A new study published today in the journal Science Advances reveals that sleep apnea, a condition affecting nearly one billion people worldwide, disrupts the liver’s biological clock, altering its daily metabolic activity. Researchers at the University Grenoble Alpes, the Inserm (French National Institute of Health and Medical Research), and the Grenoble Alpes University Hospital conducted the research, utilizing a murine model of chronic intermittent hypoxia – the repeated oxygen deprivation characteristic of sleep apnea.
The study focused on the liver, a central organ in energy regulation, and analyzed its metabolic adaptations over a full day-night cycle. Researchers found that intermittent hypoxia alters major energy pathways, including glucose and lipid metabolism. Crucially, the study demonstrates a profound modification of the circadian organization – the body’s natural rhythm aligned with day and night. According to Inserm, the research shows that nearly half of the liver’s metabolic components exhibit a 24-hour rhythm, and over a third acquire a new rhythm under conditions of intermittent hypoxia.
“This redistribution of metabolic rhythms throughout the day translates into a real temporal reprogramming of liver activity and highlights a previously underestimated dimension of sleep apnea,” Inserm stated in a press release.
Sleep apnea, or obstructive sleep apnea-hypopnea syndrome (OSAHS), is characterized by repeated collapses of the upper airways during sleep, leading to interruptions or reductions in breathing. In France, approximately 1.8 million people are currently treated with continuous positive airway pressure (CPAP), the standard treatment for moderate to severe cases. According to the French health insurance authority, ameli.fr, around 4% of the French population is affected by OSAHS.
The findings have implications for the emerging field of chronomedicine, which advocates for tailoring medical treatments to an individual’s circadian rhythms. Researchers suggest that these metabolic reprogrammings could influence how the body responds to certain medications, particularly those affecting blood sugar or lipid metabolism. The study’s authors recommend integrating a temporal dimension into the management of sleep apnea, potentially re-evaluating the optimal timing for medication administration in patients with the condition.
The study’s findings raise questions about the broader impact of sleep apnea on metabolic health and the potential for chronotherapeutic interventions to improve treatment outcomes. Further research is needed to determine the clinical relevance of these findings and to develop personalized treatment strategies based on individual circadian profiles.
