Understanding neuron-glia crosstalk and biological clocks in insomnia

Transcriptional signatures of cortical structural changes in chronic insomnia disorder

Chronic insomnia disorder (CID) is a multidimensional disease that may influence various levels of brain organization, spanning the macroscopic structural connectome to microscopic gene expression. However, the connection between genomic variations and morphological alterations in CID remains unclear. Here, we investigated brain structural changes in CID patients at the whole-brain level and whether these link to transcriptional characteristics. Brain structural data from 104 CID patients and 102 matched healthy controls (HC) were acquired to examine cortical structural alterations using morphometric similarity (MS) analysis. Partial least squares (PLS) regression and transcriptome data from the Allen Human Brain Atlas were used to extract genomes related to MS changes. Gene-category enrichment analysis (GCEA) was used to identify potential molecular mechanisms behind the observed structural changes. We found that CID patients exhibited MS reductions in the parietal and limbic regions, along with enhancements in the temporal and frontal regions compared to HCs (pFDR < .05). Subsequently, PLS and GCEA revealed that these MS alterations were spatially correlated with a set of genes, especially those significantly correlated with excitatory and inhibitory neurons and chronic neuroinflammation. This neuroimaging-transcriptomic study bridges the gap between cortical structural changes and the molecular mechanisms in CID patients, providing novel insight into the pathophysiology of insomnia and targeted treatments.

Development and validation of a nomogram for sleep disorders among stroke patients

BACKGROUND

Precisely identifying high-risk sleep disorder patients and implementing suitable measures are important for decreasing the incidence of sleep disorders. In this study, a nomogram method was adopted to construct a tool to predict sleep disorders in stroke based on four factors: individual characteristics, treatment-related factors, psychological factors, and family-related factors.

METHODS

A total of 450 stroke patients were continuously diagnosed at the Affiliated Hospital of Nantong University, and the data on participants were randomly distributed into a training set (n = 315) and a validation set (n = 135). Within the training set, using LASSO regression and random forest methods, five optimal predictors of sleep disorders were identified. Five optimal predictors were used to develop a model. The calibration, discrimination, generalization, and clinical applicability of the model were evaluated using calibration curves, receiver operating characteristic (ROC) curves, internal validation, and decision curve analysis (DCA).

RESULTS

We found that the place of residence, average daily infusion time, the Hospital Anxiety and Depression Scale (HADS), the Type D Personality Scale-14 (DS14), and the Fatigue Severity Scale (FSS) were crucial factors associated with sleep disorders. The validation data showed an area under the curve (AUC) of 0.903 compared to 0.899 in the training set. There was an approach to the diagonal in the calibration curve of this model, and the results of DCA noted that it is clinically beneficial across a range of thresholds from 5 % to 99 %.

CONCLUSION

A model was developed to predict sleep disorders among stroke patients to help hospital staff evaluate the risk among patients and screen high-risk patients.

The association between insomnia and cognitive decline: A scoping review

OBJECTIVE

This study aimed to investigate the association between insomnia and cognitive decline to provide insights for clinical interventions and future research.

METHODS

The PubMed, Embase, Web of Science, Scopus, Cochrane Library, and ProQuest databases were systematically searched to identify studies on the association between insomnia and cognitive decline published within the last decade. The quality of the included studies was evaluated, followed by data extraction and summary analysis.

RESULTS

A total of 36 studies were included in the review. Both subjective and objective measures were utilized across 12 indices to assess sleep status, while cognitive function was evaluated using 5 scales and 34 tests. The results revealed a significantly increased risk of cognitive decline or Alzheimer's disease among patients with insomnia, alongside notable impairments in attention, memory, visuospatial abilities, executive function, and verbal memory. Comprehensive assessments of cognitive domains were more sensitive in detecting group differences compared to assessments of specific cognitive sub-functions. Furthermore, MRI analyses showed reduced gray matter volumes in regions such as the prefrontal cortex, cingulate gyrus, temporal lobe, and hippocampus, together with reduced integrity of the white matter in patients with insomnia.

CONCLUSIONS

The findings indicate a potentially bidirectional relationship between insomnia and cognitive decline, suggesting that each may influence and exacerbate the other. Insomnia may increase the risk of cognitive decline and appears to be associated with reduced gray matter volume and compromised white matter integrity in the brain, which could potentially lead to declines in attention, memory, visuospatial abilities, executive function, and verbal memory. Conversely, cognitive decline may contribute to the onset of insomnia, further deteriorating sleep quality. However, further research is necessary to fully comprehend this intricate relationship.

Association between yogurt and dietary supplements containing probiotic consumption with sleep disturbance in US adults: Results from NHANES, 2009-2018

Purpose

Sleep disorders are common globally. Probiotics may improve human microbial diversity, offering potential benefits for sleep disturbances by enhancing sleep quality and reducing disorders. We aimed to use a population-based study to investigate the association between yogurt (a probiotic food) and probiotic consumption with sleep disturbances in US adults.

Methods

A total of 49,693 adults from the 2009-2018 National Health and Nutrition Examination Survey (NHANES) were included in the analyses. Sleep disorders and sleep duration were assessed according to the Sleep Disorders Questionnaire. The Dietary Questionnaire evaluated yogurt and dietary supplements containing probiotic consumption. After adjusting for confounding factors, weighted multivariable logistic regression and subgroup analyses were used to assess the association between yogurt and probiotic consumption and sleep status.

Results

Of the study cohort, 3535 (14.24 %) participants consumed yogurt and/or dietary supplements containing probiotics. The prevalence of sleep disorders was 16.22 %. Only 53.51 % of the participants achieved the recommended amount of sleep (7-9 h), with 6.10 % and 33.48 % having excessive and insufficient sleep duration, respectively. Weighted Logistic regression models indicated a significant association of probiotic intake with a decreased risk of sleep disturbances compared with those without yogurt or probiotic consumption after adjustments. (For sleep disorders: OR: 0.96, 95 % CI 0.94-0.98, P < 0.001; for sleep duration: OR: 0.98, 95 % CI 0.96-1.00, P = 0.081) Moreover, the effect size of the probiotic intake on sleep was especially significant in sex, race, and BMI subgroups.

Conclusion

The present study first indicated that yogurt and probiotic consumption were associated with a reduced risk of sleep disturbances in US adults, particularly among males, whites, and those with a normal BMI. Incorporating yogurt or probiotics into the diet could serve as a public health strategy for improving sleep disturbances, though further investigation into the underlying mechanisms is needed.

The Longevity Med Summit: insights on healthspan from cell to society

In recent years, there has been a paradigm shift with regards to ageing, challenging its traditional perception as an inevitable and natural process. Researchers have collectively identified hallmarks of ageing, nine of which were initially proposed in 2013 and expanded in 2023 to include disabled macroautophagy, chronic inflammation, and dysbiosis, enhancing our understanding of the ageing process at microscopic, cellular, and system-wide levels. Strategies to manipulate these hallmarks present opportunities for slowing, preventing, or reversing age-related diseases, thereby promoting longevity. The interdependence of these hallmarks underscores the necessity of a comprehensive, systems-based approach to address the complex processes contributing to ageing. As a primary risk factor for various diseases, ageing diminishes healthspan, leading to extended periods of compromised health and multiple age-related conditions towards the end of life. The significant gap between healthspan and lifespan holds substantial economic and societal implications. The inaugural Longevity Med Summit (4-5 May 2023, Cascais, Portugal) provided an international forum to discuss the academic and industry landscape of healthy longevity research, preventive medicine and clinical practice to enhance healthspan.

Circadian regulation of microglia function: Potential targets for treatment of Parkinson's Disease

Circadian rhythms are involved in the regulation of many aspects of the body, including cell function, physical activity and disease. Circadian disturbance often predates the typical symptoms of neurodegenerative diseases and is not only a non-motor symptom, but also one of the causes of their occurrence and progression. Glial cells possess circadian clocks that regulate their function to maintain brain development and homeostasis. Emerging evidence suggests that the microglial circadian clock is involved in the regulation of many physiological processes, such as cytokine release, phagocytosis, and nutritional and metabolic support, and that disruption of the microglia clock may affect multiple aspects of Parkinson's disease, especially neuroinflammation and α-synuclein processes. Herein, we review recent advances in the circadian control of microglia function in health and disease, and discuss novel pharmacological interventions for microglial clocks in neurodegenerative disorders.

Dexmedetomidine attenuates sleep deprivation-induced inhibition of hippocampal neurogenesis via VEGF-VEGFR2 signaling and inhibits neuroinflammation

Long periods of sleep deprivation (SD) have serious effects on health. While the α2 adrenoceptor agonist dexmedetomidine (DEX) can improve sleep quality for patients who have insomnia, the effect of DEX on cognition and mechanisms after SD remains elusive. C57BL/6 mice were subjected to 20 h SD daily for seven days. DEX (100 μg/kg) was administered intravenously twice daily (at 1:00 p.m. and 3:00 p.m.) during seven days of SD. We found that systemic administration of DEX attenuated cognitive deficits by performing the Y maze and novel object recognition tests and increased DCX+, SOX2+, Ki67+, and BrdU+NeuN+/NeuN+ cell numbers in the dentate gyrus (DG) region of SD mice by using immunofluorescence, western blotting, and BrdU staining. DEX did not reverse the decrease in DCX+, SOX2+, or Ki67+ cell numbers in SD mice after administration of the α2A-adrenoceptor antagonist BRL-44408. Furthermore, the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR2) expression was upregulated in SD+DEX mice compared with SD mice. Luminex analysis showed that the neurogenic effects of DEX were possibly related to the inhibition of neuroinflammation, including IL-1α, IL-2, CCL5, and CXCL1. Our results suggested that DEX alleviated the impaired learning and memory of SD mice potentially by inducing hippocampal neurogenesis via the VEGF-VEGFR2 signaling pathway and by suppressing neuroinflammation, and α2A adrenoceptors are required for the neurogenic effects of DEX after SD. This novel mechanism may add to our knowledge of DEX in the clinical treatment of impaired memory caused by SD.