Mitochondrial Biogenesis
Conditions
Brief summary
This study examines the impact of exercise intensity on the 12-hour time-course of mitochondrial biogenic gene and protein expression in human skeletal muscle. Briefly, participants will perform two experimental sessions involving an acute bout of work-matched low- or high-intensity interval cycling exercise in a randomized crossover fashion, two weeks apart. Skeletal muscle biopsies will be obtained from the vastus lateralis (3 from each leg) before and 1, 3, 6, 9, and 12 hours post-exercise. Changes in the expression of various transcription factors and mitochondrial proteins will be examined at the mRNA and protein level to determine the time-course of changes in these factors differs between exercise protocols of different intensities.
Interventions
OTHERLO
Participants will perform an acute bout of low-intensity cycling (11 x 1 min intervals at \ 73% of peak aerobic work rate interspersed with 1 min recovery periods)
OTHERHI
Participants will perform an acute bout of high-intensity cycling (8 x 1 min intervals at \ 100% of peak aerobic work rate interspersed with 1 min recovery periods)
Sponsors
Brendon Gurd, PhD
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
MALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* recreationally active (no more than three hours of structured weekly physical activity) * not currently involved in a systematic training program for improving cardiorespiratory fitness, muscular strength, and/or sport-specific skills * body mass index \< 30 kg/m2
Exclusion criteria
* presence of cardiometabolic disease * taking regular prescription medication for the treatment of cardiometabolic disease * current cigarette smoker
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in peroxisome proliferator activated receptor (PPAR) gamma co-activator 1-alpha (PGC-1α) messenger ribonucleic acid (mRNA) expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | PGC-1α gene expression (indirect indicator of PGC-1α activity). Transcriptional co-activator involved in the control of mitochondrial biogenesis. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in nuclear factor-erythroid 2 like 2 (Nrf2) mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | Nrf2 gene expression (indirect indicator of Nrf2 activity). Transcription factor involved in the control of mitochondrial biogenesis. |
| Change in Nrf2 protein content | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | Nrf2 protein content |
| Change in PPAR-beta mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | PPAR-beta gene expression (indirect indicator of PPAR-beta activity). Transcription factor involved in the control of mitochondrial biogenesis. |
| Change in estrogen related receptor (ERR)-gamma mRNA expression | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | ERR-gamma gene expression. Transcription factor involved in the control of mitochondrial biogenesis. |
| Change in leucine-rich pentatricopeptide repeat containing protein 130 (LRP130) mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | LRP130 gene expression. Transcriptional co-activator and RNA-binding protein involved in the transcriptional control and stabilization of mitochondrial mRNAs |
| Change in LRP130 protein content | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | LRP130 protein content |
| Change in nuclear respiratory factor-1 (NRF-1) mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | NRF-1 gene expression. Transcription factor involved in the control of mitochondrial biogenesis. |
| Change in NRF-1 protein content | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | NRF-1 protein content |
| Change in mitochondrial transcription factor A (TFAM) mRNA expression | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | TFAM gene expression. Transcription factor controlling the expression of mitochondrial-encoded genes. |
| Change in TFAM protein content | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | TFAM protein content |
| Change in PGC-1α protein content | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | PGC-1α protein content |
| Change in cytochrome c oxidase subunit 4 (COXIV) mRNA expression. | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | COXIV gene expression. Nuclear encoded subunit of the electron transport chain complex 4 (COX) |
| Change in COXI mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | COXI gene expression. Mitochondrial encoded subunit of the electron transport chain complex IV (COX) |
| Change in COXII mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | COXII gene expression.Mitochondrial encoded subunit of the electron transport chain complex IV (COX). |
| Change in nicotinamide adenine dinucleotide (NADH) subunit 1 (ND1) mRNA expression | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | ND1 gene expression. Mitochondrial encoded subunit of the electron transport chain complex 1 (NADH dehydrogenase) |
| Change in ND4 mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | ND4 gene expression. Mitochondrial encoded subunit of the electron transport chain complex 1 (NADH dehydrogenase). |
| Change in citrate synthase (CS) mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | CS gene expression. The first rate limiting enzyme of the Kreb's cycle. |
| Change in NRF-2 mRNA expression | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | NRF-2 gene expression. Transcription factor involved in the control of mitochondrial biogenesis. |
| Change in mitochondrial transcription factor B1 (TFB1M) mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | TFB1M gene expression. Transcription factor controlling the expression of mitochondrial-encoded genes. |
| Change in mitochondrial transcription factor B2 (TFB2M) mRNA expression | before exercise and 1, 3, 6, 9, and 12 hours post-exercise | TFB2M gene expression. Transcription factor controlling the expression of mitochondrial-encoded genes. |
| Change in p53 mRNA expression | before exercise to 1, 3, 6, 9, and 12 hours post-exercise | p53 gene expression. Transcription factor involved in the control of mitochondrial biogenesis. |
Countries
Canada
Contacts
Primary ContactHashim Islam, MSc
Outcome results
None listed