Gluconeogenesis and protein-induced satiety

• Published in: British journal of nutrition Vol. 107; no. 4; pp. 595 - 600
• Main Authors: Veldhorst, Margriet A. B., Westerterp, Klaas R., Westerterp-Plantenga, Margriet S.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 28-02-2012
• Subjects: 3-Hydroxybutyric Acid - blood; Adult; Appetite Depressants - administration & dosage; Appetite Regulation; Behaviour, Appetite and Obesity; Biological and medical sciences; Blood Glucose - analysis; Body Mass Index; Cross-Over Studies; Diet; Dietary Proteins - administration & dosage; Energy Metabolism; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Gluconeogenesis; Glucose; Glycogen - metabolism; Homeostasis; Humans; Hunger; Ingestion; Male; Nutrition research; Proteins; Satiety Response; Single-Blind Method; Surveys and Questionnaires; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Young Adult; Appetite; Satiety; Glucose homoeostasis; β-Hydroxybutyrate; High-protein diet; Gluconeogenesis; Glucose; Protein; Feeding; Vertebrata; Mammalia; Diet; Gluconeogenesis: Appetite
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114511003254

Increased gluconeogenesis (GNG) has been suggested to contribute to protein-induced satiety via modulation of glucose homoeostasis. The objective was to determine GNG and appetite in healthy human subjects after a high-protein v. a normal-protein diet and to assess whether GNG contributes to protein-induced satiety. A total of twenty-two healthy subjects (ten men and twelve women: age 23 (sem 1) years, BMI 22·1 (sem 0·5) kg/m2) received an isoenergetic high-protein (30/0/70 % of energy from protein/carbohydrate/fat) or normal-protein diet (12/55/33 % of energy from protein/carbohydrate/fat) for 1·5 d in a randomised cross-over design. Appetite ratings were measured using visual analogue scales (VAS); endogenous glucose production and GNG were measured via infusion of [6,6-2H2]glucose and ingestion of 2H2O. Moreover, fasting glucose and β-hydroxybutyrate concentrations were measured. Glycogen stores were lowered at the start with a glycogen-lowering exercise test. During the high-protein compared with the normal-protein diet, GNG was increased and appetite was suppressed (GNG: 148 (sem 7) v. 133 (sem 6) g/24 h, P < 0·05; and 24 h area under the curve for hunger: 694 (sem 46) v. 1055 (sem 52) mm VAS × 24 h, P < 0·001; fullness: 806 (sem 59) v. 668 (sem 64) mm VAS × 24 h, P < 0·05; desire to eat: 762 (sem 48) v. 1004 (sem 66) mm VAS × 24 h, P < 0·001). There was no correlation between appetite ratings and GNG. Glucose concentration was lower (4·09 (sem 0·10) v. 4·89 (sem 0·06) mmol/l, P < 0·001) and β-hydroxybutyrate concentration was higher (1349 (sem 139) v. 234 (sem 25) μmol/l, P < 0·001) after the high-protein compared with the normal-protein diet. In conclusion, after a high-protein diet, GNG was increased and appetite was lower compared with a normal-protein diet; however, these were unrelated to each other. An increased concentration of β-hydroxybutyrate may have contributed to appetite suppression on the high-protein diet.