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Background. Ramadan is the sacred month of the Islamic Hijri (lunar) calendar, and during this entire month, healthy adult Muslims abstain from eating and drinking from dawn to sunset. Muslims with Type 2 Diabetes Mellitus (T2DM) who choose to fast during Ramadan encounter major risks such as hypoglycemia, hyperglycemia, diabetic ketoacidosis, dehydration, and thrombosis. Although patients with poor glycemic control and on multiple insulin injections are at high risk and exempt from fasting, many still insist on it. Thus, healthcare professionals play a pivotal role in managing diabetes-related complications in patients who fast during Ramadan. However, there is a lack of standard guidelines to be followed in association with structured education and administration of drugs and dosage. Therefore, we performed a systematic review and meta-analysis of the literature to determine the safety and efficacy of different classes of drugs and the importance of structured education during Ramadan. Methods. In this review, an extensive PubMed search was performed to obtain literature on T2DM patients who fast during the month of Ramadan until the year 2020. Preference was given to fully downloadable articles. The articles were extracted based on the eligibility criteria. The extracted data were analyzed using Review Manager software version 5.3. Results. A total of 32 articles were included for the review and 7 studies for meta-analysis. Majority of the studies demonstrated the importance of structured education either as a group session or as a one-on-one session with the healthcare professionals in preventing diabetes-related risks during Ramadan. As far as glucose-lowering drugs are concerned, DPP-4 inhibitor combined with metformin remains the drug of choice for T2DM patients who fast during Ramadan. The newer class of glucose-lowering agents appear to lower the risk of hypoglycemia in comparison with sulphonylureas, while among sulphonylureas gliclazide is relatively safe. The meta-analysis indicates that DPP-4 inhibitors would significantly reduce the risk of hypoglycemia as compared to sulphonylurea (odds ratio=0.38, 95% CI: 0.26 to 0.55, p < 0.00001). Conclusion. The results of our systematic review show that structured education and counselling by healthcare professionals can be an effective tool in preventing complications associated with fasting during Ramadan in people with T2DM. Additionally, the safest class of oral glucose-lowering drugs preferred during Ramadan fasting in T2DM patients is DPP-4 inhibitors.

Background. Living kidney donor safety requires reliable long-term follow-up of renal function after donation. The current study aimed to define the precision and accuracy of post-donation estimated glomerular filtration rate (eGFR) slopes compared with measured GFR (mGFR) slopes.Methods. In 349 donors (age 51 +/- 10, 54% female), we analysed eGFR according to the 2009 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault/body surface area (CG/BSA), creatinine clearance (CrCl) and mGFR (I-125-iothalamate) changes from 3 months until 5 years post-donation.Results. Donors had a pre-donation mGFR of 116 +/- 23 mL/min, at 3 months post-donation mGFR was 73 +/- 14 mL/min and at 5 years it was 79 +/- 16 mL/min. Between 3 months and 5 years post-donation, 28% of donors had a declining mGFR (-0.82 +/- 0.79 mL/min/year), 47% were stable and 25% had an increasing mGFR. Overall, eGFR equations showed good slope estimates (bias eGFR(CKD-EPI) 0.13 +/- 2.16 mL/min/year, eGFR(MDRD) 0.19 +/- 2.10 mL/min/year, eGFR(CG/BSA) -0.08 +/- 2.06 mL/min/year, CrCl -0.12 +/- 4.75 mL/min/year), but in donors with a decreasing mGFR the slope was underestimated (bias eGFR(CKD-EPI) 1.41 +/- 2.03 mL/min/year, eGFR(MDRD) 1.51 +/- 1.96 mL/min/year, eGFR(CG/BSA) 1.20 +/- 1.87 mL/min/ year). The CrCl had a high imprecision [bias interquartile range -1.51-3.41mL/min/year].Conclusions. All eGFR equations underestimated GFR slopes in donors with a declining GFR between 3 months and 5 years post-donation. This study underlines the value of mGFR in the follow-up of donors with risk of progressive GFR loss.

Aims: To examine the distribution of liver fat (LFAT) in non-diabetic subjects and test whether the fat in the right as compared to the left lobe correlates better with components of the metabolic syndrome or not. Methods: In this cross sectional study, we determined LFAT by H-1-MRS in the right lobe (LFAT%(MRS)), and by MRI (LFAT%(MRI)) in four regions of interest (ROIs 1-4, two in the right and two in the left lobe) in 97 non-diabetic subjects (age range 22-74 years, BMI 18-41 kg/m(2)) and compared the accuracy of LFAT(MRI) in the different ROIs in diagnosing non-alcoholic fatty liver disease (NAFLD) using areas under the receiver operator characteristic (AUROC) curves. Results: 38% of the subjects had NAFLD (LFAT%(MRS)). LFAT%(MRI) was significantly higher in the right (5.7 +/- 0.5%) than the left (5.1 +/- 0.4%) lobe (p

The majority of fat in the human body is stored as triacylglycerols in white adipose tissue. In the obese state, adipose tissue mass expands and excess lipids are stored in non-adipose tissues, such as skeletal muscle. Lipids are stored in skeletal muscle in the form of small lipid droplets. Although originally viewed as dull organelles that simply store lipids as a consequence of lipid overflow from adipose tissue, lipid droplets are now recognized as key components in the cell that exert a variety of relevant functions in multiple tissues (including muscle). Here, we review the effect of diet and exercise interventions on myocellular lipid droplets and their putative role in insulin sensitivity from a human perspective. We also provide an overview of lipid droplet biology and identify gaps for future research.

The majority of fat in the human body is stored as triacylglycerols in white adipose tissue. In the obese state, adipose tissue mass expands and excess lipids are stored in non-adipose tissues, such as skeletal muscle. Lipids are stored in skeletal muscle in the form of small lipid droplets. Although originally viewed as dull organelles that simply store lipids as a consequence of lipid overflow from adipose tissue, lipid droplets are now recognized as key components in the cell that exert a variety of relevant functions in multiple tissues (including muscle). Here, we review the effect of diet and exercise interventions on myocellular lipid droplets and their putative role in insulin sensitivity from a human perspective. We also provide an overview of lipid droplet biology and identify gaps for future research.

AIMS Sulodexide is a highly purified mixture of glycosaminoglycans that has been studied for its anti-albuminuric potential. Considering the effects of glycosaminoglycans on endothelial function and sodium homeostasis, we hypothesized that sulodexide may lower blood pressure (BP). In this meta-analysis, we therefore investigated the antihypertensive effects of sulodexide treatment. METHODS We selected randomized controlled trials that investigated sulodexide treatment of at least 4 weeks and measured BP at baseline and after treatment. Two reviewers independently extracted data on study design, risk of bias, population characteristics and outcome measures. In addition, we contacted authors and pharmaceutical companies to provide missing data. RESULTS Eight studies, totalling 3019 subjects (mean follow-up 4.4 months) were included. Mean age was 61 years and mean baseline BP was 135/75 mmHg. Compared with control treatment, sulodexide resulted in a significant systolic (2.2 mmHg [95% CI 0.3, 4.1], P = 0.02) and diastolic BP reduction (1.7 mmHg [95% CI 0.6, 2.9], P = 0.004). Hypertensive patients displayed the largest systolic BP and diastolic BP reductions (10.2/5.4 mmHg, P

The need to develop an insulin delivery system that can closely mimic physiologically induced changes in prandial insulin release has been a major research target since the discovery of insulin. The challenges facing existing insulin delivery systems, related to relatively slow pharmacokinetics and pharmacodynamics, have been further highlighted by rapid advances in diabetes technology and progress in artificial pancreas research. Despite the growing interest in alternative routes of insulin administration, the subcutaneous route remains-at least for now-the preferred route for insulin administration. In this article, we review efforts aimed at developing subcutaneously injected ultrafast-acting insulin and measures aimed at enhancing insulin absorption, focusing on local warming devices.

Recent advances in the understanding of the coagulopathy in chronic liver disease have provided a strong support for anticoagulation as a new therapeutic paradigm for patients with cirrhosis. Laboratory studies indicate that the net effect of changes in hemostasis in many patients with chronic liver disease is a hypercoagulable status. In turn, clinical thrombosis is increasingly recognized as a complication of liver disease. When occurring within the liver, thrombosis may even progress the disease course. Exciting preliminary data regarding the potential of low-molecular-weight heparin to slow down the progression of liver disease indicate that this class of drugs may improve outcome without a major increase in bleeding risk. However, this new era for antithrombotic therapy in chronic liver disease is still hindered by a persistent false notion that patients with cirrhosis are "auto-anticoagulated" by their underlying liver disease. In addition, there is insufficient clinical evidence on safety and efficacy of anticoagulant therapy in cirrhosis and the studies conducted so far are limited by small sample sizes, uncontrolled treatment arms, or by their retrospective nature. Finally, a lack of knowledge on how or when to monitor antithrombotic treatment to optimize the risk-benefit ratio has restricted a widespread application of anticoagulant treatment in clinical management algorithms. Nonetheless, by systematically covering possibilities and pitfalls, this review highlights the potential of antithrombotic therapy to improve the quality of life and the clinical outcome of patients with chronic liver disease. (C) 2014 Elsevier Ltd. All rights reserved.

Drug efficacy is ascertained using clinically meaningful outcomes that directly affect the well-being of patients. However, in studies of chronic kidney disease progression, clinically meaningful outcomes like end-stage renal disease take a long time to occur. The use of surrogate end points/markers as replacement for clinical outcomes is tempting as it may reduce sample size requirements, shorten follow-up time, facilitate trial conduct, and allow the performance of intervention trials in earlier stages of kidney disease to be carried out. We here reviewed recent data supporting the use of microalbuminuria as a valid surrogate end point in clinical trials of chronic kidney disease. We provide data that albuminuria is associated with worse renal prognosis and that pharmacological treatment aimed to reduce albuminuria levels delays the progression of renal disease and the occurrence of clinical outcomes. Furthermore, we review new studies showing that albumin is not only an inert molecule but also directly affects the function of several cell types in the kidney and may have a pathogenic role in renal disease. Accepting microalbuminuria as a surrogate marker for renal outcomes will lead to less resource-consuming hard outcome trials, will accelerate the development of drugs for chronic kidney disease, and enable earlier access of these drugs to individual patients.

Strategies aimed at mimicking or enhancing the action of the incretin hormone glucagon-like peptide 1 (GLP-1) therapeutically improve glucose-stimulated insulin secretion (GSIS); however, it is not clear whether GLP-1 directly drives insulin secretion in pancreatic islets. Here, we examined the mechanisms by which GLP-1 stimulates insulin secretion in mouse and human islets. We found that GLP-1 enhances GSIS at a half-maximal effective concentration of 0.4 pM. Moreover, we determined that GLP-1 activates PLC, which increases submembrane diacylglycerol and thereby activates PKC, resulting in membrane depolarization and increased action potential firing and subsequent stimulation of insulin secretion. The depolarizing effect of GLP-1 on electrical activity was mimicked by the PKC activator PMA, occurred without activation of PKA, and persisted in the presence of PKA inhibitors, the KATP channel blocker tolbutamide, and the L-type Ca(2+) channel blocker isradipine; however, depolarization was abolished by lowering extracellular Na(+). The PKC-dependent effect of GLP-1 on membrane potential and electrical activity was mediated by activation of Na(+)-permeable TRPM4 and TRPM5 channels by mobilization of intracellular Ca(2+) from thapsigargin-sensitive Ca(2+) stores. Concordantly, GLP-1 effects were negligible in Trpm4 or Trpm5 KO islets. These data provide important insight into the therapeutic action of GLP-1 and suggest that circulating levels of this hormone directly stimulate insulin secretion by β cells.

Background/Aim: We tested the hypothesis that a persistent reduction in free fatty acid (FFA) levels improves cardiac function and systemic insulin sensitivity via a reduction in the myocardial and skeletal muscle adiposities and a modulation in adipokine release.Methods: Study subjects (body mass index 22-30 kg/m(2), 57 +/- 3 yr old) underwent magnetic resonance imaging and spectroscopy to measure the cardiac function and the amounts of fat inside and around the myocardium and skeletal muscle, before (n = 10) and after acute (n = 8) and 1 wk (n = 7, one excluded from analysis) lowering of circulating FFA by acipimox. Circulating adipokines (leptin, adiponectin, resistin, TNF alpha, IL-6, IL-8, plasminogen activator inhibitor-I, macrophage chemoattractant protein-1) were measured.Results: The ejection fraction (62 +/- 2 vs. 56 +/- 1%, P = 0.0035), cardiac output (6.6 +/- 0.3 vs. 5.5 +/- 0.2 liters/min, P = 0.0018), and forward work (708 +/- 49 vs. 539 +/- 44 mmHg x liters/min, P = 0.018) were significantly lower after 1 wk of FFA lowering. In the six subjects undergoing all sessions, the stroke and end-diastolic volumes were also reduced, insulin sensitivity was increased by 33%, and adiponectinemia was decreased (-26%, P = 0.03). No change in intracellular cardiac and skeletal muscle triglyceride levels was observed. Metabolic changes correlated with the lowering of FFA. The reduction in cardiac function was related with changes in glycemia and insulin sensitivity, whereas the deflection in left ventricular work was correlated with the decline in FFA, lipid, and blood pressure levels.Conclusions: A 1-wk FFA depletion suppressed cardiac function and improved insulin sensitivity. Intracellular triglyceride deposits in the heart and skeletal muscle played no role in the observed changes. Our data show that FFA participate in the physiological regulation of adipokine levels. (J Clin Endocrinol Metab 97: 3277-3284, 2012)

A low fat oxidative capacity has been linked to muscle diacylglycerol (DAG) accumulation and insulin resistance. Alternatively, a low fat oxidation rate may stimulate glucose oxidation, thereby enhancing glucose disposal. Here, we investigated whether an ethyl-2-[6-(4-chlorophenoxy)hexyl]-oxirane-2-carboxylate (etomoxir)-induced inhibition of fat oxidation leads to muscle fat storage and insulin resistance. An intervention in healthy male subjects was combined with studies in human primary myotubes. Furthermore, muscle DAG and triacylglycerol (TAG), mitochondrial function, and insulin signaling were examined in etomoxir-treated C57bl6 mice. In humans, etomoxir administration increased glucose oxidation at the expense of fat oxidation. This effect was accompanied by an increased abundance of GLUT4 at the sarcolemma and a lowering of plasma glucose levels, indicative of improved glucose homeostasis. In mice, etomoxir injections resulted in accumulation of muscle TAG and DAG, yet improved insulin-stimulated GLUT4 translocation. Also in human myotubes, insulin signaling was improved by etomoxir, in the presence of increased intramyocellular lipid accumulation. These insulin-sensitizing effects in mice and human myotubes were accompanied by increased phosphorylation of AMP-activated protein kinase (AMPK). Our results show that a reduction in fat oxidation leading to accumulation of muscle DAG does not necessarily lead to insulin resistance, as the reduction in fat oxidation may activate AMPK.

Renal insufficiency is common in patients with heart failure (HF), with both acute kidney injury and worsening renal function being associated with poor prognosis. The interplay between cardiac and renal failure has been termed the cardiorenal syndrome and is currently the subject of intense investigation. Urinary biochemistry has several advantages over blood or serum analyses, including lower costs, better patient comfort, and higher sensitivity to renal injury. However, urinalysis is currently not part of routine daily practice in cardiology. Recent advances in proteomics have allowed identification of numerous novel urinary biomarkers, many of which show promise in HF populations. In this review, we aim to provide an overview of both traditional and novel urinary biomarkers, examining evidence for diagnostic and prognostic value in HF as well as potential clinical utility.

Background and aims: We aimed to determine the effect of short-term dietary sodium restriction on plasma total cholesterol, LDL-C, HDL-C, triglycerides, apolipoprotein (apo) A-I, apo B and high molecular weight (HMW) adiponectin in non-obese, normotensive young men. Glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma renin activity (PRA) and aldosterone were also measured.Methods and results: Sixty-five men, aged 23 +/- 7 years, were randomly studied on a high sodium intake (HS, 228 +/- 77 mmol Na+/24 h) and a low sodium intake (LS, 36 +/- 27 mmol Na+/24 h), each period lasting 1 week. LS decreased GFR and ERPF and increased PRA and aldosterone (p Conclusion: Short term sodium restriction modestly decreases HDL-C, apo A-I and HMW-adiponectin in healthy men. Changes in GFR and ERPF and in the renin-angiotensin-aldosterone system as induced by LS may be involved in these responses. (C) 2010 Elsevier B. V. All rights reserved.

Ectopic fat accumulation has been linked to lipotoxic events, including the development of insulin resistance in skeletal muscle. Indeed, intramyocellular lipid storage is strongly associated with the development of type 2 diabetes. Research during the last two decades has provided evidence for a role of lipid intermediates like diacylglycerol and ceramide in the induction of lipid-induced insulin resistance. However, recently novel data has been gathered that suggest that the relation between lipid intermediates and insulin resistance is less straightforward than has been previously suggested, and that there are several routes towards lipid-induced insulin resistance. For example, research in this field has shifted towards imbalances in lipid metabolism and lipid droplet dynamics. Next to imbalances in key lipogenic and lipolytic proteins, lipid droplet coat proteins appear to be essential for proper intramyocellular lipid storage, turnover and protection against lipid-induced insulin resistance. Here, we discuss the current knowledge on lipid-induced insulin resistance in skeletal muscle with a focus on the evidence from human studies. Furthermore, we discuss the available data that provides supporting mechanistic information.

Background. Chronic kidney disease (CKD) typically extends over decades. Longitudinal monitoring of kidney function in CKD is thus of great importance. Here, we retrospectively evaluate use of the Modification of Diet in Renal Disease (MDRD) study and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations to monitor long-term course of kidney function and to identify individuals with progressive kidney function loss.Methods. Patients were selected from our outpatient clinic for having four glomerular filtration rate measurements (mGFR, I-125-iothalamate) and at least >= 4 years of follow-up. Renal function slopes were obtained by within-individual linear regression.Results. Sixty-five nondiabetic CKD patients (40 male, mean baseline age 44 +/- 12 years) with a median (range) of 9 (4-16) mGFR measurements and a median follow-up of 11 (4-33) years were included. Both equations significantly underestimated mGFR/(BSA) at baseline and at the end of follow-up. mGFR slope was significantly underestimated by the MDRD study but not by CKD-EPI equation (slopes -1.41 +/- 2.06, -1.07 +/- 1.72 and -1.39 +/- 1.77 mL/min/1.73m(2)/year, respectively). Sensitivity and specificity to identify progressive kidney function loss (mGFR/(BSA) slope > 1.5 mL/min/1.73m(2)/ year, n = 23) were 78 and 88% for the MDRD study and 91 and 80% for CKD-EPI equation. In the subgroup of progressors, both MDRD study and CKD-EPI equation underestimated the rate of mGFR loss (P Conclusions. Long-term course of mGFR is reasonably well estimated by CKD-EPI and slightly underestimated by MDRD study equation. Patients with progressive kidney function loss may, however, not be reliably identified, so caution is warranted when using these equations in clinical practice.

Metformin is widely used in the treatment of diabetes mellitus type 2 where it reduces insulin resistance and diabetes-related morbidity and mortality. Population-based studies show that metformin treatment is associated with a dose-dependent reduction in cancer risk. The metformin treatment also increases complete pathological tumour response rates following neoadjuvant chemotherapy for breast cancer, suggesting a potential role as an anti-cancer drug. Diabetes mellitus type 2 is associated with insulin resistance, elevated insulin levels and an increased risk of cancer and cancer-related mortality. This increased risk may be explained by activation of the insulin- and insulin-like growth factor (IGF) signalling pathways and increased signalling through the oestrogen receptor. Reversal of these processes through reduction of insulin resistance by the oral anti-diabetic drug metformin is an attractive anti-cancer strategy. Metformin is an activator of AMP-activated protein kinase (AMPK) which inhibits protein synthesis and gluconeogenesis during cellular stress. The main downstream effect of AMPK activation is the inhibition of mammalian target of rapamycin (mTOR), a downstream effector of growth factor signalling. mTOR is frequently activated in malignant cells and is associated with resistance to anticancer drugs. Furthermore, metformin can induce cell cycle arrest and apoptosis and can reduce growth factor signalling. This review discusses the role of diabetes mellitus type 2 and insulin resistance in carcinogenesis, the preclinical rationale and potential mechanisms of metformin's anti-cancer effect and the current and future clinical developments of metformin as a novel anti-cancer drug. (C) 2010 Elsevier Ltd. All rights reserved.

OBJECTIVE Type 2 diabetes and insulin resistance have been associated with mitochondrial dysfunction, but it is debated whether this is a primary factor in the pathogenesis of the disease. To test the concept that mitochondrial dysfunction is secondary to the development of insulin resistance, we employed the unique model of prolonged fasting in humans. Prolonged fasting is a physiologic condition in which muscular insulin resistance develops in the presence of increased free fatty acid (FFA) levels, increased fat oxidation and low glucose and insulin levels. It is therefore anticipated that skeletal muscle mitochondrial function is maintained to accommodate increased fat oxidation unless factors secondary to insulin resistance exert negative effects on mitochondrial function. RESEARCH DESIGN AND METHODS While in a respiration chamber, twelve healthy males were subjected to a 60 h fast and a 60 h normal fed condition in a randomized crossover design. Afterward, insulin sensitivity was assessed using a hyperinsulinemic-euglycemic clamp, and mitochondrial function was quantified ex vivo in permeabilized muscle fibers using high-resolution respirometry. RESULTS Indeed, FFA levels were increased approximately ninefold after 60 h of fasting in healthy male subjects, leading to elevated intramuscular lipid levels and decreased muscular insulin sensitivity. Despite an increase in whole-body fat oxidation, we observed an overall reduction in both coupled state 3 respiration and maximally uncoupled respiration in permeabilized skeletal muscle fibers, which could not be explained by changes in mitochondrial density. CONCLUSIONS These findings confirm that the insulin-resistant state has secondary negative effects on mitochondrial function. Given the low insulin and glucose levels after prolonged fasting, hyperglycemia and insulin action per se can be excluded as underlying mechanisms, pointing toward elevated plasma FFA and/or intramuscular fat accumulation as possible causes for the observed reduction in mitochondrial capacity.

Mitochondrial dysfunction in skeletal muscle has been suggested to underlie the development of insulin resistance and type 2 diabetes mellitus. Reduced mitochondrial capacity will contribute to the accumulation of lipid intermediates, desensitizing insulin signaling and leading to insulin resistance. Why mitochondrial function is reduced in the (pre-)diabetic state is, however, so far unknown. Although it is tempting to suggest that skeletal muscle insulin resistance may result from an inherited or acquired reduction in mitochondrial function in the pre-diabetic state, it can not be excluded that mitochondrial dysfunction may in fact be the consequence of the insulin-resistant/diabetic state. Lipotoxicity, the deleterious effects of accumulating fatty acids in skeletal muscle cells, may lie at the basis of mitochondrial dysfunction: next to producing energy, mitochondria are also the major source of reactive oxygen species (ROS). Fatty acids accumulating in the vicinity of mitochondria are vulnerable to ROS-induced lipid peroxidation. Subsequently, these lipid peroxides could have lipotoxic effects on mtDNA, RNA and proteins of the mitochondrial machinery, leading to mitochondrial dysfunction. Indeed, increased lipid peroxidation has been reported in insulin resistant skeletal muscle and the mitochondrial uncoupling protein-3, which has been suggested to prevent lipid-induced mitochondrial damage, is reduced in subjects with an impaired glucose tolerance and in type 2 diabetic patients. These findings support the hypothesis that fat accumulation in skeletal muscle may precede the reduction in mitochondrial function that is observed in type 2 diabetes mellitus.

Purpose of the review To describe the role of albuminuria as a risk marker for heart failure and a predictor for treatment effect on heart failure prognosis. Recent findings The level of albumin in the urine is a predictor of heart failure in the general population and in patients with cardiovascular risk, such as those with diabetes. Mild elevations of albuminuria, in the microalbuminuria range, appear to be associated with impaired systemic endothelial function. This increases the chance of developing hypertension, diabetes and cardiovascular disease, ultimately leading to heart failure. Higher levels of albuminuria, in the proteinuric range, reflect marked renal pathology, which increases cardiovascular risk due to renal function decline. In patients with established heart failure, microalbuminuria is highly prevalent (30%). Although more frequent in diastolic than systolic dysfunction, it appears to indicate a worse prognosis in the latter class. Diabetes is a multiplier of risk, probably due to bidirectional relationship between diabetes and heart failure. Treatment with drugs that intervene in the renin-angiotensin-alclosterone system (RAAS) lowers albuminuria and is associated with prevention of the onset and worsening of heart failure and other cardiovascular disorders. Summary Albuminuria is associated with increased heart failure risk. Lowering of albuminuria using RAAS inhibitors appears to lower the risk for heart failure.

Purpose of the reviewTo describe the role of albuminuria as a risk marker for heart failure and a predictor for treatment effect on heart failure prognosis.Recent findingsThe level of albumin in the urine is a predictor of heart failure in the general population and in patients with cardiovascular risk, such as those with diabetes. Mild elevations of albuminuria, in the microalbuminuria range, appear to be associated with impaired systemic endothelial function. This increases the chance of developing hypertension, diabetes and cardiovascular disease, ultimately leading to heart failure. Higher levels of albuminuria, in the proteinuric range, reflect marked renal pathology, which increases cardiovascular risk due to renal function decline. In patients with established heart failure, microalbuminuria is highly prevalent (30%). Although more frequent in diastolic than systolic dysfunction, it appears to indicate a worse prognosis in the latter class. Diabetes is a multiplier of risk, probably due to bidirectional relationship between diabetes and heart failure. Treatment with drugs that intervene in the renin-angiotensin-alclosterone system (RAAS) lowers albuminuria and is associated with prevention of the onset and worsening of heart failure and other cardiovascular disorders.SummaryAlbuminuria is associated with increased heart failure risk. Lowering of albuminuria using RAAS inhibitors appears to lower the risk for heart failure.

Atherosclerosis is the main contributor to cardiovascular disease and leads to intimal plaque formation, which may progress to plaque rupture with subsequent thromboembolic events and/or occlusion of the arterial lumen. There is increasing evidence that the development or progression of atherosclerosis is associated with advanced glycation endproducts (AGEs). AGEs are a heterogeneous group of compounds formed by the non-enzymatic reaction of reducing sugars with proteins, lipids, and nucleic acids. An increased understanding of the mechanisms of formation and interaction of AGEs has allowed the development of several potential anti-AGE strategies. This review summarizes AGE. formation and biochemistry, the pathogeneic role of AGEs in cardiovascular disease, anti-AGE therapies and clinical relevance to vascular surgery. (C) 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

induced fibronectin and transforming growth factor-beta1 production in human mesangial cells is p38 mitogen-activated protein kinase-dependent. Diabetes 2000; 49: 655–661 20. Cortes P, Mendez M, Riser BL et al. F-actin fiber distribution in glomerular cells: structural and functional implications. Kidney Int 2000; 58: 2452–2461 21. Burt DJ, Gruden G, Thomas SM et al. P38 mitogen-activated protein kinase mediates hexosamine-induced TGFbeta1 mRNA expression in human mesangial cells. Diabetologia 2003; 46: 531–537 22. King GL, Kunisaki M, Nishio Y, Inoguchi T, Shiba T, Xia P. Biochemical and molecular mechanisms in the development of diabetic vascular complications (Review). Diabetes 1996; 45 [Suppl 3]: S105–8 23. Inoki K, Haneda M, Maeda S, Koya D, Kikkawa R. TGF-beta 1 stimulates glucose uptake by enhancing GLUT1 expression in mesangial cells. Kidney Int 1999; 55: 1704–1712 24. Heilig CW, Liu Y, England RL et al. D-glucose stimulates mesangial cell Glut1 expression and basal and IGF-I-sensitive glucose uptake in rat mesangial cell. Diabetes 1997; 46: 1030–1039 25. Heilig CW, Concepcion LA, Riser BL, Freytag SO, Zhu M, Cortes P. Overexpression of glucose transporters in rat mesangial cells cultured in a normal glucose milieu mimics the diabetic phenotype. J Clin Invest 1995; 96: 1802–1814 26. Heilig CW, Kreisberg JI, Freytag S et al. Antisense GLUT-1 protects mesangial cells from glucose induction of GLUT-1 and fibronectin expression. Am J Physiol Renal Physiol 2001; 280: F657–F666 27. Chen S, Heilig KO, Brosius FC,III, Heilig CW. Diabetes increases glomerular Glut1, and antisense-Glut1 protects against diabetic glomerulosclerosis (Abstract). J Am Soc Nephrol 2003; 14: 46A 28. Heilig KO, Chen S, Xiang M, Brosius FC, Heilig CW. Transgenic overexpression of Glut1 in glomeruli produces feature of diabetic nephropathy in mice (Abstract). J Am Soc Nephrol 2004; 15: 263A 29. Zintzaras E, Stefanidis I. Association between the GLUT1 gene polymorphism and the risk of diabetic nephropathy: a meta-analysis. J Hum Genet 2005; 50: 84–91

Excretion of albumin in the urine is highly variable, ranging from nondetectable quantities to milligrams of albumin and even grams of albumin. Microalbuminuria is defined as low levels of urinary albumin excretion of 30 to 300 mg/d. Microalbuminuria is highly prevalent; in hypertensive and diabetic populations, its prevalence varies from 10 to 40%. It is interesting that microalbuminuria also is found frequently in seemingly healthy individuals (5 to 7%). The variable excretion of albumin in the urine is related to the risk for the individual to develop cardiovascular (CV) disease: Absence or very low levels of albuminuria is associated with low CV risk, whereas the CV risk increases markedly with increasing amount of albumin in the urine (even within the now considered normal range). The predictive power of urinary albumin levels for CV risk is independent of other CV risk factors and not only is present in individual with diabetes and/or hypertension but also in healthy individuals. Treatments that lower albuminuria are associated with CV protection, as demonstrated in randomized, controlled trials of patients with diabetes as well as in patients with hypertension. There is preliminary evidence that albuminuria lowering is CV protective in healthy individuals with an elevated albumin excretion rate. Differences between individuals in their level of albumin excretion are already observed at a very early age (just after birth). In fact, the interindividual variability seems to be relatively constant in the first 5 decades of life, indicating that microalbuminuria is not necessarily a consequence of vascular damage at later age. Higher levels of urinary albumin seem to reflect the ordinary interindividual variability in (renal and systemic) endothelial function. Experimental data show that between strains and even within strains, rats at young age show a remarkable difference in individual endothelial function, and this is strongly related to the susceptibility of that rat to organ damage. In conclusion, albuminuria seems to be a sensitive marker very early in life for the susceptibility of an individual to CV disease. It therefore may be an ideal target for early primary prevention using CV-protective therapy regimens.

Impaired endothelial function is recognised as one of the earliest events of atherogenesis. Endothelium-dependent vasomotion has been the principal method to assess endothelial function. In this article, we will discuss the clinical value of the different techniques to evaluate endothelium-dependent vasomotion. To date, there seems not to be a simple and reliably endothelial function test to identify asymptomatic subjects at increased risk for cardiovascular disease in clinical practice. Recent studies indicate that pharmacological interventions, in particular with ACE-inhibitors and statins, might improve endothelial function. However, there is no solid evidence that improvement of endothelial function is a necessity for the observed reduction in cardiovascular events by these compounds. Overall, at this moment, there is no place in clinical practice for the use of endothelial function as a method for risk assessment or target of pharmacological interventions. (c) 2005 Elsevier Inc. All rights reserved.

CONTEXT: Obesity and type 2 diabetes mellitus are associated with increased levels of IL-6, a marker of inflammation. OBJECTIVE: This study addressed the question of whether IL-6 was released from skeletal muscle after a high-fat meal in men with impaired glucose tolerance (IGT), a prediabetic state, and whether IL-6 release could be reduced by weight loss. DESIGN: Skeletal muscle metabolism was studied in men with IGT (n = 11) and compared with men with normal glucose tolerance (NGT, n = 9), matched for body mass index and age. IL-6 flux over skeletal muscle was measured with the forearm model. Eight IGT men were willing to participate in a 12-wk weight loss program and were tested again. RESULTS: IL-6, but not C-reactive protein or TNF-alpha receptor 1 and 2, was released by skeletal muscle. Muscle IL-6 release was higher in IGT than in NGT during fasting (IGT = 2.26 +/- 1.89 vs. NGT = 0.87 +/- 0.48 fmol x 100 ml tissue(-1) x min(-1), P = 0.04) and after a meal (mean area under the curve per minute: IGT = 3.48 +/- 2.63 vs. NGT = 1.37 +/- 0.75 fmol x 100 ml tissue(-1) x min(-1); P = 0.03). In the IGT men, body weight loss resulted in a decrease of postprandial IL-6 release from skeletal muscle (-52%; P = 0.04), reaching levels of the obese, NGT controls. CONCLUSION: The present data suggest that a high-fat meal can evoke IL-6 release from muscle and that the IL-6 release is a consequence rather than a cause of the obese, insulin-resistant, and/or IGT state.

Several current diseases are associated with an increase in the oxidation of HDL, which is likely to impair their functionality. Our aim was to identify whether oxidation could change the protective effect of HDL against the deleterious effect on vasoreactivity induced by oxidative stress. HDL from healthy subjects were oxidized in vitro by Cu2+, and the ability of oxidized HDL to counteract the inhibitory effect of oxidized LDL on acetylcholine-induced vasodilation was tested on isolated rabbit aorta rings. Oxidation of HDL was evidenced by the increase in the 7-oxysterols/cholesterol ratio (3.20 +/- A 1.12 vs 0.02 +/- A 0.01 % in native HDL, p < 0.05). Oxidized LDL inhibited endothelium-dependent vasodilation (E (max) = 50.2 +/- A 5.0 vs 92.5 +/- A 1.7 % for incubation in Kreb's buffer, p < 0.05) and native HDL counteracted this inhibition (E (max) = 72.4 +/- A 4.8 vs 50.2 +/- A 5.0 % p < 0.05). At the opposite, oxidized HDL had no effect on oxidized LDL-induced inhibition on endothelium-dependent vasorelaxation (E (max) = 53.7 +/- A 4.8 vs 50.2 +/- A 5.0 %, NS). HDL oxidation is associated with a decreased ability of HDL to remove 7-oxysterols from oxidized LDL. In conclusion, these results show that oxidation of HDL induces the loss of their protective effect against endothelial dysfunction, which could promote atherosclerosis in diseases associated with increased oxidative stress.

AIMS Sulodexide is a highly purified mixture of glycosaminoglycans that has been studied for its anti-albuminuric potential. Considering the effects of glycosaminoglycans on endothelial function and sodium homeostasis, we hypothesized that sulodexide may lower blood pressure (BP). In this meta-analysis, we therefore investigated the antihypertensive effects of sulodexide treatment. METHODS We selected randomized controlled trials that investigated sulodexide treatment of at least 4 weeks and measured BP at baseline and after treatment. Two reviewers independently extracted data on study design, risk of bias, population characteristics and outcome measures. In addition, we contacted authors and pharmaceutical companies to provide missing data. RESULTS Eight studies, totalling 3019 subjects (mean follow-up 4.4 months) were included. Mean age was 61 years and mean baseline BP was 135/75 mmHg. Compared with control treatment, sulodexide resulted in a significant systolic (2.2 mmHg [95% CI 0.3, 4.1], P = 0.02) and diastolic BP reduction (1.7 mmHg [95% CI 0.6, 2.9], P = 0.004). Hypertensive patients displayed the largest systolic BP and diastolic BP reductions (10.2/5.4 mmHg, P

Recent preclinical studies showed the potential of nicotinamide adenine dinucleotide (NAD+) precursors to increase oxidative phosphorylation and improve metabolic health, but human data are lacking. We hypothesize that the nicotinic acid derivative acipimox, an NAD+ precursor, would directly affect mitochondrial function independent of reductions in nonesterified fatty acid (NEFA) concentrations. In a multicenter randomized crossover trial, 21 patients with type 2 diabetes (age 57.7 ± 1.1 years, BMI 33.4 ± 0.8 kg/m2) received either placebo or acipimox 250 mg three times daily dosage for 2 weeks. Acipimox treatment increased plasma NEFA levels (759 ± 44 vs. 1,135 ± 97 μmol/L for placebo vs. acipimox, P < 0.01) owing to a previously described rebound effect. As a result, skeletal muscle lipid content increased and insulin sensitivity decreased. Despite the elevated plasma NEFA levels, ex vivo mitochondrial respiration in skeletal muscle increased. Subsequently, we showed that acipimox treatment resulted in a robust elevation in expression of nuclear-encoded mitochondrial gene sets and a mitonuclear protein imbalance, which may indicate activation of the mitochondrial unfolded protein response. Further studies in C2C12 myotubes confirmed a direct effect of acipimox on NAD+ levels, mitonuclear protein imbalance, and mitochondrial oxidative capacity. To the best of our knowledge, this study is the first to demonstrate that NAD+ boosters can also directly affect skeletal muscle mitochondrial function in humans.

BACKGROUND & AIMS: The incretins glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are gastrointestinal peptide hormones regulating postprandial insulin release from pancreatic β-cells. GLP-1 agonism is a treatment strategy in Type 2 diabetes and is evaluated in Non-alcoholic fatty liver disease (NAFLD). However, the role of incretins in its pathophysiology is insufficiently understood. Studies in mice suggest improvement of hepatic steatosis by GLP-1 agonism. We determined the secretion of incretins after oral glucose administration in non-diabetic NAFLD patients. METHODS: N=52 patients (n=16 NAFLD and n=36 Non-alcoholic steatohepatitis (NASH) patients) and n=50 matched healthy controls were included. Standardized oral glucose tolerance test was performed. Glucose, insulin, glucagon, GLP-1 and GIP plasma levels were measured sequentially for 120 minutes after glucose administration. RESULTS: Glucose induced GLP-1 secretion was significantly decreased in patients compared to controls (p

The role of peroxisome proliferator-activated receptor d (PPARd) activation on global gene expression and mitochondrial fuel utilization were investigated in human myotubes. Only 21 genes were up-regulated and 3 genes were down-regulated after activation by the PPARd agonist GW501516. Pathway analysis showed up-regulated mitochondrial fatty acid oxidation, TCA cycle and cholesterol biosynthesis. GW501516 increased oleic acid oxidation and mitochondrial oxidative capacity by 2-fold. Glucose uptake and oxidation were reduced, but total substrate oxidation was not affected, indicating a fuel switch from glucose to fatty acid. Cholesterol biosynthesis was increased, but lipid biosynthesis and mitochondrial content were not affected. This study confirmed that the principal effect of PPARd activation was to increase mitochondrial fatty acid oxidative capacity. Our results further suggest that PPARd activation reduced glucose utilization through a switch in mitochondrial substrate preference by up-regulating pyruvate dehydrogenase kinase isozyme 4 and genes involved in lipid metabolism and fatty acid oxidation.

Background The hypocholesterolemic effect of plant stanol ester consumption has been studied extensively, but its effect on cardiovascular health has been less frequently investigated. We studied the effects of plant stanol esters (staest) on arterial stiffness and endothelial function in adults without lipid medication. Methods Ninety-two asymptomatic subjects, 35 men and 57 women, mean age of 50.8±1.0 years (SEM) were recruited from different commercial companies. It was randomized, controlled, double-blind, parallel trial and lasted 6 months. The staest group (n=46) consumed rapeseed oil-based spread enriched with staest (3.0 g of plant stanols/d), and controls (n=46) the same spread without staest. Arterial stiffness was assessed via the cardio-ankle vascular index (CAVI) in large and as an augmentation index (AI) in peripheral arteries, and endothelial function as reactive hyperemia index (RHI). Lipids and vascular endpoints were tested using analysis of variance for repeated measurements. Results At baseline, 28% of subjects had a normal LDL cholesterol level (≤3.0 mmol/l) and normal arterial stiffness (

Background: Obesity and type 2 diabetes are associated with impaired skeletal muscle mitochondrial metabolism. As an intrinsic characteristic of an individual, skeletal muscle mitochondrial dysfunction could be a risk factor for weight gain and obesity-associated co-morbidities, such as type 2 diabetes. On the other hand, impaired skeletal muscle metabolism could be a consequence of obesity. We hypothesize that marked weight loss after bariatric surgery recovers skeletal muscle mitochondrial function.Methods: Skeletal muscle mitochondrial function as assessed by high-resolution respirometry was measured in 8 morbidly obese patients (body mass index [BMI], 41.3 +/- 4.7 kg/m(2); body fat, 48.3% +/- 5.2%) before and 1 year after bariatric surgery (mean weight loss: 35.0 +/- 8.6 kg). The results were compared with a lean (BMI 22.8 +/- 1.1 kg/m(2); body fat, 15.6% +/- 4.7%) and obese (BMI 33.5 +/- 4.2 kg/m(2); body fat, 34.1% +/- 6.3%) control group.Results: Before surgery, adenosine diphosphate (ADP)-stimulated (state 3) respiration on glutamate/succinate was decreased compared with lean patients (9.5 +/- 2.4 versus 15.6 +/- 4.4 O-2 flux/mtDNA; P Conclusion: We conclude that impaired skeletal muscle mitochondrial function is a consequence of obesity that recovers after marked weight loss. (Surg Obes Relat Dis 2013;9:936-941.)

Background Resilience or the ability of our body to cope with daily-life challenges has been proposed as a new definition of health, with restoration of homeostasis as target resultant of various physiological stress responses. Challenge models may thus be a sensitive measure to study the body’s health. The objective of this study was to select a dietary challenge model for the assessment of inflammatory resilience. Meals are a challenge to metabolic homeostasis and are suggested to affect inflammatory pathways, yet data in literature are limited and inconsistent. Method The kinetic responses of three different dietary challenges and a water control challenge were assessed on various metabolic and inflammatory markers in 14 healthy males and females using a full cross-over study design. The dietary challenges included glucose (75 g glucose in 300 ml water), lipids (200 ml whipping cream) and a mix of glucose and lipids (same amounts as above), respectively. Blood samples were collected at baseline and at 0.5, 1, 2, 4, 6, 8 and 10 h after consumption of the treatment products. Inflammation (IFNγ, IL-1β, IL-6, IL-8, IL-10, IL-12p70, TNF-α CRP, ICAM-1, VCAM-1, SAA, E-selectin, P-selectin, thrombomodulin, leukocytes, neutrophils, lymphocytes) and clinical (e.g. glucose, insulin, triglycerides) markers as well as gene expression in blood cells and plasma oxylipin profiles were measured. Results All three dietary challenges induced changes related to metabolic control such as increases in glucose and insulin after the glucose challenge and increases in triglycerides after the lipid challenge. In addition, differences between the challenges were observed for precursor oxylipins and some downstream metabolites including DiHETrE’s and HODE’s. However, none of the dietary challenges induced an acute inflammatory response, except for a modest increase in circulating leukocyte numbers after the glucose and mix challenges. Furthermore, subtle, yet statistically significant increases in vascular inflammatory markers (sICAM-1 and sVCAM-1) were found after the mix challenge, when compared to the water control challenge. Conclusions This study shows that dietary glucose and lipid challenges did not induce a strong acute inflammatory response in healthy subjects, as quantified by an accurate and broad panel of parameters.

Item does not contain fulltext OBJECTIVE: This study aims to determine the effect of pregnancy on the accuracy of 3 commonly used methods to estimate glomerular filtration rate ([GFR] creatinine clearance, the Cockroft-Gault, and modification of diet in renal disease [MDRD] formulas) using the inulin clearance as a reference. DESIGN: Longitudinal study design. SETTING: University hospital. Population: A total of 44 parous nonsmoking Caucasian women. They had a history of uneventful pregnancy (n = 9), preeclampsia (n = 27), and intrauterine fetal demise (n = 8). METHODS: Measurements were performed both in pre-pregnancy and early pregnancy (8 weeks of gestation) and included inulin infusion, blood pressure, and 24-hour urinary and serum creatinine. Agreement between methods to estimate GFR was assessed by the Bland and Altman method. Main outcome measures: GFR estimated by inulin and creatinine clearances and the Cockroft-Gault and MDRD formulas. RESULTS: During early pregnancy, the GFR measured by inulin increased 32% compared with the pre-pregnant value (from 115 +/- 18 to 150 +/- 23 mL/min.1.73 m(-2)), whilst the GFR measured by the indirect methods only increased 20%. The observed bias and limits of agreements are larger in early pregnancy relative to the pre-pregnant state for all 3 methods. CONCLUSION: The renal hyperfiltration during pregnancy decreases further the accuracy of the creatinine clearance and the Cockroft-Gault and MDRD formulas to estimate GFR.

Background:Several epidemiological studies revealed sex-specific differences during oral glucose tolerance tests (OGTTs), such as higher prevalence of glucose intolerance (i.e. increased glucose at the end of the OGTT) in females, which was not yet explained. Thus, we aimed to analyze sex-related distinctions on OGTT glucose metabolism, including gut absorption, in healthy humans.Methods:Females (n = 48) and males (n = 26) with comparable age (females, 45 ± 1 yr; males, 44 ± 2 yr) and body mass index (both, 25 ± 1 kg/m2) but different height (females, 166 ± 1 cm; males, 180 ± 2 cm; P < 0.000001), all normally glucose tolerant, as tested by frequently sampled, 3-h (75-g) OGTTs, underwent hyperinsulinemic [40 mU/(min · m2)] isoglycemic clamp tests with simultaneous measurement of endogenous glucose (d-[6,6-2H2]glucose) production (EGP). EGP and glucose disappearance during OGTT were calculated from logarithmic relationships with clamp test insulin concentrations. After reliable model validation by double-tracer technique (r = 0.732; P < 0.007), we calculated and modeled gut glucose absorption (ABS).Results:Females showed lower (P < 0.05) fasting EGP [1.4 ± 0.1 mg/(kg · min)] than males [1.7 ± 0.1 mg/(kg · min)] but comparable whole-body insulin sensitivity in clamp tests [females, 8.1 ± 0.4 mg/(kg · min); males, 8.3 ± 0.6 mg/(kg · min)]. Plasma glucose OGTT concentrations were higher (P < 0.04) from 30–40 min in males but from 120–180 min in females. Glucose absorption rates were 21–46% increased in the initial 40 min in males but in females by 27–40% in the third hour (P < 0.05). Gut glucose half-life was markedly higher in females (79 ± 2 min) than in males (65 ± 3 min, P < 0.0001) and negatively related to body height (r = −0.481; P < 0.0001).Conclusions:This study in healthy, glucose-tolerant humans shows for the first time different ABS rates during OGTT in women and men and a negative relationship between body height and gut glucose half-life. Prolonged ABS in females might therefore contribute to higher plasma glucose concentrations at the end of OGTT.

Metformin is widely used in the treatment of diabetes mellitus type 2 where it reduces insulin resistance and diabetes-related morbidity and mortality. Population-based studies show that metformin treatment is associated with a dose-dependent reduction in cancer risk. The metformin treatment also increases complete pathological tumour response rates following neoadjuvant chemotherapy for breast cancer, suggesting a potential role as an anti-cancer drug. Diabetes mellitus type 2 is associated with insulin resistance, elevated insulin levels and an increased risk of cancer and cancer-related mortality. This increased risk may be explained by activation of the insulin- and insulin-like growth factor (IGF) signalling pathways and increased signalling through the oestrogen receptor. Reversal of these processes through reduction of insulin resistance by the oral anti-diabetic drug metformin is an attractive anti-cancer strategy. Metformin is an activator of AMP-activated protein kinase (AMPK) which inhibits protein synthesis and gluconeogenesis during cellular stress. The main downstream effect of AMPK activation is the inhibition of mammalian target of rapamycin (mTOR), a downstream effector of growth factor signalling. mTOR is frequently activated in malignant cells and is associated with resistance to anticancer drugs. Furthermore, metformin can induce cell cycle arrest and apoptosis and can reduce growth factor signalling. This review discusses the role of diabetes mellitus type 2 and insulin resistance in carcinogenesis, the preclinical rationale and potential mechanisms of metformin's anti-cancer effect and the current and future clinical developments of metformin as a novel anti-cancer drug. (C) 2010 Elsevier Ltd. All rights reserved.

Background:The impaired glucose tolerance (IGT) state is characterized by insulin resistance. Disturbances in fatty acid (FA) metabolism may underlie this reduced insulin sensitivity. The aim of this study was to investigate whether the prediabetic state is accompanied by changes in the expression of genes involved in FA handling during fasting and in insulin-mediated conditions and to study the impact of weight loss. Methods:Seven IGT men and 5 men with normal glucose tolerance (NGT), comparable in terms of age and BMI, participated in the study. The 5 IGT men followed a 12-week weight loss program. Muscle biopsies were taken and the expression of 6 genes was investigated. Results:Subjects had a reduction of 15.5 ± 4.3 kg in body weight. Baseline gene expression was not different between NGT and IGT men. After a hyperinsulinemic clamp, there was an overall upregulation of PGC1α, SREBP-1c, SREBP-2, and ACC-2. The upregulation of SREBP-2 was more pronounced in IGT men (p = 0.049). Weight loss significantly increased insulin sensitivity by 71%, which was not reflected in altered gene expression profiles. Conclusions:SREBP-2 shows altered insulin responsiveness in IGT men compared with NGT men, while there were no differences in basal gene expression.

International audience; BACKGROUND: Transcription factor 7-like 2 (TCF7L2) rs7903146 associates with type 2 diabetes and may operate via impaired glucagon-like peptide 1 secretion, which is stimulated more by fat than by carbohydrate ingestion. OBJECTIVE: The objective was to examine the interaction between TCF7L2 rs7903146 and dietary fat and carbohydrate [high-fat, low-carbohydrate: 40-45% of energy as fat (HF); compared with low-fat, high-carbohydrate: 20-25% of energy as fat (LF)] in obese individuals' responses to a 10-wk hypoenergetic diet (-600 kcal/d). DESIGN: European, obese participants (n = 771) were randomly assigned to receive an HF or an LF diet. Body weight, fat mass (FM), fat-free mass (FFM), waist circumference (WC), resting energy expenditure (REE), fasting fat oxidation in percentage of REE (FatOx), homeostasis model assessed insulin release (HOMA-beta), and HOMA-insulin resistance (HOMA-IR) were determined at baseline and after the intervention; 739 individuals were genotyped for rs7903146. RESULTS: Average weight loss was 6.9 kg with the LF and 6.6 kg with the HF (difference between diets, NS) diet. Among individuals who were homozygous for the T-risk allele, those in the HF diet group experienced smaller weight losses (Deltaweight) (2.6 kg; P = 0.009; n = 622), smaller DeltaFFM (1.6 kg; P = 0.027; n = 609), smaller DeltaWC (3.3 cm; P = 0.010; n = 608), and a smaller DeltaHOMA-IR (1.3 units; P = 0.004; n = 615) than did the LF diet group. For C allele carriers, there were no differences between the HF and LF diet groups. For the HF diet group, each additional T allele was associated with a reduced loss of FM (0.67 kg; P = 0.019; n = 609). TCF7L2 rs7903146 was not associated with DeltaREE, DeltaFatOx, DeltaHOMA-beta, or dropout. CONCLUSION: Our results suggest that obese individuals who are homozygous for the TCF7L2 rs7903146 T-risk allele are more sensitive to LF than to HF weight-loss diets.

Background Due to the increasing importance of identifying insulin resistance, a need exists to have a reliable mathematical model representing the glucose/insulin control system. Such a model should be simple enough to allow precise estimation of insulin sensitivity on a single patient, yet exhibit stable dynamics and reproduce accepted physiological behavior. Results A new, discrete Single Delay Model (SDM) of the glucose/insulin system is proposed, applicable to Intra-Venous Glucose Tolerance Tests (IVGTTs) as well as to multiple injection and infusion schemes, which is fitted to both glucose and insulin observations simultaneously. The SDM is stable around baseline equilibrium values and has positive bounded solutions at all times. Applying a similar definition as for the Minimal Model (MM) SI index, insulin sensitivity is directly represented by the free parameter KxgI of the SDM. In order to assess the reliability of Insulin Sensitivity determinations, both SDM and MM have been fitted to 40 IVGTTs from healthy volunteers. Precision of all parameter estimates is better with the SDM: 40 out of 40 subjects showed identifiable (CV < 52%) KxgI from the SDM, 20 out of 40 having identifiable SI from the MM. KxgI correlates well with the inverse of the HOMA-IR index, while SI correlates only when excluding five subjects with extreme SI values. With the exception of these five subjects, the SDM and MM derived indices correlate very well (r = 0.93). Conclusion The SDM is theoretically sound and practically robust, and can routinely be considered for the determination of insulin sensitivity from the IVGTT. Free software for estimating the SDM parameters is available.