Effect of oxidative stress induced by paradoxical sleep deprivation on the activities of Na+, K+-ATPase and acetylcholinesterase in the cortex and hippocampus of rat

Acute 2-phenyl-3-(phenylselanyl)benzofuran treatment reverses the neurobehavioral alterations induced by sleep deprivation in mice

Sleep is a fundamental state for maintaining the organism homeostasis. Disruptions in sleep patterns predispose to the appearance of memory impairments and mental disorders, including depression. Recent pre-clinical studies have highlighted the antidepressant-like properties of the synthetic compound 2-phenyl-3-(phenylselanyl)benzofuran (SeBZF1). To further investigate the neuromodulatory effects of SeBZF1, this study aimed to assess its therapeutic efficacy in ameliorating neurobehavioral impairments induced by sleep deprivation (SD) in mice. For this purpose, a method known as multiple platforms over water was used to induce rapid eye movement (REM) SD. Two hours after acute SD (24 h), male Swiss mice received a single treatment of SeBZF1 (5 mg/kg, intragastric route) or fluoxetine (a positive control, 20 mg/kg, intraperitoneal route). Subsequently, behavioral tests were conducted to assess spontaneous motor function (open-field test), depressive-like behavior (tail suspension test), and memory deficits (Y-maze test). Brain structures were utilized to evaluate oxidative stress markers, monoamine oxidase (MAO) and acetylcholinesterase (AChE) activities. Our findings revealed that SD animals displayed depressive-like behavior and memory impairments, which were reverted by SeBZF1 and fluoxetine treatments. SeBZF1 also reverted the increase in lipoperoxidation levels and glutathione peroxidase activity in the pre-frontal cortex in mice exposed to SD. Besides, the increase in hippocampal AChE activity induced by SD was overturned by SeBZF1. Lastly, cortical MAO-B activity was reestablished by SeBZF1 in mice that underwent SD. Based on the main findings of this study, it can be inferred that the compound SeBZF1 reverses the neurobehavioral alterations induced by sleep deprivation in male Swiss mice.

Transcranial Irradiation Mitigates Paradoxical Sleep Deprivation Effect in an Age-Dependent Manner: Role of BDNF and GLP-1

The growing prevalence of aged sleep-deprived nations is turning into a pandemic state. Acute sleep deprivation (SD) accompanies aging, changing the hippocampal cellular pattern, neurogenesis pathway expression, and aggravating cognitive deterioration. The present study investigated the ability of Near Infra Red (NIR) light laser to ameliorate cognitive impairment induced by SD in young and senile rats. Wistar rats ≤ 2 months (young) and ≥ 14 months (senile) were sleep-deprived for 72 h with or without transcranial administration of NIR laser of 830 nm. Our results showed that NIR photobiomodulation (PBM) attenuated cognitive deterioration made by SD in young, but not senile rats, while both sleep-deprived young and senile rats exhibited decreased anxiety (mania)-like behavior in response to PBM. NIR PBM had an inhibitory effect on AChE, enhanced the production of ACh, attenuated ROS, and regulated cell apoptosis factors such as Bax and Bcl-2. NIR increased mRNA expression of BDNF and GLP-1 in senile rats, thus facilitating neuronal survival and differentiation. The present findings also revealed that age exerts an additive factor to the cellular assaults produced by SD where hippocampal damages made in 2-month rats were less severe than those of the aged one. In conclusion, NIR PBM seems to promote cellular longevity of senile hippocampal cells by combating ROS, elevating neurotrophic factors, thus improving cognitive performance. The present findings provide NIR as a possible candidate for hippocampal neuronal insults accompanying aging and SD.

Biological rhythms are correlated with Na+, K+-ATPase and oxidative stress biomarkers: A translational study on bipolar disorder

BACKGROUND

Bipolar disorder (BD) is a chronic, severe, and multifactorial psychiatric disorder. Although biological rhythms alterations, sodium potassium pump (Na+, K+-ATPase) changes, and oxidative stress appear to play a critical role in the etiology and pathophysiology of BD, the inter-connection between them has not been described. Therefore this study evaluated the association between biological rhythms, Na+, K+-ATPase, and oxidative stress parameters in BD patients and the preclinical paradoxical sleep deprivation model (PSD).

METHODS

A translational study was conducted, including a case-control protocol with 36 BD and 46 healthy controls (HC). Subjects completed the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN). In addition, Erythrocyte Na+, K+-ATPase activity, and oxidative and nitrosative stress markers were assessed (4-hydroxynonenal [4-HNE], 8-isoprostane [8-ISO], thiobarbituric acid reactive substances [TBARS], carbonyl, 3-nitrotyrosine [3-nitro]). In the preclinical protocol, the same biomarkers were evaluated in the frontal cortex, hippocampus, and striatum from mice submitted to the PSD.

RESULTS

BD patients had a significantly higher total score of BRIAN versus HCs. Additionally, individuals with BD showed decreased Na+, K+-ATPase activity and increased oxidative stress parameters compared to HC without psychiatric disorders. This difference was driven by actively depressed BD subjects. The mice submitted to the PSD also demonstrated decreased Na+, K+-ATPase activity and increased oxidative stress parameters.

LIMITATIONS

BRIAN biological underpinning is less well characterized; We did not control for medication status; Sample size is limited; PSD it is not a true model of BD.

CONCLUSIONS

The present study found a significant correlation between Na+, K+-ATPase and oxidative stress with changes in biological rhythms, reinforcing the importance of these parameters to BD.

The simultaneous action of acute paradoxical sleep deprivation and hypothyroidism modulates synaptosomal ATPases and acetylcholinesterase activities in rat brain

BACKGROUND

Thyroid dysfunctions as well as sleep abnormalities are usually followed by neurological, psychiatric and/or behavioral disorders. On the other hand, changes in the brain adenosine triphosphatases (ATPases) and acetylcholinesterase (AChE) activities show significant importance in pathogenetic pathways in the evolution of numerous neuropsychiatric diseases.

METHODS

This study aimed to evaluate the in vivo simultaneous effects of hypothyroidism and paradoxical sleep deprivation for 72 h on synaptosomalATPases and AChE activities of whole rat brains. In order to induce hypothyroidism, 6-n-propyl-2-thiouracil was administrated in drinking water during 21 days. The modified multiple platform method was used to induce paradoxical sleep deprivation. The AChE and ATPases activities were measured using spectrophotometric methods.

RESULTS

Hypothyroidism significantly increased the activity of Na⁺/K⁺-ATPase compared to other groups, while at the same time significantly decreased AChE activity compared to the CT and SD groups. Paradoxical sleep deprivation significantly increased AChE activity compared to other groups. The simultaneous effect of hypothyroidism and sleep deprivation reduced the activity of all three enzymes (for Na⁺/K⁺-ATPase between HT/SD and HT group p < 0.0001, SD group p < 0.001,CT group p = 0.013; for ecto-ATPases between HT/SD and HT group p = 0.0034, SD group p = 0.0001, CT group p = 0.0007; for AChE between HT/SD and HT group p < 0.05, SD group p < 0.0001, CT group p < 0.0001).

CONCLUSIONS

The effect of simultaneous existence of hypothyroidism and paradoxical sleep deprivation reduces the activity of the Na⁺/K⁺-ATPase, ecto-ATPases, and AChE, what is different from individual effect of hypothyroidism and paradoxical sleep deprivation itself. This knowledge could help in the choice of appropriate therapy in such condition.

Therapeutic effects of growth hormone in a rat model of total sleep deprivation: Evaluating behavioral, hormonal, biochemical and electrophysiological parameters

OBJECTIVE

Total sleep deprivation (TSD) causes several harmful changes in the brain, including memory impairment, increased stress and depression levels, as well as reduced antioxidant activity. Growth hormone (GH) has been shown to boost antioxidant levels while improving memory and depression. The present study was conducted to explain the possible effects of exogenous GH against behavioral and biochemical disorders caused by TSD and the possible mechanisms involved.

MAIN METHODS

To induce TSD, rats were housed in homemade special cages equipped with stainless steel wire conductors to induce general and inconsistent TSD. They received a mild repetitive electric shock to their paws every 10 min for 21 days. GH (1 ml/kg, sc) was administered to rats during induction of TSD for 21 days. Memory retrieval, anxiety, depression-like behaviors, pain behaviors, antioxidant activity, hippocampal level of BDNF, and simultaneously brain electrical activity were measured at scheduled times after TSD.

KEY FINDINGS

The results showed that GH treatment improved memory (p < 0.001) in the PAT test of rats exposed to TSD. These beneficial effects were associated with lowering the level of anxiety and depression-like behavior (p < 0.001), rising the pain threshold (p < 0.01), increasing the activity of antioxidants (p < 0.01), hippocampal BDNF (p < 0.001), and regular brain electrical activity.

SIGNIFICANCE

Our findings show that GH plays a key role in modulating memory, anxiety and depression behaviors, as well as reducing oxidative stress and improve hippocampal single-unit activity in the brain during TSD.

Consequences of post-weaning sleep deprivation on behaviour and oxidative stress parameters in rat plasma and brain

Sleep is essential for health: Adequate sleep is essential for healthy development and sleep deprivation results in several consequences. Indeed, sleep deprivation early in life is associated with poor behaviour and cognition, as well as impaired mental and physical health. Preclinical studies have shown that sleep deprivation alters several physiological functions later in life such as the cardiovascular, immune and endocrine systems, resulting in altered oxidative states. Most of the preclinical literature is focused on adult animals, and little is known about oxidative alterations during development, especially in the context of sleep deprivation. Hence, we adapted a classic and well-documented model of sleep deprivation, paradoxical sleep deprivation using multiple platforms, for juvenile rats and explored central and peripheral oxidative parameters, as well as the behavioural consequences of sleep deprivation post-weaning. We showed that 96 h of paradoxical sleep deprivation induced a significant reduction in body weight, decreased sucrose preference-a behaviour suggestive of anhedonia-and increased glucose and decreased cholesterol in the plasma. In the brain, we observed a decrease in reduced glutathione levels in the medial prefrontal cortex and an increase in thiobarbituric acid reactive substance levels in the hypothalamus, indicating oxidative damage in these regions. Taken together, our findings suggest that paradoxical sleep deprivation during development induces anhedonic behaviour and promotes central and peripheral alterations in oxidative parameters.

Neural consequences of chronic sleep disruption

Recent studies in both humans and animal models call into question the completeness of recovery after chronic sleep disruption. Studies in humans have identified cognitive domains particularly vulnerable to delayed or incomplete recovery after chronic sleep disruption, including sustained vigilance and episodic memory. These findings, in turn, provide a focus for animal model studies to critically test the lasting impact of sleep loss on the brain. Here, we summarize the human response to sleep disruption and then discuss recent findings in animal models examining recovery responses in circuits pertinent to vigilance and memory. We then propose pathways of injury common to various forms of sleep disruption and consider the implications of this injury in aging and in neurodegenerative disorders.

Sericin protects against acute sleep deprivation-induced memory impairment via enhancement of hippocampal synaptic protein levels and inhibition of oxidative stress and neuroinflammation in mice

Sleep deprivation (SD) induces learning and memory deficits via inflammatory responses and oxidative stress. On the other hand, sericin (Ser) possesses potent antioxidant and neuroprotective effects. We investigated the effect of different doses of Ser on the SD-induced cognitive impairment. Ser (100, 200, and 300 mg/kg) was administered to animals via oral gavage for 8 days, 5 days before to SD, and during SD. SD was induced in mice using a modified multiple platform model, starting on the 6th day for 72 h. Spatial learning and memory were assessed using the Lashley III maze. Serum corticosterone level, and hippocampal malondialdehyde (MDA), total antioxidant capacity (TAC), and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes were evaluated. The expression of growth-associated protein 43 (GAP-43), post-synaptic density-95 (PSD-95), synapsin 1 (SYN-1), and synaptophysin (SYP), and inflammation markers were detected by western blotting. SD caused cognitive impairment, while Ser pretreatment prevented such an effect. Serum corticosterone also increased with SD, but its levels were suppressed in SD mice receiving Ser. Furthermore, Ser normalized SD-induced reduction in the hippocampus activity of SOD and GPx, increased TAC, and decreased MDA levels. Besides, Ser pretreatment increased GAP-34, SYP, SYN-I, and PSD-95 and reduced IL1-β and TNF-α in the hippocampus. SD induced memory impairment and pretreatment with Ser improved memory via its antioxidant, anti-inflammation, and up-regulation of synaptic proteins in the hippocampus.

Impact of REM sleep deprivation and sleep recovery on circulatory neuroinflammatory markers

Objectives

Sleep loss may contribute to neuroinflammation, which might increase neuroinflammatory markers such as neuron-specific enolase (NSE), creatine kinase-brain fraction (CK-BB), lactate dehydrogenase brain fraction (LDH-BB) in blood. Hence, we evaluated the effect of REM sleep deprivation and recovery on these markers.

Material and Methods

Twenty-four adult male Sprague Dawley rats were grouped as control, environmental control, REM sleep deprivation, and 24 hour sleep recovery. The rats were sleep deprived for 72 hours and recovered for 24 hours. NSE, CK-BB, and LDH-BB levels in serum were measured using ELISA.

Results

The serum NSE, CK-BB, and LDH-BB were significantly higher in 72 hour sleep deprived group compared to control (p<0.01). After 24 hours of sleep recovery, the levels of NSE, CK-BB, and LDH-BB were comparable to control (p>0.05).

Discussion

REM sleep deprivation increased serum NSE, CK-BB, and LDH-BB, which might be due to neural damage. However, 24 hours of sleep recovery restored these markers.

Topological reorganizations of mitochondria isolated from rat brain after 72 hours of paradoxical sleep deprivation, revealed by electron cryo-tomography

Sleep deprivation has profound influence on several aspects of health and disease. Mitochondria dysfunction has been implicated to play an essential role in the neuronal cellular damage induced by sleep deprivation, but little is known about how neuronal mitochondrial ultrastructure is affected under sleep deprivation. In this report, we utilized electron cryo-tomography to reconstruct the three-dimensional (3-D) mitochondrial structure and extracted morphometric parameters to quantitatively characterize its reorganizations. Isolated mitochondria from the hippocampus and cerebral cortex of adult male Sprague-Dawley rats after 72 h of paradoxical sleep deprivation (PSD) were reconstructed and analyzed. Statistical analysis of six morphometric parameters specific to the mitochondrial inner membrane topology revealed identical pattern of changes in both the hippocampus and cerebral cortex but with higher significance levels in the hippocampus. The structural differences were indistinguishable by conventional phenotypic methods based on two-dimensional electron microscopy images or 3-D electron tomography reconstructions. Furthermore, to correlate structure alterations with mitochondrial functions, high-resolution respirometry was employed to investigate the effects of PSD on mitochondrial respiration, which showed that PSD significantly suppressed the mitochondrial respiratory capacity of the hippocampus, whereas the isolated mitochondria from the cerebral cortex were less affected. These results demonstrate the capability of the morphometric parameters for quantifying complex structural reorganizations and suggest a correlation between PSD and inner membrane architecture/respiratory functions of the brain mitochondria with variable effects in different brain regions.

Na+/K+-ATPase and lipid peroxidation in forebrain cortex and hippocampus of sleep-deprived rats treated with therapeutic lithium concentration for different periods of time

Lithium (Li) is a typical mood stabilizer and the first choice for treatment of bipolar disorder (BD). Despite an extensive clinical use of Li, its mechanisms of action remain widely different and debated. In this work, we studied the time-course of the therapeutic Li effects on ouabain-sensitive Na⁺/K⁺-ATPase in forebrain cortex and hippocampus of rats exposed to 3-day sleep deprivation (SD). We also monitored lipid peroxidation as malondialdehyde (MDA) production. In samples of plasma collected from all experimental groups of animals, Li concentrations were followed by ICP-MS. The acute (1 day), short-term (7 days) and chronic (28 days) treatment of rats with Li resulted in large decrease of Na⁺/K⁺-ATPase activity in both brain parts. At the same time, SD of control, Li-untreated rats increased Na⁺/K⁺-ATPase along with increased production of MDA. The SD-induced increase of Na⁺/K⁺-ATPase and MDA was attenuated in Li-treated rats. While SD results in a positive change of Na⁺/K⁺-ATPase, the inhibitory effect of Li treatment may be interpreted as a pharmacological mechanism causing a normalization of the stress-induced shift and return the Na⁺/K⁺-ATPase back to control level. We conclude that SD alone up-regulates Na⁺/K⁺-ATPase together with increased peroxidative damage of lipids. Chronic treatment of rats with Li before SD, protects the brain tissue against this type of damage and decreases Na⁺/K⁺-ATPase level back to control level.

Absence of a synergic nigral proapoptotic effect triggered by REM sleep deprivation in the rotenone model of Parkinson´s disease

Excitotoxicity has been related to play a crucial role in Parkinson's disease (PD) pathogenesis. Pedunculopontine tegmental nucleus (PPT) represents one of the major sources of glutamatergic afferences to nigrostriatal pathway and putative reciprocal connectivity between these structures may exert a potential influence on rapid eye movement (REM) sleep control. Also, PPT could be overactive in PD, it seems that dopaminergic neurons are under abnormally high levels of glutamate and consequently might be more vulnerable to neurodegeneration. We decided to investigate the neuroprotective effect of riluzole administration, a N-methyl-D-aspartate (NMDA) receptor antagonist, in rats submitted simultaneously to nigrostrial rotenone and 24h of REM sleep deprivation (REMSD). Our findings showed that blocking NMDA glutamatergic receptors in the SNpc, after REMSD challenge, protected the dopaminergic neurons from rotenone lesion. Concerning rotenone-induced hypolocomotion, riluzole reversed this impairment in the control groups. Also, REMSD prevented the occurrence of rotenone-induced motor impairment as a result of dopaminergic supersensitivity. In addition, higher Fluoro Jade C (FJC) staining within the SNpc was associated with decreased cognitive performance observed in rotenone groups. Such effect was counteracted by riluzole suggesting the occurrence of an antiapoptotic effect. Moreover, riluzole did not rescue cognitive impairment impinged by rotenone, REMSD or their combination. These data indicated that reductions of excitotoxicity, by riluzole, partially protected dopamine neurons from neuronal death and appeared to be effective in relieve specific rotenone-induce motor disabilities.

The role of sleep deprivation and circadian rhythm disruption as risk factors of Alzheimer's disease

Emerging evidence suggests that sleep deprivation (SD) and circadian rhythm disruption (CRD) may interact and increase the risk for the development of Alzheimer's disease (AD). This review inspects different pathophysiological aspects of SD and CRD, and shows that the two may impair the glymphatic-vascular-lymphatic clearance of brain macromolecules (e.g., β-amyloid and microtubule associated protein tau), increase local brain oxidative stress and diminish circulatory melatonin levels. Lastly, this review looks into the potential association between sleep and circadian rhythm with stress granule formation, which might be a new mechanism along the AD pathogenic pathway. In summary, SD and CRD is likely to be associated with a positive risk in developing Alzheimer's disease in humans.

Noradrenaline Acting on Alpha1 Adrenoceptor as well as by Chelating Iron Reduces Oxidative Burden on the Brain: Implications With Rapid Eye Movement Sleep

The noradrenaline (NA) level in the brain is reduced during rapid eye movement sleep (REMS). However, upon REMS deprivation (REMSD) its level is elevated, which induces apoptosis and the degeneration of neurons in the brain. In contrast, isolated studies have reported that NA possesses an anti-oxidant property, while REMSD reduces lipid peroxidation (LP) and reactive oxygen species (ROS). We argued that an optimum level of NA is likely to play a physiologically beneficial role. To resolve the contradiction and for a better understanding of the role of NA in the brain, we estimated LP and ROS levels in synaptosomes prepared from the brains of control and REMS deprived rats with or without in vivo treatment with either α1-adrenoceptor (AR) antagonist, prazosin (PRZ) or α2-AR agonist, clonidine (CLN). REMSD significantly reduced LP and ROS in synaptosomes; while the effect on LP was ameliorated by both PRZ and CLN; ROS was prevented by CLN only. Thereafter, we evaluated in vitro the effects of NA, vitamin E (Vit E), vitamin C (Vit C), and desferrioxamine (DFX, iron chelator) in modulating hydrogen peroxide (H₂O₂)-induced LP and ROS in rat brain synaptosomes, Neuro2a, and C6 cells. We observed that NA prevented ROS generation by chelating iron (inhibiting a Fenton reaction). Also, interestingly, a lower dose of NA protected the neurons and glia, while a higher dose damaged the neurons and glia. These in vitro and in vivo results are complementary and support our contention. Based on the findings, we propose that REMS maintains an optimum level of NA in the brain (an antioxidant compromised organ) to protect the latter from continuous oxidative onslaught.

High Exploratory Phenotype Rats Exposed to Environmental Stressors Present Memory Deficits Accompanied by Immune-Inflammatory/Oxidative Alterations: Relevance to the Relationship Between Temperament and Mood Disorders

Low-exploratory (LE) and high-exploratory (HE) rodents mimic human depressive and hyperthymic temperaments, respectively. Mood disorders (MD) may be developed by the exposure of these temperaments to environmental stress (ES). Psychiatric symptoms severity in MD patients is related to the magnitude of memory impairment. Thus, we aimed at studying the consequences of the exposure of LE and HE male Wistar rats, during periadolescence, to a combination of ES, namely, paradoxical sleep deprivation (PSD) and unpredictable stress (US), on anxiety-related behavior in the plus maze test, working (WM) and declarative memory (DM) performance. We also evaluated hippocampal immune-inflammatory/oxidative, as consequences of ES, and prevention of ES-induced alterations by the mood-stabilizing drugs, lithium and valproate. Medium exploratory (ME) control rats were used for comparisons with HE- and LE-control rats. We observed that HE-controls presented increased anxiolytic behavior that was significantly increased by ES exposure, whereas LE-controls presented increased anxiety-like behavior relative to ME-controls. Lithium and valproate prevented anxiolytic alterations in HE+ES rats. HE+ES- and LE+ES-rats presented WM and DM deficits. Valproate and lithium prevented WM deficits in LE-PSD+US rats. Lithium prevented DM impairment in HE+ES-rats. Hippocampal levels of reduced glutathione (GSH) increased four-fold in HE+ES-rats, being prevented by valproate and lithium. All groups of LE+ES-rats presented increased levels of GSH in relation to controls. Increments in lipid peroxidation in LE+ES- and HE+ES-rats were prevented by valproate in HE+ES-rats and by both drugs in LE+ES-rats. Nitrite levels were increased in HE+ES- and LE+ES-rats (five-fold increase), which was prevented by both drugs in LE+ES-rats. HE+ES-rats presented a two-fold increase in the inducible nitric oxide synthase (iNOS) expression that was prevented by lithium. HE+ES-rats showed increased hippocampal and plasma levels of interleukin (IL)-1β and IL-4. Indoleamine 2, 3-dioxygenase 1 (IDO1) was increased in HE+ES- and LE+ES-rats, while tryptophan 2,3-dioxygenase (TDO2) was increased only in HE+ES-rats. Altogether, our results showed that LE- and HE-rats exposed to ES present distinct anxiety-related behavior and similar memory deficits. Furthermore, HE+ES-rats presented more brain and plasma inflammatory alterations that were partially prevented by the mood-stabilizing drugs. These alterations in HE+ES-rats may possibly be related to the development of mood symptoms.

Transcranial near-infrared photobiomodulation attenuates memory impairment and hippocampal oxidative stress in sleep-deprived mice

Sleep deprivation (SD) causes oxidative stress in the hippocampus and subsequent memory impairment. In this study, the effect of near-infrared (NIR) photobiomodulation (PBM) on learning and memory impairment induced by acute SD was investigated. The mice were subjected to an acute SD protocol for 72 h. Simultaneously, NIR PBM using a laser at 810 nm was delivered (once a day for 3 days) transcranially to the head to affect the entire brain of mice. The Barnes maze and the What-Where-Which task were used to assess spatial and episodic-like memories. The hippocampal levels of antioxidant enzymes and oxidative stress biomarkers were evaluated. The results showed that NIR PBM prevented cognitive impairment induced by SD. Moreover, NIR PBM therapy enhanced the antioxidant status and increased mitochondrial activity in the hippocampus of SD mice. Our findings revealed that hippocampus-related mitochondrial damage and extensive oxidative stress contribute to the occurrence of memory impairment. In contrast, NIR PBM reduced hippocampal oxidative damage, supporting the ability of 810 nm laser light to improve the antioxidant defense system and maintain mitochondrial survival. This confirms that non-invasive transcranial NIR PBM therapy ameliorates hippocampal dysfunction, which is reflected in enhanced memory function.

Exploring the Effect of Ginsenoside Rh1 in a Sleep Deprivation-Induced Mouse Memory Impairment Model

Panax ginseng C.A. Meyer (Araliaceae) has been used in traditional Chinese medicine for enhancing cognition for thousands of years. Ginsenoside Rh1, a constituent of ginseng root, as with other constituents, has memory-improving effects in normal mice and scopolamine-induced amnesic mice. Sleep deprivation (SD) is associated with memory impairment through induction of oxidative stress. The present study investigated the effect of Rh1 against SD-induced cognitive impairment and attempted to define the possible mechanisms involved. Ginsenoside Rh1 (20 μmol/kg; 40 μmol/kg) and modafinil (0.42 g/kg) were administered to the mice intraperitoneally for 23 days. After 14-day SD, locomotor activity was examined using the open field test, and the object location recognition and Morris water maze tests were used to evaluate cognitive ability. The cortex and hippocampus were then dissected and homogenized, and levels and activities of antioxidant defense biomarkers were evaluated to determine the level of oxidative stress. The results revealed that Rh1 prevented cognitive impairment induced by SD, and its ability to reduce oxidative stress in cortex and hippocampus may contribute to the mechanism of action. Copyright © 2017 John Wiley & Sons, Ltd.

Alkaloid extracts from Jimson weed (Datura stramonium L.) modulate purinergic enzymes in rat brain

Although some findings have reported the medicinal properties of Jimson weed (Datura stramonium L.), there exist some serious neurological effects such as hallucination, loss of memory and anxiety, which has been reported in folklore. Consequently, the modulatory effect of alkaloid extracts from leaf and fruit of Jimson weed on critical enzymes of the purinergic [ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5'-nucleotidase (E-NTDase), alkaline phosphatase (ALP) and Na⁺/K⁺ ATPase] system of neurotransmission was the focus of this study. Alkaloid extracts were prepared by solvent extraction method and their interaction with the activities of these enzymes were assessed (in vitro) in rat brain tissue homogenate and in vivo in rats administered 100 and 200mg/kg body weight (p.o) of the extracts for thirty days, while administration of single dose (1mg/kg body weight; i.p.) of scopolamine served as the positive control. The extracts were also investigated for their Fe²⁺ and Cu²⁺ chelating abilities and GC-MS characterization of the extracts was also carried out. The results revealed that the extracts inhibited activates of E-NTPDase, E-NTDase and ALP in a concentration dependent manner, while stimulating the activity of Na⁺/K⁺ ATPase (in vitro). Both extracts also exhibited Fe²⁺ and Cu²⁺ chelating abilities. Considering the EC₅₀ values, the fruit extract had significantly higher (P<0.05) modulatory effect on the enzymes' activity as well as metal chelating abilities, compared to the leaf extract; however, there was no significant difference (P>0.05) in both extracts' inhibitory effects on E-NTDase. The in vivo study revealed reduction in the activities of ENTPDase, E-NTDase, and Na⁺/K⁺ ATPase in the extract-administered rat groups compared to the control group, while an elevation in ALP activity was observed in the extract-administered rat groups compared to the control group. GC-MS characterization revealed the presence of atropine, scopolamine, amphetamine, 3-methyoxyamphetamine, 3-ethoxyamhetamine cathine, spermine, phenlyephirine and 3-piperidinemethanol, among others in the extracts. Hence, alterations of activities of critical enzymes of purinergic signaling (in vitro and in vivo) by alkaloid extracts from leaf and fruit of Jimson weed suggest one of the mechanisms behind its neurological effects as reported in folklore.

Comprehensive Application of Time-of-flight Secondary Ion Mass Spectrometry (TOF-SIMS) for Ionic Imaging and Bio-energetic Analysis of Club Drug-induced Cognitive Deficiency

Excessive exposure to club drug (GHB) would cause cognitive dysfunction in which impaired hippocampal Ca²⁺-mediated neuroplasticity may correlate with this deficiency. However, the potential changes of in vivo Ca²⁺ together with molecular machinery engaged in GHB-induced cognitive dysfunction has never been reported. This study aims to determine these changes in bio-energetic level through ionic imaging, spectrometric, biochemical, morphological, as well as behavioral approaches. Adolescent rats subjected to GHB were processed for TOF-SIMS, immunohistochemistry, biochemical assay, together with Morris water maze to detect the ionic, molecular, neurochemical, and behavioral changes of GHB-induced cognitive dysfunction, respectively. Extent of oxidative stress and bio-energetics were assessed by levels of lipid peroxidation, Na⁺/K⁺ ATPase, cytochrome oxidase, and [¹⁴C]-2-deoxyglucose activity. Results indicated that in GHB intoxicated rats, decreased Ca²⁺ imaging and reduced NMDAR1, nNOS, and p-CREB reactivities were detected in hippocampus. Depressed Ca²⁺-mediated signaling corresponded well with intense oxidative stress, diminished Na⁺/K⁺ ATPase, reduced COX, and decreased 2-DG activity, which all contributes to the development of cognitive deficiency. As impaired Ca²⁺-mediated signaling and oxidative stress significantly contribute to GHB-induced cognitive dysfunction, delivering agent(s) that improves hippocampal bio-energetics may thus serve as a promising strategy to counteract the club drug-induced cognitive dysfunction emerging in our society nowadays.

Effects of Mood Stabilizers on Brain Energy Metabolism in Mice Submitted to an Animal Model of Mania Induced by Paradoxical Sleep Deprivation

There is a body of evidence suggesting that mitochondrial dysfunction is involved in bipolar disorder (BD) pathogenesis. Studies suggest that abnormalities in circadian cycles are involved in the pathophysiology of affective disorders; paradoxical sleep deprivation (PSD) induces hyperlocomotion in mice. Thus, the present study aims to investigate the effects of lithium (Li) and valproate (VPA) in an animal model of mania induced by PSD for 96 h. PSD increased exploratory activity, and mood stabilizers prevented PSD-induced behavioral effects. PSD also induced a significant decrease in the activity of complex II-III in hippocampus and striatum; complex IV activity was decreased in prefrontal cortex, cerebellum, hippocampus, striatum and cerebral cortex. Additionally, VPA administration was able to prevent PSD-induced inhibition of complex II-III and IV activities in prefrontal cortex, cerebellum, hippocampus, striatum and cerebral cortex, whereas Li administration prevented PSD-induced inhibition only in prefrontal cortex and hippocampus. Regarding the enzymes of Krebs cycle, only citrate synthase activity was increased by PSD in prefrontal cortex. We also found a similar effect in creatine kinase, an important enzyme that acts in the buffering of ATP levels in brain; its activity was increased in prefrontal cortex, hippocampus and cerebral cortex. These results are consistent with the connection of mitochondrial dysfunction and hyperactivity in BD and suggest that the present model fulfills adequate face, construct and predictive validity as an animal model of mania.

Sleep deprivation and oxidative stress in animal models: a systematic review

Because the function and mechanisms of sleep are partially clear, here we applied a meta-analysis to address the issue whether sleep function includes antioxidative properties in mice and rats. Given the expansion of the knowledge in the sleep field, it is indeed ambitious to describe all mammals, or other animals, in which sleep shows an antioxidant function. However, in this paper we reviewed the current understanding from basic studies in two species to drive the hypothesis that sleep is a dynamic-resting state with antioxidative properties. We performed a systematic review of articles cited in Medline, Scopus, and Web of Science until March 2015 using the following search terms: Sleep or sleep deprivation and oxidative stress, lipid peroxidation, glutathione, nitric oxide, catalase or superoxide dismutase. We found a total of 266 studies. After inclusion and exclusion criteria, 44 articles were included, which are presented and discussed in this study. The complex relationship between sleep duration and oxidative stress is discussed. Further studies should consider molecular and genetic approaches to determine whether disrupted sleep promotes oxidative stress.

Extended wakefulness: compromised metabolics in and degeneration of locus ceruleus neurons

Modern society enables a shortening of sleep times, yet long-term consequences of extended wakefulness on the brain are largely unknown. Essential for optimal alertness, locus ceruleus neurons (LCns) are metabolically active neurons that fire at increased rates across sustained wakefulness. We hypothesized that wakefulness is a metabolic stressor to LCns and that, with extended wakefulness, adaptive mitochondrial metabolic responses fail and injury ensues. The nicotinamide adenine dinucleotide-dependent deacetylase sirtuin type 3 (SirT3) coordinates mitochondrial energy production and redox homeostasis. We find that brief wakefulness upregulates SirT3 and antioxidants in LCns, protecting metabolic homeostasis. Strikingly, mice lacking SirT3 lose the adaptive antioxidant response and incur oxidative injury in LCns across brief wakefulness. When wakefulness is extended for longer durations in wild-type mice, SirT3 protein declines in LCns, while oxidative stress and acetylation of mitochondrial proteins, including electron transport chain complex I proteins, increase. In parallel with metabolic dyshomeostasis, apoptosis is activated and LCns are lost. This work identifies mitochondrial stress in LCns upon wakefulness, highlights an essential role for SirT3 activation in maintaining metabolic homeostasis in LCns across wakefulness, and demonstrates that extended wakefulness results in reduced SirT3 activity and, ultimately, degeneration of LCns.

Total sleep deprivation alters endothelial function in rats: a nonsympathetic mechanism

STUDY OBJECTIVES

Sleep loss is suspected to induce endothelial dysfunction, a key factor in cardiovascular risk. We examined whether sympathetic activity is involved in the endothelial dysfunction caused by total sleep deprivation (TSD).

DESIGN

TWO GROUPS: TSD (24-h wakefulness), using slowly rotating wheels, and wheel control (WC).

PARTICIPANTS

Seven-month-old male Wistar rats.

INTERVENTIONS

Pharmacological sympathectomy (reserpine, 5 mg/kg, intraperitoneal), nitric oxide synthase (NOS) inhibition (N (G)-nitro-L-arginine, 20 mg/kg, intraperitoneally 30 min before experiment) and cyclooxygenase (COX) inhibition (indomethacin, 5 mg/kg, intraperitoneally 30 min before experiment).

MEASUREMENTS AND RESULTS

In protocol 1, changes in heart rate (HR) and blood pressure were continuously recorded in the sympathectomized and non-sympathectomized rats. Blood pressure and HR increased during TSD in non-sympathectomized rats. In protocol 2, changes in skin blood flow (vasodilation) were assessed in the sympathectomized and non-sympathectomized rats using laser-Doppler flowmetry coupled with iontophoretic delivery of acetylcholine (ACh), sodium nitroprusside (SNP), and anodal and cathodal currents. ACh- and cathodal current-induced vasodilations were significantly attenuated after TSD in non-sympathectomized and sympathectomized rats (51% and 60%, respectively). In protocol 3, ACh-induced vasodilation was attenuated after NOS and COX inhibition (66% and 49%, respectively). Cathodal current-induced vasodilation decreased by 40% after COX inhibition. In TSD compared to WC a decrease in ACh-induced vasodilation was still observed after COX inhibition. No changes in SNP- and anodal current-induced vasodilation were detected.

CONCLUSION

These results demonstrate that total sleep deprivation induces a reduction in endothelial-dependent vasodilation. This endothelial dysfunction is independent of blood pressure and sympathetic activity but associated with nitric oxide synthase and cyclooxygenase pathway alterations.

Sleep, plasticity and the pathophysiology of neurodevelopmental disorders: the potential roles of protein synthesis and other cellular processes

Sleep is important for neural plasticity, and plasticity underlies sleep-dependent memory consolidation. It is widely appreciated that protein synthesis plays an essential role in neural plasticity. Studies of sleep-dependent memory and sleep-dependent plasticity have begun to examine alterations in these functions in populations with neurological and psychiatric disorders. Such an approach acknowledges that disordered sleep may have functional consequences during wakefulness. Although neurodevelopmental disorders are not considered to be sleep disorders per se, recent data has revealed that sleep abnormalities are among the most prevalent and common symptoms and may contribute to the progression of these disorders. The main goal of this review is to highlight the role of disordered sleep in the pathology of neurodevelopmental disorders and to examine some potential mechanisms by which sleep-dependent plasticity may be altered. We will also briefly attempt to extend the same logic to the other end of the developmental spectrum and describe a potential role of disordered sleep in the pathology of neurodegenerative diseases. We conclude by discussing ongoing studies that might provide a more integrative approach to the study of sleep, plasticity, and neurodevelopmental disorders.

Differential effects of paradoxical sleep deprivation on memory and oxidative stress

Sleep has important functions for every organ in the body and sleep deprivation (SD) leads to disorders that cause irreparable damage. The aim of this study was to investigate behavioral and brain structural alterations in mice deprived of paradoxical sleep for 48 and 72 h. Working memory, aversive memory as well as levels of nitric oxide (NO) and thiobarbituric acid reactive substances (TBARS) in the hippocampus, body striatum, and prefrontal cortex were evaluated. Working memory was affected in the 48- and 72-h SD groups while aversive memory was altered only in the 48-h SD group (p ≤ 0.05). Our findings showed that SD reduces NO levels in most brain areas (p < 0.05): NO levels were unaltered in the striatum of animals sleep-deprived for 48 h. Higher levels of TBARS were observed in all areas of the SD groups (p ≤ 0.05). Thus, we confirmed that SD has duration-dependent effects on behavior as well as on NO and TBARS levels in the brain. Preserved striatum NO levels suggest that this structure is less vulnerable to oxidative stress and is only affected by SD of longer duration. Increased TBARS and reduced NO levels in the hippocampus and prefrontal cortex confirm a central role for both these structures in working memory and aversive memory. Contextual fear conditioning was not affected by longer periods of SD. Thus, our findings suggest that shorter SD time may be more beneficial to avoid aversive memory where this may have implications for the management of posttraumatic stress.

Melatonin ameliorates cognitive impairment induced by sleep deprivation in rats: role of oxidative stress, BDNF and CaMKII

Sleep deprivation (SD) has been shown to induce oxidative stress which causes cognitive impairment. Melatonin, an endogenous potent antioxidant, protects neurons from oxidative stress in many disease models. The present study investigated the effect of melatonin against SD-induced cognitive impairment and attempted to define the possible mechanisms involved. SD was induced in rats using modified multiple platform model. Melatonin (15 mg/kg) was administered to the rats via intraperitoneal injection. The open field test and Morris water maze were used to evaluate cognitive ability. The cerebral cortex (CC) and hippocampus were dissected and homogenized. Nitric oxide (NO) and malondialdehyde (MDA) levels and the superoxide dismutase (SOD) enzyme activity of hippocampal and cortical tissues (10% wet weight per volume) were performed to determine the level of oxidative stress. The expression of brain-derived neurotrophic factor (BDNF) and calcium-calmodulin dependent kinase II (CaMKII) proteins in CC and hippocampus was assayed by means of immunohistochemistry. The results revealed that SD impairs cognitive ability, while melatonin treatment prevented these changes. In addition, melatonin reversed SD-induced changes in NO, MDA and SOD in both of the CC and hippocampus. The results of immunoreactivity showed that SD decreased gray values of BDNF and CaMKII in CC and hippocamal CA1, CA3 and dentate gyrus regions, whereas melatonin improved the gray values. In conclusion, our results suggest that melatonin prevents cognitive impairment induced by SD. The possible mechanism may be attributed to its ability to reduce oxidative stress and increase the levels of CaMKII and BDNF in CC and hippocampus.

Paradoxical sleep deprivation potentiates epilepsy induced by homocysteine thiolactone in adult rats

There is an intriguing and still poorly understood relationship between sleep deprivation and epilepsy. It has recently been shown that paradoxical sleep deprivation decreases levels of homocysteine, an amino acid involved together with its thiolactone metabolite in epileptogenesis. The aim of the present study was to investigate the effects of paradoxical sleep deprivation on homocysteine thiolactone (H)-induced seizures in rats, a model of generalized seizures. Selective deprivation of paradoxical sleep in adult male Wistar rats was achieved by the platform method. Animals with implanted electrodes for electroencephalogram (EEG) registration were assigned to appropriate experimental conditions (dry cage for control, large platform for stress control and small platform for paradoxical sleep deprivation) and 72 h later were intraperitoneally treated with either H (5.5 mmol/kg) or saline (0.9% NaCl). This study showed that paradoxical sleep deprivation increased the incidence and number of H-induced seizure episodes, shortened latency time to seizures and led to significant rates of lethality after H administration, but without effect on the seizure severity. Paradoxical sleep deprivation increased the number and duration of spikes-and-wave discharges, while decreased latency to its appearance in EEG. Judging by the behavioral and EEG findings, it could be concluded that paradoxical sleep deprivation can provoke the expression of factors that can potentiate H-induced seizures in adult rats.

Toxicity of metal oxide nanoparticles in immune cells of the sea urchin

The potential toxicity of stannum dioxide (SnO₂), cerium dioxide (CeO₂) and iron oxide (Fe₃O₄) nanoparticles (NPs) in the marine environment was investigated using the sea urchin, Paracentrotus lividus, as an in vivo model. We found that 5 days after force-feeding of NPs in aqueous solutions, the three NPs presented different toxicity degrees, depending on the considered biomarkers. We examined: 1) the presence of the NPs in the coelomic fluid and the uptake into the immune cells (coelomocytes); 2) the cholinesterase activity and the expression of the stress-related proteins HSC70 and GRP78; 3) the morphological changes affecting cellular compartments, such as the endoplasmic reticulum (ER) and lysosomes. By Environmental Scanning Electron Microscope (ESEM) analysis, coupled with Energy Dispersive X-ray Spectroscopy (EDS) we found that NPs were uptaken inside coelomocytes. The cholinesterases activity, a well known marker of blood intoxication in vertebrates, was greatly reduced in specimens exposed to NPs. We found that levels of stress proteins were down-regulated, matching the observed ER and lysosomes morphological alterations. In conclusion, this is the first study which utilizes the sea urchin as a model organism for biomonitoring the biological impact of NPs and supports the efficacy of the selected biomarkers.

Probucol, a lipid-lowering drug, prevents cognitive and hippocampal synaptic impairments induced by amyloid β peptide in mice

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by synaptic loss and cognitive impairments. The presence of extracellular senile plaques (mainly composed of amyloid-β (Aβ) peptide) is an important molecular hallmark in AD and neuronal damage has been attributed, at least in part, to Aβ-mediated toxicity. Although the molecular mechanisms involved in the pathogenesis of AD are not yet completely understood, several lines of evidence indicate that oxidative stress and cholesterol dyshomeostasis play crucial roles in mediating the synaptic loss and cognitive deficits observed in AD patients. This study evaluated the effects of Probucol, a phenolic lipid-lowering agent with anti-inflammatory and antioxidant properties, on biochemical parameters related to oxidative stress and synaptic function (hippocampal glutathione and synaptophysin levels; glutathione peroxidase, glutathione reductase and acetylcholinesterase activities; lipid peroxidation), as well as on behavioral parameters related to the cognitive function (displaced and new object recognition tasks) in Aβ-exposed mice. Animals were treated with a single intracerebroventricular (i.c.v.) injection of aggregated Aβ(1-40) (400 pmol/site) and, subsequently, received Probucol (10 mg/kg, i.p.) once a day, during the following 2 weeks. At the end of treatments, Aβ(1-40)-exposed animals showed a significant impairment on learning-memory ability, which was paralleled by a significant decrease in hippocampal synaptophysin levels, as well as by an increase in hippocampal acetylcholinesterase activity. Importantly, Probucol treatment blunted the deleterious effects of Aβ(1-40) on learning-memory ability and hippocampal biochemistry. Although Aβ(1-40) treatment did not change hippocampal glutathione levels and glutathione peroxidase (GPx) and glutathione reductase (GR) activities, Aβ(1-40)-exposed animals showed increased hippocampal lipid peroxidation and this event was completely blunted by Probucol treatment. These findings reinforce and extend the notion of the hazardous effects of Aβ(1-40) toward hippocampal synaptic homeostasis and cognitive functions. In addition, the present results indicate that Probucol is able to counteract the cognitive and biochemical impairments induced by i.c.v. Aβ(1-40) administration in mice. The study is the first to report the protective effects of Probucol (a "non-statin cholesterol-lowering drug") against Aβ(1-40)-induced synaptic and behavioral impairments, rendering this compound a promising molecule for further pharmacological studies on the search for therapeutic strategies to treat or prevent AD.

Sleep deprivation under sustained hypoxia protects against oxidative stress

We previously showed that total sleep deprivation increased antioxidant responses in several rat brain regions. We also reported that chronic hypoxia enhanced antioxidant responses and increased oxidative stress in rat cerebellum and pons, relative to normoxic conditions. In the current study, we examined the interaction between these two parameters (sleep and hypoxia). We exposed rats to total sleep deprivation under sustained hypoxia (SDSH) and compared changes in antioxidant responses and oxidative stress markers in the neocortex, hippocampus, brainstem, and cerebellum to those in control animals left undisturbed under either sustained hypoxia (UCSH) or normoxia (UCN). We measured changes in total nitrite levels as an indicator of nitric oxide (NO) production, superoxide dismutase (SOD) activity and total glutathione (GSHt) levels as markers of antioxidant responses, and levels of thiobarbituric acid-reactive substances (TBARS) and protein carbonyls as signs of lipid and protein oxidation products, respectively. We found that acute (6h) SDSH increased NO production in the hippocampus and increased GSHt levels in the neocortex, brainstem, and cerebellum while decreasing hippocampal lipid oxidation. Additionally, we observed increased hexokinase activity in the neocortex of SDSH rats compared to UCSH rats, suggesting that elevated glucose metabolism may be one potential source of the enhanced free radicals produced in this brain region. We conclude that short-term insomnia under hypoxia may serve as an adaptive response to prevent oxidative stress.

Sleep fragmentation induces cognitive deficits via nicotinamide adenine dinucleotide phosphate oxidase-dependent pathways in mouse

RATIONALE

Sleep fragmentation (SF) is one of the major characteristics of sleep apnea, and has been implicated in its morbid consequences, which encompass excessive daytime sleepiness and neurocognitive impairments. We hypothesized that absence of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity is neuroprotective in SF-induced cognitive impairments.

OBJECTIVES

To examine whether increased NADPH oxidase activity may play a role in SF-induced central nervous system dysfunction.

METHODS

The effect of chronic SF during the sleep-predominant period on sleep architecture, sleep latency, spatial memory, and oxidative stress parameters was assessed in mice lacking NADPH oxidase activity (gp91phox-(/Y)) and wild-type littermates.

MEASUREMENTS AND MAIN RESULTS

SF for 15 days was not associated with differences in sleep duration, sleep state distribution, or sleep latency in both gp91phox-(/Y) and control mice. However, on a standard place training task, gp91phox-(/Y) mice displayed normal learning and were protected from the spatial learning deficits observed in wild-type littermates exposed to SF. Moreover, anxiety levels were increased in wild-type mice exposed to SF, whereas no changes emerged in gp91phox-(/Y) mice. Additionally, wild-type mice, but not gp91phox-(/Y) mice, had significantly elevated NADPH oxidase gene expression and activity, and in malondialdehyde and 8-oxo-2'-deoxyguanosine levels in cortical and hippocampal lysates after SF exposures.

CONCLUSIONS

This work substantiates an important role for NADPH oxidase in hippocampal memory impairments induced by SF, modeling sleep apnea. Targeting NADPH oxidase, therefore, is expected to minimize hippocampal impairments from both intermittent hypoxia and SF associated with the disease.

Neurochemical and electrophysiological changes induced by paradoxical sleep deprivation in rats

The present study aims to investigate the effects of paradoxical sleep deprivation (PSD) on the waking EEG and amino acid neurotransmitters in the hippocampus and cortex of rats. Animals were deprived of paradoxical sleep for 72h by using the multiple platform method. The EEG power spectral analysis was carried out to assess the brain's electrophysiological changes due to sleep deprivation. The concentrations of amino acid neurotransmitters were assessed in the hippocampus and cortex using HPLC. Control data showed slight differences from normal animals in the delta, theta and alpha waves while an increase in the beta wave was obtained. After 24h of PSD, delta relative power increased and the rest of EEG wave's power decreased with respect to control. After 48h and 72h the spectral power analysis showed non-significant changes to control. The amino acid neurotransmitter analysis revealed a significant increase in cortical glutamate, glycine and taurine levels while in the hippocampus, glutamate, aspartate, glutamine and glycine levels increased significantly. Both the waking EEG and neurotransmitter analyses suggest that PSD induced neurochemical and electrophysiological changes that may affect brain proper functionality.

Exercise prevents sleep deprivation-associated anxiety-like behavior in rats: potential role of oxidative stress mechanisms

Our previous work suggests that pharmacological induction of oxidative stress causes anxiety-like behavior in rats. Interestingly, sleep deprivation is reported to cause oxidative damage in the brain and is also reported to be anxiogenic. Minimal mechanistic insights are available. In this study, using a behavioral and biochemical approach, we investigated involvement of oxidative stress mechanisms in sleep deprivation-induced anxiety-like behavior of rats and the protective role of treadmill exercise in this process. We report that acute sleep deprivation (SD) increases oxidative stress in the cortex, hippocampus and amygdala while prior treadmill exercise prevents this increase. Serum corticosterones also increase with SD but its levels are normalized in exercised sleep-deprived rats. Also, anxiety-like behavior of rats significantly increases with SD while prior treadmill exercise prevents this increase. Protein expression of two enzymes involved in antioxidant defense, glyoxalase (GLO)-1 and glutathione reductase (GSR)-1 increased after 24h SD in the hippocampus, cortex and amygdala while their levels were normalized in exercised sleep-deprived rats. It is plausible that oxidative stress via regulation of GLO1 and GSR1 is involved in sleep deprivation-induced anxiety-like behavior of rats.