Project description:Sleep deprivation (SD) leads to the spectrum of mood disorders like anxiety, cognitive dysfunctions and motor coordination impairment in many individuals. However, there is no effective pharmacological remedy to negate the effects of SD. The current study examined whether 50% ethanolic extract of Tinospora cordifolia (TCE) can attenuate these negative effects of SD. Three groups of adult Wistar female rats - (1) vehicle treated-sleep undisturbed (VUD), (2) vehicle treated-sleep deprived (VSD) and (3) TCE treated-sleep deprived (TSD) animals were tested behaviorally for cognitive functions, anxiety and motor coordination. TSD animals showed improved behavioral response in EPM and NOR tests for anxiety and cognitive functions, respectively as compared to VSD animals. TCE pretreatment modulated the stress induced-expression of plasticity markers PSA-NCAM, NCAM and GAP-43 along with proteins involved in the maintenance of LTP i.e., CamKII-α and calcineurin (CaN) in hippocampus and PC regions of the brain. Interestingly, contrary to VSD animals, TSD animals showed downregulated expression of inflammatory markers such as CD11b/c, MHC-1 and cytokines along with inhibition of apoptotic markers. This data suggests that TCE alone or in combination with other memory enhancing agents may help in managing sleep deprivation associated stress and improving cognitive functions.
Project description:Sleep benefits the restoration of energy metabolism and thereby supports neuronal plasticity and cognitive behaviors. Sirt6 is a NAD+-dependent protein deacetylase that has been recognized as an essential regulator of energy metabolism because it modulates various transcriptional regulators and metabolic enzymes. The aim of this study was to investigate the influence of Sirt6 on cerebral function after chronic sleep deprivation (CSD). We assigned C57BL/6J mice to control or two CSD groups and subjected them to AAV2/9-CMV-EGFP or AAV2/9-CMV-Sirt6-EGFP infection in the prelimbic cortex (PrL). We then assessed cerebral functional connectivity (FC) using resting-state functional MRI, neuron/astrocyte metabolism using a metabolic kinetics analysis; dendritic spine densities using sparse-labeling; and miniature excitatory postsynaptic currents (mEPSCs) and action potential (AP) firing rates using whole-cell patch-clamp recordings. In addition, we evaluated cognition via a comprehensive set of behavioral tests. Compared with controls, Sirt6 was significantly decreased (P < 0.05) in the PrL after CSD, accompanied by cognitive deficits and decreased FC between the PrL and accumbens nucleus, piriform cortex, motor cortex, somatosensory cortex, olfactory tubercle, insular cortex, and cerebellum. Sirt6 overexpression reversed CSD-induced cognitive impairment and reduced FC. Our analysis of metabolic kinetics using [1-13C] glucose and [2-13C] acetate showed that CSD reduced neuronal Glu4 and GABA2 synthesis, which could be fully restored via forced Sirt6 expression. Furthermore, Sirt6 overexpression reversed CSD-induced decreases in AP firing rates as well as the frequency and amplitude of mEPSCs in PrL pyramidal neurons. These data indicate that Sirt6 can improve cognitive impairment after CSD by regulating the PrL-associated FC network, neuronal glucose metabolism, and glutamatergic neurotransmission. Thus, Sirt6 activation may have potential as a novel strategy for treating sleep disorder-related diseases.
Project description:BackgroundEarly life stress can cause cognitive impairment in aged offspring. Environmental enrichment (EE) is considered to be an effective non-pharmacological treatment for improving cognitive decline. The aim of this research was to evaluate the effect of EE, on cognitive impairment in aged offspring induced by maternal sleep deprivation (MSD) and the underlying mechanisms involved to investigate its potential value in clinical practice.MethodsCD-1 damns were subjected or not to sleep deprivation during late gestation. Twenty-one days after birth, the offspring were assigned to standard or EE cages. At 18 months-old, the learning and memory function of the offspring mice was evaluated using Morris water maze. The hippocampal and prefrontal cortical levels of protein, gene, proinflammation cytokines, and oxidative stress indicators was examined by Western blot, real-time polymerase chain reaction, enzyme linked immunosorbent assay, and biochemical assays.ResultsOffspring in MSD group exhibited declined learning and memory abilities compared with control animals. Moreover, the hippocampal and prefrontal cortical levels of Sirtuin1 (Sirt1), peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α), postsynaptic density protein-95, and synaptophysin were lower and those of proinflammation cytokines higher in the MSD group; meanwhile, the superoxide dismutase content was higher and the malondialdehyde and reactive oxygen species contents were lower. However, these deleterious changes were ameliorated by exposure to EE.ConclusionsEE attenuates MSD-induced cognitive impairment, oxidative stress, and neuroinflammation and reverses the reduction in synaptic protein levels in aged offspring mice via the Sirt1/PGC-1α pathway.
Project description:Disturbed sleep is a common subjective complaint among individuals with anxiety disorders. Sleep deprivation increases general and specific anxiety symptoms among healthy individuals. The amygdala is critical for regulating anxiety and also involved in mediating the effects of emotions on sleep. Neuropeptide S (NPS) and NPS receptors (NPSR) are reported as a novel endogenous arousal and anxiolytic system, but it is unclear yet whether this system is involved in anxiety-like behavior and sleep caused by sleep deprivation, and how it plays anxiolytic effect underlying the comorbid condition. In the present study, we demonstrate that paradoxical sleep deprivation (PSD) induced by modified multiple platform method (MMPM) for 24 h caused anxiety-like behavior, a prolonged sleep latency and subsequent paradoxical sleep (PS) rebound accompanied by an increase in electroencephalogram (EEG) theta (4.5-8.5 Hz) activities across light and dark phase in rats. The increase of PS after PSD was due to an increase of episode number during light phase and both episode number and duration during dark phase. Central action of NPS (1 nmol) attenuated PSD-induced anxiety-like behavior, and altered PSD-induced sleep-wake disturbances through increasing wakefulness, and suppressing PS and EEG theta activities. The reduction in PS time following NPS administration during light phase was because of a decreased episode number. Furthermore, sleep amount in 24 h in PSD rats given NPS was lesser than that given saline. PSD significantly enhanced NPSR mRNA expression level in the amygdala. NPS remarkably increased the number of Fos-ir neurons in the basolateral amygdala (BLA), the central amygdala (CeA) and medial amygdala (MeA). The majority of Fos-ir neurons induced by NPS also expressed NPSR. These results suggest that NPSR upregulation in the amygdala is presumably related to the PSD-induced anxiety-like behavior and sleep disturbances, and that NPS counteracts PSD-induced anxiety-like behavior and sleep disturbances possibly through activating the neurons bearing NPSR in the amygdala. In addition, the little sleep increase in PSD rats treated with NPS suggests that NPS can function as an anxiolytic without causing a subsequent sleep rebound.
Project description:BackgroundSynaptic dysfunction with reduced synaptic protein levels is a core feature of Alzheimer's disease (AD). Synaptic proteins play a central role in memory processing, learning, and AD pathogenesis. Evidence suggests that synaptic proteins in plasma neuronal-derived extracellular vesicles (EVs) are reduced in patients with AD. However, it remains unclear whether levels of synaptic proteins in EVs are associated with hippocampal atrophy of AD and whether upregulating the expression of these synaptic proteins has a beneficial effect on AD.MethodsIn this study, we included 57 patients with AD and 56 healthy controls. We evaluated their brain atrophy through magnetic resonance imaging using the medial temporal lobe atrophy score. We measured the levels of four synaptic proteins, including synaptosome-associated protein 25 (SNAP25), growth-associated protein 43 (GAP43), neurogranin, and synaptotagmin 1 in both plasma neuronal-derived EVs and cerebrospinal fluid (CSF). We further examined the association of synaptic protein levels with brain atrophy. We also evaluated the levels of these synaptic proteins in the brains of 5×FAD mice. Then, we loaded rabies virus glycoprotein-engineered EVs with messenger RNAs (mRNAs) encoding GAP43 and SNAP25 and administered these EVs to 5×FAD mice. After treatment, synaptic proteins, dendritic density, and cognitive function were evaluated.ResultsThe results showed that GAP43, SNAP25, neurogranin, and synaptotagmin 1 were decreased in neuronal-derived EVs but increased in CSF in patients with AD, and the changes corresponded to the severity of brain atrophy. GAP43 and SNAP25 were decreased in the brains of 5×FAD mice. The engineered EVs efficiently and stably delivered these synaptic proteins to the brain, where synaptic protein levels were markedly upregulated. Upregulation of synaptic protein expression could ameliorate cognitive impairment in AD by promoting dendritic density. This marks the first successful delivery of synaptic protein mRNAs via EVs in AD mice, yielding remarkable therapeutic effects.ConclusionsSynaptic proteins are closely related to AD processes. Delivery of synaptic protein mRNAs via EVs stands as a promising effective precision treatment strategy for AD, which significantly advances the current understanding of therapeutic approaches for the disease.
Project description:Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder leading to cognitive decline. Excessive cytosolic calcium (Ca2+) accumulation plays a critical role in the pathogenesis of AD since it activates the NOD-like receptor family, pyrin domain containing 3 (NLRP3), switches the endoplasmic reticulum (ER) unfolded protein response (UPR) toward proapoptotic signaling and promotes Aβ seeding. Herein, a liposomal nanodrug (felodipine@LND) is developed incorporating a calcium channel antagonist felodipine for Alzheimer's disease treatment through a low-intensity pulse ultrasound (LIPUS) irradiation-assisted blood brain barrier (BBB)-crossing drug delivery. The multifunctional felodipine@LND is effectively delivered to diseased brain through applying a LIPUS irradiation to the skull, which resulted in a series of positive effects against AD. Markedly, the nanodrug treatment switched the ER UPR toward antioxidant signaling, prevented the surface translocation of ER calreticulin (CALR) in microglia, and inhibited the NLRP3 activation and Aβ seeding. In addition, it promoted the degradation of damaged mitochondria via mitophagy, thereby inhibiting the neuronal apoptosis. Therefore, the anxiety-like behavior and cognitive impairment of 5xFAD mice with AD is significantly ameliorated, which manifested the potential of LIPUS - assisted BBB-crossing delivery of felodipine@LND to serve as a paradigm for AD therapy based on the well-recognized clinically available felodipine.
Project description:Objective, rapid evaluation of cognitive function is critical for identifying situational impairment due to sleep deprivation. The present study used brain vital sign monitoring to evaluate acute changes in cognitive function for healthy adults. Thirty (30) participants were scanned using portable electroencephalography before and after either a night of regular sleep or a night of total sleep deprivation. Brain vital signs were extracted from three established event-related potential components: (1) the N100 (Auditory sensation); (2) the P300 (Basic attention); and (3) the N400 (Cognitive processing) for all time points. As predicted, the P300 amplitude was significantly reduced in the sleep deprivation group. The findings indicate that it is possible to detect situational cognitive impairment due to sleep deprivation using objective, rapid brain vital sign monitoring.
Project description:Sleep deprivation (SD) has led to a rise in cognitive impairment (CI) cases. Kaempferol (KMP), known for its anti-inflammatory and antiapoptotic properties, holds promise in countering SD-induced CI. Experimental validation using a sleep-deprived CI model confirmed KMP's efficacy in mitigating CI. Immunofluorescence investigations emphasized diminished activation of astrocytes and reduced the proliferation of microglia in the hippocampus of mice subjected to SD. Subsequently, network pharmacological analyses were conducted and found that KMP may be closely related to the mitogen-activated protein kinase (MAPK) pathway in SD-induced CI. The influence of KMP on the MAPK pathway was verified by the observed decrease in the expression of phosphorylated JNK (p-JNK) and p38 (p-p38). Analyzing hippocampal AMPARS and NMDARS expression indicated KMP's ability to enhance GluA1 phosphorylation (Ser831 and Ser845) and GluN2A levels. Patch clamp assays demonstrated heightened excitatory transmitter transmission in the hippocampus, suggesting KMP's positive influence. Overall, KMP combats neuroinflammation via MAPK inhibition, augments synaptic function, and addresses learning and memory dysfunction in sleep-deprived mice.
Project description:REM sleep behavior disorder (RBD) is a parasomnia affecting 33% to 46% of patients with Parkinson's disease (PD). The existence of a unique and specific impaired cognitive profile in PD patients with RBD is still controversial. We extensively assessed cognitive functions to identify whether RBD is associated with more severe cognitive deficits in nondemented patients with PD. One hundred sixty-two participants, including 53 PD patients with RBD, 40 PD patients without RBD, and 69 healthy subjects, underwent polysomnography, a neurological assessment and an extensive neuropsychological exam to assess attention, executive functions, episodic learning and memory, visuospatial abilities, and language. PD patients with RBD had poorer and clinically impaired performance in several cognitive tests compared to PD patients without RBD and healthy subjects. These two latter groups were similar on all cognitive measures. Mild cognitive impairment (MCI) diagnosis frequency was almost threefold higher in PD patients with RBD compared to PD patients without RBD (66% vs. 23%, p < .001). Moreover, subjective cognitive decline was reported in 89% of PD patients with RBD compared to 58% of PD patients without RBD (p = .024). RBD in PD is associated with a more impaired cognitive profile and higher MCI diagnosis frequency, suggesting more severe and widespread neurodegeneration. This patient subgroup and their caregivers should receive targeted medical attention to better detect and monitor impairment and to enable the development of management interventions for cognitive decline and its consequences.
Project description:Excessive stress plays a critical role in the pathogenesis of mood disorders such as depression. Fermented natural products have recently attracted attention because of their health benefits. We evaluated the antidepressant-like efficacy of fermented Perilla frutescens (FPF), and its underlying mechanisms, in sleep deprivation (SD)-induced stress mice. SD-stressed mice revealed a remarkable increase in the immobility time in both forced swimming test and tail suspension test; this increase was ameliorated by treatment with FPF at doses of 100 and 150 mg/kg. FPF treatment also reduced the level of stress hormones such as corticosterone and adrenocorticotropic hormone. Additionally, FPF increased the levels of serotonin and dopamine which were significantly decreased in the brain tissues of SD-stressed mice. The increased expression of proinflammatory cytokines, such as TNF-α and IL1β, and the decreased expression of brain-derived neurotrophic factor (BDNF) in the stressed mice were significantly reversed by FPF treatment. Furthermore, FPF also increased phosphorylation of tropomyosin receptor kinase B (TrkB), extracellular regulated protein kinase (ERK), and cAMP response element binding protein (CREB). Among the six components isolated from FPF, protocatechuic acid and luteolin-7-O-glucuronide exhibited significant antidepressant-like effects, suggesting that they are major active components. These findings suggest that FPF has therapeutic potential for SD-induced stress, by correcting dysfunction of hypothalamic-pituitary-adrenal axis and modulating the BDNF/TrkB/ERK/CREB signaling pathway.