A new animal study from researchers at Ibn Tofail University in Morocco provides a detailed look at how prolonged REM sleep deprivation damages the body’s ability to regulate blood sugar, pointing to oxidative stress and tissue damage as key mechanisms linking chronic sleep loss to type 2 diabetes. The findings, published July 7 in _Sleep Medicine_, come from experiments in adult male Wistar rats and offer a preclinical window into the biological chain that may connect sleep disruption to metabolic disease in humans.
Researchers led by Wissal Baghdad subjected rats to daily REM sleep deprivation for 18 hours per day over five consecutive weeks, using a method designed to selectively eliminate rapid-eye-movement sleep while minimizing physical stress. After the deprivation period, the animals underwent glucose tolerance tests and insulin tolerance tests, along with panels measuring oxidative stress markers, regulatory hormones, and tissue health in the liver and pancreas.
What they found
Rats that underwent chronic REM sleep deprivation showed a constellation of metabolic disturbances. Key findings include:
- Glucose intolerance. The deprived animals handled blood sugar significantly worse than controls on the glucose tolerance test, indicating impaired glucose clearance.
- Elevated plasma glucose. Fasting blood glucose levels were higher in the REM-deprived group.
- Increased insulin sensitivity. In the insulin tolerance test, deprived rats showed a greater drop in blood glucose in response to insulin, suggesting altered insulin signaling dynamics.
- Elevated stress hormones. Plasma corticosterone, the primary stress hormone in rodents, was significantly higher in the deprivation group.
- Markers of cellular damage. Lactate dehydrogenase (LDH), an enzyme released when cells are damaged, was elevated, consistent with cytotoxicity.
- Oxidative stress. Multiple markers of oxidative stress were increased, indicating that prolonged REM deprivation pushed cells into a state of biochemical imbalance.
- Reduced BuChE activity. Butyrylcholinesterase, an enzyme involved in metabolic regulation and cholinergic signaling, was significantly decreased.
- Liver and pancreas damage. Histopathological examination of the liver and pancreatic tissue revealed structural changes confirming organ impairment.
The researchers used the modified multi-platform method (MMPM), a well-established technique that keeps animals on small platforms surrounded by water. When rats enter REM sleep, their muscle tone drops and they fall into the water, awakening them. This selectively deprives them of REM sleep specifically, rather than causing general sleep disruption.
Why it matters
Poor sleep is increasingly recognized as a risk factor for type 2 diabetes, but the biological mechanisms have been difficult to pin down. Human studies can show correlations between short sleep and impaired glucose metabolism, but they cannot easily dissect the cellular pathways involved, and they cannot ethically induce prolonged selective sleep deprivation.
This study provides some of the most detailed experimental evidence that REM sleep deprivation alone, independent of total sleep time or other confounders, can trigger a cascade that starts with oxidative stress and cytotoxicity in the liver and pancreas, progresses to dysregulated glucose handling, and ultimately creates conditions that resemble early-stage type 2 diabetes.
The findings also highlight the potential role of butyrylcholinesterase (BuChE), an enzyme that has received less attention in the sleep-diabetes literature. Its reduction in deprived animals suggests that cholinergic signaling may be a missing piece of the puzzle linking sleep loss to metabolic decline.
Limits
This is an animal study, and the results may not directly translate to humans. Rats have different sleep architecture and metabolic physiology than people, and the deprivation protocol, 18 hours per day for five weeks, is far more severe than what humans typically experience. The sample size was small (six animals per group), and only male rats were used, so sex-specific effects could not be assessed. The study also did not include a recovery period to determine whether the observed changes are reversible once normal sleep resumes.
Bottom line
In a rodent model, five weeks of daily REM sleep deprivation produced glucose intolerance, elevated blood sugar, oxidative stress, and visible damage to the liver and pancreas. The findings strengthen the case that chronic REM sleep loss contributes to type 2 diabetes through mechanisms involving oxidative stress and cellular injury, and they point to specific biomarkers, including BuChE and corticosterone, that may warrant further investigation in human studies.
Source
Wissal Baghdad, Mohamed Yassine El Brouzi, Aboubaker El Hessni, Sara El Ghaffouli, Otmane El Harrati, Marouane El Arbaoui, Oumaima Abouyaala, Amal Dimaoui, Leila Ibouzine-Dine, Ihsane Hmamouchi, Ouafaa Fassi Fihri, Charifa Drissi Touzani, Amal Satté, Amal Damiri, Abdelhalem Mesfioui. “Impact of chronic REM sleep deprivation on glucose homeostasis, insulin sensitivity, oxidative stress, and histological changes in adult male Wistar rats.” _Sleep Medicine_, vol. 146, 2026, p. 109105. DOI: 10.1016/j.sleep.2026.109105. PMID: 42407329.