MPO and obstructive sleep apnea syndrome: Short-term sleep restriction has also been associated with elevated levelsof myeloperoxidase, an enzyme involved in the formation of oxidants.Myeloperoxidase can modify low-density lipoprotein cholesterol into oxidizedlow-density lipoprotein cholesterol, exacerbating endothelial damage and lipidaccumulation, thus promoting the progression of atherosclerosis [99, 100].Nighttime intermittent hypoxia in OSA patients is closely associated withincreased oxidative stress, elevated inflammatory cytokines, imbalance in nitricoxide production, and endothelial injury.