Role of PGC-1α in fiber type conversion in the palatopharyngeus muscle of OSA patients

J Clin Lab Anal. 2022 Jul;36(7):e24551. doi: 10.1002/jcla.24551. Epub 2022 Jun 12.

Abstract

Background: Obstructive sleep apnea (OSA) has a high incidence and is harmful to health. It is characterized by repeated collapse of the upper airway. However, the mechanism underlying upper airway collapse is unclear.

Methods: Patients with OSA and chronic tonsillitis were studied. Pathological changes in palatopharyngeus muscle were detected. The expression of peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α) and nuclear respiratory factor-1 (NRF-1) in muscles was detected by PCR and Western blotting. Immunofluorescence staining was used to detect the expression of type I and type II myofibril.

Results: The structure of the palatopharyngeus muscle was changed, and the expression of PGC-1α and NRF-1 was decreased in the OSA group compared with that in the control group. The expression of PGC-1α, NRF-1, and type I myofibril in C2C12 myoblasts was decreased by intermittent hypoxia exposure. The expression of type I myofibril was decreased when knocking down PGC-1α.

Conclusion: OSA patients exhibited pathological damage in palatopharyngeus muscle. PGC-1α was involved in the fiber type conversion in palatopharyngeus muscle caused by intermittent hypoxia.

Keywords: OSA; PGC-1α; intermittent hypoxia; skeletal muscle fiber type.

MeSH terms

  • Humans
  • Hypoxia
  • Nuclear Respiratory Factor 1* / metabolism
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha* / metabolism
  • Pharyngeal Muscles* / metabolism
  • Sleep Apnea, Obstructive*

Substances

  • NRF1 protein, human
  • Nuclear Respiratory Factor 1
  • PPARGC1A protein, human
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha