Background: Glucagon-like peptide 1 agonists differ in chemical structure, duration of action and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. Methods: We randomly assigned patients with type 2 diabetes and cardiovascular disease to the addition of once-weekly subcutaneous injection of albiglutide (30 mg to 50 mg) or matching placebo to standard care. We hypothesized that albiglutide would be noninferior to placebo for the primary outcome of first occurrence of cardiovascular death, myocardial infarction, or stroke. If noninferiority was confirmed by an upper limit of the 95% confidence interval for the hazard ratio of less than 1.30, closed-testing for superiority was prespecified. Findings: Overall, 9463 participants were followed for a median of 1.6 years. The primary composite outcome occurred in 338 of 4731 patients (7.1%; 4.6 events per 100 person-years) in the albiglutide group and in 428 of 4732 patients (9.0%; 5.9 events per 100 person-years) in the placebo group (hazard ratio, 0.78; 95% confidence interval [CI ], 0.68 to 0.90), indicating that albiglutide, was superior to placebo (P<0.0001 for noninferiority, P=0.0006 for superiority). The incidence of acute pancreatitis (albiglutide 10 patients and placebo 7 patients), pancreatic cancer (6 and 5), medullary thyroid carcinoma (0 and 0), and other serious adverse events did not differ significantly between the two groups. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. (Funded by GlaxoSmithKline; Harmony Outcomes ClinicalTrials.gov number, NCT02465515.) noninferiority; P = 0.06 for superiority). There seems to be variation in the results of existing trials with GLP-1 receptor agonists, which if correct, might reflect drug structure or duration of action, patients studied, duration of follow-up or other factors.

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To determine whether the impaired insulin-stimulated glucose uptake in obese individuals is associated with altered insulin receptor signaling, we measured both glucose uptake and early steps in the insulin action pathway in intact strips of human skeletal muscle. Biopsies of rectus abdominus muscle were taken from eight obese and eight control subjects undergoing elective surgery (body mass index 52.9±3.6 vs 25.7±0.9). Insulin-stimulated 2-deoxyglucose uptake was 53% lower in muscle strips from obese subjects. Additional muscle strips were incubated in the basal state or with i0-7 M insulin for 2, 15, or 30 min. In the lean subjects, tyrosine phosphorylation of the insulin receptor and insulin receptor substrate-i (IRS-1), measured by immunoblotting with anti-phosphotyrosine antibodies, was significantly increased by insulin at all time points. In the skeletal muscle from the obese subjects, insulin was less effective in stimulating tyrosine phosphorylation (maximum receptor and IRS-1 phosphorylation decreased by 35 and 38%, respectively). Insulin stimulation of IRS-1 immunoprecipitable phosphatidylinositol 3-kinase (PI 3-kinase) activity also was markedly lower in obese subjects compared with controls (10-vs 35-fold above basal, respectively). In addition, the obese subjects had a lower abundance of the insulin receptor, IRS-1, and the p85 subunit of PI 3-kinase (55, 54, and 64% of nonobese, respectively). We conclude that impaired insulinstimulated glucose uptake in skeletal muscle from severely obese subjects is accompanied by a deficiency in insulin receptor signaling, which may contribute to decreased insulin action. (J. Clin. Invest. 1995.95:2195-2204 Key words:

OBJECTIVEThis study compared the efficacy and safety of once-weekly dulaglutide, a glucagonlike peptide-1 receptor agonist, with daily insulin glargine, both combined with maximally tolerated doses of metformin and glimepiride in patients with type 2 diabetes. The primary objective was noninferiority of dulaglutide 1.5 mg to glargine in the HbA 1c change from baseline at 52 weeks. RESEARCH DESIGN AND METHODSIn this 78-week, open-label study, 810 patients were randomized to dulaglutide 1.5 mg, dulaglutide 0.75 mg, or glargine. RESULTSThe baseline mean 6 SD HbA 1c was 8.1 6 1.0% (65.5 6 10.8 mmol/mol). The least squares mean 6 SE HbA 1c change from baseline to the primary end point was 21.08 6 0.06% (211.8 6 0.7 mmol/mol) for dulaglutide 1.5 mg, 20.76 6 0.06% (28.3 6 0.7 mmol/mol) for dulaglutide 0.75 mg, and 20.63 6 0.06% (26.9 6 0.7 mmol/mol) for glargine, with an end point mean 6 SD dose of 29 6 26 units (0.33 6 0.24 units/kg), and a fasting plasma glucose (mean 6 SD) of 118 6 23 mg/dL from self-monitored plasma glucose. Statistical criteria for superiority were met with dulaglutide 1.5 mg and for noninferiority with dulaglutide 0.75 mg. More patients on dulaglutide 1.5 mg achieved HbA 1c targets <7.0% (53 mmol/mol) versus glargine (P < 0.001). Body weight decreased with dulaglutide and increased with glargine. Total hypoglycemia rates were lower with dulaglutide; severe hypoglycemia was minimal. Increases in pancreatic enzymes were observed for dulaglutide. Incidence of nausea (15.4, 7.7, and 1.5%) and diarrhea (10.6, 9.2, and 5.7%) were more common with dulaglutide 1.5 mg and 0.75 mg than with glargine. CONCLUSIONSOnce-weekly dulaglutide 1.5 mg, compared with daily insulin glargine without forced titration, demonstrated greater HbA 1c reduction and weight loss, with a higher incidence of gastrointestinal adverse events and a lower risk of hypoglycemia.

The insulin-like growth factor (IGF)-I is implicated in the regulation of protein turnover and exerts potent mitogenic and differentiating effects on most cell types. IGF-I biological actions are mediated by the IGF-I receptor, comprised of two extra-cellular alpha-subunits, containing hormone binding sites, and two membrane-spanning beta-subunits, encoding an intracellular tyrosine kinase. Hormone binding activates the receptor kinase, leading to receptor autophosphorylation and tyrosine phosphorylation of multiple substrates, including the IRS and Shc proteins. Through these initial tyrosine phosphorylation reactions, IGF-I signals are transduced to a complex network of intracellular lipid and serine/threonine kinases that are ultimately responsible for cell proliferation, modulation of tissue differentiation, and protection from apoptosis. This review will focus on the IGF-I receptor structure and function, its intracellular signaling pathways, and some important implications of the activation of the IGF-I signal transduction system in specific tissues.

Background Weight loss is a milestone in the prevention of chronic diseases associated with high morbility and mortality in industrialized countries. Very-low calorie ketogenic diets (VLCKDs) are increasingly used in clinical practice for weight loss and management of obesity-related comorbidities. Despite evidence on the clinical benefits of VLCKDs is rapidly emerging, some concern still exists about their potential risks and their use in the long-term, due to paucity of clinical studies. Notably, there is an important lack of guidelines on this topic, and the use and implementation of VLCKDs occurs vastly in the absence of clear evidence-based indications. Purpose We describe here the biochemistry, benefits and risks of VLCKDs, and provide recommendations on the correct use of this therapeutic approach for weight loss and management of metabolic diseases at different stages of life.

Adipose tissue is now recognized to have a multitude of functions that are of importance in the regulation of energy balance and substrate metabolism. Different hormones, in particular insulin and catecholamines, govern the storage and utilization of energy in the triglyceride depots. In addition, adipocytes produce several different substances with endocrine or paracrine functions, which regulate the overall energetic homeostasis. With excess energy storage, obesity develops, leading to increased risk for type 2 diabetes and cardiovascular disease. The distribution of body fat appears to be even more important than the total amount of fat. Abdominal and, in particular, visceral adiposity is strongly linked to insulin resistance, type 2 diabetes, hypertension and dyslipidaemia, leading to increased risk of cardiovascular disease. The adverse metabolic impact of visceral fat has been attributed to distinct biological properties of adipocytes in this depot compared with other adipose tissue depots. Indeed, regional variations in the metabolic activity of fat cells have been observed. Furthermore, expression studies aiming at defining the unique biological properties of adipose tissues from distinct anatomical sites have identified depot-related differences in the protein content of fat-produced molecules. In this review we wish to summarize important results from the literature and also some recent data from our own work. The main scope is to describe the biological functions of adipose tissue, and to focus on metabolic, hormonal, and signalling differences between fat depots.

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