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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.

Background-Hyperglycemia impairs functional properties of cytosolic and nuclear proteins via O-linked glycosylation modification (O-GlcNAcylation). We studied the effects of O-GlcNAcylation on insulin signaling in human coronary artery endothelial cells. Methods and Results-O-GlcNAcylation impaired the metabolic branch of insulin signaling, ie, insulin receptor (IR) activation of the IR substrate (IRS)/phosphatidylinositol 3-kinase (PI3-K)/Akt, whereas it enhanced the mitogenic branch, ie, ERK-1/2 and p38 (mitogen-activated protein kinase). Both in vivo and in vitro phosphorylation of endothelial nitric oxide synthase (eNOS) by Akt were reduced by hyperglycemia and hexosamine activation. Insulin-induced eNOS activity in vivo was reduced by hyperglycemia and hexosamine activation, which was coupled to increased activation and expression of matrix metalloproteinase-2 and -9; these phenomena were reversed by inhibition of the hexosamine pathway. Finally, carotid plaques from type 2 diabetic patients showed increased endothelial O-GlcNAcylation with respect to nondiabetics. Conclusions-Our

Insulin receptor substrate (IRS) molecules are key mediators in insulin signaling and play a central role in maintaining basic cellular functions such as growth, survival, and metabolism. They act as docking proteins between the insulin receptor and a complex network of intracellular signaling molecules containing Src homology 2 (SH2) domains. Four members (IRS-1, IRS-2, IRS-3, IRS-4) of this family have been identified that differ as to tissue distribution, subcellular localization, developmental expression, binding to the insulin receptor, and interaction with SH2 domain-containing proteins. Results from targeted disruption of the IRS genes in mice have provided important clues to the functional differences among these related molecules, suggesting they play different and specific roles in vivo. The available data are consistent with the notion that IRS-1 and IRS-2 are not functionally interchangeable in tissues that are responsible for glucose production (liver), glucose uptake (skeletal muscle and adipose tissue), and insulin production (pancreatic beta cells). In fact, IRS-1 appears to have its major role in skeletal muscle whereas IRS-2 appears to regulate hepatic insulin action as well as pancreatic beta cell development and survival. By contrast, IRS-3 and IRS-4 genes appear to play a redundant role in the IRS signaling system. Defects in muscle IRS-1 expression and function have been reported in insulin-resistant states such as obesity and type 2 diabetes. Several polymorphisms in the IRS genes have been identified, but only the Gly-->Arg972 substitution of IRS-1, interacting with environmental factors, seems to have a pathogenic role in the development of type 2 diabetes. In contrast, polymorphisms of the other IRS genes do not appear to contribute to type 2 diabetes.

OBJECTIVETo investigate the dose-response relationship of semaglutide versus placebo and open-label liraglutide in terms of glycemic control in patients with type 2 diabetes. RESEARCH DESIGN AND METHODSThis was a 12-week, randomized, double-blind phase 2 trial. Patients (n = 415) were randomized to receive a subcutaneous injection of semaglutide once weekly without dose escalation (0.1-0.8 mg) or with dose escalation (E) (0.4 mg steps to 0.8 or 1.6 mg E over 1-2 weeks), open-label liraglutide once daily (1.2 or 1.8 mg), or placebo. The primary end point was change in HbA 1c level from baseline. Secondary end points included change in body weight, safety, and tolerability. RESULTSSemaglutide dose-dependently reduced the level of HbA 1c from baseline (8.1 6 0.8%) to week 12 by up to 21.7%, and body weight by up to 24.8 kg (1.6 mg E, P < 0.001 vs. placebo). Up to 81% of patients achieved an HbA 1c level of <7%. HbA 1c level and weight reductions with semaglutide 1.6 mg E were greater than those with liraglutide 1.2 and 1.8 mg (based on unadjusted CIs), but adverse events (AEs) and withdrawals occurred more frequently. The incidence of nausea, vomiting, and withdrawal due to gastrointestinal AEs increased with the semaglutide dose; most events were mild to moderate, transient, and ameliorated by dose escalation. There were no major episodes of hypoglycemia and few cases of injection site reactions. CONCLUSIONSAfter 12 weeks, semaglutide dose-dependently reduced HbA 1c level and weight in patients with type 2 diabetes. No unexpected safety or tolerability concerns were identified; gastrointestinal AEs typical of glucagon-like peptide 1 receptor agonists were mitigated by dose escalation. On this basis, weekly semaglutide doses of 0.5 and 1.0 mg with a 4-week dose escalation were selected for phase 3.