Stefania Camastra

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BACKGROUND Insulin resistance is a risk factor for type 2 diabetes and cardiovascular disease progression. Current diagnostic tests, such as glycemic indicators, have limitations in the early detection of insulin resistant individuals. We searched for novel biomarkers identifying these at-risk subjects. METHODS Using mass spectrometry, non-targeted(More)
OBJECTIVE To quantitate the separate impact of obesity and hyperglycemia on the incretin effect (i.e., the gain in beta-cell function after oral glucose versus intravenous glucose). RESEARCH DESIGN AND METHODS Isoglycemic oral (75 g) and intravenous glucose administration was performed in 51 subjects (24 with normal glucose tolerance [NGT], 17 with(More)
BACKGROUND Because hyperinsulinemia acutely stimulates adrenergic activity, it has been postulated that chronic hyperinsulinemia may lead to enhanced sympathetic tone and cardiovascular risk. METHODS AND RESULTS In 21 obese (body mass index, 35+/-1 kg/m(2)) and 17 lean subjects, we measured resting cardiac output (by 2-dimensional echocardiography),(More)
Obesity is a frequent cause of insulin resistance and poses a major risk for diabetes. Abnormal fat deposition within skeletal muscle has been identified as a mechanism of obesity-associated insulin resistance. We tested the hypothesis that dietary lipid deprivation may selectively deplete intramyocellular lipids, thereby reversing insulin resistance.(More)
The contribution of gluconeogenesis (GNG) to endogenous glucose output (EGO) in type 2 diabetes is controversial. Little information is available on the separate influence of obesity on GNG. We measured percent GNG (by the 2H2O technique) and EGO (by 6,6-[2H]glucose) in 37 type 2 diabetic subjects (9 lean and 28 obese, mean fasting plasma glucose [FPG] 8.3(More)
Metabolomic screening of fasting plasma from nondiabetic subjects identified α-hydroxybutyrate (α-HB) and linoleoyl-glycerophosphocholine (L-GPC) as joint markers of insulin resistance (IR) and glucose intolerance. To test the predictivity of α-HB and L-GPC for incident dysglycemia, α-HB and L-GPC measurements were obtained in two observational cohorts,(More)
CONTEXT In obese patients with type 2 diabetes (T2DM), Roux-en-Y-gastric-bypass (RYGB) and sleeve gastrectomy (SLG) improve glycemic control. OBJECTIVE The objective of this study was to investigate the mechanisms of surgery-induced T2DM improvement and role of gastrointestinal hormones. PATIENTS, SETTING, AND INTERVENTION: In 35 patients with T2DM, we(More)
To study the acute effects of insulin on autonomic control of cardiac function, we performed spectral analysis of heart rate variability and measured cardiac dynamics (by two-dimensional echocardiography) in 18 obese (BMI = 35 +/- 1 kg.m-2) and 14 lean (BMI = 24 +/- 1 kg.m-2) subjects in the basal state and in response to physiological hyperinsulinemia (1(More)
CONTEXT Bariatric surgery can induce remission in a high proportion of severely obese patients with type 2 diabetes mellitus (T2DM). OBJECTIVE Our objective was to investigate predictors and mechanisms of surgery-induced diabetes remission. PATIENTS AND SETTING Forty-three morbidly obese subjects (body mass index = 45.6 ± 5.0 kg/m(2)), 32 with T2DM and(More)
Bariatric surgery consistently induces remission of type 2 diabetes. We tested whether there are diabetes-specific mechanisms in addition to weight loss. We studied 25 morbidly obese patients (BMI 51.7 ± 1.5 kg/m2 [mean ± SEM]), 13 with non-insulin-treated type 2 diabetes (HbA1c 7.1 ± 0.5% [54 ± 5 mmol/mol]), before and at 2 weeks and 1 year after Roux-en-Y(More)