Butylphthalide alleviates sleep deprivation-induced cognitive deficit by regulating Nrf2/HO-1 pathway

Sleep restriction promotes brain oxidative stress and inflammation, and aggravates cognitive impairment in insulin-resistant mice

Sleep deprivation and insulin resistance (IR) are two risk factors for Alzheimer's disease. As the population of people with IR increases and sleep restriction (SR) due to staying up late becomes the "new normal", it is necessary to investigate the effects and molecular pathogenesis of chronic SR on cognitive function in insulin resistance. In this study, 4-week-old mice were fed a high-fat diet (HFD) for 8 weeks to establish IR model, and then the mice were subjected to SR for 21 days, and related indicators were assessed, including cognitive capacity, apoptosis, oxidative stress, glial cell activation, inflammation, blood-brain barrier (BBB) permeability and adiponectin levels, for exploring the potential regulatory mechanisms. Compared with control group, IR mice showed impaired cognitive capacity, meanwhile, SR not only promoted Bax/Bcl2-induced hippocampal neuronal cell apoptosis and Nrf2/HO1- induced oxidative stress, but also increased microglia activation and inflammatory factor levels and BBB permeability, thus aggravating the cognitive impairment in IR mice. Consequently, changing bad living habits and ensuring sufficient sleep are important intervention strategies to moderate the aggravation of IR-induced cognitive impairment.

Sleep and Oxidative Stress: Current Perspectives on the Role of NRF2

Sleep is a fundamental conserved physiological state across evolution, suggesting vital biological functions that are yet to be fully clarified. However, our understanding of the neural and molecular basis of sleep regulation has increased rapidly in recent years. Among various processes implicated in controlling sleep homeostasis, a bidirectional relationship between sleep and oxidative stress has recently emerged. One proposed function of sleep may be the mitigation of oxidative stress in both brain and peripheral tissues, contributing to the clearance of reactive species that accumulate during wakefulness. Conversely, reactive species, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), at physiological levels, may act as signaling agents to regulate redox-sensitive transcriptional factors, enzymes, and other effectors involved in the regulation of sleep. As a primary sensor of intracellular oxidation, the transcription factor NRF2 is emerging as an indispensable component to maintain cellular redox homeostasis during sleep. Indeed, a number of studies have revealed an association between NRF2 dysfunction and the most common sleep conditions, including sleep loss, obstructive sleep apnea, and circadian sleep disturbances. This review examines the evidence of the intricate link between oxidative stress and NRF2 function in the context of sleep, and highlights the potential of NRF2 modulators to alleviate sleep disturbances.

The effect of modified Qiyuan paste on mice with low immunity and sleep deprivation by regulating GABA nerve and immune system

BACKGROUND

Low immunity and sleep disorders are prevalent suboptimal health conditions in contemporary populations, which render them susceptible to the infiltration of pathogenic factors. LJC, which has a long history in traditional Chinese medicine for nourishing the Yin and blood and calming the mind, is obtained by modifying Qiyuan paste. Dendrobium officinale Kimura et Migo has been shown to improve the immune function in sleep-deprived mice. In this study, based on the traditional Chinese medicine theory, LJC was prepared by adding D. officinale Kimura et Migo to Qiyuan paste decoction.

METHODS

Indicators of Yin deficiency syndrome, such as back temperature and grip strength, were measured in each group of mice; furthermore, behavioral tests and pentobarbital sodium-induced sleep tests were performed. An automatic biochemical analyzer, enzyme-linked immunosorbent assay kit, and other methods were used to determine routine blood parameters, serum immunoglobulin (IgG, IgA, and IgM), cont (C3, C4), acid phosphatase (ACP) and lactate dehydrogenase (LDH) levels in the spleen, serum hemolysin, and delayed-type hypersensitivity (DTH) levels. In addition, serum levels of γ-aminobutyric acid (GABA) and glutamate (Glu) were detected using high-performance liquid chromatography (HPLC). Hematoxylin-eosin staining and Nissl staining were used to assess the histological alterations in the hypothalamus tissue. Western blot and immunohistochemistry were used to detect the expressions of the GABA pathway proteins GABRA1, GAD, GAT1, and GABAT1 and those of CD4+ and CD8+ proteins in the thymus and spleen tissues.

RESULTS

The findings indicated that LJC prolonged the sleep duration, improved the pathological changes in the hippocampus, effectively upregulated the GABA content in the serum of mice, downregulated the Glu content and Glu/GABA ratio, enhanced the expressions of GABRA1, GAT1, and GAD, and decreased the expression of GABAT1 to assuage sleep disorders. Importantly, LJC alleviated the damage to the thymus and spleen tissues in the model mice and enhanced the activities of ACP and LDH in the spleen of the immunocompromised mice. Moreover, serum hemolysin levels and serum IgG, IgA, and IgM levels increased after LJC administration, which manifested as increased CD4+ content, decreased CD8+ content, and enhanced DTH response. In addition, LJC significantly increased the levels of complement C3 and C4, increased the number of white blood cells and lymphocytes, and decreased the percentage of neutrophils in the blood.

CONCLUSIONS

LJC can lead to improvements in immunocompromised mice models with insufficient sleep. The underlying mechanism may involve regulation of the GABA/Glu content and the expression levels of GABA metabolism pathway-related proteins in the brain of mice, enhancing their specific and nonspecific immune functions.

Resveratrol Improves Cognitive Function in Post-stroke Depression Rats by Repressing Inflammatory Reactions and Oxidative Stress via the Nrf2/HO-1 Pathway

Post-stroke depression (PSD) is a prevalent mental health issue, and resveratrol (RES) has been implicated in its management. This study aimed to elucidate the impact of RES on PSD. A PSD rat model was established through middle cerebral artery occlusion and chronic unpredictable mild stress. Rats received RES via gavage, and depressive behaviors were evaluated through various measures. Cerebral infarction areas and brain tissue pathology were assessed using TTC and H&E staining. Levels of inflammatory factors (TNF-α/IL-1β/IL-6/IL-10), neurotransmitters (ACH/DA/5-HT/BDNF), and oxidative stress-related indicators (SOD/GSH-Px/MDA), along with the total Nrf2/C-Nrf2/N-Nrf2/HO-1 proteins, were analyzed. The role of the Nrf2/HO-1 pathway was investigated by co-treating rats with RES and either an Nrf2 pathway specific inhibitor (ML385) or activator (dimethyl fumarate). PSD rats exhibited depressive behaviors, disrupted neurotransmitter levels, and oxidative stress markers. RES treatment effectively alleviated these symptoms and activated the Nrf2/HO-1 pathway in PSD rat brain tissues. Co-administration of ML385 attenuated the beneficial effects of RES in PSD rats. Altogether, RES mitigates depressive behaviors, improves cognitive dysfunction, and reduces oxidative stress and inflammatory response in PSD rats. These effects are mediated through the activation of the Nrf2/HO-1 pathway, suggesting RES as a potential therapeutic agent for PSD-related cognitive impairment.

Ginsenoside Rg1 Attenuates Chronic Sleep Deprivation-Induced Hippocampal Mitochondrial Dysfunction and Improves Memory by the AMPK-SIRT3 Pathway

Ginsenoside Rg1 (Rg1) is the main bioactive ginseng component. This study investigates the effects of Rg1 on cognitive deficits triggered by chronic sleep deprivation stress (CSDS) and explores its underlying mechanisms. Rg1 effectively improved spatial working and recognition memory, as evidenced by various behavioral tests. RNA-sequence analysis revealed differential gene expression in the metabolic pathway. Treatment with Rg1 abrogated reductions in SOD and CAT activity, lowered MDA content, and increased Nrf2 and HO-1 protein levels. Rg1 administration alleviated hippocampal mitochondrial dysfunction by restoring normal ultrastructure and enhancing ATP activities and Mfn2 expression while regulating Drp-1 expression. Rg1 mitigated neuronal apoptosis by reducing the Bax/Bcl-2 ratio and the levels of cleaved caspase-3. Additionally, Rg1 upregulated AMPK and SIRT3 protein expressions. These findings suggest that Rg1 has potential as a robust intervention for cognitive dysfunction associated with sleep deprivation, acting through the modulation of mitochondrial function, oxidative stress, apoptosis, and the AMPK-SIRT3 axis.