Orally administered whey proteins have comparable effect on C-peptide secretion in healthy subjects as standard C-peptide stimulation tests.
Physiol Res. 2012 Dec 13. Epub 2012 Dec 13. PMID: 23234418
Centre for Research of Diabetes, Metabolism and Nutrition, Third Faculty of Medicine, Charles University, Prague, Czech Republic. firstname.lastname@example.org.
Our study compared total C-peptide secretion after administration of whey proteins and whey proteins in combination with glucose with results of classical tests assessing beta cell function in the pancreas of healthy individuals. Eight young, healthy (7 males, 1 female; aged 20-26 years), non-obese (BMI: 17-25.9 kg/m(2)) participants with normal glucose tolerance underwent six C-peptide secretion tests. Three secretion tests measured C-peptide response to orally administered substances: whey proteins only (OWT), whey proteins with glucose (OWGT) and glucose only (OGTT); while three secretion tests measured C-peptide response to intravenously administered substances: arginine (AST), glucagon (GST) and glucose (IVGTT). OWT stimulated a greater (93%, p<0.05) C-peptide response than AST and a 64% smaller response (p<0.05) than OGTT. OWT also showed lower variability (p<0.05) in C-peptide responses compared to OWGT and OGTT. The greatest total C-peptide response was induced by OWGT (36% higher than glucose). OWT consistently increased C-peptide concentrations with lower individual variability, while insignificantly increasing glucose levels. Results of this study suggest that both dietology and beta-cells capacity testing could take advantage of the unique property of whey proteins to induce C-peptide secretion.