The Effect of Lifestyle-induced Hepatic Steatosis on Glucagon-stimulated Amino Acid Turnover

Many patients with type 2 diabetes exhibit elevated plasma concentrations of the glucose-mobilising pancreatic hormone glucagon; i.e. hyperglucagonaemia. This contributes to the hyperglycaemic state of the patients and is considered an important component in the pathophysiology of type 2 diabetes; but the mechanisms underlying this phenomenon remain unclear. The liver constitutes the main target organ of glucagon, and studies have shown that hyperglucagonaemia goes hand in hand with hyperaminoacidaemia and that both are associated with non-alcoholic fatty liver disease (NAFLD), independently of the presence of type 2 diabetes. In line with this, several recent studies support the existence of a feedback-cycle between the liver and the pancreatic alpha cells, governed by circulating glucagon and amino acids. The investigators hypothesise that the presence of hepatic steatosis results in hepatic glucagon resistance at the level of amino acid turnover, i.e. impaired glucagon-induced suppression of circulating amino acid concentrations. If this hypothesis proves correct, it would establish build-up of fat in the liver as a core mechanism underlying hyperglucagonaemia and, since the hyperglucagonemia is at least partly responsible for the fasting hyperglycaemia, as an important contributor to the hyperglycaemia of type 2 diabetes.

Study Overview

• Status: Completed
• Conditions: Non-Alcoholic Fatty Liver Disease; Glucagon Resistance
• Intervention / Treatment: Drug: Glucagon

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Malte P Suppli, MD; Phone Number: 25151436; Email: malte.palm.suppli@regionh.dk

Study Locations

• Denmark
  • Copenhagen
    • Hellerup, Copenhagen, Denmark, 2900
      • Center for Clinical Metabolic Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Normal fasting plasma glucose and glycated haemoglobin (HbA1c) <42 mmol/mol
• Body mass index (BMI) between 18.5 and 25 kg/m2
• Haemoglobin >8.3 mmol/l
• Habitual diet in accordance with the Nordic Nutrition Recommendations
• Age between 20 and 65 years
• Oral and written informed consent

Exclusion Criteria:

• Diabetes
• First-degree relatives with diabetes
• Fasting plasma triacylglycerol indicating dyslipidemia (≥2 mmol/l)
• Nephropathy (estimated glomerular filtration rate (eGFR) <60 ml/min and/or microalbuminuria with an albumin to creatinine ratio of 30-300 μg/mg)
• Known liver disease and/or alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) >2 × normal values
• Signs of liver fibrosis and/or steatosis evaluated by FibroScan (CAP value >2380 dB/m and/or kPa >65.0) and/or FIB-4 score (>1.45)
• >5% steatosis evaluated by MRI carried out before experimental Day A (see Methods)
• Use of medication
• Use of dietary protein supplementation or any other dietary supplements that cannot be paused during participation
• Excessive training habits, defined as >2 weekly strength and/or aerobic training sessions
• Pregnancy and/or breastfeeding
• Implanted metal objects incompatible with magnetic resonance imaging (MRI)
• Any condition that the investigator feels would interfere with trial completion

Study Plan

How is the study designed?

Design Details

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

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Healthy Participants; 20 healthy participants included in the arm for 3 experimental days each. On each experimental day infusions of stable isotope glucose (0,6 micromol/kg/min), glucagon (1 hour low; 0,6 ng/kg/min, 2 hours high; 4,0 ng/kg/min), somatostatin (450 micrograms/hour) and insulin (0,1 mU/kg/min) will be administered. Between the first two experimental days the participants will follow a sedentary lifestyle combined with a high-calorie diet intervention

Drug: Glucagon; Pancreatic clamp; Other Names: Insulin; Somatostatin; 6,6 H2-glucose

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Nadir of the total amino acid concentration during a two-hour high physiological glucagon infusion during a pancreatic clamp with somatostatin	micromol/liter	depending on the nadir between time 60 minutes and time 180 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
average slope of the curve describing the change in the total amino acid concentration during 'supraphysiological' glucagon infusion	micromol/liter/minute	between time 60 minutes and time 180 minutes
the incremental area under the curve (iAUC) for total amino acid concentrations during 'supraphysiological' glucagon infusion	micromol/liter	between time 60 minutes and time 180 minutes
the percentage change in amino acid concentration during the last hour of the 'supraphysiological' glucagon infusion as assessed by baseline subtracted AUC	micromol/liter	between time 60 minutes and time 180 minutes

Collaborators and Investigators

• Sponsor: Malte Palm Suppli, MD
• Collaborators: Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark; Clinical Metabolomics Core Facility, Department of Clinical, Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Department of Biomedical Sciences & NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health, and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

Study record dates

Study Major Dates

• Study Start (Actual): February 8, 2021
• Primary Completion (Actual): December 9, 2021
• Study Completion (Actual): December 9, 2021

Study Registration Dates

• First Submitted: April 21, 2021
• First Submitted That Met QC Criteria: April 21, 2021
• First Posted (Actual): April 26, 2021

Study Record Updates

• Last Update Posted (Estimate): May 11, 2023
• Last Update Submitted That Met QC Criteria: May 10, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Digestive System Diseases; Liver Diseases; Fatty Liver; Non-alcoholic Fatty Liver Disease; Physiological Effects of Drugs; Gastrointestinal Agents; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Glucagon; Somatostatin
• Other Study ID Numbers: SIRG-2

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No