Therapeutic lifestyle change intervention improved metabolic syndrome criteria and is complementary to amlodipine/atorvastatin.

AIMS: To examine whether addition of amlodipine (5 mg)/atorvastatin (10 mg) A/A to Therapeutic Lifestyle change intervention (TLC) would beneficially modulate Metabolic Syndrome (MetS) and oxidized low-density lipoprotein (Ox-LDL) levels. METHODS: Patients with MetS (n = 53) were randomized to TLC + placebo or TLC + A/A for 12 months. Anthropometric measurements, blood pressure (BP), lipid profile, plasma Ox-LDL, and area under the curve of free fatty acid (AUCFFA) during oral glucose tolerance test, a marker of adipose tissue health, were assessed before and after the intervention. RESULTS: Twenty-six patients completed the study with an overall improvement of MetS (p = 0.02). TLC + placebo was beneficial in reversing MetS comparable to TLC + A/A (54% vs. 39%; p = 0.08). Both treatments decreased systolic BP (p ≤ 0.01). TLC + A/A also decreased diastolic BP and triglyceride levels. The changes in Ox-LDL levels directly correlated with changes in weight in the TLC-placebo group (r = 0.64; p = 0.04). AUCFFA determined the loss of fat mass (r = 0.472, p = 0.03). CONCLUSIONS: 1) Addition of A/A has the advantage of improving the lipid profile and BP; but TLC alone was comparable to TLC + A/A in improving MetS; 2) weight change determines the TLC-associated change in Ox-LDL levels; and 3) AT metabolic health is a significant predictor of TLC-associated loss of body fat mass.

Amelioration of hippocampal dysfunction by adipose tissue-targeted stem cell transplantation in a mouse model of type 2 diabetes.

There is growing evidence that type 2 diabetes or insulin resistance is linked to cognitive impairment. We recently confirmed altered lipid composition, down-regulation of insulin receptor expression and impaired basal synaptic transmission in the hippocampus of our transgenic murine model of adipocyte insulin resistance (AtENPP1-Tg). Here we evaluated whether the correction of adipose tissue dysfunction [via the subcutaneous transplantation of mesenchymal stem cells (MSC)] can improve the hippocampal synaptic transmission in AtENPP1-Tg mice versus their wildtype littermates. Animals were simply randomized to receive MSC, then weighed weekly for 12 weeks. At euthanasia, we assessed leptin in the collected serum and hippocampal synaptic high-frequency stimulation long-term potentiation (HFS-LTP) using brain slices. MSC transplantation normalized AtENPP1-Tg body and epididymal fat weights and was associated with increased leptin levels, a sign of adipocyte maturation. More importantly, transplantation restored the deficiency observed in AtENPP1-Tg HFS-LTP, the cellular readout of memory. Our results further corroborate the role of adipocyte maturation arrest in adipose tissue and highlight a role for the adipose tissue in modulating hippocampal cellular mechanisms. Further studies are warranted to explore the mechanisms for the MSC-induced improvement of hippocampal HFS-LTP.

Effect of high-fat diet on peripheral blood mononuclear cells and adipose tissue in early stages of diet-induced weight gain.

Subcutaneous adipose tissue (scAT) and peripheral blood mononuclear cells (PBMC) play a significant role in obesity-associated systemic low-grade inflammation. High-fat diet (HFD) is known to induce inflammatory changes in both scAT and PBMC. However, the time course of the effect of HFD on these systems is still unknown. The aim of the present study was to determine the time course of the effect of HFD on PBMC and scAT. New Zealand white rabbits were fed HFD for 5 or 10 weeks (i.e. HFD-5 and HFD-10) or regular chow (i.e. control (CNT)-5 and CNT-10). Thereafter, metabolic and inflammatory parameters of PBMC and scAT were quantified. HFD induced hyperfattyacidaemia in HFD-5 and HFD-10 groups, with the development of insulin resistance in HFD-10, while no changes were observed in scAT lipid metabolism and inflammatory status. HFD activated the inflammatory pathways in PBMC of HFD-5 group and induced modified autophagy in that of HFD-10. The rate of fat oxidation in PBMC was directly associated with the expression of inflammatory markers and tended to inversely associate with autophagosome formation markers in PBMC. HFD affected systemic substrate metabolism, and the metabolic, inflammatory and autophagy pathways in PBMC in the absence of metabolic and inflammatory changes in scAT. Dietary approaches or interventions to avert HFD-induced changes in PBMC could be essential to prevent metabolic and inflammatory complications of obesity and promote healthier living.

Quantification of muscle triglyceride synthesis rate requires an adjustment for total triglyceride content.

Intramyocellular triglyceride (imTG) in skeletal muscle plays a significant role in metabolic health, and an infusion of [13C16]palmitate can be used to quantitate the in vivo fractional synthesis rate (FSR) and absolute synthesis rate (ASR) of imTGs. However, the extramyocellular TG (emTG) pool, unless precisely excised, contaminates the imTG pool, diluting the imTG-bound tracer enrichment and leading to underestimation of FSR. Because of the difficulty of excising the emTGs precisely, it would be advantageous to be able to calculate the imTG synthesis rate without dissecting the emTGs from each sample. Here, we tested the hypothesis that the ASR of total TGs (tTGs), a combination of imTGs and emTGs, calculated as "FSR × tTG pool," reasonably represents the imTG synthesis. Muscle lipid parameters were measured in nine healthy women at 90 and 170 min after the start of [13C16]palmitate infusion. While the measurements of tTG content, enrichment, and FSR did not correlate (P > 0.05), those of the tTG ASR were significantly correlated (r = 0.947, P < 0.05). These results demonstrate that when imTGs and emTGs are pooled, the resulting underestimation of imTG FSR is balanced by the overestimation of the imTG content. We conclude that imTG metabolism is reflected by the measurement of the tTG ASR.

The Effect of Burn Trauma on Lipid and Glucose Metabolism: Implications for Insulin Sensitivity.

Severe burns represent a unique form of trauma in terms of the magnitude and persistence of the stress response they incur. Given advances in acute burn care in the last quarter of a century and the resultant reduction in mortality rates, even for those with massive burns, greater emphasis is now placed on understanding the metabolic stress response to severe burn trauma in order to devise strategies that promote recovery and reduce morbidity. Derangements in metabolism including protein and lipid redistribution and altered glucose handling are hallmarks of the pathophysiological response to burn trauma. In this review article, we aim to distill and discuss the c urrent literature concerning the effect of burn trauma on lipid and glucose metabolism. Furthermore, we will discuss the implications of altered lipid metabolism with regards to insulin sensitivity and glucose control, while discussing the utility of agents and strategies aimed at restoring normal lipid and glucose metabolism in burned patients.

Sex-dependent difference in the relationship between adipose-tissue cholesterol efflux and estradiol concentrations in young healthy humans.

BACKGROUND: Impaired adipose tissue function and lower levels of high density lipoprotein cholesterol (HDL-C) have been implicated in the development of vascular dementia, and metabolic diseases such as hypertension, atherosclerosis, type 2 diabetes (T2D) and metabolic syndrome. Interestingly, both the substrate fluxes in adipose tissue and HDL-C concentration differ between men and women. Moreover, adipose tissue cholesterol efflux has been implicated in modulation of HDL-C levels. Thus, we aimed to determine if the association between serum estradiol levels and adipose tissue cholesterol efflux is sex-dependent. METHOD: We evaluated the serum estradiol levels and adipose tissue cholesterol efflux in young healthy men (n=5) and women (n=3). Adipose tissue cholesterol efflux was determined using subcutaneous microdialysis probes. Linear regression analyses were used to determine the relationship between the parameters, p<0.05 was considered as statistically significant. RESULTS: Our data demonstrated that serum estradiol levels directly associated with adipose tissue cholesterol efflux; however, the relationships may be sex-dependent. We discussed our results in the context of currently available data regarding sex-dependent variability in adipose tissue function and HDL-C metabolism as a potential contributor to higher rates of vascular dementia in men. Further research is required to understand the sex-dependent and -independent variabilities in adipose tissue metabolism to determine novel targets for interventions to prevent the development of vascular dementia.

Current and future therapies for addressing the effects of inflammation on HDL cholesterol metabolism.

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. Inflammatory processes arising from metabolic abnormalities are known to precipitate the development of CVD. Several metabolic and inflammatory markers have been proposed for predicting the progression of CVD, including high density lipoprotein cholesterol (HDL-C). For ~50 years, HDL-C has been considered as the atheroprotective 'good' cholesterol because of its strong inverse association with the progression of CVD. Thus, interventions to increase the concentration of HDL-C have been successfully tested in animals; however, clinical trials were unable to confirm the cardiovascular benefits of pharmaceutical interventions aimed at increasing HDL-C levels. Based on these data, the significance of HDL-C in the prevention of CVD has been called into question. Fundamental in vitro and animal studies suggest that HDL-C functionality, rather than HDL-C concentration, is important for the CVD-preventive qualities of HDL-C. Our current review of the literature positively demonstrates the negative impact of systemic and tissue (i.e. adipose tissue) inflammation in the healthy metabolism and function of HDL-C. Our survey indicates that HDL-C may be a good marker of adipose tissue health, independently of its atheroprotective associations. We summarize the current findings on the use of anti-inflammatory drugs to either prevent HDL-C clearance or improve the function and production of HDL-C particles. It is evident that the therapeutic agents currently available may not provide the optimal strategy for altering HDL-C metabolism and function, and thus, further research is required to supplement this mechanistic approach for preventing the progression of CVD. LINKED ARTICLES: This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.

Risk of Obesity-Related Cardiometabolic Complications in Special Populations: A Crisis in Asians.

The prospect of a significant increase in global health-related costs associated with high cardiometabolic complications of obesity in Asians has encouraged more attention to be focused on the problem of growing obesity prevalence in these populations. Although these studies have shown that cardiometabolic complications occur more frequently and at a lower body mass index (BMI) in Asians than in European populations, the mechanisms involved have yet to be discovered. Ethnic/racial differences in body composition and fat distribution have been studied extensively. Although these studies have shown that increasing BMI is associated with larger increases in body fat content in Asians, growing evidence points to factors other than body fat content and fat distribution in determining a higher prevalence of cardiometabolic complications in these populations. Here, we provide support to our view that earlier onset of adipocyte maturation arrest/insulin resistance during weight gain could be a major factor in increasing the cardiometabolic risk of Asian populations at a lower BMI.

Adipose Tissue Insulin Resistance in Gestational Diabetes.

BACKGROUND: Gestational diabetes mellitus (GDM) is a metabolic disorder characterized by insulin resistance (IR) and altered glucose-lipid metabolism. We propose that ectonucleotide pyrophosphate phosphodiesterase-1 (ENPP1), a protein known to induce adipocyte IR, is a determinant of GDM. Our objective was to study ENPP1 expression in adipose tissue (AT) of obese pregnant women with or without GDM, as well as glucose tolerance in pregnant transgenic (Tg) mice with AT-specific overexpression of human ENPP1. METHODS: AT biopsies and blood were collected from body mass index-matched obese pregnant women non-GDM (n = 6), GDM (n = 7), and nonpregnant controls (n = 6) undergoing cesarian section or elective surgeries, respectively. We measured the following: (1) Expression of key molecules involved in insulin signaling and glucose-lipid metabolism in AT; (2) Plasma glucose and insulin levels and calculation of homeostasis model assessment of IR (HOMA-IR); (3) Intraperitoneal glucose tolerance test in AtENPP1 Tg pregnant mice. RESULTS: We found that: (1) Obese GDM patients have higher AT ENPP1 expression than obese non-GDM patients, or controls (P = 0.01-ANOVA). (2) ENPP1 expression level correlated negatively with glucose transporter 4 (GLUT4) and positively with insulin receptor substrate-1 (IRS-1) serine phosphorylation, and to other adipocyte functional proteins involved in glucose and lipid metabolism (P < 0.05 each), (3) AT ENPP1 expression levels were positively correlated with HOMA-IR (P = 0.01-ANOVA). (4) Pregnant AT ENPP1 Tg mice showed higher plasma glucose than wild type animals (P = 0.046-t test on area under curve [AUC]glucose). CONCLUSIONS: Our results provide evidence of a causative link between ENPP1 and alterations in insulin signaling, glucose uptake, and lipid metabolism in subcutaneous abdominal AT of GDM, which may mediate IR and hyperglycemia in GDM.

Palmitoyl-carnitine production by blood cells associates with the concentration of circulating acyl-carnitines in healthy overweight women.

BACKGROUND: Circulating acyl-carnitines (acyl-CNTs) are associated with insulin resistance (IR) and type 2 diabetes (T2D) in both rodents and humans. However, the mechanisms whereby circulating acyl-CNTs are increased in these conditions and their role in whole-body metabolism remains unknown. The purpose of this study was to determine if, in humans, blood cells contribute in production of circulating acyl-CNTs and associate with whole-body fat metabolism. METHODS AND RESULTS: Eight non-diabetic healthy women (age: 47 ± 19 y; BMI: 26 ± 1 kg·m-2) underwent stable isotope tracer infusion and hyperinsulinemic-euglycemic clamp study to determine in vivo whole-body fatty acid flux and insulin sensitivity. Blood samples collected at baseline (0 min) and after 3 h of clamp were used to determine the synthesis rate of palmitoyl-carnitine (palmitoyl-CNT) in vitro. The fractional synthesis rate of palmitoyl-CNT was significantly higher during hyperinsulinemia (0.788 ± 0.084 vs. 0.318 ± 0.012%·hr-1, p = 0.001); however, the absolute synthesis rate (ASR) did not differ between the periods (p = 0.809) due to ∼30% decrease in blood palmitoyl-CNT concentration (p = 0.189) during hyperinsulinemia. The ASR of palmitoyl-CNT significantly correlated with the concentration of acyl-CNTs in basal (r = 0.992, p < 0.001) and insulin (r = 0.919, p = 0.001) periods; and the basal ASR significantly correlated with plasma palmitate oxidation (r = 0.764, p = 0.027). CONCLUSION: In women, blood cells contribute to plasma acyl-CNT levels and the acyl-CNT production is linked to plasma palmitate oxidation, a marker of whole-body fat metabolism. Future studies are needed to confirm the role of blood cells in acyl-CNT and lipid metabolism under different physiological (i.e., in response to meal) and pathological (i.e., hyperlipidemia, IR and T2D) conditions.

In vivo triglyceride synthesis in subcutaneous adipose tissue of humans correlates with plasma HDL parameters.

BACKGROUNDS AND AIMS: Low concentrations of plasma HDL-C are associated with the development of atherosclerotic cardiovascular diseases and type 2 diabetes. Here we aimed to explore the relationship between the in vivo fractional synthesis of triglycerides (fTG) in subcutaneous (s.q.) abdominal adipose tissue (AT), HDL-C concentrations and HDL particle size composition in non-diabetic humans. METHODS: The fTG in s.q. abdominal AT was measured in 16 non-diabetic volunteers (7 women, 9 men; Age: 49 ± 20 years; BMI: 31 ± 5 kg/m; Fasting Plasma Glucose: 90 ± 10 mg/dl) after (2)H2O labeling. HDL-C concentration and subclasses, large (L-HDL), intermediate (I-HDL) and small (S-HDL) were measured. RESULTS: Linear regression analyses demonstrated significant associations of fTG with plasma concentration of HDL-C (r = 0.625,p = 0.009) and percent contribution of L-HDL (r = 0.798,p < 0.001), I-HDL (r = -0.765,p < 0.001) and S-HDL (r = -0.629, p = 0.009). When analyses were performed by gender, the associations remained significant in women (HDL-C: r = 0.822,p = 0.023; L-HDL: r = 0.892,p = 0.007; I-HDL: r = -0.927,p = 0.003) but not men. CONCLUSIONS: Our study demonstrated an in vivo association between subcutaneous abdominal adipose tissue lipid dynamics and HDL parameters in humans, but this was true for women not men. Positive association with L-HDL and negative with I-HDL suggest that subcutaneous abdominal adipose tissue lipid dynamics may play an important role in production of mature functional HDL particles. Further studies evaluating the mechanism responsible for these associations and the observed gender differences are important and warranted to identify potential novel targets of intervention to increase the production of atheroprotective subclasses of HDL-Cs and thus decreasing the risks of development of atherosclerotic conditions.

Peripheral adipose tissue insulin resistance alters lipid composition and function of hippocampal synapses.

Compelling evidence indicates that type 2 diabetes mellitus, insulin resistance (IR), and metabolic syndrome are often accompanied by cognitive impairment. However, the mechanistic link between these metabolic abnormalities and CNS dysfunction requires further investigations. Here, we evaluated whether adipose tissue IR and related metabolic alterations resulted in CNS changes by studying synapse lipid composition and function in the adipocyte-specific ecto-nucleotide pyrophosphate phosphodiesterase over-expressing transgenic (AtENPP1-Tg) mouse, a model characterized by white adipocyte IR, systemic IR, and ectopic fat deposition. When fed a high-fat diet, AtENPP1-Tg mice recapitulate essential features of the human metabolic syndrome, making them an ideal model to characterize peripherally induced CNS deficits. Using a combination of gas chromatography and western blot analysis, we found evidence of altered lipid composition, including decreased phospholipids and increased triglycerides (TG) and free fatty acid in hippocampal synaptosomes isolated from high-fat diet-fed AtENPP1-Tg mice. These changes were associated with impaired basal synaptic transmission at the Schaffer collaterals to hippocampal cornu ammonis 1 (CA1) synapses, decreased phosphorylation of the GluN1 glutamate receptor subunit, down-regulation of insulin receptor expression, and up-regulation of the free fatty acid receptor 1.

Liraglutide reduces oxidative stress and restores heme oxygenase-1 and ghrelin levels in patients with type 2 diabetes: a prospective pilot study.

CONTEXT: Liraglutide is a glucagon-like peptide-1 analog and glucose-lowering agent whose effects on cardiovascular risk markers have not been fully elucidated. OBJECTIVE: We evaluated the effect of liraglutide on markers of oxidative stress, heme oxygenase-1 (HO-1), and plasma ghrelin levels in patients with type-2 diabetes mellitus (T2DM). DESIGN AND SETTING: A prospective pilot study of 2 months' duration has been performed at the Unit of Diabetes and Cardiovascular Prevention at University of Palermo, Italy. Patients and Intervention(s): Twenty subjects with T2DM (10 men and 10 women; mean age: 57 ± 13 y) were treated with liraglutide sc (0.6 mg/d for 2 wk, followed by 1.2 mg/d) in addition to metformin (1500 mg/d orally) for 2 months. Patients with liver disorders or renal failure were excluded. MAIN OUTCOME MEASURE(S): Plasma ghrelin concentrations, oxidative stress markers, and heat-shock proteins, including HO-1 were assessed. RESULTS: The addition of liraglutide resulted in a significant decrease in glycated hemoglobin (HbA1c) (8.5 ± 0.4 vs 7.5 ± 0.4%, P < .0001). In addition, plasma ghrelin and glutathione concentrations increased (8.2 ± 4.1 vs 13.6 ± 7.3 pg/ml, P = .0007 and 0.36 ± 0.06 vs 0.44 ± 0.07 nmol/ml, P = .0002, respectively), whereas serum lipid hydroperoxides and HO-1 decreased (0.11 ± 0.05 vs 0.04 ± 0.07 pg/ml, P = .0487 and 7.7 ± 7.7 vs 3.6 ± 1.8 pg/ml, P = .0445, respectively). These changes were not correlated with changes in fasting glycemia or HbA1c. CONCLUSIONS: In a 2-months prospective pilot study, the addition of liraglutide to metformin resulted in improvement in oxidative stress as well as plasma ghrelin and HO-1 concentrations in patients with T2DM. These findings seemed to be independent of the known effects of liraglutide on glucose metabolism.

Influence of liver triglycerides on suppression of glucose production by insulin in men.

CONTEXT: The ability of insulin to suppress hepatic glucose production is impaired among subjects with increased intrahepatic triglycerides (IHTG). However, little is known about the roles of insulin on the supporting fluxes of glucose production among patients with fatty liver. OBJECTIVE: To evaluate the effects of insulin on fluxes through the three potential sources of plasma glucose (glycerol, the citric acid cycle, and glycogen) among patients with fatty liver. Design, Settings, Participants, and Intervention: Nineteen men with a range of IHTG (∼0.5% to 23%) were studied after an overnight fast and during hyperinsulinemia using magnetic resonance spectroscopy and stable isotope tracers. MAIN OUTCOME MEASURES: IHTG, gluconeogenesis from glycerol, gluconeogenesis from the citric acid cycle, glycogenolysis, and (13)C-labeled glucose produced from the citric acid cycle during hyperinsulinemia were measured. RESULTS: Men with high IHTG had higher fluxes through all pathways contributing to glucose production during hyperinsulinemia, compared to men with low IHTG, but they had similar fluxes after the fast. Consequently, men with fatty liver had impaired insulin efficiency in suppressing total glucose production as well as fluxes through all three biochemical pathways contributing to glucose. The detection of glucose isotopomers with (13)C arising from [U-(13)C3]propionate ingested during hyperinsulinemia demonstrated continuous gluconeogenesis from the citric acid cycle in all subjects. CONCLUSIONS: These findings challenge the concept that individual glucose production pathways are selectively dysregulated during hepatic insulin resistance. Overproduction of glucose during hyperinsulinemia in men with fatty liver results from inadequate suppression of all the supporting fluxes of glucose production in response to insulin.

Changes in fat distribution in children following severe burn injury.

BACKGROUND: Children with severe cutaneous burn injury show persistent metabolic abnormalities, including inflammation and insulin resistance. Such abnormalities could potentially increase their future risk for developing type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). This could be related to changes in body composition and fat distribution. METHODS: We studied body composition, fat distribution, and inflammatory cytokines changes in children with severe burn injury up to 6 months from discharge. Sixty-two boys and 35 girls (burn ≥30% of total body surface area) were included. RESULTS: We found a decrease in total body fat and subcutaneous peripheral fat at 6 months (6% and 2%, respectively; P<0.05 each). An inverse correlation between the decrease in peripheral fat content at 6 months and the extent of burn injury (r=-041, P=0.02) was also observed. In addition, there was a 12% increase in serum tumor necrosis factor-α (TNF-α) (P=0.01 vs. discharge) and 9% decrease in serum interleukin-10 (IL-10) (P<0.0001 vs. discharge) over 6 months after burn. CONCLUSION: Severe burn injury in children is associated with changes in body fat content and distribution up to 6 months from hospital discharge. These changes, accompanied by persisting systemic inflammation, could possibly mediate the observed persistence of insulin resistance, predisposing burn patients to the development of T2DM and CVD.

Hypoglycemic effects and mechanisms of electroacupuncture on insulin resistance.

The aim of this study was to investigate effects and mechanisms of electroacupuncture (EA) on blood glucose and insulin sensitivity in mice fed a high-fat diet. Both wild-type (WT) and adipose ectonucleotide pyrophosphate phosphodiesterase (ENPP1) transgenic (TG) mice were fed a high-fat diet for 12 wk; for each mouse, an intraperitoneal glucose tolerance test (IPGTT) and insulin tolerance test (ITT) were performed with or without EA at abdomen or auricular areas. A high-fat diet-induced insulin resistance in both WT and TG mice. In the WT mice, EA at 3 Hz and 15 Hz, but not at 1 Hz or 100 Hz, via CV4+CV12 significantly reduced postprandial glucose levels; EA at 3 Hz was most potent. The glucose level was reduced by 61.7% at 60 min and 74.5% at 120 min with EA at 3 Hz (all P < 0.001 vs. control). Similar hypoglycemic effect was noted in the TG mice. On the contrary, EA at auricular points increased postprandial glucose level (P < 0.03). 4). EA at 3 Hz via CV4+CV12 significantly enhanced the decrease of blood glucose after insulin injection, suggesting improvement of insulin sensitivity. Plasma free fatty acid was significantly suppressed by 42.5% at 15 min and 50.8% at 30 min with EA (P < 0.01) in both WT and TG mice. EA improves glucose tolerance in both WT and TG mice fed a high-fat diet, and the effect is associated with stimulation parameters and acupoints and is probably attributed to the reduction of free fatty acid.

Liraglutide decreases carotid intima-media thickness in patients with type 2 diabetes: 8-month prospective pilot study.

BACKGROUND: Liraglutide, a long-acting glucagon-like peptide-1 (GLP-1) analog, has several non- glycemic properties, but its effect on carotid intima-media thickness (IMT), a recognized marker of subclinical atherosclerosis, is still unknown. METHODS: A prospective study of 8 months duration in 64 patients with type-2 diabetes and no prior history of coronary artery disease evaluated whether adding liraglutide to metformin affects carotid IMT, measured by color doppler ultrasound. RESULTS: After 8 months, fasting glucose decreased by 2.1 mmol/l and HbA1c by 1.9% (p < 0.01 for all). Liraglutide reduced total-cholesterol and triglycerides by 10%, and LDL-cholesterol by 19%, whereas HDL-cholesterol increased by 18% (p < 0.01 for all lipid changes). Carotid IMT decreased from 1.19 ± 0.47 to 0.94 ± 0.21 mm (p < 0.01). Yet, changes in carotid IMT did not correlate with changes in any other variable studied. CONCLUSIONS: Liraglutide decreases carotid IMT after 8 months treatment independently of its effect on plasma glucose and lipids concentrations. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01715428.

Adipokines and lipoproteins: modulation by antihyperglycemic and hypolipidemic agents.

Adipose tissue is an endocrine organ that secretes a number of hormones and metabolically active substances that impact energy metabolism and insulin sensitivity. These inflammatory markers are collectively referred to as adipocytokines, or adipokines. Adipose tissue's functional capacity and metabolic activity vary among individuals, thus partly explaining the incomplete overlap between obesity and the metabolic syndrome. The functional failure of adipose tissues results in changed energy delivery and impaired glucose consumption, triggering self-regulatory mechanisms to maintain homeostasis. Antihyperglycemic, hypolipidemic, antiobesity, and angiotensin II receptor blocker drugs influence adipokine levels in different ways. However, clinical data are still scarce and the clinical relevance of these effects needs to be fully determined.