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Type 2 Diabetes MellitusNCT03223129

Insulin Sensitivity and Metabolomics During Oral Administration of Glucose and Graded Intravenous Infusion

A study testing Oral glucose tolerance test and Graded intravenous glucose infusion in people with Type 2 Diabetes Mellitus, run by Catholic University of the Sacred Heart at 1 site in Italy.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Bariatric surgery has been proven to be an effective treatment of type 2 diabetes and it has highlighted to role of the small intestine in glucose homeostasis. Improvement of glucose homeostasis occurs just a few days after the bariatric surgery, where parts of the small intestine is bypassed, has been performed. Read more about this study

Who is it for?
Ages 20 to 65 years
Conditions the study is for
Type 2 Diabetes Mellitus
What is being tested?
Oral glucose tolerance test and Graded intravenous glucose infusion
Could I receive a placebo?
No, everyone receives an active treatment
How many people
23 participants
Where
1 siteItaly
Study dates
9 Jan 2018to 31 Jan 2019
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 20 to 65 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Age between 20 and 65
  • BMI between 35 and 60 kg/m2
  • Ability to understand and comply with the study process.

Who cannot join

  • History of type 1 diabetes or secondary diabetes;
  • Previous bariatric surgery;
  • History of medical problems such as mental impairment;
  • Major cardiovascular disease;
  • Major gastrointestinal disease;
  • Major respiratory disease;
Show all 12Show fewer
  • Hormonal disorders;
  • Infection;
  • History of drug addiction and/or alcohol abuse;
  • Internal malignancy;
  • Pregnancy;
  • Suspected or confirmed poor compliance;

Trial locations and contacts

1 site in 1 country.

Italy1 site
  • Università Cattolica S. Cuore

    Roma

Other trials in Italy

About this study

Official title: Insulin Sensitivity and Metabolomics During Oral Administration of Glucose and a Graded Intravenous Infusion in Patients With Normal Glucose Tolerance, Impaired Glucose Tolerance and in Patients With Type 2 Diabetes Mellitus

Bariatric surgery has been proven to be an effective treatment of type 2 diabetes and it has highlighted to role of the small intestine in glucose homeostasis. Improvement of glucose homeostasis occurs just a few days after the bariatric surgery, where parts of the small intestine is bypassed, has been performed. Furthermore, conditioned medium from the duodenum and the jejunum from both diabetic rodents and humans are able to induce insulin resistance in normal mice and in myocytes. Hence the hypothesis is that the small intestine secretes factors that are able to induce insulin resistance.

This project aims to study how orally ingested glucose is able to induce insulin resistance and if this response differs in patients with normal glucose tolerance, impaired glucose tolerance and in patients with type 2 diabetes mellitus. To address this question glucose homeostasis will be studied by comparing whole body glucose uptake during a progressively increased oral glucose load with a graded glucose infusion where the blood glucose levels will be kept in the same range as during the oral glucose load in patients with normal glucose tolerance, impaired glucose tolerance and patients with type 2 diabetes mellitus.

Read more

Previous studied have shown that different metabolites and bile acids could be involved the regulation of glucose homeostasis. Hence, it is possible that the gut regulates metabolites that could be involved in small intestine-induced insulin resistance described above. The aim of this research is to study metabolomics in plasma collected during the oral glucose tolerance test with increasing load of glucose and the graded glucose infusion where plasma glucose level will be held in the same levels as during the oral glucose tolerance test and study the differences in patients with normal glucose tolerance, impaired glucose tolerance and in patients with type 2 diabetes mellitus.

The expected results in this study will demonstrate that the gut plays an important role in glucose homeostasis and that this system is dysregulated in type 2 diabetes. More importantly, novel factors derived or regulated from the gut that regulate insulin resistance and glucose tolerance will be identified which could be possible targets for future antidiabetic therapies.

Read the detailed description

The incidence of obesity and obesity-associated metabolic disorders such as insulin resistance and type 2 diabetes is increasing worldwide. To date, bariatric surgery is the only obesity treatment that results in long-term weight reduction. In addition, bariatric surgery has been reported to promote remission of type 2 diabetes and to be a more effective treatment than standard medication for type 2 diabetes. Surprisingly, improvement in glucose homeostasis after some bariatric surgery procedures occurs before weight loss is achieved. The mechanisms behind this improvement are still unclear but a recent study indicates that the bypassing of jejunum could play an important role in glucose homeostasis. Moreover, jejunum-derived proteins present in serum in both human and mice induce insulin resistance in cell cultures of myocytes and in mice. This taken together indicates that the gut may play an important role in glucose homeostasis in type 2 diabetes mellitus.

Metabolomics has recently been regarded to be one of the most suitable technologies for investigating complex diseases such as type 2 diabetes mellitus because it represent a real-time functional portrait of the organisms. Previous studies have shown that different metabolites and bile acids could be involved in the regulation of glucose homeostasis. Hence it is possible that the gut regulates metabolites that could be involved in the impaired glucose tolerance and type 2 diabetes mellitus.

The specific aims of this research project are:

Aim 1: To demonstrate that orally ingested glucose induces insulin resistance and to determine if this regulation of glucose homeostasis differs between subjects with normal glucose tolerance, impaired glucose tolerance and subjects with type 2 diabetes mellitus.

Aim 2: To identify metabolites regulated by the gut that are associated with impaired glucose tolerance and type 2 diabetes mellitus.

To address this aim, differences in glucose kinetics will be studied when glucose is orally administrated (in an oral glucose tolerance test, OGTT) compared to an graded intravenous glucose infusion, were plasma glucose levels are held in the same range as during the OGTT, in subjects with normal glucose tolerance (n = 8), impaired glucose tolerance (n = 8) and type 2 diabetes mellitus (n = 8).

Basal glucose kinetics will first be assessed by double glucose tracer technique. In the basal part of the glucose tolerance tests glucose tracer nr 1 will be infused and then be followed by either a continued infusion and a gradually increasing oral glucose load (25 g, 75 g and 125 g with a 2 h interval during the OGTT) with glucose tracer nr 2 or an graded intravenous glucose tracer infusion where plasma glucose levels are adjusted to those obtained during the OGTTs.

Gas chromatography/mass spectrometry will be used to measure isotopic enrichment of glucose tracers. Insulin, glucagon, total glucagon-like peptide 1 (GLP-1) and C-peptide will be measured by radioimmunoassays repeatedly during the glucose tolerance tests. Glucose kinetics including endogenous glucose production, insulin sensitivity and insulin secretion will be calculated. Differences in glucose kinetics between the oral and intravenous administration of glucose will be calculated and compared in subjects with normal glucose tolerance, impaired glucose tolerance or type 2 diabetes mellitus.

Analysis of metabolomics will be performed in plasma collected during the OGTT and the graded intravenous glucose infusion. Metabolites in plasma samples will be analyzed using two global profiling analytical platforms and a targeted profiling platform. Two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-TOFMS) will be performed to measure small polar metabolites. Molecular lipids will be assessed by a global platform using ultra performance liquid chromatography coupled to quadrupole-TOFMS (UPLC-QTOFMS). A targeted platform based on UPLC coupled to triple-quadrupole MS (UPLC-QqQMS) will be performed to quantify both unconjugated and conjugated forms of bile acids.

Differences in plasma metabolites during OGTT and graded intravenous glucose infusion will be studied to assess information on possible regulation by the gut and the results will be compared in subjects with normal glucose tolerance, impaired glucose tolerance and subjects with type 2 diabetes mellitus.

Significance The expected results in this study will demonstrate that the gut plays an important role in glucose homeostasis and that this system is dysregulated in type 2 diabetes. More importantly, novel factors derived or regulated from the gut that regulate insulin resistance and glucose tolerance will be identified which could be possible targets for future antidiabetic therapies.

Being tested
Oral glucose tolerance test, Graded intravenous glucose infusion
Keywords
Type 2 Diabetes Mellitus, Impaired glucose tolerance, Metabolomics
Medical subject headings
Diabetes Mellitus, Type 2, Glucose Intolerance

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Oral glucose tolerance testOther

    Oral glucose tolerance tests were glucose is administrated orally with an increasing load (25g, 75g, 100 g)

  • Graded intravenous glucose infusionOther

    Graded intravenous glucose infusion where glucose is infused in order to receive an plasma glucose pattern comparable to those received during the oral glucose tolerance tests.

Study groups in NCT03223129
Study groupRoleWhat they receive
Patients with normal glucose toleranceOtherPatients included in this arm will have a plasma glucose below 140 mg/dl after a 2 h oral glucose tolerance test with a glucose load of 75 g. All patients in this arm will undergo oral glucose tolerance test with increasing glucose load and a graded intravenous glucose infusion were plasma glucose levels are held at the same level as during the oral glucose tolerance test.
Receives: Other: Oral glucose tolerance test; Other: Graded intravenous glucose infusion
Patients with impaired glucose toleranceOtherPatients included in this arm will have a plasma glucose between 140 mg/dl to 199 mg/dl after a 2 h oral glucose tolerance test with a glucose load of 75 g. All patients in this arm will undergo oral glucose tolerance test with increasing glucose load and a graded intravenous glucose infusion were plasma glucose levels are held at the same level as during the oral glucose tolerance test.
Receives: Other: Oral glucose tolerance test; Other: Graded intravenous glucose infusion
Patients with type 2 diabetes mellitusOtherPatients included in this arm will have a plasma glucose above 200 mg/dl after a 2 h oral glucose tolerance test with a glucose load of 75 g. All patients in this arm will undergo oral glucose tolerance test with increasing glucose load and a graded intravenous glucose infusion were plasma glucose levels are held at the same level as during the oral glucose tolerance test.
Receives: Other: Oral glucose tolerance test; Other: Graded intravenous glucose infusion

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Glucose kinetics

    Whole body glucose uptake will be measured using a double glucose tracer technique during both the oral glucose tolerance test and the graded intravenous glucose infusion.

    Measured: 1 year

Secondary outcomes (1)
  1. Metabolomics

    Plasma levels of small polar metabolites, molecular lipids and conjugated and unconjugated bile acids will be measured during both oral glucose tolerance test and during the graded intravenous glucose infusion.

    Measured: 1 year

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted19 Jul 2017
  2. Study start9 Jan 2018
  3. Primary completion31 Jan 2019
  4. Study completion31 Jan 2019

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Non-randomised
Intervention model
Parallel groups
Model description
Patients with either normal glucose tolerance, impaired glucose tolerance or with diagnosed type 2 diabetes mellitus will undergo oral glucose tolerance tests with an increasing load of glucose and thereafter isoglycemic intravenous glucose infusion.
Masking
None (open label)
Enrolment
23 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03223129
Sponsor's protocol ID
U911/14
Status last verified
Jul 2019
First submitted
12 Jun 2017
Last updated
26 Jul 2019
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Mingrone G, Panunzi S, De Gaetano A, Ahlin S, Spuntarelli V, Bondia-Pons I, Barbieri C, Capristo E, Gastaldelli A, Nolan JJ. Insulin sensitivity depends on the route of glucose administration. Diabetologia. 2020 Jul;63(7):1382-1395. doi: 10.1007/s00125-020-05157-w. Epub 2020 May 8.

    PubMed 32385603

Questions about this trial

What is this clinical trial studying?

A study testing Oral glucose tolerance test and Graded intravenous glucose infusion in people with Type 2 Diabetes Mellitus, run by Catholic University of the Sacred Heart at 1 site in Italy.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 26 Jul 2019. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Glucose kinetics (time frame: 1 year). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03223129, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Jul 2019.

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