{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T08:51:53Z","timestamp":1791276713156,"version":"4.1.0"},"reference-count":19,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,3,24]],"date-time":"2015-03-24T00:00:00Z","timestamp":1427155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Health and Medical Research Council (NHMRC) of Australia","award":["535949"],"award-info":[{"award-number":["535949"]}]},{"DOI":"10.13039\/100008713","name":"Diabetes Australia Research Trust","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100008713","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001065","name":"Australian Diabetes Society","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001065","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>l-glutamine triggers glucagon-like peptide-1 (GLP-1) release from L cells in vitro and when ingested pre-meal, decreases postprandial glycaemia and increases circulating insulin and GLP-1 in type 2 diabetes (T2D) patients. We aimed to evaluate the effect of oral l-glutamine, compared with whole protein low in glutamine, on insulin response in  well-controlled T2D patients. In a randomized study with a crossover design, T2D patients (n = 10, 6 men) aged 65.1 \u00b1 5.8, with glycosylated hemoglobin (HbA1c) 6.6% \u00b1 0.7%  (48 \u00b1 8 mmol\/mol), received oral l-glutamine (25 g), protein (25 g) or water, followed by an intravenous glucose bolus (0.3 g\/kg) and hyperglycemic glucose clamp for 2 h. Blood was frequently collected for analyses of glucose, serum insulin and plasma total and active GLP-1 and area under the curve of glucose, insulin, total and active GLP-1 excursions calculated. Treatments were tested 1\u20132 weeks apart. Both l-glutamine and protein increased first-phase insulin response (p \u2264 0.02). Protein (p = 0.05), but not l-glutamine (p = 0.2), increased second-phase insulin response. Total GLP-1 was increased by both l-glutamine and protein (p \u2264 0.02). We conclude that oral l-glutamine and whole protein are similarly effective in restoring first-phase insulin response in T2D patients. Larger studies are required to further investigate the utility of similar approaches in improving insulin response in diabetes.<\/jats:p>","DOI":"10.3390\/nu7042101","type":"journal-article","created":{"date-parts":[[2015,3,24]],"date-time":"2015-03-24T13:07:25Z","timestamp":1427202445000},"page":"2101-2108","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["L-Glutamine and Whole Protein Restore First-Phase Insulin Response and Increase Glucagon-Like Peptide-1 in Type 2 Diabetes Patients"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9422-7852","authenticated-orcid":false,"given":"Dorit","family":"Samocha-Bonet","sequence":"first","affiliation":[{"name":"Diabetes & Metabolism Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst 2010, Sydney, NSW, Australia"},{"name":"Faculty of Medicine, UNSW Australia, High Street, Kensington 2052, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Don","family":"Chisholm","sequence":"additional","affiliation":[{"name":"Diabetes & Metabolism Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst 2010, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6853-3805","authenticated-orcid":false,"given":"Jens","family":"Holst","sequence":"additional","affiliation":[{"name":"NNF Center for Basic Metabolic Research, Department of Biomedical Sciences,  University of Copenhagen, Panum Institute, N\u00f8rregade 10, DK-1165 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jerry","family":"Greenfield","sequence":"additional","affiliation":[{"name":"Diabetes & Metabolism Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst 2010, Sydney, NSW, Australia"},{"name":"Faculty of Medicine, UNSW Australia, High Street, Kensington 2052, Sydney, NSW, Australia"},{"name":"Department of Endocrinology and Diabetes Center, St. Vincent's Hospital, 390 Victoria Street, Darlinghurst 2010, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1016\/j.cmet.2006.01.004","article-title":"The biology of incretin hormones","volume":"3","author":"Drucker","year":"2006","journal-title":"Cell Metab."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1409","DOI":"10.1152\/physrev.00034.2006","article-title":"The physiology of glucagon-like peptide 1","volume":"87","author":"Holst","year":"2007","journal-title":"Physiol. 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