Human Solute Carrier Family 5 Member 2 (SLC5A2) Deficiency and the Glucagon-Incretin Axis

Cardiovascular Diseases Clinical Trial

Official title:

Human SLC5A2 Deficiency and the Glucagon-Incretin Axis: A Pilot Study

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03965000
• Other study ID #: 20190121-1930
• Status: Recruiting
• Start date: January 24, 2019
• Est. completion date: January 2022

Study information

• Verified date: May 2019
• Source: Medical University Innsbruck
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Sodium-glucose-cotransporter 2 (SGLT2) are a new type of oral antidiabetic drugs. SGLT2 inhibitors increase the urinary glucose excretion and thereby decrease blood glucose levels. Beside their glucose lowering effects SGLT2 inhibitors showed beneficial effects on the cardiovascular health. But several studies in cell culture and mice showed that the physiological inhibition of glucagon after meal consumption is impaired when using SGLT2 inhibitors.

The patients carry a rare genetical disease called Familial renal glucosuria (FRG), a human model of life long SGLT2 inhibition. To elucidate the effects of partial and complete SGLT2 inhibition in humans the investigators perform a mixed-meal tolerance test (MMTT), the gold standard for elucidation of insulin and glucagon dynamics.

Description:

The index patient was referred to the Department of Internal Medicine I at the Medical University of Innsbruck for evaluation of unclear glucosuria in combination with normal blood glucose levels. The patient suffered from recurrent urinary tract infections and increased urinary frequency, showed a physiological hemoglobin A1c and no further signs of renal dysfunction. Sequencing of the SLC5A2 coding region confirmed that the patient was compound heterozygous for two SLC5A2 mutations. The patient is a mother of five healthy children which are willing to take part in the test. The children show a 50/50 distribution of the mother's mutations. The MMTT will take place after 48 hours of alcohol, sport abstinence and an overnight fasting period. The patients will be given 6 ml/kg body weight of a standardized liquid meal. Blood samples will be collected 10 minutes before consumption of the meal, at the time point of consumption and 15, 30, 60, 120, 150, 180, 210 and 240 minutes after consumption. At each time point six blood tubes will be taken, except at time point -10 and 240 minutes, there is one sample more collected. The investigators aim to assess glucagon, insulin, c-peptide, gastric inhibitory polypeptide (GIP), Glucagon-like peptide-1 (GLP-1), Glucagon-like peptide-2 (GLP-2) levels.

Glucose tolerance will be assessed by using the 4 hours area under the curve (AUC) for glucose. To evaluate the beta-cell function the 4h-AUC's for insulin, c-peptide and the 4h-AUC insulin:glucose ratio will be calculated and compared. The calculation of the alpha-cell function will be performed with the AUC of glucagon and the AUC glucagon/glucose ratio. GIP, GLP-1 and GLP-2 will be determined using the AUC. The AUC's will be calculated by the trapezoidal method.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 10
• Est. completion date: January 2022
• Est. primary completion date: January 2021
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 80 Years

Eligibility

Inclusion Criteria:

• At least 18 years

• Capable of giving consent

• One or more SLC5A2 mutations leading to FRG

• Written consent

Exclusion Criteria:

• Impaired glucose tolerance

• Diabetes mellitus

Related Conditions & MeSH terms

• Cardiovascular Diseases
• Diabetes Mellitus
• Familial Renal Glucosuria

Intervention

Other:
• Mixed-meal-tolerance-test
To assess the dynamics of the glucagon-incretin axis we need to perform the MMTT. Thereby the patients need to consume a body weight adjusted, standardized meal and we draw blood at fixed time points over 4 hours.

Locations

Country	Name	City	State
Austria	Medical University Innsbruck	Innsbruck	Tyrol

Sponsors (1)

Lead Sponsor	Collaborator
Medical University Innsbruck

Country where clinical trial is conducted

Austria, 

References & Publications (6)

Bonner C, Kerr-Conte J, Gmyr V, Queniat G, Moerman E, Thévenet J, Beaucamps C, Delalleau N, Popescu I, Malaisse WJ, Sener A, Deprez B, Abderrahmani A, Staels B, Pattou F. Inhibition of the glucose transporter SGLT2 with dapagliflozin in pancreatic alpha cells triggers glucagon secretion. Nat Med. 2015 May;21(5):512-7. doi: 10.1038/nm.3828. Epub 2015 Apr 20. — View Citation

Ferrannini E, Muscelli E, Frascerra S, Baldi S, Mari A, Heise T, Broedl UC, Woerle HJ. Metabolic response to sodium-glucose cotransporter 2 inhibition in type 2 diabetic patients. J Clin Invest. 2014 Feb;124(2):499-508. doi: 10.1172/JCI72227. Epub 2014 Jan 27. Erratum in: J Clin Invest. 2014 Apr 1;124(4):1868. — View Citation

Pedersen MG, Ahlstedt I, El Hachmane MF, Göpel SO. Dapagliflozin stimulates glucagon secretion at high glucose: experiments and mathematical simulations of human A-cells. Sci Rep. 2016 Aug 18;6:31214. doi: 10.1038/srep31214. — View Citation

Rosenstein R, Hough A. Empagliflozin, Cardiovascular Outcomes, and Mortality in Type 2 Diabetes. N Engl J Med. 2016 Mar 17;374(11):1093-4. doi: 10.1056/NEJMc1600827. — View Citation

Zinman B, Lachin JM, Inzucchi SE. Empagliflozin, Cardiovascular Outcomes, and Mortality in Type 2 Diabetes. N Engl J Med. 2016 Mar 17;374(11):1094. doi: 10.1056/NEJMc1600827. — View Citation

Zinman B, Wanner C, Lachin JM, Fitchett D, Bluhmki E, Hantel S, Mattheus M, Devins T, Johansen OE, Woerle HJ, Broedl UC, Inzucchi SE; EMPA-REG OUTCOME Investigators. Empagliflozin, Cardiovascular Outcomes, and Mortality in Type 2 Diabetes. N Engl J Med. 2015 Nov 26;373(22):2117-28. doi: 10.1056/NEJMoa1504720. Epub 2015 Sep 17. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in the glucagon-incretin axis.	Glucose tolerance will be assessed by using the 4 hours area under the curve (AUC) for glucose.; Beta-cell function will be assessed by the 4h-AUC's for insulin, c-peptide and the 4h-AUC insulin:glucose ratio will be calculated and compared. The calculation of the alpha-cell function will be performed with the AUC of glucagon and the AUC glucagon/glucose ratio. GIP, GLP-1 and GLP-2 will be determined using the AUC. The AUC's will be calculated by the trapezoidal method	18 months
Primary	Changes in the gene expression	By collecting blood samples for gene expression analysis before and after the test and comparing it to our healthy controls.	18 months