Literature Updates from May 2013

Occurrence of Rapid Eye Movement Sleep Deprivation After Surgery Under Regional Anesthesia

This study shows that postoperative reduction of REM sleep occurs after surgery with general anesthesia as it does with regional anesthesia.

Advanced Sleep Schedules Affect Circadian Gene Expression in Young Adults with Delayed Sleep Schedules

Twenty-one young adults had their blood drawn 1.5 hours before and 1.5 hours after the estimated time of dim light melatonin onset (DMLO). Participants were randomized to one week of either 1-hour morning blue light exposure or comparable dim light exposure; circadian genes were assessed. Analyses revealed significant changes in gene expression of 10 circadian genes in response to sleep-wake schedule advancement and morning blue-light stimulation.

One Night On-Call: Sleep Deprivation Affects Cardiac Autonomic Control and Inflammation in Physicians

Fifteen healthy residents in Internal Medicine were studied before and after one night on-call (i.e., acute sleep deprivation (ASD)) at rest and during gravitational stimulus. ASD was associated with modulation of sympathovagal balance toward sympathetic activation and increased levels of IFN-gamma compared to baseline. ASD was unrelated to changes in blood pressure variability and baroreflex sensitivity.

Selective Slow Wave Sleep But Not Rapid Eye Movement Sleep Suppression Impairs Morning Glucose Tolerance in Healthy Men

Sixteen healthy men underwent 3 experimental conditions in a cross-over design: SWS suppression, REM-sleep disturbance, and regular sleep; a glucose tolerance test was obtained the following morning. Morning plasma glucose and serum insulin responses were selectively increased and postprandial insulin sensitivity was reduced after SWS suppression. Disturbed REM had no effect on glucose homeostasis.

Sleep Apnea, Sleepiness, Inflammation and Insulin Resistance in Middle-Aged Men and Women

Seventy-seven non-obese (38 men and 39 women) with OSA were studied in the sleep laboratory over 4 nights and serial blood samples were taken. Apneic men were sleepier and had higher levels of hsCRP, IL-6, leptin and insulin resistance than controls; women did not show consistent elevations. Short term CPAP did not improve these markers.

Extrasynaptic GABAA Receptors in Rat Pontine Reticular Formation Increase Wakefulness

This study used gaboxadol (agonist at extrasynaptic GABAA receptors that contain a δ subunit) to test show that extrasynaptic GABAA receptors within the pontine reticular formation modulate sleep and wakefulness.

Hypocretin/Orexin Neurons Contribute to Hippocampus-Dependent Social Memory and Synaptic Plasticity in Mice

Hypocretin/orexin (Hcrt)-producing neurons orchestrate global arousal state, wake-sleep architecture, energy homeostasis, stress adaptation, and reward behaviors. This study demonstrate that Hcrt neurons play an important role in the consolidation of social recognition memory, at least in part through enhancements of hippocampal synaptic plasticity and cAMP response element-binding protein phosphorylation.

Serum, Urine, and Breath-Related Biomarkers in the Diagnosis of Obstructive Sleep Apnea in Children: Is It for Real?

It is likely that the modest efforts thus far realized in the context of biomarker discovery for the diagnosis and clinical monitoring of OSA in children will experience major acceleration in the upcoming years…

Macrophage Migration Inhibitory Factor Gene Polymorphisms and Plasma Levels in Children with Obstructive Sleep Apnea

Childhood OSA is associated with higher plasma MIF, hsCRP, and fasting insulin levels that promote cardiometabolic risk, and the MIF gene SNP rs10433310 may account for some of the variance in such risk.

Craniofacial and Upper Airway Morphology in Pediatric Sleep-Disordered Breathing: Systematic Review and Meta-Analysis

…evidence for a direct causal relationship between craniofacial structure and pediatricsleep-disordered breathing is unsupported by this meta-analysis. There is strong support for reduced upperairway width in children with obstructive sleep apnea.