Investigating the Acute Effects of Increasing Alanine Exposure in Healthy Participants

January 9, 2026 updated by: Nicolai Jacob Wewer Albrechtsen

Investigating the Effect of Glucagon on Cognitive Function and Cerebral Glucose Metabolism in Humans: A Pilot Study

In this study the investigators will investigate the acute effects of increasing alanine exposure on metabolic parameters in healthy participants.

Participants will participate in one study day. After initial baseline blood samples, a three-hour intravenous infusion with glucagon will be initiated. The infusion rate will be increased every 30 minutes.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Two peripheral catheters will be placed in the antecubital vein of each arm for infusion of L-alanine and blood sampling respectively. The infusion rate of alanine will start at 1.4 μmol/kg/min and increase every 30 minutes over a 3-hour period, up to a maximum of 28 μmol/kg/min. The study day will last approximately 4 hours, and a maximal blood volume of 130 ml will be collected. Blood samples for the analysis of plasma glucagon, glucose, insulin, C-peptide etc. will be drawn every 15 minutes.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
15

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Capable of understanding the participant information and signing the consent form
  • Between 25 and 70 years of age at the time of screening
  • Body mass index (BMI) ≤ 25 kg/m2 at the time of screening

Exclusion Criteria:

  • Enrolment in other research projects that might interfere with the study
  • Diabetes diagnosis (type 1 and 2)
  • Pregnancy or breastfeeding
  • Use of medications which, in the opinion of the investigator, may jeopardise participant's safety or compliance with the protocol
  • Impaired liver function defined as either alanine aminotransferase (ALAT) and/or aspartate aminotransferase (ASAT) ≥ 2 times normal values
  • Kidney disease defined as serum creatinine levels ≥ 126 μmol/L for male and ≥ 111 μmol/L for female
  • Inadequately treated blood pressure at screening defined as repeated resting blood pressure outside the range 90-150 mmHg for systolic and 50-100 mmHg for diastolic
  • Active or recent malignant disease
  • Current or history of severe alcohol use or drug/chemical abuse as per investigator's judgement
  • Any chronic disorders or severe diseases which, in the opinion of the investigator, might jeopardise participant's safety or compliance with the protocol

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Alanine infusion
Other: alanine
A three-hour intravenous infusion with alanine with increasing infusion rate (from 1.4 μmol/kg/min and to 28 μmol/kg/min)

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Threshold alanine infusion rate for stimulation of plasma glucagon
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Lowest alanine infusion rate (µmol/kg/min) at which plasma glucagon concentration is significantly higher than baseline during a 3-hour stepwise alanine infusion (six 30-minute steps from 1.4 to 28 µmol/kg/min).
Baseline and every 30 minutes during the 0-180 min infusion period.

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Change in plasma glucose during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma glucose concentration (mmol/L) measured at baseline and every 30 minutes during a 3-hour stepwise alanine infusion (1.4-28 µmol/kg/min), analyzed as absolute values and change from baseline.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma follicle-stimulating hormone (FSH) during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma follicle-stimulating hormone (FSH) concentration (IU/L) measured at baseline and at the end of the 3-hour stepwise alanine infusion to explore acute effects on pituitary gonadotropin secretion.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma luteinizing hormone (LH) during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma luteinizing hormone (LH) concentration (IU/L) measured at baseline and at the end of the 3-hour stepwise alanine infusion to explore acute effects on pituitary gonadotropin secretion.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma cortisol during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma cortisol concentration (nmol/L) measured at baseline and every 60 minutes during the 3-hour stepwise alanine infusion to assess activation of the hypothalamic-pituitary-adrenal axis.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma triglycerides during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma triglyceride concentration (mmol/L) measured at baseline and at the end of the 3-hour stepwise alanine infusion to evaluate acute effects on lipid metabolism.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma urea during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma urea (carbamide) concentration (mmol/L) measured at baseline and at the end of the 3-hour stepwise alanine infusion to assess short-term effects on nitrogen metabolism.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma alanine aminotransferase (ALAT) during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma alanine aminotransferase (ALAT/ALT) activity (U/L) measured at baseline and at the end of the 3-hour stepwise alanine infusion to assess acute changes in liver enzyme levels.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma C-peptide during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma C-peptide concentration (pmol/L) measured at baseline and every 30 minutes during a 3-hour stepwise alanine infusion, analyzed as absolute values and change from baseline.
Baseline and every 30 minutes during the 0-180 min infusion period.
Change in plasma insulin during stepwise alanine infusion
Time Frame: Baseline and every 30 minutes during the 0-180 min infusion period.
Plasma insulin concentration (pmol/L) measured at baseline and every 30 minutes during a 3-hour stepwise alanine infusion, analyzed as absolute values and change from baseline.
Baseline and every 30 minutes during the 0-180 min infusion period.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Nicolai Jacob Wewer Albrechtsen

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Nicolai Jacob Wewer Albrechtsen, MD PhD, Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 20, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 30, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
January 20, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 9, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 9, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 20, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 20, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 9, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
December 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • GluCoMet_stepwise alanine

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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