Effects of wine intake on postprandial plasma amino acid and protein kinetics in type 1 diabetes.

Background: Alcohol may impair protein turnover and insulin sensitivity in vivo.

Objective: The acute effects of moderate wine intake on amino acid kinetics and on the fractional synthetic rate (FSR) of albumin and fibrinogen in patients with type 1 diabetes were studied.

Design: Six patients with type 1 diabetes ingested an elementary mixed meal (46 kJ/kg) over 4 h, first without and 3 mo later with approximately 300 mL red wine. Postprandial glucose concentrations were maintained at <10 mmol/L.

Results: Postprandially, the FSR of fibrinogen was approximately 30% greater (21.5 +/- 6.6% compared with 14.1 +/- 3.6% of pool/d; P < 0.01) and glucagon concentrations were approximately 40% greater (103 +/- 20 compared with 61 +/- 13 ng/L; P < 0.015) with wine than without wine. However, the FSR of albumin and the rates of appearance of total and endogenous phenylalanine and leucine were not significantly different between treatments. First-pass splanchnic uptake (in micromol*kg(-1)*min(-1)) of dietary phenylalanine (0.22 +/- 0.02 compared with 0.19 +/- 0.02) and leucine (0.25 +/- 0.04 compared with 0.14 +/- 0.02) were greater with wine (P < 0.05), whereas dietary phenylalanine oxidation was lower with wine, by approximately 25% (0.10 +/- 0.02 compared with 0.14 +/- 0.01 micromol.kg(-1).min(-1); P < 0.05). Selected amino acid concentrations were significantly lower but glutamate concentrations were significantly higher with wine.

Conclusions: In insulin-infused patients with type 1 diabetes, moderate wine intake with a meal resulted in 1) a higher fibrinogen FSR, glucagon concentration, and first-pass splanchnic uptake of leucine and phenylalanine; 2) lower dietary phenylalanine oxidation; 3) selective changes in plasma amino acid concentrations; 4) and no impairment in endogenous proteolysis and albumin synthesis.