RT Journal Article
SR Electronic
T1 Dietary Proteins Contribute Little to Glucose Production, Even Under Optimal Gluconeogenic Conditions in Healthy Humans
JF Diabetes
JO Diabetes
FD American Diabetes Association
SP 1435
OP 1442
DO 10.2337/db12-1208
VO 62
IS 5
A1 Fromentin, Claire
A1 Tomé, Daniel
A1 Nau, Françoise
A1 Flet, Laurent
A1 Luengo, Catherine
A1 Azzout-Marniche, Dalila
A1 Sanders, Pascal
A1 Fromentin, Gilles
A1 Gaudichon, Claire
YR 2013
UL http://diabetes.diabetesjournals.org/content/62/5/1435.abstract
AB Dietary proteins are believed to participate significantly in maintaining blood glucose levels, but their contribution to endogenous glucose production (EGP) remains unclear. We investigated this question using multiple stable isotopes. After overnight fasting, eight healthy volunteers received an intravenous infusion of [6,6-2H2]-glucose. Two hours later, they ingested four eggs containing 23 g of intrinsically, uniformly, and doubly [15N]-[13C]–labeled proteins. Gas exchanges, expired CO2, blood, and urine were collected over the 8 h following egg ingestion. The cumulative amount of dietary amino acids (AAs) deaminated over this 8-h period was 18.1 ± 3.5%, 17.5% of them being oxidized. The EGP remained stable for 6 h but fell thereafter, concomitantly with blood glucose levels. During the 8 h after egg ingestion, 50.4 ± 7.7 g of glucose was produced, but only 3.9 ± 0.7 g originated from dietary AA. Our results show that the total postprandial contribution of dietary AA to EGP was small in humans habituated to a diet medium-rich in proteins, even after an overnight fast and in the absence of carbohydrates from the meal. These findings question the respective roles of dietary proteins and endogenous sources in generating significant amounts of glucose in order to maintain blood glucose levels in healthy subjects.