1. Plasma GLP-1 Response to Oral and Intraduodenal Nutrients in Health and Type 2 Diabetes-Impact on Gastric Emptying
- Author
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Linda E. Watson, Richard L. Young, Christopher K. Rayner, Cong Xie, Karen L. Jones, Weikun Huang, Michael Horowitz, Stijn Soenen, and Tongzhi Wu
- Subjects
Blood Glucose ,endocrine system ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Context (language use) ,Type 2 diabetes ,Biochemistry ,Endocrinology ,Nutrient ,Glucagon-Like Peptide 1 ,Internal medicine ,Medicine ,Humans ,Insulin ,Breath test ,Meal ,medicine.diagnostic_test ,Gastric emptying ,business.industry ,digestive, oral, and skin physiology ,Biochemistry (medical) ,Nutrients ,medicine.disease ,Postprandial Period ,Small intestine ,Postprandial ,medicine.anatomical_structure ,Glucose ,Diabetes Mellitus, Type 2 ,Gastric Emptying ,business - Abstract
Context Both gastric emptying and the secretion of glucagon-like peptide-1 (GLP-1) are major determinants of postprandial glycemia in health and type 2 diabetes (T2D). GLP-1 secretion after a meal is dependent on the entry of nutrients into the small intestine, which, in turn, slows gastric emptying. Objective To define the relationship between gastric emptying and the GLP-1 response to both oral and small intestinal nutrients in subjects with and without T2D. Methods We evaluated: (i) the relationship between gastric emptying (breath test) and postprandial GLP-1 levels after a mashed potato meal in 73 individuals with T2D; (ii) inter-individual variations in GLP-1 response to (a) intraduodenal glucose (4 kcal/min) during euglycemia and hyperglycemia in 11 healthy and 12 T2D, subjects, (b) intraduodenal fat (2 kcal/min) in 15 T2D subjects, and (c) intraduodenal protein (3 kcal/min) in 10 healthy subjects; and (iii) the relationship between gastric emptying (breath test) of 75 g oral glucose and the GLP-1 response to intraduodenal glucose (4 kcal/min) in 21 subjects (9 healthy, 12 T2D). Results The GLP-1 response to the mashed potato meal was unrelated to the gastric half-emptying time (T50). The GLP-1 responses to intraduodenal glucose, fat, and protein varied substantially between individuals, but intra-individual variation to glucose was modest. The T50 of oral glucose was related directly to the GLP-1 response to intraduodenal glucose (r = 0.65, P = 0.002). Conclusion In a given individual, gastric emptying is not a determinant of the postprandial GLP-1 response. However, the intrinsic gastric emptying rate is determined in part by the responsiveness of GLP-1 to intestinal nutrients.
- Published
- 2021