Increased Salivary IL-1 Beta Level Is Associated with Poor Sleep Quality in University Students

Understanding the connection between stress and sleep: From underlying mechanisms to therapeutic solutions

The objective of this chapter is to navigate through the nexus between stress and sleep, highlighting the neurobiological systems that connect them. Starting with an overview of neuroanatomy and physiology of stress and sleep, with a further detailed breakdown of sleep stages and key neuroanatomical centers that are responsible for sleep and wakefulness. Starting with suprachiasmatic nuclei (SCN) in circadian rhythm and sleep regulation overview, with a center point on the molecular systems including the CLOCK/CRY and BMAL1/2/PER1/2 feedback loops. Following this is the neurobiological of stress, specifically the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic-adrenal (SPA) axis and influence on sleep. Vital neural circuits connecting stress and sleep are examined with the attention of the ventral tegmental area (VTA) GABA-somatostatin neurons and the locus coerules in sleep regulation in response to stress. In addition, neuroinflammation's role occurs through the cytokines IL-1β and TNF-α are investigated as a mediator of sleep disturbances caused by stress. It concludes by summarizing the implications of neuroinflammatory modulation in stress-related psychopathologies, emphasizing the opening this provides for interventions that target this inflammation helping to lighten sleep disorder.

Daily high-frequency transcranial random noise stimulation (hf-tRNS) for sleep disturbances and cognitive dysfunction in patients with mild vascular cognitive impairments: A study protocol for a pilot randomized controlled trial

BACKGROUND

Poor sleep quality is increasingly considered to be an underlying cause of cerebrovascular diseases. This is a slowly progressing condition that gradually leads to vascular cognitive impairment and stroke during ageing. At present, randomized clinical trials examining the non-pharmacological therapies in the management of this comorbidity are very limited. Transcranial current stimulation (tCS) is a non-invasive technology for promoting cognitive function and treating brain disorders. As advanced modalities of tCS, transcranial random noise stimulation (tRNS) and transcranial alternating current stimulation (tACS), could deliver frequency-specific waveforms of currents that can modulate brain activities in a more specific manner.

METHODS AND DESIGN

Chinese individuals between the ages of 60 and 90 years, who are right-handed and have mild vascular cognitive impairment (VCI) with sleep disturbances, will participate in a randomized study. They will undergo a 2-week intervention period where they will be randomly assigned to one of three groups: high-frequency (hf)-tRNS, 40 Hz tACS, or sham tCS. Each group will consist of 15 participants. Before the intervention, high-resolution magnetic resonance imaging (MRI) data will be used to create a computational head model for each participant. This will help identify the treatment target of left inferior parietal lobe (IPL). Throughout the study, comprehensive assessments will be conducted at multiple time points, including baseline, 2nd week, 6th week, and 12th week. These assessments will evaluate various factors such as sleep quality, domain-specific cognitive performance, and actigraphic records. In addition, the participants' adherence to the program and any potential adverse effects will be closely monitored throughout the duration of the intervention.

CONCLUSIONS

The primary objective of this study is to examine the safety, feasibility, and effectiveness of hf-tRNS and 40 Hz tACS interventions targeting left IPL in individuals with mild vascular cognitive impairment (VCI) who experience sleep disturbances and cognitive dysfunction. Additionally, the study seeks to evaluate the program's adherence, tolerability, and any potential adverse effects associated with frequency-specific transcranial current stimulation (tCS). The findings from this research will contribute to a deeper understanding of the intricate relationship between oscillation, sleep, and cognition. Furthermore, the results will provide valuable insights to guide future investigations in the field of sleep medicine and neurodegenerative diseases.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT06169254.

From Garden to Pillow: Understanding the Relationship between Plant-Based Nutrition and Quality of Sleep

The effect of diet on sleep quality has been addressed in many studies; however, whether/how plant-based diets (PBDs) impact sleep-related parameters has not been explored in detail. This review aims to give an overview of the components of PBDs and the possible mechanisms through which PBDs may improve sleep quality. Studies have indicated that diets such as PBDs, which are typically high in fruits, vegetables, nuts, seeds, whole grains, and fiber, are associated with better sleep outcomes, including less fragmented sleep and improved sleep duration. Several mechanisms may explain how PBDs impact and/or improve sleep outcomes. Firstly, PBDs are characteristically rich in certain nutrients, such as magnesium and vitamin B6, which have been associated with improved sleep patterns. Secondly, PBDs are often lower in saturated fats and higher in fiber, which may contribute to better overall health, including sleep quality. Additionally, plant bioactive compounds like phytochemicals and antioxidants in fruits, vegetables, and herbs may have sleep-promoting effects. According to available data, PBD and Mediterranean diet elements promise to enhance sleep quality; however, it is crucial to note that diets should be customized based on each person's needs.

Factors Affecting Sleep Quality among University Medical and Nursing Students: A Study in Two Countries in the Mediterranean Region

Poor sleep quality, a global public health concern, poses a significant burden on individuals, particularly health care university students facing intense academic stress. A three-center cross-sectional study was conducted at the Higher Institute of Nursing and Health Sciences in Tetouan (Morocco), Faculty of Medicine in Tangier (Morocco) and Faculty of Nursing in Valencia (Spain). We collected various data using a sociodemographic questionnaire, the Pittsburgh sleep quality questionnaire, the international physical activity questionnaire (IPAQ) and the smartphone addiction questionnaire short-version (SAS-SV). A total of 1210 students were included in our study (mean age 20.4 years, 67.2% female, nursing students (66.2%) and medical students (33.8%), 76.1% students from Morocco and 33.9% from Spain). Analysis revealed a higher prevalence of poor sleep quality among Moroccans students compared to Spanish ones (p < 0.001), that nursing students showed less favorable sleep quality than medical students (p < 0.011) and that living with a chronic disease was linked to less favorable sleep quality (p < 0.001). Lastly, intense or weak physical activity and smartphone addiction were correlated with poor sleep quality (p < 0.001). In the multivariate analysis, an association persisted between poor sleep quality and factors such as the country of study (Odds ratio (OR): 6.25 [95% Confidence Interval (CI): 4.34-9.09]), involvement in nursing studies (OR: 3.50 [95% CI: 2.36-5.27]), and the presence of chronic diseases (OR: 2.70 [95% CI: 1.72-4.16]), (p < 0.01 each). Our findings highlight the multifaceted factors affecting sleep quality in young university students. The implications underscore the imperative of interventions tailored to this demographic group.

Salivary Brain-Derived Neurotrophic Factor and Cortisol Associated with Psychological Alterations in University Students

INTRODUCTION

Recent evidence reported mental health issues in university students such as anxiety and depressive symptoms and poor sleep quality. Decreased plasma brain-derived neurotrophic factor (BDNF) levels have been proposed as a biomarker of depressive symptoms, whereas cortisol levels are an index of energy mobilization and stress and have been linked to sleep quality. Given that salivary biomarkers represent an interesting new field of research, the aim of this cross-sectional study was to evaluate salivary BDNF and cortisol levels in university students to assess whether they have associations with psychological disturbances such as anxiety and depressive symptoms, sleep quality, and stress level.

METHODS

Salivary BDNF and cortisol levels were measured by specific immunoassays in 70 students whose mental health was also evaluated on the same day through the evaluation of anxiety and depression symptoms (Goldberg scale), sleep quality (Pittsburg Sleep Quality Index and Athens Insomnia Scale), and stress (self-perceived stress scale) and healthy lifestyle habits (alcohol consumption, smoking, regular exercise, and body mass index) were also measured. Multivariate regression analyses were performed in order to identify the strengths of associations between psychological alterations and the concentrations of BDNF, cortisol, and other variables.

RESULTS

Salivary BDNF levels were significantly higher in students with more depressive symptoms, whereas no significant differences were found for cortisol levels. When performing the binary logistic regression model, BDNF levels are included as a predictor variable for a high-depressive-symptoms burden (p < 0.05). Students with worse sleep quality on the Pittsburg Scale had higher cortisol levels (p < 0.05). The subdomains of sleep latency and sleep medication were those significantly associated with salivary cortisol levels in logistic regression analyses (OR = 15.150, p = 0.028). Sleep medication only appeared to be related to cortisol levels (OR = 185.142, p = 0.019). Perceived stress levels and anxiety symptoms were not associated with BDNF or cortisol levels.

CONCLUSIONS

BDNF could play a key role in the pathophysiology of mood-related disorders, and elevation of its peripheral levels could contribute to protecting neurons from the development of mental illness. Higher salivary cortisol levels measured in the morning are accompanied by poorer sleep quality. More research is needed, focusing on salivary biomarkers of disorders related to depressive symptoms and poor sleep quality as a potential tool for the diagnosis and prevention of mental illness.