Day-Night Rhythm in Human Skeletal Muscle

Not Applicable

Completed

• Conditions: Insulin Resistance; Diabetes Mellitus, Type 2
• Interventions: Other: Standardized living protocol

• Registration Number: NCT02261168
• Lead Sponsor: Maastricht University Medical Center

Brief Summary

This study evaluates the existence of a day-night rhythm in skeletal muscle energy metabolism in healthy lean subjects. Subjects will stay at the research facility for 44 hours with a standardized living protocol during which several measurements of skeletal muscle and whole body energy metabolism will be performed.

Detailed Description

Recent evidence from both observational and experimental studies indicates that disobeying our normal day-night rhythm negatively influences our metabolic and cardiovascular health, possibly leading to obesity and type 2 diabetes mellitus (T2DM). An important hallmark of obesity and T2DM is a decreased skeletal muscle mitochondrial function. Interestingly, recent research indicates that also skeletal muscle mitochondrial function under the influence of a day-night rhythm. The main objective of this study is to investigate the presence of a day-night rhythm in skeletal muscle energy metabolism (in particular mitochondrial function) of healthy young participants. Therefore, subjects will stay at the research unit for 44 hours, with standardized meals and sleeping time. During this period we will take five muscle biopsies, perform indirect calorimetry measurements and blood draws.

Study Timeline

• Study First Submitted: 2014-09-24
• Study First Submitted QC: 2014-10-06
• Study First Posted: 2014-10-10
• Study Start: 2014-11
• Primary Completion: 2015-07
• Study Completion: 2015-07
• Status Verified: 2015-09
• Last Update Submitted: 2015-09-04
• Last Update Posted: 2015-09-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 12

Inclusion Criteria

• Caucasian
• Healthy (as determined by dependent physician based on medical questionnaire)
• Male
• Age: 18-35 years
• Normal BMI (18-25 kg/m2)
• Regular sleeping time (normally 7-9h daily)

Exclusion Criteria

• Extreme early bird or extreme night person (score ≤30 or ≥70 on MEQ-SA questionnaire)
• Heavily varying sleep-wake rhythm
• Shiftwork during last 3 months
• Travel across >1 time zone in the last 3 months
• Engagement in exercise > 2 hours total per week
• Using >400mg caffeine daily
• Smoking
• Unstable body weight (weight gain or loss > 3kg in the last 3 months)
• Significant food allergies/intolerance (seriously hampering study meals)
• Participation in another biomedical study within 1 month before the first study visit
• Any contra-indication to Magnetic Resonance Imaging (MRI) scanning

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Standardized living protocol	Standardized living protocol	Subjects are kept at the research facility to adhere to a standardized living protocol, mimicking a normal daily living situation. During the study, multiple tests will be performed, including muscle biopsies, blood draws, MRS measurements and indirect calorimetry.

Primary Outcome Measures

Name	Time	Method
Day-night rhythm in skeletal muscle mitochondrial respiration	40 hours.	O2-flux (pmol/mg/s) measured with high resolution respirometry upon administration of different substrates

Secondary Outcome Measures

Name	Time	Method
Day-night rhythm in whole-body energy metabolism	40 hours.	Energy expenditure (kJ/min), glucose oxidation (g/min) and fat oxidation (g/min) measured by indirect calorimetry
Day-night rhythm of in markers of normal day-night rhythm (cortisol, melatonin, core body temperature)	measured during the 2nd study day	Blood cortisol and melatonin levels and core body temperature measured by an ingested telemetric pill.
Day-night rhythm in muscle DNA, mRNA and protein levels of markers involved in molecular clock and mitochondrial metabolism.	40 hours.	Quantify mRNA and protein levels by qPCR or micro-array and Western blots
Change in liver volume and liver lipid concentration during the day	First study day 6 PM, second study day 7 AM	Measured by Magnetic Resonance Imaging and -Spectroscopy (MRI/MRS). Lipid signals in the MRS spectra will be quantified while suppressing the strong water signal in the region of interest (right liver lobe)
Day-night rhythm in blood metabolic compounds (e.g. glucose, insulin, FFA's, cholesterol)	measured during the 2nd study day
Day-night rhythm of molecular clock mRNA and protein levels in blood PBMC's	measured during the 2nd study day	Measured by qPCR and Western Blots

Trial Locations

Locations (1)

Maastricht University; 🇳🇱 Maastricht, Netherlands