PPARGC1A and obstructive sleep apnea syndrome: The results of this study also found that the expression of NRF‐1 is down‐regulated in palatopharyngeus muscle of patients with OSA, but the relationship between the down‐regulation of NRF‐1 and PGC‐1α expression and the conversion of palatopharyngeus muscle in patients with OSA remains to be further explored.