Brain energetics during the sleep–wake cycle

Abstract

Brain activity during wakefulness is associated with high metabolic rates that are believed to support information processing and memory encoding. In spite of loss of consciousness, sleep still carries a substantial energy cost. Experimental evidence supports a cerebral metabolic shift taking place during sleep that suppresses aerobic glycolysis, a hallmark of environment-oriented waking behavior and synaptic plasticity. Recent studies reveal that glial astrocytes respond to the reduction of wake-promoting neuromodulators by regulating volume, composition and glymphatic drainage of interstitial fluid. These events are accompanied by changes in neuronal discharge patterns, astrocyte-neuron interactions, synaptic transactions and underlying metabolic features. Internally-generated neuronal activity and network homeostasis are proposed to account for the high sleep-related energy demand.

Enhanced meningeal lymphatic drainage ameliorates neuroinflammation and hepatic encephalopathy in cirrhotic rats

“…A 66 kDa fluorescent tracer, ovalbumin conjugated with Alexa Flour 647 (OVA-647, Thermo Fisher Scientific, Waltham, MA), was injected into the cisterna magna of rats under anesthesia with ketamine (75 mg/kg) and xylazine (5 mg/kg) to evaluate glymphatic function and meningeal lymphatic drainage. Depth of anesthesia was kept consistent among rats to avoid a differential influence of anesthesia on their glymphatic function 20 . An anesthesia protocol was adapted from a previous study with slight modifications 21 .…”

Digital Transformation of Continuous Education: A New Volution of the Development of Neuropedagogy

“…Однако вспомним тезис о том, что при интенсивном цифровом потоке воспринимаемых и обрабатываемых данных функция глубокой переработки информации является самостоятельным видом мозговой деятельности, отделенной от глубокой переработки и осмысления определенным временным промежутком. Время переработки информации и перенос ее в долговременную память все больше перемещается на время фаз глубокого сна [6]. Здесь нейрофизиологические исследования выявляют новый уровень проблем, связанных с нарушениями циклов сна и, соответственно, с невозможностью для мозга переработать информацию, полученную за день [16][17][18].…”

The molecular genetics of human sleep

“…On the other hand, the mechanism for sleep quality and quantity remains much less understood. Although many theories on sleep functions, such as synaptic regulation, toxin clearance, and energy regeneration, etc., have been proposed, their direct connection to human sleep awaits further validation (DiNuzzo & Nedergaard, ).…”