Work

Metabolic Effects of Chronic Sleep Restriction in Rats

Year: 2012

Type: article

Abstract: STUDY OBJECTIVES: Chronic partial sleep loss is associated with obesity and metabolic syndrome in humans. We used rats with lesions in the ventrolateral preoptic area (VLPO), which spontaneously sleep about 30% less than intact rats, as an animal model to study the consequences of chronic partial sleep loss on energy metabolism. PARTICIPANTS: Adult male Sprague-Dawley rats (300-365 g). INTERVENTIONS: We ablated the VLPO in rats using orexin-B-saporin and instrumented them with electrodes for sleep recordings. We monitored their food intake and body weight for the next 60 days and assessed their sleep-wake by 24-h EEG/EMG recordings on day 20 and day 50 post-surgery. On day 60, after blood samples were collected for metabolic profiling, the animals were euthanized and the brains were harvested for histological confirmation of the lesion site. MEASUREMENTS AND RESULTS: VLPO-lesioned animals slept up to 40% less than sham-lesioned rats. However, they showed slower weight gain than sham-lesioned controls, despite having normal food intake. An increase in plasma ghrelin and a decrease in leptin levels were observed, whereas plasma insulin levels remained unaffected. As expected from leaner animals, plasma levels of glucose, cholesterol, triglycerides, and C-reactive protein were reduced in VLPO-lesioned animals. CONCLUSIONS: Chronic partial sleep loss did not lead to obesity or metabolic syndrome in rats. This finding raises the question whether adverse metabolic outcomes associated with chronic partial sleep loss in humans may be due to factors other than short sleep, such as circadian disruption, inactivity, or diet during the additional waking hours.

Source: SLEEP

DOI: 10.5665/sleep.2200

Authors: Ramalingam Vetrivelan, Patrick M. Fuller, Shigefumi Yokota, Jun Lu, Clifford B. Saper

Institutions: Beth Israel Deaconess Medical Center, Harvard University

Language: English

Topic: Sleep and Wakefulness Research

Subfield: Cognitive Neuroscience

Field: Neuroscience

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: green