title: The effect of 8 days of strict bed rest on the incretin effect in healthy volunteers.
abstract: Bed rest and physical inactivity are the consequences of hospital admission for many patients. Physical inactivity induces changes in glucose metabolism, but its effect on the incretin effect, which is reduced in, e.g., Type 2 diabetes, is unknown. To investigate how 8 days of strict bed rest affects the incretin effect, 10 healthy nonobese male volunteers underwent 8 days of strict bed rest. Before and after the intervention, all volunteers underwent an oral glucose tolerance test (OGTT) followed by an intravenous glucose infusion (IVGI) on the following day to mimic the blood glucose profile from the OGTT. Blood glucose, serum insulin, serum C-peptide, plasma incretin hormones [glucagon-like peptide (GLP-1) and glucose-dependent insulinotropic peptide (GIP)], and serum glucagon were measured serially during both the OGTT and the IVGI. The incretin effect is calculated as the relative difference between the area under the curve for the insulin response during the OGTT and that of the corresponding IVGI, respectively. Concentrations of glucose, insulin, C-peptide, and GIP measured during the OGTT were higher after the bed rest intervention (all P < 0.05), whereas there was no difference in the levels of GLP-1 and Glucagon. Bed rest led to a mean loss of 2.4 kg of fat-free mass, and induced insulin resistance evaluated by the Matsuda index, but did not affect the incretin effect (P = 0.6). In conclusion, 8 days of bed rest induces insulin resistance, but we did not see evidence of an associated change in the incretin effect.
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; signenielsen@dadlnet.dk.
authors.forename: Signe Tellerup
authors.initials: ST
authors.lastname: Nielsen
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark;
authors.forename: Nina Majlund
authors.initials: NM
authors.lastname: Harder-Lauridsen
authors.affiliation: Rheumatology Division, School of Medicine, University of São Paulo, São Paulo, Brazil;
authors.forename: Fabiana Braga
authors.initials: FB
authors.lastname: Benatti
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark;
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Wedell-Neergaard
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark;
authors.forename: Mark Preben
authors.initials: MP
authors.lastname: Lyngbæk
authors.affiliation: Department of Neuroanaesthesiology, Neuroscience Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Kirsten
authors.identifier: http://orcid.org/0000-0003-3058-1072
authors.initials: K
authors.lastname: Møller
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark;
authors.forename: Bente Klarlund
authors.initials: BK
authors.lastname: Pedersen
authors.affiliation: Centre of Inflammation and Metabolism and the Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark;
authors.forename: Rikke
authors.initials: R
authors.lastname: Krogh-Madsen
mesh_terms: D000293:Adolescent; D000328:Adult; D001510:Bed Rest; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000378:metabolism; D005749:Gastric Inhibitory Polypeptide / Q000097:blood; D005934:Glucagon / Q000097:blood; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test / Q000379:methods; D064368:Healthy Volunteers; D006801:Humans; D054795:Incretins / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D054795:Incretins; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide; D005934:Glucagon; D005947:Glucose
keywords: bed rest; incretins; insulin