiposity, metabolic parameters, markers of inflammation and insulin resistance. Stepwise multiple regression showed that 26.6% of the variability in serum progranulin could be explained by measures of adiposity. The increased serum progranulin concentrations were closely related to measures of adiposity, metabolic parameters, inflammatory marker and insulin resistance indices, suggesting that progranulin may be an excellent biomarker for obesity in childhood.

  2. Increased androgen levels in rats impair glucose-stimulated insulin secretion through disruption of pancreatic beta cell mitochondrial function.

    Science.gov (United States)

    Wang, Hongdong; Wang, Xiaping; Zhu, Yunxia; Chen, Fang; Sun, Yujie; Han, Xiao

    2015-11-01

    Although insulin resistance is recognized to contribute to the reproductive and metabolic phenotypes of polycystic ovary syndrome (PCOS), pancreatic beta cell dysfunction plays an essential role in the progression from PCOS to the development of type 2 diabetes. However, the role of insulin secretory abnormalities in PCOS has received little attention. In addition, the precise changes in beta cells and the underlying mechanisms remain unclear. In this study, we therefore attempted to elucidate potential mechanisms involved in beta cell alterations in a rat model of PCOS. Glucose-induced insulin secretion was measured in islets isolated from DHT-treated and control rats. Oxygen consumption rate (OCR), ATP production, and mitochondrial copy number were assayed to evaluate mitochondrial function. Glucose-stimulated insulin secretion is significantly decreased in islets from DHT-treated rats. On the other hand, significant reductions are observed in the expression levels of several key genes involved in mitochondrial biogenesis and in mitochondrial OCR and ATP production in DHT-treated rat islets. Meanwhile, we found that androgens can directly impair beta cell function by inducing mitochondrial dysfunction in vitro in an androgen receptor dependent manner. For the first time, our study demonstrates that increased androgens in female rats can impair glucose-stimulated insulin secretion partly through disruption of pancreatic beta cell mitochondrial function. This work has significance for hyperandrogenic women with PCOS: excess activation of the androgen receptor by androgens may provoke beta cell dysfunction via mitochondrial dysfunction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Effect of glibenclamide on insulin release at moderate and high blood glucose levels in normal man

    NARCIS (Netherlands)

    Ligtenberg, JJM; Venker, CE; Sluiter, WJ; VanHaeften, TW

    Insulin release occurs in two phases; sulphonylurea derivatives may have different potencies in stimulating first-and second-phase insulin release. We studied the effect of glibenclamide on insulin secretion at submaximally and maximally stimulating blood glucose levels with a primed hyperglycaemic

  4. Reduced levels of SCD1 accentuate palmitate-induced stress in insulin-producing β-cells

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    Hovsepyan Meri

    2010-09-01

    Full Text Available Abstract Background Stearoyl-CoA desaturase 1 (SCD1 is an ER resident enzyme introducing a double-bond in saturated fatty acids. Global knockout of SCD1 in mouse increases fatty acid oxidation and insulin sensitivity which makes the animal resistant to diet-induced obesity. Inhibition of SCD1 has therefore been proposed as a potential therapy of the metabolic syndrome. Much of the work has focused on insulin target tissue and very little is known about how reduced levels of SCD1 would affect the insulin-producing β-cell, however. The aim of the present study was therefore to investigate how reduced levels of SCD1 affect the β-cell. Results Insulin-secreting MIN6 cells with reduced levels of SCD1 were established by siRNA mediated knockdown. When fatty acid oxidation was measured, no difference between cells with reduced levels of SCD1 and mock-transfected cells were found. Also, reducing levels of SCD1 did not affect insulin secretion in response to glucose. To investigate how SCD1 knockdown affected cellular mechanisms, differentially regulated proteins were identified by a proteomic approach. Cells with reduced levels of SCD1 had higher levels of ER chaperones and components of the proteasome. The higher amounts did not protect the β-cell from palmitate-induced ER stress and apoptosis. Instead, rise in levels of p-eIF2α and CHOP after palmitate exposure was 2-fold higher in cells with reduced levels of SCD1 compared to mock-transfected cells. Accordingly, apoptosis rose to higher levels after exposure to palmitate in cells with reduced levels of SCD1 compared to mock-transfected cells. Conclusions In conclusion, reduced levels of SCD1 augment palmitate-induced ER stress and apoptosis in the β-cell, which is an important caveat when considering targeting this enzyme as a treatment of the metabolic syndrome.

  5. The Role of Insulin Therapy in Correcting Hepcidin Levels in Patients with Type 2 Diabetes Mellitus

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    Driton Vela

    2017-05-01

    Full Text Available Objectives: Iron overload can cause or contribute to the pathogenesis of type 2 diabetes mellitus (T2DM, but how the major parameters of iron metabolism change in different settings of diabetes are still unclear. The aim of this study was to determine the relationship between iron, ferritin, and hepcidin levels in diabetic patients and the effect of insulin treatment. Methods: The study included 80 subjects, 60 with T2DM and 20 without (control group. Serum hepcidin, insulin, ferritin, and iron levels were determined as well as other clinical parameters. The associations between these parameters were analyzed between both groups. Results: Hepcidin levels expressed as mean± standard deviation between groups showed no significant changes (14.4±6.7 ng/mL for the control group, and 18.4±7.9 ng/mL for patients with diabetes, p = 0.069. Parameters of iron metabolism showed modest correlation with the parameters of glucose metabolism. However, the correlation between ferritin and insulin in both groups was statistically significant (p = 0.032; ρ = 0.480 vs. p = 0.011; ρ = 0.328. Conclusions: Our study showed that hepcidin levels in patients with T2DM on insulin therapy do not change, which might be a result of treatment with insulin. In this context, insulin treatment can be used as a novel method for correction of hepcidin levels. By correcting hepcidin levels, we can prevent cellular iron overload and reduce the risk of diabetes.

  6. Effects of supervised structured aerobic exercise training program on fasting blood glucose level, plasma insulin level, glycemic control, and insulin resistance in type 2 diabetes mellitus.

    Science.gov (United States)

    Shakil-Ur-Rehman, Syed; Karimi, Hossein; Gillani, Syed Amir

    2017-01-01

    To determine the effects of supervised structured aerobic exercise training (SSAET) program on fasting blood glucose level (FBGL), plasma insulin level (PIL), glycemic control (GC), and insulin resistance (IR) in type 2 diabetes mellitus (T2DM). Riphah Rehabilitation and Research Centre (RRRC) was the clinical setting for this randomized controlled trial, located at Pakistan Railways General Hospital (PRGH), Rawalpindi, Pakistan. Study duration was 18 months from January 1, 2015 to June 30, 2016. Patients of both genders ranging 40-70 years of age with at least one year of history of T2DM were considered eligible according to WHO criteria, while patients with other chronic diseases, history of smoking, regular exercise and diet plan were excluded. Cohorts of 195 patients were screened out of whom 120 fulfilled the inclusion criteria. Amongst them 102 agreed to participate and were assigned to experimental (n=51) and control (n=51) groups. Experimental group underwent SSAET program, routine medication and dietary plan, whereas the control group received routine medication and dietary plan, while both group received treatment for 25 weeks. The blood samples were taken at baseline and on the completion of 25 weeks. The investigation of fasting blood glucose level, plasma insulin level, and glycemic control was conducted to calculate IR. Patients with T2DM in experimental group (n=51) treated with SSAET program, routine medication and dietary plan significantly improved FBGL (pre-mean= 276.41±25.31, post-mean=250.07±28.23), PIL (pre-mean=13.66±5.31, post-mean=8.91±3.83), GC (pre-mean=8.31±1.79, post-mean 7.28±1.43), and IR (pre-mean=64.95±27.26, post-mean 37.97±15.58), as compared with patients in control group treated with routine medication and dietary plan in whom deteriorations were noted in FBGL (pre-mean=268.19±22.48, post-mean=281.41±31.30), PIL(pre-mean=14.14±5.48, post-mean=14.85±5.27) GC (pre-mean=8.15±1.74, post-mean=8.20±1.44, and IR (pre

  7. Partial ablation of adult Drosophila insulin-producing neurons modulates glucose homeostasis and extends life span without insulin resistance.

    Science.gov (United States)

    Haselton, Aaron; Sharmin, Effat; Schrader, Janel; Sah, Megha; Poon, Peter; Fridell, Yih-Woei C

    2010-08-01

    In Drosophila melanogaster (D. melanogaster), neurosecretory insulin-like peptide-producing cells (IPCs), analogous to mammalian pancreatic beta cells are involved in glucose homeostasis. Extending those findings, we have developed in the adult fly an oral glucose tolerance test and demonstrated that IPCs indeed are responsible for executing an acute glucose clearance response. To further develop D. melanogaster as a relevant system for studying age-associated metabolic disorders, we set out to determine the impact of adult-specific partial ablation of IPCs (IPC knockdown) on insulin-like peptide (ILP) action, metabolic outcomes and longevity. Interestingly, while IPC knockdown flies are hyperglycemic and glucose intolerant, these flies remain insulin sensitive as measured by peripheral glucose disposal upon insulin injection and serine phosphorylation of a key insulin-signaling molecule, Akt. Significant increases in stored glycogen and triglyceride levels as well as an elevated level of circulating lipid measured in adult IPC knockdown flies suggest profound modulation in energy metabolism. Additional physiological outcomes measured in those flies include increased resistance to starvation and impaired female fecundity. Finally, increased life span and decreased mortality rates measured in IPC knockdown flies demonstrate that it is possible to modulate ILP action in adult flies to achieve life span extension without insulin resistance. Taken together, we have established and validated an invertebrate genetic system to further investigate insulin action, metabolic homeostasis and regulation of aging regulated by adult IPCs.

  8. Reduction of lns-1 gene expression and tissue insulin levels in n5-STZ rats

    Directory of Open Access Journals (Sweden)

    Belinda Vargas Guerrero

    2013-01-01

    Full Text Available Objective: The high global incidence of type 2 diabetes has challenged researchers to establish animal models that resemble the chronic stage observed in type 2 diabetes patients. One such model is induced by neonatal streptozotocin (n-STZ administration to rat pups at 0, 2, or 5 days after birth. In this study, we assessed lns-1 gene expression and tissue insulin levels as well as serum concentration of glucose and insulin, insulin resistance, and histological changes of the islets of Langerhans in n5-STZ rats after 20-weeks post-induction. Methods: Wistar rat pups were randomly distributed into a control group and a streptozotocin-induced group. Experimental induction involved a single intraperitoneal injection of streptozotocin (150 mg/kg into neonates at five days after birth. Results: At 20 weeks post-induction, streptozotocin-induced rats exhibited increased serum glucose levels, reduced serum insulin levels, impaired glucose metabolism and insulin resistance compared to control rats. Histologically, streptozotocin-induced rats exhibited atrophic islets, vacuolization, and significantly fewer insulin-positive cells. lns-1 gene expression was significantly decreased in n5-STZ rats in comparison to the control group. Conclusion: Our findings support that the n5-STZ model 20 weeks post-induction represents an appropriate experimental tool to study T2D and to evaluate novel therapeutic agents and targets that involve insulin gene expression and secretion, as well as complications caused by chronic diabetes.

  9. The Emerging Role of Branched-Chain Amino Acids in Insulin Resistance and Metabolism

    OpenAIRE

    Yoon, Mee-Sup

    2016-01-01

    Insulin is required for maintenance of glucose homeostasis. Despite the importance of insulin sensitivity to metabolic health, the mechanisms that induce insulin resistance remain unclear. Branched-chain amino acids (BCAAs) belong to the essential amino acids, which are both direct and indirect nutrient signals. Even though BCAAs have been reported to improve metabolic health, an increased BCAA plasma level is associated with a high risk of metabolic disorder and future insulin resistance, or...

  10. Insulin Resistance and Increased Muscle Cytokine Levels in Patients With Mitochondrial Myopathy

    DEFF Research Database (Denmark)

    Rue, Nana; Vissing, John; Galbo, Henrik

    2014-01-01

    CONTEXT: Mitochondrial dysfunction has been proposed to cause insulin resistance and that might stimulate cytokine production. OBJECTIVE: The objective of the study was to elucidate the association between mitochondrial myopathy, insulin sensitivity, and cytokine levels in muscle. DESIGN......: The intervention included a 120-minute hyperinsulinemic, euglycemic clamp. Another morning, microdialysis of both vastus lateralis muscles for 4 hours, including one-legged, knee extension exercise for 30 minutes, was performed. MAIN OUTCOME MEASURES: Glucose infusion rate during 90-120 minutes of insulin infusion...... was measured. Cytokine concentrations in dialysate were also measured. RESULTS: Muscle strength, percentage fat mass, and creatine kinase in plasma did not differ between groups. The maximal oxygen uptake was 21 ± 3 (SE) (P) and 36 ± 3(C) mL/kg·min (2P insulin, C-peptide, and glucagon were higher...

  11. The influence of short-term endurance training on the insulin blood level, binding, and degradation of 125I-insulin by erythrocyte receptors in patients after myocardial infarction.

    Science.gov (United States)

    Dylewicz, P; Przywarska, I; Szcześniak, L; Rychlewski, T; Bieńkowska, S; Długiewicz, I; Wilk, M

    1999-01-01

    This study was directed toward establishing whether and to what extent, short-term endurance training influences the insulin blood level, and the binding and degradation of 125I-insulin by erythrocyte receptors in patients undergoing rehabilitation after myocardial infarction. The study was conducted in a group of 60 patients who had had myocardial infarction within the past 1.5 to 3 months and who did not have arterial hypertension and diabetes mellitus. All the patients took a symptom-limited cardiopulmonary exercise test. Before and after the test, venous blood was collected to determine lactic acid and insulin blood levels as well as the binding and degradation of 125I-insulin. The study group was randomized into two subgroups. One subgroup entered into a 3-week in-patient rehabilitation course. The control group was discharged from the hospital and was given no recommendations for physical exercise. The same investigation was repeated 3 weeks later. In the patients (50%) with hyperinsulinemia (insulin resistance index, > 10 microIU/mL), which was detected during the first investigation, insulin blood level decreased from 23.9 +/- 4.4 to 15.0 +/- 1.9 microIU/mL (P endurance training period during rehabilitation after myocardial infarction reduces insulin resistance in patients with hyperinsulinemia.

  12. Serum insulin-like factor 3 levels during puberty in healthy boys and boys with Klinefelter syndrome

    DEFF Research Database (Denmark)

    Wikström, Anne M; Bay, Katrine; Hero, Matti

    2006-01-01

    Levels of the Leydig cell-specific hormone insulin-like factor 3 (INSL3) are incompletely characterized in boys during pubertal development.......Levels of the Leydig cell-specific hormone insulin-like factor 3 (INSL3) are incompletely characterized in boys during pubertal development....

  13. Association between Myeloperoxidase Levels and Risk of Insulin Resistance in Egyptian Obese Women

    Science.gov (United States)

    Zaki, Moushira; Basha, Walaa; Reyad, Hanaa; Mohamed, Ramy; Hassan, Naglaa; Kholousi, Shams

    2018-01-01

    BACKGROUND: Myeloperoxidase (MPO) is an enzyme involved in the pathogenesis of several diseases. AIM: The current study aimed to investigate serum MPO levels in obese Egyptian women and assess its relation with insulin resistance (IR) and other biochemical risk parameters. METHODS: The study included 80 obese women and 50 age-and-sex-matched healthy controls. Insulin resistance (IR) was evaluated by the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR). Serum MPO, fasting glucose, insulin and blood lipids and anthropometry were measured. Obese cases were divided into three groups based on MPO tertiles. ROC analysis was performed to obtain the optimal cut-off values of MPO to predicate IR in obese women. RESULTS: The mean serum MPO was significantly higher in obese cases than controls. Cases in the highest MPO tertile had higher HOMA-IR, blood lipids and pressure levels compared with those in the lower tertile. The cutoff point of MPO was > 87.8 (ng/mL) and area under curves was 0.82 (p < 0.01) for diagnosis of IR. MPO levels were higher in obese Egyptian women than healthy controls. CONCLUSION: Elevation of MPO was associated with abnormal metabolic parameters. MPO might be used as an earlier biomarker for IR and metabolic disturbance in obese women. PMID:29731928

  14. Effects of dietary carbohydrate sources on plasma glucose, insulin and IGF-I levels in multiparous sows

    NARCIS (Netherlands)

    Wientjes, J.G.M.; Soede, N.M.; Aarsse, F.; Laurenssen, B.F.A.; Koopmanschap, R.E.; Brand, van den H.; Kemp, B.

    2012-01-01

    Effects of different carbohydrate sources on plasma glucose, insulin and insulin-like growth factor-I (IGF-I) levels were compared to subsequently be able to study effects of insulin-stimulating diets on follicle development in sows. The following feed components were tested in 12 sows during six

  15. [Plasma IL-18 levels are related to insulin and are modulated by IL-18 gene polymorphisms].

    Science.gov (United States)

    Martinez-Hervas, Sergio; Martínez-Barquero, Vanesa; Nuñez Savall, Ester; Lendínez, Verónica; Olivares, Laura; Benito, Esther; Real, Jose T; Chaves, F Javier; Ascaso, Juan F

    2015-01-01

    Atherosclerosis is an inflammatory chronic disease influenced by multiple factors. Different prospective studies have shown that plasmatic levels of inflammatory markers were related to atherosclerosis and cardiovascular disease. To evaluate whether plasmatic levels of interleukin 18 (IL-18) are modulated by SNPs (single nucleotide polymorphisms) of the IL 18 gene and its possible association with insulin levels and other cardiovascular risk factors. 746 individuals were studied for a period of two years by opportunistic selection in the metropolitan area of Valencia. Parameters of lipid and glucose metabolism were analyzed by standard methodology. IL-18 was measured by ELISA. Individuals with insulin resistance showed significant higher levels of IL-18. IL 18 was significantly correlated with insulin levels and other cardiovascular risk factors. The CC genotype of the rs1834481 SNP was significantly associated with lower levels of IL-18. However, the GG genotype of the rs7559479 was associated with significant higher levels of IL-18. IL-18 is associated with insulin resistance and other cardiovascular risk factors, being those levels genetically regulated. Copyright © 2015 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  16. TNFα dynamics during the oral glucose tolerance test vary according to the level of insulin resistance in pregnant women.

    Science.gov (United States)

    Guillemette, Laetitia; Lacroix, Marilyn; Battista, Marie-Claude; Doyon, Myriam; Moreau, Julie; Ménard, Julie; Ardilouze, Jean-Luc; Perron, Patrice; Hivert, Marie-France

    2014-05-01

    TNFα is suspected to play a role in inflammation and insulin resistance leading to higher risk of metabolic impairment. Controversies exist concerning the role of TNFα in gestational insulin resistance. We investigated the interrelations between TNFα and insulin resistance in a large population-based cohort of pregnant women. Women (n = 756) were followed prospectively at 5-16 weeks and 24-28 weeks of pregnancy. Anthropometric measures and blood samples were collected at both visits. A 75-g oral glucose tolerance test (OGTT) was conducted at the second trimester to assess insulin sensitivity status (homeostasis model of assessment of insulin resistance and Matsuda index). TNFα was measured at the first trimester (nonfasting) and at each time point of the OGTT. Participants were 28.4 ± 4.4 years old and had a mean body mass index of 25.5 ± 5.5 kg/m(2) at first trimester. Median TNFα levels were 1.56 (interquartile range, 1.18-2.06) pg/mL at first trimester and 1.61 (interquartile range, 1.12-2.13) pg/mL at second trimester (1 h after glucose load). At second trimester, higher TNFα levels were associated with higher insulin resistance index levels (r = 0.37 and -0.30 for homeostasis model of assessment of insulin resistance and Matsuda index, respectively; P insulin resistance showed a continuing decrease in TNFα levels during the OGTT, whereas women who were more insulin sensitive showed an increase in TNFα at hour 1 and a decrease at hour 2 of the test. Higher insulin resistance is associated with higher levels of circulating TNFα at first and second trimesters of pregnancy. TNFα level dynamics during an OGTT at second trimester vary according to insulin-resistance state.

  17. Neural correlates of stress- and food cue-induced food craving in obesity: association with insulin levels.

    Science.gov (United States)

    Jastreboff, Ania M; Sinha, Rajita; Lacadie, Cheryl; Small, Dana M; Sherwin, Robert S; Potenza, Marc N

    2013-02-01

    Obesity is associated with alterations in corticolimbic-striatal brain regions involved in food motivation and reward. Stress and the presence of food cues may each motivate eating and engage corticolimibic-striatal neurocircuitry. It is unknown how these factors interact to influence brain responses and whether these interactions are influenced by obesity, insulin levels, and insulin sensitivity. We hypothesized that obese individuals would show greater responses in corticolimbic-striatal neurocircuitry after exposure to stress and food cues and that brain activations would correlate with subjective food craving, insulin levels, and HOMA-IR. Fasting insulin levels were assessed in obese and lean subjects who were exposed to individualized stress and favorite-food cues during functional MRI. Obese, but not lean, individuals exhibited increased activation in striatal, insular, and hypothalamic regions during exposure to favorite-food and stress cues. In obese but not lean individuals, food craving, insulin, and HOMA-IR levels correlated positively with neural activity in corticolimbic-striatal brain regions during favorite-food and stress cues. The relationship between insulin resistance and food craving in obese individuals was mediated by activity in motivation-reward regions including the striatum, insula, and thalamus. These findings demonstrate that obese, but not lean, individuals exhibit increased corticolimbic-striatal activation in response to favorite-food and stress cues and that these brain responses mediate the relationship between HOMA-IR and food craving. Improving insulin sensitivity and in turn reducing corticolimbic-striatal reactivity to food cues and stress may diminish food craving and affect eating behavior in obesity.

  18. Association of Tumor Growth Factor-? and Interferon-? Serum Levels with Insulin Resistance in Normal Pregnancy

    OpenAIRE

    Jahromi, Abdolreza Sotoodeh; Sanie, Mohammad Sadegh; Yusefi, Alireza; Zabetian, Hassan; Zareian, Parvin; Hakimelahi, Hossein; Madani, Abdolhossien; Hojjat-Farsangi, Mohammad

    2015-01-01

    Pregnancy is related to change in glucose metabolism and insulin production. The aim of our study was to determine the association of serum IFN-? and TGF-? levels with insulin resistance during normal pregnancy. This cross sectional study was carried out on 97 healthy pregnant (in different trimesters) and 28 healthy non-pregnant women. Serum TGF-? and IFN-? level were measured by ELISA method. Pregnant women had high level TGF-? and low level IFN-? as compared non-pregnant women. Maternal se...

  19. The Effect of Two Acute Eccentric and Concentric Exercises on Serum Irisin Level and Insulin Resistance Index in Inactive Obese Women

    Directory of Open Access Journals (Sweden)

    Faranak Balaghi Inaloo

    2016-12-01

    Full Text Available Abstract Background: Recently a myokine named irisin has been discovered that effects on obesity, metabolism and glucose homeostasis through browning white adipose tissue and thermogenesis. However, the effects of type and intensity of exercises on it have remained unclear. The purpose of this study was to evaluate the effects of two acute eccentric and concentric exercises on serum irisin level and insulin resistance in obese sedentary women. Materials and Methods: The study was quasi-experimental. 15 female students with a body mass index above 30 kg/m2 and mean age 24.86±2.87 years participated in the study. After measuring the maximal uptake oxygen of participants, they did two acute eccentric and concentric exercises using treadmill in a cross-over design within 10 days. After at least 8 hours- fasting, blood samples were collected before and immediately after each activity, to measure the levels of irisin, glucose and insulin. Data were analyzed using paired t-test and repeated measures ANOVA. In addition, Pearson correlation was used to examine the relationship between variables. Results: the irisin levels increased significantly after both types of exercises (p<0.05, that this increase in concentric activity was more than eccentric activity. Insulin resistance increased immediately after both exercises as well, that this increase in concentric exercise was statistically significant (p<0.05. Conclusion: However, both eccentric and concentric exercises had no effect on improving insulin resistance in obese women, but they can be considered as a good stimulus for the secretion of Irisin.

  20. Early insulin sensitivity after restrictive bariatric surgery, inconsistency between HOMA-IR and steady-state plasma glucose levels.

    Science.gov (United States)

    van Dielen, Francois M H; Nijhuis, Jeroen; Rensen, Sander S M; Schaper, Nicolaas C; Wiebolt, Janneke; Koks, Afra; Prakken, Fred J; Buurman, Wim A; Greve, Jan Willem M

    2010-01-01

    The low-grade inflammatory condition present in morbid obesity is thought to play a causative role in the pathophysiology of insulin resistance (IR). Bariatric surgery fails to improve this inflammatory condition during the first months after surgery. Considering the close relation between inflammation and IR, we conducted a study in which insulin sensitivity was measured during the first months after bariatric surgery. Different methods to measure IR shortly after bariatric surgery have given inconsistent data. For example, the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) levels have been reported to decrease rapidly after bariatric surgery, although clamp techniques have shown sustained insulin resistance. In the present study, we evaluated the use of steady-state plasma glucose (SSPG) levels to assess insulin sensitivity 2 months after bariatric surgery. Insulin sensitivity was measured using HOMA-IR and SSPG levels in 11 subjects before surgery and at 26% excess weight loss (approximately 2 months after restrictive bariatric surgery). The SSPG levels after 26% excess weight loss did not differ from the SSPG levels before surgery (14.3 +/- 5.4 versus 14.4 +/- 2.7 mmol/L). In contrast, the HOMA-IR values had decreased significantly (3.59 +/- 1.99 versus 2.09 +/- 1.02). During the first months after restrictive bariatric surgery, we observed a discrepancy between the HOMA-IR and SSPG levels. In contrast to the HOMA-IR values, the SSPG levels had not improved, which could be explained by the ongoing inflammatory state after bariatric surgery. These results suggest that during the first months after restrictive bariatric surgery, HOMA-IR might not be an adequate marker of insulin sensitivity. Copyright 2010 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  1. Alternative translation initiation of Caveolin-2 desensitizes insulin signaling through dephosphorylation of insulin receptor by PTP1B and causes insulin resistance.

    Science.gov (United States)

    Kwon, Hayeong; Jang, Donghwan; Choi, Moonjeong; Lee, Jaewoong; Jeong, Kyuho; Pak, Yunbae

    2018-06-01

    Insulin resistance, defined as attenuated sensitivity responding to insulin, impairs insulin action. Direct causes and molecular mechanisms of insulin resistance have thus far remained elusive. Here we show that alternative translation initiation (ATI) of Caveolin-2 (Cav-2) regulates insulin sensitivity. Cav-2β isoform yielded by ATI desensitizes insulin receptor (IR) via dephosphorylation by protein-tyrosine phosphatase 1B (PTP1B), and subsequent endocytosis and lysosomal degradation of IR, causing insulin resistance. Blockage of Cav-2 ATI protects against insulin resistance by preventing Cav-2β-PTP1B-directed IR desensitization, thereby normalizing insulin sensitivity and glucose uptake. Our findings show that Cav-2β is a negative regulator of IR signaling, and identify a mechanism causing insulin resistance through control of insulin sensitivity via Cav-2 ATI. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. A hardware acceleration based on high-level synthesis approach for glucose-insulin analysis

    Science.gov (United States)

    Daud, Nur Atikah Mohd; Mahmud, Farhanahani; Jabbar, Muhamad Hairol

    2017-01-01

    In this paper, the research is focusing on Type 1 Diabetes Mellitus (T1DM). Since this disease requires a full attention on the blood glucose concentration with the help of insulin injection, it is important to have a tool that able to predict that level when consume a certain amount of carbohydrate during meal time. Therefore, to make it realizable, a Hovorka model which is aiming towards T1DM is chosen in this research. A high-level language is chosen that is C++ to construct the mathematical model of the Hovorka model. Later, this constructed code is converted into intellectual property (IP) which is also known as a hardware accelerator by using of high-level synthesis (HLS) approach which able to improve in terms of design and performance for glucose-insulin analysis tool later as will be explained further in this paper. This is the first step in this research before implementing the design into system-on-chip (SoC) to achieve a high-performance system for the glucose-insulin analysis tool.

  3. Comparison of insulin analogue B9AspB27Glu and soluble human insulin in insulin-treated diabetes.

    Science.gov (United States)

    Kang, S; Owens, D R; Vora, J P; Brange, J

    1990-02-10

    Postprandial plasma glucose excursions and plasma levels of free insulin after subcutaneous bolus injection of a rapidly absorbed monomeric insulin analogue (B9AspB27Glu) or soluble human insulin ('Actrapid HM' U100) were studied in six insulin-treated diabetic subjects. 10 U actrapid or an equimolar amount of the analogue were injected, in random order with an interval of 1 week, immediately before a 500 kcal test meal. Basal insulin levels were similar on the 2 study days (mean 74.1 [SE 5.1] pmol/l, actrapid; 79.7 [13.0] pmol/l, analogue). After injection of actrapid plasma free insulin levels rose slowly, reaching a plateau by 105 min at 222 (19) pmol/l. Injection of the analogue resulted in a rapid early peak at 30 min (798 [112] pmol/l), and levels were significantly higher than those after actrapid between 15 and 210 min. The more physiological plasma insulin levels achieved with the analogue were accompanied by a substantial reduction in postprandial plasma glucose excursions; the integrated area under the incremental plasma glucose curve was 45% lower after the analogue than after actrapid.

  4. Serum level of orexin-A, leptin, adiponectin and insulin in north Indian obese women.

    Science.gov (United States)

    Mishra, Sameeksha; Gupta, Vani; Mishra, Supriya; Sachan, Rekha; Asthana, Akash

    2017-12-01

    Obesity is regulated by different metabolic factors like leptin, adiponectin insulin and neuropeptide orexin-A. The aim of this study is to assess the role of these hormones and their interrelationship with obesity in north Indian women. A total of 168 obese women with Body Mass Index (BMI)>30kg/m 2 and 150 lean women (BMIWomen with obesity were further subdivided into two groups according to their BMI, 71 overweight women with the BMI 25-29.9kg/m 2 (mean±S.D: 27.87±0.71) and the 97 obese women with BMI>30kg/m 2 (34.68±1.90). Orexin -A, leptin and adiponectin were estimated using quantitative sandwich enzyme linked immunoassay and insulin was estimated by using an immuno-radiometric assay. Orexin -A and adiponectin level were significantly lower however, leptin and inulin level were significantly higher in obese women as compared with control group. Further, the one- way group analysis showed that the orexin -A and adiponectin level were significantly lower but leptin and insulin level was significantly higher in obese women as compared to overweight and control group respectively. Result showed that the level of adiponectin, leptin, orexin-A and insulin play an important role in the regulation of energy expenditure. In obesity, the activity of these peptides is disturbed. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  5. Urban-Rural Differences Explain the Association between Serum 25-Hydroxyvitamin D Level and Insulin Resistance in Korea

    Directory of Open Access Journals (Sweden)

    Bo Mi Song

    2014-12-01

    Full Text Available An increasing number of studies report associations between low serum 25-hydroxyvitamin D [25(OHD] level and insulin resistance; however, whether low vitamin D levels directly contribute to increased insulin resistance is unclear. We investigated the impact of residential area on the association between 25(OHD and insulin resistance in elderly Koreans. Using data from the Korean Urban Rural Elderly study, we conducted cross-sectional analyses in 1628 participants (505 men and 1123 women. Serum 25(OHD was analyzed as both continuous and categorized variables. Homeostasis model assessment for insulin resistance (HOMA-IR was calculated using fasting blood glucose and insulin levels. In men, 25(OHD level was inversely associated with HOMA-IR (standardized β = −0.133, p < 0.001 after adjustment for age, body mass index, waist circumference, smoking, alcohol intake, exercise, and study year. However, we noted significant urban-rural differences in 25(OHD level (43.4 versus 65.6 nmol/L; p < 0.001 and HOMA-IR (1.2 versus 0.8 mmol·pmol/L2; p < 0.001. When we additionally adjusted for residential area, the association between 25(OHD and HOMA-IR was attenuated (standardized β = −0.063, p = 0.115. In women, the association between 25(OHD and HOMA-IR was not significant before or after adjustment for residential area. Environmental or lifestyle differences in urban and rural areas may largely explain the inverse association between serum 25(OHD and insulin resistance.

  6. Studies of insulin resistance in congenital generalized lipodystrophy

    DEFF Research Database (Denmark)

    Søvik, O; Vestergaard, H; Trygstad, O

    1996-01-01

    suppressed lipid oxidation in the controls. It is concluded that patients with congenital generalized lipodystrophy may present severe insulin resistance with regard to hepatic glucose production as well as muscle glycogen synthesis and lipid oxidation. The results suggest a postreceptor defect in the action......, immunoreactive protein and mRNA levels. The patients had fasting hyperinsulinaemia, and the rate of total glucose disposal was severely impaired, primarily due to a decreased non-oxidative glucose metabolism. In the patient studied with muscle biopsy, the expected activation of glycogen synthase by insulin did...... not occur. In both patients there was severely increased hepatic glucose output in the basal state, suggesting a failure of insulin to suppress hepatic gluconeogenesis. During insulin infusion a substantially elevated rate of lipid oxidation remained in the patients, in contrast to the almost completely...

  7. Sex Differences in the Association between Level of Childhood Interleukin-6 and Insulin Resistance in Adolescence

    DEFF Research Database (Denmark)

    Bugge, Anna; El-Naaman, Bianca; G McMurray, Robert

    2012-01-01

    followed for 4 years. Anthropometrics and VO(2peak) were measured. Fasting blood samples were analyzed for IL-6, insulin, and glucose. Homeostasis model assessment (HOMA-IR) was used as a measure of insulin resistance. Results. For girls but not boys, levels of IL-6 at age 9 yrs correlated with HOMA-IR...... at age 13 yrs: r = 0.223, P = 0.008. Girls with IL-6 levels within the highest quartile at age 9 yrs had an odds ratio of 3.68 (CI = 1.58-8.57) being in the highest quartile of HOMA-IR four years later. Conclusion. In this cohort, IL-6 levels in childhood were related to insulin resistance in adolescence...

  8. Mendelian randomization studies do not support a causal role for reduced circulating adiponectin levels in insulin resistance and type 2 diabetes

    NARCIS (Netherlands)

    H. Yaghootkar (Hanieh); C. Lamina (Claudia); R.A. Scott (Robert); Z. Dastani (Zari); M.-F. Hivert (Marie-France); L.L. Warren (Liling); A. Stancáková (Alena); S.G. Buxbaum (Sarah); L.-P. Lyytikäinen (Leo-Pekka); P. Henneman (Peter); Y. Wu (Ying); C.Y.Y. Cheung (Chloe); J.S. Pankow (James); A.U. Jackson (Anne); S. Gustafsson (Stefan); J.H. Zhao (Jing Hua); C. Ballantyne (Christie); W. Xie (Weijia); R.N. Bergman (Richard); M. Boehnke (Michael); F. El Bouazzaoui (Fatiha); F.S. Collins (Francis); S.H. Dunn (Sandra); J. Dupuis (Josée); N.G. Forouhi (Nita); C.J. Gillson (Christopher); A.T. Hattersley (Andrew); J. Hong (Jaeyoung); M. Kähönen (Mika); J. Kuusisto (Johanna); L. Kedenko (Lyudmyla); F. Kronenberg (Florian); A. Doria (Andrea); T.L. Assimes (Themistocles); E. Ferrannini (Ele); T. Hansen (Torben); K. Hao (Ke); H. Häring (Hans); J.W. Knowles (Joshua); C.M. Lindgren (Cecilia); J.J. Nolan (John); J. Paananen (Jussi); O. Pedersen (Oluf); T. Quertermous (Thomas); U. Smith (Ulf); T. Lehtimäki (Terho); C.-T. Liu (Ching-Ti); R.J.F. Loos (Ruth); M.I. McCarthy (Mark); A.D. Morris (Andrew); R.S. Vasan (Ramachandran Srini); T.D. Spector (Timothy); T.M. Teslovich (Tanya); J. Tuomilehto (Jaakko); J.A.P. Willems van Dijk (Ko); J. Viikari (Jorma); N. Zhu (Na); C. Langenberg (Claudia); E. Ingelsson (Erik); R.K. Semple (Robert); A. Sinaiko (Alan); C.N.A. Palmer (Colin); M. Walker (Mark); K.S.L. Lam (Karen); B. Paulweber (Bernhard); K.L. Mohlke (Karen); C.M. van Duijn (Cornelia); O. Raitakari (Olli); A. Bidulescu (Aurelian); N.J. Wareham (Nick); M. Laakso (Markku); D. Waterworth (Dawn); D.A. Lawlor (Debbie); J.B. Meigs (James); J.B. Richards (Brent); T.M. Frayling (Timothy)

    2013-01-01

    textabstractAdiponectin is strongly inversely associated with insulin resistance and type 2 diabetes, but its causal role remains controversial. We used a Mendelian randomization approach to test the hypothesis that adiponectin causally influences insulin resistance and type 2 diabetes. We used

  9. Insulin-Sensitizer Effects of Fenugreek Seeds in Parallel with Changes in Plasma MCH Levels in Healthy Volunteers

    Directory of Open Access Journals (Sweden)

    Rita Kiss

    2018-03-01

    Full Text Available In developed, developing and low-income countries alike, type 2 diabetes mellitus (T2DM is one of the most common chronic diseases, the severity of which is substantially a consequence of multiple organ complications that occur due to long-term progression of the disease before diagnosis and treatment. Despite enormous investment into the characterization of the disease, its long-term management remains problematic, with those afflicted enduring significant degradation in quality-of-life. Current research efforts into the etiology and pathogenesis of T2DM, are focused on defining aberrations in cellular physiology that result in development of insulin resistance and strategies for increasing insulin sensitivity, along with downstream effects on T2DM pathogenesis. Ongoing use of plant-derived naturally occurring materials to delay the onset of the disease or alleviate symptoms is viewed by clinicians as particularly desirable due to well-established efficacy and minimal toxicity of such preparations, along with generally lower per-patient costs, in comparison to many modern pharmaceuticals. A particularly attractive candidate in this respect, is fenugreek, a plant that has been used as a flavouring in human diet through recorded history. The present study assessed the insulin-sensitizing effect of fenugreek seeds in a cohort of human volunteers, and tested a hypothesis that melanin-concentrating hormone (MCH acts as a critical determinant of this effect. A test of the hypothesis was undertaken using a hyperinsulinemic euglycemic glucose clamp approach to assess insulin sensitivity in response to oral administration of a fenugreek seed preparation to healthy subjects. Outcomes of these evaluations demonstrated significant improvement in glucose tolerance, especially in patients with impaired glucose responses. Outcome data further suggested that fenugreek seed intake-mediated improvement in insulin sensitivity correlated with reduction in MCH

  10. Decreased insulin secretion in pregnant rats fed a low protein diet.

    Science.gov (United States)

    Gao, Haijun; Ho, Eric; Balakrishnan, Meena; Yechoor, Vijay; Yallampalli, Chandra

    2017-10-01

    Low protein (LP) diet during pregnancy leads to reduced plasma insulin levels in rodents, but the underlying mechanisms remain unclear. Glucose is the primary insulin secretagogue, and enhanced glucose-stimulated insulin secretion (GSIS) in beta cells contributes to compensation for insulin resistance and maintenance of glucose homeostasis during pregnancy. In this study, we hypothesized that plasma insulin levels in pregnant rats fed LP diet are reduced due to disrupted GSIS of pancreatic islets. We first confirmed reduced plasma insulin levels, then investigated in vivo insulin secretion by glucose tolerance test and ex vivo GSIS of pancreatic islets in the presence of glucose at different doses, and KCl, glibenclamide, and L-arginine. Main findings include (1) plasma insulin levels were unaltered on day 10, but significantly reduced on days 14-22 of pregnancy in rats fed LP diet compared to those of control (CT) rats; (2) insulin sensitivity was unchanged, but glucose intolerance was more severe in pregnant rats fed LP diet; (3) GSIS in pancreatic islets was lower in LP rats compared to CT rats in the presence of glucose, KCl, and glibenclamide, and the response to L-arginine was abolished in LP rats; and (4) the total insulin content in pancreatic islets and expression of Ins2 were reduced in LP rats, but expression of Gcg was unaltered. These studies demonstrate that decreased GSIS in beta cells of LP rats contributes to reduced plasma insulin levels, which may lead to placental and fetal growth restriction and programs hypertension and other metabolic diseases in offspring. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Influence of Grand Multiparity on the Levels of Insulin, Glucose and HOMA-IR in Comparison with Nulliparity and Primiparity.

    Science.gov (United States)

    Eldin Ahmed Abdelsalam, Kamal; Alobeid M Elamin, Abdelsamee

    2017-01-01

    It is to compare the levels of fasting glucose and insulin as well as insulin resistance in grand multiparas with primiparity and nulliparity. Fasting blood samples were collected from 100 non-pregnant ladies as control group, 100 primiparity pregnant women and 100 grand multiparity pregnant women. Glucose (FBS) and insulin (FSI) concentrations were measured by Hitachi 912 full automated Chemistry Analyzer (Roche Diagnostics, Germany) as manufacturer procedure. Insulin resistance was calculated following the formula: FBG (mg dL-1)×FSI (μU mL-1)/405. This study found a significant reduction in glucose level in primiparity when compared to control group but it was increased significantly in multiparity comparing to primiparity and control. Insulin level showed significant high concentrations in pregnant women and increased significantly in grand multiparas comparing to primiparas and controls. As a result of that, HOMA-IR was increased significantly by increasing of parity. Also, there was a significant increase in fasting insulin and a decrease in insulin sensitivity with parity with association to age and obesity. Grand multiparity is associated with an increased risk of subsequent clinical insulin resistance (HOMA-IR).

  12. Relationship between Optimum Mini-doses of Glucagon and Insulin Levels when Treating Mild Hypoglycaemia in Patients with Type 1 Diabetes - A Simulation Study

    DEFF Research Database (Denmark)

    Ranjan, Ajenthen; Wendt, Sabrina Lyngbye; Schmidt, Signe

    2017-01-01

    -treated type 1 diabetes. In each simulation, one of ten different and individualized subcutaneous insulin boluses was administered to decrease plasma glucose (PG) from 7.0 to ≤3.9 mmol/l. Insulin levels were estimated as ratio of actual to baseline serum insulin concentration (se/ba-insulin), insulin on board...... (IOB) or percentage of IOB to total daily insulin dose (IOB/TDD). Insulin bolus sizes were chosen to provide pre-defined insulin levels when PG reached 3.9 mmol/l, where one of 17 subcutaneous glucagon boluses was administered. Optimum glucagon bolus to treat mild hypoglycaemia at varying insulin...... levels was the lowest dose that in most patients caused PG peak between 5.0 and 10.0 mmol/l and sustained PG ≥ 3.9 mmol/l for 2 hr after the bolus. PG response to glucagon declined with increasing insulin levels. The glucagon dose to optimally treat mild hypoglycaemia depended exponentially on insulin...

  13. Insulin resistance and increased muscle cytokine levels in patients with mitochondrial myopathy.

    Science.gov (United States)

    Rue, Nana; Vissing, John; Galbo, Henrik

    2014-10-01

    Mitochondrial dysfunction has been proposed to cause insulin resistance and that might stimulate cytokine production. The objective of the study was to elucidate the association between mitochondrial myopathy, insulin sensitivity, and cytokine levels in muscle. This was an experimental, controlled study in outpatients. Eight overnight-fasted patients (P) with various inherited mitochondrial myopathies and eight healthy subjects (C) matched for sex, age, weight, height, and physical activity participated in the study. The intervention included a 120-minute hyperinsulinemic, euglycemic clamp. Another morning, microdialysis of both vastus lateralis muscles for 4 hours, including one-legged, knee extension exercise for 30 minutes, was performed. Glucose infusion rate during 90-120 minutes of insulin infusion was measured. Cytokine concentrations in dialysate were also measured. Muscle strength, percentage fat mass, and creatine kinase in plasma did not differ between groups. The maximal oxygen uptake was 21 ± 3 (SE) (P) and 36 ± 3(C) mL/kg·min (2P fatty acids and glycerol at 120 minutes were higher in P vs C (2P myopathies, insulin sensitivity of muscle, adipose tissue, and pancreatic A cells is reduced, supporting that mitochondrial function influences insulin action. Furthermore, a local, low-grade inflammation of potential clinical importance exists in the muscle of these patients.

  14. Mendelian Randomisation Studies Do Not Support a Causal Role for Reduced Circulating Adiponectin Levels in Insulin Resistance and Type 2 Diabetes

    DEFF Research Database (Denmark)

    Yaghootkar, Hanieh; Lamina, Claudia; Scott, Robert A

    2013-01-01

    Adiponectin is strongly inversely associated with insulin resistance and type 2 diabetes but its causal role remains controversial. We used a Mendelian randomisation approach to test the hypothesis that adiponectin causally influences insulin resistance and type 2 diabetes. We used genetic varian...

  15. High-level expression of human insulin receptor cDNA in mouse NIH 3T3 cells

    International Nuclear Information System (INIS)

    Whittaker, J.; Okamoto, A.K.; Thys, R.; Bell, G.I.; Steiner, D.F.; Hofmann, C.A.

    1987-01-01

    In order to develop a simple, efficient system for the high-level expression of human insulin receptors in eukaryotic cells, a full-length human kidney insulin receptor cDNA was inserted into a bovine papilloma virus vector under the control of the mouse metallothionein promoter. After transfection of mouse NIH 3T3 cells with this construct, seven cell lines expressing insulin receptors were isolated; two cell lines had more than 10 6 receptors per cell. The cell line with the highest 125 I-insulin binding (NIH 3T3 HIR3.5) had 6 x 10 6 receptors with a K/sub d/ of 10 -9 M. This level was not dependent on exposure to metals but could be increased further to 2 x 10 7 receptors per cell by addition of sodium butyrate to the culture medium. The α and β subunits had apparent molecular weights of 147,000 and 105,000, respectively (compared to 135,000 and 95,000 in IM-9 human lymphocytes), values identical to those of the α and β subunits of the insulin receptors of nontransformed NIH 3T3 cells. This size difference was due to altered carbohydrate composition, as N-glycanase digestion reduced the apparent receptor subunit size of the transfected cells and IM-9 lymphocytes to identical values. The alteration in N-linked oligosaccharide composition could not be ascribed to differences in the kinetics of posttranslational processing of the insulin receptors, which was comparable to that of other cells studied. The basal rate of glycogen synthesis in the cells overexpressing insulin receptors was increased 4- to 5-fold compared with controls. Low levels of added insulin (0.1 nM) caused a 50% increase in the rate of glycogen synthesis

  16. Circulating Zinc-α2-glycoprotein levels and Insulin Resistance in Polycystic Ovary Syndrome

    Science.gov (United States)

    Lai, Yerui; Chen, Jinhua; Li, Ling; Yin, Jingxia; He, Junying; Yang, Mengliu; Jia, Yanjun; Liu, Dongfang; Liu, Hua; Liao, Yong; Yang, Gangyi

    2016-01-01

    The aim of study was to assess the relationship between zinc-α2-glycoprotein (ZAG) and androgen excess with insulin resistance in polycystic ovary syndrome (PCOS) women. 99 PCOS women and 100 healthy controls were recruited. Euglycemic-hyperinsulinemic clamp (EHC) was preformed to assess their insulin sensitivity. Circulating ZAG was determined with an ELISA kit. In healthy subjects, circulating ZAG levels exhibited a characteristic diurnal rhythm in humans, with a major nocturnal rise occurring between midnight and early morning. Circulating ZAG and M-value were much lower in PCOS women than in the controls. In all population, overweight/obese subjects had significantly lower circulating ZAG levels than lean individuals. Multiple linear regression analysis revealed that only M-value and the area under the curve for glucose were independently related factors to circulating ZAG in PCOS women. Multivariate logistic regression analysis showed that circulating ZAG was significantly associated with PCOS even after controlling for anthropometric variables, blood pressure, lipid profile and hormone levels. The PCOS women with high ZAG had fewer MetS, IGT and polycystic ovaries as compared with the low ZAG PCOS women. Taken together, circulating ZAG levels are reduced in women with PCOS and ZAG may be a cytokine associated with insulin resistance in PCOS women. PMID:27180914

  17. Association between Follicular Fluid Leptin and Serum Insulin Levels in Nonoverweight Women with Polycystic Ovary Syndrome

    Directory of Open Access Journals (Sweden)

    G. Garruti

    2014-01-01

    Full Text Available Aims. We evaluated the links between leptin and visfatin levels and fertilization rates in nonoverweight (NOW women with PCOS (NOW-PCOS from Apulia undergoing in vitro fertilization/embryo transfer (IVF. Materials and Methodology. We recruited 16 NOW women with PCOS (NOW-PCOS and 10 normally ovulating NOW women (control-NOW. All women underwent IVF. Androgens, 17-β-estradiol (17β-E2, and insulin levels were measured in plasma and/or serum and leptin and visfatin levels were assayed in both serum and follicular fluid (FF-leptin, FF-visfatin. Results. In NOW-PCOS, both serum and FF-leptin were significantly lower than in control-NOW. In NOW-PCOS, significant correlations were found between BMI and serum leptin and insulinemia and FF-leptin. By contrast, in control-NOW, FF-leptin levels were not correlated with insulinemia. Serum visfatin levels were not significantly different in NOW-PCOS and control-NOW, but FF-visfatin levels were 1.6-fold higher, although not significantly, in NOW-PCOS than in control-NOW. Conclusions. Both serum leptin levels and FF-leptin are BMI- and insulin-related in Southern Italian NOW-PCOS from Apulia. In line with other reports showing that FF-leptin levels are predictive of fertilization rates, lower than normal FF-leptin levels in NOW-PCOS may explain their lower fertilization rate and this may be related to the level of insulin and/or insulin resistance.

  18. How does brain insulin resistance develop in Alzheimer's disease?

    Science.gov (United States)

    De Felice, Fernanda G; Lourenco, Mychael V; Ferreira, Sergio T

    2014-02-01

    Compelling preclinical and clinical evidence supports a pathophysiological connection between Alzheimer's disease (AD) and diabetes. Altered metabolism, inflammation, and insulin resistance are key pathological features of both diseases. For many years, it was generally considered that the brain was insensitive to insulin, but it is now accepted that this hormone has central neuromodulatory functions, including roles in learning and memory, that are impaired in AD. However, until recently, the molecular mechanisms accounting for brain insulin resistance in AD have remained elusive. Here, we review recent evidence that sheds light on how brain insulin dysfunction is initiated at a molecular level and why abnormal insulin signaling culminates in synaptic failure and memory decline. We also discuss the cellular basis underlying the beneficial effects of stimulation of brain insulin signaling on cognition. Discoveries summarized here provide pathophysiological background for identification of novel molecular targets and for development of alternative therapeutic approaches in AD. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  19. Reduced Circulating Insulin Enhances Insulin Sensitivity in Old Mice and Extends Lifespan

    Directory of Open Access Journals (Sweden)

    Nicole M. Templeman

    2017-07-01

    Full Text Available The causal relationships between insulin levels, insulin resistance, and longevity are not fully elucidated. Genetic downregulation of insulin/insulin-like growth factor 1 (Igf1 signaling components can extend invertebrate and mammalian lifespan, but insulin resistance, a natural form of decreased insulin signaling, is associated with greater risk of age-related disease in mammals. We compared Ins2+/− mice to Ins2+/+ littermate controls, on a genetically stable Ins1 null background. Proteomic and transcriptomic analyses of livers from 25-week-old mice suggested potential for healthier aging and altered insulin sensitivity in Ins2+/− mice. Halving Ins2 lowered circulating insulin by 25%–34% in aged female mice, without altering Igf1 or circulating Igf1. Remarkably, decreased insulin led to lower fasting glucose and improved insulin sensitivity in aged mice. Moreover, lowered insulin caused significant lifespan extension, observed across two diverse diets. Our study indicates that elevated insulin contributes to age-dependent insulin resistance and that limiting basal insulin levels can extend lifespan.

  20. Reduced Circulating Insulin Enhances Insulin Sensitivity in Old Mice and Extends Lifespan.

    Science.gov (United States)

    Templeman, Nicole M; Flibotte, Stephane; Chik, Jenny H L; Sinha, Sunita; Lim, Gareth E; Foster, Leonard J; Nislow, Corey; Johnson, James D

    2017-07-11

    The causal relationships between insulin levels, insulin resistance, and longevity are not fully elucidated. Genetic downregulation of insulin/insulin-like growth factor 1 (Igf1) signaling components can extend invertebrate and mammalian lifespan, but insulin resistance, a natural form of decreased insulin signaling, is associated with greater risk of age-related disease in mammals. We compared Ins2 +/- mice to Ins2 +/+ littermate controls, on a genetically stable Ins1 null background. Proteomic and transcriptomic analyses of livers from 25-week-old mice suggested potential for healthier aging and altered insulin sensitivity in Ins2 +/- mice. Halving Ins2 lowered circulating insulin by 25%-34% in aged female mice, without altering Igf1 or circulating Igf1. Remarkably, decreased insulin led to lower fasting glucose and improved insulin sensitivity in aged mice. Moreover, lowered insulin caused significant lifespan extension, observed across two diverse diets. Our study indicates that elevated insulin contributes to age-dependent insulin resistance and that limiting basal insulin levels can extend lifespan. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Leucine supplementation protects from insulin resistance by regulating adiposity levels.

    Directory of Open Access Journals (Sweden)

    Elke Binder

    Full Text Available BACKGROUND: Leucine supplementation might have therapeutic potential in preventing diet-induced obesity and improving insulin sensitivity. However, the underlying mechanisms are at present unclear. Additionally, it is unclear whether leucine supplementation might be equally efficacious once obesity has developed. METHODOLOGY/PRINCIPAL FINDINGS: Male C57BL/6J mice were fed chow or a high-fat diet (HFD, supplemented or not with leucine for 17 weeks. Another group of HFD-fed mice (HFD-pairfat group was food restricted in order to reach an adiposity level comparable to that of HFD-Leu mice. Finally, a third group of mice was exposed to HFD for 12 weeks before being chronically supplemented with leucine. Leucine supplementation in HFD-fed mice decreased body weight and fat mass by increasing energy expenditure, fatty acid oxidation and locomotor activity in vivo. The decreased adiposity in HFD-Leu mice was associated with increased expression of uncoupling protein 3 (UCP-3 in the brown adipose tissue, better insulin sensitivity, increased intestinal gluconeogenesis and preservation of islets of Langerhans histomorphology and function. HFD-pairfat mice had a comparable improvement in insulin sensitivity, without changes in islets physiology or intestinal gluconeogenesis. Remarkably, both HFD-Leu and HFD-pairfat mice had decreased hepatic lipid content, which likely helped improve insulin sensitivity. In contrast, when leucine was supplemented to already obese animals, no changes in body weight, body composition or glucose metabolism were observed. CONCLUSIONS/SIGNIFICANCE: These findings suggest that leucine improves insulin sensitivity in HFD-fed mice by primarily decreasing adiposity, rather than directly acting on peripheral target organs. However, beneficial effects of leucine on intestinal gluconeogenesis and islets of Langerhans's physiology might help prevent type 2 diabetes development. Differently, metabolic benefit of leucine supplementation

  2. Dietary leucine--an environmental modifier of insulin resistance acting on multiple levels of metabolism

    DEFF Research Database (Denmark)

    Macotela, Yazmin; Emanuelli, Brice; Bång, Anneli M

    2011-01-01

    homeostasis and insulin signaling. After 8 weeks on HFD, mice developed obesity, fatty liver, inflammatory changes in adipose tissue and insulin resistance at the level of IRS-1 phosphorylation, as well as alterations in metabolomic profile of amino acid metabolites, TCA cycle intermediates, glucose...... and cholesterol metabolites, and fatty acids in liver, muscle, fat and serum. Doubling dietary leucine reversed many of the metabolite abnormalities and caused a marked improvement in glucose tolerance and insulin signaling without altering food intake or weight gain. Increased dietary leucine was also associated......Environmental factors, such as the macronutrient composition of the diet, can have a profound impact on risk of diabetes and metabolic syndrome. In the present study we demonstrate how a single, simple dietary factor--leucine--can modify insulin resistance by acting on multiple tissues...

  3. Rapid changes in plasma androgens during insulin withdrawal in male type 1 (insulin-dependent) diabetics

    DEFF Research Database (Denmark)

    Madsbad, S; Gluud, C; Bennett, Patrick

    1986-01-01

    Plasma concentrations of testosterone, androstenedione and dihydrotestosterone were measured in 15 Type 1 (insulin-dependent) diabetics with (n = 8) and without (n = 7) B-cell function during 12 h of insulin withdrawal and compared with those of 8 normal subjects. Before insulin withdrawal......, testosterone and dihydrotestosterone concentrations were lower in the diabetics after 4 h of insulin withdrawal and remained so throughout the study. The concentrations of androstenedione were not significantly different between diabetics and normal subjects except after 4 h of insulin withdrawal. Despite...

  4. Effects of Eight-Weeks of Aerobic Training on Resistin Levels and Insulin Resistance in Sedentary Middle-Aged Women

    Directory of Open Access Journals (Sweden)

    Bahram Abedi

    2017-11-01

    Full Text Available Introduction: Resistin is an adipocyte-specific hormone secreted from adipose tissue which plays a significant role in the energy homeostasis and regulation of energy metabolism. The purpose of this study was to examine the effects of eight weeks of aerobic training on the resistin levels and insulin resistance in sedentary middle-aged women. Methods: In this quasi-experimental research, 20 sedentary women were randomly selected and assigned to two groups: experimental group, n=10, aged 47.70±5.35; and control, n=10, age 41.30±3.02, respectively. The participants in the training group performed an exercise protocol three times per week with the goal of 55 to 65 per cent of maximum heart rate. Before and after the completion, the resistin, insulin, glucose and insulin resistance levels were measured after 12 h of overnight fasting. Data were analyzed before and after the intervention by t-test. The significant level was defined as P≤0.05. Results: Aerobic training in compared with the control group showed significant effect in decreasing resistin levels (P=0.012, BMI (P=0.01, insulin resistance (P=0.01, and increasing VO2 max (P=0.004. Conclusion: It appears that eight weeks of aerobic training significantly changes the level of resistin and the insulin resistance index in sedentary middle-aged women. Plasma resistin may be associated with insulin resistance in sedentary women. In general, according to the results, we may say that an eight-week aerobic training with a significant reduction in plasma resistin has a preventive effect as a new and effective training method on insulin resistance in middle-aged sedentary women.

  5. Insulin Biosynthetic Interaction Network Component, TMEM24, Facilitates Insulin Reserve Pool Release

    Directory of Open Access Journals (Sweden)

    Anita Pottekat

    2013-09-01

    Full Text Available Insulin homeostasis in pancreatic β cells is now recognized as a critical element in the progression of obesity and type II diabetes (T2D. Proteins that interact with insulin to direct its sequential synthesis, folding, trafficking, and packaging into reserve granules in order to manage release in response to elevated glucose remain largely unknown. Using a conformation-based approach combined with mass spectrometry, we have generated the insulin biosynthetic interaction network (insulin BIN, a proteomic roadmap in the β cell that describes the sequential interacting partners of insulin along the secretory axis. The insulin BIN revealed an abundant C2 domain-containing transmembrane protein 24 (TMEM24 that manages glucose-stimulated insulin secretion from a reserve pool of granules, a critical event impaired in patients with T2D. The identification of TMEM24 in the context of a comprehensive set of sequential insulin-binding partners provides a molecular description of the insulin secretory pathway in β cells.

  6. Insulin sensitivity and insulin secretion at birth in intrauterine growth retarded infants.

    Science.gov (United States)

    Setia, Sajita; Sridhar, M G; Bhat, Vishnu; Chaturvedula, Lata; Vinayagamoorti, R; John, Mathew

    2006-06-01

    To study insulin sensitivity, secretion and relation of insulin levels with birth weight and ponderal index in intrauterine growth retarded (IUGR) infants at birth. We studied 30 IUGR and 30 healthy newborns born at term by vaginal delivery in Jipmer, Pondicherry, India. Cord blood was collected at the time of delivery for measurement of plasma glucose and insulin. When compared with healthy newborns, IUGR newborns had lower plasma glucose levels (mean 2.3+/-0.98 versus 4.1+/-0.51 mmol/L, p<0.001); lower plasma insulin levels (mean 4.5+/-2.64 versus 11.03+/-1.68 microU/L, p<0.001); higher insulin sensitivity calculated using G/I ratio (mean 11.6+/-5.1 versus 6.7+/-0.31, p<0.001), HOMA IS (mean 5.5+/-6.0 versus 0.53+/-0.15, p<0.001), and QUICKI (mean 0.47+/-0.12 versus 0.34+/-0.02, p<0.001); and decreased pancreatic beta-cell function test measured as I/G (mean 0.10+/-0.037 versus 0.15+/-0.006, p<0.001). A positive correlation was identified between insulin levels and birth weight in both the healthy control group (r2 = 0.17, p = 0.024) and IUGR group (r2 = 0.13, p = 0.048). However correlation of insulin levels with ponderal index was much more confident in both healthy control (r2 = 0.90, p<0.001) and IUGR groups (r2 = 0.28, p = 0.003). Insulin status correlated both with birth weight and ponderal index more confidently in control group than in IUGR group. At birth, IUGR infants are hypoglycaemic, hypoinsulinaemic and display increased insulin sensitivity and decreased pancreatic beta-cell function. Insulin levels correlate with ponderal index much more confidently than with birth weight.

  7. Bariatric surgery in morbidly obese insulin resistant humans normalises insulin signalling but not insulin-stimulated glucose disposal.

    Directory of Open Access Journals (Sweden)

    Mimi Z Chen

    Full Text Available Weight-loss after bariatric surgery improves insulin sensitivity, but the underlying molecular mechanism is not clear. To ascertain the effect of bariatric surgery on insulin signalling, we examined glucose disposal and Akt activation in morbidly obese volunteers before and after Roux-en-Y gastric bypass surgery (RYGB, and compared this to lean volunteers.The hyperinsulinaemic euglycaemic clamp, at five infusion rates, was used to determine glucose disposal rates (GDR in eight morbidly obese (body mass index, BMI=47.3 ± 2.2 kg/m(2 patients, before and after RYGB, and in eight lean volunteers (BMI=20.7 ± 0.7 kg/m2. Biopsies of brachioradialis muscle, taken at fasting and insulin concentrations that induced half-maximal (GDR50 and maximal (GDR100 GDR in each subject, were used to examine the phosphorylation of Akt-Thr308, Akt-473, and pras40, in vivo biomarkers for Akt activity.Pre-operatively, insulin-stimulated GDR was lower in the obese compared to the lean individuals (P<0.001. Weight-loss of 29.9 ± 4 kg after surgery significantly improved GDR50 (P=0.004 but not GDR100 (P=0.3. These subjects still remained significantly more insulin resistant than the lean individuals (p<0.001. Weight loss increased insulin-stimulated skeletal muscle Akt-Thr308 and Akt-Ser473 phosphorylation, P=0.02 and P=0.03 respectively (MANCOVA, and Akt activity towards the substrate PRAS40 (P=0.003, MANCOVA, and in contrast to GDR, were fully normalised after the surgery (obese vs lean, P=0.6, P=0.35, P=0.46, respectively.Our data show that although Akt activity substantially improved after surgery, it did not lead to a full restoration of insulin-stimulated glucose disposal. This suggests that a major defect downstream of, or parallel to, Akt signalling remains after significant weight-loss.

  8. The influence of the polymorphism in apolipoprotein B codon 2488 on insulin and lipid levels in a Danish twin population

    DEFF Research Database (Denmark)

    Bentzen, J; Poulsen, P; Vaag, A

    2002-01-01

    on parameters associated with the insulin resistance syndrome in Danish twins. METHODS: The effect of the polymorphism on lipid, glucose and insulin measures was studied in 548 same sex twins aged 55-74 years. RESULTS: The codon 2488 polymorphism influenced fasting triglyceride levels, as well as insulin......, as measured at 120 min in an oral glucose tolerance test. Subjects with the genotype T2488T had 14% higher triglyceride levels (P = 0.02) and 31% higher insulin levels (P = 0.004) than subjects with genotype C2488C. In twins discordant for genotype, the T-allele was associated with higher levels......AIMS: The apolipoprotein B codon 2488 polymorphism has been associated with the metabolism of lipoproteins in subjects with Type 2 diabetes. However, no data are available on the influence of the polymorphism on insulin or glucose metabolism. This study examines the impact of the polymorphism...

  9. Levels of insulin, insulin-like growth factor-I and thyroid hormones in relation to the body condition score changes in periparturient dairy cows

    Directory of Open Access Journals (Sweden)

    Fratrić Natalija

    2013-01-01

    Full Text Available The objective of this study was to determine the levels of insulin, insulin like growth factor I (IGF-I and thyroid hormones in relation to the body condition score (BCS of periparturient dairy cows. The study was carried out on twenty Holstein-Friesian dairy cows with average milk production of 7000 L/305 days in the previous lactation, parity ranging from 2-4. All cows were BCS scored during the early dry period, 7±3 days before and after parturition. Based on the BCS at the early dry period, cows were divided in two groups: cows with high BCS (3.75- 4.25, HBCS, n=10, and cows with moderate BCS (2.75-3.75, MBCS, n=10. Blood samples were taken at the time of BCS evaluation. Concentrations of insulin, IGF-I, triiodothyroinine (T3 and thyroxine (T4 were determined by radioimmunoassay (RIA, INEP-Zemun, Serbia. Statistical differences between mean values were determined using Student t-test (p0.05. IGF-I level in HBCS cows at days 7±3 before calving was significantly higher (16.28±3.07:11.76±2.28, p<0.01, with a reverse relationship after calving (3.77±1.64:8.46±2.37, p<0.01. Insulin level was significantly lower at 7±3 days before calving in HBCS cows (16.26±4.60:20.18±4.96mIU/L, p<0.05. Thyroid hormones levels were significantly lower in HBCS group et all examined periods. [Projekat Ministarstva nauke Republike Srbije, br. III 46002 i br. 31003

  10. Interaction between exogenous insulin, endogenous insulin, and glucose in type 2 diabetes patients.

    Science.gov (United States)

    Janukonyté, Jurgita; Parkner, Tina; Bruun, Niels Henrik; Lauritzen, Torsten; Christiansen, Jens Sandahl; Laursen, Torben

    2015-05-01

    Little is known about the influence of exogenous insulin and actual glucose levels on the release of endogenous insulin in insulin-treated type 2 diabetes mellitus (T2DM) patients. This study investigated the interaction among serum endogenous insulin (s-EI), serum exogenous insulin aspart (s-IAsp), and blood glucose levels in an experimental short-term crossover design. Eight T2DM patients (63.52 years old; range, 49-69 years; mean body mass index, 28.8±3.8 kg/m(2)) were randomized to treatment with individual fixed doses of insulin aspart (0.5-1.5 IU/h) as a continuous subcutaneous insulin infusion (CSII) during a 10-h period on two occasions with different duration of hyperglycemia: (1) transient hyperglycemia for 2 h (visit TH) and (2) continuous hyperglycemia for 12 h (visit CH). During steady state the variances of plasma glucose (p-glucose), s-IAsp, and s-EI were equal within visit TH and within visit CH, but variances were significantly higher during visit CH compared with visit TH. The s-IAsp reached lower levels at visit CH compared with visit TH (test for slope=1, P=0.005). The s-EI depended on p-glucose in a nonlinear fashion during the first 100 min of both visits when s-IAsp was undetectable (adjusted R(2)=0.9). A complex but statistically significant interaction among s-IAsp, s-EI, p-glucose, and patients was observed during measurable s-IAsp levels (adjusted R(2)=0.70). Endogenous and exogenous insulin showed higher variation during continuous hyperglycemia. Significantly lower levels of exogenous insulin were observed following CSII during continuous hyperglycemia compared with transient hyperglycemia. Endogenous insulin levels could in a complex way be explained by an individual interaction among p-glucose and serum exogenous insulin, if present.

  11. Glucocorticoid Antagonism Reduces Insulin Resistance and Associated Lipid Abnormalities in High-Fructose-Fed Mice.

    Science.gov (United States)

    Priyadarshini, Emayavaramban; Anuradha, Carani Venkatraman

    2017-02-01

    High intake of dietary fructose causes perturbation in lipid metabolism and provokes lipid-induced insulin resistance. A rise in glucocorticoids (GCs) has recently been suggested to be involved in fructose-induced insulin resistance. The objective of the study was to investigate the effect of GC blockade on lipid abnormalities in insulin-resistant mice. Insulin resistance was induced in mice by administering a high-fructose diet (HFrD) for 60 days. Mifepristone (RU486), a GC antagonist, was administered to HFrD-fed mice for the last 18 days, and the intracellular and extracellular GC levels, the glucocorticoid receptor (GR) activation and the expression of GC-regulated genes involved in lipid metabolism were examined. HFrD elevated the intracellular GC content in both liver and adipose tissue and enhanced the GR nuclear translocation. The plasma GC level remained unchanged. The levels of free fatty acids and triglycerides in plasma were elevated, accompanied by increased plasma insulin and glucose levels and decreased hepatic glycogen content. Treatment with RU486 reduced plasma lipid levels, tissue GC levels and the expression of GC-targeted genes involved in lipid accumulation, and it improved insulin sensitivity. This study demonstrated that HFrD-induced lipid accumulation and insulin resistance are mediated by enhanced GC in liver and adipose tissue and that GC antagonism might reduce fructose-induced lipid abnormalities and insulin resistance. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  12. Insulin resistance, insulin response, and obesity as indicators of metabolic risk

    DEFF Research Database (Denmark)

    Ferrannini, Ele; Balkau, Beverley; Coppack, Simon W

    2007-01-01

    CONTEXT: Insulin resistance (IR) and obesity, especially abdominal obesity, are regarded as central pathophysiological features of a cluster of cardiovascular risk factors (CVRFs), but their relative roles remain undefined. Moreover, the differential impact of IR viz. insulin response has not been...... evaluated. OBJECTIVE: The objective of this study was to dissect out the impact of obesity, abdominal obesity, and IR/insulin response on CVRF. DESIGN: This was a cross-sectional study. SETTING: The study was conducted at 21 research centers in Europe. SUBJECTS: The study included a cohort of 1308......-cholesterol, and lower high-density lipoprotein-cholesterol, and insulin response to higher heart rate, blood pressure and fasting glucose, and the same dyslipidemic profile as IR (P

  13. Meal-induced platelet activation in diabetes mellitus type 1 or type 2 is related to postprandial insulin rather than glucose levels.

    Science.gov (United States)

    Spectre, Galia; Stålesen, Ragnhild; Östenson, Claes-Göran; Hjemdahl, Paul

    2016-05-01

    Postprandial platelet activation was related to postprandial insulin rather than glucose levels in a previous meal insulin study in type 2 diabetes mellitus (T2DM). We therefore compared postprandial platelet activation in type 1 (T1DM) patients without insulin secretion and T2DM patients with high postprandial insulin levels. Patients with T1DM (n=11) and T2DM (n=12) were studied before and 90min after a standardized meal without premeal insulin. Five T1DM patients volunteered for a restudy with their regular premeal insulin. Platelet activation was assessed by flow cytometry, with and without the thromboxane analogue U46619 or ADP, and by whole blood aggregometry (Multiplate®). Effects of insulin (100μU/mL) in vitro were also studied. Before the meal, glucose, insulin and platelet activation markers other than platelet-leukocyte aggregates (PLAs) were similar in T1DM and T2DM; PLAs were higher in T1DM. Postprandial glucose levels increased more markedly in T1DM (to 22.1±1.4 vs. 11.2±0.6mmol/L) while insulin levels increased only in T2DM (from 24.4±4.4 to 68.8±12.3μU/mL). Platelet P-selectin expression, fibrinogen binding and PLA formation stimulated by U46619 were markedly enhanced (approximately doubled) and whole blood aggregation stimulated by U46619 was increased (pinsulin in T1DM patients showed postprandial platelet activation when postprandial insulin levels increased. In vitro insulin mildly activated platelets in both groups. Postprandial platelet activation via the thromboxane pathway is related to postprandial hyperinsulinemia and not to postprandial hyperglycaemia in patients with diabetes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Lower adiponectin levels at first trimester of pregnancy are associated with increased insulin resistance and higher risk of developing gestational diabetes mellitus.

    Science.gov (United States)

    Lacroix, Marilyn; Battista, Marie-Claude; Doyon, Myriam; Ménard, Julie; Ardilouze, Jean-Luc; Perron, Patrice; Hivert, Marie-France

    2013-06-01

    To evaluate the associations between adiponectin levels and 1) the risk of developing gestational diabetes mellitus (GDM), and 2) insulin resistance/sensitivity, β-cell function, and compensation indices in a prospective cohort representative of the general population of pregnant women. We performed anthropometric measurements and collected blood samples at 1st (6-13 weeks) and 2nd (24-28 weeks) trimesters. Diagnosis of GDM was made at 2nd trimester based on a 75-g oral glucose tolerance test (International Association of the Diabetes and Pregnancy Study Groups criteria). Insulin was measured (ELISA; Luminex) to estimate homeostasis model assessment of insulin resistance (HOMA-IR), β-cell function (HOMA-B), insulin sensitivity (Matsuda index), insulin secretion (AUC(insulin/glucose)), and β-cell compensation (insulin secretion sensitivity index-2). Adiponectin was measured by radioimmunoassay. Among the 445 participants included in this study, 38 women developed GDM. Women who developed GDM had lower 1st-trimester adiponectin levels (9.67 ± 3.84 vs. 11.92 ± 4.59 µg/mL in women with normal glucose tolerance). Lower adiponectin levels were associated with higher risk of developing GDM (OR, 1.12 per 1 µg/mL decrease of adiponectin levels; P = 0.02, adjusted for BMI and HbA1c at 1st trimester). Adiponectin levels at 1st and 2nd trimesters were associated with HOMA-IR (both: r = -0.22, P insulin/glucose). Pregnant women with lower adiponectin levels at 1st trimester have higher levels of insulin resistance and are more likely to develop GDM independently of adiposity or glycemic measurements.

  15. White blood cell counts, insulin resistance, vitamin D levels and sarcopenia in Korean elderly men.

    Science.gov (United States)

    Kim, Sang-Hwan; Kwon, Hyun Seok; Hwang, Hee-Jin

    2017-05-01

    Sarcopenia is a major determinant of frailty, disability and mortality in the elderly. Whether low-grade inflammation, insulin resistance and vitamin D are independently associated with sarcopenia remains unclear. In our study, sarcopenia was defined as an appendicular skeletal muscle mass divided by height squared (ASM/Ht 2 ) that was sarcopenia in Korean elderly men aged more than 65 years was 11.2%. ASM/Ht 2 were positively associated with vitamin D levels, but negatively associated with white blood cell counts and HOMA-IR by multiple regression analysis. After adjustment for covariables, sarcopenia was associated with the highest quartile of WBC counts (OR = 2.93, 95% CI = 1.21-7.14) and the highest quartile of serum vitamin D levels (OR = 0.38, 95% CI = 0.15-0.95). In conclusion, the study findings suggest that higher WBC counts and lower vitamin D levels are independently associated with the presence of sarcopenia in community-dwelling elderly men. They also provide a basis for further studies of the complex immune-endocrine network in sarcopenia.

  16. Insulin Resistance Induced by Hyperinsulinemia Coincides with a Persistent Alteration at the Insulin Receptor Tyrosine Kinase Domain

    Science.gov (United States)

    Catalano, Karyn J.; Maddux, Betty A.; Szary, Jaroslaw; Youngren, Jack F.; Goldfine, Ira D.; Schaufele, Fred

    2014-01-01

    Insulin resistance, the diminished response of target tissues to insulin, is associated with the metabolic syndrome and a predisposition towards diabetes in a growing proportion of the worldwide population. Under insulin resistant states, the cellular response of the insulin signaling pathway is diminished and the body typically responds by increasing serum insulin concentrations to maintain insulin signaling. Some evidence indicates that the increased insulin concentration may itself further dampen insulin response. If so, insulin resistance would worsen as the level of circulating insulin increases during compensation, which could contribute to the transition of insulin resistance to more severe disease. Here, we investigated the consequences of excess insulin exposure to insulin receptor (IR) activity. Cells chronically exposed to insulin show a diminished the level of IR tyrosine and serine autophosphorylation below that observed after short-term insulin exposure. The diminished IR response did not originate with IR internalization since IR amounts at the cell membrane were similar after short- and long-term insulin incubation. Förster resonance energy transfer between fluorophores attached to the IR tyrosine kinase (TK) domain showed that a change in the TK domain occurred upon prolonged, but not short-term, insulin exposure. Even though the altered ‘insulin refractory’ IR TK FRET and IR autophosphorylation levels returned to baseline (non-stimulated) levels after wash-out of the original insulin stimulus, subsequent short-term exposure to insulin caused immediate re-establishment of the insulin-refractory levels. This suggests that some cell-based ‘memory’ of chronic hyperinsulinemic exposure acts directly at the IR. An improved understanding of that memory may help define interventions to reset the IR to full insulin responsiveness and impede the progression of insulin resistance to more severe disease states. PMID:25259572

  17. Insulin resistance induced by hyperinsulinemia coincides with a persistent alteration at the insulin receptor tyrosine kinase domain.

    Directory of Open Access Journals (Sweden)

    Karyn J Catalano

    Full Text Available Insulin resistance, the diminished response of target tissues to insulin, is associated with the metabolic syndrome and a predisposition towards diabetes in a growing proportion of the worldwide population. Under insulin resistant states, the cellular response of the insulin signaling pathway is diminished and the body typically responds by increasing serum insulin concentrations to maintain insulin signaling. Some evidence indicates that the increased insulin concentration may itself further dampen insulin response. If so, insulin resistance would worsen as the level of circulating insulin increases during compensation, which could contribute to the transition of insulin resistance to more severe disease. Here, we investigated the consequences of excess insulin exposure to insulin receptor (IR activity. Cells chronically exposed to insulin show a diminished the level of IR tyrosine and serine autophosphorylation below that observed after short-term insulin exposure. The diminished IR response did not originate with IR internalization since IR amounts at the cell membrane were similar after short- and long-term insulin incubation. Förster resonance energy transfer between fluorophores attached to the IR tyrosine kinase (TK domain showed that a change in the TK domain occurred upon prolonged, but not short-term, insulin exposure. Even though the altered 'insulin refractory' IR TK FRET and IR autophosphorylation levels returned to baseline (non-stimulated levels after wash-out of the original insulin stimulus, subsequent short-term exposure to insulin caused immediate re-establishment of the insulin-refractory levels. This suggests that some cell-based 'memory' of chronic hyperinsulinemic exposure acts directly at the IR. An improved understanding of that memory may help define interventions to reset the IR to full insulin responsiveness and impede the progression of insulin resistance to more severe disease states.

  18. Postreceptor defects causing insulin resistance in normoinsulinemic non-insulin-dependent diabetes mellitus

    International Nuclear Information System (INIS)

    Bolinder, J.; Ostman, J.; Arner, P.

    1982-01-01

    The mechanisms of the diminished hypoglycemic response to insulin in non-insulin-dependent diabetes mellitus (NIDDM) with normal levels of circulating plasma insulin were investigated. Specific binding of mono- 125 I (Tyr A14)-insulin to isolated adipocytes and effects of insulin (5--10,000 microunits/ml) on glucose oxidation and lipolysis were determined simultaneously in subcutaneous adipose tissue of seven healthy subjects of normal weight and seven untreated NIDDM patients with normal plasma insulin levels. The two groups were matched for age, sex, and body weight. Insulin binding, measured in terms of receptor number and affinity, was normal in NIDDM, the total number of receptors averaging 350,000 per cell. Neither sensitivity nor the maximum antilipolytic effect of insulin was altered in NIDDM patients as compared with control subjects; the insulin concentration producing half the maximum effect (ED50) was 10 microunits/ml. As regards the effect of insulin on glucose oxidation, for the control subjects ED50 was 30 microunits/ml, whereas in NIDDM patients, insulin exerted no stimulatory effect. The results obtained suggest that the effect of insulin on glucose utilization in normoinsulinemic NIDDM may be diminished in spite of normal insulin binding to receptors. The resistance may be due solely to postreceptor defects, and does not involve antilipolysis

  19. Urinary tract infection during pregnancy affects the level of leptin, ghrelin and insulin in maternal and placental blood.

    Science.gov (United States)

    Piatek, Jacek; Gibas-Dorna, Magdalena; Budzynski, Wlodzimierz; Krauss, Hanna; Marzec, Ewa; Olszewski, Jan; Zukiewicz-Sobczak, Wioletta

    2014-03-01

    We examined ghrelin, leptin and insulin in maternal blood during normal pregnancy and pregnancy complicated by urinary tract infection (UTI), as well as in cord blood at labor. A total of 36 delivering women with history of UTI during the third trimester of pregnancy were enrolled in the study; 12 healthy pregnant women served as a control. Infection markers (CRP and procalcitonin) were determined in maternal blood during the course of UTI and at labor. Ghrelin, leptin and insulin were determined during labor in venous maternal and in umbilical cord blood. We found negative correlation between infection markers in maternal blood during UTI, and level of tested hormones in cord blood, indicating potential risk of placental impairment due to energetic imbalance. We noted lower level of leptin in mothers with UTI and no change in leptin from umbilical blood comparing subjects with and without UTI. Low level of ghrelin was observed in maternal and cord blood when pregnancy was complicated by UTI. Insulin concentrations were high in mothers with UTI and low in their newborn's cord blood. Increased maternal insulin level could indicate peripheral insulin resistance caused by the infection. UTI during pregnancy affects the concentration of hormones responsible for regulating energetic homeostasis within the placenta.

  20. Association of Tumor Growth Factor-β and Interferon-γ Serum Levels With Insulin Resistance in Normal Pregnancy.

    Science.gov (United States)

    Sotoodeh Jahromi, Abdolreza; Sanie, Mohammad Sadegh; Yusefi, Alireza; Zabetian, Hassan; Zareian, Parvin; Hakimelahi, Hossein; Madani, Abdolhossien; Hojjat-Farsangi, Mohammad

    2015-09-28

    Pregnancy is related to change in glucose metabolism and insulin production. The aim of our study was to determine the association of serum IFN-γ and TGF- β levels with insulin resistance during normal pregnancy. This cross sectional study was carried out on 97 healthy pregnant (in different trimesters) and 28 healthy non-pregnant women. Serum TGF-β and IFN- γ level were measured by ELISA method. Pregnant women had high level TGF-β and low level IFN-γ as compared non-pregnant women. Maternal serum TGF-β concentration significantly increased in third trimester as compared first and second trimester of pregnancy. Maternal serum IFN-γ concentration significantly decreased in third trimester as compared first and second trimester of pregnancy. Pregnant women exhibited higher score of HOMA IR as compared non-pregnant women. There were association between gestational age with body mass index (r=0.28, P=0.005), TGF-β (r=0.45, PInsulin resistance and TGF-β (r=0.17, p=0.05). Our findings suggest that changes in maternal cytokine level in healthy pregnant women were anti-inflammatory. Furthermore, Tumor Growth Factor-β appears has a role in induction insulin resistance in healthy pregnant women. However, further studies needed to evaluate role of different cytokines on insulin resistance in normal pregnancy.

  1. Sodium retention and insulin treatment in insulin-dependent diabetes mellitus

    DEFF Research Database (Denmark)

    Nørgaard, K; Feldt-Rasmussen, B

    1994-01-01

    subcutaneously, contributes to the increased ENa. Three studies were performed. Study 1 was a cross-sectional study comprising 28 type 1 diabetic men (aged 18-35 years) with short-duration diabetes (diabetic complications, and 22 control subjects. Study 2 was a prospective study of 17...... subcutaneous insulin infusion for improvement of glycaemic control or to remain on conventional insulin treatment. In study 1, ENa was higher in short-duration type 1 diabetic men than in controls (3003 +/- 325 vs 2849 +/- 207 mEq/1.73 m2, P ...The hypothesis that total body exchangeable sodium (ENa) is elevated in type 1 (insulin-dependent) diabetic patients with short-duration diabetes and no signs of microangiopathy was tested. Also tested was whether peripheral hyperinsulinaemia, in terms of the amounts of insulin injected...

  2. [Insulin resistance in the pathogenesis of polycystic ovarian disease (PCOD)].

    Science.gov (United States)

    Jakowicki, J

    1994-10-01

    In polycystic ovarian disease there is a strong association between hyperinsulinemia and hyperandrogenism but not with obesity alone. The magnitude of peripheral insulin resistance is similar to that seen in non-insulin-dependent diabetes mellitus. Mild hyperinsulinemia in PCOD patients is not impair the carbohydrate metabolism. The elimination of the cause of hyperandrogenism by bilateral oophorectomy, long-acting Gn-RH agonist or antiandrogen cyproterone acetate did not improve the associated insulin resistance. In opposition to insulin resistance in the tissues responsible for metabolism of carbohydrate, the ovary remains sensitive to the effects of pancreatic hormone. Presumably this mechanism involved the interaction with IGF-I receptors to stimulate thecal and stromal androgen production. Insulin may sensitize the stroma to the stimulatory effect of LH. In the mechanism of follicular arrest take part increased level of binding proteins for IGF-I, mainly IGFBP 2, -4 and 5 inhibit FSH and IGF-I action.

  3. Effect of cigarette smoking on insulin resistance risk.

    Science.gov (United States)

    Haj Mouhamed, D; Ezzaher, A; Neffati, F; Douki, W; Gaha, L; Najjar, M F

    2016-02-01

    Smoking is one of the main risk factors for cardiovascular disease (CVD). The mechanism(s) of the effects of smoking on CVD are not clearly understood; however, a number of atherogenic characteristics, such as insulin resistance have been reported. We aim to investigate the effects of cigarette smoking on insulin resistance and to determine the correlation between this parameter with smoking status characteristics. This study was conducted on 138 non-smokers and 162 smokers aged respectively 35.6±16.0 and 38.5±21.9 years. All subjects are not diabetic. Fasting glucose was determined by enzymatic methods and insulin by chemiluminescence method. Insulin resistance (IR) was estimated using the Homeostasis Model of Assessment equation: HOMA-IR=[fasting insulin (mU/L)×fasting glucose (mmol/L)]/22.5. IR was defined as the upper quartile of HOMA-IR. Values above 2.5 were taken as abnormal and reflect insulin resistance. Compared to non-smokers, smokers had significantly higher levels of fasting glucose, fasting insulin and HOMA-IR index. These associations remained significant after adjustment for confounding factors (age, gender, BMI and alcohol consumption). A statistically significant association was noted between the smoking status parameters, including both the number of cigarettes smoked/day and the duration of smoking, and fasting insulin levels as well for HOMA-IR index. Among smokers, we noted a positive correlation between HOMA-IR index and both plasma thiocyanates and urinary cotinine. Our results show that smokers have a high risk to developing an insulin resistance and hyperinsulinemia, compared with a matched group of non-smokers, and may help to explain the high risk of cardiovascular diseases in smokers. Copyright © 2015. Published by Elsevier SAS.

  4. Subcutaneous insulin infusion: change in basal infusion rate has no immediate effect on insulin absorption rate

    International Nuclear Information System (INIS)

    Hildebrandt, P.; Birch, K.; Jensen, B.M.; Kuehl, C.

    1986-01-01

    Eight insulin-dependent diabetic patients were simultaneously given subcutaneous infusions (1.12 IU/h each) of 125 I-labeled Actrapid insulin in each side of the abdominal wall. After 24 h of infusion, the size of the infused insulin depots was measured by external counting for 5 h. The basal infusion rate was then doubled in one side and halved in the other for the next 4 h. Finally, 1.12 IU/h of insulin was given in both sides of the abdominal wall for an additional 3 h. The changes in the size of the depots were measured, and the absorption rates for each hour were calculated. During the first 5 h of infusion, the depot size was almost constant (approximately 5 IU) with an absorption rate that equaled the infusion rate. Doubling the infusion rate led to a significant increase in depot size, but the absorption rate remained unchanged for the first 3 h, and only thereafter was a significant increase seen. When the infusion rate was reduced to the initial 1.12 IU/h, the absorption rate remained elevated during the next 3 h. Correspondingly, when the infusion rate was decreased, the depot size also decreased, but the absorption rate remained unchanged for the first 3 h. The results show that a change in the basal insulin infusion rate does not lead to any immediate change in the insulin absorption rate. This should be considered when planning an insulin-infusion program that includes alteration(s) in the basal-rate setting

  5. Mechanisms for greater insulin-stimulated glucose uptake in normal and insulin-resistant skeletal muscle after acute exercise

    Science.gov (United States)

    2015-01-01

    Enhanced skeletal muscle and whole body insulin sensitivity can persist for up to 24–48 h after one exercise session. This review focuses on potential mechanisms for greater postexercise and insulin-stimulated glucose uptake (ISGU) by muscle in individuals with normal or reduced insulin sensitivity. A model is proposed for the processes underlying this improvement; i.e., triggers initiate events that activate subsequent memory elements, which store information that is relayed to mediators, which translate memory into action by controlling an end effector that directly executes increased insulin-stimulated glucose transport. Several candidates are potential triggers or memory elements, but none have been conclusively verified. Regarding potential mediators in both normal and insulin-resistant individuals, elevated postexercise ISGU with a physiological insulin dose coincides with greater Akt substrate of 160 kDa (AS160) phosphorylation without improved proximal insulin signaling at steps from insulin receptor binding to Akt activity. Causality remains to be established between greater AS160 phosphorylation and improved ISGU. The end effector for normal individuals is increased GLUT4 translocation, but this remains untested for insulin-resistant individuals postexercise. Following exercise, insulin-resistant individuals can attain ISGU values similar to nonexercising healthy controls, but after a comparable exercise protocol performed by both groups, ISGU for the insulin-resistant group has been consistently reported to be below postexercise values for the healthy group. Further research is required to fully understand the mechanisms underlying the improved postexercise ISGU in individuals with normal or subnormal insulin sensitivity and to explain the disparity between these groups after similar exercise. PMID:26487009

  6. Effect of Arctium Lappa Root Extract on Glucose Levels and Insulin Resistance in Rats with High Sucrose Diet

    Directory of Open Access Journals (Sweden)

    A Ahangarpour

    2013-06-01

    Full Text Available Introduction: Diabetes Mellitus is a growing health problem in all over the world. Arctium Lappa has been used therapeutically in Europe, North America and Asia. Antioxidants and antidiabetic compounds have been found in the root of Arctium Lappa. This study intends to investigate the effects of Arctium Lappa root aqueous extract on glucose, insulin levels and Fasting Insulin Resistance Index in female rats with high sucrose diet. Methods: 40 female Wistar rats weighting 150-250(g were applied. After having a diet induced by sucrose 50% in drinking water for 5 weeks, the animals were randomly divided into two groups of control, sucrose induced, and three groups of sucrose induced along with Arctium Lappa root aqueous extract (50,100,200 mg/Kg (8 rats in each group. Treatment by extracts was used during 2 weeks (i.p. and 24 hours after the last treatment, heart blood samples were gathered. After Blood samples were centrifuged, fasting plasma glucose (12 h was determined by kit and fasting insulin concentration was assayed by Enzyme-linked immunosorbent assay (Elisa methods. Result: Glucose levels, insulin and FIRI in sucrose group significantly increased in comparison with control group. Glucose levels in aqueous extract groups; 50 mg/kg (116.14±16.64mg/dl and 200 mg/kg (90.66±22.58 mg/dl in comparison with sucrose group (140.5±18.73 mg/dl significantly decreased. Insulin level and FIRI in all of aqueous extract groups were significantly decreased (P<0.001 in comparison with sucrose group. Conclusions: Arctium Lappa root aqueous extracts in animal model has revealed significant decrease in blood glucose and insulin levels.

  7. Skin Tags and Acanthosis Nigricans in Patients with Hepatitis C Infection in Relation to Insulin Resistance and Insulin Like Growth Factor-1 Levels

    Science.gov (United States)

    El Safoury, Omar Soliman; Shaker, Olfat G; Fawzy, May Mohsen

    2012-01-01

    Background: Skin tags (ST) are papillomas commonly found in the neck, axillae of middle-aged and elderly people Aim: Insulin and insulin-like growth factor (IGF-1) levels are affected by hepatitis C virus (HCV) infection and both of them may be implicated in the etiopathogenesis of ST and acanthosis nigricans (AN) through their proliferative and differentiating properties. So, the aim of this work was to evaluate the impact of HCV infection on ST and AN through the estimation of insulin resistance and IGF-1. Materials and Methods: Participants were arranged into four groups: (ST +ve / HCV +ve) 23 subjects, (ST+ / HCV -ve) 19 subjects, (HCV -ve / ST-ve) 20 subjects and (ST-ve /HCV +ve) 22 subjects. Age, ST size, color, number, AN, fasting glucose, fasting insulin, insulin resistance, IGF-1, HCV-antibodies (Ab) were recorded. Results: The mean number of ST in Group 1 was half the number of ST in Group 2 (11.0±9.3 / 22.3±14.0) (P=0.005). The difference in insulin resistance between the same groups was non-significant (13.1±10.6 / 9.0±5.5) (P=0.441) while the difference in IGF-1 was statistically significant (218.6±46.2 /285.4±32.8) (P=0.002). The multivariate logistic regression for the variables revealed that insulin resistance is the only factor affecting the occurrence of ST (OR=1.096, P=0.023). Multivariate regression analysis for the variables showed that HCV was borderline but not a significant factor affecting the number of ST (Beta=-0.409, P=0.053). The number of patients with AN was doubled in Group 2 in comparison to Group 1 but this was non significant 3(13%) / 6(32%) (P=0.2800). Conclusion: HCV is associated with a significant decrease in the ST number and in the serum level of IGF-1 together with an obvious decrease in the occurrence of AN. Our results may point to the entrant effect of insulin resistance and IGF-1 in ST and AN development. The current study suggests the evaluation of IGF-1-lowering agents in the control of ST and AN especially in

  8. Ethnic differences in the ability of triglyceride levels to identify insulin resistance.

    Science.gov (United States)

    Sumner, Anne E; Cowie, Catherine C

    2008-02-01

    The Metabolic Syndrome is used to predict the onset of coronary artery disease and Type 2 diabetes. As the predictive value of the Metabolic Syndrome has been challenged, alternative syndromes have been developed. All of these syndromes were developed in populations that were predominantly non-Hispanic white (NHW). They include the Enlarged Waist Elevated Triglyceride Syndrome, the Overweight-Lipid Syndrome and the Hypertriglyceridemic Waist Syndrome. The first applies to postmenopausal women, the second to overweight individuals (BMI> or =25 kg/m(2)), and the third to men. Each syndrome uses hypertriglyceridemia as a criterion. However, the definition of hypertriglyceridemia varies by syndrome i.e. TG> or =128 mg/dL for the Enlarged Waist Elevated Triglyceride Syndrome, TG> or =130 mg/dL for the Overweight-Lipid Syndrome, > or =150 mg/dL for the Metabolic Syndrome, and TG> or =176 mg/dL for the Hypertriglyceridemic Waist Syndrome. Insulin resistance and hypertriglyceridemia are highly correlated. But as insulin resistant non-Hispanic blacks (NHB) often have triglyceride (TG) levels below the thresholds set by these syndromes, the ability of either TG or these syndromes to identify high risk NHB is unknown. Using the National Health and Nutrition Examination Survey (NHANES) 1999-2002, our goals were to determine by ethnicity: (1) the prevalence of each of these syndromes; (2) the ability of fasting TG concentrations to identify insulin resistance at cut-off levels established by these syndromes, specifically 130, 150 and 176 mg/dL. Participants were 2804 adults from NHANES 1999-2002. The cohort was divided into tertiles of homeostasis model assessment. Insulin resistance was defined as the upper tertile (> or =2.73). The prevalence of each syndrome was lower in NHB than NHW or Mexican Americans (MA) (all Pidentify individuals at high risk for conditions such as cardiovascular disease and Type 2 diabetes, ethnic differences in TG levels should be considered.

  9. Relationship among Periodontal Disease, Insulin Resistance, Salivary Cortisol, and Stress Levels during Pregnancy.

    Science.gov (United States)

    Seraphim, Ana Paula Castilho Garcia; Chiba, Fernando Yamamoto; Pereira, Renato Felipe; Mattera, Maria Sara de Lima Coutinho; Moimaz, Suzely Adas Saliba; Sumida, Doris Hissako

    2016-01-01

    Pregnancy is a period involving important metabolic changes that enable the maintenance of the mother's health and development of the fetus. This study aimed to assess the relationship among periodontal disease, insulin resistance, salivary cortisol concentration and level of perceived stress in pregnant women. This was a cross-sectional study. The sample comprised 96 pregnant women between the fifth and seventh month of pregnancy registered at the Basic Health Units of the Unified Health System (SUS). The periodontal condition was assessed after obtainment free and informed consent from the participants. Participants were divided into three groups: control subjects with a healthy periodontal condition (CN; n=46), patients with gingivitis (GI; n=26), and patients with periodontitis (PI; n=24). Saliva and blood samples were collected for evaluation of salivary cortisol concentration, glycemia, insulinemia and Homeostasis Model Assessment-Insulin Resistance index. A validated survey for the assessment of perceived stress levels was also performed. PI group showed significantly higher (pperiodontal disease during pregnancy. This study emphasizes the importance of preventing periodontitis in order to avoid insulin resistance and stress during pregnancy since these can cause systemic complications for the mother and the fetus.

  10. Polymorphisms in FFAR4 (GPR120 Gene Modulate Insulin Levels and Sensitivity after Fish Oil Supplementation

    Directory of Open Access Journals (Sweden)

    Bastien Vallée Marcotte

    2017-11-01

    Full Text Available The objective was to test whether FFAR4 single nucleotide polymorphisms (SNPs are associated with glycemic control-related traits in humans following fish oil supplementation. A total of 210 participants were given 3 g/day of omega-3 (n-3 fatty acids (FA (1.9–2.2 g of eicosapentaenoic acid (EPA and 1.1 g of docosahexaenoic acid (DHA during six weeks. Biochemical parameters were taken before and after the supplementation. Using the HapMap database and the tagger procedure in Haploview, 12 tagging SNPs in FFAR4 were selected and then genotyped using TaqMan technology. Transcript expression levels were measured for 30 participants in peripheral mononuclear blood cells. DNA methylation levels were measured for 35 participants in leukocytes. In silico analyses were also performed. Four gene–diet interactions on fasting insulin levels and homeostatic model assessment of insulin resistance (HOMA-IR index values were found. rs17108973 explained a significant proportion of the variance of insulin levels (3.0% and HOMA-IR (2.03% index values. Splice site prediction was different depending on the allele for rs11187527. rs17108973 and rs17484310 had different affinity for transcription factors depending on the allele. n-3 FAs effectively improve insulin-related traits for major allele homozygotes of four FFAR4 SNPs as opposed to carriers of the minor alleles.

  11. The effect of a very low calorie diet on insulin sensitivity, beta cell function, insulin clearance, incretin hormone secretion, androgen levels and body composition in obese young women

    DEFF Research Database (Denmark)

    Svendsen, Pernille F; Jensen, Frank K; Holst, Jens Juul

    2012-01-01

    Evaluation of the effect of an 8-week very low calorie diet (VLCD, 500-600 kcal daily) on weight, body fat distribution, glucose, insulin and lipid metabolism, androgen levels and incretin secretion in obese women.......Evaluation of the effect of an 8-week very low calorie diet (VLCD, 500-600 kcal daily) on weight, body fat distribution, glucose, insulin and lipid metabolism, androgen levels and incretin secretion in obese women....

  12. Body composition using deuterated water, index of insulin resistance and cortisol levels in Costa Rican school in the metropolitan area

    International Nuclear Information System (INIS)

    Valverde Vindas, Allan Ignacio

    2014-01-01

    Body composition in the Costa Rican child population is evaluated and analyzed to determine the relationship with the index of insulin resistance and serum cortisol levels. 113 children in the metropolitan area were studied using deuterium isotope techniques as reference method for overweight and obesity. Morning cortisol levels were determined by immunoassay techniques (ELISA). The insulin resistance index of 113 Costa Rican boys and girls is obtained by the homeostatic method and the relationship between body composition with index of insulin resistance or levels of cortisol [es

  13. E4orf1 induction in adipose tissue promotes insulin-independent signaling in the adipocyte.

    Science.gov (United States)

    Kusminski, Christine M; Gallardo-Montejano, Violeta I; Wang, Zhao V; Hegde, Vijay; Bickel, Perry E; Dhurandhar, Nikhil V; Scherer, Philipp E

    2015-10-01

    Type 2 diabetes remains a worldwide epidemic with major pathophysiological changes as a result of chronic insulin resistance. Insulin regulates numerous biochemical pathways related to carbohydrate and lipid metabolism. We have generated a novel mouse model that allows us to constitutively activate, in an inducible fashion, the distal branch of the insulin signaling transduction pathway specifically in adipocytes. Using the adenoviral 36 E4orf1 protein, we chronically stimulate locally the Ras-ERK-MAPK signaling pathway. At the whole body level, this leads to reduced body-weight gain under a high fat diet challenge. Despite overlapping glucose tolerance curves, there is a reduced requirement for insulin action under these conditions. The mice further exhibit reduced circulating adiponectin levels that ultimately lead to impaired lipid clearance, and inflamed and fibrotic white adipose tissues. Nevertheless, they are protected from diet-induced hepatic steatosis. As we observe constitutively elevated p-Akt levels in the adipocytes, even under conditions of low insulin levels, this pinpoints enhanced Ras-ERK-MAPK signaling in transgenic adipocytes as a potential alternative route to bypass proximal insulin signaling events. We conclude that E4orf1 expression in the adipocyte leads to enhanced baseline activation of the distal insulin signaling node, yet impaired insulin receptor stimulation in the presence of insulin, with important implications for the regulation of adiponectin secretion. The resulting systemic phenotype is complex, yet highlights the powerful nature of manipulating selective branches of the insulin signaling network within the adipocyte.

  14. Insulin, Aging, and the Brain: Mechanisms and Implications

    OpenAIRE

    Akintola, Abimbola A.; van Heemst, Diana

    2015-01-01

    There is now an impressive body of literature implicating insulin and insulin signaling in successful aging and longevity. New information from in vivo and in vitro studies concerning insulin and insulin receptors has extended our understanding of the physiological role of insulin in the brain. However, the relevance of these to aging and longevity remains to be elucidated. Here, we review advances in our understanding of the physiological role of insulin in the brain, how insulin gets into t...

  15. Correlation analysis between bone density measured by quantitative CT and blood sugar level of aged patients with non-insulin-dependent diabetes mellitus

    International Nuclear Information System (INIS)

    Wang Guizhi; Liang Ping; Qiao Junhua; Liu Chunyan

    2008-01-01

    Objective: To approach the correlation between the bone density measured by quantitative CT and the blood sugar level of the aged patients with non-insulin-dependent diabetes mellitus, and observe the effects of the blood sugar level on the bone density. Methods: The lumbar bone densities and the blood sugar levels of 160 aged patients with non-insulin-dependent diabetes mellitus (hyperglycemia group 80 cases, euglycemia group 80 cases ) and the healthy aged people (80 cases) were detected by quantitative CT and serum biochemical detection; the correlation between the blood sugar level and the bone density and the osteoporosis occurrence status of aged people in various groups were analyzed. Results: The bone density in the non-insulin-dependent diabetes and hyperglycemia group was lower than those in normal (control) group and non-insulin-dependent diabetes and euglycemia group (P<0.05); the morbility of osteoporosis in the non-insulin-dependent diabetes and hyperglycemia group was higher than those in normal (control) group and non-insulin-dependent diabetes and euglycemia group (P<0.05); negative correlation was found between the bone density and the blood sugar level (aged male group: r=-0.7382, P=0.0013; aged female group: r=-0.8343, P=0.0007). Conclusion: The blood sugar level affects the bone density of the aged patients with non-insulin-dependent diabetes mellitus; the higher the blood sugar level, the lower the bone density. The non-insulin-dependent diabetes aged patients with hyperglycemia have the liability of osteoporosis. (authors)

  16. Insulin Resistance and Mitochondrial Dysfunction.

    Science.gov (United States)

    Gonzalez-Franquesa, Alba; Patti, Mary-Elizabeth

    2017-01-01

    Insulin resistance precedes and predicts the onset of type 2 diabetes (T2D) in susceptible humans, underscoring its important role in the complex pathogenesis of this disease. Insulin resistance contributes to multiple tissue defects characteristic of T2D, including reduced insulin-stimulated glucose uptake in insulin-sensitive tissues, increased hepatic glucose production, increased lipolysis in adipose tissue, and altered insulin secretion. Studies of individuals with insulin resistance, both with established T2D and high-risk individuals, have consistently demonstrated a diverse array of defects in mitochondrial function (i.e., bioenergetics, biogenesis and dynamics). However, it remains uncertain whether mitochondrial dysfunction is primary (critical initiating defect) or secondary to the subtle derangements in glucose metabolism, insulin resistance, and defective insulin secretion present early in the course of disease development. In this chapter, we will present the evidence linking mitochondrial dysfunction and insulin resistance, and review the potential for mitochondrial targets as a therapeutic approach for T2D.

  17. Plasma Ascorbic Acid in Insulin and Non-insulin Dependent Diabetes

    African Journals Online (AJOL)

    Blood glucose, plasma ascorbic acid and haemoglobin levels were estimated in insulin dependent diabetics, non-insulin dependent diabetics and controls matched for number, sex and age. Significantly higher levels of these parameters were found in control group than in the other two groups. Statistically differences were ...

  18. Comparative Study of Serum Leptin and Insulin Resistance Levels Between Korean Postmenopausal Vegetarian and Non-vegetarian Women.

    Science.gov (United States)

    Kim, Mi-Hyun; Bae, Yun-Jung

    2015-07-01

    The present study was conducted to compare serum leptin and insulin resistance levels between Korean postmenopausal long-term semi-vegetarians and non-vegetarians. Subjects of this study belonged to either a group of postmenopausal vegetarian women (n = 54), who maintained a semi-vegetarian diet for over 20 years or a group of non-vegetarian controls. Anthropometric characteristics, serum leptin, serum glucose, serum insulin, insulin resistance (HOMA-IR; Homeostasis Model Assessment of Insulin Resistance), and nutrient intake were compared between the two groups. The vegetarians showed significantly lower body weight (p vegetarians. The HOMA-IR of the vegetarians was significantly lower than that of the non-vegetarians (p vegetarian diet might be related to lower insulin resistance independent of the % of body fat in postmenopausal women.

  19. Effects of different levels of coconut fiber on blood glucose, serum insulin and minerals in rats.

    Science.gov (United States)

    Sindurani, J A; Rajamohan, T

    2000-01-01

    The effect of neutral detergent fiber (NDF) from coconut kernel (Cocos nucifera L) in rats fed 5%, 15% and 30% level on the concentration of blood glucose, serum insulin and excretion of minerals was studied. Increase in the intake of fiber resulted in significant decrease in the level of blood glucose and serum insulin. Faecal excretion of Cu, Cr, Mn, Mg, Zn and Ca was found to increase in rats fed different levels of coconut fiber when compared to fiber free group. The result of the present investigation suggest that inclusion of coconut fiber in the diet results in significant hypoglycemic action.

  20. Metformin and insulin receptors

    International Nuclear Information System (INIS)

    Vigneri, R.; Gullo, D.; Pezzino, V.

    1984-01-01

    The authors evaluated the effect of metformin (N,N-dimethylbiguanide), a biguanide known to be less toxic than phenformin, on insulin binding to its receptors, both in vitro and in vivo. Specific 125 I-insulin binding to cultured IM-9 human lymphocytes and MCF-7 human breast cancer cells was determined after preincubation with metformin. Specific 125 I-insulin binding to circulating monocytes was also evaluated in six controls, eight obese subjects, and six obese type II diabetic patients before and after a short-term treatment with metformin. Plasma insulin levels and blood glucose were also measured on both occasions. Metformin significantly increased insulin binding in vitro to both IM-9 lymphocytes and MCF-7 cells; the maximum increment was 47.1% and 38.0%, respectively. Metformin treatment significantly increased insulin binding in vivo to monocytes of obese subjects and diabetic patients. Scatchard analysis indicated that the increased binding was mainly due to an increase in receptor capacity. Insulin binding to monocytes of normal controls was unchanged after metformin as were insulin levels in all groups; blood glucose was significantly reduced after metformin only in diabetic patients. These data indicate that metformin increases insulin binding to its receptors in vitro and in vivo. The effect in vivo is observed in obese subjects and in obese type II diabetic patients, paralleling the clinical effectiveness of this antidiabetic agent, and is not due to receptor regulation by circulating insulin, since no variation in insulin levels was recorded

  1. Insulin Detemir Is Transported From Blood to Cerebrospinal Fluid and Has Prolonged Central Anorectic Action Relative to NPH Insulin

    Science.gov (United States)

    Begg, Denovan P.; May, Aaron A.; Mul, Joram D.; Liu, Min; D’Alessio, David A.; Seeley, Randy J.

    2015-01-01

    Insulin detemir (DET) reduces glycemia comparably to other long-acting insulin formulations but causes less weight gain. Insulin signaling in the brain is catabolic, reducing food intake. We hypothesized that DET reduces weight gain, relative to other insulins, owing to increased transport into the central nervous system and/or increased catabolic action within the brain. Transport of DET and NPH insulin into the cerebrospinal fluid (CSF) was compared over several hours and after the administration of different doses peripherally in rats. DET and NPH had comparable saturable, receptor-mediated transport into the CSF. CSF insulin remained elevated significantly longer after intraperitoneal DET than after NPH. When administered acutely into the 3rd cerebral ventricle, both DET and NPH insulin reduced food intake and body weight at 24 h, and both food intake and body weight remained lower after DET than after NPH after 48 h. In direct comparison with another long-acting insulin, insulin glargine (GLAR), DET led to more prolonged increases in CSF insulin despite a shorter plasma half-life in both rats and mice. Additionally, peripheral DET administration reduced weight gain and increased CSF insulin compared with saline or GLAR in mice. Overall, these data support the hypothesis that DET has distinct effects on energy balance through enhanced and prolonged centrally mediated reduction of food intake. PMID:25667307

  2. Mechanical stress regulates insulin sensitivity through integrin-dependent control of insulin receptor localization.

    Science.gov (United States)

    Kim, Jung; Bilder, David; Neufeld, Thomas P

    2018-01-15

    Insulin resistance, the failure to activate insulin signaling in the presence of ligand, leads to metabolic diseases, including type 2 diabetes. Physical activity and mechanical stress have been shown to protect against insulin resistance, but the molecular mechanisms remain unclear. Here, we address this relationship in the Drosophila larval fat body, an insulin-sensitive organ analogous to vertebrate adipose tissue and livers. We found that insulin signaling in Drosophila fat body cells is abolished in the absence of physical activity and mechanical stress even when excess insulin is present. Physical movement is required for insulin sensitivity in both intact larvae and fat bodies cultured ex vivo. Interestingly, the insulin receptor and other downstream components are recruited to the plasma membrane in response to mechanical stress, and this membrane localization is rapidly lost upon disruption of larval or tissue movement. Sensing of mechanical stimuli is mediated in part by integrins, whose activation is necessary and sufficient for mechanical stress-dependent insulin signaling. Insulin resistance develops naturally during the transition from the active larval stage to the immotile pupal stage, suggesting that regulation of insulin sensitivity by mechanical stress may help coordinate developmental programming with metabolism. © 2018 Kim et al.; Published by Cold Spring Harbor Laboratory Press.

  3. Intermittent hypoxia increases insulin resistance in genetically obese mice.

    Science.gov (United States)

    Polotsky, Vsevolod Y; Li, Jianguo; Punjabi, Naresh M; Rubin, Arnon E; Smith, Philip L; Schwartz, Alan R; O'Donnell, Christopher P

    2003-10-01

    Obstructive sleep apnoea, a syndrome that leads to recurrent intermittent hypoxia, is associated with insulin resistance in obese individuals, but the mechanisms underlying this association remain unknown. We utilized a mouse model to examine the effects of intermittent hypoxia on insulin resistance in lean C57BL/6J mice and leptin-deficient obese (C57BL/6J-Lepob) mice. In lean mice, exposure to intermittent hypoxia for 5 days (short term) resulted in a decrease in fasting blood glucose levels (from 173 +/- 11 mg dl-1 on day 0 to 138 +/- 10 mg dl-1 on day 5, P obese mice, short-term intermittent hypoxia led to a decrease in blood glucose levels accompanied by a 607 +/- 136 % (P intermittent hypoxia was completely abolished by prior leptin infusion. Obese mice exposed to intermittent hypoxia for 12 weeks (long term) developed a time-dependent increase in fasting serum insulin levels (from 3.6 +/- 1.1 ng ml-1 at baseline to 9.8 +/- 1.8 ng ml-1 at week 12, P intermittent hypoxia is dependent on the disruption of leptin pathways.

  4. Mediterranean diet and insulin sensitivity, lipid profile and blood pressure levels, in overweight and obese people; The Attica study

    Directory of Open Access Journals (Sweden)

    Zampelas Antonis

    2007-09-01

    Full Text Available Abstract Background We aimed to investigate if overweight and obese adults "close" to Mediterranean diet present better insulin, lipids profile and better pressure levels, compared to individuals close to a more Westernized diet. Methods The ATTICA study is a population-based cohort that has randomly enrolled 3042 adult men and women, stratified by age – gender, from the greater area of Athens, during 2001–2002. Of them, in this work were have studied 1762 participants with excess body weight, meaning overweight (BMI: 25–29.9 kg/m2 and obese (BMI>30 kg/m2. 1064 were men and 698 women (20–89 years old. Adherence to Mediterranean diet was assessed through a diet-score that was based on a validated food-frequency questionnaire. Blood pressure was measured and also fasting glucose, insulin and blood lipids. Insulin sensitivity was also assessed by the homeostasis model assessment (HOMA approach (glucose × insulin/22.5. Results Individuals with excess bodyweight in the highest tertile of diet score, were more insulin sensitive than those in the lowest tertile (11.4% lower HOMA, p = 0.06, had 13% lower levels of total cholesterol (p = 0.001 and 3 mmHg decrease of systolic blood pressure levels (p Conclusion Adherence to Mediterranean diet is modeslty associated with a better insulin sensitivity, lower levels of total cholesterol and lower levels of systolic blood pressure in overweight and obese subjects. This may suggest that compared to general population, the beneficial effect of this diet in cardiovascular system of excess body weight people is limited.

  5. Insulin secretion and insulin action in non-insulin-dependent diabetes mellitus: which defect is primary?

    Science.gov (United States)

    Reaven, G M

    1984-01-01

    Defects in both insulin secretion and insulin action exist in patients with non-insulin-dependent diabetes mellitus (NIDDM). The loss of the acute plasma insulin response to intravenous glucose is seen in patients with relatively mild degrees of fasting hyperglycemia, but patients with severe fasting hyperglycemia also demonstrate absolute hypoinsulinemia in response to an oral glucose challenge. In contrast, day-long circulating insulin levels are within normal limits even in severely hyperglycemic patients with NIDDM. The relationship between NIDDM and insulin action in NIDDM is less complex, and is a characteristic feature of the syndrome. This metabolic defect is independent of obesity, and the severity of the resistance to insulin-stimulated glucose uptake increases with magnitude of hyperglycemia. Control of hyperglycemia with exogenous insulin ameliorates the degree of insulin resistance, and reduction of insulin resistance with weight loss in obese patients with NIDDM leads to an enhanced insulin response. Since neither therapeutic intervention is capable of restoring all metabolic abnormalities to normal, these observations do not tell us which of these two defects is primarily responsible for the development of NIDDM. Similarly, the observation that most patients with impaired glucose tolerance are hyperinsulinemic and insulin resistant does not prove that insulin resistance is the primary defect in NIDDM. In conclusion, reduction in both insulin secretion and action is seen in patients with NIDDM, and the relationship between these two metabolic abnormalities is very complex.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Increased plasma levels of FABP4 and PTEN is associated with more severe insulin resistance in women with gestational diabetes mellitus.

    Science.gov (United States)

    Li, Yuan-yuan; Xiao, Rui; Li, Cai-ping; Huangfu, Jian; Mao, Jiang-feng

    2015-02-08

    The aim of this study was to investigate the relationship between plasma fatty acid binding protein 4 (FABP4), phosphatase and tensin homolog (PTEN), and insulin resistance in patients with gestational diabetes mellitus (GDM). Plasma FABP4 and PTEN were determined by ELISA in GDM patients (GDM group, n=30) and in euglycemic pregnant women (control group, n=30). The clinical features, body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR), and lipid profiles were compared between the 2 groups. The influence of risk factors on insulin resistance, including BMI, lipid profiles, FABP4, and PTEN, were further investigated by multiple-factor stepwise regression analysis. Higher levels of BMI, ΔBMI, triglyceride (TG), fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG), fasting insulin, HOMA-IR, FABP4, PTEN, and lower level of high-density lipoprotein cholesterol (HDL-C) were found in the GDM patients than in the controls (all Pinsulin resistance. GDM patients have more severe insulin resistance compared to euglycemic pregnant women. Higher levels of plasma FABP4 and PTEN are associated with increased insulin resistance and may participate in the pathogenesis of insulin resistance during gestation.

  7. Eradicating hepatitis C virus ameliorates insulin resistance without change in adipose depots.

    Science.gov (United States)

    Milner, K-L; Jenkins, A B; Trenell, M; Tid-Ang, J; Samocha-Bonet, D; Weltman, M; Xu, A; George, J; Chisholm, D J

    2014-05-01

    Chronic hepatitis C (CHC) is associated with lipid-related changes and insulin resistance; the latter predicts response to antiviral therapy, liver disease progression and the risk of diabetes. We sought to determine whether insulin sensitivity improves following CHC viral eradication after antiviral therapy and whether this is accompanied by changes in fat depots or adipokine levels. We compared 8 normoglycaemic men with CHC (genotype 1 or 3) before and at least 6 months post viral eradication and 15 hepatitis C antibody negative controls using an intravenous glucose tolerance test and two-step hyperinsulinaemic-euglycaemic clamp with [6,6-(2) H2 ] glucose to assess peripheral and hepatic insulin sensitivity. Magnetic resonance imaging and spectroscopy quantified abdominal fat compartments, liver and intramyocellular lipid. Peripheral insulin sensitivity improved (glucose infusion rate during high-dose insulin increased from 10.1 ± 1.6 to 12 ± 2.1 mg/kg/min/, P = 0.025), with no change in hepatic insulin response following successful viral eradication, without any accompanying change in muscle, liver or abdominal fat depots. There was corresponding improvement in incremental glycaemic response to intravenous glucose (pretreatment: 62.1 ± 8.3 vs post-treatment: 56.1 ± 8.5 mm, P = 0.008). Insulin sensitivity after viral clearance was comparable to matched controls without CHC. Post therapy, liver enzyme levels decreased but, interestingly, levels of glucagon, fatty acid-binding protein and lipocalin-2 remained elevated. Eradication of the hepatitis C virus improves insulin sensitivity without alteration in fat depots, adipokine or glucagon levels, consistent with a direct link of the virus with insulin resistance. © 2013 John Wiley & Sons Ltd.

  8. Herbal formula menoprogen alters insulin-like growth factor-1 and insulin-like growth factor binding protein-1 levels in the serum and ovaries of an aged female rat model of menopause.

    Science.gov (United States)

    Wei, Min; Zheng, Sheng Z; Lu, Ye; Liu, Daniel; Ma, Hong; Mahady, Gail B

    2015-10-01

    Menoprogen (MPG), a traditional Chinese medicine formula for menopause, improves menopausal symptoms; however, its mechanism remains unknown. Previous studies have shown that MPG is not directly estrogenic; thus, the goal of this study was to investigate the effects of MPG on insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-1 (IGFBP-1) levels in an aged female rat model of menopause. In a six-arm study, 14-month-old female Sprague-Dawley rats (n = 8 per arm) were randomly divided into the following groups: untreated aged, 17β-estradiol-treated aged (estradiol [E2]), and three arms with increasing doses of MPG (162, 324, or 648 mg/kg/d). The sixth arm contained 4-month-old female Sprague-Dawley rats as a normal comparison group. Four weeks after MPG or E2 administration, animals were killed after blood draws, and ovarian tissues were excised. Levels of E2 and progesterone (P4) were determined by radioimmunoassay. Serum and ovarian tissue levels of IGF-1, IGFBP-1, and IGF-1 receptor were determined by enzyme-linked immunosorbent assay. Compared with the normal group, aged rats had significantly reduced serum levels of E2, P4, and IGF-1, and increased serum and ovarian tissue levels of IGFBP-1. MPG restored serum IGF-1 and IGFBP-1 levels and down-regulated ovarian levels of IGFBP-1, which were closely related to increases in E2 and P4 levels in aged rats. No significant differences in either IGF-1 or IGFBP-1 were observed between the three doses of MPG. MPG exerts a direct in vivo effect on aged female rats by positively regulating serum and ovarian IGF-1 and IGFBP-1 levels.

  9. Insulin resistance in obese children and adolescents: HOMA-IR cut-off levels in the prepubertal and pubertal periods.

    Science.gov (United States)

    Kurtoğlu, Selim; Hatipoğlu, Nihal; Mazıcıoğlu, Mümtaz; Kendirici, Mustafa; Keskin, Mehmet; Kondolot, Meda

    2010-01-01

    Childhood obesity is associated with an increased risk for insulin resistance. The underlying mechanism for the physiological increase in insulin levels in puberty is not clearly understood. The aim of the present study was to determine the cut-off values for homeostasis model assessment for insulin resistance (HOMA-IR) in obese children and adolescents according to gender and pubertal status. Two hundred and eight obese children and adolescents (141 girls, 127 boys) aged between 5 and 18 years were included in the study. The children were divided into prepubertal and pubertal groups. A standard oral glucose tolerance test (OGTT) was carried out in all children. A total insulin level exceeding 300 μU/mL in the blood samples, collected during the test period, was taken as the insulin resistance criterion. Cut-off values for HOMA-IR were calculated by receiver operating characteristic (ROC) analysis. In the prepubertal period, the rate of insulin resistance was found to be 37% in boys and 27.8% in girls,while in the pubertal period, this rate was 61.7% in boys and 66.7% in girls. HOMA-IR cut-off values for insulin resistance in the prepubertal period were calculated to be 2.67 (sensitivity 88.2%, specificity 65.5%) in boys and 2.22 (sensitivity 100%, specificity 42.3%) in girls, and in the pubertal period, they were 5.22 (sensitivity 56%, specificity 93.3%) in boys and 3.82 (sensitivity 77.1%, specificity 71.4%) in girls. Since gender, obesity and pubertal status are factors affecting insulin resistance, cut-off values which depend on gender and pubertal status, should be used in evaluation of insulin resistance.

  10. Ghrelin- and GH-induced insulin resistance

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

    2013-01-01

    Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects.......Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

  11. Effects of a fibre-enriched milk drink on insulin and glucose levels in healthy subjects

    Directory of Open Access Journals (Sweden)

    Pilvi Taru K

    2009-10-01

    Full Text Available Abstract Background The glycaemic response to foods is dependent on the quality and content of carbohydrates. Carbohydrates in the form of dietary fibre have favourable effects on insulin and glucose metabolism and may help to control energy intake. Dairy products have a relatively low carbohydrate content, and most of the carbohydrate is in the form of lactose which causes gastrointestinal symptoms in part of the population. In order to avoid these symptoms, dairy products can be replaced with lactose-free dairy products which are on the market in many parts of the world. However, the effects of lactose-free products on insulin and glucose metabolism have not been studied. Methods In the present study, we investigated the effects of 1 a lactose-free milk drink, 2 a novel fibre-enriched, fat- and lactose-free milk drink and 3 normal fat-free milk on serum glucose and insulin levels and satiety using a randomized block design. Following an overnight fast, 26 healthy volunteers ingested 200 ml of one of these drinks on three non-consecutive days. Insulin and glucose levels and subjective satiety ratings were measured before the ingestion of the milk product and 20, 40, 60, 120 and 180 minutes after ingestion. The responses were calculated as the area under the curve subtracted by the baseline value (AUC minus baseline. Results The insulin response was significantly lower for the fibre-enriched milk drink than it was for the other milk products (AUC, P = 0.007. There were no differences in the response for glucose or in the AUC for the subjective satiety ratings between the studied milk products. Conclusion The present results suggest that this novel milk drink could have positive effects on insulin response.

  12. Efficacy of nanogold-insulin as a hypoglycemic agent

    International Nuclear Information System (INIS)

    Ehsan, O.; Qadir, M.I.; Malik, A.A.; Abbasi, W.S.; Ahmad, B.

    2012-01-01

    Nano materials have gained tremendous importance in biology and medicine, because they can be used as carriers for delivering small molecules such as drugs, proteins and genes. We have reported the binding of insulin to gold nanoparticles and its application or efficiency in subcutaneous delivery for the therapeutic treatment of diabetes mellitus. The inert gas condensation (IGC) process was used in the synthesis of gold nanoparticles. A total of hundred rabbits were used in this study. Twenty rabbits were normal designated as Group A. The remaining eighty rabbits were divided into 4 groups. In Groups B, C and D diabetes was induced by giving streptozotocin and named Diabetic control, Diabetic insulin treated and Diabetic nG-I conjugate treated respectively. It was concluded from the study that there is a significant reduction of blood glucose levels when insulin is delivered using gold nanoparticles as carriers by the subcutaneous route in diabetic rabbits and this reduction in the blood glucose level was sustained for a significantly longer period. (author)

  13. Solid lipid nanoparticles for pulmonary delivery of insulin.

    Science.gov (United States)

    Liu, Jie; Gong, Tao; Fu, Hualin; Wang, Changguang; Wang, Xiuli; Chen, Qian; Zhang, Qin; He, Qin; Zhang, Zhirong

    2008-05-22

    Growing attention has been given to the potential of pulmonary route as an alternative for non-invasive systemic delivery of therapeutic agents. In this study, novel nebulizer-compatible solid lipid nanoparticles (SLNs) for pulmonary drug delivery of insulin were developed by reverse micelle-double emulsion method. The influences of the amount of sodium cholate (SC) and soybean phosphatidylcholine (SPC) on the deposition properties of the nanoparticles were investigated. Under optimal conditions, the entrapment delivery (ED), respirable fraction (RF) and nebulization efficiency (NE) of SLNs could reach 96.53, 82.11 and 63.28%, respectively, and Ins-SLNs remained stable during nebulization. Fasting plasma glucose level was reduced to 39.41% and insulin level was increased to approximately 170 microIU/ml 4h after pulmonary administration of 20 IU/kg Ins-SLNs. A pharmacological bioavailability of 24.33% and a relative bioavailability of 22.33% were obtained using subcutaneous injection as a reference. Incorporating fluorescent-labelled insulin into SLNs, we found that the SLNs were effectively and homogeneously distributed in the lung alveoli. These findings suggested that SLNs could be used as a potential carrier for pulmonary delivery of insulin by improving both in vitro and in vivo stability as well as prolonging hypoglycemic effect, which inevitably resulted in enhanced bioavailability.

  14. Fatty-acid binding protein 4 gene variants and childhood obesity: potential implications for insulin sensitivity and CRP levels

    Directory of Open Access Journals (Sweden)

    Bhattacharjee Rakesh

    2010-02-01

    Full Text Available Abstract Introduction Obesity increases the risk for insulin resistance and metabolic syndrome in both adults and children. FABP4 is a member of the intracellular lipid-binding protein family that is predominantly expressed in adipose tissue, and plays an important role in maintaining glucose and lipid homeostasis. The purpose of this study was to measure FABP4 plasma levels, assess FABP4 allelic variants, and explore potential associations with fasting glucose and insulin levels in young school-age children with and without obesity. Methods A total of 309 consecutive children ages 5-7 years were recruited. Children were divided based on BMI z score into Obese (OB; BMI z score >1.65 and non-obese (NOB. Fasting plasma glucose, lipids, insulin, hsCRP, and FABP4 levels were measured. HOMA was used as correlate of insulin sensitivity. Four SNPs of the human FABP4 gene (rs1051231, rs2303519, rs16909233 and rs1054135, corresponding to several critical regions of the encoding FABP4 gene sequence were genotyped. Results Compared to NOB, circulating FABP4 levels were increased in OB, as were LDL, hsCRP and HOMA. FABP4 levels correlated with BMI, and also contributed to the variance of HOMA and hsCRP, but not serum lipids. The frequency of rs1054135 allelic variant was increased in OB, and was associated with increased FABP4 levels, while the presence of rs16909233 variant allele, although similar in OB and NOB, was associated with increased HOMA values. Conclusions Childhood obesity is associated with higher FABP4 levels that may promote cardiometabolic risk. The presence of selective SNPs in the FABP4 gene may account for increased risk for insulin resistance or systemic inflammation in the context of obesity.

  15. Investigation on the correlationship between plasma homocysteine and blood glucose, insulin levels in patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Ma Zhongwei

    2005-01-01

    Objective: To explore the correlationship between plasma homocysteine and blood glucose, insulin levels in patients with type 2 diabetes mellitus. Methods: Plasma homocysteine (with ELISA), blood glucose (with hexokinase method) and insulin (with RIA) levels were measured in 66 patients with type 2 diabetes mellitus as well as in 35 controls. Results: Plasma homocysteine levels in the diabetic patients (n=66) were significantly higher than those in controls (P<0.01), especially in those patients complicated with nephropathy (n=32). The homocysteine levels were positively correlated with those of blood glucose and insulin (r=0.3515, r=0.3486, both P<0.01). Conclusion: Plasma homocysteine is an independent risk factor for vascular diseases. The levels of plasma cysteine are significantly increased in patients with type 2 diabetes mellitus, especially in those complicated with nephropathy. Therefore, monitoring of plasma homocysteine level changes is clinically useful. (authors)

  16. Plasma levels of lysine, tyrosine, and valine during pregnancy are independent risk factors of insulin resistance and gestational diabetes.

    Science.gov (United States)

    Park, Sunmin; Park, Jin Young; Lee, Ju Hong; Kim, Sung-Hoon

    2015-03-01

    This study compared plasma concentrations of amino acids in pregnant women with and without gestational diabetes mellitus (GDM) and identified the association between plasma amino acid levels and GDM, insulin resistance, and insulin secretion at 24-28 weeks of pregnancy. Circulating amino acid levels were evaluated using high-performance liquid chromatography at 24-28 weeks of pregnancy in 25 non-GDM and 64 GDM women after adjusting for covariates such as maternal age, body mass index (BMI) before pregnancy, BMI and gestational age at screening GDM, and daily caloric intake. Backward stepwise logistic regression analysis was used to identify the predictors of developing GDM, and homeostatic model assessments for insulin resistance (HOMA-IR) and β-cell function (HOMA-B). Circulating levels of amino acids except threonine and tyrosine were significantly higher in GDM women than non-GDM women. Along with the intakes of energy, protein, and fat from animal sources, the intakes of each amino acid were significantly higher in the GDM group without a direct correlation to plasma amino acid levels. The variation in GDM development was explained by maternal age, diastolic blood pressure, and plasma lysine levels (R(2)=0.691). Height, BMI before pregnancy, systolic blood pressure, and plasma tyrosine and valine levels accounted for the variation in HOMA-IR (R(2)=0.589). The 53.3% variation of HOMA-B was explained by maternal age, BMI at GDM screening, plasma insulin level at 1 h during the oral glucose tolerance test (OGTT), and plasma valine level. Circulating concentrations of lysine, tyrosine, and valine were independently and positively associated with GDM through modifying insulin resistance and secretion.

  17. Circulating ApoJ is closely associated with insulin resistance in human subjects.

    Science.gov (United States)

    Seo, Ji A; Kang, Min-Cheol; Ciaraldi, Theodore P; Kim, Sang Soo; Park, Kyong Soo; Choe, Charles; Hwang, Won Min; Lim, Dong Mee; Farr, Olivia; Mantzoros, Christos; Henry, Robert R; Kim, Young-Bum

    2018-01-01

    Insulin resistance is a major risk factor for type 2 diabetes. ApolipoproteinJ (ApoJ) has been implicated in altered pathophysiologic states including cardiovascular and Alzheimer's disease. However, the function of ApoJ in regulation of glucose homeostasis remains unclear. This study sought to determine whether serum ApoJ levels are associated with insulin resistance in human subjects and if they change after interventions that improve insulin sensitivity. Serum ApoJ levels and insulin resistance status were assessed in nondiabetic (ND) and type 2 diabetic (T2D) subjects. The impacts of rosiglitazone or metformin therapy on serum ApoJ levels and glucose disposal rate (GDR) during a hyperinsulinemic/euglycemic clamp were evaluated in a separate cohort of T2D subjects. Total ApoJ protein or that associated with the HDL and LDL fractions was measured by immunoblotting or ELISA. Fasting serum ApoJ levels were greatly elevated in T2D subjects (ND vs T2D; 100±8.3 vs. 150.6±8.5AU, Pinsulin, HOMA-IR, and BMI. ApoJ levels were significantly and independently associated with HOMA-IR, even after adjustment for age, sex, and BMI. Rosiglitazone treatment in T2D subjects resulted in a reduction in serum ApoJ levels (before vs. after treatment; 100±13.9 vs. 77±15.2AU, P=0.015), whereas metformin had no effect on ApoJ levels. The change in ApoJ levels during treatment was inversely associated with the change in GDR. Interestingly, ApoJ content in the LDL fraction was inversely associated with HOMA-IR. Serum ApoJ levels are closely correlated with the magnitude of insulin resistance regardless of obesity, and decrease along with improvement of insulin resistance in response only to rosiglitazone in type 2 diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Relationship of Neonatal Leptin and Insulin to Birth Weight and Gender Difference as well as Their Relationship to Maternal Levels

    International Nuclear Information System (INIS)

    Ashry, Kh.M.

    2005-01-01

    Normal intrauterine growth and development is dependent on many factors of which hormonal factors have been implicated. The aim of the present work was to study the relationship of neonatal leptin and insulin to birth weight and gender difference as well as their relationship to maternal levels. Serum leptin level was assessed by competitive enzyme immunoassay and insulin level by radioimmunoassay in the cord blood of sixty neonates and the venous blood of their mothers. The neonates were classified according to their birth weight into: 23 appropriate for gestational age (AGA) (12 females and 11 males); 20 large for gestational age (LGA) (11 females and 9 males) and 17 small for gestational age (SGA) (9 femals and 8 males). Our results revealed a highly significant increase in maternal serum levels of leptin and insulin (24.1±11.8 ng/ml and 22.3±5.8 μ U/ml, respectively) when compared to neonatal levels (10.0 ± 7.4ng/ml and 7.4±4.3 μ U/ml, p<0.001, respectively). Cord blood leptin and insulin levels showed statistically significant differences between all weight classes with the highest levels in LGA neonates

  19. Effect of physical activity level on biomarkers of inflammation and insulin resistance over 5 years in outpatients with coronary heart disease (from the Heart and Soul Study).

    Science.gov (United States)

    Jarvie, Jennifer L; Whooley, Mary A; Regan, Mathilda C; Sin, Nancy L; Cohen, Beth E

    2014-10-15

    Higher levels of physical activity are associated with lower rates of coronary heart disease (CHD). Previous studies have suggested that this is due partly to lower levels of inflammation and insulin resistance. The aim of this study was to determine whether physical activity level was associated with inflammation or insulin resistance during a 5-year period in outpatients with known CHD. A total of 656 participants from the Heart and Soul Study, a prospective cohort study of outpatients with documented CHD, were evaluated. Self-reported physical activity frequency was assessed at baseline and after 5 years of follow-up. Participants were classified as low versus high activity at each visit, yielding 4 physical activity groups: stable low activity, decreasing activity (high at baseline to low at year 5), increasing activity (low at baseline to high at year 5), and stable high activity. Year 5 markers of inflammation (C-reactive protein [CRP], interleukin-6, and fibrinogen) and insulin resistance (insulin, glucose, and glycated hemoglobin) were compared across the 4 activity groups. After 5 years of follow-up, higher activity was associated with lower mean levels of all biomarkers. In the fully adjusted regression models, CRP, interleukin-6, and glucose remained independently associated with physical activity frequency (log CRP, p for trend across activity groups = 0.03; log interleukin-6, p for trend = 0.01; log glucose, p for trend = 0.003). Subjects with stable high activity typically had the lowest levels of biomarkers. In conclusion, in this novel population of outpatients with known CHD followed for 5 years, higher physical activity frequency was independently associated with lower levels of CRP, interleukin-6, and glucose. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. [Associations of insulin resistance and pancreatic beta-cell function with plasma glucose level in type 2 diabetes].

    Science.gov (United States)

    Nian, Xiaoping; Sun, Gaisheng; Dou, Chunmei; Hou, Hongbo; Fan, Xiuping; Yu, Hongmei; Ma, Ling; He, Bingxian

    2002-06-10

    To investigate the influence of insulin resistance and pancreatic beta-cell function on plasma glucose level in type 2 diabetes so as to provide theoretical basis for reasonable selection of hypoglycemic agents. The plasma non-specific insulin (NSINS), true insulin (TI) and glucose in eight-one type 2 diabetics, 38 males and 43 females, with a mean age of 53 years, were examined 0, 30, 60 and 120 minutes after they had 75 grams of instant noodles. The patients were divided into two groups according to their fasting plasma glucose (FPG): group A (FPG = 8.89 mmol/L). The insulin resistance was evaluated by HOMA-IR, the beta-cell function was evaluated by HOMA-beta formula and the formula deltaI(30)/deltaG(30) = (deltaI(30)-deltaI(0))/(deltaG(30)-deltaG(0)). The insulin area under curve (INSAUC) was evaluated by the formula INSAUC=FINS/2+INS(30)+INS(60)+INS(120)/2. The mean FPG was 6.23 mmol/L in group A and 12.6 mmol/L in group B. PG2H was 11.7 mmol/L in group A and 19.2 mmol/L in group B. The TI levels in group B at 0, 30, 60, 120 min during standard meal test were significantly higher than those in group A: 6.15 +/- 1.06 vs 4.77 +/- 1.06, 9.76 +/- 1.1 vs 5.88 +/- 1.1,14.68 +/- 1.11 vs 6.87 +/- 1.1 and 17.13 +/- 1.12 vs 8.0 +/- 1.1 microU/dl (all P< 0.01). The NSINS showed the same trend. The insulin resistance in group B was 1.5 times that in group A. With the insulin resistance adjusted, the beta cell function in group A was 5 to 6 times that in group B. The INSAUC in group A was 1.66 times larger than that in group B, especially the INSAUC for true insulin (2 times larger). The contribution of insulin resistance and beta cell function to PG2H was half by half in group A and 1:8 in group B. beta cell function calculated by insulin (Homa-beta) explained 41% of the plasma glucose changes in group A and 54% of the plasma glucose changes in group B. The contribution of insulin deficiency to plasma glocose was 3.3.times that of insulin resistance in group A and was 9

  1. Persistence of insulin resistance in polycystic ovarian disease after inhibition of ovarian steroid secretion.

    Science.gov (United States)

    Geffner, M E; Kaplan, S A; Bersch, N; Golde, D W; Landaw, E M; Chang, R J

    1986-03-01

    Six nonobese women with polycystic ovarian disease (PCOD) showed significant hyperinsulinemia, compared with controls after oral glucose (P less than 0.05). As an indicator of insulin sensitivity, in vitro proliferation of erythrocyte progenitor cells of PCOD subjects exposed to physiologic concentrations of insulin was significantly blunted (P less than 0.001). Monocyte insulin receptor binding was not impaired in the PCOD subjects. Three of the PCOD patients were treated with a long-acting gonadotropin-releasing hormone agonist for 6 months, which resulted in marked suppression of ovarian androgen secretion but no demonstrable changes in in vivo or in vitro indicators of insulin resistance. Thus insulin resistance in PCOD subjects appears to be unrelated to ovarian hyperandrogenism (or acanthosis or obesity). Although certain tissues are insulin-resistant in PCOD patients, the ovary may remain sensitive and overproduce androgens in response to high circulating insulin levels.

  2. Obesity is the main determinant of insulin resistance more than the circulating pro-inflammatory cytokines levels in rheumatoid arthritis patients.

    Science.gov (United States)

    Castillo-Hernandez, Jesus; Maldonado-Cervantes, Martha Imelda; Reyes, Juan Pablo; Patiño-Marin, Nuria; Maldonado-Cervantes, Enrique; Solorzano-Rodriguez, Claudia; de la Cruz Mendoza, Esperanza; Alvarado-Sanchez, Brenda

    Systemic blockade of TNF-α in Rheumatoid arthritis with insulin resistance seems to produce more improvement in insulin sensitivity in normal weight patients with Rheumatoid arthritis than in obese patients with Rheumatoid arthritis, suggesting that systemic-inflammation and obesity are independent risk factors for insulin resistance in Rheumatoid arthritis patients. To evaluate the insulin resistance in: normal weight patients with Rheumatoid arthritis, overweight patients with Rheumatoid arthritis, obese Rheumatoid arthritis patients, and matched control subjects with normal weight and obesity; and its association with major cytokines involved in the pathogenesis of the disease. Assessments included: body mass index, insulin resistance by Homeostasis Model Assessment, ELISA method, and enzymatic colorimetric assay. Outstanding results from these studies include: (1) In Rheumatoid arthritis patients, insulin resistance was well correlated with body mass index, but not with levels of serum cytokines. In fact, levels of cytokines were similar in all Rheumatoid arthritis patients, regardless of being obese, overweight or normal weight (2) Insulin resistance was significantly higher in Rheumatoid arthritis with normal weight than in normal weight (3) No significant difference was observed between insulin resistances of Rheumatoid arthritis with obesity and obesity (4) As expected, levels of circulating cytokines were significantly higher in Rheumatoid arthritis patients than in obesity. Obesity appears to be a dominant condition above inflammation to produce IR in RA patients. The dissociation of the inflammation and obesity components to produce IR suggests the need of an independent therapeutic strategy in obese patients with RA. Copyright © 2017. Published by Elsevier Editora Ltda.

  3. Tau hyperphosphorylation induces oligomeric insulin accumulation and insulin resistance in neurons.

    Science.gov (United States)

    Rodriguez-Rodriguez, Patricia; Sandebring-Matton, Anna; Merino-Serrais, Paula; Parrado-Fernandez, Cristina; Rabano, Alberto; Winblad, Bengt; Ávila, Jesús; Ferrer, Isidre; Cedazo-Minguez, Angel

    2017-12-01

    Insulin signalling deficiencies and insulin resistance have been directly linked to the progression of neurodegenerative disorders like Alzheimer's disease. However, to date little is known about the underlying molecular mechanisms or insulin state and distribution in the brain under pathological conditions. Here, we report that insulin is accumulated and retained as oligomers in hyperphosphorylated tau-bearing neurons in Alzheimer's disease and in several of the most prevalent human tauopathies. The intraneuronal accumulation of insulin is directly dependent on tau hyperphosphorylation, and follows the tauopathy progression. Furthermore, cells accumulating insulin show signs of insulin resistance and decreased insulin receptor levels. These results suggest that insulin retention in hyperphosphorylated tau-bearing neurons is a causative factor for the insulin resistance observed in tauopathies, and describe a novel neuropathological concept with important therapeutic implications. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Effects of glucose, insulin, and insulin resistance on cerebral 18F-FDG distribution in cognitively normal older subjects

    Science.gov (United States)

    Onishi, Airin; Fujiwara, Yoshinori; Ishiwata, Kiichi; Ishii, Kenji

    2017-01-01

    Background Increasing plasma glucose levels and insulin resistance can alter the distribution pattern of fluorine-18-labeled fluorodeoxyglucose (18F-FDG) in the brain and relatively reduce 18F-FDG uptake in Alzheimer's disease (AD)-related hypometabolic regions, leading to the appearance of an AD-like pattern. However, its relationship with plasma insulin levels is unclear. We aimed to compare the effects of plasma glucose levels, plasma insulin levels and insulin resistance on the appearance of the AD-like pattern in 18F-FDG images. Methods Fifty-nine cognitively normal older subjects (age = 75.7 ± 6.4 years) underwent 18F-FDG positron emission tomography along with measurement of plasma glucose and insulin levels. As an index of insulin resistance, the Homeostasis model assessment of Insulin Resistance (HOMA-IR) was calculated. Results Plasma glucose levels, plasma insulin levels, and HOMA-IR were 102.2 ± 8.1 mg/dL, 4.1 ± 1.9 μU/mL, and 1.0 ± 0.5, respectively. Whole-brain voxelwise analysis showed a negative correlation of 18F-FDG uptake with plasma glucose levels in the precuneus and lateral parietotemporal regions (cluster-corrected p < 0.05), and no correlation with plasma insulin levels or HOMA-IR. In the significant cluster, 18F-FDG uptake decreased by approximately 4–5% when plasma glucose levels increased by 20 mg/dL. In the precuneus region, volume-of-interest analysis confirmed a negative correlation of 18F-FDG uptake with plasma glucose levels (r = -0.376, p = 0.002), and no correlation with plasma insulin levels (r = 0.156, p = 0.12) or HOMA-IR (r = 0.096, p = 0.24). Conclusion This study suggests that, of the three parameters, plasma glucose levels have the greatest effect on the appearance of the AD-like pattern in 18F-FDG images. PMID:28715453

  5. Effects of glucose, insulin, and insulin resistance on cerebral 18F-FDG distribution in cognitively normal older subjects.

    Directory of Open Access Journals (Sweden)

    Kenji Ishibashi

    Full Text Available Increasing plasma glucose levels and insulin resistance can alter the distribution pattern of fluorine-18-labeled fluorodeoxyglucose (18F-FDG in the brain and relatively reduce 18F-FDG uptake in Alzheimer's disease (AD-related hypometabolic regions, leading to the appearance of an AD-like pattern. However, its relationship with plasma insulin levels is unclear. We aimed to compare the effects of plasma glucose levels, plasma insulin levels and insulin resistance on the appearance of the AD-like pattern in 18F-FDG images.Fifty-nine cognitively normal older subjects (age = 75.7 ± 6.4 years underwent 18F-FDG positron emission tomography along with measurement of plasma glucose and insulin levels. As an index of insulin resistance, the Homeostasis model assessment of Insulin Resistance (HOMA-IR was calculated.Plasma glucose levels, plasma insulin levels, and HOMA-IR were 102.2 ± 8.1 mg/dL, 4.1 ± 1.9 μU/mL, and 1.0 ± 0.5, respectively. Whole-brain voxelwise analysis showed a negative correlation of 18F-FDG uptake with plasma glucose levels in the precuneus and lateral parietotemporal regions (cluster-corrected p < 0.05, and no correlation with plasma insulin levels or HOMA-IR. In the significant cluster, 18F-FDG uptake decreased by approximately 4-5% when plasma glucose levels increased by 20 mg/dL. In the precuneus region, volume-of-interest analysis confirmed a negative correlation of 18F-FDG uptake with plasma glucose levels (r = -0.376, p = 0.002, and no correlation with plasma insulin levels (r = 0.156, p = 0.12 or HOMA-IR (r = 0.096, p = 0.24.This study suggests that, of the three parameters, plasma glucose levels have the greatest effect on the appearance of the AD-like pattern in 18F-FDG images.

  6. Correlation of insulin resistance with serum C-reactive protein, adiponectin and leptin levels in patients with type 2 diabetes

    International Nuclear Information System (INIS)

    Duan Yangqiang; Wang Zuobing; Yu Hui

    2012-01-01

    Objective: To explore the relationship between serum C-reactive protein (CRP), adiponectin (APN), leptin (Leptin) levels, insulin resistance index (HOMA-IR) and type 2 diabetes mellitus (T2DM) disease susceptibility. Methods: The plasma leptin and insulin (FINS) levels in the DM patients were determined by RIA, and the serum ANP levels were determined by ELSIA. The CRP, conventional serum fasting plasma glucose (FPG) levels were determine by automatic biochemistry analyzer. The insulin resistance index (HOMA-IR, FPG x FINS/22.5) was calculated. The result was analyzed with normal healthy control group. Results: The serum CRP and leptin, HOMA-IR levels in T2DM group were significantly higher than that of in control group (P< 0.01), and the serum ANP was significantly lower than in control group (P<0.01). The HOMA-IR in T2DM was positively correlated with serum CRP (r= 0.36, P<0.05) and leptin(r= 0.39, P<0.05), and was negatively correlated with serum APN (r=0.32, P<0.05). Conclusion: The high serum CRP and leptin and low APN levels hyperlipidaemia might be factors for diabetes, and their metabolic disorders may be closely related with insulin resistance in patients with type 2 diabetes. (authors)

  7. Moderate alcohol consumption is associated with improved insulin sensitivity, reduced basal insulin secretion rate and lower fasting glucagon concentration in healthy women

    DEFF Research Database (Denmark)

    Bonnet, F; Disse, E; Laville, M

    2012-01-01

    Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes with a stronger effect in women. As the underlying mechanisms remain poorly characterised, we investigated its relationship with insulin resistance, insulin secretion, clearance of insulin and glucagon concentration....

  8. Prognostic value of insulin-like growth factor 1 and insulin-like growth factor binding protein 3 blood levels in breast cancer.

    NARCIS (Netherlands)

    Hartog, H.; Boezen, H.M.; Jong, M.M. de; Schaapveld, M.; Wesseling, J.; Graaf, W.T.A. van der

    2013-01-01

    High circulating insulin-like growth factor 1 (IGF-1) levels are firmly established as a risk factor for developing breast cancer, especially estrogen positive tumors. The effect of circulating IGF-1 on prognosis once a tumor is established is unknown. The authors explored the effect of IGF-1 blood

  9. Prognostic value of insulin-like growth factor 1 and insulin-like growth factor binding protein 3 blood levels in breast cancer

    NARCIS (Netherlands)

    Hartog, H; Boezen, H M; de Jong, M M; Schaapveld, M; Wesseling, J; van der Graaf, W T A

    2013-01-01

    High circulating insulin-like growth factor 1 (IGF-1) levels are firmly established as a risk factor for developing breast cancer, especially estrogen positive tumors. The effect of circulating IGF-1 on prognosis once a tumor is established is unknown. The authors explored the effect of IGF-1 blood

  10. Overexpression of Rad in muscle worsens diet-induced insulin resistance and glucose intolerance and lowers plasma triglyceride level

    Science.gov (United States)

    Ilany, Jacob; Bilan, Philip J.; Kapur, Sonia; Caldwell, James S.; Patti, Mary-Elizabeth; Marette, Andre; Kahn, C. Ronald

    2006-03-01

    Rad is a low molecular weight GTPase that is overexpressed in skeletal muscle of some patients with type 2 diabetes mellitus and/or obesity. Overexpression of Rad in adipocytes and muscle cells in culture results in diminished insulin-stimulated glucose uptake. To further elucidate the potential role of Rad in vivo, we have generated transgenic (tg) mice that overexpress Rad in muscle using the muscle creatine kinase (MCK) promoter-enhancer. Rad tg mice have a 6- to 12-fold increase in Rad expression in muscle as compared to wild-type littermates. Rad tg mice grow normally and have normal glucose tolerance and insulin sensitivity, but have reduced plasma triglyceride levels. On a high-fat diet, Rad tg mice develop more severe glucose intolerance than the wild-type mice; this is due to increased insulin resistance in muscle, as exemplified by a rightward shift in the dose-response curve for insulin stimulated 2-deoxyglucose uptake. There is also a unexpected further reduction of the plasma triglyceride levels that is associated with increased levels of lipoprotein lipase in the Rad tg mice. These results demonstrate a potential synergistic interaction between increased expression of Rad and high-fat diet in creation of insulin resistance and altered lipid metabolism present in type 2 diabetes. diabetes mellitus | glucose transport | RGK GTPase | transgenic mouse

  11. Diminished hepatic insulin removal in obesity

    International Nuclear Information System (INIS)

    Cano, I.; Salvador, J.; Rodriguez, R.; Arraiza, M.C.; Goena, M.; Barberia, J.J.; Moncada, E.

    1986-01-01

    Peripheral insulin and C-peptide levels during oral glucose load were measured in 20 obese and 23 normal weight nondiabetic subjects. The fasting C-peptide to insulin molar ratios (Cp/I), as well as the relation between incremental areas of the two polypeptides (ACp-AI)/ACp, were used as relative measures of the hepatic insulin extraction (HIE). The insulin and C-peptide basal levels as well as incremental areas under plasma curves were higher in the obese subjects (P<0.001). HIE was lower in obeses than in controls assessed in the fasting state (P<0.05), as well as after glucose load (P<0.001). Nevertheless, obeses and controls with similar insulin fasting levels showed identical hepatic insulin extraction in fasting or after glucose load. HIE was independent of obesity degree, but was related to insulin basal levels (r=-0.60, P<0.01). This study suggests the hypothesis that the decreased hepatic insulin extraction in obeses is a result of the chronically increased insulin delivery to the liver and is not a consequence of obesity, although a contributory role cannot be ruled out

  12. Diminished hepatic insulin removal in obesity

    Energy Technology Data Exchange (ETDEWEB)

    Cano, I; Salvador, J; Rodriguez, R; Arraiza, M C; Goena, M; Barberia, J J; Moncada, E

    1986-01-01

    Peripheral insulin and C-peptide levels during oral glucose load were measured in 20 obese and 23 normal weight nondiabetic subjects. The fasting C-peptide to insulin molar ratios (Cp/I), as well as the relation between incremental areas of the two polypeptides (ACp-AI)/ACp, were used as relative measures of the hepatic insulin extraction (HIE). The insulin and C-peptide basal levels as well as incremental areas under plasma curves were higher in the obese subjects (P<0.001). HIE was lower in obeses than in controls assessed in the fasting state (P<0.05), as well as after glucose load (P<0.001). Nevertheless, obeses and controls with similar insulin fasting levels showed identical hepatic insulin extraction in fasting or after glucose load. HIE was independent of obesity degree, but was related to insulin basal levels (r=-0.60, P<0.01). This study suggests the hypothesis that the decreased hepatic insulin extraction in obeses is a result of the chronically increased insulin delivery to the liver and is not a consequence of obesity, although a contributory role cannot be ruled out.

  13. High Uric Acid Induces Insulin Resistance in Cardiomyocytes In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Li Zhi

    Full Text Available Clinical studies have shown hyperuricemia strongly associated with insulin resistance as well as cardiovascular disease. Direct evidence of how high uric acid (HUA affects insulin resistance in cardiomyocytes, but the pathological mechanism of HUA associated with cardiovascular disease remains to be clarified. We aimed to examine the effect of HUA on insulin sensitivity in cardiomyocytes and on insulin resistance in hyperuricemic mouse model. We exposed primary cardiomyocytes and a rat cardiomyocyte cell line, H9c2 cardiomyocytes, to HUA, then quantified glucose uptake with a fluorescent glucose analog, 2-NBDG, after insulin challenge and detected reactive oxygen species (ROS production. Western blot analysis was used to examine the levels of insulin receptor (IR, phosphorylated insulin receptor substrate 1 (IRS1, Ser307 and phospho-Akt (Ser473. We monitored the impact of HUA on insulin resistance, insulin signaling and IR, phospho-IRS1 (Ser307 and phospho-Akt levels in myocardial tissue of an acute hyperuricemia mouse model established by potassium oxonate treatment. HUA inhibited insulin-induced glucose uptake in H9c2 and primary cardiomyocytes. It increased ROS production; pretreatment with N-acetyl-L-cysteine (NAC, a ROS scavenger, reversed HUA-inhibited glucose uptake induced by insulin. HUA exposure directly increased the phospho-IRS1 (Ser307 response to insulin and inhibited that of phospho-Akt in H9C2 cardiomyocytes, which was blocked by NAC. Furthermore, the acute hyperuricemic mice model showed impaired glucose tolerance and insulin tolerance accompanied by increased phospho-IRS1 (Ser307 and inhibited phospho-Akt response to insulin in myocardial tissues. HUA inhibited insulin signaling and induced insulin resistance in cardiomyocytes in vitro and in vivo, which is a novel potential mechanism of hyperuricemic-related cardiovascular disease.

  14. Clinical significance of determination of serum leptin, insulin levels and blood sugar in pregnant women with glucose metabolism disturbances

    International Nuclear Information System (INIS)

    Yu Suqing; Li Yusheng; Wang Lin; Chu Kaiqiu

    2006-01-01

    Objective: To investigate the changes of serum leptin, insulin levels and blood sugar contents in pregnant women with gestational glucose metabolism disturbances. Methods: Fasting and 3h after oral 50g glucose serum levels of leptin were measured with RIA in 36 pregnant women with glucose metabolism disturbances (gestational diabetes mellitus or gestational impaired glucose tolerance) and 34 controls. Also, fasting serum insulin levels (with CLIA) and blood sugar contents 1h after oral 50 glucose (with glucose oxidase method) were determined in all these subjects. Results: 1. Serum levels of leptin in pregnant women with glucose metabolism disturbances were 14.9 ± 4.3 μg/L (vs controls 9.8 ± 1.7 μg/L, P<0.01). 2. The serum levels of insulin and 1 h post - 50g glucose blood sugar contents in pregnant women with glucose metabolism disturbances were 12.9±4.3mU/L and 11.0±1.4mmol/L respectively, which were both significantly positively correlated with the serum leptin levels (r=0.835, r=0.758 respectively) (vs levels in controls: 8.45±3.0mU/L and 7.84±1.3mmol/L). Conclusion: Elevation of fasting serum levels of leptin was demonstrated in pregnant women with glucose metabolism disturbances and the level of leptin was positively correlated with that of insulin and blood sugar. (authors)

  15. Insulin autoimmune syndrome: case report

    Directory of Open Access Journals (Sweden)

    Rodrigo Oliveira Moreira

    Full Text Available CONTEXT: Insulin autoimmune syndrome (IAS, Hirata disease is a rare cause of hypoglycemia in Western countries. It is characterized by hypoglycemic episodes, elevated insulin levels, and positive insulin antibodies. Our objective is to report a case of IAS identified in South America. CASE REPORT: A 56-year-old Caucasian male patient started presenting neuroglycopenic symptoms during hospitalization due to severe trauma. Biochemical evaluation confirmed hypoglycemia and abnormally high levels of insulin. Conventional imaging examinations were negative for pancreatic tumor. Insulin antibodies were above the normal range. Clinical remission of the episodes was not achieved with verapamil and steroids. Thus, a subtotal pancreatectomy was performed due to the lack of response to conservative treatment and because immunosuppressants were contraindicated due to bacteremia. Histopathological examination revealed diffuse hypertrophy of beta cells. The patient continues to have high insulin levels but is almost free of hypoglycemic episodes.

  16. Genetic evidence of a causal effect of insulin resistance on branched-chain amino acid levels

    DEFF Research Database (Denmark)

    Mahendran, Yuvaraj; Jonsson, Anna; Have, Christian T

    2017-01-01

    variable for insulin resistance. A GRS of three variants increasing circulating BCAA levels was used as an instrumental variable for circulating BCAA levels. RESULTS: Fasting plasma BCAA levels were associated with higher HOMA-IR in ADDITION-PRO (β 0.137 [95% CI 0.08, 0.19] p = 6 × 10(-7)). However......, the GRS for circulating BCAA levels was not associated with fasting insulin levels or HOMA-IR in ADDITION-PRO (β -0.011 [95% CI -0.053, 0.032] p = 0.6 and β -0.011 [95% CI -0.054, 0.031] p = 0.6, respectively) or in GWAS results for HOMA-IR from MAGIC (β for valine-increasing GRS -0.012 [95% CI -0.069, 0......(-4), and β 0.67 [95% CI 0.16, 1.18] p = 0.01 for isoleucine, leucine and valine levels, respectively) and instrumental variable analyses in ADDITION-PRO indicated that HOMA-IR is causally related to higher circulating fasting BCAA levels (β 0.73 [95% CI 0.26, 1.19] p = 0.002). CONCLUSIONS/INTERPRETATION: Our...

  17. Effects of exercise training on glucose control, lipid metabolism, and insulin sensitivity in hypertriglyceridemia and non-insulin dependent diabetes mellitus.

    Science.gov (United States)

    Lampman, R M; Schteingart, D E

    1991-06-01

    Exercise training has potential benefits for patients with hyperlipidemia and/or non-insulin dependent diabetes mellitus. In nondiabetic, nonobese subjects with hypertriglyceridemia, exercise training alone increased insulin sensitivity, improved glucose tolerance, and lowered serum triglyceride and cholesterol levels. These improvements did not occur when exercise training alone was given to similar patients with impaired glucose tolerance. In severely obese (X = 125 kg) subjects without diabetes melitus, a 600 calorie diet alone decreased glucose and insulin concentrations and improved glucose tolerance but did not increase insulin sensitivity. The addition of exercise training improved insulin sensitivity. Obese, non-insulin dependent diabetes mellitus subjects on sulfonylurea therapy alone increased insulin levels but failed to improve insulin sensitivity or glucose levels. In contrast, the addition of exercise training to this medication resulted in improved insulin sensitivity and lowered glucose levels. We conclude that exercise training has major effects on lowering triglyceride levels in hyperlipidemic subjects and can potentiate the effect of diet or drug therapy on glucose metabolism in patients with non-insulin dependent diabetes mellitus.

  18. Muscle insulin binding and plasma levels in relation to liver glucokinase activity, glucose metabolism and dietary carbohydrates in rainbow trout.

    Science.gov (United States)

    Capilla, Encarnación; Médale, Françoise; Navarro, Isabel; Panserat, Stéphane; Vachot, Christiane; Kaushik, Sadasivam; Gutiérrez, Joaquim

    2003-01-31

    Rainbow trout were fed for 10 weeks with either a carbohydrate-free diet (C-free) or with four experimental diets containing various levels (20 or 40%) and sources of starch (extruded wheat or peas) in order to examine metabolic utilisation of dietary vegetable carbohydrates and its endocrine control. The study was focused on the parameters described as limiting in glucose metabolism in fish. Feeding trials were conducted at 8 and 18 degrees C to establish whether carbohydrate-rich diets can be used in trout farming irrespective of water temperature. At both temperatures, pea diets (especially the highest level) resulted in a feed efficiency as high as the C-free diet. Fish had similar growth rates except when fed the low wheat content diet. Glycaemia values 6 h after feeding were significantly higher in trout fed carbohydrate diets than those given the C-free diet, whereas plasma insulin levels were similar independently of the levels of dietary starch. This study provides the first evidence that glucokinase (GK) activity and mRNA level in trout liver increase in proportion to the content of dietary starch. Nevertheless, these changes were not correlated with plasma insulin levels. Insulin-like growth factor-I (IGF-I) binding and number of receptors in skeletal muscle were consistently higher than those for insulin but no diet-induced differences were found for any of these parameters. Temperature clearly affected the postprandial profile of glucose and insulin, which both showed lower levels 6 h after feeding at 8 degrees C than at 18 degrees C, which was consistent with a lower feed intake. Glucose and insulin levels decreased markedly 24 h after feeding at 18 degrees C, while they were still high at 8 degrees C, an observation concordant with delayed transit rate. These findings indicate satisfactory adaptation of rainbow trout to diets with a relatively high vegetable starch content, especially when provided as extruded peas, and indicate that diets with

  19. Hyperinsulinemic hypoglycemia associated with insulin antibodies caused by exogenous insulin analog

    Directory of Open Access Journals (Sweden)

    Chih-Ting Su

    2016-11-01

    Full Text Available Insulin antibodies (IA associated with exogenous insulin administration seldom caused hypoglycemia and had different characteristics from insulin autoantibodies (IAA found in insulin autoimmune syndrome (IAS, which was first described by Dr Hirata in 1970. The characteristic of IAS is the presence of insulin-binding autoantibodies and related fasting or late postprandial hypoglycemia. Here, we report a patient with type 1 diabetes mellitus under insulin glargine and insulin aspart treatment who developed recurrent spontaneous post-absorptive hyperinsulinemic hypoglycemia with the cause probably being insulin antibodies induced by exogenous injected insulin. Examinations of serial sera disclosed a high titre of insulin antibodies (33%, normal <5%, high insulin concentration (111.9 IU/mL and undetectable C-peptide when hypoglycemia occurred. An oral glucose tolerance test revealed persistent high serum levels of total insulin and undetectable C-peptide. Image studies of the pancreas were unremarkable, which excluded the diagnosis of insulinoma. The patient does not take any of the medications containing sulfhydryl compounds, which had been reported to cause IAS. After administering oral prednisolone for 3 weeks, hypoglycemic episodes markedly improved, and he was discharged smoothly.

  20. Glycogen synthase and phosphofructokinase protein and mRNA levels in skeletal muscle from insulin-resistant patients with non-insulin-dependent diabetes mellitus

    DEFF Research Database (Denmark)

    Vestergaard, H; Lund, S; Larsen, F S

    1993-01-01

    In patients with non-insulin-dependent diabetes mellitus (NIDDM) and matched control subjects we examined the interrelationships between in vivo nonoxidative glucose metabolism and glucose oxidation and the muscle activities, as well as the immunoreactive protein and mRNA levels of the rate-limit...

  1. The impaired change in plasma long-chain acylcarnitine level as a marker of insulin resistence

    OpenAIRE

    Šišmová, Petra

    2018-01-01

    Charles University Faculty of Pharmacy in Hradec Kralove Department of Biophysics and Physical Chemistry Rīga Stradiņš University Latvian Institute of Organic Synthesis Laboratory of Pharmaceutical Pharmacology Candidate: Petra Šišmová Supervisor: Dr. Pharm. Elina Makarova, assoc. prof. Veronika Nováková, Ph.D. Title of the diploma thesis: The impaired change in plasma long-chain acylcarnitine level as a marker of insulin resistance Insulin resistance presents one of the factors that could le...

  2. Insulin induces airway smooth muscle contraction

    NARCIS (Netherlands)

    Schaafsma, D.; Gosens, R.; Ris, J. M.; Zaagsma, J.; Meurs, H.; Nelemans, S. A.

    Background and purpose: Recently, the use of inhaled insulin formulations for the treatment of type I and type II diabetes has been approved in Europe and in the United States. For regular use, it is critical that airway function remains unimpaired in response to insulin exposure. Experimental

  3. Starvation increases insulin sensitivity and reduces juvenile hormone synthesis in mosquitoes.

    Directory of Open Access Journals (Sweden)

    Meritxell Perez-Hedo

    Full Text Available The interactions between the insulin signaling pathway (ISP and juvenile hormone (JH controlling reproductive trade-offs are well documented in insects. JH and insulin regulate reproductive output in mosquitoes; both hormones are involved in a complex regulatory network, in which they influence each other and in which the mosquito's nutritional status is a crucial determinant of the network's output. Previous studies reported that the insulin-TOR (target of rapamacyn signaling pathway is involved in the nutritional regulation of JH synthesis in female mosquitoes. The present studies further investigate the regulatory circuitry that controls both JH synthesis and reproductive output in response to nutrient availability.We used a combination of diet restriction, RNA interference (RNAi and insulin treatments to modify insulin signaling and study the cross-talk between insulin and JH in response to starvation. JH synthesis was analyzed using a newly developed assay utilizing fluorescent tags.Our results reveal that starvation decreased JH synthesis via a decrease in insulin signaling in the corpora allata (CA. Paradoxically, starvation-induced up regulation of insulin receptor transcripts and therefore "primed" the gland to respond rapidly to increases in insulin levels. During this response to starvation the synthetic potential of the CA remained unaffected, and the gland rapidly and efficiently responded to insulin stimulation by increasing JH synthesis to rates similar to those of CA from non-starved females.

  4. Alteration of serum tumor necrosis factor-alpha level in gestational diabetes mellitus and correlation with insulin resistance

    International Nuclear Information System (INIS)

    Zou Gang; Li Cuiyin; Shao Hao; Lu Zeyuan; Lai Liping; Liu Lan; Hu Xiaorong

    2009-01-01

    Objective: To explore the dynamic of tumor necrosis factor-alpha (TNF-α)and its correlation with insulin resistance (IR)during different stages of gestational diabetes mellitus (GDM). Methods: Thirty-two subjects with GDM and 31 cases of normal pregnant women nonnal glucose tolerance, NGT were enrolled in the study, serum TNF-α and insulin were determined by radioimmunoassay. The plasma glucose was measured by using glucose oxidase. Tests repeated for each group according different stages of prenatal 25-28 weeks, 29-32 weeks, 37-38 weeks and postpartum 6-8 weeks. IR was assessed by the homeostasis model of assessment for insulin resistance index (HOMA-IR). Results: (1)Serum TNF-α levels in CDM and NGT group rose with gestational age, and both significantly decreased at postpartum. (2) Serum TNF-α levels in GDM of above-mentioned four stages respectively were (7.05±0.67) ng/L, (7.11± 0.75) ng/L, (7.36±0.79) ng/L, (5.46±0.37) ng/L respectively. All significantly increased than those in the same stage group (t=7.81, 7.05, 7.15, P<0.01). (3) Maternal serum TNF-α levels were in positive correlation with HOMA-IR in GDM (r=0.571, P<0.05). Conclusions: Serum TNF-α levels in GDM rose with gestational age, but significantly decreased at postpartum. The dynamic changes of serum TNF-α contribute to occurrence of insulin resistance. (authors)

  5. Sustained Treatment with Insulin Detemir in Mice Alters Brain Activity and Locomotion.

    Directory of Open Access Journals (Sweden)

    Tina Sartorius

    Full Text Available Recent studies have identified unique brain effects of insulin detemir (Levemir®. Due to its pharmacologic properties, insulin detemir may reach higher concentrations in the brain than regular insulin. This might explain the observed increased brain stimulation after acute insulin detemir application but it remained unclear whether chronic insulin detemir treatment causes alterations in brain activity as a consequence of overstimulation.In mice, we examined insulin detemir's prolonged brain exposure by continuous subcutaneous (s.c. application using either micro-osmotic pumps or daily s.c. injections and performed continuous radiotelemetric electrocorticography and locomotion recordings.Acute intracerebroventricular injection of insulin detemir activated cortical and locomotor activity significantly more than regular insulin in equimolar doses (0.94 and 5.63 mU in total, suggesting an enhanced acute impact on brain networks. However, given continuously s.c., insulin detemir significantly reduced cortical activity (theta: 21.3±6.1% vs. 73.0±8.1%, P<0.001 and failed to maintain locomotion, while regular insulin resulted in an increase of both parameters.The data suggest that permanently-increased insulin detemir levels in the brain convert its hyperstimulatory effects and finally mediate impairments in brain activity and locomotion. This observation might be considered when human studies with insulin detemir are designed to target the brain in order to optimize treatment regimens.

  6. Sudden improvement of insulin sensitivity related to an endodontic treatment.

    Science.gov (United States)

    Schulze, A; Schönauer, M; Busse, M

    2007-12-01

    Inflammation contributes to the pathogenesis of diabetes. A reciprocal relationship exists between diabetes and chronic periodontitis. This report describes the effects of an acute focal dental inflammation and subsequent endodontic treatment on the required insulin dosage of a 70-year-old man who had moderately controlled diabetes. Following an exacerbation of a combined endodontic-periodontic (endo-perio) lesion of tooth #3, the patient noticed a sudden increase in his insulin demand. After 3 weeks, the required dosage was approximately 100% greater. In association with hyperglycemic incidents, he reported a prickling sensation in this tooth. The radiograph showed circular bone loss around the tooth. Just 1 day after the root-canal preparation, the insulin need decreased to approximately 50% of that required prior to treatment. Subsequently, an incision and systemic antibiotics were necessary because of the formation of a periodontal abscess. The insulin demand remained low despite this complication. Forty days after endodontic treatment, the insulin dosage was at a level comparable to that taken 4 weeks before the root-canal preparation. This clinical case revealed a highly relevant correlation between insulin resistance and a local dental inflammation. To avoid an increase in insulin resistance, it seems important to attend to radically non-vital teeth as well as any other dental inflammation in diabetic patients.

  7. Insulin analogues and severe hypoglycaemia in type 1 diabetes

    DEFF Research Database (Denmark)

    Kristensen, P L; Hansen, L S; Jespersen, M J

    2012-01-01

    The effect of insulin analogues on glycaemic control is well-documented, whereas the effect on avoidance of severe hypoglycaemia remains tentative. We studied the frequency of severe hypoglycaemia in unselected patients with type 1 diabetes treated with insulin analogues, human insulin, or mixed...

  8. [Molecular mechanism for ET-1-induced insulin resistance in skeletal muscle cells].

    Science.gov (United States)

    Horinouchi, Takahiro; Mazaki, Yuichi; Terada, Koji; Miwa, Soichi

    2018-01-01

    Insulin resistance is a condition where the sensitivity to insulin of the tissues expressing insulin receptor (InsR) is decreased due to a functional disturbance of InsR-mediated intracellular signaling. Insulin promotes the entry of glucose into the tissues and skeletal muscle is the most important tissue responsible for the insulin's action of decreasing blood glucose levels. Endothelin-1 (ET-1), a potent vasoconstrictor and pro-inflammatory peptide, induces insulin resistance through a direct action on skeletal muscle. However, the signaling pathways of ET-1-induced insulin resistance in skeletal muscle remain unclear. Here we show molecular mechanism underlying the inhibitory effect of ET-1 on insulin-stimulated Akt phosphorylation and glucose uptake in myotubes of rat L6 skeletal muscle cell line. mRNA expression levels of differentiation marker genes, MyoD and myogenin, were increased during L6 myoblasts differentiation into myotubes. Some of myotubes possessed the ability to spontaneously contract. In myotubes, insulin promoted Akt phosphorylation at Thr 308 and Ser 473 , and [ 3 H]-labelled 2-deoxy-D-glucose ([ 3 H]2-DG) uptake. The insulin-facilitated Akt phosphorylation and [ 3 H]2-DG uptake were inhibited by ET-1. The inhibitory effect of ET-1 was counteracted by blockade of ET type A receptor (ET A R), inhibition of G q/11 protein, and siRNA knockdown of G protein-coupled receptor kinase 2 (GRK2). The exogenously overexpressed GRK2 directly bound to endogenous Akt and their association was facilitated by ET-1. In summary, activation of ET A R with ET-1 inhibits insulin-induced Akt phosphorylation and [ 3 H]2-DG uptake in a G q/11 protein- and GRK2-dependent manner in skeletal muscle. These findings indicate that ET A R and GRK2 are potential targets for insulin resistance.

  9. Mono-2-ethylhexyl phthalate associated with insulin resistance and lower testosterone levels in a young population.

    Science.gov (United States)

    Chen, Szu-Ying; Hwang, Jing-Shiang; Sung, Fung-Chang; Lin, Chien-Yu; Hsieh, Chia-Jung; Chen, Pau-Chung; Su, Ta-Chen

    2017-06-01

    Phthalates are commonly used as plasticizers and are reported to associate with testicular dysfunction or insulin resistance in different studies, but the concurrent relationship between phthalate exposure, testosterone levels, and insulin resistance in the young population is not well understood. We recruited 786 subjects aged 12-30 years from a population-based sample of Taiwanese adolescents and young adults from 2006 to 2008. Generalized additive models were used to evaluate glucose homeostasis and testicular function in relation to seven urinary phthalate metabolites among adolescents (aged 12-20) and young adults (aged 20-30) in Taiwan. We observed a trend toward a decrease in male testosterone and an increase in urinary mono-2-ethylhexyl phthalate (MEHP) levels across four quartiles of homeostasis model assessment of insulin resistance (HOMA-IR). After adjusting for potential covariates, generalized additive models further showed that log-transformed insulin and HOMA-IR were raised by 0.055 [95% confidence interval (CI), 0.027-0.082] and 0.056 (95% CI, 0.027-0.084), respectively, with a one-unit increase in log-transformed MEHP in young adults. In male adults (aged 22-30), the log-testosterone levels were reduced by 0.018 (95% CI, 0.001-0.036), with a one-unit of increase in log-transformed MEHP. Such relationships were not observed in adolescents. In conclusion, this study demonstrated age-related associations of urinary MEHP metabolites with impaired metabolic homeostasis of glucose that were only observed in young adults. In addition, MEHP exposure was concurrently associated with lower testosterone levels in young, male adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Role of insulin in the hyperandrogenemia of lean women with polycystic ovary syndrome and normal insulin sensitivity.

    Science.gov (United States)

    Baillargeon, Jean-Patrice; Carpentier, André

    2007-10-01

    To determine the effect of reducing insulin secretion on hyperandrogenemia in lean normoinsulinemic women with polycystic ovary syndrome (PCOS) and normal metabolic insulin sensitivity. Transversal assessment at baseline and prospective follow-up of lean PCOS group after 8 days of diazoxide, which reduces insulin secretion, and 1 month of leuprolide, which suppresses LH. Clinical research center of an academic hospital. Nine lean women (body mass index PCOS and normal insulin levels, as well as 17 lean healthy women. Lean PCOS women were reassessed after 8 days of diazoxide and after 1 month of leuprolide, which suppresses LH. Androgen levels and insulin-stimulated glucose disposal (metabolic insulin sensitivity), determined by euglycemic-hyperinsulinemic clamp (M-value). Mean M-value of lean PCOS women (48.5 micromol/kg.min) was similar to lean control subjects (52.9 micromol/kg.min). They also had comparable anthropometric measures, lipids, fibrinogen, and plasminogen activator inhibitor 1. The LH did not change significantly after diazoxide, but was almost suppressed after leuprolide in the PCOS group. Androstenedione decreased significantly after diazoxide and even more after leuprolide. However, free T significantly decreased only after diazoxide in lean PCOS women. Diazoxide also increased SHBG significantly in this group. In women with typical PCOS and normal insulin levels and metabolic insulin sensitivity, reducing insulin secretion significantly decreased androgen and increased SHBG levels. These results suggest that insulin contributes to hyperandrogenemia even in PCOS women with normal metabolic insulin sensitivity, which might be due to increased sensitivity of their androgenic insulin pathway.

  11. Intraportal injection of insulin-producing cells generated from human bone marrow mesenchymal stem cells decreases blood glucose level in diabetic rats.

    Science.gov (United States)

    Tsai, Pei-Jiun; Wang, Hwai-Shi; Lin, Chi-Hung; Weng, Zen-Chung; Chen, Tien-Hua; Shyu, Jia-Fwu

    2014-01-01

    We studied the process of trans-differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs) into insulin-producing cells. Streptozotocin (STZ)-induced diabetic rat model was used to study the effect of portal vein transplantation of these insulin-producing cells on blood sugar levels. The BM-MSCs were differentiated into insulin-producing cells under defined conditions. Real-time PCR, immunocytochemistry and glucose challenge were used to evaluate in vitro differentiation. Flow cytometry showed that hBM-MSCs were strongly positive for CD44, CD105 and CD73 and negative for hematopoietic markers CD34, CD38 and CD45. Differentiated cells expressed C-peptide as well as β-cells specific genes and hormones. Glucose stimulation increased C-peptide secretion in these cells. The insulin-producing, differentiated cells were transplanted into the portal vein of STZ-induced diabetic rats using a Port-A catheter. The insulin-producing cells were localized in the liver of the recipient rat and expressed human C-peptide. Blood glucose levels were reduced in diabetic rats transplanted with insulin-producing cells. We concluded that hBM-MSCs could be trans-differentiated into insulin-producing cells in vitro. Portal vein transplantation of insulin-producing cells alleviated hyperglycemia in diabetic rats.

  12. Blood Glucose and Insulin Concentrations after Octreotide Administration in Horses With Insulin Dysregulation.

    Science.gov (United States)

    Frank, N; Hermida, P; Sanchez-Londoño, A; Singh, R; Gradil, C M; Uricchio, C K

    2017-07-01

    Octreotide is a somatostatin analog that suppresses insulin secretion. We hypothesized that octreotide would suppress insulin concentrations in horses and that normal (N) horses and those with insulin dysregulation (ID) would differ significantly in their plasma glucose and insulin responses to administration of octreotide. Twelve horses, N = 5, ID = 7. Prospective study. An oral sugar test was performed to assign horses to N and ID groups. Octreotide (1.0 μg/kg IV) was then administered, and blood was collected at 0, 5, 10, 15, 20, 25, 30, 45, 60, 75, and 90 minute, and 2, 3, 4, 6, 8, 12, and 24 hour for measurement of glucose and insulin concentrations. Area under the curve (AUC) values were calculated. Mean AUC values for glucose and insulin did not differ between normal (n = 5) and ID (n = 7) groups after octreotide injection. Significant time (P glucose and insulin concentrations. A group × time interaction (P = .091) was detected for insulin concentrations after administration of octreotide, but the group (P = .33) effect was not significant. Octreotide suppresses insulin secretion, resulting in hyperglycemia, and then concentrations increase above baseline as glycemic control is restored. Our hypothesis that octreotide causes insulin concentrations to decrease in horses was supported, but differences between N and ID groups did not reach statistical significance when blood glucose and insulin responses were compared. The utility of an octreotide response test remains to be determined. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  13. Lipid metabolism disturbances contribute to insulin resistance and decrease insulin sensitivity by malathion exposure in Wistar rat.

    Science.gov (United States)

    Lasram, Mohamed Montassar; Bouzid, Kahena; Douib, Ines Bini; Annabi, Alya; El Elj, Naziha; El Fazaa, Saloua; Abdelmoula, Jaouida; Gharbi, Najoua

    2015-04-01

    Several studies showed that organophosphorus pesticides disturb glucose homeostasis and can increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on glucose metabolism regulation, in vivo, during subchronic exposure. Malathion was administered orally (200 mg/kg), once a day for 28 consecutive days. Plasma glucose, insulin and Glycated hemoglobin levels were significantly increased while hepatic glycogen content was decreased in intoxicated animals compared with the control group. Furthermore, there was a significant disturbance of lipid content in subchronic treated and post-treated rats deprived of malathion for one month. In addition, we used the homeostasis model assessment (HOMA) to assess insulin resistance (HOMA-IR) and pancreatic β-cell function (HOMA-β). Our results show that malathion increases insulin resistance biomarkers and decreases insulin sensitivity indices. Statistical analysis demonstrates that there was a positive and strong significant correlation between insulin level and insulin resistance indices, HOMA-IR, HOMA-β. Similarly, a negative and significant correlation was also found between insulin level and insulin sensitivity indices. For the first time, we demonstrate that malathion induces insulin resistance in vivo using homeostasis model assessment and these changes were detectable one month after the end of exposure. To explain insulin resistance induced by malathion we focus on lipid metabolism disturbances and their interaction with many proteins involved in insulin signaling pathways.

  14. Serum IGF1 and insulin levels in girls with normal and precocious puberty

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Aksglaede, Lise; Petersen, Jørgen Holm

    2012-01-01

    IGF1 plays an important role in growth and metabolism during puberty. IGF1 levels are increased in girls with central precocious puberty (CPP). However, the relationship with insulin before and during gonadal suppression is unknown. In addition, the influence of the exon 3-deleted GH receptor gene...

  15. Effects of 12-weeks physical activity and omega-3 supplementation on serum ghrelin and insulin levels in young women

    Directory of Open Access Journals (Sweden)

    Eskandar Rahimi

    2014-05-01

    Full Text Available Background: Normal levels of ghrelin and insulin hormones play an important role in energy-balance, weight control and preventing type 2 diabetes. The purpose of this study was to evaluate the effects of twelve weeks physical activity with omega-3 supplementation consumption on insulin and ghrelin hormones in young women. Materials and methods: In this semi-experimental study 60 young women aged 19-25 years randomly divided into four groups including. (Exercise with supplementation, exercise alone, supplementation alone and control group. Exercise group and exercise- supplementation group followed the basketball training for 12 weeks under the supervision of skillful trainers. Supplementation group and exercise- supplementation group were asked to take 3gram omega-3 capsules per day for 12 weeks. Anthropometric indicators and blood samples were obtained in the morning after an 8-12 hr fast prior to the start of the study and again 12weeks after at the end of the study under the same conditions to measure plasma ghrelin and insulin hormones (Elisa method. Data analysis using tests of Kolmogorov-Smirnov t-test, one-way analysis of variance (ANOVA conducted through SPSS-16 software. Results: The results of ANOVA test showed that after 12 weeks of study ghrelin and insulin levels in exercise-supplement group, (P=0.000, P=0.000, exercise group (P=0.000, P=0.000, and supplement group (P=0.044, P=0.017 significantly increase and decrease respectively. But no significant changes were observed in control group for ghrelin (P=0.740 and insulin (P= 0.108 levels before and after the study. Conclusion: Based on the results of this study, physical activity with omega-3 supplementation can create significant changes on the levels of ghrelin and insulin hormones in young women. These changes may help to control and prevent diabetes and its, complications.

  16. APPL1 potentiates insulin sensitivity by facilitating the binding of IRS1/2 to the insulin receptor.

    Science.gov (United States)

    Ryu, Jiyoon; Galan, Amanda K; Xin, Xiaoban; Dong, Feng; Abdul-Ghani, Muhammad A; Zhou, Lijun; Wang, Changhua; Li, Cuiling; Holmes, Bekke M; Sloane, Lauren B; Austad, Steven N; Guo, Shaodong; Musi, Nicolas; DeFronzo, Ralph A; Deng, Chuxia; White, Morris F; Liu, Feng; Dong, Lily Q

    2014-05-22

    Binding of insulin receptor substrate proteins 1 and 2 (IRS1/2) to the insulin receptor (IR) is essential for the regulation of insulin sensitivity and energy homeostasis. However, the mechanism of IRS1/2 recruitment to the IR remains elusive. Here, we identify adaptor protein APPL1 as a critical molecule that promotes IRS1/2-IR interaction. APPL1 forms a complex with IRS1/2 under basal conditions, and this complex is then recruited to the IR in response to insulin or adiponectin stimulation. The interaction between APPL1 and IR depends on insulin- or adiponectin-stimulated APPL1 phosphorylation, which is greatly reduced in insulin target tissues in obese mice. appl1 deletion in mice consistently leads to systemic insulin resistance and a significant reduction in insulin-stimulated IRS1/2, but not IR, tyrosine phosphorylation, indicating that APPL1 sensitizes insulin signaling by acting at a site downstream of the IR. Our study uncovers a mechanism regulating insulin signaling and crosstalk between the insulin and adiponectin pathways. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Carbohydrate-to-insulin ratio is estimated from 300-400 divided by total daily insulin dose in type 1 diabetes patients who use the insulin pump.

    Science.gov (United States)

    Kuroda, Akio; Yasuda, Tetsuyuki; Takahara, Mitsuyoshi; Sakamoto, Fumie; Kasami, Ryuichi; Miyashita, Kazuyuki; Yoshida, Sumiko; Kondo, Eri; Aihara, Ken-ichi; Endo, Itsuro; Matsuoka, Taka-aki; Kaneto, Hideaki; Matsumoto, Toshio; Shimomura, Iichiro; Matsuhisa, Munehide

    2012-11-01

    To optimize insulin dose using insulin pump, basal and bolus insulin doses are widely calculated from total daily insulin dose (TDD). It is recommended that total daily basal insulin dose (TBD) is 50% of TDD and that the carbohydrate-to-insulin ratio (CIR) equals 500 divided by TDD. We recently reported that basal insulin requirement is approximately 30% of TDD. We therefore investigated CIR after adjustment of the proper basal insulin rate. Forty-five Japanese patients with type 1 diabetes were investigated during several weeks of hospitalization. The patients were served standard diabetes meals (25-30 kcal/kg of ideal body weight). Each meal omission was done to confirm basal insulin rate. Target blood glucose level was set at 100 and 150 mg/dL before and 2 h after each meal, respectively. After the basal insulin rate was fixed and target blood glucose levels were achieved, TBD, CIR, TDD, and their products were determined. Mean (±SD) blood glucose levels before and 2 h after meals were 121±47 and 150±61 mg/dL, respectively. TDD was 31.5±9.0 U, and TBD was 27.0±6.5% of TDD. CIR×TDD of breakfast was significantly lower than those of lunch and supper (288±73 vs. 408±92 and 387±83, respectively; Plunch and supper in type 1 diabetes patients. These results indicate that the insulin dose has been underestimated by using previously established calculations.

  18. Relationship of serum resistin with insulin resistance and obesity

    International Nuclear Information System (INIS)

    Zaidi, S.I.Z.

    2015-01-01

    Background: Adipokines have been implicated in the modulation of insulin sensitivity and glucose tolerance and have thus gained importance in the study of Type 2 diabetes mellitus (T2DM). Resistin, a unique signalling molecule, is being proposed as a significant factor in the pathogenesis of obesity-related insulin resistance. However, its relevance to human diabetes mellitus remains uncertain and controversial. This study was therefore planned to compare and correlate the potential role of resistin in obese patients with T2DM and obese non-diabetic controls and also to evaluate the correlation between resistin and marker of obesity and glycaemic parameters. Method: Fasting serum resistin, glucose and insulin were measured in forty obese diabetics (mean±SD BMI 35±5 kg/m2) and forty obese non-diabetics (mean±SD BMI 33±3 kg/m2). Insulin resistance was assessed using the HOMA-IR formula derived from fasting insulin and glucose levels. Results: Serum resistin levels (38±8 ng/ml) were significantly higher in type 2 diabetic patients as compared with the controls. Fasting blood glucose (164±46 mg/dl), serum insulin (37±7 μU/ml) and insulin resistance (19±8), were considerably higher among the studied diabetics than in the controls. Pearson's correlation analysis revealed positive correlation between serum resistin and BMI (p=0.001) and HOMA-IR (p=0.561) in diabetic subjects. Similarly, a correlation also existed between serum resistin and BMI (p=0.016) and HOMA-IR (p=0.307) in control obese subjects. However, it was highly significant in diabetics as compared to non-diabetic controls. Conclusion: A significant BMI-dependent association exists between resistin and insulin resistance in patients with T2DM. It appears that resistin may play a role in the pathogenesis of obesity and insulin resistance and that both of these may contribute to the development of T2DM. (author)

  19. Intranasal Insulin Restores Metabolic Parameters and Insulin Sensitivity in Rats with Metabolic Syndrome.

    Science.gov (United States)

    Derkach, K V; Ivantsov, A O; Chistyakova, O V; Sukhov, I B; Buzanakov, D M; Kulikova, A A; Shpakov, A O

    2017-06-01

    We studied the effect of 10-week treatment with intranasal insulin (0.5 IU/day) on glucose tolerance, glucose utilization, lipid metabolism, functions of pancreatic β cells, and insulin system in the liver of rats with cafeteria diet-induced metabolic syndrome. The therapy reduced body weight and blood levels of insulin, triglycerides, and atherogenic cholesterol that are typically increased in metabolic syndrome, normalized glucose tolerance and its utilization, and increased activity of insulin signaling system in the liver, thus reducing insulin resistance. The therapy did not affect the number of pancreatic islets and β cells. The study demonstrates prospects of using intranasal insulin for correction of metabolic parameters and reduction of insulin resistance in metabolic syndrome.

  20. Acacia nilotica leave extract and glyburide: comparison of fasting flood glucose, serum insulin, b-thromboglubulin levels and platelet aggregation in treptozotocin induced diabetic rats

    International Nuclear Information System (INIS)

    Asad, M.; Munir, T.A.; Afzal, N.

    2011-01-01

    Objectives: To evaluate the hypoglycaemic and anti-platelet aggregation effect of aqueous methanol extract of Acacia Nilotica (AN) leaves compared with glyburide on streptozotocin induced diabetic rats. Methods: Diabetes mellitus was induced in 90 out of 120 albino rats by administering 50 mg/kg body weight (b.w) streptozotocin and was confirmed by measuring fasting blood glucose level >200 mg/dL on fourth post-induction day. The rats were equally divided into 4 groups, A (normal control), B (diabetic control), C (diabetic rats treated with AN extract) and group D (diabetic rats treated with glyburide). The rats of group C and D were given 300 mg/kg b.w AN extract and 900 mu gm/kg b.w glyburide respectively for 3 weeks. Blood glucose was measured by gluco meter, platelet aggregation by Dia-Med method and insulin and b-thrombo globulin by ELISA technique. Results: A significant increase (p<0.05) in fasting blood glucose, b-thrombo globulin and platelet aggregation and a significant decrease (p<0.05) in insulin levels was observed in streptozotocin induced diabetic rats than the normal controls. The rats treated with AN extract and glyburide showed a significant decrease (p<0.05) in fasting blood glucose and increase (p<0.05) in insulin levels than the diabetic control rats. However, the levels in both the treatment groups remained significantly different than the normal controls. A significant decrease (p<0.05) in b-thrombo globulin levels was seen in diabetic rats treated with glyburide than the diabetic control rats and diabetic rats treated with AN extract. Conclusions: AN leaves extract result into hypoglycaemic and anti-platelet aggregation activity in diabetic rats as that of glyburide. (author)

  1. Elevated plasma SPARC levels are associated with insulin resistance, dyslipidemia, and inflammation in gestational diabetes mellitus.

    Directory of Open Access Journals (Sweden)

    Lu Xu

    Full Text Available OBJECTIVE: Recent studies suggested that secreted protein acidic and rich in cysteine (SPARC, a novel adipokine, is a key player in the pathology of obesity and type 2 diabetes. We aimed to determine whether concentrations of SPARC were altered in patients with gestational diabetes mellitus (GDM compared to normal glucose tolerance (NGT controls and to investigate the relationships between SPARC and metabolic parameters in pregnant women. DESIGN/METHODS: Cross-sectional study of 120 pregnant women with GDM and 60 controls with NGT, in a university hospital setting. Plasma levels of SPARC, adiponectin, fibroblast growth factor 21 (FGF21, insulin and proinsulin were determined by ELISA. RESULTS: GDM women had higher SPARC and lower adiponectin than NGT subjects; no difference was found in FGF21. SPARC levels were the lowest in subjects in the third tertile of insulin sensitivity index (ISIOGTT and correlated positively with pre-pregnant BMI, insulin and 3 h glucose during 100-g OGTT, HOMA-IR, fasting proinsulin, hsCRP and white blood cells count, and negatively with ISIOGTT, when adjusting for gestational age. Triglyceride (TG, Apolipoprotein A1, apolipoprotein B and lipoprotein (a correlated with SPARC in partial Pearson correlation. Correlations between SPARC with adiponectin, systolic blood pressure and TG were marginally significant in partial Spearman correlation analysis. In multivariate regression analysis, SPARC was an independent negative indicator of ISIOGTT. CONCLUSIONS: SPARC levels are correlated significantly with inflammation and may also be correlated with dyslipidemia and represent an independent determinant of insulin resistance in late pregnancy, indicating a potential role of SPARC in the pathophysiology of GDM.

  2. Elevated plasma SPARC levels are associated with insulin resistance, dyslipidemia, and inflammation in gestational diabetes mellitus.

    Science.gov (United States)

    Xu, Lu; Ping, Fan; Yin, Jinhua; Xiao, Xinhua; Xiang, Hongding; Ballantyne, Christie M; Wu, Huaizhu; Li, Ming

    2013-01-01

    Recent studies suggested that secreted protein acidic and rich in cysteine (SPARC), a novel adipokine, is a key player in the pathology of obesity and type 2 diabetes. We aimed to determine whether concentrations of SPARC were altered in patients with gestational diabetes mellitus (GDM) compared to normal glucose tolerance (NGT) controls and to investigate the relationships between SPARC and metabolic parameters in pregnant women. Cross-sectional study of 120 pregnant women with GDM and 60 controls with NGT, in a university hospital setting. Plasma levels of SPARC, adiponectin, fibroblast growth factor 21 (FGF21), insulin and proinsulin were determined by ELISA. GDM women had higher SPARC and lower adiponectin than NGT subjects; no difference was found in FGF21. SPARC levels were the lowest in subjects in the third tertile of insulin sensitivity index (ISIOGTT) and correlated positively with pre-pregnant BMI, insulin and 3 h glucose during 100-g OGTT, HOMA-IR, fasting proinsulin, hsCRP and white blood cells count, and negatively with ISIOGTT, when adjusting for gestational age. Triglyceride (TG), Apolipoprotein A1, apolipoprotein B and lipoprotein (a) correlated with SPARC in partial Pearson correlation. Correlations between SPARC with adiponectin, systolic blood pressure and TG were marginally significant in partial Spearman correlation analysis. In multivariate regression analysis, SPARC was an independent negative indicator of ISIOGTT. SPARC levels are correlated significantly with inflammation and may also be correlated with dyslipidemia and represent an independent determinant of insulin resistance in late pregnancy, indicating a potential role of SPARC in the pathophysiology of GDM.

  3. Effect of 8 weeks sprint interval training on serum levels of Adiponectin and insulin in overweight children

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    Abdolreza Kazemi

    2016-04-01

    Full Text Available Background: Scientific studies demonstrated that decreased blood Adiponectin level is associated with insulin resistance in obesity. Also it is well documented that exercise training exerts beneficial effects on obesity but there is few study regarding beneficial effects of sprint Interval training (SIT on childhood obesity. This study was intended to investigate the effect of SIT on serum levels of Adiponectin and insulin in overweight children. Material and Methods: In this study thirty-two obese boy (BMI=27 were randomly assigned to sprint Interval Training (SIT (N=16 and control group(C (N=16. Training protocol consisted of 30s and 90s all-out running that performed 3 sessions per week for 8 weeks. Blood samples were measured by ELISA analysis. Data were analyzed using Independent sample t-test. Results: 8 weeks SIT increase serum levels of Adiponectin (P=0.028 and decrease insulin level (P=0.00. This change was directly related to decrease in values of BMI (P=0.01, total cholesterol (P=0.00 and body weight (P=0.02, but significant change in serum levels of HDL (P=0.50, LDL (P=0.17 and TG (P=0.60 wasn’t observed. Conclusion: These findings suggest that SIT may ameliorate the metabolic abnormalities associated with obesity in children probably through elevation of serum Adiponectin level.

  4. Insulin secretion in lipodystrophic HIV-infected patients is associated with high levels of nonglucose secretagogues and insulin resistance of beta-cells

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Storgaard, Heidi

    2004-01-01

    lipodystrophy (controls). Thirty minutes before start of the clamp, a bolus of glucose was injected intravenously to stimulate endogenous insulin secretion. Insulin sensitivity index (SiRd) was estimated from glucose tracer analysis. LIPO displayed increased basal ISR (69%), clamp ISR (114%), basal insulin (130......, and glucose (all r > 0.41, P triglyceride, and glucagon (all r > 0.51, P triglyceride (r = 0.45, P ...%), and clamp insulin (32%), all P 0.65, P glucose. In control subjects, ISR(basal) correlated significantly with insulin, glucagon...

  5. Central insulin administration improves odor-cued reactivation of spatial memory in young men.

    Science.gov (United States)

    Brünner, Yvonne F; Kofoet, Anja; Benedict, Christian; Freiherr, Jessica

    2015-01-01

    Insulin receptors are ubiquitously found in the human brain, comprising the olfactory bulb, essential for odor processing, and the hippocampus, important for spatial memory processing. The present study aimed at examining if intranasal insulin, which is known to transiently increase brain insulin levels in humans, would improve odor-cued reactivation of spatial memory in young men. We applied a double-blind, placebo-controlled, counterbalanced within-subject design. The study was conducted at the research unit of a university hospital. Interventions/Participants/Main Outcome Measures: Following intranasal administration of either insulin (40 I.U.) or placebo, male subjects (n = 18) were exposed to eight odors. During each odor exposure, a green-colored field was presented on a 17-in. computer screen. During immediate recall (comprising 3 runs), the participants were re-exposed to each odor cue, and were asked to select the corresponding field (with visual feedback after each response). The delayed recall was scheduled ∼10 min later (without feedback). To test if insulin's putative effect on odor-place memory would be domain-specific, participants also performed a separate place and odor recognition task. Intranasal insulin improved the delayed but not immediate odor-cued recall of spatial memory. This effect was independent of odor type and in the absence of systemic side effects (eg, fasting plasma glucose levels remained unaltered). Place and odor recognition were unaffected by the insulin treatment. These findings suggest that acute intranasal insulin improves odor-cued reactivation of spatial memory in young men.

  6. Correlation analysis of sex hormone level and insulin resistance in patients with polycystic ovarian syndrome

    International Nuclear Information System (INIS)

    Yuan Xiongzhou; Yuan Guofu; Zhang Xinying; Li Xiufen; Lv Huihui; Sun Zhiru

    2012-01-01

    Objective: To explore the etiology and mechanisms of polycystic ovarian syndrome (PCOS). Methods: The levels of serum LH, FSH, E 2 , P and T in patients with PCOS were detected by ECLIA. The insulin release test was detected by RIA and the glucose tolerance test by enzymatic method. Results: It showed that 28.2% patients only insulin resistance (IR), 13.1% patients also existed of IR and glucose tolerance damage, 5.5% patients only had glucose tolerance damage. Pure IR in the obese accounted for 35.7%; Pure impaired glucose tolerance, fat person accounted for 36.3%; IR with impaired glucose tolerance, fat person accounted for 34.6%. There were no significant differences on LH, LH/FSH, E 2 , T levels between the obese group and the non-obese group (P> 0.05), but there was a significant difference on fasting blood glucose and fasting insulin levels between them (P<0.05). The menstrual cycle and follicular number between the obese group and the non-obese group had significantly differences (P<0.05). Conclusion: There exist different degrees of IR and glucose tolerance damage in most of PCOS patients. The obese people account for higher proportion in patients with IR and glucose tolerance. The obesity can promote the formation of IR and increase reproductive dysfunction. (authors)

  7. Clinical significance of changes of serum true insulin and proinsulin levels in relations of patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Tian Xiaoping; Huang Huijian; Huang Haibo; Wu Yan; He Haoming

    2004-01-01

    Objective: To explore the degree of insulin resistance and β-cell secretory function impairment in close (1st degree) relations of patients with type 2 diabetes (DMII). Methods: Serum true insulin (TI), pro-insulin (PI), immunoreactive insulin (IRI) levels at fasting and after oral 75g glucose loading were determined in: 1) patients with DM 2, n=65 2)relations of DM 2 patients with impaired glucose tolerance (IGT), n=34 3) relations of DM 2 patients with normal glucose tolerance (NGT), n=66 and 4) controls, n=48. HOMA-IR and HOMA-β cell secretory indices were calculated from the data. Results: Fasting serum PI levels were significantly higher in DM 2 patients, relations with IGT and NGT than those in the controls (t=2.38, t=2.16, t=1.95, P 1 C percentages were significantly higher in DM 2 patients and IGT, NGT groups than those in controls (t=3.67, t=2.45, t=1.97, P 1 C percentage, fasting TI and IRI levels. Conclusion: Insulin resistance was already obvious in those relations of DM 2 patients with normal glucose tolerance and β-cell secretory function impairment was also present. Early intervention in these subjects might be beneficial. (authors)

  8. Anti-diabetic activity of insulin-degrading enzyme inhibitors mediated by multiple hormones.

    Science.gov (United States)

    Maianti, Juan Pablo; McFedries, Amanda; Foda, Zachariah H; Kleiner, Ralph E; Du, Xiu Quan; Leissring, Malcolm A; Tang, Wei-Jen; Charron, Maureen J; Seeliger, Markus A; Saghatelian, Alan; Liu, David R

    2014-07-03

    Despite decades of speculation that inhibiting endogenous insulin degradation might treat type-2 diabetes, and the identification of IDE (insulin-degrading enzyme) as a diabetes susceptibility gene, the relationship between the activity of the zinc metalloprotein IDE and glucose homeostasis remains unclear. Although Ide(-/-) mice have elevated insulin levels, they exhibit impaired, rather than improved, glucose tolerance that may arise from compensatory insulin signalling dysfunction. IDE inhibitors that are active in vivo are therefore needed to elucidate IDE's physiological roles and to determine its potential to serve as a target for the treatment of diabetes. Here we report the discovery of a physiologically active IDE inhibitor identified from a DNA-templated macrocycle library. An X-ray structure of the macrocycle bound to IDE reveals that it engages a binding pocket away from the catalytic site, which explains its remarkable selectivity. Treatment of lean and obese mice with this inhibitor shows that IDE regulates the abundance and signalling of glucagon and amylin, in addition to that of insulin. Under physiological conditions that augment insulin and amylin levels, such as oral glucose administration, acute IDE inhibition leads to substantially improved glucose tolerance and slower gastric emptying. These findings demonstrate the feasibility of modulating IDE activity as a new therapeutic strategy to treat type-2 diabetes and expand our understanding of the roles of IDE in glucose and hormone regulation.

  9. Ethanolic Extract of Butea monosperma Leaves Elevate Blood Insulin Level in Type 2 Diabetic Rats, Stimulate Insulin Secretion in Isolated Rat Islets, and Enhance Hepatic Glycogen Formation

    Directory of Open Access Journals (Sweden)

    Mehdi Bin Samad

    2014-01-01

    Full Text Available We measured a vast range of parameters, in an attempt to further elucidate previously claimed antihyperglycemic activity of Butea monosperma. Our study clearly negates the possibility of antidiabetic activity by inhibited gastrointestinal enzyme action or by reduced glucose absorption. Reduction of fasting and postprandial glucose level was reconfirmed (P<0.05. Improved serum lipid profile via reduced low density lipoprotein (LDL, cholesterol, triglycerides (TG, and increased high density lipoprotein (HDL was also reestablished (P<0.05. Significant insulin secretagogue activity of B. monosperma was found in serum insulin assay of B. monosperma treated type 2 diabetic rats (P<0.01. This was further ascertained by our study on insulin secretion on isolated rat islets (P<0.05. Improved sensitivity of glucose was shown by the significant increase in hepatic glycogen deposition (P<0.05. Hence, we concluded that antihyperglycemic activity of B. monosperma was mediated by enhanced insulin secretion and enhanced glycogen formation in the liver.

  10. Defects in TLR3 expression and RNase L activation lead to decreased MnSOD expression and insulin resistance in muscle cells of obese people

    DEFF Research Database (Denmark)

    Fabre, Odile Martine Julie; Breuker, C; Amouzou, C

    2014-01-01

    Obesity is associated with chronic low-grade inflammation and oxidative stress that blunt insulin response in its target tissues, leading to insulin resistance (IR). IR is a characteristic feature of type 2 diabetes. Skeletal muscle is responsible for 75% of total insulin-dependent glucose uptake...... with palmitate, a saturated free fatty acid (FFA) known to induce inflammation and oxidative stress via TLR4 activation. While RNase L and RLI levels remained unchanged, OAS level was decreased in primary myotubes from insulin-resistant obese subjects (OB-IR) compared with myotubes from insulin-sensitive obese......; consequently, skeletal muscle IR is considered to be the primary defect of systemic IR development. Interestingly, some obese people stay insulin-sensitive and metabolically healthy. With the aim of understanding this difference and identifying the mechanisms responsible for insulin sensitivity maintenance...

  11. Calcineurin inhibitors acutely improve insulin sensitivity without affecting insulin secretion in healthy human volunteers

    DEFF Research Database (Denmark)

    Øzbay, Aygen; Møller, Niels; Juhl, Claus

    2012-01-01

    and tacrolimus has been attributed to both beta cell dysfunction and impaired insulin sensitivity. WHAT THIS STUDY ADDS: This is the first trial to investigate beta cell function and insulin sensitivity using gold standard methodology in healthy human volunteers treated with clinically relevant doses...... of ciclosporin and tacrolimus. We document that both drugs acutely increase insulin sensitivity, while first phase and pulsatile insulin secretion remain unaffected. This study demonstrates that ciclosporin and tacrolimus have similar acute effects on glucose metabolism in healthy humans. AIM The introduction...... of calcineurin inhibitors (CNIs) ciclosporin (CsA) and tacrolimus (Tac) has improved the outcome of organ transplants, but complications such as new onset diabetes mellitus after transplantation (NODAT) cause impairment of survival rates. The relative contribution of each CNI to the pathogenesis and development...

  12. Omentin, an adipokine with insulin-sensitizing properties, is negatively associated with insulin resistance in normal gestation.

    Science.gov (United States)

    Brandt, Benny; Mazaki-Tovi, Shali; Hemi, Rina; Yinon, Yoav; Schiff, Eyal; Mashiach, Roy; Kanety, Hannah; Sivan, Eyal

    2015-05-01

    Omentin, a newly identified adipokine, enhances insulin mediated glucose uptake in human adipocytes, thus, inducing systemic insulin-sensitizing effect. The aims of this study were to determine whether circulating maternal omentin levels are associated with insulin resistance indices and to assess which compartment, maternal, fetal, or placental, is the source of omentin in maternal circulation. Fasting serum glucose, insulin, and omentin were determined in 25 healthy pregnant women at the third trimester, before and 3 days after elective cesarean section. Cord blood omentin was measured in the 25 term neonates. Homeostasis model assessment (HOMA) was used to evaluate insulin sensitivity before and after delivery. Antepartum maternal omentin levels were negatively correlated with insulin levels (r=-0.41, P=0.04) and positively correlated with insulin sensitivity (HOMA%S; r=0.4, P=0.04). Postpartum omentin levels were negatively correlated with maternal body mass index (r=-0.44, P=0.02). Median maternal omentin levels was comparable before and after delivery (57.2, inter-quartile range: 38.2-76.2 ng/mL vs. 53.4, 39.8-69.4 ng/mL, respectively, P=0.25) and highly correlated (r=0.83, Pinsulin resistance indices, suggesting that this adipokine may play a role in metabolic adaptations of normal gestation. The strong correlation between anteparum and postpartum maternal omentin levels, as well as the lack of association between maternal and neonatal omentin levels, suggest that placental or fetal compartments are unlikely as the main source of circulating maternal omentin.

  13. Insulin structure and stability.

    Science.gov (United States)

    Brange, J; Langkjoer, L

    1993-01-01

    Insulin is composed of 51 amino acids in two peptide chains (A and B) linked by two disulfide bonds. The three-dimensional structure of the insulin molecule (insulin monomer), essentially the same in solution and in solid phase, exists in two main conformations. These differ in the extent of helix in the B chain which is governed by the presence of phenol or its derivatives. In acid and neutral solutions, in concentrations relevant for pharmaceutical formulation, the insulin monomer assembles to dimers and at neutral pH, in the presence of zinc ions, further to hexamers. Many crystalline modifications of insulin have been identified but only those with the hexamer as the basic unit are utilized in preparations for therapy. The insulin hexamer forms a relatively stable unit but some flexibility remains within the individual molecules. The intrinsic flexibility at the ends of the B chain plays an important role in governing the physical and chemical stability of insulin. A variety of chemical changes of the primary structure (yielding insulin derivatives), and physical modifications of the secondary to quaternary structures (resulting in "denaturation," aggregation, and precipitation) are known to affect insulin and insulin preparations during storage and use (Fig. 8). The tendency of insulin to undergo structural transformation resulting in aggregation and formation of insoluble insulin fibrils has been one of the most intriguing and widely studied phenomena in relation to insulin stability. Although the exact mechanism of fibril formation is still obscure, it is now clear that the initial step is an exposure of certain hydrophobic residues, normally buried in the three-dimensional structure, to the surface of the insulin monomer. This requires displacement of the COOH-terminal B-chain residues from their normal position which can only be accomplished via monomerization of the insulin. Therefore, most methods stabilizing insulin against fibrillation share the

  14. Vitamin A and feeding statuses modulate the insulin-regulated gene expression in Zucker lean and fatty primary rat hepatocytes.

    Directory of Open Access Journals (Sweden)

    Wei Chen

    Full Text Available Unattended hepatic insulin resistance predisposes individuals to dyslipidemia, type 2 diabetes and many other metabolic complications. The mechanism of hepatic insulin resistance at the gene expression level remains unrevealed. To examine the effects of vitamin A (VA, total energy intake and feeding conditions on the insulin-regulated gene expression in primary hepatocytes of Zucker lean (ZL and fatty (ZF rats, we analyze the expression levels of hepatic model genes in response to the treatments of insulin and retinoic acid (RA. We report that the insulin- and RA-regulated glucokinase, sterol regulatory element-binding protein-1c and cytosolic form of phosphoenolpyruvate carboxykinase expressions are impaired in hepatocytes of ZF rats fed chow or a VA sufficient (VAS diet ad libitum. The impairments are partially corrected when ZF rats are fed a VA deficient (VAD diet ad libitum or pair-fed a VAS diet to the intake of their VAD counterparts in non-fasting conditions. Interestingly in the pair-fed ZL and ZF rats, transient overeating on the last day of pair-feeding regimen changes the expression levels of some VA catabolic genes, and impairs the insulin- and RA-regulated gene expression in hepatocytes. These results demonstrate that VA and feeding statuses modulate the hepatic insulin sensitivity at the gene expression level.

  15. Application of insulin-like growth factor-I and insulin release test in diabetes mellitus

    International Nuclear Information System (INIS)

    Chen Dong; Ma Yongxiu; Duan Wenruo

    2003-01-01

    The purpose of this study was to determine the role of insulin-like growth factor-I (IGF-I) and insulin release test (IRT) in understanding the extent of damage to ability of reducing blood sugar in different types of diabetes mellitus (DM) and in selection of treatment plan and adjustment of using drugs. OGTT, IRT and determination of IGF-I level of 67 normal subjects and 217 DM patients were performed. The result was analyzed comparatively. The level of IGF-I was negatively correlated with the level of fasting blood sugar, and positively correlated with the level of fasting insulin. Our conclusions are: There are two ways of reducing blood sugar: one is by insulin, and the other is by IGF-I. IRT can reflect the former better, and IGF-I the latter. The combination of these two is of significant value in diagnosis and treatment of DM

  16. High Insulin Levels in KK-Ay Diabetic Mice Cause Increased Cortical Bone Mass and Impaired Trabecular Micro-Structure

    Directory of Open Access Journals (Sweden)

    Cen Fu

    2015-04-01

    Full Text Available Type 2 diabetes mellitus (T2DM is a chronic disease characterized by hyperglycemia, hyperinsulinemia and complications, including obesity and osteoporosis. Rodents have been widely used to model human T2DM and investigate its effect on the skeleton. We aimed to investigate skeletal alterations in Yellow Kuo Kondo (KK-Ay diabetic mice displaying high insulin and glucose levels. Bone mineral density (BMD, micro-architecture and bone metabolism-related genes were analyzed. The total femoral areal BMD (aBMD, cortical volumetric BMD (vBMD and thickness were significantly increased in KK-Ay mice, while the trabecular vBMD and mineralized bone volume/tissue volume (BV/TV, trabecular thickness and number were decreased compared to C57BL mice. The expression of both osteoblast-related genes, such as osteocalcin (OC, bone sialoprotein, Type I Collagen, osteonectin, RUNX2 and OSX, and osteoclast-related genes, such as TRAP and TCIRG, were up-regulated in KK-Ay mice. Correlation analyses showed that serum insulin levels were positively associated with aBMD, cortical vBMD and thickness and negatively associated with trabecular vBMD and micro-architecture. In addition, serum insulin levels were positively related to osteoblast-related and osteoclast-related gene expression. Our data suggest that high insulin levels in KK-Ay diabetic mice may increase cortical bone mass and impair trabecular micro-structure by up-regulating osteoblast-and osteoclast-related gene expression.

  17. Circulating omentin-1 levels and its association with insulin resistance in newly diagnosed impaired glucose tolerant subjects

    Directory of Open Access Journals (Sweden)

    L Hossain

    2016-01-01

    Full Text Available Adipose tissue derived a novel adipokine; omentin -1, w hich has recently been characterized as a potent insulin-sensitizing agent, but its pathophysiologic role in the development of insulin resistance among the impaired glucose tolerance (IGT su bjects remains largely unknow n. The present study has been undertaken to explore the relationship of serum omentin -1 w ith insulin resistance in new ly diagnosed IGT subjects of Bangladeshi population. Fifty-five subjects w ith IGT and 50 (age, sex and body m ass index (BMI matched healthy control subjects w ere recruited in this study. Serum insulin and omentin-1 w ere measured by the ELISA technique. Insulin resistance (IR w as calculated by homeostasis model assessment (HOMA. HOMA-IR w as significantly higher (p < 0.001 as w ell as log transformed omentin-1 w as significantly low er (p = 0.031 in IGT subjects compared to the control. Pearson′s correlation analysis show ed a significant negative correlation of log omentin -1 w ith HOMA-IR (r = -0.290, p = 0.008 in all subjects. Multiple linear regression analysis show ed a significant negative association of HOMA-IR w ith log omentin-1 (β = -0.285, p = 0.017 in IGT subjects after adjusting the effects of potential confounders of glycated hemoglobin (HbA1c and triglyceride (TG. Binary logistic regression analysis show ed that log omentin-1 [odds ratio (OR = 0.631, p = 0.038] and HOMA-IR (OR = 1.998, p = 0.029 w ere found to be significant determinants of IGT after adjusting the effect of HbA1c and TG. Serum concentration of omentin-1 is decreased in the state of insulin resistance of IGT subjects and this reduction seemed to be mediated by adiposity and hyperglycemia among these subjects.

  18. Insulin resistance in porphyria cutanea tarda.

    Science.gov (United States)

    Calcinaro, F; Basta, G; Lisi, P; Cruciani, C; Pietropaolo, M; Santeusanio, F; Falorni, A; Calafiore, R

    1989-06-01

    It has been reported that patients with porphyria cutanea tarda (PCT) develop carbohydrate (CHO) intolerance and manifest diabetes melitus (DM) more frequently than the normal population. In order to verify whether this is due to insulin resistance we studied 5 patients with PCT and 5 normal subjects matched for age, sex and weight. In all the patients an evaluation consisted of the glycemic curve and insulin response to an iv glucose tolerance test (IVGTT: 0.33 g/kg) as well as of an evaluation of the circulating monocyte insulin receptors. Blood samples were drawn in the basal state to measure plasma levels of NEFA, glycerol, and intermediate metabolites. The patients with PCT showed normal glucose tolerance which was obtained, however, at the expense of the elevated insulin levels: therefore a condition of insulin resistance was demonstrated in these subjects. An involvement of the lipid metabolism, observed by the raised levels of plasma NEFA and glycerol, was also evident. The insulin binding to circulating monocytes was reduced but not enough to justify the degree of insulin resistance observed. Therefore, it could be hypothesized, in agreement with similar studies, that a postreceptor defect is responsible for the insulin-resistance observed in patients with PCT and that the reduction of insulin receptors is determined by the down regulation in response to elevated insulinemic levels. An alteration of the porphyrin metabolism might be responsible for this disorder.

  19. Monomeric insulins and their experimental and clinical implications.

    Science.gov (United States)

    Brange, J; Owens, D R; Kang, S; Vølund, A

    1990-09-01

    Due to the inherent pharmacokinetic properties of available insulins, normoglycemia is rarely, if ever, achieved in insulin-dependent diabetic patients without compromising their quality of life. Subcutaneous insulin absorption is influenced by many factors, among which the associated state of insulin (hexameric) in pharmaceutical formulation may be of importance. This review describes the development of a series of human insulin analogues with reduced tendency to self-association that, because of more rapid absorption, are better suited to meal-related therapy. DNA technology has made it possible to prepare insulins that remain dimeric or even monomeric at high concentration by introducing one or a few amino acid substitutions into human insulin. These analogues were characterized and used for elucidating the mechanisms involved in subcutaneous absorption and were investigated in preliminary clinical studies. Their relative receptor binding and in vitro potency (free-fat cell assay), ranging from 0.05 to 600% relative to human insulin, were strongly correlated (r = 0.97). In vivo, most of the analogues exhibited approximately 100% activity, explainable by a dominating receptor-mediated clearance. This was confirmed by clamp studies in which correlation between receptor binding and clearance was observed. Thus, an analogue with reduced binding and clearance gives higher circulating concentrations, counterbalancing the reduced potency at the cellular level. Absorption studies in pigs revealed a strong inverse correlation (r = 0.96) between the rate of subcutaneous absorption and the mean association state of the insulin analogues. These studies also demonstrated that monomeric insulins were absorbed three times faster than human insulin. In healthy subjects, rates of disappearance from subcutis were two to three times faster for dimeric and monomeric analogues than for human insulin. Concomitantly, a more rapid rise in plasma insulin concentration and an earlier

  20. Myostatin induces insulin resistance via Casitas B-lineage lymphoma b (Cblb)-mediated degradation of insulin receptor substrate 1 (IRS1) protein in response to high calorie diet intake.

    Science.gov (United States)

    Bonala, Sabeera; Lokireddy, Sudarsanareddy; McFarlane, Craig; Patnam, Sreekanth; Sharma, Mridula; Kambadur, Ravi

    2014-03-14

    To date a plethora of evidence has clearly demonstrated that continued high calorie intake leads to insulin resistance and type-2 diabetes with or without obesity. However, the necessary signals that initiate insulin resistance during high calorie intake remain largely unknown. Our results here show that in response to a regimen of high fat or high glucose diets, Mstn levels were induced in muscle and liver of mice. High glucose- or fat-mediated induction of Mstn was controlled at the level of transcription, as highly conserved carbohydrate response and sterol-responsive (E-box) elements were present in the Mstn promoter and were revealed to be critical for ChREBP (carbohydrate-responsive element-binding protein) or SREBP1c (sterol regulatory element-binding protein 1c) regulation of Mstn expression. Further molecular analysis suggested that the increased Mstn levels (due to high glucose or fatty acid loading) resulted in increased expression of Cblb in a Smad3-dependent manner. Casitas B-lineage lymphoma b (Cblb) is an ubiquitin E3 ligase that has been shown to specifically degrade insulin receptor substrate 1 (IRS1) protein. Consistent with this, our results revealed that elevated Mstn levels specifically up-regulated Cblb, resulting in enhanced ubiquitin proteasome-mediated degradation of IRS1. In addition, over expression or knock down of Cblb had a major impact on IRS1 and pAkt levels in the presence or absence of insulin. Collectively, these observations strongly suggest that increased glucose levels and high fat diet, both, result in increased circulatory Mstn levels. The increased Mstn in turn is a potent inducer of insulin resistance by degrading IRS1 protein via the E3 ligase, Cblb, in a Smad3-dependent manner.

  1. Circulating MOTS-c levels are decreased in obese male children and adolescents and associated with insulin resistance.

    Science.gov (United States)

    Du, Caiqi; Zhang, Cai; Wu, Wei; Liang, Yan; Wang, Anru; Wu, Shimin; Zhao, Yue; Hou, Ling; Ning, Qin; Luo, Xiaoping

    2018-04-25

    A novel bioactive peptide, mitochondrial-derived peptide (MOTS-c), has recently attracted attention as a potential prevention or therapeutic option for obesity and type 2 diabetes mellitus (T2DM). MOTS-c profiles have not yet been reported in human obesity and T2DM. We aimed to determine circulating MOTS-c levels in obesity and explore the association between MOTS-c levels and various metabolic parameters. In this case-control study, 40 obese children and adolescents (27 males) and 57 controls (40 males) were recruited in the Hubei Province of China in 2017. Circulating MOTS-c levels were measured, clinical data (e.g., glucose, insulin and lipid profile) were recorded, and anthropometric measurements were performed. Finally, we investigated correlations between MOTS-c levels and related variables. MOTS-c levels were significantly decreased in the obese group compared with the control group (472.61 ± 22.83 ng/mL vs. 561.64 ± 19.19 ng/mL, p c levels were significantly decreased in obese male children and adolescents compared to their counterparts (465.26 ± 24.53 ng/mL vs. 584.07 ± 21.18 ng/mL, p 0.05). Further, MOTS-c levels were negatively correlated with body mass index (BMI), BMI standard deviation score, waist circumference, waist-to-hip ratio, fasting insulin level, HOMA-IR, and HbA1c in the male cohort. Circulating MOTS-c levels were decreased in obese male children and adolescents and correlated with markers of insulin resistance and obesity. This article is protected by copyright. All rights reserved.

  2. Effect of Carthamus tinctorius (Safflower) on fasting blood glucose and insulin levels in alloxan induced diabetic rabbits.

    Science.gov (United States)

    Qazi, Nasreen; Khan, Rafeeq Alam; Rizwani, Ghazala H; Feroz, Zeeshan

    2014-03-01

    Diabetes mellitus is a major threat to present and future generations. The role of herbal medication has emerged as a safe alternative to currently available medication due to its decreased potential to produce side effects, hence effect of Carthamus tinctorius was observed on fasting blood glucose and insulin levels in alloxan induced diabetic rabbits. Thirty five healthy male rabbits were divided into 5 groups with 7 rabbits in each (Normal control, diabetic control, diabetic treated with glibenclamide, diabetic treated with Carthamus tinctorius extract at doses of 200 and 300mg/kg of body weight). Drug and extract were given orally for 30 days and the values for blood glucose levels were observed after 15(th) and 30(th) day of treatment by using standard reagent kits provided by Human Germany. While insulin levels were checked at the end of the study by using Architect i1000 by Abbott Diagnostics USA. Animals were also observed for any gross toxicity during the study. Results revealed that Carthamus tinctorius has significant hypoglycemic effect at 200mg/kg and 300mg/kg doses as compared to diabetic control group. Insulin levels were significantly increased in Glibenclamide treated as well as Carthamus tinctorius treated groups as compared to diabetic control.

  3. Reduced Systemic Levels of IL-10 Are Associated with the Severity of Obstructive Sleep Apnea and Insulin Resistance in Morbidly Obese Humans

    Directory of Open Access Journals (Sweden)

    Sonia Leon-Cabrera

    2015-01-01

    Full Text Available Obstructive sleep apnea (OSA has been related to elevation of inflammatory cytokines and development of insulin resistance in morbidly obese (MO subjects. However, it is still unclear whether the systemic concentration of anti-inflammatory mediators is also affected in MO subjects directly related to the severity of OSA and level of insulin resistance. Normal weight and MO subjects were subjected to overnight polysomnography in order to establish the severity of OSA, according to the apnea-hypopnea index (AHI. Blood samples were obtained for estimation of total cholesterol and triglycerides, insulin, glucose, insulin resistance, tumor necrosis factor alpha (TNF-α, interleukin 12 (IL12, and interleukin 10 (IL-10. Serum levels of IL-10 were significantly lower in MO subjects with OSA than in MO and control individuals without OSA. Besides being inversely associated with serum TNF-α and IL-12, decreased IL-10 levels were significantly related to increased AHI, hyperinsulinemia, and insulin resistance. Serum IL-10 is significantly reduced in morbidly obese subjects with severe OSA while also showing a clear relationship with a state of hyperinsulinemia and insulin resistance probably regardless of obesity in the present sample. It may be of potential clinical interest to identify the stimulatory mechanisms of IL-10 in obese individuals with OSA.

  4. Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis.

    Science.gov (United States)

    Haberzettl, Petra; McCracken, James P; Bhatnagar, Aruni; Conklin, Daniel J

    2016-06-01

    Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1(+)/Sca-1(+) cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Copyright © 2016 the American Physiological Society.

  5. Higher glucose, insulin and insulin resistance (HOMA-IR) in childhood predict adverse cardiovascular risk in early adulthood: the Pune Children's Study.

    Science.gov (United States)

    Yajnik, Chittaranjan S; Katre, Prachi A; Joshi, Suyog M; Kumaran, Kalyanaraman; Bhat, Dattatray S; Lubree, Himangi G; Memane, Nilam; Kinare, Arun S; Pandit, Anand N; Bhave, Sheila A; Bavdekar, Ashish; Fall, Caroline H D

    2015-07-01

    The Pune Children's Study aimed to test whether glucose and insulin measurements in childhood predict cardiovascular risk factors in young adulthood. We followed up 357 participants (75% follow-up) at 21 years of age who had undergone detailed measurements at 8 years of age (glucose, insulin, HOMA-IR and other indices). Oral glucose tolerance, anthropometry, plasma lipids, BP, carotid intima-media thickness (IMT) and arterial pulse wave velocity (PWV) were measured at 21 years. Higher fasting glucose, insulin and HOMA-IR at 8 years predicted higher glucose, insulin, HOMA-IR, BP, lipids and IMT at 21 years. A 1 SD change in 8 year variables was associated with a 0.10-0.27 SD change at 21 years independently of obesity/adiposity at 8 years of age. A greater rise in glucose-insulin variables between 8 and 21 years was associated with higher cardiovascular risk factors, including PWV. Participants whose HOMA-IR measurement remained in the highest quartile (n = 31) had a more adverse cardiovascular risk profile compared with those whose HOMA-IR measurement remained in the lowest quartile (n = 28). Prepubertal glucose-insulin metabolism is associated with adult cardiovascular risk and markers of atherosclerosis. Our results support interventions to improve glucose-insulin metabolism in childhood to reduce cardiovascular risk in later life.

  6. Insulin-like growth factor 1, liver enzymes, and insulin resistance in patients with PCOS and hirsutism.

    Science.gov (United States)

    Çakir, Evrim; Topaloğlu, Oya; Çolak Bozkurt, Nujen; Karbek Bayraktar, Başak; Güngüneş, Aşkın; Sayki Arslan, Müyesser; Öztürk Ünsal, İlknur; Tutal, Esra; Uçan, Bekir; Delıbaşi, Tuncay

    2014-01-01

    Hyperinsulinemia and insulin resistance are commonly seen in patients with hirsutism and polycystic ovary syndrome (PCOS), and are associated with cardiovascular disease risk. However, it is not yet known whether insulin-like growth factor I (IGF-I) and alanine transaminase (ALT) produced by the liver play roles in hyperinsulinemia and subclinical atherosclerotic process in patients with PCOS and idiopathic hirsutism (IH). This was a prospective case-controlled study. The study population consisted of 25 reproductive-age PCOS women, 33 women with IH, and 25 control subjects. Mean IGF-I levels and median ALT levels were higher in patients with IH and PCOS than controls, but these differences were not statistically significant. The participants who had a homeostasis model assessment insulin resistance index (HOMA-IR) greater than 2.7 had significantly higher IGF-1 and ALT levels. ALT levels were positively correlated with body mass index, FG, insulin and HOMA-IR. The study illustrated that IGF-1 and ALT levels were significantly higher in patients with increased insulin resistance. Due to short disease duration in younger participants, we did not observe any correlation between IGF-1 and hyperinsulinemia. These findings suggest that increased hepatic production of IGF-I and ALT might be an early indicator of insulin resistance in hirsutism.

  7. Insulin aspart pharmacokinetics

    DEFF Research Database (Denmark)

    Rasmussen, Christian Hove; Roge, Rikke Meldgaard; Ma, Zhulin

    2014-01-01

    Background: Insulin aspart (IAsp) is used by many diabetics as a meal-time insulin to control postprandial glucose levels. As is the case with many other insulin types, the pharmacokinetics (PK), and consequently the pharmacodynamics (PD), is associated with clinical variability, both between...... to investigate and quantify the properties of the subcutaneous depot. Data from Brange et al. (1990) are used to determine the effects of insulin chemistry in subcutis on the absorption rate. Intravenous (i.v.) bolus and infusion PK data for human insulin are used to understand and quantify the systemic...... distribution and elimination (Porksen et al., 1997; Sjostrand et al., 2002). PK and PD profiles for type 1 diabetics from Chen et al. (2005) are analyzed to demonstrate the effects of IAsp antibodies in terms of bound and unbound insulin. PK profiles from Thorisdottir et al. (2009) and Ma et al. (2012b...

  8. Insulin elevates leptin secretion and mRNA levels via cyclic AMP in 3T3-L1 adipocytes deprived of glucose

    Directory of Open Access Journals (Sweden)

    Tomomi Tsubai

    2016-11-01

    Conclusion: Insulin alone stimulates leptin secretion and elevates leptin mRNA levels via cAMP under the lack of glucose metabolism, while glucose is a significant and ambivalent effector on the insulin effects of leptin.

  9. The Emerging Role of Branched-Chain Amino Acids in Insulin Resistance and Metabolism

    Directory of Open Access Journals (Sweden)

    Mee-Sup Yoon

    2016-07-01

    Full Text Available Insulin is required for maintenance of glucose homeostasis. Despite the importance of insulin sensitivity to metabolic health, the mechanisms that induce insulin resistance remain unclear. Branched-chain amino acids (BCAAs belong to the essential amino acids, which are both direct and indirect nutrient signals. Even though BCAAs have been reported to improve metabolic health, an increased BCAA plasma level is associated with a high risk of metabolic disorder and future insulin resistance, or type 2 diabetes mellitus (T2DM. The activation of mammalian target of rapamycin complex 1 (mTORC1 by BCAAs has been suggested to cause insulin resistance. In addition, defective BCAA oxidative metabolism might occur in obesity, leading to a further accumulation of BCAAs and toxic intermediates. This review provides the current understanding of the mechanism of BCAA-induced mTORC1 activation, as well as the effect of mTOR activation on metabolic health in terms of insulin sensitivity. Furthermore, the effects of impaired BCAA metabolism will be discussed in detail.

  10. Higher intramuscular triacylglycerol in women does not impair insulin sensitivity and proximal insulin signaling

    DEFF Research Database (Denmark)

    Høeg, Louise; Roepstorff, Carsten; Thiele, Maja

    2009-01-01

    that despite 47% higher IMTG levels in women in the follicular phase whole body as well as leg insulin sensitivity are higher than in matched men. This was not explained by sex differences in proximal insulin signalling in women. In women it seems that a high capillary density and type 1 muscle fiber...... expression may be important for insulin action. Key words: Muscle Triglycerides, gender, insulin action, sex paradox....

  11. Status of serum adiponectin related to insulin resistance in prediabetics

    International Nuclear Information System (INIS)

    Ahsan, S.; Ahmed, S.D.H.; Nauman, K

    2014-01-01

    Obejctive: To find the status of serum adiponectin in individuals progressing towards Type 2 diabetes mellitus and compare it with normal glucose tolerant subjects to determine the stage where alteration of adiponectin occurred. Methods: The cross-sectional study was carried out at the Department of Biochemistry, Jinnah Postgraduate Medical Centre, Karachi, during January to August 2008. Subjects were invited through various diabetes screening camps. A total of 608 subjects >30 years of age without prior history of diabetes were screened through fasting plasma glucose and 2-hour oral glucose tolerance test. Forty randomly selected pre-diabetic subjects and 40 age and gender-matched subjects were included in the study. Anthropometric measurements were done. Serum insulin and adiponectin were estimated by enzyme-linked immunosorbent assay. Homeostasis model assessment of insulin resistance (HOMA-IR) was used to calculate insulin resistance mathematically. Result: Mean fasting and two-hour plasma glucose, body mass index, waist, hip circumference and blood pressure were significantly raised in pre-diabetics compared to those with normal glucose tolerance. Adiponectin was significantly decreased, while insulin and HOMA-IR were raised significantly in the pre-diabetics. Adiponectin showed significant negative correlation with body mass index (r=-0.31, p=0.005), fasting plasma glucose (r=-0.24, p= 0.032), 2-hour plasma glucose (r=-0.42, p<0.0001)), insulin (r-0.43, p<0.0001) and HOMA-IR (r= -0.43, p<0.0001) and remained significant after adjustment of body mass index, gender and insulin level in pre-diabetics. Conclusion: Adiponectin estimation may help in earlier identification of impending diabetes. However, casual link between adiponectin and pre-diabetes remained unexplored due to the study design and small sample size that warrants longitudinal large-scale studies. (author)

  12. Nasal insulin changes peripheral insulin sensitivity simultaneously with altered activity in homeostatic and reward-related human brain regions.

    Science.gov (United States)

    Heni, M; Kullmann, S; Ketterer, C; Guthoff, M; Linder, K; Wagner, R; Stingl, K T; Veit, R; Staiger, H; Häring, H-U; Preissl, H; Fritsche, A

    2012-06-01

    Impaired insulin sensitivity is a major factor leading to type 2 diabetes. Animal studies suggest that the brain is involved in the regulation of insulin sensitivity. We investigated whether insulin action in the human brain regulates peripheral insulin sensitivity and examined which brain areas are involved. Insulin and placebo were given intranasally. Plasma glucose, insulin and C-peptide were measured in 103 participants at 0, 30 and 60 min. A subgroup (n = 12) was also studied with functional MRI, and blood sampling at 0, 30 and 120 min. For each time-point, the HOMA of insulin resistance (HOMA-IR) was calculated as an inverse estimate of peripheral insulin sensitivity. Plasma insulin increased and subsequently decreased. This excursion was accompanied by slightly decreased plasma glucose, resulting in an initially increased HOMA-IR. At 1 h after insulin spray, the HOMA-IR subsequently decreased and remained lower up to 120 min. An increase in hypothalamic activity was observed, which correlated with the increased HOMA-IR at 30 min post-spray. Activity in the putamen, right insula and orbitofrontal cortex correlated with the decreased HOMA-IR at 120 min post-spray. Central insulin action in specific brain areas, including the hypothalamus, may time-dependently regulate peripheral insulin sensitivity. This introduces a potential novel mechanism for the regulation of peripheral insulin sensitivity and underlines the importance of cerebral insulin action for the whole organism.

  13. Study on the changes of serum adiponectin (APN), insulin, C-reactive protein (CRP) and leptin levels after one year treatment in patients with type 2 diabetes

    International Nuclear Information System (INIS)

    Du Tongxin; Wang Zizheng; Wang Shukui; Li Yan; Fu Lei; Lin Yanli; Qu Wei; Qi Shaokang; Tao Xiaojun

    2005-01-01

    Objective: To investigate the β-cell function status and possible mechanism of insulin resistance in patients with type 2 diabetes through studies on the changes of serum APN, insulin, CRP, leptin, insulin antibody and glutamic acid decarboxylase antibody (GAD-Ab) levels after one year of treatment. Methods: Serum levels of the above four parameters and the positive rate of the two antibodies were measured (with CLIA, ELISA and RIA as appropriately) in 184 patients with type 2 diabetes and 30 controls as well as in 75 patients after one year of treatment. Results: The serum contents of insulin, leptin, CRP, insulin antibody in patients with type 2 diabetes were significantly higher (P<0.01) and APN levels significantly lower (P<0.001) than those in controls. Levels of APN were negatively correlated with those of the other parameters. In the 75 treated patients, levels of those parameters (with the exception of APN and insulin-antibody) decreased significantly. However, the APN levels were significantly increased (vs before treatment, P<0.001). Conclusion: Further study on the dynamic changes of these parameters in the diabetic patients might elucidate certain key-points in the pathogenesis of the disease. (authors)

  14. Lack of effect of a moderate hypocaloric diet on visfatin levels in morbid obese patients: relationship with insulin resistance.

    Science.gov (United States)

    De Luis, D A; Gonzalez Sagrado, M; Conde, R; Aller, R; Izaola, O; Castro, M J; Romero, E

    2010-12-01

    The insulin-mimetic adipocytokine visfatin has been related to obesity. The aim of this study was to examine whether weight loss could change visfatin concentrations in morbidly obese patients and its relationship with insulin resistance. This was an interventional study analyzing a population of 41 morbidly obese patients. A biochemical analysis was realized before and after 2 months on a hypocaloric diet. After weight loss (average 4.41%), BMI, weight, fat mass, fat free mass, waist circumference, systolic blood pressure, serum glucose, total cholesterol, insulin and HOMA decreased. The serum concentrations of visfatin did not decrease (43.5 + 30.8 vs. 47.1 + 38.1 ng/ml). In the multivariate analysis visfatin concentrations as a dependent variable, only C reactive protein remained as an independent predictor in the model before diet, with an increase of 1.82 ng/ml (CI 95%: 0.02 - 3.61) basal visfatin concentrations with each increase of 1 mg/dl of CRP. Only HOMA remained as an independent predictor in the model after diet, with an increase of 11.4 ng/ml (CI 95%: 1.76 - 21.11) posttreatment visfatin concentrations with each increase of 1 unit HOMA. Weight reduction after a 2 months on a hypocaloric diet is not associated with a significant change in circulating visfatin in morbidly obese patients.

  15. Insulin Resistance and Prediabetes

    Science.gov (United States)

    ... Your Baby is Born Monogenic Diabetes Insulin Resistance & Prediabetes Insulin resistance and prediabetes occur when your body ... will stay in the healthy range. What is prediabetes? Prediabetes means your blood glucose levels are higher ...

  16. Variations in insulin responsiveness in rat fat cells are due to metabolic differences rather than insulin binding

    DEFF Research Database (Denmark)

    Hansen, Finn Mølgård; Nilsson, Poul; Sonne, Ole

    1983-01-01

    -insulin to fat cells. Insulin binding was not correlated to the plasma insulin level which however was reflected in the lipoprotein lipase activity in the adipose tissue. In conclusion, these results indicate that variations in insulin responsiveness in fat cells are due to alterations in cellular metabolism...

  17. UK service level audit of insulin pump therapy in paediatrics.

    Science.gov (United States)

    Ghatak, A; Paul, P; Hawcutt, D B; White, H D; Furlong, N J; Saunders, S; Morrison, G; Langridge, P; Weston, P J

    2015-12-01

    To conduct an audit of insulin pump therapy in the UK after the issue of guidelines for the use of continuous subcutaneous insulin infusion by NICE in 2008 (Technology Appraisal 151). All centres in the UK, providing pump services to children and young people were invited to participate in an online audit. Audit metrics were aligned to NICE Technology Appraisal 151 and an electronic data collection tool was used. Of the 176 UK centres identified as providing pump services, 166 (94.3%) participated in the study. A total of 5094 children and young people were identified as using continuous subcutaneous insulin infusion (19% of all paediatric patients with Type 1 diabetes), with a median (range) of 16.9 (0.67-69.4)% per centre. Units had a median of 0.58 consultant sessions, 0.43 full-time equivalent diabetic specialist nurses, and 0.1 full-time equivalent dieticians delivering the pump service. The majority of this time was not formally funded. Families could access 24-h clinical and technical support (83% units), although the delivery varied between consultant, diabetic specialist nurse and company representatives. Only 53% of units ran, or accessed, structured education programmes for continuous subcutaneous insulin infusion use. Most units (86%) allowed continuous subcutaneous insulin infusion use for paediatric inpatients, but only 56% had written guidelines for this scenario. Nine percent of units had encountered funding refusal for a patient fulfilling NICE (Technology Appraisal 151) criteria. The number of children and young people on continuous subcutaneous insulin infusion therapy is consistent with numbers estimated by NICE. There is a worrying lack of funded healthcare professional time. The audit also identified gaps in the provision of structured education and absence of written inpatient guidelines. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

  18. Study on the relationship between changes of serum, adiponectin some inflammatory cytokines levels and insulin resistance in newly diagnosed type 2 diabetes mellitus patients

    International Nuclear Information System (INIS)

    Feng Kun; Wng Dan; Duan Binhong; Yang Yuzhi

    2009-01-01

    Objective: To study the relationship between changes of serum adiponectin,interleukin-6 (IL-6)tumor necrosis factor-α (TNF-α) levels and insulin resistance (IR), obesity parameters in newly diagnosed type 2 diabetes mellitus (DM2) patients. Methods: Serum adiponectin (with RIA), IL-6, TNF-α (with ELISA) levels as well as fBG, 2hPG, fasting insulin, 2h insulin, lipid profile were measured in 42 obese newly diagnosed DM2 patients (BMI>25), 50 non-obese DM2 patients (BMI<25) and 40 controls. Results: The levels of adiponectin obese group were significantly those in the other groups (P<0.05 and P<0.01), while levels in non-obese group were significantly lower than those in controls (P<0.01). The levels of IL-6 and TNF-α in obese group were significantly higher than those in the other groups (P<0.05 and P<0.01), while the levels in non-obese group were significantly higher than the levels in controls (P<0.01). The adiponectin levels were negatively correlated with insulin resistance(HOMA-IR) and BMI, while the cytokines levels were posisitively correlated with HOMA-IR and BMI. Conclusion: Adiponectin, IL-6 and TNF-α are closely related with insulin resistance, and take parts in development of the abnormal glucose metabolism. (authors)

  19. The fluctuation of blood glucose, insulin and glucagon concentrations before and after insulin therapy in type 1 diabetes

    Science.gov (United States)

    Arif, Idam; Nasir, Zulfa

    2015-09-01

    A dynamical-systems model of plasma glucose, insulin and glucagon concentrations has been developed to investigate the effects of insulin therapy on blood glucose, insulin and glucagon regulations in type 1 diabetic patients. Simulation results show that the normal regulation of blood glucose concentration depends on insulin and glucagon concentrations. On type 1 diabetic case, the role of insulin on regulating blood glucose is not optimal because of the destruction of β cells in pancreas. These β cells destructions cause hyperglycemic episode affecting the whole body metabolism. To get over this, type 1 diabetic patients need insulin therapy to control the blood glucose level. This research has been done by using rapid acting insulin (lispro), long-acting insulin (glargine) and the combination between them to know the effects of insulin therapy on blood glucose, insulin and glucagon concentrations. Simulation results show that these different types of insulin have different effects on blood glucose concentration. Insulin therapy using lispro shows better blood glucose control after consumption of meals. Glargin gives better blood glucose control between meals and during sleep. Combination between lispro and glargine shows better glycemic control for whole day blood glucose level.

  20. New twist on neuronal insulin receptor signaling in health, disease, and therapeutics.

    Science.gov (United States)

    Wada, Akihiko; Yokoo, Hiroki; Yanagita, Toshihiko; Kobayashi, Hideyuki

    2005-10-01

    Long after the pioneering studies documenting the existence of insulin (year 1967) and insulin receptor (year 1978) in brain, the last decade has witnessed extraordinary progress in the understanding of brain region-specific multiple roles of insulin receptor signalings in health and disease. In the hypothalamus, insulin regulates food intake, body weight, peripheral fat deposition, hepatic gluconeogenesis, reproductive endocrine axis, and compensatory secretion of counter-regulatory hormones to hypoglycemia. In the hippocampus, insulin promotes learning and memory, independent of the glucoregulatory effect of insulin. Defective insulin receptor signalings are associated with the dementia in normal aging and patients with age-related neurodegenerative diseases (e.g., Alzheimer's disease); the cognitive impairment can be reversed with systemic administration of insulin in the euglycemic condition. Intranasal administration of insulin enhances memory and mood and decreases body weight in healthy humans, without causing hypoglycemia. In the hypothalamus, insulin-induced activation of the phosphoinositide 3-kinase pathway followed by opening of ATP-sensitive K+ channel has been shown to be related to multiple effects of insulin. However, the precise molecular mechanisms of insulin's pleiotropic effects still remain obscure. More importantly, much remains unknown about the quality control mechanisms ensuring correct conformational maturation of the insulin receptor, and the cellular mechanisms regulating density of cell surface functional insulin receptors.

  1. High-fat diet-induced insulin resistance does not increase plasma anandamide levels or potentiate anandamide insulinotropic effect in isolated canine islets.

    Science.gov (United States)

    Woolcott, Orison O; Richey, Joyce M; Kabir, Morvarid; Chow, Robert H; Iyer, Malini S; Kirkman, Erlinda L; Stefanovski, Darko; Lottati, Maya; Kim, Stella P; Harrison, L Nicole; Ionut, Viorica; Zheng, Dan; Hsu, Isabel R; Catalano, Karyn J; Chiu, Jenny D; Bradshaw, Heather; Wu, Qiang; Kolka, Cathryn M; Bergman, Richard N

    2015-01-01

    Obesity has been associated with elevated plasma anandamide levels. In addition, anandamide has been shown to stimulate insulin secretion in vitro, suggesting that anandamide might be linked to hyperinsulinemia. To determine whether high-fat diet-induced insulin resistance increases anandamide levels and potentiates the insulinotropic effect of anandamide in isolated pancreatic islets. Dogs were fed a high-fat diet (n = 9) for 22 weeks. Abdominal fat depot was quantified by MRI. Insulin sensitivity was assessed by the euglycemic-hyperinsulinemic clamp. Fasting plasma endocannabinoid levels were analyzed by liquid chromatography-mass spectrometry. All metabolic assessments were performed before and after fat diet regimen. At the end of the study, pancreatic islets were isolated prior to euthanasia to test the in vitro effect of anandamide on islet hormones. mRNA expression of cannabinoid receptors was determined in intact islets. The findings in vitro were compared with those from animals fed a control diet (n = 7). Prolonged fat feeding increased abdominal fat content by 81.3±21.6% (mean±S.E.M, Pcanines, high-fat diet-induced insulin resistance does not alter plasma anandamide levels or further potentiate the insulinotropic effect of anandamide in vitro.

  2. Insulin-loaded poly(epsilon-caprolactone) nanoparticles: efficient, sustained and safe insulin delivery system.

    Science.gov (United States)

    de Araújo, Thiago M; Teixeira, Zaine; Barbosa-Sampaio, Helena C; Rezende, Luiz F; Boschero, Antonio C; Durán, Nelson; Höehr, Nelci F

    2013-06-01

    The aim of this work was to develop an efficient, biodegradable, biocompatible and safe controlled release system using insulin-loaded poly(epsilon-caprolactone) (PCL) nanoparticles. The insulin-loaded PCL nanoparticles were prepared by double emulsion method (water-in-oil-in-water) using Pluronic F68 as emulsifier. Using the double emulsion method a high insulin encapsulation efficiency (90.6 +/-1.6%) with a zeta potential of -29 +/-2.7 mV and average particle size of 796 +/-10.5 nm was obtained. Insulin-loaded PCL nanoparticles showed no toxicity to MIN6 cells. Insulin nanoparticles administered subcutaneously and intraperitoneally in rats reduced glycaemia of basal levels after 15 minutes, and presented a sustainable hypoglycemic effect on insulin-dependent type 1 diabetic rats, showing to be more efficient than unencapsulated insulin. Furthermore, these nanoparticles were not hepatotoxic, as evaluated by the effect over liver cell-death and oxidative stress scavenger system in rats. These results suggest that insulin-loaded PCL nanoparticles prepared by water-in-oil-in-water emulsion method are biocompatible, efficient and safe insulin-delivering system with controlled insulin release, which indicates that it may be a powerful tool for insulin-dependent patients care.

  3. Level of insulin adherence among diabetes mellitus patients in Felege Hiwot Referral Hospital, Bahir Dar, Northwest Ethiopia, 2017: a cross-sectional study.

    Science.gov (United States)

    Tewabe, Tilahun; Kindie, Selamsew

    2018-05-11

    The objective of this study was to know the level of insulin adherence and to identify factors affecting insulin adherence among diabetes mellitus patients in Felege Hiwot Referral Hospital, Bahir Dar, Northwest Ethiopia. Prevalence of insulin adherence was 59.2%. Patients who are married [AOR = 0.3 (0.14-0.7)], have regular health care visit [AOR = 3.3 (1.5-7.5)] and accessing insulin with low cost [AOR = 2.9 (1.3-6.3)] were more likely to adhere insulin therapy than their counterparts. Recommendations to increase insulin adherence were: government and non-governmental organizations, volunteers and concerned bodies should support syringe and needles for diabetes patients, health care providers and responsible bodies should give intensive health education about the effect of stopping insulin medication.

  4. Effects of vitamin D supplementation on insulin sensitivity and androgen levels in vitamin-D-deficient polycystic ovary syndrome patients.

    Science.gov (United States)

    Karadağ, Cihan; Yoldemir, Tevfik; Yavuz, Dilek Gogas

    2018-02-01

    The aim of this study was to identify the effects of vitamin D supplementation on insulin sensitivity and androgen levels in vitamin-D-deficient polycystic ovary syndrome (PCOS) patients. Sixty-seven vitamin-D-deficient (25-hydroxyvitamin D [25(OH)D] levels below 20 ng/mL) PCOS patients and 54 vitamin-D-deficient non-PCOS volunteer subjects matched for age and body mass index were enrolled to this prospective study. All participants were given 50 000 IU/week cholecalciferol orally for 8 weeks and 1500 IU/day for 4 weeks. Insulin sensitivity was calculated with the Matsuda insulin sensitivity index (ISI) based on an oral glucose tolerance test. Matsuda ISI, gonadal hormones (estrogen, testosterone, androstenedione), and 25(OH)D levels were studied before and at the end of the 12th week of vitamin D load. After vitamin D supplementation, serum androstenedione levels had decreased significantly (P = 0.007) and Matsuda ISI values had increased significantly (P = 0.001) in the PCOS group but no significant changes were seen in those parameters in controls. We observed positive correlations between 25(OH)D levels and Matsuda ISI (r = 0.307; P < 0.01), and negative correlations between 25(OH)D levels and total testosterone (r = -0.306; P < 0.01) and androstenedione (r = -0.275; P < 0.01) levels in the PCOS group. Vitamin D supplementation increased insulin sensitivity and decreased androgen levels in vitamin-D-deficient women with PCOS but did not have any effect in vitamin-D-deficient non-PCOS women. These results may indicate the possible role of vitamin D in the complex pathogenesis of PCOS. © 2017 Japan Society of Obstetrics and Gynecology.

  5. Insulin resistance, insulin sensitization and inflammation in polycystic ovarian syndrome

    Directory of Open Access Journals (Sweden)

    Dhindsa G

    2004-04-01

    Full Text Available It is estimated that 5-10% of women of reproductive age have polycystic ovarian syndrome (PCOS. While insulin resistance is not part of the diagnostic criteria for PCOS, its importance in the pathogenesis of PCOS cannot be denied. PCOS is associated with insulin resistance independent of total or fat-free body mass. Post-receptor defects in the action of insulin have been described in PCOS which are similar to those found in obesity and type 2 diabetes. Treatment with insulin sensitizers, metformin and thiazolidinediones, improve both metabolic and hormonal patterns and also improve ovulation in PCOS. Recent studies have shown that PCOS women have higher circulating levels of inflammatory mediators like C-reactive protein, tumour necrosis factor- , tissue plasminogen activator and plasminogen activator inhibitor-1 (PAI-1 . It is possible that the beneficial effect of insulin sensitizers in PCOS may be partly due to a decrease in inflammation.

  6. [Continuous insulin therapy versus multiple insulin injections in the management of type 1 diabetes: a longitutinal study].

    Science.gov (United States)

    Ribeiro, Maria Estela Bellini; Del Roio Liberatore Junior, Raphael; Custodio, Rodrigo; Martinelli Junior, Carlos Eduardo

    2016-01-01

    To compare multiple doses of insulin and continuous insulin infusion therapy as treatment for type 1 diabetes melito. 40 patients with type 1 diabetes melito (21 female) with ages between 10 and 20 years (mean=14.2) and mean duration of diabetes of 7 years used multiple doses of insulin for at least 6 months and after that, continuous insulin infusion therapy for at least 6 months. Each one of the patients has used multiple doses of insulin and continuous insulin infusion therapy. For analysis of HbA1c, mean glycated hemoglobin levels (mHbA1c) were obtained during each treatment period (multiple doses of insulin and continuous insulin infusion therapy period). Although mHbA1c levels were lower during continuous insulin infusion therapy the difference was not statistically significant. During multiple doses of insulin, 14.2% had mHbA1c values below 7.5% vs. 35.71% while on continuous insulin infusion therapy; demonstrating better glycemic control with the use of continuous insulin infusion therapy. During multiple doses of insulin, 15-40 patients have severe hypoglycemic events versus 5-40 continuous insulin infusion therapy. No episodes of ketoacidosis events were recorded. This is the first study with this design comparing multiple doses of insulin and continuous insulin infusion therapy in Brazil showing no significant difference in HbA1c; hypoglycemic events were less frequent during continuous insulin infusion therapy than during multiple doses of insulin and the percentage of patients who achieved a HbA1c less than 7.5% was greater during continuous insulin infusion therapy than multiple doses of insulin therapy. Copyright © 2015 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  7. Massive weight loss restores 24-hour growth hormone release profiles and serum insulin-like growth factor-I levels in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, M H; Hvidberg, A; Juul, A

    1995-01-01

    levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), as well as insulin in obese subjects before and after a massive weight loss. We studied 18 obese subjects (age, 26 +/- 1 yr; body mass index, 40.9 +/- 1.1 kg/m2); 18 normal age-, and sex-matched control subjects; and 9...... using anthropometric measurements and dual energy x-ray absorptiometry scanning (DXA). In the obese subjects, 24-h spontaneous GH release profiles and the GH responses to insulin-induced hypoglycemia and L-arginine as well as basal IGF-I levels and the IGF-I/IGFBP-3 molar ratio were decreased, whereas...

  8. Insulin and insulin-like growth factor-1 increased in preterm neonates following massage therapy.

    Science.gov (United States)

    Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria; Dieter, John N I; Kumar, Adarsh M; Schanberg, Saul; Kuhn, Cynthia

    2008-12-01

    To determine if massage therapy increased serum insulin and insulin-like growth factor-1 (IGF-1) in preterm neonates. Forty-two preterm neonates who averaged 34.6 weeks (M = 29.5 wk gestational age; M birth weight = 1237 g) and were in the "grower" (step-down) nursery were randomly assigned to a massage therapy group (body stroking and passive limb movements for three, 15-minute periods per day for 5 days) or a control group that received the standard nursery care without massage therapy. On Days 1 and 5, the serum collected by clinical heelsticks was also assayed for insulin and IGF-1, and weight gain and kilocalories consumed were recorded daily. Despite similar formula intake, the massaged preterm neonates showed greater increases during the 5-day period in (1) weight gain; (2) serum levels of insulin; and (3) IGF-1. Increased weight gain was significantly correlated with insulin and IGF-1. Previous data suggested that preterm infant weight gain following massage therapy related to increased vagal activity, which suggests decreased stress and gastric motility, which may contribute to more efficient food absorption. The data from this study suggest for the first time that weight gain was also related to increased serum insulin and IGF-1 levels following massage therapy. Preterm infants who received massage therapy not only showed greater weight gain but also a greater increase in serum insulin and IGF-1 levels, suggesting that massage therapy might be prescribed for all growing neonates.

  9. Insulin signaling displayed a differential tissue-specific response to low-dose dihydrotestosterone in female mice.

    Science.gov (United States)

    Andrisse, Stanley; Billings, Katelyn; Xue, Ping; Wu, Sheng

    2018-04-01

    Hyperandrogenemia and hyperinsulinemia are believed to play prominent roles in polycystic ovarian syndrome (PCOS). We explored the effects of low-dose dihydrotestosterone (DHT), a model of PCOS, on insulin signaling in metabolic and reproductive tissues in a female mouse model. Insulin resistance in the energy storage tissues is associated with type 2 diabetes. Insulin signaling in the ovaries and pituitary either directly or indirectly stimulates androgen production. Energy storage and reproductive tissues were isolated and molecular assays were performed. Livers and white adipose tissue (WAT) from DHT mice displayed lower mRNA and protein expression of insulin signaling intermediates. However, ovaries and pituitaries of DHT mice exhibited higher expression levels of insulin signaling genes/proteins. Insulin-stimulated p-AKT levels were blunted in the livers and WAT of the DHT mice but increased or remained the same in the ovaries and pituitaries compared with controls. Glucose uptake decreased in liver and WAT but was unchanged in pituitary and ovary of DHT mice. Plasma membrane GLUTs were decreased in liver and WAT but increased in ovary and pituitary of DHT mice. Skeletal muscle insulin-signaling genes were not lowered in DHT mice compared with control. DHT mice did not display skeletal muscle insulin resistance. Insulin-stimulated glucose transport increased in skeletal muscles of DHT mice compared with controls. DHT mice were hyperinsulinemic. However, the differential mRNA and protein expression pattern was independent of hyperinsulinemia in cultured hepatocytes and pituitary cells. These findings demonstrate a differential effect of DHT on the insulin-signaling pathway in energy storage vs. reproductive tissues independent of hyperinsulinemia.

  10. Insulin resistance and polycystic ovary syndrome.

    Science.gov (United States)

    Galluzzo, Aldo; Amato, Marco Calogero; Giordano, Carla

    2008-09-01

    Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in humans, affecting approximately 7-8% of women of reproductive age. Despite the criteria adopted, PCOS is considered to be a predominantly hyperandrogenetic syndrome and the evaluation of metabolic parameters and insulin sensitivity is not mandatory. Most women with PCOS also exhibit features of the metabolic syndrome, including insulin resistance, obesity and dyslipidaemia. While the association with type 2 diabetes is well established, whether the incidence of cardiovascular disease is increased in women with PCOS remains unclear. Acknowledging the strong impact of insulin-resistance in the genesis of PCOS could be helpful not only to make the diagnosis more robust, but also for conferring better cardiovascular risk prevention. Several current studies support a strong recommendation that women with PCOS should undergo comprehensive evaluation for the metabolic syndrome and recognized cardiovascular risk factors, and receive appropriate treatment as needed. Lifestyle modifications remain the first-line therapy for all obese women with PCOS. However, many of these women do not lose weight easily. Insulin-sensitizing drugs are discussed as a promising and unique therapeutic option for the chronic treatment of PCOS.

  11. Genetically Determined Insulin Resistance is Characterized by Down-Regulation of Mitochondrial Oxidative Metabolism in Human Skeletal Muscle

    DEFF Research Database (Denmark)

    Kristensen, Jonas M; Skov, Vibe; Wojtaszewski, Jørgen

    2010-01-01

    Transcriptional profiling of skeletal muscle from patients with type 2 diabetes and high-risk individuals have demonstrated a co-ordinated down-regulation of oxidative phosphorylation (OxPhos) genes, suggesting a link between insulin resistance and mitochondrial dysfunction. However, whether...... mitochondrial dysfunction is a cause or consequence of insulin resistance remains to be clarified. In the present study, we tested the hypothesis that mitochondrial oxidative metabolism was down-regulated in skeletal muscle of patients with genetically determined insulin resistance. Skeletal muscle biopsies.......02), and complex V (ATP5B; p=0.005). Our data demonstrate that genetically determined insulin resistance is associated with a co-ordinated down-regulation of OxPhos components both at the transcriptional and translational level. These findings suggest that an impaired biological response to insulin in skeletal...

  12. Impact of the growth hormone receptor exon 3 deletion gene polymorphism on glucose metabolism, lipids, and insulin-like growth factor-I levels during puberty

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Aksglaede, Lise; Munch-Andersen, Thor

    2009-01-01

    . PARTICIPANTS: Participants included 142 healthy Caucasian subjects (65 boys) aged 8.5-16.1 yr. Interventions: Standard 2-h oral glucose tolerance tests were preformed. GHR genotypes were determined by multiplex PCR. Main outcome measures were insulin sensitivity, insulin secretion, serum lipids, and IGF......-I levels. RESULTS: Insulin secretion was higher in children and adolescents with a least one GHRd3 allele, even after adjustment for age, sex, pubertal stage, and insulin sensitivity (P = 0.018). Disposition index was higher in GHRd3-positive subjects (P = 0.026). In addition, the GHRd3 allele...... was associated with higher triglyceride (P = 0.028), but not IGF-I levels. CONCLUSION: The presence of at least one GHRd3 allele was associated with higher insulin secretion for a given degree of insulin sensitivity in healthy children and adolescents during puberty. In addition, the presence of the GHRd3 allele...

  13. No Effect of Added Sugar Consumed at Median American Intake Level on Glucose Tolerance or Insulin Resistance.

    Science.gov (United States)

    Lowndes, Joshua; Sinnett, Stephanie S; Rippe, James M

    2015-10-23

    Excess sugar consumption may promote adverse changes in hepatic and total body insulin resistance. Debate continues over the effects of sugars at more typically consumed levels and whether the identity of the sugar consumed is important. In the present study participants (20-60 years old) were randomly assigned to one of five groups, three that consumed low fat milk with added fructose containing sugars in amounts equivalent to the 50th percentile of fructose consumption (US), one which consumed low-fat milk sweetened with glucose, and one unsweetened low-fat milk control group. The intervention lasted ten weeks. In the entire study population there was less than 1 kg increase in weight (73.6 ±13.0 vs. 74.5 ± 13.3 kg, p 0.05). There were no changes in fasting glucose (49 ± 0.4 vs. 5.0 ± 0.5 mmol/L), insulin (56.9 ± 38.9 vs. 61.8 ± 50.0 pmol/L), or insulin resistance, as measured by the Homeostasis Model Assessment method (1.8 ± 1.3 vs. 2.0 ± 1.5, all p > 0.05). These data suggest that added sugar consumed at the median American intake level does not produce changes in measures of insulin sensitivity or glucose tolerance and that no sugar has more deleterious effects than others.

  14. Insulin-like growth factor-1 levels in children with Beta-thalassemia minor

    OpenAIRE

    Mehran Karimi; Hamdollah Karamifar; Nargrs Sobhani

    2008-01-01

    Objective: Growth retardation in children with b-thalassemia major is multifactorial. Some etiologies described for this condition are hemochromatosis, disturbed growth hormone (GH) / insulin growth factor-1 (IGF-1) axis, undernutrition and hypermetabolism. It has also been proven that growth retardation is present in b-thalassemia major children despite regular transfusion and chelation. Our aim was to evaluate the level of IGF-1 in b-thalassemia minor subjects and compare it with that in he...

  15. Dietary Sodium Restriction Decreases Insulin Secretion Without Affecting Insulin Sensitivity in Humans

    Science.gov (United States)

    Byrne, Loretta M.; Yu, Chang; Wang, Thomas J.; Brown, Nancy J.

    2014-01-01

    Context: Interruption of the renin-angiotensin-aldosterone system prevents incident diabetes in high-risk individuals, although the mechanism remains unclear. Objective: To test the hypothesis that activation of the endogenous renin-angiotensin-aldosterone system or exogenous aldosterone impairs insulin secretion in humans. Design: We conducted a randomized, blinded crossover study of aldosterone vs vehicle and compared the effects of a low-sodium versus a high-sodium diet. Setting: Academic clinical research center. Participants: Healthy, nondiabetic, normotensive volunteers. Interventions: Infusion of exogenous aldosterone (0.7 μg/kg/h for 12.5 h) or vehicle during low or high sodium intake. Low sodium (20 mmol/d; n = 12) vs high sodium (160 mmol/d; n = 17) intake for 5–7 days. Main Outcome Measures: Change in acute insulin secretory response assessed during hyperglycemic clamps while in sodium balance during a low-sodium vs high-sodium diet during aldosterone vs vehicle. Results: A low-sodium diet increased endogenous aldosterone and plasma renin activity, and acute glucose-stimulated insulin (−16.0 ± 5.6%; P = .007) and C-peptide responses (−21.8 ± 8.4%; P = .014) were decreased, whereas the insulin sensitivity index was unchanged (−1.0 ± 10.7%; P = .98). Aldosterone infusion did not affect the acute insulin response (+1.8 ± 4.8%; P = .72) or insulin sensitivity index (+2.0 ± 8.8%; P = .78). Systolic blood pressure and serum potassium were similar during low and high sodium intake and during aldosterone infusion. Conclusions: Low dietary sodium intake reduces insulin secretion in humans, independent of insulin sensitivity. PMID:25029426

  16. Impact of laparoscopic sleeve gastrectomy on body mass index, ghrelin, insulin and lipid levels in 100 obese patients

    OpenAIRE

    Hady, Hady Razak; Dadan, Jacek; Go?aszewski, Pawe?; Safiejko, Kamil

    2012-01-01

    Introduction A high percentage of patients benefit from bariatric procedures in terms of metabolic effect and substantial body mass reduction. These procedures improve glucose metabolism leading to the amelioration or complete resolution of type 2 diabetes, reduction of insulin resistance and alleviation of metabolic syndrome effects. Aim To assess the impact of laparoscopic sleeve gastrectomy (LSG) on the plasma levels of ghrelin, insulin, glucose, triglycerides, total cholesterol, high-dens...

  17. Lipid droplets hypertrophy: a crucial determining factor in insulin regulation by adipocytes

    Science.gov (United States)

    Sanjabi, Bahram; Dashty, Monireh; Özcan, Behiye; Akbarkhanzadeh, Vishtaseb; Rahimi, Mehran; Vinciguerra, Manlio; van Rooij, Felix; Al-Lahham, Saad; Sheedfar, Fareeba; van Kooten, Theo G.; Spek, C. Arnold; Rowshani, Ajda T.; van der Want, Johannes; Klaassen, Rene; Sijbrands, Eric; Peppelenbosch, Maikel P.; Rezaee, Farhad

    2015-03-01

    Lipid droplets (LDs) hypertrophy in adipocytes is the main cause of energy metabolic system dysfunction, obesity and its afflictions such as T2D. However, the role of adipocytes in linking energy metabolic disorders with insulin regulation is unknown in humans. Human adipocytes constitutively synthesize and secrete insulin, which is biologically functional. Insulin concentrations and release are fat mass- and LDs-dependent respectively. Fat reduction mediated by bariatric surgery repairs obesity-associated T2D. The expression of genes, like PCSK1 (proinsulin conversion enzyme), GCG (Glucagon), GPLD1, CD38 and NNAT, involved in insulin regulation/release were differentially expressed in pancreas and adipose tissue (AT). INS (insulin) and GCG expression reduced in human AT-T2D as compared to AT-control, but remained unchanged in pancreas in either state. Insulin levels (mRNA/protein) were higher in AT derived from prediabetes BB rats with destructed pancreatic β-cells and controls than pancreas derived from the same rats respectively. Insulin expression in 10 human primary cell types including adipocytes and macrophages is an evidence for extrapancreatic insulin-producing cells. The data suggest a crosstalk between AT and pancreas to fine-tune energy metabolic system or may minimize the metabolic damage during diabetes. This study opens new avenues towards T2D therapy with a great impact on public health.

  18. Elevated resistin levels in cirrhosis are associated with the proinflammatory state and altered hepatic glucose metabolism but not with insulin resistance

    NARCIS (Netherlands)

    Bahr, Matthias J.; Ockenga, Johann; Boeker, Klaus H. W.; Manns, Michael P.; Tietge, Uwe J. F.

    The adipokine resistin has been implicated in obesity and insulin resistance. Liver cirrhosis is associated with decreased body fat mass and insulin resistance. We determined plasma resistin levels in 57 patients with cirrhosis, 13 after liver transplantation, and 30 controls and correlated these

  19. Resveratrol improves high-fat diet induced insulin resistance by rebalancing subsarcolemmal mitochondrial oxidation and antioxidantion.

    Science.gov (United States)

    Haohao, Zhang; Guijun, Qin; Juan, Zheng; Wen, Kong; Lulu, Chen

    2015-03-01

    Although resveratrol (RES) is thought to be a key regulator of insulin sensitivity in rodents, the exact mechanism underlying this effect remains unclear. Therefore, we sought to investigate how RES affects skeletal muscle oxidative and antioxidant levels of subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondrial populations in high-fat diet (HFD)-induced insulin resistance (IR) rats. Systemic and skeletal muscle insulin sensitivity together with expressions of several genes related to mitochondrial biogenesis and skeletal muscle SIRT1, SIRT3 protein levels were studied in rats fed a normal diet, a HFD, and a HFD with intervention of RES for 8 weeks. Oxidative stress levels and antioxidant enzyme activities were assessed in SS and IMF mitochondria. HFD fed rats exhibited obvious systemic and skeletal muscle IR as well as decreased SIRT1 and SIRT3 expressions, mitochondrial DNA (mtDNA), and mitochondrial biogenesis (p diet induced IR, increased SIRT1 and SIRT3 expressions, mtDNA, and mitochondrial biogenesis (p competence in HFD rats.

  20. High serum resistin is associated with an increase in adiposity but not a worsening of insulin resistance in Pima Indians

    DEFF Research Database (Denmark)

    de Courten, Barbora; Degawa-Yamauchi, Mikako; Considine, Robert V

    2004-01-01

    Resistin is an adipokine with putative prodiabetogenic properties. Like other hormones secreted by adipose tissue, resistin is being investigated as a possible etiologic link between excessive adiposity and insulin resistance. Although there is growing evidence that circulating levels...... of this adipokine are proportional to the degree of adiposity, an effect on insulin resistance in humans remains unproven. To evaluate the relations among resistin, obesity, and insulin resistance, we measured fasting serum resistin levels in 113 nondiabetic (75-g oral glucose tolerance test) Pima Indians (ages 29...... +/- 7 years, body fat 31 +/- 8%, resistin 3.7 +/- 1.1 ng/ml [means +/- SD]), who were characterized for body composition (assessed by hydrodensitometry or dual-energy X-ray absorptiometry), whole-body insulin sensitivity (M; assessed by hyperinsulinemic clamp), basal hepatic glucose output (BHGO...

  1. Insulin-induced translocation of IR to the nucleus in insulin responsive cells requires a nuclear translocation sequence.

    Science.gov (United States)

    Kesten, Dov; Horovitz-Fried, Miriam; Brutman-Barazani, Tamar; Sampson, Sanford R

    2018-04-01

    Insulin binding to its cell surface receptor (IR) activates a cascade of events leading to its biological effects. The Insulin-IR complex is rapidly internalized and then is either recycled back to the plasma membrane or sent to lysosomes for degradation. Although most of the receptor is recycled or degraded, a small amount may escape this pathway and migrate to the nucleus of the cell where it might be important in promulgation of receptor signals. In this study we explored the mechanism by which insulin induces IR translocation to the cell nucleus. Experiments were performed cultured L6 myoblasts, AML liver cells and 3T3-L1 adipocytes. Insulin treatment induced a rapid increase in nuclear IR protein levels within 2 to 5 min. Treatment with WGA, an inhibitor of nuclear import, reduced insulin-induced increases nuclear IR protein; IR was, however, translocated to a perinuclear location. Bioinformatics tools predicted a potential nuclear localization sequence (NLS) on IR. Immunofluorescence staining showed that a point mutation on the predicted NLS blocked insulin-induced IR nuclear translocation. In addition, blockade of nuclear IR activation in isolated nuclei by an IR blocking antibody abrogated insulin-induced increases in IR tyrosine phosphorylation and nuclear PKCδ levels. Furthermore, over expression of mutated IR reduced insulin-induced glucose uptake and PKB phosphorylation. When added to isolated nuclei, insulin induced IR phosphorylation but had no effect on nuclear IR protein levels. These results raise questions regarding the possible role of nuclear IR in IR signaling and insulin resistance. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Peripheral insulin resistance and impaired insulin signaling contribute to abnormal glucose metabolism in preterm baboons.

    Science.gov (United States)

    Blanco, Cynthia L; McGill-Vargas, Lisa L; Gastaldelli, Amalia; Seidner, Steven R; McCurnin, Donald C; Leland, Michelle M; Anzueto, Diana G; Johnson, Marney C; Liang, Hanyu; DeFronzo, Ralph A; Musi, Nicolas

    2015-03-01

    Premature infants develop hyperglycemia shortly after birth, increasing their morbidity and death. Surviving infants have increased incidence of diabetes as young adults. Our understanding of the biological basis for the insulin resistance of prematurity and developmental regulation of glucose production remains fragmentary. The objective of this study was to examine maturational differences in insulin sensitivity and the insulin-signaling pathway in skeletal muscle and adipose tissue of 30 neonatal baboons using the euglycemic hyperinsulinemic clamp. Preterm baboons (67% gestation) had reduced peripheral insulin sensitivity shortly after birth (M value 12.5 ± 1.5 vs 21.8 ± 4.4 mg/kg · min in term baboons) and at 2 weeks of age (M value 12.8 ± 2.6 vs 16.3 ± 4.2, respectively). Insulin increased Akt phosphorylation, but these responses were significantly lower in preterm baboons during the first week of life (3.2-fold vs 9.8-fold). Preterm baboons had lower glucose transporter-1 protein content throughout the first 2 weeks of life (8%-12% of term). In preterm baboons, serum free fatty acids (FFAs) did not decrease in response to insulin, whereas FFAs decreased by greater than 80% in term baboons; the impaired suppression of FFAs in the preterm animals was paired with a decreased glucose transporter-4 protein content in adipose tissue. In conclusion, peripheral insulin resistance and impaired non-insulin-dependent glucose uptake play an important role in hyperglycemia of prematurity. Impaired insulin signaling (reduced Akt) contributes to the defect in insulin-stimulated glucose disposal. Counterregulatory hormones are not major contributors.

  3. Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

    Directory of Open Access Journals (Sweden)

    Chugh Dipti

    2010-05-01

    Full Text Available Abstract Background The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. Results A synthetic insulin precursor (IP-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant. Using immobilized metal ion affinity chromatography (IMAC as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth. Conclusions A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture.

  4. Plasma adiponectin levels are increased despite insulin resistance in corticotropin-releasing hormone transgenic mice, an animal model of Cushing syndrome.

    Science.gov (United States)

    Shinahara, Masayuki; Nishiyama, Mitsuru; Iwasaki, Yasumasa; Nakayama, Shuichi; Noguchi, Toru; Kambayashi, Machiko; Okada, Yasushi; Tsuda, Masayuki; Stenzel-Poore, Mary P; Hashimoto, Kozo; Terada, Yoshio

    2009-01-01

    Adiponectin (AdN), an adipokine derived from the adipose tissue, has an insulin-sensitizing effect, and plasma AdN is shown to be decreased in obesity and/or insulin resistant state. To clarify whether changes in AdN are also responsible for the development of glucocorticoid-induced insulin resistance, we examined AdN concentration in plasma and AdN expression in the adipose tissue, using corticotropin-releasing hormone (CRH) transgenic mouse (CRH-Tg), an animal model of Cushing syndrome. We found, unexpectedly, that plasma AdN levels in CRHTg were significantly higher than those in wild-type littermates (wild-type: 19.7+/-2.5, CRH-Tg: 32.4+/-3.1 microg/mL, pAdN mRNA and protein levels were significantly decreased in the adipose tissue of CRH-Tg. Bilateral adrenalectomy in CRH-Tg eliminated both their Cushing's phenotype and their increase in plasma AdN levels (wild-type/sham: 9.4+/-0.5, CRH-Tg/sham: 15.7+/-2.0, CRH-Tg/ADX: 8.5+/-0.4 microg/mL). These results strongly suggest that AdN is not a major factor responsible for the development of insulin resistance in Cushing syndrome. Our data also suggest that glucocorticoid increases plasma AdN levels but decreases AdN expression in adipocytes, the latter being explained possibly by the decrease in AdN metabolism in the Cushing state.

  5. Effects of experimentally induced mild hyperthyroidism on growth hormone and insulin secretion and sex steroid levels in healthy young men.

    Science.gov (United States)

    Lovejoy, J C; Smith, S R; Bray, G A; Veldhuis, J D; Rood, J C; Tulley, R

    1997-12-01

    Although triiodothyronine (T3) exerts major regulatory actions in both animals and humans, most clinical studies of T3 administration have been relatively short-term. The present study examined the effects of more than 2 months (63 days) of low-dose T3 treatment on overnight pulsatile growth hormone (GH) secretion, short-term insulin secretion, and of sex steroid levels in seven healthy, lean men studied at an inpatient metabolic unit. At baseline, there were strong correlations between sex hormone-binding globulin (SHBG) and several measures of GH production, including total GH production (r = .99), GH interburst interval (r = -.75), and GH mass (r = .82). SHBG was also inversely correlated with basal insulin secretion (r = -.74). There was a 42% increase in serum levels of total testosterone (18.5 +/- 1.3 to 26.3 +/- 1.8 nmol/L, P = .005) and a 150% increase in SHBG (18.0 +/- 2.2 to 44.9 +/- 7.0 nmol/L, P = .008) following T3 treatment. Estradiol and free testosterone levels were unchanged by treatment, although free testosterone decreased from 142.8 +/- 18.4 to 137.3 +/- 19.5 pmol/L. T3 treatment significantly reduced the GH interburst interval (P secretion. There were no statistically significant effects of T3 treatment on insulin secretion, although insulin peak amplitude, mass secreted per burst, and total production all decreased. We conclude that experimentally induced T3 excess in healthy men produces significant and sustained changes in sex hormone levels and GH secretion. Furthermore, there are strong associations between SHBG and both GH and insulin secretion independent of thyroid hormone excess that require additional study.

  6. Diabetes, insulin and exercise

    DEFF Research Database (Denmark)

    Richter, Erik; Galbo, H

    1986-01-01

    The metabolic and hormonal adaptations to single exercise sessions and to exercise training in normal man and in patients with insulin-dependent as well as non-insulin-dependent diabetes mellitus are reviewed. In insulin-dependent (type I) diabetes good metabolic control is best obtained...... by a regular pattern of life which will lead to a fairly constant demand for insulin from day to day. Exercise is by nature a perturbation that makes treatment of diabetes difficult: Muscle contractions per se tend to decrease the plasma glucose concentration whereas the exercise-induced response of the so......-called counter-regulatory hormones tend to increase plasma glucose by increasing hepatic glucose production and adipose tissue lipolysis. If the pre-exercise plasma insulin level is high, hypoglycaemia may develop during exercise whereas hyperglycaemia and ketosis may develop if pre-exercise plasma insulin...

  7. Insulin

    Science.gov (United States)

    ... For Consumers Home For Consumers Consumer Information by Audience For Women Women's Health Topics Insulin Share Tweet ... I start having side effects? What is my target blood sugar level? How often should I check ...

  8. Influence of orlistat therapy on serum insulin level and morphological and functional parameters of peripheral arterial circulation in obese patients

    Directory of Open Access Journals (Sweden)

    Hajduković Zoran

    2005-01-01

    Full Text Available Background/Aim. Insulin resistance is related to accelerated atherosclerosis, whereas weight loss is associated with the increasing insulin sensitivity, the improvement of functional and the morphological parameters of arterial circulation, and the reduction of cardiovascular morbidity and mortality. The aim of our study was to evaluate the influence of orlistat treatment on serum insulin level and functional and morphologic parameters of peripheral arterial circulation. Methods. We conducted a prospective, randomized, double − blind, placebo − controlled study. Thirty patients with body mass index over 30 kg/m2 normotensive, nonsmokers, without clinically manifested cardiovascular disease or diabetes were randomly assigned either orlistat (120 mg, 3 times daily; n = 20 or placebo (n = 10 in a double − blind manner. All of the patients were on individually calculated hypocaloric diet. The follow-up period was 24 weeks. Arterial pressure, fasting serum glucose and insulin level, triglycerides, total cholesterol and low density lipoprotein-cholesterol were determined at the beginning, following 3 and 6 months. Also, the intima − media thickness of right superficial femoral artery and the mean blood flow velocity were determined with ultrasonography. Results. Inside the period of 3 and 6 months, there were the greater reductions of body mass index, arterial pressure, fasting glucose and insulin level, total cholesterol, low density lipoproteins, as well as the greater reductions of mean velocity blood flow and peripheral pulse pressure in the orlistat group vs the placebo group (p < 0.01. Greater reductions in the waist circumference and intima − media thickness were registered following 6 months in the orlistat vs the placebo group (p < 0.01. Conclusion. In the group of obese patients orlistat therapy reduced risk factors, serum insulin level and improved early arterial functional changes as assessed with the reductions of the mean

  9. Retinopathy of prematurity and serum level of insulin-like growth factor-1.

    Science.gov (United States)

    Banjac, Lidija; Bokan, Vesna

    2012-06-01

    The aim of our study was to measure and compare serum insulin-like growth factor-1 (IGF-1) levels at postmenstrual age of 33 weeks between preterm infants with and without retinopathy of prematurity (ROP). ROP occurs in two phases. Low serum levels of IGF-1 during ROP phase 1 have been found to correlate with the severity of ROP. ROP phase 2 begins around postmenstrual week 33. We conducted a prospective cohort study to measure serum IGF-1 levels in premature infants at postmenstrual age of 33 weeks. The study included all premature infants (N = 74), gestational age large controlled study with repeated measurement of IGF-1 level in the neonatal period is needed to confirm that restoration of IGF-I level occurs in ROP phase 2, i.e. that the low level of IGF-1 is only a feature of ROP phase 1.

  10. Fructose induced neurogenic hypertension mediated by overactivation of p38 MAPK to impair insulin signaling transduction caused central insulin resistance.

    Science.gov (United States)

    Cheng, Pei-Wen; Lin, Yu-Te; Ho, Wen-Yu; Lu, Pei-Jung; Chen, Hsin-Hung; Lai, Chi-Cheng; Sun, Gwo-Ching; Yeh, Tung-Chen; Hsiao, Michael; Tseng, Ching-Jiunn; Liu, Chun-Peng

    2017-11-01

    Type 2 diabetes are at a high risk of complications related to hypertension, and reports have indicated that insulin levels may be associated with blood pressure (BP). Fructose intake has recently been reported to promote insulin resistance and superoxide formation. The aim of this study is to investigate whether fructose intake can enhance superoxide generation and impair insulin signaling in the NTS and subsequently elevate BP in rats with fructose-induced hypertension. Treatment with fructose for 4 weeks increased the BP, serum fasting insulin, glucose, homeostatic model assessment-insulin resistance, and triglyceride levels and reduced the serum direct high-density lipoprotein level in the fructose group. The Tempol treatment recovered the fructose-induced decrease in nitric oxide production in the NTS. Immunoblotting and immunofluorescence analyses further showed that fructose increased the p38- and fructose-induced phosphorylation of insulin receptor substrate 1 (IRS1 S307 ) and suppressed Akt S473 and neuronal nitric oxide synthase phosphorylation. Similarly, fructose was able to impair insulin sensitivity and increase insulin levels in the NTS. Fructose intake also increased the production of superoxide in the NTS. The results of this study suggest that fructose might induce central insulin resistance and elevate BP by enhancing superoxide production and activating p38 phosphorylation in the NTS. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Munc18-1 Regulates First-phase Insulin Release by Promoting Granule Docking to Multiple Syntaxin Isoforms

    NARCIS (Netherlands)

    Oh, E.; Kalwat, M.A.; Kim, M.J.; Verhage, M.; Thurmond, D.C.

    2012-01-01

    Attenuated levels of the Sec1/Munc18 (SM) protein Munc18-1 in human islet β-cells is coincident with type 2 diabetes, although how Munc18-1 facilitates insulin secretion remains enigmatic. Herein, using conventional Munc18-1

  12. Calcium phosphate-PEG-insulin-casein (CAPIC) particles as oral delivery systems for insulin.

    Science.gov (United States)

    Morçöl, T; Nagappan, P; Nerenbaum, L; Mitchell, A; Bell, S J D

    2004-06-11

    An oral delivery system for insulin was developed and functional activity was tested in a non-obese diabetic (NOD) mice model. Calcium phosphate particles containing insulin was synthesized in the presence of PEG-3350 and modified by aggregating the particles with caseins to obtain the calcium phosphate-PEG-insulin-casein (CAPIC) oral insulin delivery system. Single doses of CAPIC formulation were tested in NOD mice under fasting or fed conditions to evaluate the glycemic activity. The blood glucose levels were monitored every 1-2h for 12h following the treatments using an ACCU CHECK blood glucose monitoring system. Orally administered and subcutaneously injected free insulin solution served as controls in the study. Based on the results obtained we propose that: (1). the biological activity of insulin is preserved in CAPIC formulation; (2). insulin in CAPIC formulations, but not the free insulin, displays a prolonged hypoglycemic effect after oral administration to diabetic mice; (3). CAPIC formulation protects insulin from degradation while passing through the acidic environment of the GI track until it is released in the less acidic environment of the intestines where it can be absorbed in its biologically active form; (4). CAPIC formulation represents a new and unique oral delivery system for insulin and other macromolecules.

  13. Increased abundance of insulin/insulin-like growth factor-I hybrid receptors in skeletal muscle of obese subjects is correlated with in vivo insulin sensitivity.

    Science.gov (United States)

    Federici, M; Porzio, O; Lauro, D; Borboni, P; Giovannone, B; Zucaro, L; Hribal, M L; Sesti, G

    1998-08-01

    We reported that in noninsulin-dependent diabetes melitus (NIDDM) patients expression of insulin/insulin-like growth factor I (IGF-I) hybrid receptors is increased in insulin target tissues. Whether this is a defect associated with NIDDM or represents a generalized abnormality associated with insulin resistant states is still unsettled. To address this, we applied a microwell-based immunoassay to measure abundance of insulin receptors, type 1 IGF receptors, and hybrid receptors in muscle of eight normal and eight obese subjects. Maximal insulin binding to insulin receptors was lower in obese than in control subjects (B/T = 1.8 +/- 0.20 and 2.6 +/- 0.30; P < 0.03, respectively) and was negatively correlated with insulinemia (r = -0.60; P < 0.01). Maximal IGF-I binding to type 1 IGF receptors was higher in obese than in controls (B/T = 1.9 +/- 0.20 and 0.86 +/- 0.10; P < 0.0001, respectively) and was negatively correlated with plasma IGF-I levels (r = -0.69; P < 0.003). Hybrid receptor abundance was higher in obese than in normal subjects (B/T = 1.21 +/- 0.14 and 0.44 +/- 0.06; P < 0.0003, respectively) and was negatively correlated with insulin binding (r = -0.60; P < 0.01) and positively correlated with IGF-I binding (r = 0.92; P < 0.0001). Increased abundance of hybrids was correlated with insulinemia (r = 0.70; P < 0.002) and body mass index (r = 0.71; P < 0.0019), whereas it was negatively correlated with in vivo insulin sensitivity measured by ITT (r = -0.67; P < 0.016). These results indicate that downregulation of insulin receptors or upregulation of type 1 IGF receptors because of changes in plasma insulin and IGF-I levels may result in modifications in hybrid receptor abundance.

  14. No Effect of Added Sugar Consumed at Median American Intake Level on Glucose Tolerance or Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Joshua Lowndes

    2015-10-01

    Full Text Available Excess sugar consumption may promote adverse changes in hepatic and total body insulin resistance. Debate continues over the effects of sugars at more typically consumed levels and whether the identity of the sugar consumed is important. In the present study participants (20–60 years old were randomly assigned to one of five groups, three that consumed low fat milk with added fructose containing sugars in amounts equivalent to the 50th percentile of fructose consumption (US, one which consumed low-fat milk sweetened with glucose, and one unsweetened low-fat milk control group. The intervention lasted ten weeks. In the entire study population there was less than 1 kg increase in weight (73.6 ±13.0 vs. 74.5 ± 13.3 kg, p < 0.001, but the change in weight was comparable among groups (p > 0.05. There were no changes in fasting glucose (49 ± 0.4 vs. 5.0 ± 0.5 mmol/L, insulin (56.9 ± 38.9 vs. 61.8 ± 50.0 pmol/L, or insulin resistance, as measured by the Homeostasis Model Assessment method (1.8 ± 1.3 vs. 2.0 ± 1.5, all p > 0.05. These data suggest that added sugar consumed at the median American intake level does not produce changes in measures of insulin sensitivity or glucose tolerance and that no sugar has more deleterious effects than others.

  15. IGF-1 levels across the spectrum of normal to elevated in acromegaly: relationship to insulin sensitivity, markers of cardiovascular risk and body composition.

    Science.gov (United States)

    Reid, Tirissa J; Jin, Zhezhen; Shen, Wei; Reyes-Vidal, Carlos M; Fernandez, Jean Carlos; Bruce, Jeffrey N; Kostadinov, Jane; Post, Kalmon D; Freda, Pamela U

    2015-12-01

    Activity of acromegaly is gauged by levels of GH and IGF-1 and epidemiological studies demonstrate that their normalization reduces acromegaly's excess mortality rate. However, few data are available linking IGF-1 levels to features of the disease that may relate to cardiovascular (CV) risk. Therefore, we tested the hypothesis that serum IGF-1 levels relative to the upper normal limit relate to insulin sensitivity, serum CV risk markers and body composition in acromegaly. In this prospective, cross-sectional study conducted at a pituitary tumor referral center we studied 138 adult acromegaly patients, newly diagnosed and previously treated surgically, with fasting and post-oral glucose levels of endocrine and CV risk markers and body composition assessed by DXA. Active acromegaly is associated with lower insulin sensitivity, body fat and CRP levels than acromegaly in remission. %ULN IGF-1 strongly predicts insulin sensitivity, better than GH and this persists after adjustment for body fat and lean tissue mass. %ULN IGF-1 also relates inversely to CRP levels and fat mass, positively to lean tissue and skeletal muscle estimated (SM(E)) by DXA, but not to blood pressure, lipids, BMI or waist circumference. Gender interacts with the IGF-1-lean tissue mass relationship. Active acromegaly presents a unique combination of features associated with CV risk, reduced insulin sensitivity yet lower body fat and lower levels of some serum CV risk markers, a pattern that is reversed in remission. %ULN IGF-1 levels strongly predict these features. Given the known increased CV risk of active acromegaly, these findings suggest that of these factors insulin resistance is most strongly related to disease activity and potentially to the increased CV risk of active acromegaly.

  16. Insulin effect on [14C]-valine incorporation and its relation to hexokinase activity in developing brain

    International Nuclear Information System (INIS)

    Pal, N.; Bessman, S.P.

    1988-01-01

    Using minced brain cortex from fetal and postnatal rats, we studied the incorporation of [ 14 C]-valine into protein in the presence of insulin. We also assayed the particle bound and soluble hexokinase in these tissues. Insulin significantly stimulated the incorporation of [ 14 C]-valine into brain proteins from fetal stage upto 2 days of life. After this period the insulin effect was minimal, with no effect by day 5. The particle bound (40,000g pellet) brain hexokinase, on the other hand, remained low till about 2 days of life and then increased to almost adult level by 5 days. Our results show that there is an inverse relation between this anabolic effect of insulin and the particle bound hexokinase activity in the cortex of developing rat brain

  17. The level of menadione redox-cycling in pancreatic β-cells is proportional to the glucose concentration: Role of NADH and consequences for insulin secretion

    Energy Technology Data Exchange (ETDEWEB)

    Heart, Emma [Cellular Dynamics Program, Marine Biological Laboratory, Woods Hole, MA, 02543 (United States); Palo, Meridith; Womack, Trayce [Department of Science, United States Coast Guard Academy, New London, CT, 06320 (United States); Smith, Peter J.S. [Cellular Dynamics Program, Marine Biological Laboratory, Woods Hole, MA, 02543 (United States); Institute for Life Sciences, University of Southampton (United Kingdom); Gray, Joshua P., E-mail: Joshua.p.gray@uscga.edu [Cellular Dynamics Program, Marine Biological Laboratory, Woods Hole, MA, 02543 (United States); Department of Science, United States Coast Guard Academy, New London, CT, 06320 (United States)

    2012-01-15

    Pancreatic β-cells release insulin in response to elevation of glucose from basal (4–7 mM) to stimulatory (8–16 mM) levels. Metabolism of glucose by the β-cell results in the production of low levels of reactive oxygen intermediates (ROI), such as hydrogen peroxide (H{sub 2}O{sub 2}), a newly recognized coupling factor linking glucose metabolism to insulin secretion. However, high and toxic levels of H{sub 2}O{sub 2} inhibit insulin secretion. Menadione, which produces H{sub 2}O{sub 2} via redox cycling mechanism in a dose-dependent manner, was investigated for its effect on β-cell metabolism and insulin secretion in INS-1 832/13, a rat β-cell insulinoma cell line, and primary rodent islets. Menadione-dependent redox cycling and resulting H{sub 2}O{sub 2} production under stimulatory glucose exceeded several-fold those reached at basal glucose. This was paralleled by a differential effect of menadione (0.1–10 μM) on insulin secretion, which was enhanced at basal, but inhibited at stimulatory glucose. Redox cycling of menadione and H{sub 2}O{sub 2} formation was dependent on glycolytically-derived NADH, as inhibition of glycolysis and application of non-glycogenic insulin secretagogues did not support redox cycling. In addition, activity of plasma membrane electron transport, a system dependent in part on glycolytically-derived NADH, was also inhibited by menadione. Menadione-dependent redox cycling was sensitive to the NQO1 inhibitor dicoumarol and the flavoprotein inhibitor diphenylene iodonium, suggesting a role for NQO1 and other oxidoreductases in this process. These data may explain the apparent dichotomy between the stimulatory and inhibitory effects of H{sub 2}O{sub 2} and menadione on insulin secretion. -- Highlights: ► Menadione stimulation or inhibition of insulin secretion is dependent upon applied glucose levels. ► Menadione-dependent H{sub 2}O{sub 2} production is proportional to applied glucose levels. ► Quinone-mediated redox cycling

  18. The level of menadione redox-cycling in pancreatic β-cells is proportional to the glucose concentration: Role of NADH and consequences for insulin secretion

    International Nuclear Information System (INIS)

    Heart, Emma; Palo, Meridith; Womack, Trayce; Smith, Peter J.S.; Gray, Joshua P.

    2012-01-01

    Pancreatic β-cells release insulin in response to elevation of glucose from basal (4–7 mM) to stimulatory (8–16 mM) levels. Metabolism of glucose by the β-cell results in the production of low levels of reactive oxygen intermediates (ROI), such as hydrogen peroxide (H 2 O 2 ), a newly recognized coupling factor linking glucose metabolism to insulin secretion. However, high and toxic levels of H 2 O 2 inhibit insulin secretion. Menadione, which produces H 2 O 2 via redox cycling mechanism in a dose-dependent manner, was investigated for its effect on β-cell metabolism and insulin secretion in INS-1 832/13, a rat β-cell insulinoma cell line, and primary rodent islets. Menadione-dependent redox cycling and resulting H 2 O 2 production under stimulatory glucose exceeded several-fold those reached at basal glucose. This was paralleled by a differential effect of menadione (0.1–10 μM) on insulin secretion, which was enhanced at basal, but inhibited at stimulatory glucose. Redox cycling of menadione and H 2 O 2 formation was dependent on glycolytically-derived NADH, as inhibition of glycolysis and application of non-glycogenic insulin secretagogues did not support redox cycling. In addition, activity of plasma membrane electron transport, a system dependent in part on glycolytically-derived NADH, was also inhibited by menadione. Menadione-dependent redox cycling was sensitive to the NQO1 inhibitor dicoumarol and the flavoprotein inhibitor diphenylene iodonium, suggesting a role for NQO1 and other oxidoreductases in this process. These data may explain the apparent dichotomy between the stimulatory and inhibitory effects of H 2 O 2 and menadione on insulin secretion. -- Highlights: ► Menadione stimulation or inhibition of insulin secretion is dependent upon applied glucose levels. ► Menadione-dependent H 2 O 2 production is proportional to applied glucose levels. ► Quinone-mediated redox cycling is dependent on glycolysis

  19. Differential Effects of Camel Milk on Insulin Receptor Signaling – Towards Understanding the Insulin-like Properties of Camel Milk

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    Abdulrasheed O Abdulrahman

    2016-01-01

    Full Text Available Previous studies on the Arabian camel (Camelus dromedarius showed beneficial effects of its milk reported in diverse models of human diseases including a substantial hypoglycemic activity. However, the cellular and molecular mechanisms involved in such effects remain completely unknown. In this study, we hypothesized that camel milk may act at the level of human insulin receptor (hIR and its related intracellular signaling pathways. Therefore, we examined the effect of camel milk on the activation of hIR transiently expressed in human embryonic kidney 293 (HEK293 cells using bioluminescence resonance energy transfer (BRET technology. BRET was used to assess, in live cells and real-time, the physical interaction between hIR and insulin receptor signaling proteins (IRS1 and the growth factor receptor-bound protein 2 (Grb2. Our data showed that camel milk did not promote any increase in the BRET signal between hIR and IRS1 or Grb2 in the absence of insulin stimulation. However, it significantly potentiated the maximal insulin-promoted BRET signal between hIR and Grb2 but not IRS1. Interestingly, camel milk appears to differentially impact the downstream signaling since it significantly activated ERK1/2 and potentiated the insulin-induced ERK1/2 but not Akt activation. These observations are to some extent consistent with the BRET data since ERK1/2 and Akt activation are known to reflect the engagement of Grb2 and IRS1 pathways, respectively. The preliminary fractionation of camel milk suggests the peptide/protein nature of the active component in camel milk. Together, our study demonstrates for the first time an allosteric effect of camel milk on insulin receptor conformation and activation with differential effects on its intracellular signaling. These findings should help to shed more light on the hypoglycemic activity of camel milk with potential therapeutic applications.

  20. Urea impairs β cell glycolysis and insulin secretion in chronic kidney disease

    Science.gov (United States)

    Koppe, Laetitia; Nyam, Elsa; Vivot, Kevin; Manning Fox, Jocelyn E.; Dai, Xiao-Qing; Nguyen, Bich N.; Attané, Camille; Moullé, Valentine S.; MacDonald, Patrick E.; Ghislain, Julien

    2016-01-01

    Disorders of glucose homeostasis are common in chronic kidney disease (CKD) and are associated with increased mortality, but the mechanisms of impaired insulin secretion in this disease remain unclear. Here, we tested the hypothesis that defective insulin secretion in CKD is caused by a direct effect of urea on pancreatic β cells. In a murine model in which CKD is induced by 5/6 nephrectomy (CKD mice), we observed defects in glucose-stimulated insulin secretion in vivo and in isolated islets. Similarly, insulin secretion was impaired in normal mouse and human islets that were cultured with disease-relevant concentrations of urea and in islets from normal mice treated orally with urea for 3 weeks. In CKD mouse islets as well as urea-exposed normal islets, we observed an increase in oxidative stress and protein O-GlcNAcylation. Protein O-GlcNAcylation was also observed in pancreatic sections from CKD patients. Impairment of insulin secretion in both CKD mouse and urea-exposed islets was associated with reduced glucose utilization and activity of phosphofructokinase 1 (PFK-1), which could be reversed by inhibiting O-GlcNAcylation. Inhibition of O-GlcNAcylation also restored insulin secretion in both mouse models. These results suggest that insulin secretory defects associated with CKD arise from elevated circulating levels of urea that increase islet protein O-GlcNAcylation and impair glycolysis. PMID:27525435

  1. Diastolic dysfunction is associated with insulin resistance, but not with aldosterone level in normotensive offspring of hypertensive families.

    Science.gov (United States)

    Zizek, Bogomir; Poredos, Pavel; Trojar, Andrej; Zeljko, Tadej

    2008-01-01

    We investigated left ventricular (LV) morphology and function in association with insulin level/insulin resistance (IR) and aldosterone level in normotensive offspring of subjects with essential hypertension (familial trait, FT). The study encompassed 76 volunteers of whom 44 were normotensive with FT (aged 28-39 years) and 32 age-matched controls without FT. LV mass and function were measured using conventional echocardiography and tissue Doppler imaging. LV diastolic function was reported as peak septal annular velocities (E(m) and E(m)/A(m) ratio) in tissue Doppler imaging. Fasting insulin and aldosterone were determined. In subjects with FT, the LV mass was higher than in controls (92.14 +/- 24.02 vs. 70.08 +/- 20.58 g; p < 0.001). The study group had a worse LV diastolic function than control subjects (lower E(m) and E(m)/A(m) ratio; p < 0.001). In subjects with FT, the E(m)/A(m) ratio was independently associated with IR (partial p = 0.029 in multivariate model, R(2) = 0.51), but not with LV mass. The aldosterone level was comparable in both groups. In normotensive individuals with FT, LV morphological and functional abnormalities were found. LV dysfunction but not an increase in LV mass is associated with IR. The aldosterone level is probably not responsible for the development of early hypertensive heart disease. (c) 2008 S. Karger AG, Basel.

  2. Insulin Use in Pregnancy: An Update

    OpenAIRE

    Blum, Alyson K.

    2016-01-01

    IN BRIEF Insulin remains the standard of care for the treatment of type 1 diabetes, type 2 diabetes, and uncontrolled gestational diabetes. Tight control maintained in the first trimester and throughout pregnancy plays a vital role in decreasing poor fetal outcomes, including structural anomalies, macrosomia, hypoglycemia of the newborn, adolescent and adult obesity, and diabetes. Understanding new insulin formulations and strengths is important in assessing risks, since no data on their use ...

  3. Analysis of the variation levels of APN, insulin, sensitive C-reactive protein and leptin in the serum of patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Du Tongxing; Wang Zizheng; Wang Shukui; Qi Shaokang; Tao Xiaojun

    2005-01-01

    To study the mechanism of pancreatic 13 cell dysfunction and tissue resistance to insulin, and to provide basis for early diagnosis and therapy of the disease, the levels of APN, insulin, sensitive C-reactive protein and leptin in the serum of patients with type 2 diabetes mellitus were determined. Altogether 184 untreatea type 2 diabetes mellitus patients, 30 normal people as the control group, and another 75 type 2 diabetes mellitus patients who have been treated for a year were enrolled in this study. The serum levels of the above indexes were determined by chemiluminescence immunoassay, enzyme immunoassay and radioimmunoassay. The results showed that there were obvious differences in the levels of insulin, leptin, C-reacting protein and insulin antibody between the normal control group and the group of the untreated type 2 diabetes mellitus patients (P<0.01), especially there was significant difference in the level of APN(P<0. 001). Among the 75 type 2 diabetes meltitus patients who have received a year's treatment, all the indexes except for APN and insulin antibody were decreased statistically, while the APN level was increased significantly (P<0.01) than that before the treatment. The determination of markers of type 2 diabetes mellitus is of great significance for its early diagnosis, therapy, prognosis and mechanism research. (authors)

  4. Fasting insulin, insulin resistance, and risk of cardiovascular or all-cause mortality in non-diabetic adults: a meta-analysis.

    Science.gov (United States)

    Zhang, Xiaohong; Li, Jun; Zheng, Shuiping; Luo, Qiuyun; Zhou, Chunmei; Wang, Chaoyang

    2017-10-31

    Studies on elevated fasting insulin or insulin resistance (IR) and cardiovascular or all-cause mortality risk in non-diabetic individuals have yielded conflicting results. This meta-analysis aimed to evaluate the association of elevated fasting insulin levels or IR as defined by homeostasis model assessment of IR (HOMA-IR) with cardiovascular or all-cause mortality in non-diabetic adults. We searched for relevant studies in PubMed and Emabse databases until November 2016. Only prospective observational studies investigating the association of elevated fasting insulin levels or HOMA-IR with cardiovascular or all-cause mortality risk in non-diabetic adults were included. Risk ratio (RR) with its 95% confidence intervals (CIs) was pooled for the highest compared with the lowest category of fasting insulin levels or HOMA-IR. Seven articles involving 26976 non-diabetic adults were included. The pooled, adjusted RR of all-cause mortality comparing the highest with the lowest category was 1.13 (95% CI: 1.00-1.27; P =0.058) for fasting insulin levels and 1.34 (95% CI: 1.11-1.62; P =0.002) for HOMA-IR, respectively. When comparing the highest with the lowest category, the pooled adjusted RR of cardiovascular mortality was 2.11 (95% CI: 1.01-4.41; P =0.048) for HOMA-IR in two studies and 1.40 (95% CI: 0.49-3.96; P =0.526) for fasting insulin levels in one study. IR as measured by HOMA-IR but not fasting insulin appears to be independently associated with greater risk of cardiovascular or all-cause mortality in non-diabetic adults. However, the association of fasting insulin and HOMA-IR with cardiovascular mortality may be unreliable due to the small number of articles included. © 2017 The Author(s).

  5. High-fat diet-induced insulin resistance does not increase plasma anandamide levels or potentiate anandamide insulinotropic effect in isolated canine islets.

    Directory of Open Access Journals (Sweden)

    Orison O Woolcott

    Full Text Available Obesity has been associated with elevated plasma anandamide levels. In addition, anandamide has been shown to stimulate insulin secretion in vitro, suggesting that anandamide might be linked to hyperinsulinemia.To determine whether high-fat diet-induced insulin resistance increases anandamide levels and potentiates the insulinotropic effect of anandamide in isolated pancreatic islets.Dogs were fed a high-fat diet (n = 9 for 22 weeks. Abdominal fat depot was quantified by MRI. Insulin sensitivity was assessed by the euglycemic-hyperinsulinemic clamp. Fasting plasma endocannabinoid levels were analyzed by liquid chromatography-mass spectrometry. All metabolic assessments were performed before and after fat diet regimen. At the end of the study, pancreatic islets were isolated prior to euthanasia to test the in vitro effect of anandamide on islet hormones. mRNA expression of cannabinoid receptors was determined in intact islets. The findings in vitro were compared with those from animals fed a control diet (n = 7.Prolonged fat feeding increased abdominal fat content by 81.3±21.6% (mean±S.E.M, P<0.01. In vivo insulin sensitivity decreased by 31.3±12.1% (P<0.05, concomitant with a decrease in plasma 2-arachidonoyl glycerol (from 39.1±5.2 to 15.7±2.0 nmol/L but not anandamide, oleoyl ethanolamide, linoleoyl ethanolamide, or palmitoyl ethanolamide. In control-diet animals (body weight: 28.8±1.0 kg, islets incubated with anandamide had a higher basal and glucose-stimulated insulin secretion as compared with no treatment. Islets from fat-fed animals (34.5±1.3 kg; P<0.05 versus control did not exhibit further potentiation of anandamide-induced insulin secretion as compared with control-diet animals. Glucagon but not somatostatin secretion in vitro was also increased in response to anandamide, but there was no difference between groups (P = 0.705. No differences in gene expression of CB1R or CB2R between groups were found.In canines, high-fat diet

  6. Interleukin-6 induces impairment in human subcutaneous adipogenesis in obesity-associated insulin resistance.

    Science.gov (United States)

    Almuraikhy, Shamma; Kafienah, Wael; Bashah, Moataz; Diboun, Ilhame; Jaganjac, Morana; Al-Khelaifi, Fatima; Abdesselem, Houari; Mazloum, Nayef A; Alsayrafi, Mohammed; Mohamed-Ali, Vidya; Elrayess, Mohamed A

    2016-11-01

    A subset of obese individuals remains insulin sensitive by mechanisms as yet unclear. The hypothesis that maintenance of normal subcutaneous (SC) adipogenesis accounts, at least partially, for this protective phenotype and whether it can be abrogated by chronic exposure to IL-6 was investigated. Adipose tissue biopsies were collected from insulin-sensitive (IS) and insulin-resistant (IR) individuals undergoing weight-reduction surgery. Adipocyte size, pre-adipocyte proportion of stromal vascular fraction (SVF)-derived cells, adipogenic capacity and gene expression profiles of isolated pre-adipocytes were determined, along with local in vitro IL-6 secretion. Adipogenic capacity was further assessed in response to exogenous IL-6 application. Despite being equally obese, IR individuals had significantly lower plasma leptin and adiponectin levels and higher IL-6 levels compared with age-matched IS counterparts. Elevated systemic IL-6 in IR individuals was associated with hyperplasia of adipose tissue-derived SVF cells, despite higher frequency of hypertrophied adipocytes. SC pre-adipocytes from these tissues exhibited lower adipogenic capacity accompanied by downregulation of PPARγ (also known as PPARG) and CEBPα (also known as CEBPA) and upregulation of GATA3 expression. Impaired adipogenesis in IR individuals was further associated with increased adipose secretion of IL-6. Treatment of IS-derived SC pre-adipocytes with IL-6 reduced their adipogenic capacity to levels of the IR group. Obesity-associated insulin resistance is marked by impaired SC adipogenesis, mediated, at least in a subset of individuals, by elevated local levels of IL-6. Understanding the molecular mechanisms underlying reduced adipogenic capacity in IR individuals could help target appropriate therapeutic strategies aimed at those at greatest risk of insulin resistance and type 2 diabetes mellitus.

  7. TLR4 and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Jane J. Kim

    2010-01-01

    Full Text Available Chronic inflammation is a key feature of insulin resistance and obesity. Toll-Like Receptor 4 (TLR4, involved in modulating innate immunity, is an important mediator of insulin resistance and its comorbidities. TLR4 contributes to the development of insulin resistance and inflammation through its activation by elevated exogenous ligands (e.g., dietary fatty acids and enteric lipopolysaccharide and endogenous ligands (e.g., free fatty acids which are elevated in obese states. TLR4, expressed in insulin target tissues, activates proinflammatory kinases JNK, IKK, and p38 that impair insulin signal transduction directly through inhibitory phosphorylation of insulin receptor substrate (IRS on serine residues. TLR4 activation also leads to increased transcription of pro-inflammatory genes, resulting in elevation of cytokine, chemokine, reactive oxygen species, and eicosanoid levels that promote further insulin-desensitization within the target cell itself and in other cells via paracrine and systemic effects. Increased understanding of cell type-specific TLR4-mediated effects on insulin action present the opportunity and challenge of developing related therapeutic approaches for improving insulin sensitivity while preserving innate immunity.

  8. Insulin Promotes the Proliferation of Human Umbilical Cord Matrix-Derived Mesenchymal Stem Cells by Activating the Akt-Cyclin D1 Axis

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    Peng Li

    2017-01-01

    Full Text Available Background. The functions of insulin in mesenchymal stem cells (MSC remain poorly understood. Methods. MSC from human umbilical cord matrix (UCM cultured in serum-free media (SFM with or without insulin were subjected to various molecular biological analyses to determine their proliferation and growth states, expression levels of Akt-cyclin D1 signaling molecules, and in vitro differentiation capacities. Results. Insulin accelerated the G1-S cell cycle progression of UCM-MSC and significantly stimulated their proliferation and growth in SFM. The pro-proliferative action of insulin was associated with augmented cyclin D1 and phosphorylated Akt expression levels. Akt inactivation remarkably abrogated insulin-induced increases in cyclin D1 expression and cell proliferation, indicating that insulin enhances the proliferation of UCM-MSC via acceleration of the G1-S transition mediated by the Akt-cyclin D1 pathway. Additionally, the UCM-MSC propagated in SFM supplemented with insulin exhibited similar specific surface antigen profiles and differentiation capacities as those generated in conventional media containing fetal bovine serum. Conclusions. These findings suggest that insulin acts solely to promote UCM-MSC proliferation without affecting their immunophenotype and differentiation potentials and thus have important implications for utilizing insulin to expand clinical-grade MSC in vitro.

  9. Effect of Avocado Soybean Unsaponifiables on Insulin Secretion and Insulin Sensitivity in Patients with Obesity

    Directory of Open Access Journals (Sweden)

    Esperanza Martínez-Abundis

    2013-10-01

    Full Text Available Aim: To evaluate the effect of avocado soybean unsaponifiables (ASU on insulin secretion and insulin sensitivity in patients with obesity. Methods: A randomized, double-blind, placebo-controlled, clinical trial was carried out in 14 obese adult volunteers. After random allocation of the intervention, 7 patients received 300 mg of ASU or placebo during a fasting state for 3 months. A metabolic profile including IL-6 and high-sensitivity C-reactive protein (hs-CRP levels was carried out prior to the intervention. A hyperglycemic-hyperinsulinemic clamp technique was used to assess insulin secretion and insulin sensitivity phases. Mann-Whitney U test and Wilcoxon test were performed for statistical analyses. The study was approved by the local ethics committee of our institution. Results: At baseline, both groups were similar according to clinical and laboratory characteristics. There was no significant difference in insulin secretion and insulin sensitivity with ASU. Conclusions: ASU administration for 3 months did not modify insulin secretion and insulin sensitivity in patients with obesity.

  10. Retinol binding protein 4, obesity, and insulin resistance in adolescents

    Directory of Open Access Journals (Sweden)

    Ronaldi Noor

    2017-02-01

    Full Text Available Background Obesity is a global problem. Even in poor and developing countries, obesity has reached alarming levels. In childhood, obesity may lead to insulin resistance. Retinol binding protein (RBP4, secreted primarily by liver and adipose tissues, was recently proposed as a link between obesity and insulin resistance. The role of RBP4 in pediatric obesity and its relationship with insulin resistance have not been well elucidated. Objective To compare RBP4 levels in obese and lean adolescents and to assess for a relationship between RBP4 levels and insulin resistance. Method This cross-sectional study was conducted in three senior high schools in Padang, West Sumatera, Indonesia. Subjects were adolescents aged 14-18 years, who were obese or normal weight (n=56. We measured subjects’ body mass index (BMI and serum RBP4 concentrations. Insulin resistance was assessed using the homeostasis model assessment of insulin resistance (HOMA-IR index. Results Similar RBP4 levels were found in the obese and normoweight groups (P>0.05. Higher RBP4 levels were found in the insulin resistant compared to the non-insulin resistant group, but the difference was not significant (P > 0.05. Conclusion There is no significant difference in mean RBP4 levels in obese adolescents compared to normoweight adolescents. Nor are mean RBP4 levels significantly different between obese adolescents with and without insulin resistance.

  11. Expression of insulin-like growth factor system components in colorectal tissue and its relation with serum IGF levels

    NARCIS (Netherlands)

    Vrieling, A.; Voskuil, D.W.; Bosma, A.; Majoor, D.M.; Doorn, van J.; Cats, A.; Depla, A.; Timmer, R.; Witteman, B.J.M.; Wesseling, J.; Kampman, E.; van't Veer, L.J.

    2009-01-01

    Context: The insulin-like growth factor (IGF)-system has been implicated in colorectal tumor carcinogenesis. Although both tumor expression levels and serum concentrations of IGF-system components are related to colorectal cancer risk, it is unknown whether IGF levels in tissue and serum are

  12. Expression of insulin-like growth factor system components in colorectal tissue and its relation with serum IGF levels.

    NARCIS (Netherlands)

    Vrieling, A.; Voskuil, D.W.; Bosma, A.; Majoor, D.M.; Doorn, J. van; Cats, A.; Depla, A.C.; Timmer, R.; Witteman, B.J.; Wesseling, J.; Kampman, E.; Veer, L.J. van 't

    2009-01-01

    CONTEXT: The insulin-like growth factor (IGF)-system has been implicated in colorectal tumor carcinogenesis. Although both tumor expression levels and serum concentrations of IGF-system components are related to colorectal cancer risk, it is unknown whether IGF levels in tissue and serum are

  13. Maternal insulin sensitivity is associated with oral glucose-induced changes in fetal brain activity.

    Science.gov (United States)

    Linder, Katarzyna; Schleger, Franziska; Ketterer, Caroline; Fritsche, Louise; Kiefer-Schmidt, Isabelle; Hennige, Anita; Häring, Hans-Ulrich; Preissl, Hubert; Fritsche, Andreas

    2014-06-01

    Fetal programming plays an important role in the pathogenesis of type 2 diabetes. The aim of the present study was to investigate whether maternal metabolic changes during OGTT influence fetal brain activity. Thirteen healthy pregnant women underwent an OGTT (75 g). Insulin sensitivity was determined by glucose and insulin measurements at 0, 60 and 120 min. At each time point, fetal auditory evoked fields were recorded with a fetal magnetoencephalographic device and response latencies were determined. Maternal insulin increased from a fasting level of 67 ± 25 pmol/l (mean ± SD) to 918 ± 492 pmol/l 60 min after glucose ingestion and glucose levels increased from 4.4 ± 0.3 to 7.4 ± 1.1 mmol/l. Over the same time period, fetal response latencies decreased from 297 ± 99 to 235 ± 84 ms (p = 0.01) and then remained stable until 120 min (235 ± 84 vs 251 ± 91 ms, p = 0.39). There was a negative correlation between maternal insulin sensitivity and fetal response latencies 60 min after glucose ingestion (r = 0.68, p = 0.02). After a median split of the group based on maternal insulin sensitivity, fetuses of insulin-resistant mothers showed a slower response to auditory stimuli (283 ± 79 ms) than those of insulin-sensitive mothers (178 ± 46 ms, p = 0.03). Lower maternal insulin sensitivity is associated with slower fetal brain responses. These findings provide the first evidence of a direct effect of maternal metabolism on fetal brain activity and suggest that central insulin resistance may be programmed during fetal development.

  14. Effects of Exercise Training and Weight Loss on Plasma Fetuin-A Levels and Insulin Sensitivity in Overweight Older Men

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    Jacob B. Blumenthal

    2017-01-01

    Full Text Available Aerobic exercise training and weight loss (AEX+WL improves insulin sensitivity in overweight adults; however, the underlying pathways are incompletely understood. Fetuin-A, a hepatokine that inhibits insulin signaling, may be involved in the salutary effects of AEX+WL. Therefore, we examined the effects of 6-month AEX+WL on plasma fetuin-A levels (36–48 hours after the last bout of exercise, aerobic capacity (VO2max, body composition, glucose tolerance, and insulin sensitivity (M in 16 sedentary, overweight-obese older men (age = 60 ± 2 years, BMI = 31 ± 1 kg/m2 with no history of cardiovascular disease or diabetes. At baseline, fetuin-A levels correlated directly with adiposity and had a borderline inverse correlation with M. After AEX+WL, body weight decreased by ~10 kg, while both VO2max and M increased by 16% (P<0.005 for all. Contrary to our hypothesis, plasma fetuin-A levels increased after AEX+WL (1.16 ± 0.10 g/L versus 1.70 ± 0.19 g/L, P=0.006. This increase was unrelated to changes in body composition or glucose metabolism, but directly correlated with changes in VO2max (r=0.57, P<0.05. Thus, in overweight-to-obese older men, AEX+WL appears to increase plasma fetuin-A levels. Although not associated with improvements in insulin sensitivity, this increase in fetuin-A was related to improvements in aerobic capacity and could be representative of the cardioprotective effects of AEX+WL in older men.

  15. Effects of Exercise Training and Weight Loss on Plasma Fetuin-A Levels and Insulin Sensitivity in Overweight Older Men.

    Science.gov (United States)

    Blumenthal, Jacob B; Gitterman, Anna; Ryan, Alice S; Prior, Steven J

    2017-01-01

    Aerobic exercise training and weight loss (AEX+WL) improves insulin sensitivity in overweight adults; however, the underlying pathways are incompletely understood. Fetuin-A, a hepatokine that inhibits insulin signaling, may be involved in the salutary effects of AEX+WL. Therefore, we examined the effects of 6-month AEX+WL on plasma fetuin-A levels (36-48 hours after the last bout of exercise), aerobic capacity (VO 2max ), body composition, glucose tolerance, and insulin sensitivity (M) in 16 sedentary, overweight-obese older men (age = 60 ± 2 years, BMI = 31 ± 1 kg/m 2 ) with no history of cardiovascular disease or diabetes. At baseline, fetuin-A levels correlated directly with adiposity and had a borderline inverse correlation with M. After AEX+WL, body weight decreased by ~10 kg, while both VO 2max and M increased by 16% ( P < 0.005 for all). Contrary to our hypothesis, plasma fetuin-A levels increased after AEX+WL (1.16 ± 0.10 g/L versus 1.70 ± 0.19 g/L, P = 0.006). This increase was unrelated to changes in body composition or glucose metabolism, but directly correlated with changes in VO 2max ( r = 0.57, P < 0.05). Thus, in overweight-to-obese older men, AEX+WL appears to increase plasma fetuin-A levels. Although not associated with improvements in insulin sensitivity, this increase in fetuin-A was related to improvements in aerobic capacity and could be representative of the cardioprotective effects of AEX+WL in older men.

  16. Acupuncture Alters Expression of Insulin Signaling Related Molecules and Improves Insulin Resistance in OLETF Rats

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    Xin-Yu Huang

    2016-01-01

    Full Text Available To determine effect of acupuncture on insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF rats and to evaluate expression of insulin signaling components. Rats were divided into three groups: Sprague-Dawley (SD rats, OLETF rats, and acupuncture+OLETF rats. Acupuncture was subcutaneously applied to Neiguan (PC6, Zusanli (ST36, and Sanyinjiao (SP6; in contrast, acupuncture to Shenshu (BL23 was administered perpendicularly. For Neiguan (PC6 and Zusanli (ST36, needles were connected to an electroacupuncture (EA apparatus. Fasting blood glucose (FPG was measured by glucose oxidase method. Plasma fasting insulin (FINS and serum C peptide (C-P were determined by ELISA. Protein and mRNA expressions of insulin signaling molecules were determined by Western blot and real-time RT-PCR, respectively. OLETF rats exhibit increased levels of FPG, FINS, C-P, and homeostasis model assessment-estimated insulin resistance (HOMA-IR, which were effectively decreased by acupuncture treatment. mRNA expressions of several insulin signaling related molecules IRS1, IRS2, Akt2, aPKCζ, and GLUT4 were decreased in OLETF rats compared to SD controls. Expression of these molecules was restored back to normal levels upon acupuncture administration. PI3K-p85α was increased in OLETF rats; this increase was also reversed by acupuncture treatment. Acupuncture improves insulin resistance in OLETF rats, possibly via regulating expression of key insulin signaling related molecules.

  17. Impact of intensive insulin treatment on the development and consequences of oxidative stress in insulin-dependent diabetes mellitus

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    Kocić Radivoj

    2007-01-01

    Full Text Available Background/Aim. The aim of this study, which included patients with insulin-dependent diabetes mellitus, was to determine the influence of the application of various treatment modalities (intensive or conventional on the total plasma antioxidative capacity and lipid peroxidation intensity expressed as malondialdehyde (MDA level, catalase and xanthine oxidase activity, erythrocyte glutatione reduced concentration (GSH RBC, erythrocyte MDA level (MDA RBC, as well as susceptibility of erythrocyte to H2O2-induced oxidative stress. Methods. This study included 42 patients with insulin-dependent diabetes mellitus. In 24 of the patients intensive insulin treatment was applied using the model of short-acting insulin in each meal and medium- acting insulin before going to bed, while in 18 of the patients conventional insulin treatment was applied in two (morning and evening doses. In the examined patients no presence of diabetes mellitus complications was recorded. The control group included 20 healthy adults out of a blood doner group. The plasma and erythrocytes taken from the blood samples were analyzed immediately. Results. This investigation proved that the application of intensive insulin treatment regime significantly improves total antioxidative plasma capacity as compared to the application of conventional therapy regime. The obtained results showed that the both plasma and lipoproteines apo B MDA increased significantly more in the patients on conventional therapy than in the patients on intensive insulin therapy, most probably due to intensified xanthine oxidase activity. The level of the MDA in fresh erythrocytes did not differ significantly between the groups on intensive and conventional therapy. The level of GSH and catalase activity, however, were significantly reduced in the patients on conventional therapy due to the increased susceptibility to H2O2-induced oxidative stress . Conclusion. The presented study confirmed positive effect of

  18. Effects of chocolate-based products intake on blood glucose, insulin and ghrelin levels and on satiety in young people: a cross-over experimental study.

    Science.gov (United States)

    Zhang, Cai-Xia; Long, Wei-Qing; Ye, Yan-Bin; Lu, Min-Shan; Zhang, Nai-Qi; Xu, Ming; Huang, Jing; Su, Yi-Xiang

    2018-02-19

    This cross-over experimental study aimed to examine the effects of filled chocolate consumption on blood glucose, insulin and ghrelin levels in 20 volunteers. After a one-week run-in period, study participants consumed two chocolate-based products, the tested biscuit or water for 21 days as a morning snack. After a two-week wash-out period, participants consumed another tested food for another 21 days. Each participant consumed all four test foods within an 18-week period. The participants' blood insulin increased slowly after two chocolate-based products intakes on the first day and satiety levels after eating chocolate-based products and the tested biscuit were the same. Chocolate consumption for three weeks had no adverse effects on blood glucose, insulin or ghrelin levels. In conclusion, compared to eating the tested biscuit, 21-day consumption of the tested chocolate-based products had no adverse effects on the blood glucose, insulin and ghrelin levels. This trial is registered with chictr.org.cn: ChiCTR-IOR-16009525.

  19. The Remaining Service Time Upon Reaching a High Level in M/G/1 Queues

    NARCIS (Netherlands)

    de Boer, Pieter-Tjerk; Nicola, V.F.; van Ommeren, Jan C.W.

    The distribution of the remaining service time upon reaching some target level in an M/G/1 queue is of theoretical as well as practical interest. In general, this distribution depends on the initial level as well as on the target level, say, B. Two initial levels are of particular interest, namely,

  20. Intensive insulin therapy improves insulin sensitivity and mitochondrial function in severely burned children.

    Science.gov (United States)

    Fram, Ricki Y; Cree, Melanie G; Wolfe, Robert R; Mlcak, Ronald P; Qian, Ting; Chinkes, David L; Herndon, David N

    2010-06-01

    To institute intensive insulin therapy protocol in an acute pediatric burn unit and study the mechanisms underlying its benefits. Prospective, randomized study. An acute pediatric burn unit in a tertiary teaching hospital. Children, 4-18 yrs old, with total body surface area burned > or =40% and who arrived within 1 wk after injury were enrolled in the study. Patients were randomized to one of two groups. Intensive insulin therapy maintained blood glucose levels between 80 and 110 mg/dL. Conventional insulin therapy maintained blood glucose patients were included in the data analysis consisting of resting energy expenditure, whole body and liver insulin sensitivity, and skeletal muscle mitochondrial function. Studies were performed at 7 days postburn (pretreatment) and at 21 days postburn (posttreatment). Resting energy expenditure significantly increased posttreatment (1476 +/- 124 to 1925 +/- 291 kcal/m(2) x day; p = .02) in conventional insulin therapy as compared with a decline in intensive insulin therapy. Glucose infusion rate was identical between groups before treatment (6.0 +/- 0.8 conventional insulin therapy vs. 6.8 +/- 0.9 mg/kg x min intensive insulin therapy; p = .5). Intensive insulin therapy displayed a significantly higher glucose clamp infusion rate posttreatment (9.1 +/- 1.3 intensive insulin therapy versus 4.8 +/- 0.6 mg/kg x min conventional insulin therapy, p = .005). Suppression of hepatic glucose release was significantly greater in the intensive insulin therapy after treatment compared with conventional insulin therapy (5.0 +/- 0.9 vs. 2.5 +/- 0.6 mg/kg x min; intensive insulin therapy vs. conventional insulin therapy; p = .03). States 3 and 4 mitochondrial oxidation of palmitate significantly improved in intensive insulin therapy (0.9 +/- 0.1 to 1.7 +/- 0.1 microm O(2)/CS/mg protein/min for state 3, p = .004; and 0.7 +/- 0.1 to 1.3 +/- 0.1 microm O(2)/CS/mg protein/min for state 4, p protocol improves insulin sensitivity and mitochondrial

  1. Prenatal exposure to persistent organochlorine pollutants is associated with high insulin levels in 5-year-old girls.

    Science.gov (United States)

    Tang-Péronard, Jeanett L; Heitmann, Berit L; Jensen, Tina K; Vinggaard, Anne M; Madsbad, Sten; Steuerwald, Ulrike; Grandjean, Philippe; Weihe, Pál; Nielsen, Flemming; Andersen, Helle R

    2015-10-01

    Several persistent organochlorine pollutants (POPs) possess endocrine disrupting abilities, thereby potentially leading to an increased risk of obesity and metabolic diseases, especially if the exposure occurs during prenatal life. We have previously found associations between prenatal POP exposures and increased BMI, waist circumference and change in BMI from 5 to 7 years of age, though only among girls with overweight mothers. In the same birth cohort, we investigated whether prenatal POP exposure was associated with serum concentrations of insulin and leptin among 5-year-old children, thus possibly mediating the association with overweight and obesity at 7 years of age. The analyses were based on a prospective Faroese Birth Cohort (n=656), recruited between 1997 and 2000. Major POPs, polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyldichloroethylene (DDE) and hexachlorobenzene (HCB), were measured in maternal pregnancy serum and breast milk. Children were followed-up at the age of 5 years where a non-fasting blood sample was drawn; 520 children (273 boys and 247 girls) had adequate serum amounts available for biomarker analyses by Luminex® technology. Insulin and leptin concentrations were transformed from continuous to binary variables, using the 75th percentile as a cut-off point. Multiple logistic regression was used to investigate associations between prenatal POP exposures and non-fasting serum concentrations of insulin and leptin at age 5 while taking into account confounders. Girls with highest prenatal POP exposure were more likely to have high non-fasting insulin levels (PCBs 4th quartile: OR=3.71; 95% CI: 1.36, 10.01. DDE 4th quartile: OR=2.75; 95% CI: 1.09, 6.90. HCB 4th quartile: OR=1.98; 95% CI: 1.06, 3.69) compared to girls in the lowest quartile. No significant associations were observed with leptin, or among boys. A mediating effect of insulin or leptin on later obesity was not observed. These findings suggest, that for girls, prenatal

  2. Altered expression and insulin-induced trafficking of Na+-K+-ATPase in rat skeletal muscle

    DEFF Research Database (Denmark)

    Galuska, Dana; Kotova, Olga; Barres, Romain

    2009-01-01

    Skeletal muscle Na(+)-K(+)-ATPase plays a central role in the clearance of K(+) from the extracellular fluid, therefore maintaining blood [K(+)]. Na(+)-K(+)-ATPase activity in peripheral tissue is impaired in insulin resistant states. We determined effects of high-fat diet (HFD) and exercise......(+)-K(+)-ATPase activity after 4 wk of HFD. Exercise training restored alpha(1)-, alpha(2)-, and beta(1)-subunit expression and Na(+)-K(+)-ATPase activity to control levels and reduced beta(2)-subunit expression 2.2-fold (P ... phospholemman. Phospholemman mRNA and protein expression were increased after HFD and restored to control levels after ET. Insulin-stimulated translocation of the alpha(2)-subunit to plasma membrane was impaired by HFD, whereas alpha(1)-subunit translocation remained unchanged. Alterations in sodium pump...

  3. Study on the inter-relationship among the changes of serum levels of leptin, insulin and glucagon in patients with DM2 complicated with hypertension

    International Nuclear Information System (INIS)

    Zeng Zhiwei; Yan Songqin; Tan Wei

    2006-01-01

    Objective: To investigate the inter-relationship among the changes of serum leptin, insulin and glucagon levels in patients with type 2 diabetes mellitus (DM2) complicated with hypertension. Methods: Serum leptin, insulin and glucagon levels were, measured with RIA in 30 DM2 patients complicated with hypertension, 30 DM2 patients without hypertension and 30 controls. Results: Serum levels of leptin, insulin and glucagon in all the DM2 patients were significantly higher than those in controls (P<0.01). In addition, the serum levels in DM2 patients with hypertension were significantly higher than those in DM2 patients without hypertension (P<0.05). These levels were positively correlated with the severity of hypertension. Conclusion: The role played by leptin and glucagon in the pathogenesis of type 2 diabetes mellitns should be furthur studied. (authors)

  4. Selective Insulin Resistance in Adipocytes*

    Science.gov (United States)

    Tan, Shi-Xiong; Fisher-Wellman, Kelsey H.; Fazakerley, Daniel J.; Ng, Yvonne; Pant, Himani; Li, Jia; Meoli, Christopher C.; Coster, Adelle C. F.; Stöckli, Jacqueline; James, David E.

    2015-01-01

    Aside from glucose metabolism, insulin regulates a variety of pathways in peripheral tissues. Under insulin-resistant conditions, it is well known that insulin-stimulated glucose uptake is impaired, and many studies attribute this to a defect in Akt signaling. Here we make use of several insulin resistance models, including insulin-resistant 3T3-L1 adipocytes and fat explants prepared from high fat-fed C57BL/6J and ob/ob mice, to comprehensively distinguish defective from unaffected aspects of insulin signaling and its downstream consequences in adipocytes. Defective regulation of glucose uptake was observed in all models of insulin resistance, whereas other major actions of insulin such as protein synthesis and anti-lipolysis were normal. This defect corresponded to a reduction in the maximum response to insulin. The pattern of change observed for phosphorylation in the Akt pathway was inconsistent with a simple defect at the level of Akt. The only Akt substrate that showed consistently reduced phosphorylation was the RabGAP AS160 that regulates GLUT4 translocation. We conclude that insulin resistance in adipose tissue is highly selective for glucose metabolism and likely involves a defect in one of the components regulating GLUT4 translocation to the cell surface in response to insulin. PMID:25720492

  5. Clinical significance of measurement of serum insulin-like growth factor II and adrenomedulion levels in patients with essential hypertension

    International Nuclear Information System (INIS)

    Fan Bifu; Ji Naijun; Mei Yibin; Wang Chengyao; Chen Donghai; Li Fuyuan; Guan Lihua; Gao Meiying

    2003-01-01

    Objective: To investigate the changes of serum levels of insulin-like growth factor II (IGF II) and adrenomedullin (ADM) in patients with essential hypertension. Methods: Serum IGF II and ADM levels were measured in 62 cases of hypertension and 40 controls with RIA. Results: Serum IGF II and ADM levels were significantly bigger in hypertensive patients than those in the controls (t = 4.454, p < 0.01; t = 3.992, p < 0.01). The serum IGF II level was significantly positively correlated to the serum ADM levels (r = 0.379, p < 0.05) and both were significantly positively correlated to the mean arterial pressure (r = 0.346, r = 0.353, p < 0.05) but not with BMI. Serum ADM levels increased gradually as the disease progressed from stage I to stage III (p < 0.05) with levels in stage III markedly higher than those in stage I (p < 0.01). In EH patients with heart and/or brain and/or renal complications the serum ADM levels were significantly higher than those in EH patients without complications (t = 2.050, p < 0.05). Such differences did not exist in the case of IGF II. Conclusion: Serum IGF II and ADM levels were increased markedly in hypertensive patients. These two factors were mutually positively correlated and both were positively correlated to mean arterial pressure. ADM levels increased gradually as the disease progressing but IGF II levels remained stable

  6. Endothelin-1 exacerbates development of hypertension and atherosclerosis in modest insulin resistant syndrome

    International Nuclear Information System (INIS)

    Lin, Yan-Jie; Juan, Chi-Chang; Kwok, Ching-Fai; Hsu, Yung-Pei; Shih, Kuang-Chung; Chen, Chin-Chang; Ho, Low-Tone

    2015-01-01

    Endothelin-1 (ET-1) is known as potent vasoconstrictor, by virtue of its mitogenic effects, and may deteriorate the process of hypertension and atherosclerosis by aggravating hyperplasia and migration in VSMCs. Our previous study demonstrated that insulin infusion caused sequential induction of hyperinsulinemia, hyperendothelinemia, insulin resistance, and then hypertension in rats. However, the underlying mechanism of ET-1 interfere insulin signaling in VSMCs remains unclear. To characterize insulin signaling during modest insulin resistant syndrome, we established and monitored rats by feeding high fructose-diet (HFD) until high blood pressure and modest insulin resistance occurred. To explore the role of ET-1/ET A R during insulin resistance, ET A R expression, ET-1 binding, and insulin signaling were investigated in the HFD-fed rats and cultured A-10 VSMCs. Results showed that high blood pressure, tunica medial wall thickening, plasma ET-1 and insulin, and accompanied with modest insulin resistance without overweight and hyperglycemia occurred in early-stage HFD-fed rats. In the endothelium-denuded aorta from HFD-fed rats, ET A R expression, but not ET B R, and ET-1 binding in aorta were increased. Moreover, decreasing of insulin-induced Akt phosphorylation and increasing of insulin-induced ERK phosphorylation were observed in aorta during modest insulin resistance. Interestingly, in ET-1 pretreated VSMCs, the increment of insulin-induced Akt phosphorylation was decreased whereas the increment of insulin-induced ERK phosphorylation was increased. In addition, insulin potentiated ET-1-induced VSMCs migration and proliferation due to increasing ET-1 binding. ETAR antagonist reversed effects of ET-1 on insulin-induced signaling and VSMCs migration and proliferation. In summary, modest insulin resistance syndrome accompanied with hyperinsulinemia leading to the potentiation on ET-1-induced actions in aortic VSMCs. ET-1 via ET A R pathway suppressed insulin

  7. Evaluation of immunogenicity of LY2963016 insulin glargine compared with Lantus® insulin glargine in patients with type 1 or type 2 diabetes mellitus.

    Science.gov (United States)

    Ilag, L L; Deeg, M A; Costigan, T; Hollander, P; Blevins, T C; Edelman, S V; Konrad, R J; Ortmann, R A; Pollom, R K; Huster, W J; Zielonka, J S; Prince, M J

    2016-02-01

    To compare the immunogenicity profiles and the potential effects on clinical outcomes of LY2963016 insulin glargine (LY IGlar) and Lantus® insulin glargine (IGlar), products with identical primary amino acid sequences, in patients with type 1 or type 2 diabetes mellitus (T1DM or T2DM). To assess immunogenicity, anti-insulin glargine antibodies (measured as percent binding) were compared between treatments in 52-week (open-label) and 24-week (double-blind) randomized studies in total study populations of patients with T1DM (N = 535) and T2DM (N = 756), respectively, and two subgroups of patients with T2DM: insulin-naïve patients and those reporting prestudy IGlar treatment (prior IGlar). Relationships between insulin antibody levels and clinical outcomes were assessed using analysis of covariance and partial correlations. Insulin antibody levels were assessed using Wilcoxon rank sum. Treatment comparisons for treatment-emergent antibody response (TEAR) and incidence of detectable antibodies were analysed using Fisher's exact test. No significant treatment differences were observed for insulin antibody levels, incidence of detectable anti-insulin glargine antibodies, or incidence of TEAR [overall and endpoint, by last-observation-carried-forward (LOCF)] in patients with T1DM or patients with T2DM, including the insulin-naïve subgroup. A statistically significant difference was noted in the overall incidence of detectable antibodies but not at endpoint (LOCF) nor in TEAR for the prior IGlar subgroup of patients with T2DM. Insulin antibody levels were low (Insulin antibody levels or developing TEAR was not associated with clinical outcomes. LY IGlar and IGlar have similar immunogenicity profiles; anti-insulin glargine antibody levels were low for both treatments, with no observed effect on efficacy and safety outcomes. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

  8. Molecular Mechanisms of Chromium in Alleviating Insulin Resistance

    Science.gov (United States)

    Hua, Yinan; Clark, Suzanne; Ren, Jun; Sreejayan, Nair

    2011-01-01

    Type 2 diabetes is often associated with obesity, dyslipidemia, and cardiovascular anomalies and is a major health problem approaching global epidemic proportions. Insulin resistance, a prediabetic condition, precedes the onset of frank type 2 diabetes and offers potential avenues for early intervention to treat the disease. Although lifestyle modifications and exercise can reduce the incidence of diabetes, compliance has proved to be difficult, warranting pharmacological interventions. However, most of the currently available drugs that improve insulin sensitivity have adverse effects. Therefore, attractive strategies to alleviate insulin resistance include dietary supplements. One such supplement is chromium, which has been shown reduce insulin resistance in some, but not all, studies. Furthermore, the molecular mechanisms of chromium in alleviating insulin resistance remain elusive. This review examines emerging reports on the effect of chromium, as well as molecular and cellular mechanisms by which chromium may provide beneficial effects in alleviating insulin resistance. PMID:22423897

  9. A nonsense mutation causing decreased levels of insulin receptor mRNA: Detection by a simplified technique for direct sequencing of genomic DNA amplified by the polymerase chain reaction

    International Nuclear Information System (INIS)

    Kadowaki, T.; Kadowaki, H.; Taylor, S.I.

    1990-01-01

    Mutations in the insulin receptor gene can render the cell resistant to the biological action of insulin. The authors have studied a patient with leprechaunism (leprechaun/Minn-1), a genetic syndrome associated with intrauterine growth retardation and extreme insulin resistance. Genomic DNA from the patient was amplified by the polymerase chain reaction catalyzed by Thermus aquaticus (Taq) DNA polymerase, and the amplified DNA was directly sequenced. A nonsense mutations was identified at codon 897 in exon 14 in the paternal allele of the patient's insulin receptor gene. Levels of insulin receptor mRNA are decreased to <10% of normal in Epstein-Barr virus-transformed lymphoblasts and cultured skin fibroblasts from this patient. Thus, this nonsense mutation appears to cause a decrease in the levels of insulin receptor mRNA. In addition, they have obtained indirect evidence that the patient's maternal allele of the insulin receptor gene contains a cis-acting dominant mutation that also decreases the level of mRNA, but by a different mechanism. The nucleotide sequence of the entire protein-coding domain and the sequences of the intron-exon boundaries for all 22 exons of the maternal allele were normal. Presumably, the mutation in the maternal allele maps elsewhere in the insulin receptor gene. Thus, they conclude that the patient is a compound heterozygote for two cis-acting dominant mutations in the insulin receptor gene: (i) a nonsense mutation in the paternal allel that reduces the level of insulin receptor mRNA and (ii) an as yet unidentified mutation in the maternal allele that either decreases the rate of transcription or decreases the stability of the mRNA

  10. Combining insulins for optimal blood glucose control in type 1 and 2 diabetes: focus on insulin glulisine

    Directory of Open Access Journals (Sweden)

    Heather Ulrich

    2007-07-01

    Full Text Available Heather Ulrich1,4, Benjamin Snyder1,Satish K Garg1,2,31Barbara Davis Center for Childhood Diabetes; 2Department of Medicine; 3Pediatrics; 4Department of Clinical Pharmacy, School of Pharmacy, University of Colorado at Denver and Health Sciences Center, Denver, CO, USAAbstract: Normalization of blood glucose is essential for the prevention of diabetes mellitus (DM-related microvascular and macrovascular complications. Despite substantial literature to support the benefits of glucose lowering and clear treatment targets, glycemic control remains suboptimal for most people with DM in the United States. Pharmacokinetic limitations of conventional insulins have been a barrier to achieving treatment targets secondary to adverse effects such as hypoglycemia and weight gain. Recombinant DNA technology has allowed modification of the insulin molecule to produce insulin analogues that overcome these pharmacokinetic limitations. With time action profiles that more closely mimic physiologic insulin secretion, rapid acting insulin analogues (RAAs reduce post-prandial glucose excursions and hypoglycemia when compared to regular human insulin (RHI. Insulin glulisine (Apidra® is a rapid-acting insulin analogue created by substituting lysine for asparagine at position B3 and glutamic acid for lysine at position B29 on the B chain of human insulin. The quick absorption of insulin glulisine more closely reproduces physiologic first-phase insulin secretion and its rapid acting profile is maintained across patient subtypes. Clinical trials have demonstrated comparable or greater efficacy of insulin glulisine versus insulin lispro or RHI, respectively. Efficacy is maintained even when insulin glulisine is administered post-meal. In addition, glulisine appears to have a more rapid time action profile compared with insulin lispro across various body mass indexes (BMIs. The safety and tolerability profile of insulin glulisine is also comparable to that of insulin

  11. The role of serial measurements of serum insulin-like growth factor 1 levels in the development of retinopathy of prematurity.

    Science.gov (United States)

    Dorum, Bayram Ali; Yılmaz, Cansu Canbolat; Köksal, Nilgün; Özkan, Hilal; Yıldız, Meral; Özmen, Ahmet Tuncer

    2017-03-01

    To determine the role of serum insulin-like growth factor-1 levels in the development of retinopathy of prematurity, which is a major cause of childhood blindness worldwide. We prospectively studied newborn infants born at a postmenstrual age of prematurity screening and follow-up. Retinopathy of prematurity was classified according to the international classification of retinopathy of prematurity. Serum Insulin like growth factor 1 levels were measured serially in blood samples on the 1 st , 3 rd , 7 th , 21 st , and 28 th day. Among the 40 infants, 11 (27.5%) constituted the retinopathy of prematurity group and 29 comprised the non-retinopathy of prematurity group. In the retinopathy of prematurity group, the mean gestational age and birth weight was significantly lower. The demographic features of the study cohort were similar. The duration of mechanical ventilation was significantly greater in the retinopathy of prematurity group compared with the non-retinopathy of prematurity group (p=0.036). In terms of neonatal morbidities such as respiratory distress syndrome, intraventricular hemorrhage, bronchopulmonary dysplasia, patent ductus arteriosus, and necrotizing enterocolitis, no differences were detected between the groups. The mean serum insulin-like growth factor-1 levels in retinopathy of prematurity group were significantly lower than those in the non-retinopathy of prematurity group at each time point (1 st , 3 rd , 7 th , 21 st , and 28 th day of postnatal life) (p=0.001). This study demonstrated the low serum insulin-like growth factor-1 levels was associated with retinopathy of prematurity development.

  12. Reduced plasma adiponectin concentrations may contribute to impaired insulin activation of glycogen synthase in skeletal muscle of patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Højlund, K.; Frystyk, J.; Levin, K.

    2006-01-01

    AIMS/HYPOTHESIS: Circulating levels of adiponectin are negatively associated with multiple indices of insulin resistance, and the concentration is reduced in humans with insulin resistance and type 2 diabetes. However, the mechanisms by which adiponectin improves insulin sensitivity remain unclear...... (ten lean, 21 obese and 20 with type 2 diabetes). RESULTS: Plasma adiponectin was significantly reduced in type 2 diabetic compared with obese and lean subjects. In lean and obese subjects, insulin significantly reduced plasma adiponectin, but this response was blunted in patients with type 2 diabetes...... by improving the capacity to switch from lipid to glucose oxidation and to store glucose as glycogen in response to insulin, and that low adiponectin may contribute to impaired insulin activation of GS in skeletal muscle of patients with type 2 diabetes....

  13. Defective insulin signaling pathway and increased glycogen synthase kinase-3 activity in the brain of diabetic mice: parallels with Alzheimer's disease and correction by insulin.

    Science.gov (United States)

    Jolivalt, C G; Lee, C A; Beiswenger, K K; Smith, J L; Orlov, M; Torrance, M A; Masliah, E

    2008-11-15

    We have evaluated the effect of peripheral insulin deficiency on brain insulin pathway activity in a mouse model of type 1 diabetes, the parallels with Alzheimer's disease (AD), and the effect of treatment with insulin. Nine weeks of insulin-deficient diabetes significantly impaired the learning capacity of mice, significantly reduced insulin-degrading enzyme protein expression, and significantly reduced phosphorylation of the insulin-receptor and AKT. Phosphorylation of glycogen synthase kinase-3 (GSK3) was also significantly decreased, indicating increased GSK3 activity. This evidence of reduced insulin signaling was associated with a concomitant increase in tau phosphorylation and amyloid beta protein levels. Changes in phosphorylation levels of insulin receptor, GSK3, and tau were not observed in the brain of db/db mice, a model of type 2 diabetes, after a similar duration (8 weeks) of diabetes. Treatment with insulin from onset of diabetes partially restored the phosphorylation of insulin receptor and of GSK3, partially reduced the level of phosphorylated tau in the brain, and partially improved learning ability in insulin-deficient diabetic mice. Our data indicate that mice with systemic insulin deficiency display evidence of reduced insulin signaling pathway activity in the brain that is associated with biochemical and behavioral features of AD and that it can be corrected by insulin treatment.

  14. Related Factors of Insulin Resistance in Korean Children: Adiposity and Maternal Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Kang-Sook Lee

    2011-12-01

    Full Text Available Increased adiposity and unhealthy lifestyle augment the risk for type 2 diabetes in children with familial predisposition. Insulin resistance (IR is an excellent clinical marker for identifying children at high risk for type 2 diabetes. This study was conducted to investigate parental, physiological, behavioral and socio-economic factors related to IR in Korean children. This study is a cross-sectional study using data from 111 children aged 7 years and their parents. Homeostasis model assessment of insulin resistance (HOMA-IR was calculated using fasting glucose and insulin level as a marker of IR. All children’s adiposity indices (r = 0.309–0.318, all P-value = 0.001 and maternal levels of fasting insulin (r = 0.285, P-value = 0.003 and HOMA-IR (r = 0.290, P-value = 0.002 were positively correlated with children’s HOMA-IR level. There was no statistical difference of children’s HOMA-IR level according to children’s lifestyle habits and socioeconomic status of families. An increase of 1 percentage point in body fat was related to 2.7% increase in children’s HOMA-IR (P-value < 0.001 and an increase of 1% of maternal level of HOMA-IR was related to 0.2% increase in children’s HOMA-IR (P-value = 0.002. This study shows that children’s adiposity and maternal IR are positively associated with children’s IR.

  15. Concentrated insulins: the new basal insulins

    Directory of Open Access Journals (Sweden)

    Lamos EM

    2016-03-01

    Full Text Available Elizabeth M Lamos,1 Lisa M Younk,2 Stephen N Davis3 1Division of Endocrinology, Diabetes and Nutrition, 2Department of Medicine, University of Maryland School of Medicine, 3Department of Medicine, University of Maryland Medical Center, Baltimore, MD, USA Introduction: Insulin therapy plays a critical role in the treatment of type 1 and type 2 diabetes mellitus. However, there is still a need to find basal insulins with 24-hour coverage and reduced risk of hypoglycemia. Additionally, with increasing obesity and insulin resistance, the ability to provide clinically necessary high doses of insulin at low volume is also needed. Areas covered: This review highlights the published reports of the pharmacokinetic (PK and glucodynamic properties of concentrated insulins: Humulin-R U500, insulin degludec U200, and insulin glargine U300, describes the clinical efficacy, risk of hypoglycemic, and metabolic changes observed, and finally, discusses observations about the complexity of introducing a new generation of concentrated insulins to the therapeutic market. Conclusion: Humulin-R U500 has a similar onset but longer duration of action compared with U100 regular insulin. Insulin glargine U300 has differential PK/pharmacodynamic effects when compared with insulin glargine U100. In noninferiority studies, glycemic control with degludec U200 and glargine U300 is similar to insulin glargine U100 and nocturnal hypoglycemia is reduced. Concentrated formulations appear to behave as separate molecular entities when compared with earlier U100 insulin analog compounds. In the review of available published data, newer concentrated basal insulins may offer an advantage in terms of reduced intraindividual variability as well as reducing the injection burden in individuals requiring high-dose and large volume insulin therapy. Understanding the PK and pharmacodynamic properties of this new generation of insulins is critical to safe dosing, dispensing, and administration

  16. The adipose transcriptional response to insulin is determined by obesity, not insulin sensitivity

    DEFF Research Database (Denmark)

    Rydén, Mikael; Hrydziuszko, Olga; Mileti, Enrichetta

    2016-01-01

    Metabolically healthy obese subjects display preserved insulin sensitivity and a beneficial white adipose tissue gene expression pattern. However, this observation stems from fasting studies when insulin levels are low. We investigated adipose gene expression by 5'Cap-mRNA sequencing in 17 healthy...... non-obese (NO), 21 insulin-sensitive severely obese (ISO), and 30 insulin-resistant severely obese (IRO) subjects, before and 2 hr into a hyperinsulinemic euglycemic clamp. ISO and IRO subjects displayed a clear but globally similar transcriptional response to insulin, which differed from the small...... effects observed in NO subjects. In the obese, 231 genes were altered; 71 were enriched in ISO subjects (e.g., phosphorylation processes), and 52 were enriched in IRO subjects (e.g., cellular stimuli). Common cardio-metabolic risk factors and gender do not influence these findings. This study demonstrates...

  17. The Correlation of Plasma Levels of Apelin-13 with Insulin Resistance Index and Plasma Leptin of Diabetic Male Rats after 8-Week Aerobic Exercise

    Directory of Open Access Journals (Sweden)

    Fahimeh Kazemi

    2015-09-01

    Full Text Available Abstract Background: The physiological role of apelin, an adipokine secreted by adipose tissue, in insulin resistance and type 2 diabetes has been identified. The aim of this study was to determine the correlation of plasma levels of apelin-13 with insulin resistance index (HOMA-IR and plasma leptin of diabetic male rats after 8-week aerobic exercise. Materials and Methods: Peresent study was an experimental study with animal model. Twenty eight diabetic male Wistar rats were divided into 3 groups: Non-diabetic (n=9, control diabetic (n=9 and trained diabetic (n=10. Type 2 diabetes was induced by intraperitoneal injection of nicotinamide and streptozotocin. The trained diabetic rat ran 8-week on treadmill progressively. After the training period, plasma levels of glucose, insulin, leptin and apelin-13 were measured and HOMA-IR was calculated. One-way analysis of variance (ANOVA and Pearson’s correlation were used for analyzing data. p<0.05 was considered to be statistically significant. Results: A significant decrease in plasma levels of glucose, insulin and leptin and HOMA-IR in trained diabetic vs control diabetic rats, a significant increase in plasma levels of apelin in trained diabetic vs non-diabetic and control diabetic rats and a significant negative correlation of plasma levels of apelin with HOMA-IR and plasma leptin in trained diabetic rats was observed. Conclusion: In present study, 8-week aerobic training by improvement of insulin sensitivity (decrease of HOMA-IR and plasma leptin increased plasma levels of apelin-13 in diabetic male rats.

  18. High normal fasting glucose level in obese youth: a marker for insulin resistance and beta cell dysregulation.

    LENUS (Irish Health Repository)

    O'Malley, G

    2010-06-01

    A high but normal fasting plasma glucose level in adults is a risk factor for future development of type 2 diabetes mellitus and cardiovascular disease. We investigated whether normal fasting plasma glucose levels (<5.60 mmol\\/l) are associated with decreases in insulin sensitivity and beta cell function, as well as an adverse cardiovascular profile in obese youth.

  19. Insulin Sensitivity in Adipose and Skeletal Muscle Tissue of Dairy Cows in Response to Dietary Energy Level and 2,4-Thiazolidinedione (TZD.

    Directory of Open Access Journals (Sweden)

    Afshin Hosseini

    Full Text Available The effects of dietary energy level and 2,4-thiazolidinedione (TZD injection on feed intake, body fatness, blood biomarkers and TZD concentrations, genes related to insulin sensitivity in adipose tissue (AT and skeletal muscle, and peroxisome proliferator-activated receptor gamma (PPARG protein in subcutaneous AT (SAT were evaluated in Holstein cows. Fourteen nonpregnant nonlactating cows were fed a control low-energy (CON, 1.30 Mcal/kg diet to meet 100% of estimated nutrient requirements for 3 weeks, after which half of the cows were assigned to a higher-energy diet (OVE, 1.60 Mcal/kg and half of the cows continued on CON for 6 weeks. All cows received an intravenous injection of TZD starting 2 weeks after initiation of dietary treatments and for an additional 2 weeks, which served as the washout period. Cows fed OVE had greater energy intake and body mass than CON, and TZD had no effect during the administration period. The OVE cows had greater TZD clearance rate than CON cows. The lower concentration of nonesterified fatty acids (NEFA and greater concentration of insulin in blood of OVE cows before TZD injection indicated positive energy balance and higher insulin sensitivity. Administration of TZD increased blood concentrations of glucose, insulin, and beta-hydroxybutyrate (BHBA at 2 to 4 weeks after diet initiation, while the concentration of NEFA and adiponectin (ADIPOQ remained unchanged during TZD. The TZD upregulated the mRNA expression of PPARG and its targets FASN and SREBF1 in SAT, but also SUMO1 and UBC9 which encode sumoylation proteins known to down-regulate PPARG expression and curtail adipogenesis. Therefore, a post-translational response to control PPARG gene expression in SAT could be a counteregulatory mechanism to restrain adipogenesis. The OVE cows had greater expression of the insulin sensitivity-related genes IRS1, SLC2A4, INSR, SCD, INSIG1, DGAT2, and ADIPOQ in SAT. In skeletal muscle, where PPARA and its targets

  20. Insulin Sensitivity in Adipose and Skeletal Muscle Tissue of Dairy Cows in Response to Dietary Energy Level and 2,4-Thiazolidinedione (TZD).

    Science.gov (United States)

    Hosseini, Afshin; Tariq, Muhammad Rizwan; Trindade da Rosa, Fernanda; Kesser, Julia; Iqbal, Zeeshan; Mora, Ofelia; Sauerwein, Helga; Drackley, James K; Trevisi, Erminio; Loor, Juan J

    2015-01-01

    The effects of dietary energy level and 2,4-thiazolidinedione (TZD) injection on feed intake, body fatness, blood biomarkers and TZD concentrations, genes related to insulin sensitivity in adipose tissue (AT) and skeletal muscle, and peroxisome proliferator-activated receptor gamma (PPARG) protein in subcutaneous AT (SAT) were evaluated in Holstein cows. Fourteen nonpregnant nonlactating cows were fed a control low-energy (CON, 1.30 Mcal/kg) diet to meet 100% of estimated nutrient requirements for 3 weeks, after which half of the cows were assigned to a higher-energy diet (OVE, 1.60 Mcal/kg) and half of the cows continued on CON for 6 weeks. All cows received an intravenous injection of TZD starting 2 weeks after initiation of dietary treatments and for an additional 2 weeks, which served as the washout period. Cows fed OVE had greater energy intake and body mass than CON, and TZD had no effect during the administration period. The OVE cows had greater TZD clearance rate than CON cows. The lower concentration of nonesterified fatty acids (NEFA) and greater concentration of insulin in blood of OVE cows before TZD injection indicated positive energy balance and higher insulin sensitivity. Administration of TZD increased blood concentrations of glucose, insulin, and beta-hydroxybutyrate (BHBA) at 2 to 4 weeks after diet initiation, while the concentration of NEFA and adiponectin (ADIPOQ) remained unchanged during TZD. The TZD upregulated the mRNA expression of PPARG and its targets FASN and SREBF1 in SAT, but also SUMO1 and UBC9 which encode sumoylation proteins known to down-regulate PPARG expression and curtail adipogenesis. Therefore, a post-translational response to control PPARG gene expression in SAT could be a counteregulatory mechanism to restrain adipogenesis. The OVE cows had greater expression of the insulin sensitivity-related genes IRS1, SLC2A4, INSR, SCD, INSIG1, DGAT2, and ADIPOQ in SAT. In skeletal muscle, where PPARA and its targets orchestrate

  1. Biotinylated liposomes as potential carriers for the oral delivery of insulin.

    Science.gov (United States)

    Zhang, Xingwang; Qi, Jianping; Lu, Yi; He, Wei; Li, Xiaoyang; Wu, Wei

    2014-01-01

    This study aimed to explore biotinylated liposomes (BLPs) as novel carriers to enhance the oral delivery of insulin. Biotinylation was achieved by incorporating biotin-conjugated phospholipids into the liposome membranes. A significant hypoglycemic effect and enhanced absorption were observed after treating diabetic rats with the BLPs with a relative bioavailability of 12.09% and 8.23%, based on the measurement of the pharmacologic effect and the blood insulin level, respectively; this achieved bioavailability was approximately double that of conventional liposomes. The significance of the biotinylation was confirmed by the facilitated absorption of the BLPs through receptor-mediated endocytosis, as well as by the improved physical stability of the liposomes. Increased cellular uptake and quick gastrointestinal transport further verified the ability of the BLPs to enhance absorption. These results provide a proof of concept that BLPs can be used as potential carriers for the oral delivery of insulin. Diabetes remains a major source of mortality in the Western world, and advances in its management are expected to have substantial socioeconomic impact. In this paper, biotinylated liposomes were utilized as carriers of insulin for local delivery, demonstrating the feasibility of this approach in a rat model. © 2014.

  2. Effect of HCV on fasting glucose, fasting insulin and peripheral insulin resistance in first 5 years of infection.

    Science.gov (United States)

    Ahmed, Naeema; Rashid, Amir; Naveed, Abdul Khaliq; Bashir, Qudsia

    2016-02-01

    To assess the effects of hepatitis C virus infection in the first 5 years on fasting glucose, fasting insulin and peripheral insulin resistance. The case-control study was conducted at the Army Medical College, Rawalpindi, from December 2011 to November 2012, and comprised subjects recruited from a government hospital in Rawalpindi. The subjects included known cases of hepatitis C virus infection for at least 5 years, and normal healthy controls. Fasting blood samples of all the subjects were collected and analysed for serum fasting insulin and serum fasting glucose levels. Homeostatic model assessment-Insulin resistance was calculated SPSS 11 was used for statistical analysis. Of the 30 subjects, 20(66.6%) were cases, while 10(33.3%) were controls. Serum fasting glucose mean level in cases was 89.55±9.53 compared to 84.40±9.80 in the controls (p=0.188). The mean serum fasting insulin in controls was 7.52±3.23 and 6.79±3.30 in cases (p=0.567). Homeostatic model assessment-Insulin resistance level in controls was 1.60±0.76 and In the cases it was 1.49±0.74 (p=0.695). Peripheral insulin resistance and development of type 2 diabetes as a complication of hepatitis C virus infection was not likely at least within the first five years of infection.

  3. Impact of metformin versus the prandial insulin secretagogue, repaglinide, on fasting and postprandial glucose and lipid responses in non-obese patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Lund, Søren S; Tarnow, Lise; Frandsen, Merete

    2008-01-01

    metformin than repaglinide (mean (95% confidence intervals), LDL cholesterol difference metformin versus repaglinide: AUC: -0.17 mmol/l (-0.26; -0.08)). AUC differences remained significant after adjusting for fasting levels. CONCLUSIONS: In non-obese T2DM patients, metformin reduced postprandial levels...... of glycaemia, triglycerides and FFA similarly compared to the prandial insulin secretagogue, repaglinide. Furthermore, metformin reduced fasting and postprandial cholesterolaemia and insulinaemia compared with repaglinide. These data support prescription of metformin as the preferred drug in non-obese patients......OBJECTIVE: Non-obese patients with type 2 diabetes (T2DM) are characterized by predominant defective insulin secretion. However, in non-obese T2DM patients, metformin, targeting insulin resistance, is non-inferior to the prandial insulin secretagogue, repaglinide, controlling overall glycaemia (Hb...

  4. The relationship of adrenal androgen level and insulin resistance in polycystic ovary syndrome patients

    International Nuclear Information System (INIS)

    Tan Qingling; Zhang Hui; Chen Biling

    2011-01-01

    Objective: To investigate the relationship between adrenal androgen level and insulin resistance in polycystic ovary syndrome (PCOS) patients. Methods: Twenty-two healthy women and 85 PCOS patients were underwent adrenocorticptropic hormone (ACTH) stimulation test, and 85 PCOS patients were divided into high response-polycystic ovary syndrome (HR-PCOS) group and normal response-polycystic ovary syndrome (NR-PCOS) group. The ratio of serum luteinizing hormone to follicle stimulating hormone (LH/FSH), estradiol (E 2 ), testosterone (T) and progestin (P) were tested by radioimmunoassay method. 17-hydroxy-progesterone (17-OHP), dehydroepiandros-teronesulfate (DHEAS) and androsterone (AD) was tested at 0 and 60 min after an ACTH stimulation test. Body mass index (BMI), waist-to-hip-circumference radio (WHR) and homeostasis modes of assessment for insulin resistence index (HOMA-IR) were also measured. Results: There were 20 cases that 17-OHP levels were higher than normal (HR-PCOS), the other 65 cases were NR-PCOS group. MBI and WHR(MBI: χ 2 =13.874, 14.512, WHR: χ 2 =12.607, 15.153, P all 2 =4.801, 5.326, P all>0.05). HR-PCOS group and NR-PCOS group were significantly higher than the control group for LH/FSH and estradiol (LH/FSH: χ 2 =18.226, 16.327, E2: χ 2 =17.334, 19.261, P all 2 =12.274, P 2 =20.314, 18.492, P all 2 =18.063, 19.214, DHEAS: χ 2 =17.358, 19.355, P all 2 =4.109, 4.362, P all>0.05). AD of HR-PCOS group and NR-PCOS group were higher than control group before and after the ACTH stimulation test (χ 2 =14.062, 16.549, P all 2 =5.541, P>0.05) between the two PCOS groups. Serum cortisol was no difference between HR-PCOS, NR-PCOS and control groups before and after stimulation test. HOMA-IR of HR-PCOS group and NR-PCOS group were higher than control group (χ 2 =19.263, 21.482, P all 2 =13.582, P<0.05). Conclusions: There have significantly higher basal and ACTH-stimulated level of adrenal androgen hyperresponsiveness in PCOS patients. Adrenal androgen

  5. Insulin requirements in non-critically ill hospitalized patients with diabetes and steroid-induced hyperglycemia.

    Science.gov (United States)

    Spanakis, Elias K; Shah, Nina; Malhotra, Keya; Kemmerer, Terri; Yeh, Hsin-Chieh; Golden, Sherita Hill

    2014-04-01

    Steroid-induced hyperglycemia is common in hospitalized patients with diabetes mellitus. Guidelines for glucose management in this setting are lacking. We conducted a retrospective chart review of non-critically ill patients with diabetes receiving steroids, hospitalized from January 2009 to October 2012. Fifty-eight patients were identified from 247 consults. Multivariable linear regression was used to assess median daily insulin requirements of normoglycemic patients compared with hyperglycemic patients. Of the 58 total patients included in our study, 20 achieved normoglycemia during admission (patient-day weighted mean blood glucose [PDWMBG] level = 154 ± 16 mg/dL) and 38 remained hyperglycemic (PDWMBG level = 243 ± 39 mg/dL; P < 0.001). There were no differences between the 2 patient groups in age, sex, race, body weight, renal function, HbA1c level, glucose-altering medications, diabetes type, or disease duration. Following multivariable adjustment, compared with hyperglycemic patients, normoglycemic patients required similar units of basal insulin (median interquartile range [IQR])(23.6 [17.9, 31.2] vs 20.1 [16.5, 24.4]; P = 0.35); higher units of nutritional insulin (45.5 [34.2, 60.4] vs 20.1 [16.4, 24.5]; P < 0.001]; and lower units of correctional insulin (5.8 [4.1, 8.1] vs 13.0 [10.2, 16.5]; P < 0.001]). Patients achieving normoglycemia required a significantly lower percentage of correction insulin (total daily dose [TDD]: 7.4% vs 23.4%; P < 0.001) and a higher percentage of nutritional insulin (TDD: 58.1% vs 36.2%; P <0.001) than hyperglycemic patients. There was no difference in the TDD per kilogram, TDD per milligram hydrocortisone dose, or TDD per milligram hydrocortisone dose per kilogram weight between the 2 groups. The data suggest that non-critically ill patients with hyperglycemia receiving steroids require a higher percentage of TDD insulin therapy as nutritional insulin to achieve normoglycemia.

  6. Clinical study on insulin receptors of mononuclear cells in diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Dalimunthe, D [Hiroshima Univ. (Japan). School of Medicine

    1980-12-01

    /sup 125/I-insulin binding activity to mononuclear cells was studied in 75 noninsulin-dependent diabetic subjects and 31 normal subjects and the following results were obtained. 1. /sup 125/I-insulin binding is directly proportional to the mononuclear cell concentrations. There is a linear increase of specific /sup 125/I-insulin binding. 2. The binding of /sup 125/I-insulin to mononuclear cells is displaced by the increasing concentration of native insulin. 3. The /sup 125/I-insulin degradation in the incubation medium after incubation of mononuclear cells for 24 hours at 4/sup 0/C was almost 5% in this study. 4. The insulin binding activity in diabetic subjects was lower than that in normal subjects (P < 0.001) without any significant difference in affinity constant. 5. The relationship of binding activity to age of diabetics (r = 0.06, N.S), relative body weitht (r = 0.06, N.S) and duration of diabetes from onset was not significant. 6. In untreated noninsulin-dependent diabetics the insulin binding activity was inversely correlated to fasting blood glucose level (r = 0.78, P < 0.001) and slightly inversely correlated to serum insulin level (r = 0.47, P < 0.01). A slight inverse correlation was also observed in serum triglyceride level (r = 0.53, P < 0.01) and in total cholesterol level (r = 0.29, P < 0.05). 7. No significant difference between the binding activity was observed by grade of diabetic retinopathy. 8. After treatment with diet and/or sulfonylurea, the diabetics exhibited a significant increase in insulin binding activity (P < 0.005) but no significant difference in plasma insulin level, body weight and plasma lipid levels was observed.

  7. Heterogeneous response of isolated adult rat heart cells to insulin

    International Nuclear Information System (INIS)

    Haworth, R.A.; Hunter, D.R.; Berkoff, H.A.

    1984-01-01

    3-O-Methylglucose uptake by Ca2+-resistant adult rat heart cells in suspension was measured, free of artifactual inhibitor-insensitive uptake, and with an accuracy of +/- 1.9% pellet water. (Ca2+-resistant cells are cells which retain their original rod-shaped morphology in the presence of physiological levels of Ca2+.) High levels of insulin (10(-6) M) stimulated the rate of 3-O-methylglucose uptake approximately 10-fold. In the presence of low levels of insulin (3 X 10(-11) M, 10(-10) M) uptake was biphasic; it could not be described by a single exponential function within experimental error, but required the sum of two exponentials. Deviation from a single exponential function was not so great with high levels of insulin (10(-6) M) or no insulin. Cell sugar uptake was also investigated using autoradiography of cells which had accumulated [2-14C]deoxyglucose under similar conditions. This showed considerable heterogeneity of 2-deoxyglucose uptake by cells treated with low levels of insulin, but significantly less heterogeneity of 2-deoxyglucose uptake by cells treated with high levels of insulin. It is concluded that the deviation of 3-O-methylglucose uptake from a single exponential observed at low insulin levels can be accounted for in terms of a heterogeneous response of cells to insulin

  8. CCK increases the transport of insulin into the brain.

    Science.gov (United States)

    May, Aaron A; Liu, Min; Woods, Stephen C; Begg, Denovan P

    2016-10-15

    Food intake occurs in bouts or meals, and numerous meal-generated signals have been identified that act to limit the size of ongoing meals. Hormones such as cholecystokinin (CCK) are secreted from the intestine as ingested food is being processed, and in addition to aiding the digestive process, they provide a signal to the brain that contributes to satiation, limiting the size of the meal. The potency of CCK to elicit satiation is enhanced by elevated levels of adiposity signals such as insulin. In the present experiments we asked whether CCK and insulin interact at the level of the blood-brain barrier (BBB). We first isolated rat brain capillary endothelial cells that comprise the BBB and found that they express the mRNA for both the CCK1R and the insulin receptor, providing a basis for a possible interaction. We then administered insulin intraperitoneally to another group of rats and 15min later administered CCK-8 intraperitoneally to half of those rats. After another 15min, CSF and blood samples were obtained and assayed for immunoreactive insulin. Plasma insulin was comparably elevated above baseline in both the CCK-8 and control groups, indicating that the CCK had no effect on circulating insulin levels given these parameters. In contrast, rats administered CCK had CSF-insulin levels that were more than twice as high as those of control rats. We conclude that circulating CCK greatly facilitates the transport of insulin into the brain, likely by acting directly at the BBB. These findings imply that in circumstances in which the plasma levels of both CCK and insulin are elevated, such as during and soon after meals, satiation is likely to be due, in part, to this newly-discovered synergy between CCK and insulin. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

    Directory of Open Access Journals (Sweden)

    R.M. Banin

    2014-09-01

    Full Text Available Ginkgo biloba extract (GbE has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1, protein tyrosine phosphatase 1B (PTP-1B, and protein kinase B (Akt, as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD or a normal fat diet (NFD for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V, and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb. NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment.

  10. Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

    International Nuclear Information System (INIS)

    Banin, R.M.; Hirata, B.K.S.; Andrade, I.S.; Zemdegs, J.C.S.; Clemente, A.P.G.; Dornellas, A.P.S.; Boldarine, V.T.; Estadella, D.; Albuquerque, K.T.; Oyama, L.M.; Ribeiro, E.B.; Telles, M.M.

    2014-01-01

    Ginkgo biloba extract (GbE) has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1), protein tyrosine phosphatase 1B (PTP-1B), and protein kinase B (Akt), as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD) or a normal fat diet (NFD) for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V), and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb). NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment

  11. Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats

    Energy Technology Data Exchange (ETDEWEB)

    Banin, R. M.; Hirata, B. K.S. [Departamento de Ciências Biológicas, Universidade Federal de São Paulo, Diadema, SP (Brazil); Andrade, I. S.; Zemdegs, J. C.S. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Clemente, A. P.G. [Faculdade de Nutrição, Universidade Federal de Alagoas, Maceió, AL (Brazil); Dornellas, A. P.S.; Boldarine, V. T. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Estadella, D. [Departamento de Biociências, Universidade Federal de São Paulo, Baixada Santista, SP (Brazil); Albuquerque, K. T. [Curso de Nutrição, Universidade Federal do Rio de Janeiro, Macaé, RJ (Brazil); Oyama, L. M.; Ribeiro, E. B. [Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Telles, M. M. [Departamento de Ciências Biológicas, Universidade Federal de São Paulo, Diadema, SP (Brazil)

    2014-07-25

    Ginkgo biloba extract (GbE) has been indicated as an efficient medicine for the treatment of diabetes mellitus type 2. It remains unclear if its effects are due to an improvement of the insulin signaling cascade, especially in obese subjects. The aim of the present study was to evaluate the effect of GbE on insulin tolerance, food intake, body adiposity, lipid profile, fasting insulin, and muscle levels of insulin receptor substrate 1 (IRS-1), protein tyrosine phosphatase 1B (PTP-1B), and protein kinase B (Akt), as well as Akt phosphorylation, in diet-induced obese rats. Rats were fed with a high-fat diet (HFD) or a normal fat diet (NFD) for 8 weeks. After that, the HFD group was divided into two groups: rats gavaged with a saline vehicle (HFD+V), and rats gavaged with 500 mg/kg of GbE diluted in the saline vehicle (HFD+Gb). NFD rats were gavaged with the saline vehicle only. At the end of the treatment, the rats were anesthetized, insulin was injected into the portal vein, and after 90s, the gastrocnemius muscle was removed. The quantification of IRS-1, Akt, and Akt phosphorylation was performed using Western blotting. Serum levels of fasting insulin and glucose, triacylglycerols and total cholesterol, and LDL and HDL fractions were measured. An insulin tolerance test was also performed. Ingestion of a hyperlipidic diet promoted loss of insulin sensitivity and also resulted in a significant increase in body adiposity, plasma triacylglycerol, and glucose levels. In addition, GbE treatment significantly reduced food intake and body adiposity while it protected against hyperglycemia and dyslipidemia in diet-induced obesity rats. It also enhanced insulin sensitivity in comparison to HFD+V rats, while it restored insulin-induced Akt phosphorylation, increased IRS-1, and reduced PTP-1B levels in gastrocnemius muscle. The present findings suggest that G. biloba might be efficient in preventing and treating obesity-induced insulin signaling impairment.

  12. Glucose homeostasis in rainbow trout fed a high-carbohydrate diet: metformin and insulin interact in a tissue-dependent manner.

    Science.gov (United States)

    Polakof, S; Moon, T W; Aguirre, P; Skiba-Cassy, S; Panserat, S

    2011-01-01

    Carnivorous fish species such as the rainbow trout (Oncorhynchus mykiss) are considered to be "glucose intolerant" because of the prolonged hyperglycemia experienced after intake of a carbohydrate-enriched meal. In the present study, we use this species to study glucose homeostasis in fish chronically infused with the hypoglycemic agents, insulin, and metformin, and fed with a high proportion of carbohydrates (30%). We analyzed liver, skeletal muscle, and white adipose tissue (WAT), which are insulin- and metformin-specific targets at both the biochemical and molecular levels. Trout infused with the combination of insulin and metformin can effectively utilize dietary glucose at the liver, resulting in lowered glycemia, increased insulin sensitivity, and glucose storage capacity, combined with reduced glucose output. However, in both WAT and skeletal muscle, we observed decreased insulin sensitivity with the combined insulin + metformin treatment, resulting in the absence of changes at the metabolic level in the skeletal muscle and an increased potential for glucose uptake and storage in the WAT. Thus, the poor utilization by rainbow trout of a diet with a high proportion of carbohydrate can at least be partially improved by a combined treatment with insulin and metformin, and the glucose intolerance observed in this species could be, in part, due to some of the downstream components of the insulin and metformin signaling pathways. However, the predominant effects of metformin treatment on the action of insulin in these three tissues thought to be involved in glucose homeostasis remain exclusive in this species.

  13. Apo E isoforms, insulin output and plasma lipid levels in essential hypertension.

    Science.gov (United States)

    Dembińska-Kieć, A; Kawecka-Jaszcz, K; Kwaśniak, M; Guevara, I; Pankiewicz, J; Malczewska-Malec, M; Iwanejko, J; Hartwich, J; Zdzienicka, A; Stochmal, A; Leszczyńska-Gołabek, I

    1998-02-01

    The association between apo E isoforms and insulin output during the oral glucose test (OGTT) in 60 non-diabetic, non-obese patients with essential hypertension and in control subjects (non-obese, non-diabetic normotensive subjects) was estimated. According to low or high insulin output during OGTT, the subjects were divided into the following groups: normotensive subjects with low (NLI) and high (NHI) and hypertensive subjects with low (HLI) and high (HHI) insulin output. The apo E 4/2 phenotype was detected in 32% of hypertensive subjects but not in control subjects. The frequency of apo E 3/2 phenotype in hypertensive subjects was 5% and in normotensive subjects 15%. An increased frequency of phenotype apo E 4/3 was noticed both in HHI (46%) and in NHI (50%) compared with HLI (22%) and NLI (17%) groups. The results suggest that the determination of phenotypes apo E and insulin output may contribute to an early detection of individuals at high risk of hypertension development.

  14. Prolonged hypoglycemic effect in diabetic dogs due to subcutaneous administration of insulin in liposomes

    International Nuclear Information System (INIS)

    Stevenson, R.W.; Patel, H.M.; Parsons, J.A.; Ryman, B.E.

    1982-01-01

    The biologic action of insulin entrapped in liposomes (phospholipid vesicles) has been investigated following subcutaneous injection to dogs made diabetic with a combination of alloxan and streptozotocin. The fate of the liposomally entrapped material was determined by injecting rats subcutaneously with either 125 I-insulin or the labeled polysaccharide 14 C-inulin, incorporated in liposomes labeled with 3 H-cholesterol. Injection of liposome insulin (0.75 U/kg) to five diabetic dogs resulted in a mean (+/- SEM) blood glucose fall from 16.4 +/- 0.8 to 2.9 +/- 0.4 mmol/L. The glucose level had still not returned to baseline after 24 h and, correspondingly, immunoreactive insulin (IRI) could still be detected in frozen and thawed plasma 24 h after injection. In contrast, the hypoglycemic effect of the same dose of free insulin with or without empty liposomes virtually ended within 8 h and IRI levels returned to baseline by 3 h after injection. In experiments on rats with liposomally entrapped 125 I-insulin or 14 C-inulin the proportion of the injected dose of tracer recoverable by excision of the injection site remained constant after about 1 h and 70% of the dose was still fixed in subcutaneous tissue for at least 5 h thereafter. When the plasma collected 3 h after subcutaneous injection of labeled liposomes containing 125 I-insulin was passed through a column of Sepharose 6B, 50-75% of the 125 I-activity was found in the fractions associated with intact liposomes. One possibility for the persistence of the hypoglycemic effect and of measurable IRI following injection of liposome insulin could be the presence of intact liposomes in the circulation for many hours after adsorption had ceased

  15. High-fat diet with stress impaired islets' insulin secretion by reducing plasma estradiol and pancreatic GLUT2 protein levels in rats' proestrus phase.

    Science.gov (United States)

    Salimi, M; Zardooz, H; Khodagholi, F; Rostamkhani, F; Shaerzadeh, F

    2016-10-01

    This study was conducted to determine whether two estrus phases (proestrus and diestrus) in female rats may influence the metabolic response to a high-fat diet and/or stress, focusing on pancreatic insulin secretion and content. Animals were divided into high-fat and normal diet groups, then each group was subdivided into stress and non-stress groups, and finally, each one of these was divided into proestrus and diestrus subgroups. At the end of high-fat diet treatment, foot-shock stress was applied to the animals. Then, blood samples were taken to measure plasma factors. Finally, the pancreas was removed for determination of glucose transporter 2 (GLUT2) protein levels and assessment of insulin content and secretion of the isolated islets. In the normal and high-fat diet groups, stress increased plasma corticosterone concentration in both phases. In both study phases, high-fat diet consumption decreased estradiol and increased leptin plasma levels. In the high-fat diet group in response to high glucose concentration, a reduction in insulin secretion was observed in the proestrus phase compared with the same phase in the normal diet group in the presence and absence of stress. Also, high-fat diet decreased the insulin content of islets in the proestrus phase compared with the normal diet. High-fat diet and/or stress caused a reduction in islet GLUT2 protein levels in both phases. In conclusion, it seems possible that high-fat diet alone or combined with foot-shock, predispose female rats to impaired insulin secretion, at least in part, by interfering with estradiol levels in the proestrus phase and decreasing pancreatic GLUT2 protein levels.

  16. Insulin-like factor 3 serum levels in 135 normal men and 85 men with testicular disorders

    DEFF Research Database (Denmark)

    Bay, K; Hartung, S; Ivell, R

    2005-01-01

    Insulin-like factor 3 (INSL3) serum levels were measured in 135 andrologically well-characterized normal men and 85 patients with testicular disorders to investigate how the hormone, which is a major secretory product of human Leydig cells, is related to testosterone (T), LH, and semen quality. I...

  17. The level of menadione redox-cycling in pancreatic β-cells is proportional to the glucose concentration: role of NADH and consequences for insulin secretion.

    Science.gov (United States)

    Heart, Emma; Palo, Meridith; Womack, Trayce; Smith, Peter J S; Gray, Joshua P

    2012-01-15

    Pancreatic β-cells release insulin in response to elevation of glucose from basal (4-7mM) to stimulatory (8-16mM) levels. Metabolism of glucose by the β-cell results in the production of low levels of reactive oxygen intermediates (ROI), such as hydrogen peroxide (H(2)O(2)), a newly recognized coupling factor linking glucose metabolism to insulin secretion. However, high and toxic levels of H(2)O(2) inhibit insulin secretion. Menadione, which produces H(2)O(2) via redox cycling mechanism in a dose-dependent manner, was investigated for its effect on β-cell metabolism and insulin secretion in INS-1 832/13, a rat β-cell insulinoma cell line, and primary rodent islets. Menadione-dependent redox cycling and resulting H(2)O(2) production under stimulatory glucose exceeded several-fold those reached at basal glucose. This was paralleled by a differential effect of menadione (0.1-10μM) on insulin secretion, which was enhanced at basal, but inhibited at stimulatory glucose. Redox cycling of menadione and H(2)O(2) formation was dependent on glycolytically-derived NADH, as inhibition of glycolysis and application of non-glycogenic insulin secretagogues did not support redox cycling. In addition, activity of plasma membrane electron transport, a system dependent in part on glycolytically-derived NADH, was also inhibited by menadione. Menadione-dependent redox cycling was sensitive to the NQO1 inhibitor dicoumarol and the flavoprotein inhibitor diphenylene iodonium, suggesting a role for NQO1 and other oxidoreductases in this process. These data may explain the apparent dichotomy between the stimulatory and inhibitory effects of H(2)O(2) and menadione on insulin secretion. Published by Elsevier Inc.

  18. Insulin Induces an Increase in Cytosolic Glucose Levels in 3T3-L1 Cells with Inhibited Glycogen Synthase Activation

    Directory of Open Access Journals (Sweden)

    Helena H. Chowdhury

    2014-10-01

    Full Text Available Glucose is an important source of energy for mammalian cells and enters the cytosol via glucose transporters. It has been thought for a long time that glucose entering the cytosol is swiftly phosphorylated in most cell types; hence the levels of free glucose are very low, beyond the detection level. However, the introduction of new fluorescence resonance energy transfer-based glucose nanosensors has made it possible to measure intracellular glucose more accurately. Here, we used the fluorescent indicator protein (FLIPglu-600µ to monitor cytosolic glucose dynamics in mouse 3T3-L1 cells in which glucose utilization for glycogen synthesis was inhibited. The results show that cells exhibit a low resting cytosolic glucose concentration. However, in cells with inhibited glycogen synthase activation, insulin induced a robust increase in cytosolic free glucose. The insulin-induced increase in cytosolic glucose in these cells is due to an imbalance between the glucose transported into the cytosol and the use of glucose in the cytosol. In untreated cells with sensitive glycogen synthase activation, insulin stimulation did not result in a change in the cytosolic glucose level. This is the first report of dynamic measurements of cytosolic glucose levels in cells devoid of the glycogen synthesis pathway.

  19. PTP1B deficiency improves hypothalamic insulin sensitivity resulting in the attenuation of AgRP mRNA expression under high-fat diet conditions.

    Science.gov (United States)

    Sugiyama, Mariko; Banno, Ryoichi; Mizoguchi, Akira; Tominaga, Takashi; Tsunekawa, Taku; Onoue, Takeshi; Hagiwara, Daisuke; Ito, Yoshihiro; Morishita, Yoshiaki; Iwama, Shintaro; Goto, Motomitsu; Suga, Hidetaka; Arima, Hiroshi

    2017-06-17

    Hypothalamic insulin receptor signaling regulates energy balance and glucose homeostasis via agouti-related protein (AgRP). While protein tyrosine phosphatase 1B (PTP1B) is classically known to be a negative regulator of peripheral insulin signaling by dephosphorylating both insulin receptor β (IRβ) and insulin receptor substrate, the role of PTP1B in hypothalamic insulin signaling remains to be fully elucidated. In the present study, we investigated the role of PTP1B in hypothalamic insulin signaling using PTP1B deficient (KO) mice in vivo and ex vivo. For the in vivo study, hypothalamic insulin resistance induced by a high-fat diet (HFD) improved in KO mice compared to wild-type (WT) mice. Hypothalamic AgRP mRNA expression levels were also significantly decreased in KO mice independent of body weight changes. In an ex vivo study using hypothalamic organotypic cultures, insulin treatment significantly increased the phosphorylation of both IRβ and Akt in the hypothalamus of KO mice compared to WT mice, and also significantly decreased AgRP mRNA expression levels in KO mice. While incubation with inhibitors of phosphatidylinositol-3 kinase (PI3K) had no effect on basal levels of Akt phosphorylation, these suppressed insulin induction of Akt phosphorylation to almost basal levels in WT and KO mice. The inhibition of the PI3K-Akt pathway blocked the downregulation of AgRP mRNA expression in KO mice treated with insulin. These data suggest that PTP1B acts on the hypothalamic insulin signaling via the PI3K-Akt pathway. Together, our results suggest a deficiency of PTP1B improves hypothalamic insulin sensitivity resulting in the attenuation of AgRP mRNA expression under HFD conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Baseline Levels, and Changes Over Time in Body Mass Index and Fasting Insulin, and Their Relationship to Change in Metabolic Trait Clustering

    Science.gov (United States)

    Sullivan, Lisa M.; Fox, Caroline S.; Wilson, Peter W.F.; Nathan, David M.; Vasan, Ramachandran S.; D'Agostino, Ralph B.; Meigs, James B.

    2014-01-01

    Abstract Background: Multiple abnormal metabolic traits are found together or “cluster” within individuals more often than is predicted by chance. The individual and combined role of adiposity and insulin resistance (IR) on metabolic trait clustering is uncertain. We tested the hypothesis that change in trait clustering is a function of both baseline level and change in these measures. Methods: In 2616 nondiabetic Framingham Offspring Study participants, body mass index (BMI) and fasting insulin were related to a within-person 7-year change in a trait score of 0–4 Adult Treatment Panel III metabolic syndrome traits (hypertension, high triglycerides, low high-density lipoprotein cholesterol, hyperglycemia). Results: At baseline assessment, mean trait score was 1.4 traits, and 7-year mean (SEM) change in trait score was +0.25 (0.02) traits, Pfasting insulin were similarly related to trait score change. In models adjusted for age–sex–baseline cluster score, 7-year change in trait score was significantly related to both a 1-quintile difference in baseline BMI (0.07 traits) and fasting insulin (0.18 traits), and to both a 1-quintile 7-year increase in BMI (0.21 traits) and fasting insulin (0.18 traits). Conclusions: Change in metabolic trait clustering was significantly associated with baseline levels and changes in both BMI and fasting insulin, highlighting the importance of both obesity and IR in the clustering of metabolic traits. PMID:25007010

  1. Endothelin-1 exacerbates development of hypertension and atherosclerosis in modest insulin resistant syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yan-Jie [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China); Juan, Chi-Chang [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Kwok, Ching-Fai [Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Hsu, Yung-Pei [Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China); Shih, Kuang-Chung [Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Chen, Chin-Chang [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Ho, Low-Tone, E-mail: ltho@vghtpe.gov.tw [Institute of Physiology, National Yang-Ming University, Taipei, Taiwan (China); Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan (China)

    2015-05-08

    Endothelin-1 (ET-1) is known as potent vasoconstrictor, by virtue of its mitogenic effects, and may deteriorate the process of hypertension and atherosclerosis by aggravating hyperplasia and migration in VSMCs. Our previous study demonstrated that insulin infusion caused sequential induction of hyperinsulinemia, hyperendothelinemia, insulin resistance, and then hypertension in rats. However, the underlying mechanism of ET-1 interfere insulin signaling in VSMCs remains unclear. To characterize insulin signaling during modest insulin resistant syndrome, we established and monitored rats by feeding high fructose-diet (HFD) until high blood pressure and modest insulin resistance occurred. To explore the role of ET-1/ET{sub A}R during insulin resistance, ET{sub A}R expression, ET-1 binding, and insulin signaling were investigated in the HFD-fed rats and cultured A-10 VSMCs. Results showed that high blood pressure, tunica medial wall thickening, plasma ET-1 and insulin, and accompanied with modest insulin resistance without overweight and hyperglycemia occurred in early-stage HFD-fed rats. In the endothelium-denuded aorta from HFD-fed rats, ET{sub A}R expression, but not ET{sub B}R, and ET-1 binding in aorta were increased. Moreover, decreasing of insulin-induced Akt phosphorylation and increasing of insulin-induced ERK phosphorylation were observed in aorta during modest insulin resistance. Interestingly, in ET-1 pretreated VSMCs, the increment of insulin-induced Akt phosphorylation was decreased whereas the increment of insulin-induced ERK phosphorylation was increased. In addition, insulin potentiated ET-1-induced VSMCs migration and proliferation due to increasing ET-1 binding. ETAR antagonist reversed effects of ET-1 on insulin-induced signaling and VSMCs migration and proliferation. In summary, modest insulin resistance syndrome accompanied with hyperinsulinemia leading to the potentiation on ET-1-induced actions in aortic VSMCs. ET-1 via ET{sub A}R pathway

  2. Long-term corticosterone exposure decreases insulin sensitivity and induces depressive-like behaviour in the C57BL/6NCrl mouse.

    Directory of Open Access Journals (Sweden)

    Eva L van Donkelaar

    Full Text Available Chronic stress or long-term administration of glucocorticoids disrupts the hypothalamus-pituitary-adrenal system leading to continuous high levels of glucocorticoids and insulin resistance (IR. This pre-diabetic state can eventually develop into type 2 diabetes mellitus and has been associated with a higher risk to develop depressive disorders. The mechanisms underlying the link between chronic stress, IR and depression remains unclear. The present study aimed to establish a stress-depression model in mice to further study the effects of stress-induced changes upon insulin sensitivity and behavioural consequences. A pilot study was conducted to establish the optimal administration route and a pragmatic measurement of IR. Subsequently, 6-month-old C57BL/6NCrl mice were exposed to long-term oral corticosterone treatment via the drinking water. To evaluate insulin sensitivity changes, blood glucose and plasma insulin levels were measured at different time-points throughout treatment and mice were behaviourally assessed in the elevated zero maze (EZM, forced swimming test (FST and open field test to reveal behavioural changes. Long-term corticosterone treatment increased body weight and decreased insulin sensitivity. The latter was revealed by a higher IR index and increased insulin in the plasma, whereas blood glucose levels remained unchanged. Corticosterone treatment induced longer immobility times in the FST, reflecting depressive-like behaviour. No effects were observed upon anxiety as measured in the EZM. The effect of the higher body weight of the CORT treated animals at time of testing did not influence behaviour in the EZM or FST, as no differences were found in general locomotor activity. Long-term corticosterone treatment via the drinking water reduces insulin sensitivity and induces depressive-like behaviour in the C57BL/6 mouse. This mouse model could thus be used to further explore the underlying mechanisms of chronic stress-induced T2

  3. Barriers towards insulin therapy in type 2 diabetic patients: results of an observational longitudinal study

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    Kulzer Bernd

    2010-10-01

    Full Text Available Abstract Background The course of barriers towards insulin therapy was analysed in three different groups of type 2 diabetic patients. This observational longitudinal study surveyed a three-month follow-up. Methods Participants in this study totalled 130 type 2 diabetic patients. The first subgroup was on insulin therapy at baseline (group 1: n = 57, age 55.6 ± 8.7 yrs, disease duration 12.7 ± 7.2 yrs, HbA1c 8.5 ± 1.6% and remained on insulin at follow-up. Of an initial 73 insulin-naïve patients, 44 were switched to insulin therapy (group 2: age 58.1 ± 6.8 yrs, disease duration 7.7 ± 5.0 yrs, HbA1c 9.1 ± 1.7% and 29 patients remained on an oral regimen (group 3: age 52.7 ± 10.7 yrs, disease duration 5.3 ± 4.6 yrs, HbA1c 8.3 ± 1.4%. Barriers towards insulin therapy were measured using the Insulin Treatment Appraisal Scale (ITAS. As generic instruments of health related quality of life patients completed also the Problem Areas of Diabetes Questionnaire (PAID, the WHO-5 Well-Being Scale (WHO-5, the Centre for Epidemiologic Studies Depression Scale (CES-D and the Trait Version of the State Trait Anxiety Inventory (STAI at baseline and at three-month follow-up. Results At the three-month follow-up, HbA1c had improved in all three groups (7.7 ± 1.2% vs. 7.1 ± 1.1% vs. 6.7 ± 0.8%. The course of negative appraisal of insulin therapy was significantly different in the three groups (p > .003: the ITAS score increased in patients remained on oral antidiabetic drugs (51.2 ± 12.2 to 53.6 ± 12.3, whereas it decreased in patients switched to insulin therapy (49.2 ± 9.8 to 46.2 ± 9.9 or remained on insulin treatment (45.8 ± 8.3 to 44.5 ± 8.0. Diabetes-related distress, trait anxiety, and well-being, showed a similar course in all three groups. The depression score improved significantly in patients switched to insulin treatment compared with patients remaining on insulin therapy. Conclusions In summary, this study suggests that a negative

  4. Insulin production rate in normal man as an estimate for calibration of continuous intravenous insulin infusion in insulin-dependent diabetic patients.

    Science.gov (United States)

    Waldhäusl, W K; Bratusch-Marrain, P R; Francesconi, M; Nowotny, P; Kiss, A

    1982-01-01

    This study examines the feasibility of deriving the 24-h insulin requirement of insulin-dependent diabetic patients who were devoid of any endogenous insulin release (IDD) from the insulin-production rate (IPR) of healthy man (basal, 17 mU/min; stimulated 1.35 U/12.5 g glucose). To this end, continuous intravenous insulin infusion (CIVII) was initiated at a precalculated rate of 41.2 +/- 4.6 (SD) U/24 h in IDD (N - 12). Blood glucose profiles were compared with those obtained during intermittent subcutaneous (s.c.) insulin therapy (IIT) and those of healthy controls (N = 7). Regular insulin (Hoechst CS) was infused with an adapted Mill Hill Infuser at a basal infusion rate of 1.6 U/h (6:00 a.m. to 8:00 p.m.), and of 0.8 U/h from 8:00 p.m. to 6:00 a.m. Preprandial insulin (3.2-6.4 U) was added for breakfast, lunch, and dinner. Daily individual food intake totaled 7688 +/- 784 kJ (1836 +/- 187 kcal)/24 h including 184 +/- 37 g of glucose. Proper control of blood glucose (BG) (mean BG 105 +/- 10 mg/dl; mean amplitude of glycemic excursions 54 +/- 18 mg/dl; and 1 h postprandial BG levels not exceeding 160 mg/dl) and of plasma concentrations of beta-hydroxybutyrate and lactate was maintained by 41.4 +/- 4.4 U insulin/24 h. Although BG values only approximated the upper normal range as seen in healthy controls, they were well within the range reported by others during CIVII. Therefore, we conclude that in adult IDD completely devoid of endogenous insulin (1) the IPR of normal man can be used during CIVII as an estimate for the patient's minimal insulin requirement per 24 h, and (2) this approach allows for a blood glucose profile close to the upper range of a normal control group. Thus, deriving a patient's daily insulin dose from the insulin production rate of healthy man may add an additional experimental protocol which aids in making general calculations of a necessary insulin dose instead of using trial and error or a closed-loop insulin infusion system.

  5. Levels of betatrophin decrease during pregnancy despite increased insulin resistance, beta-cell function and triglyceride levels.

    Science.gov (United States)

    Zielińska, A; Maciulewski, R; Siewko, K; Popławska-Kita, A; Lipińska, D; Kozłowska, G; Górska, M; Szelachowska, M

    2016-12-01

    Evidence in support of an association between betatrophin and insulin resistance (IR) is mounting, with studies demonstrating that betatrophin is elevated in patients with type 2 diabetes, obesity and gestational diabetes. The aim of this study was to evaluate the role of betatrophin in IR and physiological proliferation of beta cells during pregnancy in healthy women. Eighty healthy pregnant women were examined at each trimester [T1 (first), T2 (second), T3 (third)], with a subgroup (n=45) that was also examined at 3 months postpartum (3MPP). The controls comprised 30 non-pregnant healthy women (HW) of reproductive age. Also measured were levels of betatrophin (ELISA), glucose (enzymatic method with hexokinase), insulin (IRMA), C-peptide (EASIA) and HbA 1c (HPLC), while HOMA-IR and HOMA-β scores were calculated. Betatrophin concentration was highest at T1, and differed significantly from T2 and T3 (1.84 [Q 1 =1.16, Q 3 =2.67]ng/mL vs 1.46 [Q 1 =0.96, Q 3 =2.21]ng/mL; Pindex scores increased during gestation, peaking at T3 (2.3 [Q 1 =1.66, Q 3 =2.72] and 227.7 [Q 1 =185.49, Q 3 =326.31], respectively) and returning to levels similar to those of HW at 3MPP (1.53 [Q 1 =1.12, Q 3 =2.41] and 88.86 [Q 1 =62.73, Q 3 =130.45] vs 1.35 [Q 1 =1.02, Q 3 =1.62] and 92.5 [Q 1 =74.20, Q 3 =111.47], respectively). Concentrations of betatrophin decrease during pregnancy, suggesting that the hormone does not play a significant role in the expansion of beta-cell mass and IR during pregnancy. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  6. Brain natriuretic peptide and insulin resistance in older adults.

    Science.gov (United States)

    Kim, F; Biggs, M L; Kizer, J R; Brutsaert, E F; de Filippi, C; Newman, A B; Kronmal, R A; Tracy, R P; Gottdiener, J S; Djoussé, L; de Boer, I H; Psaty, B M; Siscovick, D S; Mukamal, K J

    2017-02-01

    Higher levels of brain natriuretic peptide (BNP) have been associated with a decreased risk of diabetes in adults, but whether BNP is related to insulin resistance in older adults has not been established. N-terminal of the pro hormone brain natriuretic peptide (NT-pro BNP) was measured among Cardiovascular Health Study participants at the 1989-1990, 1992-1993 and 1996-1997 examinations. We calculated measures of insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), Gutt index, Matsuda index] from fasting and 2-h concentrations of glucose and insulin among 3318 individuals with at least one measure of NT-proBNP and free of heart failure, coronary heart disease and chronic kidney disease, and not taking diabetes medication. We used generalized estimating equations to assess the cross-sectional association of NT-proBNP with measures of insulin resistance. Instrumental variable analysis with an allele score derived from nine genetic variants (single nucleotide polymorphisms) within or near the NPPA and NPPB loci was used to estimate an un-confounded association of NT-proBNP levels on insulin resistance. Lower NT-proBNP levels were associated with higher insulin resistance even after adjustment for BMI, waist circumference and other risk factors (P insulin resistance (P = 0.38; P = 0.01 for comparison with the association of measured levels of NT-proBNP). In older adults, lower NT-proBNP is associated with higher insulin resistance, even after adjustment for traditional risk factors. Because related genetic variants were not associated with insulin resistance, the causal nature of this association will require future study. © 2016 Diabetes UK.

  7. Insulin secretion and insulin resistance in Korean women with gestational diabetes mellitus and impaired glucose tolerance.

    Science.gov (United States)

    Yang, Sae Jeong; Kim, Tae Nyun; Baik, Sei Hyun; Kim, Tae Sun; Lee, Kwan Woo; Nam, Moonsuk; Park, Yong Soo; Woo, Jeong-Teak; Kim, Young Seol; Kim, Sung-Hoon

    2013-05-01

    The aim was to compare the insulin sensitivity and secretion index of pregnant Korean women with normal glucose tolerance (NGT), gestational impaired glucose tolerance (GIGT; only one abnormal value according to the Carpenter and Coustan criteria), and gestational diabetes mellitus (GDM). A cross-sectional study was performed with 1,163 pregnant women with positive (1-hour plasma glucose ≥ 7.2 mmol/L) in a 50-g oral glucose challenge test (OGCT). The 100-g oral glucose tolerance test (OGTT) was used to stratify the participants into three groups: NGT (n = 588), GIGT (n = 294), and GDM (n = 281). The GDM group had higher homeostasis model assessment of insulin resistance and lower insulin sensitivity index (ISOGTT), quantitative insulin sensitivity check index, homeostasis model assessment for estimation of index β-cell secretion (HOMA-B), first and second phase insulin secretion, and insulin secretion-sensitivity index (ISSI) than the NGT group (p ≤ 0.001 for all). Moreover, the GIGT group had lower ISOGTT, HOMA-B, first and second phase insulin secretion, and ISSI than the NGT group (p insulin secretion status than the 3-hour abnormal levels group. Korean women with GDM show impairments of both insulin secretion and insulin sensitivity. In addition, GIGT is associated with both β-cell dysfunction and insulin resistance.

  8. A physiological increase of insulin in the olfactory bulb decreases detection of a learned aversive odor and abolishes food odor-induced sniffing behavior in rats.

    Directory of Open Access Journals (Sweden)

    Pascaline Aimé

    Full Text Available Insulin is involved in multiple regulatory mechanisms, including body weight and food intake, and plays a critical role in metabolic disorders such as obesity and diabetes. An increasing body of evidence indicates that insulin is also involved in the modulation of olfactory function. The olfactory bulb (OB contains the highest level of insulin and insulin receptors (IRs in the brain. However, a role for insulin in odor detection and sniffing behavior remains to be elucidated. Using a behavioral paradigm based on conditioned olfactory aversion (COA to isoamyl-acetate odor, we demonstrated that an intracerebroventricular (ICV injection of 14 mU insulin acutely decreased olfactory detection of fasted rats to the level observed in satiated animals. In addition, whereas fasted animals demonstrated an increase in respiratory frequency upon food odor detection, this effect was absent in fasted animals receiving a 14 mU insulin ICV injection as well as in satiated animals. In parallel, we showed that the OB and plasma insulin levels were increased in satiated rats compared to fasted rats, and that a 14 mU insulin ICV injection elevated the OB insulin level of fasted rats to that of satiated rats. We further quantified insulin receptors (IRs distribution and showed that IRs are preferentially expressed in the caudal and lateral parts of the main OB, with the highest labeling found in the mitral cells, the main OB projection neurons. Together, these data suggest that insulin acts on the OB network to modulate olfactory processing and demonstrate that olfactory function is under the control of signals involved in energy homeostasis regulation and feeding behaviors.

  9. [Metabolic profile in obese patients with obstructive sleep apnea. A comparison between patients with insulin resistance and with insulin sensitivity].

    Science.gov (United States)

    Dumitrache-Rujinski, Stefan; Dinu, Ioana; Călcăianu, George; Erhan, Ionela; Cocieru, Alexandru; Zaharia, Dragoş; Toma, Claudia Lucia; Bogdan, Miron Alexandru

    2014-01-01

    Obstructive sleep apnea syndrome (OSAS) may induce metabolic abnormalities through intermittent hypoxemia and simpathetic activation. It is difficult to demonstrate an independent role of OSAS in the occurrence of metabolic abnormalities, as obesity represents an important risk factor for both OSAS and metabolic abnormalities. to assess the relations between insulin resistance (IR), insulin sensitivity (IS), OSAS severity and nocturnal oxyhaemoglobin levels in obese, nondiabetic patients with daytime sleepiness. We evaluated 99 consecutive, obese, nondiabetic patients (fasting glycemia 5/hour and daytime sleepiness) by an ambulatory six channel cardio-respiratory polygraphy. Hight, weight serum triglycerides (TG), high density lipoprotein-cholesterol (HDL-C) levels were evaluated. Correlations between Apneea Hypopnea Index (AHI), Oxygen Desaturation Index (ODI), average and lowest oxyhaemoglobin saturation (SaO), body mass index (BMI) and insulin resistance or sensitivity were assesed. IR was defined as a TG/ HDL-Cratio > 3, and insulin sensitivity (IS) as a TG/HDL-C ratio obese nondiabetic patients. Preserving insulin sensitivity is more likely when oxyhaemoglobin levels are higher and ODI is lower. Mean lowest nocturnal SaO2 levels seems to be independently involved in the development of insulin resistance as no statistically significant differences were found for BMI between the two groups.

  10. The effect of dietary phytosphingosine on cholesterol levels and insulin sensitivity in subjects with the metabolic syndrome

    NARCIS (Netherlands)

    Snel, M.; Sleddering, M.A.; Pijl, H.; Nieuwenhuizen, W.F.; Frölich, M.; Havekes, L.M.; Romijn, J.A.; Jazet, I.M.

    2010-01-01

    Background: Sphingolipids, like phytosphingosine (PS) are part of cellular membranes of yeasts, vegetables and fruits. Addition of PS to the diet decreases serum cholesterol and free fatty acid (FFA) levels in rodents and improves insulin sensitivity.Objective:To study the effect of dietary

  11. Prediction of the outcome of growth hormone provocative testing in short children by measurement of serum levels of insulin-like growth factor I and insulin-like growth factor binding protein 3

    DEFF Research Database (Denmark)

    Juul, A; Skakkebaek, N E

    1997-01-01

    Serum levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) reflect the secretion of endogenous growth hormone (GH) in healthy children and exhibit little diurnal variation, which makes them potential candidates for screening of GH deficiency (GHD......). We evaluated serum IGF-I and IGFBP-3 levels in relation to the outcome of GH provocative testing in 203 children and adolescents (111 boys and 92 girls) in whom GHD was suspected. A total of 1030 children served as control subjects. In children less than 10 years of age, IGF-I levels were below...... with a normal GH response (specificity 97.9%). Consequently the predictive value of a positive test result in prepubertal children was 88.8% for IGF-I and 90% for IGFBP-3. In children and adolescents between 10 and 20 years of age, IGF-I levels were below the cutoff limit in 34 of 46 children with GHD...

  12. [Differences in dynamics of insulin and insulin-like growth I (IGF-I) receptors internalization in isolated rat hepatocytes].

    Science.gov (United States)

    Kolychev, A P; Ternovskaya, E E; Arsenieva, A V; Shapkina, E V

    2013-01-01

    Insulin and IGF-I are two related peptides performing in the mammalian body functionally different roles of the metabolic and growth hormones, respectively. Internalization of the insulin-receptor complex (IRC) is the most important chain of mechanism of the action of hormone. To elucidate differences in the main stages of internalization of the two related hormones, the internalization dynamics of 125I-insulin and 125I-IGF-I was traced in isolated rat hepatocytes at 37 and 12 degrees C. There were established marked differences in the process of internalization of labeled hormones, which is stimulated by insulin and IGF-I. At 37 degrees C the insulin-stimulated internalization, unlike the process initiated by IGF-I, did not reach the maximal level for 1 h of incubation. However, essential differences in the internalization course of these two related peptide were obvious at the temperature of 12 degrees C. The internalization level of insulin receptors at 12 degrees C decreased by one third in spite of a significant increase of the insulin receptor binding on the hepatocytes plasma membrane. At 12 degrees C a slight decrease of the proportion of intracellular 125I-IGF-I correlated with a decrease in the 125I-IGF-I binding to receptors on the cell membrane. Internalization of IGF-I receptors was not affected by low temperature, as neither its level, nor the rate changed at 12 degrees C. The paradoxical decrease of the insulin-stimulated internalization at low temperature seems to represent a peculiar "inhibition mechanism" of immersion of IRC into the cell, which leads to accumulation of the complexes on the cell surface and possibly to a readjustment of the insulin biological activity. The resistance of internalization of the IGF-I receptor to cold seems to be related to the more ancient origin of this mechanism in the poikilothermal vertebrates.

  13. Insulin signaling is acutely required for long-term memory in Drosophila.

    Science.gov (United States)

    Chambers, Daniel B; Androschuk, Alaura; Rosenfelt, Cory; Langer, Steven; Harding, Mark; Bolduc, Francois V

    2015-01-01

    Memory formation has been shown recently to be dependent on energy status in Drosophila. A well-established energy sensor is the insulin signaling (InS) pathway. Previous studies in various animal models including human have revealed the role of insulin levels in short-term memory but its role in long-term memory remains less clear. We therefore investigated genetically the spatial and temporal role of InS using the olfactory learning and long-term memory model in Drosophila. We found that InS is involved in both learning and memory. InS in the mushroom body is required for learning and long-term memory whereas long-term memory specifically is impaired after InS signaling disruption in the ellipsoid body, where it regulates the level of p70s6k, a downstream target of InS and a marker of protein synthesis. Finally, we show also that InS is acutely required for long-term memory formation in adult flies.

  14. Iontophoresis of monomeric insulin analogues in vitro: effects of insulin charge and skin pretreatment.

    Science.gov (United States)

    Langkjaer, L; Brange, J; Grodsky, G M; Guy, R H

    1998-01-23

    The aim of this study was to investigate the influence of association state and net charge of human insulin analogues on the rate of iontophoretic transport across hairless mouse skin, and the effect of different skin pretreatments on said transport. No insulin flux was observed with anodal delivery probably because of degradation at the Ag/AgCl anode. The flux during cathodal iontophoresis through intact skin was insignificant for human hexameric insulin, and only low and variable fluxes were observed for monomeric insulins. Using stripped skin on the other hand, the fluxes of monomeric insulins with two extra negative charges were 50-100 times higher than that of hexameric human insulin. Introducing three additional charges led to a further 2-3-fold increase in flux. Wiping the skin gently with absolute alcohol prior to iontophoresis resulted in a 1000-fold increase in transdermal transport of insulin relative to that across untreated skin, i.e. to almost the same level as stripping the skin. The alcohol pretreatment reduced the electrical resistance of the skin, presumably by lipid extraction. In conclusion, monomeric insulin analogues with at least two extra negative charges can be iontophoretically delivered across hairless mouse skin, whereas insignificant flux is observed with human, hexameric insulin. Wiping the skin with absolute alcohol prior to iontophoresis gave substantially improved transdermal transport of monomeric insulins resulting in clinically relevant delivery rates for basal treatment.

  15. Association between insulin and executive functioning in alcohol dependence: a pilot study.

    Science.gov (United States)

    Han, Changwoo; Bae, Hwallip; Won, Sung-Doo; Lim, Jaeyoung; Kim, Dai-Jin

    2015-01-01

    Alcohol dependence is a disorder ascribable to multiple factors and leads to cognitive impairment. Given that insulin dysregulation can cause cognitive impairment, patients with alcohol dependence are likely to develop insulin dysregulation such as that in diabetes. The purposes of this study are to identify an association between cognitive functioning and insulin and to investigate insulin as the biomarker of cognitive functioning in alcohol-dependent patients. Serum insulin levels were measured and cognitive functions were assessed in 45 patients with chronic alcoholism. The Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K), a battery of cognitive function tests, was used to assess cognitive functioning. Serum insulin levels were not significantly correlated with most CERAD-K scores, but there was a significant negative correlation with scores on the Trail Making Test B, which is designed to measure executive functioning. Lower serum insulin levels were associated with slower executive functioning responses on the Trail Making Test B, suggesting that executive functioning may be in proportion to serum insulin levels. Thus, in patients with alcohol dependence, insulin level is associated with cognitive functioning. In addition, the present findings suggest that insulin level is a potential biomarker for determining cognitive functioning.

  16. Efficacy of Metformin Versus Insulin in the Management of Pregnancy with Diabetes

    International Nuclear Information System (INIS)

    Waheed, S.; Malik, F.P.

    2013-01-01

    Objective: To compare the efficacy of metformin with insulin in the management of pregnancy with diabetes. Study Design: Randomized clinical trial. Place and Duration of Study: Department of Obstetrics and Gynaecology, Maternal and Child Health Centre (MCH), Pakistan Institute of Medical Sciences, Islamabad, from May 2010 to January 2011. Methodology: A total of 68 pregnant patients with diabetes were included in this study. Patients were randomly divided in to two groups of each 34 patients based on table of random numbers. One was labelled as group-A and other was labelled as group-B. Group-A received insulin and group-B received metformin for the management of diabetes. Results: The mean age was 29.82 A+- 4.58 and 29.35 A+- 4.97 years in groups-A and B respectively. Fasting blood sugar level after 1 month was controlled in 22 (64.7%) patients in group-A and in 27 (79.4%) in group-B (p > 0.05). Fasting blood sugar level at term, remained controlled in 30 (88.2%) patients in group-A and 27 (79.4%) in group-B (p > 0.05). Comparison of random blood sugar levels within normal limits after 1 month in 25 (73.5%) in group-A and in 24 (70.6%) in group-B. At term, random blood sugar level was controlled in 28 (82.4%) and 27 (79.4%) patients in group-A and B, respectively. Comparison of post-treatment HBA1C level depicts that diabetes controlled in 27 (79.4%) patients in group-A while in 28 (82.3%) patients of group-B. The efficacy of metformin and insulin in controlling diabetes was equal in two groups. Conclusion: There was no marked difference in efficacy of metformin and insulin in controlling diabetes in pregnant patients in two groups. (author)

  17. Efficacy of metformin versus insulin in the management of pregnancy with diabetes.

    Science.gov (United States)

    Waheed, Seema; Malik, Farhat Perveen; Mazhar, Syeda Batool

    2013-12-01

    To compare the efficacy of metformin with insulin in the management of pregnancy with diabetes. Randomized clinical trial. Department of Obstetrics and Gynaecology, Maternal and Child Health Centre (MCH), Pakistan Institute of Medical Sciences, Islamabad, from May 2010 to January 2011. A total of 68 pregnant patients with diabetes were included in this study. Patients were randomly divided in to two groups of each 34 patients based on table of random numbers. One was labelled as group-A and other was labelled as group-B. Group-A received insulin and group-B received metformin for the management of diabetes. The mean age was 29.82 ± 4.58 and 29.35 ± 4.97 years in groups-A and B respectively. Fasting blood sugar level after 1 month was controlled in 22 (64.7%) patients in group-A and in 27 (79.4%) in group-B (p > 0.05). Fasting blood sugar level at term, remained controlled in 30 (88.2%) patients in group-A and 27 (79.4%) in group-B (p > 0.05). Comparison of random blood sugar levels within normal limits after 1 month in 25 (73.5%) in group-A and in 24 (70.6%) in group-B. At term, random blood sugar level was controlled in 28 (82.4%) and 27 (79.4%) patients in group-A and B, respectively. Comparison of post-treatment HBA1C level depicts that diabetes controlled in 27 (79.4%) patients in group-A while in 28 (82.3%) patients of group-B. The efficacy of metformin and insulin in controlling diabetes was equal in two groups. There was no marked difference in efficacy of metformin and insulin in controlling diabetes in pregnant patients in two groups.

  18. Identification of metformin poor responders, requiring supplemental insulin, during randomization of metformin versus insulin for the control of gestational diabetes mellitus.

    Science.gov (United States)

    Ashoush, Sherif; El-Said, Mourrad; Fathi, Hisham; Abdelnaby, Mohamed

    2016-06-01

    To evaluate glycemic control among women with gestational diabetes mellitus (GDM) under insulin versus metformin (with or without insulin supplementation), and to identify metformin poor responders requiring supplemental insulin. In Ain Shams University Hospital, mothers with 26-32-week GDM pregnancies, failing diet control, were randomized to receive metformin (n = 47) or insulin (n = 48). The primary outcome was glycemic control. Secondary outcomes included maternal weight, parameters predicting successful metformin monotherapy, neonatal hypoglycemia, and birthweight. Women using metformin (23.4% needing supplemental insulin) gained less weight (P metformin group was related to initial body mass index, HbA1c, oral glucose tolerance test (GTT), and first week mean glucose level. The 1-h glucose level during initial GTT (Hr1-GTT) and the mean fasting glucose level during the first week of therapy (Wk1-mFG) were the two independent parameters associated with requiring supplemental insulin. Women with Hr1-GTT >212 mg/dL and Wk1-mFG >95 mg/dL had a risk ratio of 58.6 (95%CI: 3.68-933.35, P = 0.004) and 11.5 (95%CI: 2.77-47.34,= 0.0008), respectively for needing supplemental insulin during the course of the study compared with women without. Metformin is an effective and safe alternative to insulin in GDM. Women using metformin (± supplemental insulin) had similar glycemic control, less weight gain, and similar rates of side-effects as those on insulin monotherapy. Insulin supplementation to metformin therapy was more likely with elevated Hr1-GTT and Wk1-mFG. © 2016 Japan Society of Obstetrics and Gynecology.

  19. Effect of metformin compared with hypocaloric diet on serum C-reactive protein level and insulin resistance in obese and overweight women with polycystic ovary syndrome.

    Science.gov (United States)

    Esfahanian, Fatemeh; Zamani, Mohammad Mahdi; Heshmat, Ramin; Moini nia, Fatemeh

    2013-04-01

    The aim of the present study was to investigate the efficacy of Metformin compared with a hypocaloric diet on C-reactive protein (CRP) level and markers of insulin resistance in obese and overweight women with polycystic ovary syndrome (PCOS). Forty women with body mass index ≥ 27 and PCOS were randomly allocated to receive either Metformin or hypocaloric diet and were assessed before and after a treatment period of 12 weeks. High-sensitivity CRP (hs-CRP) and markers of insulin resistance (IR), homeostasis model assessment-IR, quantitative insulin-sensitivity check index and fasting glucose to insulin ratio were evaluated in each patient. A total of 10 subjects did not complete the trial (three patients in the Metformin group and seven patients in the diet group) and a total of 30 subjects completed the trial (17 subjects in the Metformin group and 13 subjects in the diet group). Serum concentration of hs-CRP significantly decreased in both the Metformin (5.29 ± 2.50 vs 3.81 ± 1.99, P = 0.008) and diet groups (6.08 ± 2.14 vs 4.27 ± 1.60, P = 0.004). There were no significant differences in mean hs-CRP decrement between the two groups. Decrease in hs-CRP levels was significantly correlated with waist circumference in the diet group (r = 0.8, P hypocaloric diet with 5-10% weight reduction on markers of insulin resistance (homeostasis model assessment-IR, fasting glucose to insulin ratio, quantitative insulin-sensitivity check index) was better than Metformin therapy (P = 0.001). Although weight reduction has equal efficacy with Metformin in decreasing serum hs-CRP levels, it was significantly more effective in improving insulin resistance in obese and overweight PCOS women. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.

  20. Insulin induces a shift in lipid and primary carbon metabolites in a model of fasting-induced insulin resistance

    Science.gov (United States)

    Olmstead, Keedrian I.; La Frano, Michael R.; Fahrmann, Johannes; Grapov, Dmitry; Viscarra, Jose A.; Newman, John W.; Fiehn, Oliver; Crocker, Daniel E.; Filipp, Fabian V.; Ortiz, Rudy M.

    2017-01-01

    Introduction Prolonged fasting in northern elephant seals (NES) is characterized by a reliance on lipid metabolism, conservation of protein, and reduced plasma insulin. During early fasting, glucose infusion previously reduced plasma free fatty acids (FFA); however, during late-fasting, it induced an atypical elevation in FFA despite comparable increases in insulin during both periods suggestive of a dynamic shift in tissue responsiveness to glucose-stimulated insulin secretion. Objective To better assess the contribution of insulin to this fasting-associated shift in substrate metabolism. Methods We compared the responses of plasma metabolites (amino acids (AA), FFA, endocannabinoids (EC), and primary carbon metabolites (PCM)) to an insulin infusion (65 mU/kg) in early- and late-fasted NES pups (n = 5/group). Plasma samples were collected prior to infusion (T0) and at 10, 30, 60, and 120 min post-infusion, and underwent untargeted and targeted metabolomics analyses utilizing a variety of GC-MS and LC-MS technologies. Results In early fasting, the majority (72%) of metabolite trajectories return to baseline levels within 2 h, but not in late fasting indicative of an increase in tissue sensitivity to insulin. In late-fasting, increases in FFA and ketone pools, coupled with decreases in AA and PCM, indicate a shift toward lipolysis, beta-oxidation, ketone metabolism, and decreased protein catabolism. Conversely, insulin increased PCM AUC in late fasting suggesting that gluconeogenic pathways are activated. Insulin also decreased FFA AUC between early and late fasting suggesting that insulin suppresses triglyceride hydrolysis. Conclusion Naturally adapted tolerance to prolonged fasting in these mammals is likely accomplished by suppressing insulin levels and activity, providing novel insight on the evolution of insulin during a condition of temporary, reversible insulin resistance. PMID:28757815

  1. Zinc and homocysteine levels in polycystic ovarian syndrome patients with insulin resistance.

    Science.gov (United States)

    Guler, Ismail; Himmetoglu, Ozdemir; Turp, Ahmet; Erdem, Ahmet; Erdem, Mehmet; Onan, M Anıl; Taskiran, Cagatay; Taslipinar, Mine Yavuz; Guner, Haldun

    2014-06-01

    In this study, our objective was to evaluating the value of serum zinc levels as an etiologic and prognostic marker in patients with polycystic ovarian syndrome. We conducted a prospective study, including 53 women with polycystic ovarian syndrome and 33 healthy controls. We compared serum zinc levels, as well as clinical and metabolic features, of the cases. We also compared serum zinc levels between patients with polycystic ovarian syndrome with insulin resistance. Mean zinc levels were found to be significantly lower in patients with polycystic ovarian syndrome than healthy controls. Multiple logistic regression analysis of significant metabolic variables between polycystic ovarian syndrome and control groups (serum zinc level, body mass index, the ratio of triglyceride/high-density lipoprotein cholesterol, and homocysteine) revealed that zinc level was the most significant variable to predict polycystic ovarian syndrome. Mean serum zinc levels tended to be lower in patients with polycystic ovarian syndrome with impaired glucose tolerance than patients with normal glucose tolerance, but the difference was not statistically significant. In conclusion, zinc deficiency may play a role in the pathogenesis of polycystic ovarian syndrome and may be related with its long-term metabolic complications.

  2. [Insulin resistance--a physiopathological condition with numerous sequelae: non-insulin-dependent diabetes mellitus (NIDDM), android obesity, essential hypertension, dyslipidemia and atherosclerosis].

    Science.gov (United States)

    Pedersen, O

    1992-05-11

    Recent research has demonstrated that reduced insulin-stimulated glucose metabolism in skeletal muscle (insulin resistance) and hyperinsulinism are common features in widespread diseases such as essential hypertension, android obesity, non-insulin dependent diabetes mellitus, dyslipidemia (in the form of raised serum triglyceride and reduced serum high-density lipoprotein (HDL) cholesterol) and arteriosclerosis. Simultaneously, investigations in a comprehensive group of healthy middle-aged men have revealed insulin resistance in one fourth. On the basis of these observations, a working hypothesis is suggested which postulates that genetic abnormalities in one or more of the candidate genes in the modes of action of insulin occur in a great proportion of the population. These may result in insulin resistance (primary genetic insulin resistance). Primary insulin resistance may be potentiated by a series of circumstances such as ageing, high-fat diet, lack of physical activity, hormonal and metabolic abnormalities or drugs (secondary insulin resistance). As a consequence of the reduced effect of insulin on muscle tissue, compensatory hyperinsulinism develops. Depending on the remaining vulnerability of the individual the hyperinsulinism is presumed to result in development of one or more phenotypes. For example if the beta-cells of the pancreas are unable to secrete sufficient insulin to compensate the insulin resistance on account of genetic defects, glucose intolerance will develop. In a similar manner, hyperinsulinism in insulin-resistant individuals who are predisposed to essential hypertension is presumed to reveal genetic defects in the blood pressure regulating mechanisms and thus contribute to development of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. The role of polycarbonate monomer bisphenol-A in insulin resistance.

    Science.gov (United States)

    Pjanic, Milos

    2017-01-01

    what extent BPA might contribute to the development of diabetes in the modern societies still remains unknown. In this review, I discuss the chemical properties of BPA and the sources of BPA contamination found in the environment and in human tissues. I provide an overview of mechanisms for the proposed role of bisphenol A in insulin resistance and diabetes, as well as other related diseases, such as cardiovascular diseases. I describe the transmission of BPA effects to the offspring and postulate that gender related differences might originate from differences in liver enzyme levels, such as UDP-glucuronosyltransferase, which is involved in BPA processing and its elimination from the organism. I discuss the molecular mechanisms of BPA action through nuclear and membrane-bound ER receptors, non-monotonic dose response, epigenetic modifications of the DNA and propose that chronic exposure to weak binders, such as BPA, may mimic the effects of strong binders, such as estrogens.

  4. Glutamate Cysteine Ligase—Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage

    KAUST Repository

    Lavoie, Suzie

    2016-04-21

    Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.

  5. Glutamate Cysteine Ligase—Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage

    KAUST Repository

    Lavoie, Suzie; Steullet, Pascal; Kulak, Anita; Preitner, Frederic; Do, Kim Q.; Magistretti, Pierre J.

    2016-01-01

    Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.

  6. Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats.

    Science.gov (United States)

    Yamazaki, Ricardo K; Brito, Gleisson A P; Coelho, Isabela; Pequitto, Danielle C T; Yamaguchi, Adriana A; Borghetti, Gina; Schiessel, Dalton Luiz; Kryczyk, Marcelo; Machado, Juliano; Rocha, Ricelli E R; Aikawa, Julia; Iagher, Fabiola; Naliwaiko, Katya; Tanhoffer, Ricardo A; Nunes, Everson A; Fernandes, Luiz Claudio

    2011-04-28

    Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Monosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish oil-treated normal weight group (FO), obese control group (Ob), coconut fat-treated obese group (ObCO) and fish oil-treated obese group (ObFO). Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day) for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. Obese animals (Ob) presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt) showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO) similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30%) and triacylglycerol (TG; 33%) compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. Low dose of fish oil supplementation (1 g/kg/day) was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.

  7. Serum leptin and insulin tests in obesity

    International Nuclear Information System (INIS)

    Yang Yin; Jiang Xiaojin; Leng Xiumei

    2001-01-01

    Objective: To study the clinical significance and the relations of leptin and insulin on obesity group. Methods: Leptin and insulin were tested with radioimmunoassay (RIA) in pre-obesity group and obesity group respectively. Results: Serum leptin and insulin levels were significantly elevated in obesity group compare with the controls (P<0.01). Conclusion: Changing with insulin, the elevation of leptin in obesity group has been identified as an important agent of diabetes mellitus (DM)

  8. The effect of dietary phytosphingosine on cholesterol levels and insulin sensitivity in subjects with the metabolic syndrome

    NARCIS (Netherlands)

    Snel, M.; Sleddering, M. A.; Pijl, H.; Nieuwenhuizen, W. F.; Frölich, M.; Havekes, L. M.; Romijn, J. A.; Jazet, I. M.

    2010-01-01

    Sphingolipids, like phytosphingosine (PS) are part of cellular membranes of yeasts, vegetables and fruits. Addition of PS to the diet decreases serum cholesterol and free fatty acid (FFA) levels in rodents and improves insulin sensitivity. To study the effect of dietary supplementation with PS on

  9. Treatment of spontaneously hypertensive rats with rosiglitazone and/or enalapril restores balance between vasodilator and vasoconstrictor actions of insulin with simultaneous improvement in hypertension and insulin resistance.

    Science.gov (United States)

    Potenza, Maria A; Marasciulo, Flora L; Tarquinio, Mariela; Quon, Michael J; Montagnani, Monica

    2006-12-01

    Spontaneously hypertensive rats (SHRs) exhibit endothelial dysfunction and insulin resistance. Reciprocal relationships between endothelial dysfunction and insulin resistance may contribute to hypertension by causing imbalanced regulation of endothelial-derived vasodilators (e.g., nitric oxide) and vasoconstrictors (e.g., endothelin-1 [ET-1]). Treatment of SHRs with rosiglitazone (insulin sensitizer) and/or enalapril (ACE inhibitor) may simultaneously improve hypertension, insulin resistance, and endothelial dysfunction by rebalancing insulin-stimulated production of vasoactive mediators. When compared with WKY control rats, 12-week-old vehicle-treated SHRs were hypertensive, overweight, and insulin resistant, with elevated fasting levels of insulin and ET-1 and reduced serum adiponectin levels. In mesenteric vascular beds (MVBs) isolated from vehicle-treated SHRs and preconstricted with norepinephrine (NE) ex vivo, vasodilator responses to insulin were significantly impaired, whereas the ability of insulin to oppose vasoconstrictor actions of NE was absent (versus WKY controls). Three-week treatment of SHRs with rosiglitazone and/or enalapril significantly reduced blood pressure, insulin resistance, fasting insulin, and ET-1 levels and increased adiponectin levels to values comparable with those observed in vehicle-treated WKY controls. By restoring phosphatidylinositol 3-kinase-dependent effects, rosiglitazone and/or enalapril therapy of SHRs also significantly improved vasodilator responses to insulin in MVB preconstricted with NE ex vivo. Taken together, our data provide strong support for the existence of reciprocal relationships between endothelial dysfunction and insulin resistance that may be relevant for developing novel therapeutic strategies for the metabolic syndrome.

  10. Impact of diisobutyl phthalate and other PPAR agonists on steroidogenesis and plasma insulin and leptin levels in fetal rats

    International Nuclear Information System (INIS)

    Boberg, Julie; Metzdorff, Stine; Wortziger, Rasmus; Axelstad, Marta; Brokken, Leon; Vinggaard, Anne Marie; Dalgaard, Majken; Nellemann, Christine

    2008-01-01

    Endocrine disrupting chemicals can induce malformations and impairment of reproductive function in experimental animals and may have similar effects in humans. Recently, the environmental obesogen hypothesis was proposed, suggesting that environmental chemicals contribute to the development of obesity and insulin resistance. These effects could be related to chemical interaction with nuclear receptors such as the peroxisome proliferator activated receptors (PPARs). As several testosterone-reducing drugs are PPAR activators, we aimed to examine whether four PPAR agonists were able to affect fetal testosterone production and masculinization of rats. Additionally, we wished to examine whether these chemicals affected fetal plasma levels of insulin and leptin, which play important roles in the developmental programming of the metabolic system. Pregnant Wistar rats were exposed from gestation day (GD) 7-21 to diisobutyl phthalate (DiBP), butylparaben, perfluorooctanoate, or rosiglitazone (600, 100, 20, or 1 mg/kg bw/day, respectively). Endocrine endpoints were studied in offspring at GD 19 or 21. DiBP, butylparaben and rosiglitazone reduced plasma leptin levels in male and female offspring. DiBP and rosiglitazone additionally reduced fetal plasma insulin levels. In males, DiBP reduced anogenital distance, testosterone production and testicular expression of Insl-3 and genes related to steroidogenesis. PPARα mRNA levels were reduced by DiBP at GD 19 in testis and liver. In females, DiBP increased anogenital distance and increased ovarian aromatase mRNA levels. This study reveals new targets for phthalates and parabens in fetal male and female rats and contributes to the increasing concern about adverse effects of human exposure to these compounds

  11. Function of insulin in snail brain in associative learning.

    Science.gov (United States)

    Kojima, S; Sunada, H; Mita, K; Sakakibara, M; Lukowiak, K; Ito, E

    2015-10-01

    Insulin is well known as a hormone regulating glucose homeostasis across phyla. Although there are insulin-independent mechanisms for glucose uptake in the mammalian brain, which had contributed to a perception of the brain as an insulin-insensitive organ for decades, the finding of insulin and its receptors in the brain revolutionized the concept of insulin signaling in the brain. However, insulin's role in brain functions, such as cognition, attention, and memory, remains unknown. Studies using invertebrates with their open blood-vascular system have the promise of promoting a better understanding of the role played by insulin in mediating/modulating cognitive functions. In this review, the relationship between insulin and its impact on long-term memory (LTM) is discussed particularly in snails. The pond snail Lymnaea stagnalis has the ability to undergo conditioned taste aversion (CTA), that is, it associatively learns and forms LTM not to respond with a feeding response to a food that normally elicits a robust feeding response. We show that molluscan insulin-related peptides are up-regulated in snails exhibiting CTA-LTM and play a key role in the causal neural basis of CTA-LTM. We also survey the relevant literature of the roles played by insulin in learning and memory in other phyla.

  12. Insulin and Glucagon

    DEFF Research Database (Denmark)

    Holst, Jens Juul; Holland, William; Gromada, Jesper

    2017-01-01

    In August 2016, several leaders in glucagon biology gathered for the European Association for the Study of Diabetes Hagedorn Workshop in Oxford, England. A key point of discussion focused on the need for basal insulin to allow for the therapeutic benefit of glucagon blockade in the treatment...... of the discussion as a consensus was reached. Agents that antagonize glucagon may be of great benefit for the treatment of diabetes; however, sufficient levels of basal insulin are required for their therapeutic efficacy....

  13. Peroxisome Proliferator-Activated Receptors and Hepatitis C Virus-Induced Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Francesco Negro

    2009-01-01

    Full Text Available Insulin resistance and type 2 diabetes are associated with hepatitis C virus infection. A wealth of clinical and experimental data suggests that the virus is directly interfering with the insulin signalling in hepatocytes. In the case of at least one viral genotype (the type 3a, insulin resistance seems to be directly mediated by the downregulation of the peroxisome proliferator-activated receptor γ. Whether and how this interaction may be manipulated pharmacologically, in order to improve the responsiveness to antivirals of insulin resistant chronic hepatitis C, patients remain to be fully explored.

  14. Association Between Insulin Resistance and Bone Structure in Nondiabetic Postmenopausal Women

    DEFF Research Database (Denmark)

    Shanbhogue, Vikram V; Finkelstein, Joel S; Bouxsein, Mary L

    2016-01-01

    computed tomography was used to assess bone density and microstructure at the distal radius and tibia. Fasting insulin and glucose was measured and insulin resistance was estimated using homeostasis model assessment of insulin resistance (HOMA-IR) with higher values indicating greater insulin resistance....... RESULTS: There was a negative association between HOMA-IR and bone size and a positive association between HOMA-IR and total vBMD, trabecular vBMD, trabecular thickness and cortical thickness at the radius and tibia. These relationships remained even after adjusting for body weight and other potential...

  15. A clinical study on insulin receptors of mononuclear cells in diabetes

    International Nuclear Information System (INIS)

    Dalimunthe, D.

    1980-01-01

    125 I-insulin binding activity to mononuclear cells was studied in 75 noninsulin-dependent diabetic subjects and 31 normal subjects and the following results were obtained. 1. 125 I-insulin binding is directly proportional to the mononuclear cell concentrations. There is a linear increase of specific 125 I-insulin binding. 2. The binding of 125 I-insulin to mononuclear cells is displaced by the increasing concentration of native insulin. 3. The 125 I-insulin degradation in the incubation medium after incubation of mononuclear cells for 24 hours at 4 0 C was almost 5% in this study. 4. The insulin binding activity in diabetic subjects was lower than that in normal subjects (P < 0.001) without any significant difference in affinity constant. 5. The relationship of binding activity to age of diabetics (r = 0.06, N.S), relative body weitht (r = 0.06, N.S) and duration of diabetes from onset was not significant. 6. In untreated noninsulin-dependent diabetics the insulin binding activity was inversely correlated to fasting blood glucose level (r = 0.78, P < 0.001) and slightly inversely correlated to serum insulin level (r = 0.47, P < 0.01). A slight inverse correlation was also observed in serum triglyceride level (r = 0.53, P < 0.01) and in total cholesterol level (r = 0.29, P < 0.05). 7. No significant difference between the binding activity was observed by grade of diabetic retinopathy. 8. After treatment with diet and/or sulfonylurea, the diabetics exhibited a significant increase in insulin binding activity (P < 0.005) but no significant difference in plasma insulin level, body weight and plasma lipid levels was observed. (author)

  16. Nutrient sensing and insulin signaling in neuropeptide-expressing immortalized, hypothalamic neurons: A cellular model of insulin resistance.

    Science.gov (United States)

    Fick, Laura J; Belsham, Denise D

    2010-08-15

    Obesity and type 2 diabetes mellitus represent a significant global health crisis. These two interrelated diseases are typified by perturbed insulin signaling in the hypothalamus. Using novel hypothalamic cell lines, we have begun to elucidate the molecular and intracellular mechanisms involved in the hypothalamic control of energy homeostasis and insulin resistance. In this review, we present evidence of insulin and glucose signaling pathways that lead to changes in neuropeptide gene expression. We have identified some of the molecular mechanisms involved in the control of de novo hypothalamic insulin mRNA expression. And finally, we have defined key mechanisms involved in the etiology of cellular insulin resistance in hypothalamic neurons that may play a fundamental role in cases of high levels of insulin or saturated fatty acids, often linked to the exacerbation of obesity and diabetes.

  17. C-Peptide, Baseline and Postprandial Insulin Resistance after a Carbohydrate-Rich Test Meal - Evidence for an Increased Insulin Clearance in PCOS Patients?

    Science.gov (United States)

    Stassek, J; Erdmann, J; Ohnolz, F; Berg, F D; Kiechle, M; Seifert-Klauss, V

    2017-01-01

    Introduction Known characteristics of patients with PCOS include infertility, menstrual disorders, hirsutism and also often insulin resistance. These symptoms increase with increasing body weight. In the LIPCOS study ( L ifestyle I ntervention for Patients with Polycystic Ovary Syndrome [ PCOS ]) long-term changes of the PCOS in dependence on pregnancy and parenthood were systematically assessed. In the framework of the LIPCOS study, PCOS patients were given a standardised carbohydrate-rich test meal in order to examine glucose homeostasis and insulin secretion. The results were compared with those of a eumenorrhoeic control group who all had corresponding BMI values and corresponding ages. Methods and Patients 41 PCOS patients (without diabetes) and 68 controls received a standardised carbohydrate-rich test meal (260 kcal, 62 % carbohydrates, 32 % fat, 6 % proteins) in order to generate a submaximal insulin and glucose stimulation. The values were determined at baseline and postprandial after 60, 120 and 180 minutes. In addition, the corresponding C-peptide levels were recorded. Results In the PCOS patients (n = 41), the insulin secretion test after a standardised test meal showed almost identical baseline and postprandial insulin levels when compared with those of the age- and BMI-matched eumenorrhoeic controls (n = 68). In the PCOS patients, the baseline and postprandial glucose levels were significantly elevated (92.88 ± 10.28 [PCOS] vs. 85.07 ± 9.42 mg/dL [controls]; p PCOS patients formally exhibit a higher fasting insulin resistance than controls. In spite of the higher stimulated C-peptide levels, the insulin levels did not increase more strongly with increasing glucose levels than in controls which may be indicative of a higher insulin clearance in PCOS patients.

  18. D-sorbose inhibits disaccharidase activity and demonstrates suppressive action on postprandial blood levels of glucose and insulin in the rat.

    Science.gov (United States)

    Oku, Tsuneyuki; Murata-Takenoshita, Yoko; Yamazaki, Yuko; Shimura, Fumio; Nakamura, Sadako

    2014-11-01

    In an attempt to develop D-sorbose as a new sweetener that could help in preventing lifestyle-related diseases, we investigated the inhibitory effect of D-sorbose on disaccharidase activity, using the brush border membrane vesicles of rat small intestines. The inhibitory effect was compared with that of L-sorbose and other rare sugars, and the small intestinal disaccharidases in rats was compared with that of humans as well. In humans and the small intestines of rats, d-sorbose strongly inhibited sucrase activity and weakly inhibited maltase activity. Inhibition by D-sorbose of sucrase activity was similar to that of L-arabinose, and the K(i) of D-sorbose was 7.5 mM. Inhibition by D-sorbose was very strong in comparison with that of L-sorbose (K(i), 60.8 mM), whereas inhibition of d-tagatose was between that of D-sorbose and L-sorbose. The inhibitory mode of D-sorbose for sucrose and maltase was uncompetitive, and that of L-sorbose was competitive. To determine a suppressive effect on postprandial blood levels of glucose and insulin via inhibition of sucrase activity, sucrose solution with or without D-sorbose was administered to rats. Increments in the blood levels of glucose and insulin were suppressed significantly after administration of sucrose solution with D-sorbose to rats, in comparison to administration of sucrose solution without D-sorbose. In contrast, the suppressive effect of L-sorbose on postprandial blood levels of glucose and insulin was very weak. These results suggest that D-sorbose may have an inhibitory effect on disaccharidase activity and could be used as a sweetener to suppress the postprandial elevation of blood levels of glucose and insulin. The use of D-sorbose as a sweetener may contribute to the prevention of lifestyle-related diseases, such as type 2 diabetes mellitus. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Inverse Relationship of the CMKLR1 Relative Expression and Chemerin Serum Levels in Obesity with Dysmetabolic Phenotype and Insulin Resistance

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    Fernanda-Isadora Corona-Meraz

    2016-01-01

    Full Text Available Background. In obesity there is a subclinical chronic low-grade inflammatory response where insulin resistance (IR may develop. Chemerin is secreted in white adipose tissue and promotes low-grade inflammatory process, where it expressed CMKLR1 receptor. The role of chemerin and CMKLR1 in inflammatory process secondary to obesity is not defined yet. Methods. Cross-sectional study with 134 individuals classified as with and without obesity by body mass index (BMI and IR. Body fat storage measurements and metabolic and inflammatory markers were measured by routine methods. Soluble chemerin and basal levels of insulin by ELISA and relative expression of CMKLR1 were evaluated with qPCR and 2-ΔΔCT method. Results. Differences (P<0.05 were observed between obesity and lean individuals in body fat storage measurements and metabolic-inflammatory markers. Both CMKLR1 expression and chemerin levels were increased in obesity without IR. Soluble chemerin levels correlate with adiposity and metabolic markers (r=8.8% to 38.5%, P<0.05. Conclusion. The increment of CMKLR1 expression was associated with insulin production. Increased serum levels of chemerin in obesity were observed, favoring a dysmetabolic response. The results observed in this study suggest that both chemerin and CMKLR1 have opposite expression in the context of low-grade inflammatory response manifested in the development of IR.

  20. Liraglutide increases FGF-21 activity and insulin sensitivity in high fat diet and adiponectin knockdown induced insulin resistance.

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    Mengliu Yang

    Full Text Available BACKGROUND: Liraglutide is a glucagon-like peptide-1 analogue that stimulates insulin secretion and improves β-cell function. However, it is not clear whether liraglutide achieves its glucose lowering effect only by its known effects or whether other as yet unknown mechanisms are involved. The aim of this study was to examine the effects of liraglutide on Fibroblast growth factor-21 (FGF-21 activity in High-fat diet (HFD fed ApoE(-/- mice with adiponectin (Acrp30 knockdown. METHOD: HFD-fed ApoE(-/- mice were treated with adenovirus vectors expressing shAcrp30 to produce insulin resistance. Hyperinsulinemic-euglycemic clamp studies were performed to evaluate insulin sensitivity of the mouse model. QRT-PCR and Western blot were used to measure the mRNA and protein expression of the target genes. RESULTS: The combination of HFD, ApoE deficiency, and hypoadiponectinemia resulted in an additive effect on insulin resistance. FGF-21 mRNA expressions in both liver and adipose tissues were significantly increased while FGF-21 receptor 1 (FGFR-1 and β-Klotho mRNA levels in adipose tissue, as well as FGFR-1-3 and β-Klotho mRNA levels in liver were significantly decreased in this model. Liraglutide treatment markedly improved insulin resistance and increased FGF-21 expression in liver and FGFR-3 in adipose tissue, restored β-Klotho mRNA expression in adipose tissue as well as FGFR-1-3, β-Klotho levels and phosphorylation of FGFR1 up to the levels observed in control mice in liver. Liraglutide treatment also further increased FGF-21 proteins in liver and plasma. In addition, as shown by hyperinsulinemic-euglycemic clamp, liraglutide treatment also markedly improved glucose metabolism and insulin sensitivity in these animals. CONCLUSION: These findings demonstrate an additive effect of HFD, ApoE deficiency, and adiponectin knockdown on insulin resistance and unveil that the regulation of glucose metabolism and insulin sensitivity by liraglutide may be

  1. [Insulin-sensitizing agents: metformin and thiazolidinedione derivatives].

    Science.gov (United States)

    Satoh, Jo

    2003-07-01

    Both metformin and thiazolidinedione derivatives(TZDs) improve insulin resistance, a major pathogenesis of type 2 diabetes, and decrease blood glucose levels without stimulating insulin secretion. Metformin inhibits glucose output from the liver, while TZDs increase glucose utilization in the peripheral tissues. In addition, there has been indicated that these agents ameliorate metabolic syndrome beyond glucose-level lowering. Molecular targets of these agents have recently been revealed; AMP-activated protein kinase (AMPK) for metformin and adiponectin, while PPAR gamma for TZDs which induce gene expression of adipocyte glycerol kinase and adiponectin. Insulin-sensitizing agents are clinically useful for obese diabetic patients with insulin resistance. However, periodical examinations are necessary to avoid serious adverse effects such as lactic acidosis, although rare, by metformin and liver injury by TZDs.

  2. Molecular Mechanisms of Insulin Resistance Development

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    Vsevolod Arsen'evich Tkachuk

    2014-05-01

    Full Text Available Insulin resistance (IR is a phenomenon associated with an impaired ability of insulin to stimulate glucose uptake by target cells and to reduce the blood glucose level. A response increase in insulin secretion by the pancreas and hyperinsulinemia are compensatory reactions of the body. The development of IR leads to the inability of target cells to respond to insulin that results in developing type 2 diabetes mellitus (T2DM and metabolic syndrome. For this reason, the metabolic syndrome is defined in practice as a combination of IR with one or more pathologies such as T2DM, arterial hypertension, dyslipidemia, abdominal obesity, non-alcoholic fatty liver disease, and some others. However, a combination of high blood glucose and insulin levels always serves as its physiological criterion.IR should be considered as a systemic failure of the endocrine regulation in the body. Physiological causes of IR are diverse. The main ones are nutritional overload and accumulation of certain lipids and their metabolites in cells, low physical activity, chronic inflammation and stress of various nature, including oxidative and endoplasmic reticulum stress (impairment of damaged protein degradation in the cell. Recent studies have demonstrated that these physiological mechanisms likely act through a single intracellular scenario. This is the impairment of signal transduction from the insulin receptor to its targets via the negative feedback mechanism in intracellular insulin-dependent signaling cascades.This review describes the physiological and intracellular mechanisms of insulin action and focuses on their abnormalities upon IR development. Finally, feasible trends in early molecular diagnosis and therapy of IR are discussed.

  3. Adiposity, insulin and lipid metabolism in post-menopausal women.

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    Lovegrove, J A; Silva, K D R R; Wright, J W; Williams, C M

    2002-04-01

    To investigate relationships between body fat and its distribution and carbohydrate and lipid tolerance using statistical comparisons in post-menopausal women. Sequential meal, postprandial study (600 min) which included a mixed standard breakfast (30 g fat) and lunch (44 g fat) given at 0 and 270 min, respectively, after an overnight fast. Twenty-eight post-menopausal women with a diverse range of body weight (body mass index (BMI), mean 27.2, range 20.5-38.8 kg/m2) and abdominal fat deposition (waist, mean 86.4, range 63.5-124.0 cm). Women with BMI 37 kg/m2, age > 80 y and taking hormone replacement therapy (HRT) were excluded. Anthropometric measurements were performed to assess total and regional fat deposits. The concentrations of plasma total cholesterol, high density lipoprotein (HDL) cholesterol, triacylglycerol (TAG), glucose, insulin (ins), non-esterified fatty acids (NEFA) and apolipoprotein (apo) B-48 were analysed in plasma collected at baseline (fasted state) and at 13 postprandial time points for a 600 min period. Insulin concentrations in the fasted and fed state were significantly correlated with all measures of adiposity (BMI, waist, waist-hip ratio (W/H), waist-height ratio (W/Ht) and sum of skinfold thickness (SSk)). After controlling for BMI, waist remained significantly and positively associated with fasted insulin (r=0.559) with waist contributing 53% to the variability after multiple regression analysis. After controlling for waist, BMI remained significantly correlated with postprandial (IAUC) insulin (r=0.535) contributing 66% of the variability of this measurement. No association was found between any measures of adiposity and glucose concentrations, although insulin concentration in relation to glucose concentration (glucose-insulin ratio) was significantly negatively correlated with all measures of adiposity. A significant positive correlation was found between fasted TAG and BMI (r=0.416), waist (r=0.393) and Ssk (r=0.457) and

  4. A combination of l-arabinose and chromium lowers circulating glucose and insulin levels after an acute oral sucrose challenge

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    Perricone Nicholas V

    2011-05-01

    Full Text Available Abstract Background A growing body of research suggests that elevated circulating levels of glucose and insulin accelerate risk factors for a wide range of disorders. Low-risk interventions that could suppress glucose without raising insulin levels could offer significant long-term health benefits. Methods To address this issue, we conducted two sequential studies, the first with two phases. In the first phase of Study 1, baseline fasting blood glucose was measured in 20 subjects who consumed 70 grams of sucrose in water and subsequently completed capillary glucose measurements at 30, 45, 60 and 90 minutes (Control. On day-2 the same procedure was followed, but with subjects simultaneously consuming a novel formula containing l-arabinose and a trivalent patented food source of chromium (LA-Cr (Treatment. The presence or absence of the LA-Cr was blinded to the subjects and testing technician. Comparisons of changes from baseline were made between Control and Treatment periods. In the second phase of Study 1, 10 subjects selected from the original 20 competed baseline measures of body composition (DXA, a 43-blood chemistry panel and a Quality of Life Inventory. These subjects subsequently took LA-Cr daily for 4 weeks completing daily tracking forms and repeating the baseline capillary tests at the end of each of the four weeks. In Study 2, the same procedures used in the first phase were repeated for 50 subjects, but with added circulating insulin measurements at 30 and 60 minutes from baseline. Results In both studies, as compared to Control, the Treatment group had significantly lower glucose responses for all four testing times (AUC = P P = Conclusions As compared to a placebo control, consumption of a LA-Cr formula after a 70-gram sucrose challenge was effective in safely lowering both circulating glucose and insulin levels. Trial Registration Clinical Trials.gov, NCT0110743

  5. Insulin and insulin signaling play a critical role in fat induction of insulin resistance in mouse

    Science.gov (United States)

    Ning, Jie; Hong, Tao; Yang, Xuefeng; Mei, Shuang; Liu, Zhenqi; Liu, Hui-Yu

    2011-01-01

    The primary player that induces insulin resistance has not been established. Here, we studied whether or not fat can cause insulin resistance in the presence of insulin deficiency. Our results showed that high-fat diet (HFD) induced insulin resistance in C57BL/6 (B6) mice. The HFD-induced insulin resistance was prevented largely by the streptozotocin (STZ)-induced moderate insulin deficiency. The STZ-induced insulin deficiency prevented the HFD-induced ectopic fat accumulation and oxidative stress in liver and gastrocnemius. The STZ-induced insulin deficiency prevented the HFD- or insulin-induced increase in hepatic expression of long-chain acyl-CoA synthetases (ACSL), which are necessary for fatty acid activation. HFD increased mitochondrial contents of long-chain acyl-CoAs, whereas it decreased mitochondrial ADP/ATP ratio, and these HFD-induced changes were prevented by the STZ-induced insulin deficiency. In cultured hepatocytes, we observed that expressions of ACSL1 and -5 were stimulated by insulin signaling. Results in cultured cells also showed that blunting insulin signaling by the PI3K inhibitor LY-294002 prevented fat accumulation, oxidative stress, and insulin resistance induced by the prolonged exposure to either insulin or oleate plus sera that normally contain insulin. Finally, knockdown of the insulin receptor prevented the oxidative stress and insulin resistance induced by the prolonged exposure to insulin or oleate plus sera. Together, our results show that insulin and insulin signaling are required for fat induction of insulin resistance in mice and cultured mouse hepatocytes. PMID:21586696

  6. Retroendocytosis of insulin in rat adipocytes

    International Nuclear Information System (INIS)

    Levy, J.R.; Olefsky, J.M.

    1986-01-01

    A variety of ligands internalized by receptor-mediated endocytosis follow a short circuit pathway that does not lead to degradation but results in rapid exocytosis of intact ligand, a process termed retroendocytosis. We studied the time course of [ 125 I]iodoinsulin processing and retroendocytosis after internalization in isolated rat adipocytes. After steady state binding and internalization, surface receptor-bound insulin was removed by exposing cells to a low pH at low temperatures. The cells containing internalized [ 125 I]iodoinsulin were reincubated in fresh medium; subsequently, the radioactivity remaining within the cells and released into the medium were analyzed at various times by trichloroacetic acid (TCA) precipitation, Sephadex G-50 gel filtration, and reverse phase HPLC. Cell-associated radioactivity progressively decreased after reincubation in 37 C buffer, with 50% released in 9 min and 85% by 45 min. In the media, TCA-precipitable material appeared quickly, with a t1/2 of 2 min, and plateaued by 10 min. TCA-soluble material was released continually throughout the 45-min period. The release of both TCA-precipitable and TCA-soluble material was temperature and energy dependent. Sephadex G-50 chromatography demonstrated the loss of insulin from the intracellular pool and its appearance in the medium with a time course similar to that of TCA-precipitable material. Reverse phase HPLC demonstrated that the intracellular and medium radioactivity eluting in peak II (insulin peak) on Sephadex G-50 was composed of both intact insulin and intermediates. After the internalization of insulin, rat adipocytes release not only small mol wt degradation products of insulin, but also insulin intermediates and intact insulin. The rate of retroendocytosis reported here is almost identical to the rate of insulin receptor recycling in rat adipocytes

  7. Studies on insulin secretion and insulin resistance in non-insulin-dependent diabetes in young Indians

    International Nuclear Information System (INIS)

    Naidoo, C.

    1986-01-01

    Patients with Non-insulin-dependent diabetes mellitus (NIDDM) have defects in insulin secretion and insulin action. In the discrete genetic syndrome of NIDDY (non-insulin-dependent diabetes in the young), the situation is less clear and these aspects is the subject of this thesis. This study included Indian pasients with three generation transmission of NIDDM via one parent. The insulin and C-peptide responses to oral and intravenous glucose in patients with NIDDY were studied. The insulin and glucose responses to non-glucose secretogogues glucagon, tolbutamide and arginine, in NIDDY were also investigated. The following aspects with regard to insulin resistance in NIDDY were examined: glucose and free fatty acid response to intravenous insulin administration, insulin binding to circulating erythrocytes and monocytes, 125 I-insulin binding to the solubilized erythrocyte membrane receptor and 125 I-insulin binding to fibroblasts in culture

  8. Studies on insulin secretion and insulin resistance in non-insulin-dependent diabetes in young Indians

    Energy Technology Data Exchange (ETDEWEB)

    Naidoo, C

    1986-01-01

    Patients with Non-insulin-dependent diabetes mellitus (NIDDM) have defects in insulin secretion and insulin action. In the discrete genetic syndrome of NIDDY (non-insulin-dependent diabetes in the young), the situation is less clear and these aspects is the subject of this thesis. This study included Indian pasients with three generation transmission of NIDDM via one parent. The insulin and C-peptide responses to oral and intravenous glucose in patients with NIDDY were studied. The insulin and glucose responses to non-glucose secretogogues glucagon, tolbutamide and arginine, in NIDDY were also investigated. The following aspects with regard to insulin resistance in NIDDY were examined: glucose and free fatty acid response to intravenous insulin administration, insulin binding to circulating erythrocytes and monocytes, /sup 125/I-insulin binding to the solubilized erythrocyte membrane receptor and /sup 125/I-insulin binding to fibroblasts in culture.

  9. Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats

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    Iagher Fabiola

    2011-04-01

    Full Text Available Abstract Background Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Methods Monosodium glutamate (MSG (4 mg/g body weight was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C, coconut fat-treated normal weight group (CO, fish oil-treated normal weight group (FO, obese control group (Ob, coconut fat-treated obese group (ObCO and fish oil-treated obese group (ObFO. Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. Results Obese animals (Ob presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30% and triacylglycerol (TG; 33% compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. Conclusions Low dose of fish oil supplementation (1 g/kg/day was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.

  10. The relationship between dietary habits, blood glucose and insulin levels among people without cardiovascular disease and type 2 diabetes; the ATTICA study.

    Science.gov (United States)

    Panagiotakos, Demosthenes B; Tzima, Natalia; Pitsavos, Christos; Chrysohoou, Christina; Papakonstantinou, Emilia; Zampelas, Antonis; Stefanadis, Christodoulos

    2005-01-01

    Diet has long been associated with a risk of insulin resistance and poor glycemic control. We sought to investigate the association between food groups and indices of glycemic control in adults without type 2 diabetes and cardiovascular disease. During 2001 - 2002 we randomly enrolled 1514 men (18-87 years old) and 1528 women (18-89 years old) without evidence of cardiovascular disease from the Attica area of Greece. Of them, 118 men and 92 women were excluded from the present analysis due to a history of diabetes mellitus (type 2). Fasting blood glucose and insulin levels were measured, while dietary habits were evaluated through a semi-quantitative food frequency questionnaire. Red meat consumption was positively associated with hyperglycemia (p = 0.04), hyperinsulinemia (p = 0.04), and HOMA levels (p = 0.03), even after adjusting for BMI and various other potential confounders. The intake of fruits, vegetables, legumes, yogurt and other dairy products was not associated with levels of glycemic control indices. A higher consumption of red meat and its products may aggravate hyperinsulinemia and insulin resistance in non-diabetic people.

  11. Central insulin-like growth factor-1 (IGF-1) restores whole-body insulin action in a model of age-related insulin resistance and IGF-1 decline.

    Science.gov (United States)

    Huffman, Derek M; Farias Quipildor, Gabriela; Mao, Kai; Zhang, Xueying; Wan, Junxiang; Apontes, Pasha; Cohen, Pinchas; Barzilai, Nir

    2016-02-01

    Low insulin-like growth factor-1 (IGF-1) signaling is associated with improved longevity, but is paradoxically linked with several age-related diseases in humans. Insulin-like growth factor-1 has proven to be particularly beneficial to the brain, where it confers protection against features of neuronal and cognitive decline. While aging is characterized by central insulin resistance in the face of hyperinsulinemia, the somatotropic axis markedly declines in older humans. Thus, we hypothesized that increasing IGF-1 in the brain may prove to be a novel therapeutic alternative to overcome central insulin resistance and restore whole-body insulin action in aging. Utilizing hyperinsulinemic-euglycemic clamps, we show that old insulin-resistant rats with age-related declines in IGF-1 level demonstrate markedly improved whole-body insulin action, when treated with central IGF-1, as compared to central vehicle or insulin (P IGF-1, but not insulin, suppressed hepatic glucose production and increased glucose disposal rates in aging rats (P IGF-1 action in the brain and periphery provides a 'balance' between its beneficial and detrimental actions. Therefore, we propose that strategies aimed at 'tipping the balance' of IGF-1 action centrally are the optimal approach to achieve healthy aging and longevity in humans. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  12. Relationship between insulin resistance and plasma endothelin in hypertension patients

    International Nuclear Information System (INIS)

    Duan Yongqiang; Wang Zuobing; Yu Hui; Cao Wei; Wang Jing; Li Xiaoqin

    2011-01-01

    To explore the relationship between plasma endothelin and hypertension insulin resistance, and the improvement of insulin resistance in hypertension patients treated with captopril and l-amlodipine, 25 patients with primary hypertension and impaired glucose tolerance were selected and treated by captopril and l-amlodipine. Systolic pressure, diastolic pressure, fasting blood glucose, insulin and insulin antibody were measured before and after treatment and compared with healthy controls. The results showed that the plasma ET-1 level in hypertension group was significantly higher than that of healthy controls (P<0.01), and he plasma ET-1 level was positively correlated with FPG, FINS, Anti-INS, HOMA-IR. The systolic pressure, diastolic pressure, fasting blood glucose, insulin, insulin antibody and insulin resistance index in hypertension patients were decreased significantly after treatment (P<0.05). There is a good correlation between endothelin and insulin resistance index in hypertension patients. Captopril and l-amlodipine had obvious improvement effect on insulin resistance in hypertension patients. (authors)

  13. Increased susceptibility to metabolic dysregulation in a mouse model of Alzheimer's disease is associated with impaired hypothalamic insulin signaling and elevated BCAA levels.

    Science.gov (United States)

    Ruiz, Henry H; Chi, Tiffany; Shin, Andrew C; Lindtner, Claudia; Hsieh, Wilson; Ehrlich, Michelle; Gandy, Sam; Buettner, Christoph

    2016-08-01

    Epidemiologic studies have demonstrated an association between diabetes and dementia. Insulin signaling within the brain, in particular within the hypothalamus regulates carbohydrate, lipid, and branched chain amino acid (BCAA) metabolism in peripheral organs such as the liver and adipose tissue. We hypothesized that cerebral amyloidosis impairs central nervous system control of metabolism through disruption of insulin signaling in the hypothalamus, which dysregulates glucose and BCAA homeostasis resulting in increased susceptibility to diabetes. We examined whether APP/PS1 mice exhibit increased susceptibility to aging or high-fat diet (HFD)-induced metabolic impairment using metabolic phenotyping and insulin-signaling studies. APP/PS1 mice were more susceptible to high-fat feeding and aging-induced metabolic dysregulation including disrupted BCAA homeostasis and exhibited impaired hypothalamic insulin signaling. Our data suggest that AD pathology increases susceptibility to diabetes due to impaired hypothalamic insulin signaling, and that plasma BCAA levels could serve as a biomarker of hypothalamic insulin action in patients with AD. Copyright © 2016 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  14. Will the next generation of basal insulins offer clinical advantages?

    Science.gov (United States)

    Garber, A J

    2014-06-01

    The 21st century has seen the arrival of several insulin analogue products and the refinement of insulin regimens, with widespread advocacy of continuous titration algorithms and earlier initiation of supplementary insulin therapy (predominantly using basal insulins) in type 2 diabetes. Nevertheless, many insulin-treated diabetes patients remain in poor glycaemic control. This might reflect insufficient titration effort or lax adherence, but these issues could in some cases result from concerns about hypoglycaemia. Certainly there is scope for improving the pharmacokinetic/pharmacodynamic (PK/PD) profile of basal insulin, and three new products offer this prospect. Insulin degludec, now in clinical use, and PEGylated insulin lispro, in development, have greatly extended action profiles that result from two very different, but unique, mechanisms. With once-daily dosing, these insulins produce stable PK/PD profiles at steady state, associated with a low incidence of hypoglycaemia. The feasibility of varied daily dose timing has also been confirmed with insulin degludec. High strength formulations of insulin glargine and insulin degludec offer the prospect of a reduced injection number/volume in high dose users, and in the case of glargine, the PK/PD profile might also be favourably modified. This review considers critically the clinical evidence and expectations we should have for these new basal insulins. © 2013 John Wiley & Sons Ltd.

  15. Cinnamon extract improves insulin sensitivity in the brain and lowers liver fat in mouse models of obesity.

    Science.gov (United States)

    Sartorius, Tina; Peter, Andreas; Schulz, Nadja; Drescher, Andrea; Bergheim, Ina; Machann, Jürgen; Schick, Fritz; Siegel-Axel, Dorothea; Schürmann, Annette; Weigert, Cora; Häring, Hans-Ulrich; Hennige, Anita M

    2014-01-01

    Treatment of diabetic subjects with cinnamon demonstrated an improvement in blood glucose concentrations and insulin sensitivity but the underlying mechanisms remained unclear. This work intends to elucidate the impact of cinnamon effects on the brain by using isolated astrocytes, and an obese and diabetic mouse model. Cinnamon components (eugenol, cinnamaldehyde) were added to astrocytes and liver cells to measure insulin signaling and glycogen synthesis. Ob/ob mice were supplemented with extract from cinnamomum zeylanicum for 6 weeks and cortical brain activity, locomotion and energy expenditure were evaluated. Insulin action was determined in brain and liver tissues. Treatment of primary astrocytes with eugenol promoted glycogen synthesis, whereas the effect of cinnamaldehyde was attenuated. In terms of brain function in vivo, cinnamon extract improved insulin sensitivity and brain activity in ob/ob mice, and the insulin-stimulated locomotor activity was improved. In addition, fasting blood glucose levels and glucose tolerance were greatly improved in ob/ob mice due to cinnamon extracts, while insulin secretion was unaltered. This corresponded with lower triglyceride and increased liver glycogen content and improved insulin action in liver tissues. In vitro, Fao cells exposed to cinnamon exhibited no change in insulin action. Together, cinnamon extract improved insulin action in the brain as well as brain activity and locomotion. This specific effect may represent an important central feature of cinnamon in improving insulin action in the brain, and mediates metabolic alterations in the periphery to decrease liver fat and improve glucose homeostasis.

  16. Glycine Increases Insulin Sensitivity and Glutathione Biosynthesis and Protects against Oxidative Stress in a Model of Sucrose-Induced Insulin Resistance

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    Mohammed El-Hafidi

    2018-01-01

    Full Text Available Oxidative stress and redox status play a central role in the link between insulin resistance (IR and lipotoxicity in metabolic syndrome. This mechanistic link may involve alterations in the glutathione redox state. We examined the effect of glycine supplementation to diet on glutathione biosynthesis, oxidative stress, IR, and insulin cell signaling in liver from sucrose-fed (SF rats characterized by IR and oxidative stress. Our hypothesis is that the correction of glutathione levels by glycine treatment leads to reduced oxidative stress, a mechanism associated with improved insulin signaling and IR. Glycine treatment decreases the levels of oxidative stress markers in liver from SF rats and increases the concentrations of glutathione (GSH and γ-glutamylcysteine and the amount of γ-glutamylcysteine synthetase (γ-GCS, a key enzyme of GSH biosynthesis in liver from SF rats. In liver from SF rats, glycine also decreases the insulin-induced phosphorylation of insulin receptor substrate-1 (ISR-1 in serine residue and increases the phosphorylation of insulin receptor β-subunit (IR-β in tyrosine residue. Thus, supplementing diets with glycine to correct GSH deficiency and to reduce oxidative stress provides significant metabolic benefits to SF rats by improving insulin sensitivity.

  17. Circulating complement-C1q TNF-related protein 1 levels are increased in patients with type 2 diabetes and are associated with insulin sensitivity in Chinese subjects.

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    Xuebo Pan

    Full Text Available BACKGROUND: Complement-C1q TNF-related protein 1 (CTRP1, a member of the CTRP superfamily, possesses anti-inflammatory and anti-diabetic effects in mice. However, the clinical relevance of CTRP1 has been seldom explored. The current study aimed to investigate the association of circulating CTRP1 and type 2 diabetes mellitus (T2DM in a Chinese population. DESIGN AND METHODS: Serum CTRP1 and adiponectin levels of 96 T2DM patients and 85 healthy subjects were determined by ELISA, and their associations with adiposity, glucose and lipid profiles were studied. In a subgroup of this study, the 75-g oral glucose tolerance test (OGTT was performed in 20 healthy and 20 T2DM subjects to evaluate the relationship among serum levels of CTRP1 and adiponectin, insulin secretion and insulin sensitivity. RESULTS: Serum CTRP1 levels were significantly increased in patients with T2DM, compared with healthy controls (p<0.001. Similar to adiponectin, serum levels of CTRP1 were significantly correlated to several parameters involved in glucose metabolism and insulin resistance, and independently associated with fasting glucose levels (p<0.05 after BMI and gender adjustments. Furthermore, CTRP1 levels were positively correlated to insulin secretion, while negatively to insulin sensitivity, as measured by OGTT. CONCLUSION: CTRP1 is a novel adipokine associated with T2DM in humans. The paradoxical increase of serum CTRP1 levels in T2DM subjects may be due to a compensatory response to the adverse glucose and lipid metabolism, which warrants further investigation.

  18. A Review of Basal-Bolus Therapy Using Insulin Glargine and Insulin Lispro in the Management of Diabetes Mellitus.

    Science.gov (United States)

    Candido, Riccardo; Wyne, Kathleen; Romoli, Ester

    2018-04-13

    Basal-bolus therapy (BBT) refers to the combination of a long-acting basal insulin with a rapid-acting insulin at mealtimes. Basal insulin glargine 100 U/mL and prandial insulin lispro have been available for many years and there is a substantial evidence base to support the efficacy and safety of these agents when they are used in BBT or basal-plus therapy for patients with type 1 or type 2 diabetes mellitus (T1DM, T2DM). With the growing availability of alternative insulins for use in such regimens, it seems timely to review the data regarding BBT with insulin glargine 100 U/mL and insulin lispro. In patients with T1DM, BBT with insulin glargine plus insulin lispro provides similar or better glycemic control and leads to less nocturnal hypoglycemia compared to BBT using human insulin as the basal and/or prandial component, and generally provides similar glycemic control and rates of severe hypoglycemia to those achieved with insulin lispro administered by continuous subcutaneous insulin infusion (CSII). Studies evaluating BBT with insulin glargine plus insulin lispro in patients with T2DM also demonstrate the efficacy and safety of these insulins. Available data suggest that BBT with insulin glargine and insulin lispro provides similar levels of efficacy and safety in pediatric and adult populations with T1DM and in adult patients and those aged more than 65 years with T2DM. These insulin preparations also appear to be safe and effective for controlling T2DM in people of different ethnicities and in patients with T1DM or T2DM and comorbidities. Eli Lilly and Company.

  19. Skeletal muscle phosphatidylcholine and phosphatidylethanolamine are related to insulin sensitivity and respond to acute exercise in humans.

    Science.gov (United States)

    Newsom, Sean A; Brozinick, Joseph T; Kiseljak-Vassiliades, Katja; Strauss, Allison N; Bacon, Samantha D; Kerege, Anna A; Bui, Hai Hoang; Sanders, Phil; Siddall, Parker; Wei, Tao; Thomas, Melissa; Kuo, Ming Shang; Nemkov, Travis; D'Alessandro, Angelo; Hansen, Kirk C; Perreault, Leigh; Bergman, Bryan C

    2016-06-01

    Several recent reports indicate that the balance of skeletal muscle phosphatidylcholine (PC) and phosphatidylethanolamine (PE) is a key determinant of muscle contractile function and metabolism. The purpose of this study was to determine relationships between skeletal muscle PC, PE and insulin sensitivity, and whether PC and PE are dynamically regulated in response to acute exercise in humans. Insulin sensitivity was measured via intravenous glucose tolerance in sedentary obese adults (OB; n = 14), individuals with type 2 diabetes (T2D; n = 15), and endurance-trained athletes (ATH; n = 15). Vastus lateralis muscle biopsies were obtained at rest, immediately after 90 min of cycle ergometry at 50% maximal oxygen consumption (V̇o2 max), and 2-h postexercise (recovery). Skeletal muscle PC and PE were measured via infusion-based mass spectrometry/mass spectrometry analysis. ATH had greater levels of muscle PC and PE compared with OB and T2D (P insulin sensitivity (both P insulin sensitivity among the entire cohort (r = -0.43, P = 0.01). Muscle PC and PE were altered by exercise, particularly after 2 h of recovery, in a highly group-specific manner. However, muscle PC:PE ratio remained unchanged in all groups. In summary, total muscle PC and PE are positively related to insulin sensitivity while PC:PE ratio is inversely related to insulin sensitivity in humans. A single session of exercise significantly alters skeletal muscle PC and PE levels, but not PC:PE ratio. Copyright © 2016 the American Physiological Society.

  20. Changes in erythrocyte insulin receptors in normal dogs and keeshond dogs with inheritable, early onset, insulin dependent diabetes mellitus

    International Nuclear Information System (INIS)

    Klaassen, J.K.

    1986-01-01

    Validation of a procedure to evaluate insulin receptors on erythrocytes (RBC-IR) in dogs is described. The specific binding of ( 125 I)iodoinsulin to RBC-IR of normal dogs is significantly greater than binding in keeshonds with an inheritable form of early onset diabetes mellitus. This decreased binding was due to a significant decrease in RBC-IR affinity in the diabetic keeshonds. To determine the effect on RBC-IR, normal dogs were treated with either dexamethasone (0.1 mg/kg) or prednisone (0.3 mg/kg) for 10 days: concentrations of plasma cortisol, glucose, and insulin, plus binding characteristics of RBC-IR were determined. In the dexamethasone treated group, plasma glucose concentrations were elevated significantly by day 6 and continued through day 10. Insulin concentrations were elevated significantly by day 3 and remained elevated through day 10. In the prednisone treated group, glucose concentrations were elevated significantly by day 3, while insulin concentrations were elevated significantly by day 8. Maximum binding of RBC-IR was unaffected by prednisone and neither affinities nor receptor numbers were significantly different from day 1. No changes in plasma cortisol concentration were seen. Diabetic keeshonds on daily insulin treatment were removed from exogenous insulin therapy for 48 hours. Significant increases in glucose concentrations were observed, but no significant changes in cortisol, insulin, average receptor binding affinity, or RBC-IR number per cell occurred

  1. Degludec insulin: A novel basal insulin

    OpenAIRE

    Kalra, Sanjay; Unnikrishnan, Ambika Gopalakrishnan; Baruah, Manash; Kalra, Bharti

    2011-01-01

    This paper reviews a novel insulin analogue, degludec, which has the potential to emerge as an ideal basal insulin. It reviews the limitations of existing basal insulin and analogues, and highlights the need for a newer molecule. The paper discusses the potential advantages of degludec, while reviewing its pharmacologic and clinical studies done so far. The paper assesses the potential role of insulin degludec and degludec plus in clinical diabetes practice.

  2. Measuring phospholipase D activity in insulin-secreting pancreatic beta-cells and insulin-responsive muscle cells and adipocytes.

    Science.gov (United States)

    Cazzolli, Rosanna; Huang, Ping; Teng, Shuzhi; Hughes, William E

    2009-01-01

    Phospholipase D (PLD) is an enzyme producing phosphatidic acid and choline through hydrolysis of phosphatidylcholine. The enzyme has been identified as a member of a variety of signal transduction cascades and as a key regulator of numerous intracellular vesicle trafficking processes. A role for PLD in regulating glucose homeostasis is emerging as the enzyme has recently been identified in events regulating exocytosis of insulin from pancreatic beta-cells and also in insulin-stimulated glucose uptake through controlling GLUT4 vesicle exocytosis in muscle and adipose tissue. We present methodologies for assessing cellular PLD activity in secretagogue-stimulated insulin-secreting pancreatic beta-cells and also insulin-stimulated adipocyte and muscle cells, two of the principal insulin-responsive cell types controlling blood glucose levels.

  3. Metabolism and insulin signaling in common metabolic disorders and inherited insulin resistance.

    Science.gov (United States)

    Højlund, Kurt

    2014-07-01

    Type 2 diabetes, obesity and polycystic ovary syndrome (PCOS) are common metabolic disorders which are observed with increasing prevalences, and which are caused by a complex interplay between genetic and environmental factors, including increased calorie intake and physical inactivity. These metabolic disorders are all characterized by reduced plasma adiponectin and insulin resistance in peripheral tissues. Quantitatively skeletal muscle is the major site of insulin resistance. Both low plasma adiponectin and insulin resistance contribute to an increased risk of type 2 diabetes and cardiovascular disease. In several studies, we have investigated insulin action on glucose and lipid metabolism, and at the molecular level, insulin signaling to glucose transport and glycogen synthesis in skeletal muscle from healthy individuals and in obesity, PCOS and type 2 diabetes. Moreover, we have described a novel syndrome characterized by postprandial hyperinsulinemic hypoglycemia and insulin resistance. This syndrome is caused by a mutation in the tyrosine kinase domain of the insulin receptor gene (INSR). We have studied individuals with this mutation as a model of inherited insulin resistance. Type 2 diabetes, obesity and PCOS are characterized by pronounced defects in the insulin-stimulated glucose uptake, in particular glycogen synthesis and to a lesser extent glucose oxidation, and the ability of insulin to suppress lipid oxidation. In inherited insulin resistance, however, only insulin action on glucose uptake and glycogen synthesis is impaired. This suggests that the defects in glucose and lipid oxidation in the common metabolic disorders are secondary to other factors. In young women with PCOS, the degree of insulin resistance was similar to that seen in middle-aged patients with type 2 diabetes. This supports the hypothesis of an unique pathogenesis of insulin resistance in PCOS. Insulin in physiological concentrations stimulates glucose uptake in human skeletal

  4. Insulin resistance alters islet morphology in nondiabetic humans

    DEFF Research Database (Denmark)

    Mezza, Teresa; Muscogiuri, Giovanna; Sorice, Gian Pio

    2014-01-01

    Type 2 diabetes is characterized by poor glucose uptake in metabolic tissues and manifests when insulin secretion fails to cope with worsening insulin resistance. In addition to its effects on skeletal muscle, liver, and adipose tissue metabolism, it is evident that insulin resistance also affects...... pancreatic β-cells. To directly examine the alterations that occur in islet morphology as part of an adaptive mechanism to insulin resistance, we evaluated pancreas samples obtained during pancreatoduodenectomy from nondiabetic subjects who were insulin-resistant or insulin-sensitive. We also compared...... insulin sensitivity, insulin secretion, and incretin levels between the two groups. We report an increased islet size and an elevated number of β- and α-cells that resulted in an altered β-cell-to-α-cell area in the insulin- resistant group. Our data in this series of studies suggest that neogenesis from...

  5. Mitochondrial dysfunction precedes depression of AMPK/AKT signaling in insulin