Time for a good night's sleep
Sleep disorders have haunted man for centuries, significantly undermining well-being, productiveness and quality of life of the sufferers. Yet little is known about the exact mechanisms of sleep disorders and remedies to overcome them have been of limited help. The EU-funded project 'Disorders of sleep regulation: basic mechanisms and thepapeutic perspectives' (Enough SLEEP) developed new diagnostic tools to understand sleep ailments. It looked closely at the mechanisms of sleep regulation from molecular, genetic and electrophysiological perspectives using a novel systems approach to gain ground in revealing exact sleep regulation mechanisms. In the long run, the project aimed to use these diagnostic tools to remedy these disorders, particularly with respect to the persistent and often debilitating ailments of depression and insomnia. In its first stage, the Enough SLEEP project began by identifying cortical and sub-cortical mechanisms of sleep regulation, as well as genetic and humoral mechanisms involved. It examined the role of non-neuronal glial cells (or glia) implicated in sleep regulation and aimed to understand the exact mechanisms that alter sleep regulation. Beyond this, the project accurately studied links between cortical activity, excitability and sleep through high density electroencephalography (EEG) and transcranial magnetic stimulation (TMS). Importantly, the project team clarified the relationship between high sleep pressure and an increased slope of slow waves, enabling researchers to use the slope as an indicator of sleep homeostasis. It also brought to light correlations between memory and sleep in mice. Memory deficit occurred when sleep deprivation immediately followed acquisition during the daytime, the rest time for mice. However, there was no effect when performed during the waking period of mice at night. In addition, Enough Sleep found that the Basal forebrain cholinergic (BF) cells are crucial in recovery sleep, i.e. after long periods of wakefulness. Other key findings have involved intriguing links between sleep and the immune system by measuring regulators of cytokine activity and microglia among other parameters. These findings have helped the project outline new diagnostic approaches to study sleep regulation and which in turn could lead to more effective research and testing. The advent of finding more viable treatments for insomnia and depression is now within reach.
