Protein preload enhances vildagliptin efficacy in type 2 diabetes
Men with well-controlled type 2 diabetes treated with metformin saw reduced postprandial glucose levels when combining the DPP-IV inhibitor vildagliptin with a whey protein preload as add-on therapy, according to research in Diabetes Care.
Tongzhi Wu, MBBS, PhD, of the University of Adelaide in Australia, and colleagues analyzed data from 22 men with type 2 diabetes treated with metformin (mean age, 64 years; mean BMI, 27.9 kg/m²; mean HbA1c, 6.6%; mean duration of diabetes, 5.6 years; all nonsmokers). On four occasions, each separated by 7 days, researchers assigned the following combinations in random order: either 50 mg vildagliptin or placebo on both the evening before and the morning of each study day (participants consumed a standardized beef lasagna meal with the evening dose). The morning dose was followed, after 60 minutes, by a 250-mL preload drink containing either 25 g whey protein isolate or 25 g control flavoring. Participants consumed a mashed potato meal 30 minutes after consumption of the drink.
Researchers measured plasma glucose, hormone levels and gastric emptying.
Researchers found that participants assigned vildagliptin with the protein drink had higher plasma intact glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide (GIP), slower gastric emptying and lower postprandial glycemia when compared with both the placebo/protein and the vildagliptin/control drink groups (P < .05 for each).
Compared with the placebo/control drink group, the placebo/protein drink group had reduced postprandial peak glycemia; increased plasma insulin, glucagon and incretin hormones (total and intact); and slowed gastric emptying. Participants assigned the vildagliptin/control drink saw reduced peak and area under the curve for glucose, increased plasma intact incretins and slowed gastric emptying, but suppressed plasma glucagon and total incretins (P < .05 each).
“Remarkably, the addition of the whey preload to treatment with vildagliptin approximately doubled the reduction in peak postprandial blood glucose,” the researchers wrote. “The dose of whey, although lower than used previously, proved sufficient to stimulate GLP-1 and GIP secretion and slow gastric emptying.” – by Regina Schaffer
Disclosure: Novartis funded this study and arranged the supply of vildagliptin and placebo. Wu reports receiving research funding from AstraZeneca. Please see the full study for the other authors’ relevant financial disclosures.