| 1. |
- Grunnet, Louise G., et al.
(författare)
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Regulation and Function of FTO mRNA Expression in Human Skeletal Muscle and Subcutaneous Adipose Tissue
- 2009
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Ingår i: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 58:10, s. 2402-2408
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE-Common variants in FTO (the fat mass- and obesity-associated gene) associate with obesity and type 2 diabetes. The regulation and biological function of FTO mRNA expression in target tissue is unknown. We investigated the genetic and nongenetic regulation of FTO mRNA in skeletal muscle and adipose tissue and their influence on in vivo glucose and fat metabolism. RESEARCH DESIGN AND METHODS-The FTO rs9939609 polymorphism was genotyped in two twin cohorts: 1) 298 elderly twins aged 62-83 years with glucose tolerance ranging from normal to type 2 diabetes and 2) 196 young (25-32 years) and elderly (58-66 years) nondiabetic twins examined by a hyperinsulinemic-euglycemic clamp including indirect calorimetry. FTO mRNA expression was determined in subcutaneous adipose tissue (n = 226) and skeletal muscle biopsies (n = 158). RESULTS-Heritability of FTO expression in both tissues was low, and FTO expression was not influenced by FTO rs9939609 genotype. FTO mRNA expression in skeletal muscle was regulated by age and sex, whereas age and BMI were predictors of adipose tissue FTO mRNA expression. FTO mRNA expression in adipose tissue was associated with an atherogenic lipid profile. In skeletal muscle, FTO mRNA expression was negatively associated to fat and positively to glucose oxidation rates as well as positively correlated with expression of genes involved in oxidative phosphorylation including PGC1 alpha. CONCLUSIONS-The heritability of FTO expression in adipose tissue and skeletal muscle is low and not influenced by obesity-associated FTO genotype. The age-dependent decline in FTO expression is associated with peripheral defects of glucose and fat metabolism. Diabetes 58:2402-2408, 2009
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| 2. |
- Haugaard, S B, et al.
(författare)
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Sex and muscle structural lipids in obese subjects - an impact on insulin action?
- 2008
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Ingår i: European Journal of Clinical Investigation. - : Wiley. - 0014-2972 .- 1365-2362. ; 38:7, s. 494-501
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Tidskriftsartikel (refereegranskat)abstract
- Background Long-chain polyunsaturated fatty acid (LCPUFA) especially the n-3-FA of skeletal muscle phospholipids may facilitate insulin action, whereas saturated and trans-FA act oppositely. Community studies show that non-diabetic weight matched obese men and women display similar insulin resistance, despite the fact that an android fat distribution is detrimental to insulin action. The increased extramyocellular fat mass of obese women may act in a paracrine manner such that its release of free FA and cytokines may hamper in situ desaturation and elongation of FA in skeletal muscle phospholipids. Material and methods To test the hypothesis that obese women may display an inferior FA composition compared to obese men, the FA composition of skeletal muscle phospholipids was determined in vastus lateralis biopsies obtained from 12 non-diabetic obese women with a typical gynoid fat distribution, nine non-diabetic obese men with a typical android fat distribution and 12 (seven females) lean age matched healthy controls (body mass index 34.6 +/- 1.0 kg m(-2), 36.5 +/- 1.2 and 22.5 +/- 0.5; age 47 +/- 2 years, 51 +/- 3 and 49 +/- 2). Results Obese women displayed decreased LCPUFA n-3 and ratio of n-3/n-6 PUFA, whereas trans-FA and palmitic-FA (C16 : 0) were increased compared to obese men and controls (all Ps < 0.05). Plasma high-density lipoprotein cholesterol (HDL-C), triglycerides and a marker of insulin sensitivity were similar between obese women and men but impaired compared to controls (Ps < 0.05). Conclusions The data support the hypothesis that insulin resistant non-diabetic obese men display a more optimal skeletal muscle phospholipid FA composition than their female counterparts, which may be a mechanism to compensate the detrimental effect on insulin action of an android fat distribution.
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| 3. |
- Haugaard, Steen B., et al.
(författare)
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Skeletal muscle structural lipids improve during weight-maintenance after a very low calorie dietary intervention
- 2009
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Ingår i: Lipids in Health and Disease. - 1476-511X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: The objective was to investigate in a group of obese subjects the course in skeletal muscle phospholipid (SMPL) fatty acids (FA) during a 24-weeks weight maintenance program, which was preceded by a successful very low calorie dietary intervention (VLCD). Special focus was addressed to SMPL omega-3 FA, which is a lipid entity that influences insulin action. Methods: Nine obese subjects (BMI = 35.7 +/- 1.0 kg/m(2)), who had completed an 8 weeks VLCD (weight-loss = -9.7 +/- 1.6 kg, P < 0.001), had obtained skeletal muscle biopsies (vastus lateralis) before and after a dietician-guided 24-weeks weight-maintenance program (-1.2 +/- 1.5 kg, P = ns). SMPL FA composition was determined by gas liquid chromatography. During the preceding VLCD, insulin sensitivity (HOMA-IR) and glycemic control (HbA1c) improved but no change in SMPL omega-3 FA was observed. During the weight-maintenance program five subjects received the pancreas lipase inhibitor Orlistat 120 mg t.i.d. versus placebo. Results: HOMA-IR and HbA1c stabilized and SMPL total omega-3 FA, docosahexaenoic acid and ratio of n-3/n-6 polyunsaturated FA increased by 24% (P < 0.01), 35% (P < 0.02) and 26% (P < 0.01), respectively, whereas saturated and monounsaturated FA did not change. Plasma total-cholesterol and LDL-cholesterol, which decreased during the VLCD, reverted to pre-VLCD levels (P < 0.01). Orlistat therapy was associated with weight-loss (P < 0.05), trends for better glycemic control (P = 0.15) and greater increase in SMPL docosahexaenoic acid (P = 0.12) but similar reversal of plasma cholesterols compared to placebo. Conclusion: The data are consistent with the notion that greater SMPL omega-3 FA obtained during a weight-maintenance program may play a role for preserving insulin sensitivity and glycemic control being generated during a preceding VLCD.
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| 4. |
- Larsen, Claus M., et al.
(författare)
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Interleukin-1-receptor antagonist in type 2 diabetes mellitus
- 2007
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 356:15, s. 1517-1526
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Tidskriftsartikel (refereegranskat)abstract
- Background: The expression of interleukin-1-receptor antagonist is reduced in pancreatic islets of patients with type 2 diabetes mellitus, and high glucose concentrations induce the production of interleukin-1(beta) in human pancreatic beta cells, leading to impaired insulin secretion, decreased cell proliferation, and apoptosis. Methods: In this double-blind, parallel-group trial involving 70 patients with type 2 diabetes, we randomly assigned 34 patients to receive 100 mg of anakinra (a recombinant human interleukin-1-receptor antagonist) subcutaneously once daily for 13 weeks and 36 patients to receive placebo. At baseline and at 13 weeks, all patients underwent an oral glucose-tolerance test, followed by an intravenous bolus of 0.3 g of glucose per kilogram of body weight, 0.5 mg of glucagon, and 5 g of arginine. In addition, 35 patients underwent a hyperinsulinemic-euglycemic clamp study. The primary end point was a change in the level of glycated hemoglobin, and secondary end points were changes in beta-cell function, insulin sensitivity, and inflammatory markers. Results: At 13 weeks, in the anakinra group, the glycated hemoglobin level was 0.46 percentage point lower than in the placebo group (P=0.03); C-peptide secretion was enhanced (P=0.05), and there were reductions in the ratio of proinsulin to insulin (P=0.005) and in levels of interleukin-6 (P<0.001) and C-reactive protein (P=0.002). Insulin resistance, insulin-regulated gene expression in skeletal muscle, serum adipokine levels, and the body-mass index were similar in the two study groups. Symptomatic hypoglycemia was not observed, and there were no apparent drug-related serious adverse events. Conclusions: The blockade of interleukin-1 with anakinra improved glycemia and beta-cell secretory function and reduced markers of systemic inflammation.
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| 5. |
- Larsen, Claus M., et al.
(författare)
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Sustained Effects of Interleukin-1 Receptor Antagonist Treatment in Type 2 Diabetes
- 2009
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Ingår i: Diabetes Care. - : American Diabetes Association. - 1935-5548 .- 0149-5992. ; 32:9, s. 1663-1668
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE - Interleukin (IL)-1 impairs insulin secretion and induces P-cell apoptosis. Pancreatic beta-cell IL-1 expression is increased and interleukin-1 receptor antagonist (IL-1Ra) expression reduced in patients with type 2 diabetes. Treatment with recombinant IL-1Ra improves glycemia and P-cell function and reduces inflammatory markers in patients with type 2 diabetes. Here we investigated the durability of these responses. RESEARCH DESIGN AND METHODS - Among 70 ambulatory patients who had type 2 diabetes, A1C >7.5%, and BMI >27 kg/m(2) and were randomly assigned to receive 13 weeks of anakinra, a recombinant human IL-1Ra, or placebo, 67 completed treatment and were included in this double-blind 39-week follow-up study. Primary outcome was change in P-cell function after anakinra withdrawal. Analysis was done by intention to treat. RESULTS - Thirty-nine weeks after anakinra withdrawal, the proinsulin-to-insulin (PI/I) ratio but not stimulated C-peptide remained improved (by -0.07 [95% CI -0.14 to -0.02], P = 0.011) compared with values in placebo-treated patients. Interestingly, a subgroup characterized by genetically determined low baseline IL-1Ra serum levels maintained the improved stimulated C-peptide obtained by 13 weeks of IL-1Ra treatment. Reductions in C-reactive protein (-3.2 mg/l [-6.2 to -1.1], P = 0.014) and in IL-6 (-1.4 mg/l [-2.6 to -0.3], P = 0.036) were maintained until the end of study. CONCLUSIONS - IL-1 blockade with anakinra induces improvement of the PIA ratio and markers of systemic inflammation lasting 39 weeks after treatment withdrawal.
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| 6. |
- Ling, Charlotte, et al.
(författare)
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Genetic and epigenetic factors are associated with expression of respiratory chain component NDUFB6 in human skeletal muscle.
- 2007
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Ingår i: The Journal of clinical investigation. - 0021-9738. ; 117:11, s. 3427-35
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Tidskriftsartikel (refereegranskat)abstract
- Insulin resistance and type 2 diabetes are associated with decreased expression of genes that regulate oxidative phosphorylation in skeletal muscle. To determine whether this defect might be inherited or acquired, we investigated the association of genetic, epigenetic, and nongenetic factors with expression of NDUFB6, a component of the respiratory chain that is decreased in muscle from diabetic patients. Expression of NDUFB6 was influenced by age, with lower gene expression in muscle of elderly subjects. Heritability of NDUFB6 expression in muscle was estimated to be approximately 60% in twins. A polymorphism in the NDUFB6 promoter region that creates a possible DNA methylation site (rs629566, A/G) was associated with a decline in muscle NDUFB6 expression with age. Although young subjects with the rs629566 G/G genotype exhibited higher muscle NDUFB6 expression, this genotype was associated with reduced expression in elderly subjects. This was subsequently explained by the finding of increased DNA methylation in the promoter of elderly, but not young, subjects carrying the rs629566 G/G genotype. Furthermore, the degree of DNA methylation correlated negatively with muscle NDUFB6 expression, which in turn was associated with insulin sensitivity. Our results demonstrate that genetic, epigenetic, and nongenetic factors associate with NDUFB6 expression in human muscle and suggest that genetic and epigenetic factors may interact to increase age-dependent susceptibility to insulin resistance.
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| 7. |
- Lund, Soren S., et al.
(författare)
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Combining insulin with metformin or an insulin secretagogue in non-obese patients with type 2 diabetes: 12 month, randomised, double blind trial
- 2009
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Ingår i: BMJ (International Edition). - : BMJ. - 0959-8146 .- 0959-8138 .- 1468-5833. ; 339
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To study the effect of insulin treatment in combination with metformin or an insulin secretagogue, repaglinide, on glycaemic regulation in non-obese patients with type 2 diabetes. Design Randomised, double blind, double dummy, parallel trial. Setting Secondary care in Denmark between 2003 and 2006. Participants Non-obese patients (BMI <= 27) with preserved beta cell function. Interventions After a four month run-in period with repaglinide plus metformin combination therapy, patients with a glycated haemoglobin (HbA(1c)) concentration of 6.5% or more were randomised to repaglinide 6 mg or metformin 2000 mg. All patients also received biphasic insulin aspart 70/30 (30% soluble insulin aspart and 70% intermediate acting insulin aspart) 6 units once a day before dinner for 12 months. Insulin dose was adjusted aiming for a fasting plasma glucose concentration of 4.0-6.0 mmol/l. The target of HbA(1c) concentration was less than 6.5%. Treatment was intensified to two or three insulin injections a day if glycaemic targets were not reached. Main outcome measure HbA(1c) concentration. Results Of the 459 patients who were eligible, 102 were randomised, and 97 completed the trial. Patients had had type 2 diabetes for approximately 10 years. At the end of treatment, HbA(1c) concentration was reduced by a similar amount in the two treatment groups (insulin plus metformin: mean (standard deviation) HbA(1c) 8.15% (1.32) v 6.72% (0.66); insulin plus repaglinide: 8.07% (1.49) v 6.90% (0.68); P=0.177). Total daily insulin dose and risk of hypoglycaemia were also similar in the two treatment groups. Weight gain was less with metformin plus biphasic insulin aspart 70/30 than with repaglinide plus biphasic insulin aspart 70/30 (difference in mean body weight between treatments -2.51 kg, 95% confidence interval -4.07 to -0.95). Conclusions In non-obese patients with type 2 diabetes and poor glycaemic regulation on oral hypoglycaemic agents, overall glycaemic regulation with insulin in combination with metformin was equivalent to that with insulin plus repaglinide. Weight gain seemed less with insulin plus metformin than with insulin plus repaglinide.
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| 8. |
- Lund, S. S., et al.
(författare)
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Effect of adjunct metformin treatment on levels of plasma lipids in patients with type 1 diabetes
- 2009
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Ingår i: Diabetes, Obesity and Metabolism. - : Wiley. - 1462-8902 .- 1463-1326. ; 11:10, s. 966-977
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Tidskriftsartikel (refereegranskat)abstract
- Background In addition to its glucose-lowering effect, metformin treatment has been suggested to improve lipidaemia in patients with type 2 diabetes. In contrast, in patients with type 1 diabetes (T1DM), information about the effect of metformin treatment on lipidaemia is limited. In this study, we report the effect of a 1-year treatment with metformin vs. placebo on plasma lipids in T1DM patients and persistent poor glycaemic control. Methods One hundred T1DM patients with haemoglobinA(1c) (HbA(1c)) >= 8.5% during the year before enrolment entered a 1-month run-in period on placebo treatment. Thereafter, patients were randomized (baseline) to treatment with either metformin (1000 mg twice daily) or placebo for 12 months (double masked). Patients continued ongoing insulin therapy and their usual outpatient clinical care. Outcomes were assessed at baseline and after 1 year. Results After 1 year, in those patients who did not start or stop statin therapy during the trial, metformin treatment significantly reduced total and LDL cholesterol by approximately 0.3 mmol/l compared with placebo (p = 0.021 and p = 0.018 respectively). Adjustment for statin use or known cardiovascular disease did not change conclusions. In statin users (metformin: n = 22, placebo: n = 13), metformin significantly lowered levels of LDL and non-HDL cholesterol by approximately 0.5 mmol/l compared with placebo (adjusted for changes in statin dose or agent: p = 0.048 and p = 0.033 respectively). HbA(1c) (previously reported) was not significant different between treatments. Conclusion In patients with poorly controlled T1DM, at similar glycaemic levels, adjunct metformin therapy during 1 year significantly lowered levels of proatherogenic cholesterolaemia independent of statin therapy.
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| 9. |
- Lund, Soren S, et al.
(författare)
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Impact of metformin versus repaglinide on non-glycaemic cardiovascular risk markers related to inflammation and endothelial dysfunction in non-obese patients with type 2 diabetes
- 2008
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 158:5, s. 631-641
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Tidskriftsartikel (refereegranskat)abstract
- Objective: In patients with type 2 diabetes mellitus (T2DM), biomarkers reflecting inflammation and endothelial dysfunction have been linked to cardiovascular disease (CVD biomarkers) and metabolic regulation. In T2DM patients, metformin and insulin secretagogues have demonstrated equal anti-hyperglycaemic potency. Here, we report the effect of metformin versus an insulin secretagogue, repaglinide, on CVD biomarkers in non-obese T2DM patients. Design and methods: Single-centre, double-masked, double-dummy, crossover study during 2x4 months involving 96 non-obese (body mass index <= 27kg/m(2)) insulin-naive T2DM patients. At enrolment, previous oral hypoglycaemic agents were stopped and the patients entered a 1-month run- on diet-only treatment. Hereafter, patients were randomized to either 2 mg repaglinide thrice daily followed by 1 g metformin twice daily or vice versa each during 4 months with a 1-month washout between interventions. Results: Levels of tumour necrosis factor-alpha, plasminogen activator inhibitor-1 antigen, tissue-type plasminogen activator antigen, von Willebrand factor, soluble intercellular adhesion molecule-1 and soluble E-selectin were significantly lower during metformin versus repaglinide treatments. In contrast, Amadori albumin and heart rate were higher during metformin versus repaglinide. Levels of interleukin-6. fibrinogen, soluble vascular cell adhesion molecule-1, asymmetric dimethylarginine and advanced glycation end products as well as glycaemic levels (previously reported) and 24-h blood pressure were similar between treatments. Adjustment for known macrovascular disease did not affect the between-treatment: effects. Conclusions: In non-obese T2DM patients, metformin was more effective in reducing selected biomarkers reflecting inflammation and endothelial dysfunction compared with repaglinide despite similar glycaemic levels between treatments.
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| 10. |
- Lund, Soren S, et al.
(författare)
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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
- 2008
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 158:1, s. 35-46
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Tidskriftsartikel (refereegranskat)abstract
- 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 (HbA(1c)). Whether the same apply for postprandial glucose and lipid metabolism is unknown. Here. we compared the effect of metformin versus repaglinide on postprandial metabolism in non-obese T2DM patients. Design: Single-centre. double-masked, double-dummy. crossover study during 2 X 4 months involving 96 non-obese (body mass index:! 2 7 kg/m(2)) insulin-naive T2DM patients. At enrolment, patients stopped prior oral hypoglycaemic agents therapies and after a 1-month run-in period on diet-only treatment, patients were randomized to repaglinide (2 mg) thrice daily followed by metformin (1 g) twice daily or vice versa each during 4 months with 1-month washout between interventions. Methods: Postprandial metabolism was evaluated by a standard test meal (3 515 kJ: 54%, fat, 13% protein and 33%, carbohydrate) with blood sampling 0-6 h postprandially. Results: Fasting levels and total area under the curve (AUC) for plasma glucose, triglycerides and free fatty acids (FFA) changed equally between treatments. In contrast, fasting levels and AUC of total cholesterol. low-density lipoprotein (LDL) cholesterol, non-high-density lipoprotein (non-HDL) cholesterol and serum insulin were lower during metformin than repaglinide (mean (95% confidence intervals), LDL cholesterol difference metformin versus repaglinide: AUC: -0.17mmol/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 chotesterolaemia and insulinaemia compared with repaglinide. These data support prescription of metformin as the preferred drug in non-obese patients with T2DM targeting fasting and postprandial glucose and lipid metabolism.
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