Diabetes Mellitus, Type 2
Conditions
Brief summary
The purpose of this study is: * to measure the size of the effect on glucose tolerance of a small mixed protein and lipid meal given as a pre-load in individuals with different glucose tolerance status * to investigate the underlying mechanisms by accurately evaluating beta cell function, insulin sensitivity, insulin clearance and glucose kinetics (oral absorption, endogenous production, rate of utilization) together with gut hormones plasma concentration.
Detailed description
As supported by experimental and clinical data, oral carbohydrate tolerance is influenced by the coingestion of nutrients through multiple mechanisms. The ingestion itself, the contact with the gastric mucosa, the arrival into the intestine and the subsequent digestion are known to produce neural reflexes, hormonal responses and plasma substrates gradients which, by modulating gastric emptying, insulin secretion and insulin clearance participate in the regulation of postprandial glycaemia. The size of this effect is influenced by a number of factors: the specific nutrient chemical characteristics (fat vs protein and composition) and their physical properties (solid vs liquid), the timing (pre-load vs coingestion) and finally the individual glucose tolerance status. To our knowledge, the effect on glucose excursions of a combination of protein and fat given before carbohydrate is still unknown and also unknown is the contribution of different mechanisms involved in the control of glucose homeostasis in subjects with different degrees of glucose tolerance.
Interventions
DIETARY_SUPPLEMENTSmall mixed protein and lipid meal
Ingestion of a small mixed protein and lipid meal 30 minutes before glucose
Sponsors
Azienda Ospedaliero, Universitaria Pisana
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy, prediabetic or diet-controlled type 2 diabetic patients * Subjects ≥ 18 and ≤65 years of age * Lean, Overweight or Obese (BMI: 18 to 35 kg/m2) * Normal liver and kidney function * Normal thyroid function * Read and understood the informed consent form and signed it voluntarily
Exclusion criteria
* Liver, heart, kidney, lung, infectious, neurological, psychiatric, immunological or neoplastic diseases. * Type 1 or insulin treated diabetes. * Pregnancy or lactation * Illicit drug abuse or alcoholism * Subject treated with insulin or treatment * Subjects taking anoretic drugs * Subjects on steroid treatment * Subjects after bariatric surgery.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Plasma glucose response during the Oral Glucose Tolerance Test | 120 minutes |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Insulin sensitivity, estimated from glucose and insulin levels during the Oral Glucose Tolerance Test with the use of Oral Glucose Insulin Sensitivity index | 120 minutes | The Oral Glucose Insulin Sensitivity index (OGIS; equation for a 2-h oral glucose test with a glucose dose of 75 g) is the mean glucose clearance change (basal vs OGTT 60-120 min), divided by the mean plasma insulin concentration gradient over the same time interval. |
| Insulin clearance, estimated by calculating the Insulin secretion/Plasma insulin ratio | 120 minutes | — |
| Glucose fluxes (intestinal glucose absorption, endogenous glucose production, rate of disappearance of plasma glucose), assessed by modeling glucose tracers enrichments using a standard double tracers technique | 120 minutes | — |
| Incretin secretion (plasma GLP-1, plasma GIP) | 120 minutes | — |
| Insulin secretion, estimated from C-peptide deconvolution | 120 minutes | — |
| Plasma Non Esterified Fatty Acids | 120 minutes | — |
| Beta cells function parameters (glucose sensitivity, rate sensitivity, potentiation factor ratio), calculated by modeling insulin secretion and glucose concentration. | 120 minutes | — |
| Endothelial function assessed as the reactive hyperemia index by an EndoPAT device | fasting, 60 min and 120 min during the control and preload OGTT | — |
| Plasma glucagon | 120 minutes | — |
Countries
Italy
Outcome results
None listed