A lesser postprandial suppression of plasma ghrelin in Prader-Willi syndrome is associated with low fasting and a blunted postprandial PYY response.

OBJECTIVE: Ghrelin and polipeptide YY (PYY) are involved in the regulation of food intake. We evaluated these two peptides and their possible relationship in adult patients with Prader-Willi syndrome (PWS). PATIENTS: Seven patients with PWS, 16 age-sex-BMI matched obese and 42 age-sex matched lean subjects. DESIGN AND MEASUREMENTS: Fasting plasma PYY and ghrelin levels were measured in all subjects and, postprandially until 6 h, in seven matched subjects of each group. RESULTS: Fasting ghrelin levels were higher in PWS than in the other two groups. Fasting PYY levels were lower in patients with PWS than in lean subjects but similar to those in obese subjects. The postprandial decrease in ghrelin concentrations was lower in PWS as compared to the other two groups and therefore the 6-h-postprandial area under the curve (AUC) for ghrelin was higher in PWS than in obese subjects. PYY response after the meal was blunted in patients with PWS, but not in the other two groups that showed a peak at 60 min The AUC for PYY was lower in PWS as compared to the other two groups. Fasting PYY levels correlated negatively with fasting ghrelin levels and with ghrelin AUC and they were the only predictor for ghrelin AUC (beta = -0.464, P = 0.034). The increase in PYY correlated negatively with the decrease in ghrelin at times 60 min and 120 min in PWS. CONCLUSIONS: In PWS, the low decrease in postprandial ghrelin levels could be related to the low fasting PYY concentrations and their blunted postprandial response.

Glycemic and lipid control in hospitalized type 2 diabetic patients: evaluation of 2 enteral nutrition formulas (low carbohydrate-high monounsaturated fat vs high carbohydrate).

BACKGROUND: Type 2 diabetic patients may need enteral nutrition support as part of their treatment. The objective was to compare glycemic and lipid control in hospitalized patients with type 2 diabetes requiring feeding via nasogastric tube using enteral feedings with either a highcarbohydrate or a high-monounsaturated-fat content. METHODS: This trial included type 2 diabetes patients admitted to the hospital for neurologic disorders or head and neck cancer surgery who received either a low-carbohydrate-high-mono-unsaturated-fat (Glucerna) or a high-carbohydrate diet (Precitene Diabet). Glycemic and lipid control was determined weekly. Safety and gastrointestinal tolerance were also assessed. RESULTS: A total of 104 patients were randomized and 63 were evaluable according to preestablished protocol criteria. Median duration of therapy was 13 days in both groups. Mean glucose was significantly increased at 7 days of treatment (p = .006) in the Precitene arm, with no significant variations in the Glucerna arm. Mean weekly blood triglycerides levels in the Precitene arm were increased without reaching statistical significance, whereas patients in the Glucerna arm showed a stable trend. Patients in the Precitene arm showed a significantly higher incidence of diarrhea than patients in Glucerna arm (p = .008), whereas the incidence of nausea was smaller in the Precitene arm than in the Glucerna arm (p = .03). CONCLUSIONS: An enteral formula with lower carbohydrate and higher monounsaturated fat (Glucerna) has a neutral effect on glycemic control and lipid metabolism in type 2 diabetic patients compared with a high-carbohydrate and a lower-fat formula (Precitene Diabet).