Effects of Glutamine on GLP-1 and Insulin Secretion in Man

Study of the Effects of Glutamine on Glycemia, Glucagon-like Peptide-1 (GLP-1) and Insulin Secretion in Man

This study investigated the effect of glutamine, an amino acid, glycemia, glucagon-like peptide-1 (GLP-1) and insulin in participants with type 2 diabetes.

Study Overview

• Status: Completed
• Conditions: Type 2 Diabetes
• Intervention / Treatment: Drug: Sitagliptin; Drug: Placebo

Detailed Description

In this study, we investigated the effect of glutamine, an amino acid, on glycemia and on GLP-1 and insulin in participants with type 2 diabetes. Preliminary data published by our group suggests that glutamine is a strong determinant of GLP-1 secretion in vitro. We tested the hypothesis that glutamine lowers postprandial blood glucose and investigated whether the dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin modifies this effect.

• Study Type: Interventional
• Enrollment (Actual): 22
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • Sydney, New South Wales, Australia, 2010
      • Clinical Research Facility

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Type 2 diabetes, on metformin or diet alone (not sulphonylureas or insulin)

Exclusion Criteria:

• Malabsorption, renal or liver disease, treatment with steroids

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Glutamine+Sitagliptin; Glutamine 30 g/d (15 g with breakfast and dinner) + Sitagliptin	Drug: Sitagliptin; Glutamine 30g +sitagliptin 100mg; Other Names: Januvia
Placebo Comparator: Glutamine+Placebo; Glutamine 30 g/d (15 g with breakfast and dinner) + placebo	Drug: Placebo; Glutamine 30g +placebo (matching sitagliptin 100 mg)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postprandial Glucose Area Under the Curve (AUC)	The area under the curve (AUC) of the postprandial glucose following a meal challenge	0 to 180 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fructosamine	The blood concentration of the glycemic control marker fructosamine	4 weeks

Collaborators and Investigators

• Sponsor: Garvan Institute of Medical Research
• Investigators: Principal Investigator: Jerry R Greenfield, MD, PhD, Garvan Institute of Medical Research

Publications and helpful links

General Publications

• Samocha-Bonet D, Wong O, Synnott EL, Piyaratna N, Douglas A, Gribble FM, Holst JJ, Chisholm DJ, Greenfield JR. Glutamine reduces postprandial glycemia and augments the glucagon-like peptide-1 response in type 2 diabetes patients. J Nutr. 2011 Jul;141(7):1233-8. doi: 10.3945/jn.111.139824. Epub 2011 May 18.
• Samocha-Bonet D, Chisholm DJ, Holst JJ, Greenfield JR. L-glutamine and whole protein restore first-phase insulin response and increase glucagon-like peptide-1 in type 2 diabetes patients. Nutrients. 2015 Mar 24;7(4):2101-8. doi: 10.3390/nu7042101.
• Samocha-Bonet D, Chisholm DJ, Gribble FM, Coster AC, Carpenter KH, Jones GR, Holst JJ, Greenfield JR. Glycemic effects and safety of L-Glutamine supplementation with or without sitagliptin in type 2 diabetes patients-a randomized study. PLoS One. 2014 Nov 20;9(11):e113366. doi: 10.1371/journal.pone.0113366. eCollection 2014.

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2008
• Primary Completion (Actual): December 1, 2011
• Study Completion (Actual): November 1, 2014

Study Registration Dates

• First Submitted: May 6, 2008
• First Submitted That Met QC Criteria: May 6, 2008
• First Posted (Estimate): May 7, 2008

Study Record Updates

• Last Update Posted (Actual): May 13, 2019
• Last Update Submitted That Met QC Criteria: February 11, 2019
• Last Verified: February 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Hypoglycemic Agents; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Protease Inhibitors; Incretins; Dipeptidyl-Peptidase IV Inhibitors; Sitagliptin Phosphate
• Other Study ID Numbers: H07/059

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No