Advisor Information
Dustin Slivka
Location
Dr. C.C. and Mabel L. Criss Library
Presentation Type
Poster
Start Date
3-3-2017 9:00 AM
End Date
3-3-2017 10:15 AM
Abstract
Environmental stimuli such as temperature and hypoxia can influence cellular signaling in the skeletal muscle. Previously we have reported no changes in gene expression related to mitochondrial development with acute exposure to normobaric hypoxia. However, exposure to hypobaric hypoxia may elicit different physiological responses. Purpose: To determine the response of skeletal muscle mitochondrial related gene expression after 4 h of exposure to normobaric normoxia (NN), normobaric hypoxia (NH), and hypobaric hypoxia (HH) after exercise. Methods: Recreationally trained participants (8 male, 7 female) each completed three trials of 1-h cycling at 70% of Wmax. Following exercise, participants sat in an environmentally controlled chamber for a 4-h recovery period in NN (975 m), NH (4,420 m), or HH (4,420 m) environmental conditions. Muscle biopsies were taken from the vastus lateralis pre-exercise and after a 4-h environmental exposure period. Samples were analyzed using qRT-PCR to assess gene expression related to mitochondrial development. Results: There were no differences in mRNA between trials or times in PGC-1α (p = 0.804), GABPA (p = 0.650), ERRα (p = 0.956), or NRF1 (0.563). TFAM mRNA increased in NH from pre-exercise to post-exercise (p = 0.036) and NH was higher compared to NN (p = 0.011) and but not HH (p = 0.053). Conclusion: These data indicate that gene expression related to mitochondrial development is only marginally affected (TFAM) by the type of hypoxic environment after a 4-h treatment despite differences in arterial oxygen saturation.
Effects of Normobaric and Hypobaric Hypoxia on Mitochondrial Related Gene Expression
Dr. C.C. and Mabel L. Criss Library
Environmental stimuli such as temperature and hypoxia can influence cellular signaling in the skeletal muscle. Previously we have reported no changes in gene expression related to mitochondrial development with acute exposure to normobaric hypoxia. However, exposure to hypobaric hypoxia may elicit different physiological responses. Purpose: To determine the response of skeletal muscle mitochondrial related gene expression after 4 h of exposure to normobaric normoxia (NN), normobaric hypoxia (NH), and hypobaric hypoxia (HH) after exercise. Methods: Recreationally trained participants (8 male, 7 female) each completed three trials of 1-h cycling at 70% of Wmax. Following exercise, participants sat in an environmentally controlled chamber for a 4-h recovery period in NN (975 m), NH (4,420 m), or HH (4,420 m) environmental conditions. Muscle biopsies were taken from the vastus lateralis pre-exercise and after a 4-h environmental exposure period. Samples were analyzed using qRT-PCR to assess gene expression related to mitochondrial development. Results: There were no differences in mRNA between trials or times in PGC-1α (p = 0.804), GABPA (p = 0.650), ERRα (p = 0.956), or NRF1 (0.563). TFAM mRNA increased in NH from pre-exercise to post-exercise (p = 0.036) and NH was higher compared to NN (p = 0.011) and but not HH (p = 0.053). Conclusion: These data indicate that gene expression related to mitochondrial development is only marginally affected (TFAM) by the type of hypoxic environment after a 4-h treatment despite differences in arterial oxygen saturation.