Publications by authors named "R DeFronzo"

Context: Increased mesenteric visceral fat is associated with the metabolic syndrome, insulin resistance, and type 2 diabetes.

Methods: Using Targeted Cell Separation and Extraction Technology (TC-SET), we examined the effect of removal of intra-abdominal fat, specifically small bowel mesenteric fat, on glycemic control and insulin sensitivity in 7 obese, poorly controlled type 2 diabetic individuals (HbA1c = 8.9±0.

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Objective: The glycemic-independent actions of glucagon-like peptide-1 (GLP-1) in the prandial state in humans are unknown. We examined the contribution of GLP-1 to β-cell secretory response (primary endpoint) and glucose metabolism during protein ingestion under basal glycemia, as well as whether these responses are affected by rerouted gut after gastric bypass (GB) or sleeve gastrectomy (SG).

Methods: Insulin secretion rate (ISR) and glucose fluxes during a 50-g oral protein load were compared among 10 nondiabetic individuals with GB, 9 with SG, and 7 non-operated controls (CN), with and without intravenous infusion of exendin(9-39) (Ex-9), a GLP-1 receptor (GLP-1R) antagonist.

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Aims: To investigate the effect of sodium-glucose co-transporter 2 inhibitor [SGLT-2i] therapy on renal haemodynamics in T2D patients with glomerular hyperfiltration.

Materials And Methods: Sixty T2D patients with elevated [HYPER] and normal [NORMO] GFR were randomized to dapagliflozin 10 mg/day [DAPA/HYPER, n = 15; DAPA/NORMO, n = 15] or to metformin/glipizide [CONTROL/HYPER, n = 15; CONTROL/NORMO, n = 15] to reach similar glycaemic control after 4 months. GFR was measured with Iohexol and hyperfiltration was empirically defined as >125 mL/min/1.

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We examined the effect of increased levels of plasma ketones on left ventricular (LV) function, myocardial glucose uptake (MGU), and myocardial blood flow (MBF) in patients with type 2 diabetes (T2DM) with heart failure. Three groups of patients with T2DM (n = 12 per group) with an LV ejection fraction (EF) ≤50% received incremental infusions of β-hydroxybutyrate (β-OH-B) for 3-6 h to increase the plasma β-OH-B concentration throughout the physiologic (groups I and II) and pharmacologic (group III) range. Cardiac MRI was performed at baseline and after each β-OH-B infusion to provide measures of cardiac function.

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Introduction: Low carbohydrate ketogenic diets have received renewed interest for the treatment of obesity and type 2 diabetes. These diets promote weight loss, improve glycemic control, and reduce insulin resistance. However, whether the improvements in glycemic control and insulin sensitivity are secondary to the weight loss or result from a direct effect of hyperketonemia is controversial.

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