Sleep deprivation reduces neuroglobin immunoreactivity in the rat brain

Abstract

Neuroglobin (Ngb), a protein located in the mammal's brain, is involved in oxygen transport and free radical scavenging inside the neurons. Ngb colocalizes with choline acetyltransferase in the laterodorsal tegmental nucleus and in the pontine tegmental nucleus, both involved in the sleep-wake cycle regulation. Some studies have shown that free radicals accumulated during prolonged wakefulness are removed during sleep. Therefore, Ngb could act as a regulator of free radicals generated during prolonged wakefulness in the brain. The aim of this study was to determine whether prolonged wakefulness affects Ngb immunoreactivity because of increases in the oxidative stress induced by continuous neuronal activity. For this purpose, male adult Wistar rats were implanted with electrodes for sleep recordings and were divided into control and sleep-deprived groups. Sleep deprivation was carried out for 24 h by gentle handling of the animals. Sleep-wake activity was determined during the deprivation period or 24 h of control conditions. Subsequently, both groups of animals were killed and their brains were obtained and processed for Ngb immunohistochemical analysis and detection of lipid peroxidation. Our data found no evidence of increased oxidative stress in the brains of sleep-deprived animals compared with the controls. The number of Ngb-positive cells was decreased in the sleep-deprived animals in all analyzed areas of the brain compared with the control group. Our results suggest that Ngb could be involved in sleep regulation, independent of its role in the control of oxidative stress.

Sleep deprivation induces differential morphological changes in the hippocampus and prefrontal cortex in young and old rats

“…On the other hand, stress seems to negatively affect dendritic morphology (Liston and Gan, ; Radley et al, ); however, in a previous study, we found no changes in serum corticosterone levels, and no signs of stress‐induced damage in cells were observed as a result of our sleep deprivation method (Melgarejo‐Gutierrez et al, ). Recently, findings show that higher levels of corticosterone than observed here are necessary to induce a significant increase in density of dendritic spines (Yoshiya et al, ).…”

“…Briefly, rats were kept awake by gentle touching in their tails, coat, or whiskers, soft shaking of their cages, or handling them to prevent falling asleep. Gentle handling is a common procedure used to perform total sleep deprivation in rodents because it induces minimal stress (Franken et al, 1991;Melgarejo-Gutierrez et al, 2013;Romcy-Pereira and Pavlides, 2004).…”

Sleep deprivation and stress: a reciprocal relationship

“…Despite having been initially designed to minimize the spurious consequences of stress on sleep, the effects of GH on the HPA axis activity is more controversial than the consensually recognized stressful effects of sleep-deprivation protocols based on forced locomotion. The exposure to external stimuli between 2 and 24 h has been shown to induce an increase in corticosterone levels in male mice [100][101][102][103][104][105] and rats [106][107][108][109][110], as well as for very short periods of time in neonatal rats [110]. However, this increase was usually mild and within the range of normal amplitude observed during the undisturbed period.…”

“…It has been shown that mice kept awake with as little disturbance as possible display lower corticosterone levels than animals kept awake using social stimuli or regular direct handling [111,112]. If rats seem to be less affected by stress during GH procedures [109,113], conflicting results have been reported regarding the habituation of mice to GH. Compared with undisturbed animals, 3 min of daily GH during 6 days in male mice induced no alteration in corticosterone release during the first day then an increase in corticosterone by the end of the sixth day [114], while the exact opposite was also described [115].…”

Neuroglobin in Neurons of the Frontal and Parietal Cortex of White Rats in Cholestasis

“…Интересно, что уменьшение количества нейроглобина коррелирует с когнитивной дисфункцией [8]. Кроме того, показана роль нейроглобина в процессах сна и бодрствования [11]. Возможно, наблюдаемые неврологические и психические нарушения в клинике у больных с холестазом связаны именно с этим белком.…”