The Role of TBC1D4 in Exercise- and Insulin-induced Glucose Metabolism in Human Skeletal Muscle

NCT04170972 | Completed

• 5 other identifiers: KVUG 2016-12H-18007316130575053-00095B28136
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

Recently a common Greenlandic nonsense p.Arg684erTer variant (in which arginine is replaced by a termination codon) in the gene TBC1D4 was discovered. The variant has an allele frequency of 17%. Homozygous carriers of this TBC1D4 variant have impaired glucose tolerance and a 10-fold enhanced risk of developing type 2 diabetes (T2D). The investigators propose to carry out comprehensive metabolic phenotyping of adult Inuits carrying zero or two alleles of the TBC1D4 variant. The investigators hypothesise that regulation of TBC1D4 in skeletal muscle is pivotal in regulating glucose uptake during exercise, during physiological insulin stimulation, and for the ability of an acute bout of exercise to improve insulin sensitivity to regulate glucose metabolism in humans. The overall aims in the present project are to:

1. 1.Determine whether the TBC1D4 p.Arg684Ter variant affects the regulation of glucose uptake in skeletal muscle during exercise and during physiological insulin stimulation.
2. 2.Determine the effect of the TBC1D4 p.Arg684Ter variant for the ability of acute exercise to insulin sensitize skeletal muscle to regulate glucose metabolism.
3. 3.Define the metabolic pathways affected by the p.Arg684Ter variant in order to identify causal factors responsible for the diabetic phenotype of Inuit carriers.

Conditions

Exercise; Insulin Sensitivity; Skeletal Muscle

Outcome Measures

Primary Outcomes (9)

• Changes in leg glucose uptake

  Leg glucose uptake is calculated by the arterial-venous difference i blood glucose concentration multiplied with leg blood flow. Sampling of artery and venous blood samples for blood glucose measurements. Measures of artery blood flow by Ultrasound Doppler technique allows a final calculation of glucose uptake across the legs before exercise, during exercise, in recovery from exercise and with insulin stimulation.

  Measured 14 times during the experimental day (dispersed over 6 hours)

• Changes in whole body insulin sensitivity sensitivity.

  Insulin stimulated glucose uptake at whole body level (glucose infusion rate)

  6 times (each 20 minutes) during 2 hours insulin stimulation.

• Metabolome.

  Metabolomic analyses to map changes in biochemical pathways in skeletal muscle.

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Transcriptome.

  Transcriptome sequencing in skeletal muscle.

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Changes in the TBC1D4 interactome.

  TBC1D4 interactome analyses, to identify TBC1D4 signaling partners

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Proteome and phosphoproteome.

  Proteomics and targeted phosphoproteomic to identify changes in skeletal muscle.

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Changes in phosphorylation and glycosylation signatures of TBC1D4

  Phosphorylation and glycosylation signatures of the TBC1D4 protein by western blotting to describe regulation of TBC1D4.

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Changes of canonical intermediates in insulin- and exercise-induced signaling

  Expression and/or activity of canonical intermediates in insulin- and exercise-induced signaling and metabolic pathways.

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

• Changes in leg substrate utilization

  Throughout the study day sampling of artery and venous blood/plasma samples allow estimation of substrate utilization based on the respiratory quotient (RQ).

  At 4 times points: Before exercise, immediately after exercise, 3 hours after exercise and after 2 hours of insulin stimulation.

Secondary Outcomes (2)

• Substrate metabolism in primary myotubes from TBC1D4 p.Arg684 variant carriers and controls

  At two conditions: With and without insulin.

• Activities of key enzymes in glucose and fat metabolism

  at 2 time points: Before and after 2 hours of insulin stimulation.

Study Arms (2)

Exercise and vivo insulin stimulation in TBC1D4 gene-variants

EXPERIMENTAL

Acute exercise and in vivo insulin stimulation in homozygote carriers of a p.ARg684T TBC1D4 gene-variant.

Other: Acute exercise

Exercise and vivo insulin stimulation in matched controls

EXPERIMENTAL

Acute exercise and in vivo stimulation in none carriers (matched controls) of the p.Arg684T TBC1D4 gene-variant.

Other: Acute exercise

Interventions

Acute exercise OTHER

One hour of acute one-legged knee-extensor exercise followed by 3 hours recovery and 2 hours insulin (1.5 mU/min/kg) stimulation.

Also known as: Insulin stimulation

Exercise and vivo insulin stimulation in TBC1D4 gene-variants; Exercise and vivo insulin stimulation in matched controls

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Homozygote carriers of a pArg684T gene-variant (cases) and matched non carriers (controls)
• BMI between 20-35 kg/m2

You may not qualify if:

• Medical treated type 2 diabetes patients

Sponsors & Collaborators

• University of Copenhagen: lead

Study Sites (1)

Department of Exercise, Nutrition and Sports, Faculty of Sciences, University of Copenhagen

Copenhagen, 2100, Denmark

Location

Related Publications (1)

• Moltke I, Grarup N, Jorgensen ME, Bjerregaard P, Treebak JT, Fumagalli M, Korneliussen TS, Andersen MA, Nielsen TS, Krarup NT, Gjesing AP, Zierath JR, Linneberg A, Wu X, Sun G, Jin X, Al-Aama J, Wang J, Borch-Johnsen K, Pedersen O, Nielsen R, Albrechtsen A, Hansen T. A common Greenlandic TBC1D4 variant confers muscle insulin resistance and type 2 diabetes. Nature. 2014 Aug 14;512(7513):190-3. doi: 10.1038/nature13425. Epub 2014 Jun 18.

  PMID: 25043022 BACKGROUND

MeSH Terms

Conditions

Motor Activity; Insulin Resistance

Interventions

Exercise

Condition Hierarchy (Ancestors)

Behavior; Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: A case-control study with two groups of participants with different genetic background on the TBC1D4 gene: 1. Homozygote carriers of a p.Arg684T TBC1D4 gene-variant 2. None carriers (matched controls) of the p.Arg684T TBC1D4 gene-variant

Study Record Dates

• First Submitted: April 23, 2019
• First Posted: November 20, 2019
• Study Start: October 17, 2017
• Primary Completion: May 1, 2019
• Study Completion: September 1, 2019
• Last Updated: January 6, 2022

Record last verified: 2021-04

Locations

DK (1)