Paradoxical sleep deprivation: neurochemical, hormonal and behavioral alterations. Evidence from 30 years of research

Exploring the link between comorbid insomnia and sleep apnea (COMISA) and erectile dysfunction: implications for male sexual health

INTRODUCTION

This review explores the interplay between comorbid insomnia and sleep apnea (COMISA) and erectile dysfunction (ED), 2 conditions that significantly impact men's health. COMISA, a recently recognized condition characterized by the coexistence of insomnia and obstructive sleep apnea, has been shown to disrupt sleep architecture and cause intermittent hypoxia. These disturbances are increasingly linked to the exacerbation of ED, a prevalent issue among men. Understanding the connection between COMISA and ED is crucial for developing integrated treatment approaches that address both sleep and sexual health.

OBJECTIVES

We aim to explore the epidemiological, physiological, and potential therapeutic intersections of COMISA and ED. This review sets out to develop a better understanding of the relationship between these conditions and to emphasize the need for an integrated diagnostic and therapeutic approach that addresses both sleep and sexual health.

METHODS

Through a comprehensive analysis, including a detailed examination of extant studies, we address the hormonal imbalances and alterations in neural pathways that collectively contribute to the complex pathophysiology of ED and how these are particularly susceptible to the concurrent presence of COMISA.

RESULTS

Our analysis indicates that disruptions in sleep architecture and intermittent hypoxia associated with COMISA can exacerbate ED. Hormonal imbalances, endothelial dysfunction, autonomic imbalance, and increased inflammation and oxidative stress are key mechanisms through which COMISA influences ED. These factors collectively impair vascular health, reduce testosterone levels, disrupt neural control of erections, and contribute to the severity of ED.

CONCLUSIONS

This review underscores the necessity for an integrated approach to diagnosis and therapy that considers both sleep and sexual health to improve overall outcomes. These insights should foster a deeper understanding of the relationship between COMISA and ED, encourage further research in this area, and potentially lead to the development of innovative treatment strategies to manage these closely intertwined health concerns.

Unlocking the role of Galectin-3: Implications for sleep disorders and health

Galectin-3 is a member of the lectin family, and is an intriguing protein that is found in diverse tissues across the body. It is known for its multifaceted involvement in various physiological functions, including tissue repair, immune function and neuroinflammation in the central nervous system. It also serves as a paracrine signal, promoting the growth of certain cells and contributing to fibrosis, while higher levels of Galectin-3 in the bloodstream correlate with an increased risk of mortality and cardiovascular disease-related outcomes in the general population. Recent scientific studies have identified a potential link between Galectin-3 and sleep disorders. However, the precise mechanisms through which galectin-3 influences sleep disorders remain an active area of investigation. Although initial studies suggest a potential association between Galectin-3 and sleep disruptions, including conditions, such as insomnia, insufficient sleep time, and obstructive sleep apnea, further research is required to establish a more definitive relationship. This review explores recent findings regarding the potential connection between Galectin-3 and sleep patterns, and offers insights into the complex interplay between this protein and sleep. These discoveries present promising prospects for the development of innovative therapeutic approaches aimed at sleep disorder management, using Galectin-3 as a potential target for interventions or as a biomarker for sleep health.

Chronic sleep deprivation induces erectile dysfunction through increased oxidative stress, apoptosis, endothelial dysfunction, and corporal fibrosis in a rat model

BACKGROUND

Sleep is foundational for nocturnal erections, facilitating nutrient exchange and waste removal, which has brought widespread attention to the relationship between sleep and erectile dysfunction (ED). However, there is currently a lack of basic research confirming whether chronic sleep deprivation (CSD) leads to erectile impairment and its underlying pathological mechanisms.

AIM

The study sought to investigate whether CSD impairs erectile function in rats and the potential tissue damage it may cause in rats.

METHODS

The modified multiple platform method was employed to induce CSD in 14 rats, randomly divided into a platform control group and a CSD group. After 3 weeks, erectile function was evaluated by measuring intracavernosal pressure following cavernous nerve stimulation.

OUTCOMES

Arterial blood samples were then analyzed for testosterone levels, and cavernous tissues were processed for advanced molecular biology assays, including Western blotting and immunofluorescence.

RESULTS

After inducing CSD, rats exhibited a marked reduction in erectile function, yet their serum testosterone levels remained statistically unchanged when compared with the control group. More importantly, rats in the CSD group exhibited a significant increase in oxidative stress levels, accompanied by low expression of HO-1 and high expression of NOX1 and NOX4. Subsequently, elevated oxidative stress induced increased apoptosis in smooth muscle and endothelial cells, as evidenced by significant decreases in CD31 and α-smooth muscle actin expression in the CSD group, demonstrated through Western blotting and immunofluorescence assays. Endothelial cell apoptosis led to a significant decrease in endothelial nitric oxide synthase, resulting in lowered levels of nitric oxide and cyclic guanosine monophosphate, which severely impaired the erectile mechanism. Additionally, activation of the transforming growth factor β1 fibrotic pathway led to increased levels of tissue fibrosis, resulting in irreversible damage to the penile tissue in the CSD group.

CLINICAL IMPLICATIONS

Our study lacks further exploration of the molecular mechanisms linking CSD and ED, representing a future research focus for potential targeted therapies.

STRENGTHS AND LIMITATIONS

Our findings demonstrated that CSD significantly impairs erectile function in rats.

CONCLUSION

CSD severely impairs erectile function in rats. When exposed to CSD, rats exhibit significantly elevated oxidative stress levels, which lead to increased tissue apoptosis, endothelial dysfunction, and ultimately irreversible fibrotic changes in the tissues. Further researches into the potential molecular mechanisms are needed to identify possible therapeutic targets for ED related to CSD.

Erectile dysfunction and sleep related bruxism: An exploratory review of an improbable association

The World Health Organization recognizes sexual health as not merely the absence of disease, but a state of physical, mental, and social well-being in relation to one's sexuality. Achieving sexual satisfaction is pivotal for many individuals, as it significantly contributes to their quality of life. Among various sexual disorders, erectile dysfunction (ED) is notably prevalent, affecting an estimated 10-20 million men in the United States alone. This condition impacts not just the person experiencing it but also significantly influences their intimate connections with partners. Although the causes of ED are multifactorial, recent research highlights a compelling association between sleep disorders, such as sleep deprivation, obstructive sleep apnea (OSA), and insomnia, and the incidence of ED. Furthermore, engaging in night work has been observed to exacerbate the risk of developing ED. One common sleep disorder, sleep related bruxism (SRB), despite its prevalence, has not generally been associated with ED. However, there is some interesting evidence hinting at a potential relationship, including a few studies reporting a high prevalence of ED in individuals with SRB. This review delves into the epidemiological, etiological, and mechanistic links between ED and SRB, aiming to uncover potential intersections between these two conditions. These insights could pave the way for innovative research avenues, possibly exploring treatments like vasodilation medication, that might concurrently address both ED and SRB.

Molecular, Pathophysiological, and Clinical Aspects of Corticosteroid-Induced Neuropsychiatric Effects: From Bench to Bedside

Corticosteroids are frequently prescribed across medical disciplines, yet they are associated with various adverse effects, including neuropsychiatric symptoms, documented since their introduction over 60 years ago. The cellular mechanisms underlying neuropsychiatric symptoms are complex and somewhat obscure, involving multiple pathways. Notably, they include changes in excitability, cellular death of hippocampal and striatal neurons, and increased inflammation and oxidative stress. Clinical presentation varies, encompassing affective disorders (anxiety, euphoria, depression), psychotic episodes, and cognitive deficits. It is crucial to note that these manifestations often go unnoticed by treating physicians, leading to delayed detection of severe symptoms, complications, and underreporting. Discontinuation of corticosteroids constitutes the cornerstone of treatment, resolving symptoms in up to 80% of cases. Although the literature on this topic is scant, isolated cases and limited studies have explored the efficacy of psychotropic medications for symptomatic control and prophylaxis. Pharmacological intervention may be warranted in situations where corticosteroid reduction or withdrawal is not feasible or beneficial for the patient.

Spindle-slow wave coupling and problem-solving skills: impact of age

We examined how aging affects the role of sleep in the consolidation of newly learned cognitive strategies. Forty healthy young adults (20-35 years) and 30 healthy older adults (60-85 years) were included. Participants were trained on the Tower of Hanoi (ToH) task, then, half of each age group were assigned to either the 90-minute nap condition, or stayed awake, before retesting. The temporal co-occurrence between slow waves (SW) and sleep spindles (SP) during non-rapid eye movement sleep was examined as a function of age in relation to memory consolidation of problem-solving skills. We found that despite intact learning, older adults derived a reduced benefit of sleep for problem-solving skills relative to younger adults. As expected, the percentage of coupled spindles was lower in older compared to younger individuals from control to testing sessions. Furthermore, coupled spindles in young adults were more strongly coupled to the SW upstate compared to older individuals. Coupled spindles in older individuals were lower in amplitude (mean area under the curve; μV) compared to the young group. Lastly, there was a significant relationship between offline gains in accuracy on the ToH and percent change of spindles coupled to the upstate of the slow wave in older, but not younger adults. Multiple regression revealed that age accounted for differences in offline gains in accuracy, as did spindle coupling during the upstate. These results suggest that with aging, spindle-slow wave coupling decreases. However, the degree of the preservation of coupling with age correlates with the extent of problem-solving skill consolidation during sleep.

Effects of paradoxical sleep deprivation on oxidative parameters in the serum and brain of mice submitted to the animal model of hyperglycemia

The present study aimed to investigate the effects of paradoxical sleep deprivation (PSD) on behavioral and oxidative stress parameters in the brain and serum of mice submitted to the animal model of hyperglycemia induced by alloxan, mimicking the main symptom of diabetes mellitus (DM). Adults C57BL/6 male and female mice received an injection of alloxan, and ten days later, the animals were submitted to the PSD for 36 h. The animals' behavioral parameters were evaluated in the open-field test. Oxidative stress parameters [Diacetyldichlorofluorescein (DCF), Thiobarbituric acid reactive substances (TBARS), Superoxide dismutase (SOD), and Glutathione] were assessed in the frontal cortex, hippocampus, striatum, and serum. The PSD increased the male and female mice locomotion, but the alloxan's pre-administration prevented the PSD-induced hyperactivity. In addition, the male mice receiving alloxan and submitted to the PSD had elevated latency time in the first quadrant and the number of fecal boli, demonstrating increased anxiety-like behavior. The HPA-axis was hyperactivating in male and female mice pre-administered alloxan and/or PSD-submitted animals. The oxidative stress parameters were also increased in the serum of the animals administered alloxan and/or sleep-deprived mice. Despite alloxan or PSD leading to behavioral or biochemical alterations, the one did not potentiate the other in mice. However, more studies are necessary to identify the link between sleep and hyperglycemia.

The Impact of Sleep: From Ancient Rituals to Modern Challenges

Although sleep is crucial for mental and physical health, insufficient sleep is a growing problem in our modern society. In general, adults need approximately eight hours of sleep per night, but this is often unfeasible nowadays. This sleep restriction has been observed, and it has worsened, throughout the past two centuries; therefore, it is more attributed to socioeconomic changes than to biological adaptations. The most important factors to contribute to this sleep restriction were the popularization of artificial light and industrialization. The present manuscript briefly overviews, from a socioanthropological perspective, the reasons why sleep has been impacted, disclosing its effects on individuals and on society.

Mendelian randomization study supports positive bidirectional causal relationships between genetically predicted insomnia symptom and liability to benign prostatic hyperplasia

BACKGROUND

Sleep quality may be related to benign prostatic hyperplasia (BPH), however causal associations have not been established. This study aimed to evaluate causal relationships between six sleep traits ([i] day time napping, [ii] daytime sleepiness, [iii] insomnia, [iv] long sleep duration, [v] short sleep duration, and [vi] sleep duration per hour) and BPH through a bidirectional Mendelian randomization (MR) study.

METHODS

Genome-wide association summary statistics of sleep traits and BPH were downloaded from public databases. Inverse variance weighting (IVW) was used as the main approach for causal inference. For causal estimates identified by IVW, various sensitivity analyses were performed to assess the reliability of the results: (i) four additional MR methods to complement IVW; (ii) Cochran's Q test to assess heterogeneity; (iii) MR-Egger intercept test and MR-PRESSO global test to assess horizontal pleiotropy; and (iv) leave-one-out method to assess stability.

RESULTS

Forward MR analyses indicated that genetically predicted insomnia symptom significantly increased BPH risk (OR = 1.267, 95% CI: 1.003-1.601, P = 0.048), while reverse MR analyses identified that genetically predicted liability to BPH significantly increased the incidence of insomnia (OR = 1.026, 95% CI: 1.000-1.052, P = 0.048). In a replicate MR analysis based on summary statistics including exclusively male participants, the finding of increased risk of BPH due to genetically predicted insomnia symptom was further validated (OR = 1.488, 95% CI: 1.096-2.022, P = 0.011). No further causal links were identified. In addition, sensitivity tests demonstrated the reliability of the MR results.

CONCLUSION

This study identified that a higher prevalence of genetically predicted insomnia symptoms may significantly increase the risk of BPH, while genetically predicted liability to BPH may in turn increase the incidence of insomnia symptom. Therefore, improving sleep quality and reducing the risk of insomnia could be a crucial approach for the prevention of BPH.

Understanding Sexual Parasomnias: A Review of the Current Literature on Their Nature, Diagnosis, Impacts, and Management

Sexual behavior during sleep, known as sexual parasomnias, has captured the interest of researchers and clinicians. These parasomnias involve various sexual activities that occur unconsciously during sleep. Although relatively rare, they can profoundly affect well-being and relationships and can carry legal consequences. Understanding their nature, prevalence, and causes is crucial for advancing knowledge in this field. This article revisits the topic of sexsomnia, presenting new data and discussing cases published from 2007 to 2023. By analyzing these cases, we aim to enhance recognition, diagnosis, and management of sexsomnia, reducing stigma and providing better support for affected individuals.

Exploring the potential relationships among obstructive sleep apnea, erectile dysfunction, and gut microbiota: a narrative review

INTRODUCTION

Poor sleep quality is closely associated with comorbidities affecting a multitude of organ systems. Among the sleep disorders in the population, there has recently been an increase in the prevalence of obstructive sleep apnea (OSA), which has particularly affected men. The intermittent hypoxia and sleep fragmentation associated with OSA can result in the manifestation or aggravation of a number of pathophysiologic conditions, including the impairment of reproductive function in men and women. In this context, erectile dysfunction (ED) is of particular concern. Other consequences of OSA are changes in the gastrointestinal microbiota, with the resultant dysbiosis having potentially harmful consequences that promote downstream exacerbation of various comorbidities.

OBJECTIVES

This narrative review aims to explore the potential relationships among ED, gut microbiota, and OSA.

METHODS

A search of the relevant literature was performed in the PubMed, Embase, Medline, and Web of Science databases.

RESULTS

Sleep is important for regulating the body's functions, and sleep deprivation can negatively affect health. OSA can damage organic functions, including reproductive function, and can lead to ED. Restoring the microbiota and improving sleep can help to improve sexual function or reverse ED and enhance other associated conditions mediated through the gut-brain axis relationship. Probiotics and prebiotics can be used as supportive strategies in the prevention and treatment of OSA, as they help to reduce systemic inflammation and improve intestinal barrier function.

CONCLUSION

A good diet, a healthy lifestyle, and proper bowel function are essential in controlling depression and several other pathologies. Modulating the gut microbiota through probiotics and prebiotics can provide a viable strategy for developing new therapeutic options in treating many conditions. A better understanding of these a priori unrelated phenomena would foster our understanding of the effects of OSA on human fertility and how changes in gut microbiota may play a role.

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.

Rapid eye movement sleep loss associated cytomorphometric changes and neurodegeneration

Rapid eye movement sleep (REMS) is essential for leading normal healthy living at least in higher-order mammals, including humans. In this review, we briefly survey the available literature for evidence linking cytomorphometric changes in the brain due to loss of REMS. As a mechanism of action, we add evidence that REMS loss elevates noradrenaline (NA) levels in the brain, which affects neuronal cytomorphology. These changes may be a compensatory mechanism as the changes return to normal after the subjects recover from the loss of REMS or if during REMS deprivation, the subjects are treated with NA-adrenoceptor antagonist prazosin (PRZ). We had proposed earlier that one of the fundamental functions of REMS is to maintain the level of NA in the brain. We elaborate on this idea to propose that if REMS loss continues without recovery, the sustained level of NA breaks down neurophysiologically active compensatory mechanism/s starting with changes in the neuronal cytomorphology, followed by their degeneration, leading to acute and chronic pathological conditions. Identification of neuronal cytomorphological changes could prove to be of significance for predicting future neuronal (brain) damage as well as an indicator for REMS health. Although current brain imaging techniques may not enable us to visualize changes in neuronal cytomorphology, given the rapid technological progress including use of artificial intelligence, we are optimistic that it may be a reality soon. Finally, we propose that maintenance of optimum REMS must be considered a criterion for leading a healthy life.

Sleep Deprivation-Induced Oxidative Stress in Rat Models: A Scoping Systematic Review

Sleep deprivation is highly prevalent in the modern world, possibly reaching epidemic proportions. While multiple theories regarding the roles of sleep exist (inactivity, energy conservation, restoration, brain plasticity and antioxidant), multiple unknowns still remain regarding the proposed antioxidant roles of sleep. The existing experimental evidence is often contradicting, with studies pointing both toward and against the presence of oxidative stress after sleep deprivation. The main goals of this review were to analyze the existing experimental data regarding the relationship between sleep deprivation and oxidative stress, to attempt to further clarify multiple aspects surrounding this relationship and to identify current knowledge gaps. Systematic searches were conducted in three major online databases for experimental studies performed on rat models with oxidative stress measurements, published between 2015 and 2022. A total of 54 studies were included in the review. Most results seem to point to changes in oxidative stress parameters after sleep deprivation, further suggesting an antioxidant role of sleep. Alterations in these parameters were observed in both paradoxical and total sleep deprivation protocols and in multiple rat strains. Furthermore, the effects of sleep deprivation seem to extend beyond the central nervous system, affecting multiple other body sites in the periphery. Sleep recovery seems to be characterized by an increased variability, with the presence of both normalizations in some parameters and long-lasting changes after sleep deprivation. Surprisingly, most studies revealed the presence of a stress response following sleep deprivation. However, the origin and the impact of the stress response during sleep deprivation remain somewhat unclear. While a definitive exclusion of the influence of the sleep deprivation protocol on the stress response is not possible, the available data seem to suggest that the observed stress response may be determined by sleep deprivation itself as opposed to the experimental conditions. Due to this fact, the observed oxidative changes could be attributed directly to sleep deprivation.

Association between sleep quality and benign prostate hyperplasia among middle-aged and older men in India

BACKGROUND

The association between sleep quality and benign prostate hyperplasia (BPH) has rarely been studied. The aim of this study was to examine the relationship between sleep quality and BPH among middle-aged and older men in India.

METHODS

This study used data from men over 45 years old in Wave 1 (2017-2018) of the Longitudinal Aging Study in India (LASI). Benign prostate hyperplasia was self-reported, and sleep symptoms were assessed using five questions modified from the Jenkins Sleep Scale. A total of 30,909 male participants were finally included. Multivariate logistic regression analysis, subgroup analysis, and interaction tests were performed.

RESULTS

Total 453 (1.49%) men reported benign prostatic hyperplasia and have higher sleep quality score (9.25 ± 3.89 vs. 8.13 ± 3.46). The results revealed that the sleep quality score and risk of benign prostatic hyperplasia were significantly correlated after adjusting for all confounding factors (OR:1.057, 95% CI: 1.031-1.084, p < 0.001]. After dividing people into four groups based on the quartile of sleep quality scores, compared with the first quartile group, the third quartile group was 1.32 times, and the fourth quartile group was 1.615 times more likely to develop benign prostate hyperplasia. A significant interaction effect of alcohol consumption was observed. (p for interaction < 0.05).

CONCLUSION

Worse sleep quality was significantly associated with a higher incidence of benign prostatic hyperplasia among middle-aged and older Indian men. A further prospective study is needed to clarify this association and explore potential mechanisms.

Sleep disturbance and gastrointestinal cancer risk: a literature review

Sleep, accounting for roughly one-third of a person's life, plays an important role in human health. Despite the close association between sleep patterns and medical diseases proven by several studies, it has been neglected in recent years. Presently, all societies are facing the most challenging health-threatening disease, cancer. Among all cancer types, gastrointestinal (GI) cancers, especially colorectal type, seem to be one of the most relevant to an individual's lifestyle; thus, they can be prevented by modifying behaviors most of the time. Previous studies have shown that disruption of the 24-h sleep-wake cycle increases the chance of colorectal cancer, which can be due to exposure to artificial light at night and some complex genetic and hormone-mediated mechanisms. There has also been some evidence showing the possible associations between other aspects of sleep such as sleep duration or some sleep disorders and GI cancer risk. This review brings some information together and presents a detailed discussion of the possible role of sleep patterns in GI malignancy initiation.

The relationship between fatigue, sleep quality, resilience, and the risk of postpartum depression: an emphasis on maternal mental health

BACKGROUND

Several factors can contribute to the development of postpartum depression (PPD) and negatively affect mothers' mental and physical well-being. The objective of this study was to determine the relationship between fatigue, sleep quality, resilience, and the risk of PPD development.

METHODS

A cross-sectional study was conducted using an online questionnaire distributed to mothers during their postpartum period. The risk of PPD was assessed using the Edinburgh Postnatal Depression Scale (EPDS), postpartum fatigue (PPF) was assessed using the Fatigue Severity Scale (FSS), sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and resilience was assessed using the Brief Resilience Scale (BRS). The Pearson correlation coefficient was calculated to determine the relationship between the study variables. Simple and multiple linear regression analyses were performed to explain the contributions of PPF, sleep quality, and resilience as independent predictors of PPD development.

RESULTS

A total of 1409 postpartum women were included in the analysis, with 75% of the participants reporting a risk of PPD, 61% reporting PPF, 97% reporting having sleep problems, and 36% being in the "low resilience level" category. In terms of correlations, the scores of FSS and the PSQI showed moderate positive relationships with the EPDS scores (r = 0.344 and r = 0.447, respectively, p = .000). The BRS scores were negatively associated with the EPDS scores (r = -0.530, p = 0.000). Fatigue, sleep quality, and resilience were predictors of depressive symptoms (β = 0.127, β = 0.262, and β = -0.393, respectively, R² = 0.37, p = 0.000). The association remained significant in the regression model after adjusting for mother's age, mother's BMI, child's age, smoking status, full-term pregnancy, having a chronic disease, and taking anti-depressant.

CONCLUSIONS

Mothers with higher levels of fatigue, poor sleep quality, and low resilience levels were at high risk of developing PPD. Healthcare providers should identify these factors and thus set better rehabilitation goals to improve overall maternal health.

Sleep loss in male rats contributes more to weight gain during sleep disruption than stress assessed by corticosterone

Sleep disruption (SD) promotes stress which may mediate the effect of SD induced by noise on bodyweight gain and food intake. We determined if the change in bodyweight during SD caused by noise was driven by stress (assessed by corticosterone) and whether the effects of noise on SD, stress and bodyweight were specific to the method of SD or a consequence of SD per se. We isolated stress from SD due to noise by exposing rats to noise during the darkphase to test whether darkphase noise stimulated weight gain, stress and food intake. Male Sprague-Dawley rats slept undisturbed, were exposed to noise during both circadian phases (lightphase vs darkphase) and lightphase gentle handling. Bodyweight, food intake, physical activity, vigilance states, and plasma corticosterone were determined. Darkphase noise did not affect vigilance states. Unlike lightphase noise, darkphase noise and lightphase gentle handling did not stimulate weight gain or food intake. Only gentle handling significantly increased corticosterone levels. Noise during the lightphase increasesed weight gain and food intake by causing SD and these effects were not driven by stress as assessed by corticosterone. These results may have significant implications for developing translational models of insomnia-induced obesity in humans.

Association of sleep quality with lower urinary tract symptoms/benign prostatic hyperplasia among men in China: A cross-sectional study

Objective

As the population aged, voiding dysfunction has been steadily rising among males during the past decade. Increasing evidence showed that sleep disorders are associated with an increasing risk of various diseases, but the association between sleep disorders and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) among Chinese males have not been well characterized.

Materials and methods

We conducted a cross-sectional analysis of data from West China Natural Population Cohort Study (WCNPCS) 2019-2021. Sleep quality was assessed by Pittsburgh sleep quality index (PSQI) in Chinese version. LUTS/BPH as a dependent variable of a binary variable, assessed by a self-reported questionnaire. Multivariate logistic regression analysis were performed to evaluate the correlation between sleep disorders and the risk of LUTS/BPH after adjusting for confounding factors.

Results

11,824 eligible Chinese men participated in this cross-sectional survey. In multivariate logistic regression analysis, after adjusting for confounding variables, global PSQI score (OR: 1.257, 1.119-1.411, p < 0.001) and its six compounds (Subjective sleep quality: OR: 1.376, 1.004-1.886, p = 0.048; Sleep latency: OR: 0.656, 0.557-0.773, p < 0.001; Sleep duration: OR: 1.441, 1.189-1.745, p < 0.001; Habitual sleep efficiency: OR: 1.369, 1.193-1.570, p < 0.001; Daytime dysfunction: OR: 1.702, 1.278-2.267, p < 0.001) except the use of sleep drug subgroup were significantly positively correlated with LUTS/BPH prevalence. Significant interaction effects were observed in age subgroups (age-young group: age < 51; age-middle group: 51 ≤ age ≤ 61; age-older group: age > 61) (P < 0.05). Among older participants, sleep disorders were more significantly associated with the risk of LUTS/BPH.

Conclusion

There was a significant association between poor sleep quality and increased prevalence of LUTS/BPH, especially among the elderly male population, suggesting an important role of healthy sleep in reducing prostate disease burden.

Insomnia Complaints and Perceived Immune Fitness in Young Adults with and without Self-Reported Impaired Wound Healing

Background and Objectives: Adequate sleep and an effective immune system are both essential to maintain a good health status. The current study aimed to determine the nature of insomnia complaints and perceived immune fitness among Dutch young adults with and without self-reported impaired wound healing. Materials and Methods: A total of (n = 2033) Dutch students (83.8% women) completed an online survey. Perceived immune fitness was assessed with a single-item scale and insomnia complaints with the SLEEP-50 insomnia subscale. The sample comprised a control group without self-reported impaired wound healing (n = 1622), a wound infection (WI) group (n = 69), a slow healing wounds (SHW) group (n = 250), and a COMBI group that experienced both WI and SHW (n = 92). Results: Comparisons with the control group revealed that individuals of the SHW and COMBI groups reported significantly poorer perceived immune functioning, increased insomnia complaints and daytime fatigue, and poorer sleep quality. Conclusions: Individuals with self-reported impaired wound healing have a poorer perceived immune functioning, increased insomnia complaints, daytime fatigue, and poorer sleep quality.

Sleep disorders and prostate cancer prognosis: biology, epidemiology, and association with cancer development risk

Sleep is crucial for the maintenance of health and well-being. Sleep disorders can result in physiological consequences and are associated with several health issues, including cancer. Cancer is one of the most significant health problems in the world. In Western countries, prostate cancer is the most prevalent noncutaneous cancer among men. Epidemiological studies showed that one in nine men will have this disease during their life. Many factors influence prostate cancer and the tumor niche, including endogenous hormones, family history, diet, and gene mutations. Disruption of the circadian cycle by sleep disorders or other factors has been suggested as a novel and important risk factor for prostate cancer and its tumorigenesis. This review presents information regarding the epidemiological and biological aspects of prostate cancer, and discusses the impact of sleep physiology and sleep disorders on this type of cancer, highlighting possible associations with risk of cancer development.

Interactions between Sleep and Emotions in Humans and Animal Models

Recently, increased interest and efforts were observed in describing the possible interaction between sleep and emotions. Human and animal model studies addressed the implication of both sleep patterns and emotional processing in neurophysiology and neuropathology in suggesting a bidirectional interaction intimately modulated by complex mechanisms and factors. In this context, we aimed to discuss recent evidence and possible mechanisms implicated in this interaction, as provided by both human and animal models in studies. In addition, considering the affective component of brain physiological patterns, we aimed to find reasonable evidence in describing the two-way association between comorbid sleep impairments and psychiatric disorders. The main scientific literature databases (PubMed/Medline, Web of Science) were screened with keyword combinations for relevant content taking into consideration only English written papers and the inclusion and exclusion criteria, according to PRISMA guidelines. We found that a strong modulatory interaction between sleep processes and emotional states resides on the activity of several key brain structures, such as the amygdala, prefrontal cortex, hippocampus, and brainstem nuclei. In addition, evidence suggested that physiologically and behaviorally related mechanisms of sleep are intimately interacting with emotional perception and processing which could advise the key role of sleep in the unconscious character of emotional processes. However, further studies are needed to explain and correlate the functional analysis with causative and protective factors of sleep impairments and negative emotional modulation on neurophysiologic processing, mental health, and clinical contexts.

Changes in telomere length and serum neurofilament light chain levels in female patients with chronic insomnia disorder

STUDY OBJECTIVES

The aims of this study were to explore changes in the telomere length (relative telomere repeat copy/single-copy gene [T/S ratio]) and serum neurofilament light chain (sNfL) levels in female patients with chronic insomnia disorder (CID), examine their relationships with emotional abnormalities and cognitive impairment, and determine whether these 2 indicators were independently associated with sleep quality.

METHODS

The CID group contained 80 patients diagnosed with CID, and 51 individuals constituted a healthy control group. Participants completed sleep, emotion, and cognition assessments. Telomere length was detected through quantitative real-time polymerase chain reaction. Enzyme-linked immunosorbent assay was used to determine sNfL concentrations.

RESULTS

Relative to the healthy control group, the CID group had elevated Pittsburgh Sleep Quality Index, Hamilton Anxiety Scale-14, and Hamilton Depression Rating Scale-17 scores and reduced Montreal Cognitive Assessment scale scores, a decreased T/S ratio, and an increased sNfL concentration. Subgroup analysis according to various CID-associated sleep factors showed that poor sleep performance corresponded to a lower T/S ratio. Higher anxiety levels and more cognitive dysfunction correlated with shorter telomere lengths. The T/S ratio negatively correlated with age, whereas the sNfL concentration positively correlated with age in the CID group. The Pittsburgh Sleep Quality Index score negatively correlated with the T/S ratio but did not correlate with sNfL levels. Multiple linear regression analysis showed that the T/S ratio had a negative and independent effect on Pittsburgh Sleep Quality Index scores.

CONCLUSIONS

The CID group had shorter telomeres and higher sNfL concentrations, and reduced telomere length independently affected sleep quality.

CITATION

Ren C-Y, Liu P-P, Li J, et al. Changes in telomere length and serum neurofilament light chain levels in female patients with chronic insomnia disorder. J Clin Sleep Med. 2022;18(2):383-392.

The impact of pain and nocturnal cramps on sleep quality in Charcot Marie Tooth disease: a case-control study

Introduction

Charcot-Marie-Tooth disease is an inherited neuropathy that presents two main forms - type 1 and type 2 -, differentiated by the speed of the nervous conduction. Our goal was to assess sleep in Charcot-Marie-Tooth disease and its relationship with pain perception and nocturnal cramps.

Material and Methods

This was a case-control study. The case group was composed of 10 volunteers diagnosed with the type 1 and 23 with the type 2. The control group was composed of 22 individuals from the same family matched by age and gender. Volunteers underwent clinical screening to assess the presence of nocturnal cramps and filled the brief pain inventory, the Chalder fatigue scale, the Epworth sleepiness scale, and the Pittsburgh sleep quality index. Sleep was evaluated by actigraphy.

Results

Type 2 patients presented a more severe perception of pain and fatigue, more time spend awake after sleep onset, and had lower sleep efficiency. The individuals who reported nocturnal cramps also had worse perception of pain, reduced sleep latency, and increased sleep fragmentation.

Conclusion

The Charcot-Marie-Tooth type 2 was related with worse sleep quality, perception of pain, and fatigue and these parameters were negatively related.

Effect of melatonin supplementation on sleep quality: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The Present study was conducted to systematically review the effect of the melatonin on sleep quality. We summarized evidence from randomized clinical trials (RCTs) that investigated the effects of melatonin on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) in adults with various diseases.

METHODS

The literature searches of English publications in MEDLINE and EMBASE databases were performed up June 2020. Results were summarized as mean differences (MD) with 95% confidence intervals (CI) using random effects model (DerSimonian-Laird method). Heterogeneity among studies was evaluated by the Cochrane Q test and I-squared (I2). To determine the predefined sources of heterogeneity, subgroup analysis was performed.

RESULTS

Of 2642 papers, 23 RCTs met inclusion criteria. Our results indicated that melatonin had significant effect on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) (WMD: - 1.24; 95% CI - 1.77, - 0.71, p = 0.000). There was significant heterogeneity between studies (I² = 80.7%, p = 0.000). Subgroup analysis based on health status and kind of intervention were potential between-study heterogeneity. Subgroup analysis based on health status revealed melatonin intervention in subjects with Respiratory diseases (WMD: - 2.20; 95% CI - 2.97, - 1.44, p = 0.000), Metabolic disorders (WMD: - 2.74; 95% CI - 3.48, - 2.00, p = 0.000) and sleep disorders (WMD: - 0.67; 95% CI - 0.98, - 0.37, p = 0.000) has significant effect on sleep quality.

CONCLUSION

We found that the treatment with exogenous melatonin has positive effects on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) in adult. In adults with respiratory diseases, metabolic disorders, primary sleep disorders, not with mental disorders, neurodegenerative diseases and other diseases.

The Association Between Regular Physical Exercise, Sleep Patterns, Fasting, and Autophagy for Healthy Longevity and Well-Being: A Narrative Review

This narrative review of the literature assessed whether regular physical exercise and sleep patterns, fasting and autophagy, altogether can be an adequate strategy for achieving healthy longevity and well-being within different stage of life. There are a large number of studies dealing with well-being and healthy longevity; however, few of them have given us a specific formula for how to live long and healthy. Despite all the advances that have been made to create adequate physical exercise programs, sleep patterns or nutritional protocols, the relation between different types of fasting, nutritional supplementation as well as regular physical exercise and sleep patterns have not yet been satisfactorily resolved to cause the best effects of autophagy and, therefore, well-being and healthy longevity. In this way, future studies should clarify more efficiently the relationship between these variables to understand the association between regular physical exercise, sleep patterns, fasting and autophagy for healthy longevity and well-being.

Application of armodafinil-loaded microneedle patches against the negative influence induced by sleep deprivation

Cognition maintenance is essential for healthy and safe life if sleep deprivation happens. Armodafinil is a wake-promoting agent against sleep deprivation related disorders. However, only the tablet formulation is available, which may limit its potential in some circumstances. Here, we report the synthesis of a new formulation of armodafinil, microneedle patches, which can be conveniently used by any individual and removed in time if not wanted. To produce the needles of higher mechanical strength and higher drug loading, polyvinylpyrrolidone (PVP) K90 was used to fabricate armodafinil-loaded microneedles by applying the mold casting method after dissolving in methanol and drying. The higher mechanical strength was validated by COMSOL Multiphysics® software stimulation and universal mechanical testing machines. The obtained armodafinil microneedles can withstand a force of 70 N and penetrate the skin to a depth of 230 μm, and quickly released the drug within 1.5 h in vitro. The pharmacokinetic analysis showed that microneedle administration can maintain a more lasting and stable blood concentration as compared to oral administration. After the treatment of sleep deprived mice with microneedles, the in vivo pharmacodynamics study clearly demonstrated that armodafinil microneedles could eliminate the effects of sleep deprivation and improve the cognitive functions of sleep-deprived mice. A self-administered, high drug-loaded microneedle patch were prepared successfully, which appeared to be highly promising in preserving cognition by transdermal administration.

Sleep Patterns and Their Association with Blood Pressure and Heart Rate Variability Parameters in Young Saudi Females

Objectives

Disturbed sleep patterns might alter the autonomic tone and lead to various cardiovascular morbidities. This study aimed to determine sleep patterns (quality, duration, efficiency and daytime sleepiness) and explore their association with blood pressure (BP) and heart rate variability (HRV) in apparently healthy, young Saudi females.

Methods

This cross-sectional study was conducted in the Department of Physiology, Imam Abdulrahman Bin Faisal University, Saudi Arabia between March 2019 and December 2019. Self-reported Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale questionnaires were used to collect data. In addition, the participants’ BP and HRV was measured. Based on the cut-off values of sleep quality, duration, efficiency and daytime sleepiness scores, participants were categorised into groups. HRV and BP were compared between the groups by a t-test/one-way ANOVA.

Results

A total of 98 participants were included in this study (response rate: 72.6%). Poor sleep patterns (quality, duration and efficiency) were observed, but no association was found with BP and HRV parameters among groups with different sleep quality, duration and efficiency. Systolic BP was significantly increased in the moderate to severe daytime sleepiness group (P = 0.039). Dozing off as a passenger in a car, in the afternoon and after lunch were negatively correlated with HRV parameters (P <0.05).

Conclusion

Sleep quality, duration and efficiency were not found to be statistically significant, but various dozing-off situations were associated with fluctuations in HRV parameters. Daytime sleepiness may augment sympathetic responses in apparently healthy female participants.

Sleep in Older Adults and Its Possible Relations With COVID-19

Since the beginning of the COVID-19 pandemic, older adults have been found to be a highly vulnerable group, with a higher prevalence of severe cases and negative outcomes. Research has focused on the reasons why older adults are at greater risk; Sleep-related factors have been suggested as one possible explanation for this. An individual's sleep pattern undergoes significant changes over the course of their life. In older adults a specific sleep profile can be observed, one characterized by advanced sleep timing, a morningness preference, longer sleep-onset latency, shorter overall sleep duration, increased sleep fragmentation, reduced slow-wave sleep and, increased wake time after sleep onset. Additionally, an increased prevalence of sleep disorders can be observed, such as obstructive sleep apnea and insomnia. Previous research has already linked sleep disorders (especially sleep apnea) with COVID-19, but few studies have focused specifically on the older population. We believe that the intrinsic sleep patterns of older adults, and the prevalence of sleep disorders in this population, may be important factors that could explain why they are at a greater risk of negative COVID-19 outcomes. In this review, we discuss the relationship between sleep and COVID-19 among older adults, focusing on three different aspects: (1) Sleep-related issues that might increase the likelihood of getting infected by SARS-COV-2; (2) Sleep disturbances that might increase the predisposition to worse COVID-19 prognosis and outcomes; and (3) COVID-19-related aspects affecting community-dwelling older adults, such as social isolation, quarantine, and home confinement, among others, that might impact sleep.

A meta-analysis of the diagnostic value of NoSAS in patients with sleep apnea syndrome

OBJECTIVE

The NoSAS score is a new tool widely used in recent years to screen for obstructive sleep apnea. A number of studies have shown that the NoSAS score is more accurate than previous tools, such as the Berlin, STOP-Bang, and STOP questionnaires. Therefore, this meta-analysis assessed the diagnostic value of the NoSAS score for sleep apnea syndrome in comparison to polysomnography.

METHODS

Two researchers searched the PubMed, EMBASE, Cochrane, and Web of Science databases through November 13, 2020. This paper used Endnote9.3 software to manage the literature and RevMan 5.3 and STATA12.0 software to perform the meta-analysis.

RESULTS

A total of 10 studies were included in this meta-analysis, including 14,510 patients. The meta-analysis showed that the pooled sensitivity was 0.798 (95% CI 0.757, 0.833), the pooled specificity was 0.582 (95% CI 0.510, 0.651), the positive likelihood ratio was 1.909 (95% CI 1.652, 2.206), the negative likelihood ratio was 0.347 (95% CI 0.300, 0.403), the diagnostic OR was 5.495 (95% CI 4.348, 6.945), and the area under the SROC curve was 0.77 (95% CI 0.73, 0.80). The NoSAS score has good efficacy in identifying patients likely to have obstructive sleep apnea.

CONCLUSION

The NoSAS score can accurately identify patients likely to have obstructive sleep apnea. Therefore, in the absence of polysomnography, one should use the NoSAS score to evaluate patients with suspected sleep apnea syndrome.

Increased de novo glutathione production enhances sexual dysfunctions in rats subjected to paradoxical sleep deprivation

OBJECTIVE

Poor quality of sexual life has been reported secondary to poor sleep or sleep deprivation. Paradoxical sleep is an integral part of the sleep-wakefulness physiology and prolonged paradoxical sleep deprivation (PSD) may even be fatal. The objective of this investigation was to determine if D-ribose-L-cysteine (RibCys) and zinc (Zn) administration can attenuate the effect of PSD on the sexual function of male rats.

METHODS

Following acclimatization, 25 male rats were randomly distributed into five groups of 5 rats each. The PSD, PSD+RibCys, PSD+Zn, PSD+RibCys+Zn, and Control groups were sleep-deprived only, sleep-deprived and given 100mg/kg body-weight of pure RibCys, sleep-deprived and given 10mg/kg body weight Zn, sleep-deprived and given a combination of 100mg/kg of RibCys and 10mg/kg of Zn, and given distilled water without sleep deprivation, respectively. PSD lasted for 20 hours per day for 14 days. Subsequently, the sexual behavioral study was carried out and the animals were sacrificed for biochemical assays.

RESULTS

Analyses of results show that for animals treated with RibCys or Zn, all sexual parameters such as mount frequency and latency, intromission frequency and latency and ejaculation frequency and latency were significantly improved compared with animals subjected to PSD only. This improvement correlates strongly with serum glutathione (GHS) levels.

CONCLUSION

In summary, riboceine increases circulating GHS, which leads to improved sexual function during sleep deprivation.

Economic evaluation of diagnostic sleep studies for obstructive sleep apnoea: a systematic review protocol

BACKGROUND

Obstructive sleep apnoea (OSA) is a significant public health problem affecting a large proportion of the population and is associated with adverse health consequences and a substantial economic burden. Despite the existence of effective treatment, undiagnosed OSA remains a challenge. The gold standard diagnostic tool is polysomnography (PSG), yet the test is expensive, labour intensive and time-consuming. Home-based, limited channel sleep study testing (levels 3 and 4) can advance and widen access to diagnostic services. This systematic review aims to summarise available evidence regarding the cost-effectiveness of limited channel tests compared to laboratory and home PSG in diagnosing OSA.

METHODS

Eligible studies will be identified using a comprehensive strategy across the following databases from inception onwards: MEDLINE, PsychINFO, SCOPUS, CINAHL, Cochrane Library, Emcare and Web of Science Core Collection and ProQuest databases. The search will include a full economic evaluation (i.e. cost-effectiveness, cost-utility, cost-benefit, cost-consequences and cost-minimisation analysis) that assesses limited channel tests and PSG. Two reviewers will screen, extract data for included studies and critically appraise the articles for bias and quality. Meta-analyses will be conducted if aggregation of outcomes can be performed. Qualitative synthesis using a dominance ranking matrix will be performed for heterogeneous data.

DISCUSSION

This systematic review protocol uses a rigorous, reproducible and transparent methodology and eligibility criteria to provide the current evidence relating to the clinical and economic impact of limited channel and full PSG OSA diagnostic tests. Evidence will be examined using standardised tools specific for economic evaluation studies.

TRIAL REGISTRATION

PROSPERO (CRD42020150130).

Effects of sleep deprivation on maternal behaviour in animal models: A systematic review and meta-analysis

Pregnancy is a period of numerous physical and emotional changes in women's lives, including alterations in sleep patterns and worsening of pre-existing sleep disturbances, which possibly lead to impaired postpartum maternal behaviour and mother-infant relationship. The effects of sleep deprivation during pregnancy in maternal behaviour have been evaluated in preclinical studies, but have provided inconsistent results. Thus, in the present study, we aimed to evaluate the effects of sleep deprivation during pregnancy on maternal behaviour of animals through a systematic review and meta-analyses. After a two-step selection process, six articles were included, all of them describing rat studies. The most frequently used method of sleep deprivation was rapid eye movement sleep restriction, using the multiple-platform method. Four meta-analyses were performed, none of them presenting significant impact of sleep deprivation on maternal behaviour, failing to reproduce the results observed in previous clinical studies. In conclusion, our results show a lack of translational applicability of animal models to evaluate the effects of sleep deprivation during pregnancy on maternal behaviour.

Independent effects of rapid eye movement sleep deprivation and exposure to environmental heat stress on aerobic performance and thermoregulatory responses in exercising rats

Evidence indicates that aerobic performance is degraded either by environmental heat stress or sleep deprivation. However, whether these conditions interact to produce more significant performance impairment deserves further investigation. Therefore, this study investigated the effects of experimental sleep deprivation (24 h or 96 h) on aerobic performance and thermoregulatory responses in rats exercised on a treadmill at different environmental conditions. Adult male Wistar rats were subjected to rapid eye movement sleep deprivation (RSD) using the modified multiple platform method and were then subjected to an incremental-speed exercise until they were fatigued. Treadmill running was performed in a temperate (24°C) or warm (31°C) environment, and the colonic temperature (an index of core body temperature; T_CORE) and the tail-skin temperature (T_SKIN; an index of cutaneous heat loss) were recorded. 24-h and 96-h RSD produced small magnitude reductions in aerobic performance (Cohen's d = 0.47-0.58) and minor changes in thermoregulation. Relative to control rats, sleep-deprived rats showed a higher T_CORE at the exercise initiation and a higher threshold for activating cutaneous heat loss, but unchanged T_CORE and T_SKIN at fatigue. Exercise at 31°C induced large reductions in performance (d = 0.82-1.29) and marked changes in thermoregulation, as evidenced by higher T_CORE and T_SKIN at fatigue, compared to exercise at 24°C. Interestingly, none of the effects induced by RSD were exacerbated by environmental heat stress and vice-versa, indicating that both conditions did not interact. We conclude that RSD and heat stress modulate aerobic performance and thermoregulatory responses by acting independently.

A meta-analysis: Does vitamin D play a promising role in sleep disorders?

BACKGROUND

Sleep disorders, one of the most common problems in the general population, have been related to a series of harmful health consequences. Vitamin D appears to be associated with sleep disorders. However, the difference in vitamin D levels between sleep disorder subjects and people without a sleep disorder is unclear. Simultaneously, the influence of vitamin D replenishment on sleep disorders remains controversial.

METHODS

PubMed, MEDLINE, Web of Science, and Cochrane Library were searched for literatures published until October 2019. Using a random effects model, a meta-analysis was conducted to calculate the standard mean difference to evaluate the difference in vitamin D concentrations between sleep disorder subjects and normal people and the efficacy of vitamin D supplementation on sleep disorders.

RESULTS

Our study found that the serum vitamin D levels in the sleep disorder subjects were lower than that in the normal people (SMD = -0.75 ng/ml, 95% CI = -0.93, -0.57 ng/ml). Moreover, the Pittsburgh Sleep Quality Index (PSQI)in the subjects with vitamin D supplementation was lower than that in the controls (SMD = -0.45, 95% CI = -0.76, -0.13).

CONCLUSIONS

Vitamin D could play a promising role in sleep disorders. More data are required to confirm the efficacy of vitamin D supplementation for improving sleep disorders.

Effects of sleep restriction during pregnancy on postpartum maternal behavior in female rats

Preclinical studies evaluating the effects of gestational sleep restriction on maternal behavior are needed in order to provide information on the background mechanisms underlying this relationship. In this study, 32 female 90 days-old Wistar-Hannover rats were distributed in two groups: Control group (CTRL - n = 13), not subjected to any manipulation during pregnancy; and sleep restriction group (SR - n = 19) - subjected to sleep restriction during the whole pregnancy (21 days). Maternal behavioral analysis was conducted from postpartum day 1 (PPD1) to PPD7, based on observational ethograms. On PPD11 the animals were subjected to the grooming analysis algorithm, followed by the elevated plus maze. Results from an ethogram-based analysis indicated a decrease in self-grooming among sleep-deprived rats (denoting reduced anxiety-like behavior), but no significant differences were found in maternal behavior (except for a slight increase in high arched-back nursing). Controlled analysis detected an impairment in high-arched back nursing in sleep-deprived animals. The grooming microstructure analysis showed an increased frequency of incorrect transitions among sleep restricted animals, indicating increased anxiety-like behavior. No significant differences were observed in the elevated-plus maze. In conclusion, sleep-restricted pregnant rats display an equivalent or slightly increased maternal behavior during the postpartum period, when compared to control animals.

Sleep debt induces skeletal muscle injuries in athletes: A promising hypothesis

Sleep is a physiological state and it is fundamental for physical and cognitive recovery of athletes. Due to strenuous training and competitions, athletes may present sleep complaints compromising good quality and quantity of sleep. Studies have related sleep debt to the occurrence of musculoskeletal injuries in athletes, but the mechanisms that can lead to this are not entirely clear. Studies involving animals and humans have shown that poor sleep quality can cause significant changes in hormones and cytokines. Demonstrating that this hormones changes lead to a decrease of testosterone and growth hormone levels and increased cortisol levels, important hormones in the process of protein synthesis and degradation. In athletes, the sport itself is a risk factor of injuries, and sleep debt may result in overtraining syndrome associated with inflammatory markers and ultimately to immune system dysfunction. Thus, we hypothesize that athletes who have sleep debt are more susceptible to musculoskeletal injuries due to increased catabolic pathway signaling, i.e. protein degradation and decreased anabolic pathway signaling, compromising muscle integrity. In this sense, we indicate the relationship between musculoskeletal injuries and sleep debt involving new targets for immunological signaling pathways that start the reduction of the muscle recovery process.

Autophagy Triggered by Oxidative Stress Appears to Be Mediated by the AKT/mTOR Signaling Pathway in the Liver of Sleep-Deprived Rats

Sleep deprivation adversely affects the digestive system. Multiple studies have suggested sleep deprivation and oxidative stress are closely related. Autophagy can be triggered by oxidative stress as a self-defense strategy to promote survival. In this study, we investigated the effects of sleep deprivation on liver functions, oxidative stress, and concomitant hepatocyte autophagy, as well as the associated pathways. Enzymatic and nonenzymatic biochemical markers in the serum were used to assess hepatic function and damage. To evaluate the occurrence of autophagy, expression of autophagy-related proteins was tested and autophagosomes were labeled. Additionally, methane dicarboxylic aldehyde (MDA), antioxidant enzymes, and the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway were analyzed using chemical methods and a Western blot. Serum alanine transaminase, aspartate aminotransferase, and alkaline phosphatase increased in sleep-deprived rats. Total protein and albumin abundance was also abnormal. Sleep deprivation induced histopathological changes in the liver. The superoxide dismutase level decreased significantly in the liver of sleep-deprived rats. In contrast, the MDA content increased in the sleep deprivation group. Moreover, the microtubule-associated protein 1 light chain 3 beta (LC3B) II/I ratio and Beclin I content increased considerably in the sleep-deprived rats, while p62 levels decreased. Sleep deprivation apparently inhibited the AKT/mTOR signaling pathway. We conclude that sleep deprivation can induce oxidative stress and ultimately cause liver injury. Autophagy triggered by oxidative stress appears to be mediated by the AKT/mTOR pathway and plays a role in relieving oxidative stress caused by sleep deprivation.

Neurobehavioural complications of sleep deprivation: Shedding light on the emerging role of neuroactive steroids

Sleep deprivation (SD) is associated with a broad spectrum of cognitive and behavioural complications, including emotional lability and enhanced stress reactivity, as well as deficits in executive functions, decision making and impulse control. These impairments, which have profound negative consequences on the health and productivity of many individuals, reflect alterations of the prefrontal cortex (PFC) and its connectivity with subcortical regions. However, the molecular underpinnings of these alterations remain elusive. Our group and others have begun examining how the neurobehavioural outcomes of SD may be influenced by neuroactive steroids, a family of molecules deeply implicated in sleep regulation and the stress response. These studies have revealed that, similar to other stressors, acute SD leads to increased synthesis of the neurosteroid allopregnanolone in the PFC. Whereas this up-regulation is likely aimed at counterbalancing the detrimental impact of oxidative stress induced by SD, the increase in prefrontal allopregnanolone levels contributes to deficits in sensorimotor gating and impulse control, signalling a functional impairment of PFC. This scenario suggests that the synthesis of neuroactive steroids during acute SD may be enacted as a neuroprotective response in the PFC; however, such compensation may in turn set off neurobehavioural complications by interfering with the corticolimbic connections responsible for executive functions and emotional regulation.

Protective effects of Hydrocotyle umbellata var. bonariensis Lam. (Araliaceae) on memory in sleep-impaired female mice

ETHNOPHARMACOLOGICAL RELEVANCE

Hydrocotyle umbellata var.bonariensis Lam. (Hb), popularly known in Brazil as acariçoba and outside Brazil Hb by a number of names including marsh-pennywort, and many-flower, has traditionally been used in Ayurvedic medicine in the retardation of aging (Rasayana effect).

AIM OF THE STUDY

The present study evaluated the effect of Hb treatment before and during paradoxical sleep deprivation (PSD) and sleep restriction (SR) on learning, memory, and acetylcholinesterase (AChE) brain activity.

MATERIAL AND METHODS

Adult Swiss nulliparous female mice were randomly distributed among the experimental groups. The treated groups received the aqueous solution of Hb leaves orally at concentrations of 500 and 1.000 mg/kg. PSD and SR were induced by the multiple platform method, in which the animals remained for 3-days in PSD or 15-days in SR for 22 h per day. The collection of the vaginal epithelium occurred daily to determine the estrous cycle. Body mass gain was determined. The animals were submitted to the passive avoidance test and were then euthanized for the collection of brain tissue and the determination of cerebral cholinesterase activity.

RESULTS

The aqueous solution of Hb was associated with a significant reduction in cholinesterase activity at both doses in the SR model, and at the dose of 1.000 mg/kg in the PSD model. Regarding the learning and memory test, the PSD group treated with 1.000 mg/kg presented significant improvement, whereas in the SR experiment none of the treated-groups showed any improvement in learning and memory. In the analysis of SR/PSD interference and/or Hb treatment on the estrous cycle, it was possible to observe that the treatment acted as a protector in the SR group, maintaining a normal cycle.

CONCLUSIONS

The analyses showed that Hb was safe to use during periods of SR or PSD, acting as an adaptogen for these situations, in addition to being able to reduce cholinesterase activity, which suggests its neuroprotective action. In relation to the estrous cycle, Hb can act as a protector in SR situations.

Effects of lithium and valproate on behavioral parameters and neurotrophic factor levels in an animal model of mania induced by paradoxical sleep deprivation

The present study aimed to evaluate the effects of treatment with lithium (Li) and valproate (VPA) on behaviors and brain BDNF, NGF, NT-3, NT-4 and GDNF levels in mice submitted to paradoxical sleep deprivation (PSD), which induces an animal model of mania. Male C57BL/6J mice received an intraperitoneal (i.p.) injection of saline solution (NaCl 0.09%, 1 ml/kg), Li (47.3 mg/kg, 1 ml/kg) or VPA (200 mg/kg, 1 ml/kg) once a day for seven days. Animals were randomly distributed into six groups (n = 10 per group): (1) Control + Sal; (2) Control + Li; (3) Control + VPA; (4) PSD + Sal; (5) PSD + Li; or (6) PSD + VPA. Animals were submitted to 36 h of PSD, and then, they were submitted to the open field test. The frontal cortex and hippocampus were dissected from the brain. The manic-like behaviors in the mice were analyzed. Treatment with Li and VPA reversed the behavioral alterations induced by PSD. PSD decreased BDNF, NGF, and GDNF levels in the frontal cortex and hippocampus of mice. The administration of Li and VPA protected the brain against the damage induced by PSD. However, PSD and the administration of Li and VPA did not affect the levels of NT-3 and NT-4 in either brain structure evaluated. In conclusion, the PSD protocol induced manic-like behavior in rats and induced alterations in neurotrophic factor levels. It seems that neurotrophic factors and sleep are essential targets to treat BD.

Sleep deprivation reduces the recovery of muscle injury induced by high-intensity exercise in a mouse model

Sleep is crucial to improve athlete performance and their circadian rhythm, but sleep patterns may be disturbed because athletes participate in several competitions. In addition, intensive training programs can cause muscle pain and psychological stress in athletes, resulting in a lack of sleep. Sleep also plays a critical role in the recovery of muscle injury induced by exercise. The current study evaluated the effect of sleep deprivation on the recovery of muscle injury induced by high-intensity exercise in a mouse model. In this study, 28 mice were randomly assigned to four groups (N = 7): control (Control), exercise (EX), sleep deprivation (SD), and sleep deprivation with exercise (EX+SD). The mice from the EX and EX+SD groups were subjected to high-intensity swimming. The results showed that 72-h sleep deprivation increased food intake and reduced body weight. However, the manipulation of 8-week exercise and/or 72-h sleep deprivation did not have any effect in the elevated plus maze task and tail suspension test. Interestingly, the EX+SD group exhibited improved memory performance in the Morris water maze and impaired motor activity in the open field test. According to the TNF-α level and aspartate aminotransferase (AST), and creatine phosphokinase (CK) activities, only the EX+SD group exhibited muscle impairment. Overall, high-intensity exercise may cause muscle injury, and adequate sleep can recover muscle damage. However, sleep deprivation reduces protein synthesis, which decreases the ability to restore muscle damage and aggravates the harmful effect of high-intensity exercise.

The Association between Sleep Duration and Dizziness in Korean Women: The Korea National Health and Nutrition Examination Survey

BACKGROUND

The aim of this study was to investigate the association between sleep duration and dizziness in a representative Korean population.

METHODS

We analyzed data from the Korea National Health and Nutrition Examination Surveys (2010-2012). A total of 12,499 adults who completed otolaryngologic examinations were evaluated.

RESULTS

Both men and women with severely short sleep duration (≤ 5 hours) and severely long sleep duration (≥ 9 hours) tended to have higher dizziness prevalence. However, the adjusted odds ratio (OR) for sleep duration was only significant in women with dizziness after adjusting for confounders. Compared to that in an optimal sleep group (6-8 hr/day), the OR (95% confidence interval) for dizziness prevalence after adjusting for age and health behaviors (body mass index, smoking habit, alcohol consumption, level of exercise, metabolic syndrome, and tinnitus) was 1.473 (1.194-1.818) for the severely short sleep group (≤ 5 hr/day) and 1.472 (1.078-2.009) for the severely long sleep group (≥ 9 hr/day) only in women.

CONCLUSION

In the Korean population, dizziness was associated with shorter or longer sleep durations only among women. Further epidemiologic and experimental studies are necessary to clarify the impact of dizziness on sleep disorders.

Short-term sleep fragmentation enhances anxiety-related behavior: The role of hormonal alterations

Introduction

The neuroendocrine background of acute sleep fragmentation in obstructive sleep apnea and sleep fragmentation involvement in psychiatric comorbidities, common in these patients, are still largely unknown. The aim of this study was to determine the effects of short-term experimental sleep fragmentation on anxiety -like behavior and hormonal status in rats.

Methods

Male rats were adapted to treadmill (ON and OFF mode with belt speed set on 0.02m/s and 0.00m/s) and randomized to: 1) treadmill control (TC, only OFF mode); 2) motion, activity control (AC, 10min ON and 30min OFF mode) and 3) sleep fragmentation (SF, 30s ON and 90s OFF mode) group. Six hours later, the animals were tested in the open field, elevated plus maze and light/dark test (n = 8/group). Testosterone, estradiol, progesterone and corticosterone were determined in separate animal cohort immediately upon sleep fragmentation (n = 6/group).

Results

SF rats showed decreased rearings number, decreased time spent in the central area and increased thigmotaxic index compared to TC and AC rats in the open field test. Similarly, increased anxiety upon sleep fragmentation was observed in the elevated plus maze and the light/dark test. Significantly lower testosterone, estradiol and progesterone levels were determined in SF in comparison to AC and TC groups, while there was no significant difference in the levels of corticosterone.

Conclusion

Short term sleep fragmentation enhances anxiety-related behavior in rats, which could be partly mediated by the observed hormonal changes presented in the current study in form of testosterone, estradiol and progesterone depletion.

Feasibility of Single Channel Oximetry for Mass Screening of Obstructive Sleep Apnea

BACKGROUND

The growing awareness for the high prevalence of obstructive sleep apnea (OSA) coupled with the dramatic proportion of undiagnosed individuals motivates the elaboration of a simple but accurate screening test. This study assesses, for the first time, the performance of oximetry combined with demographic information as a screening tool for identifying OSA in a representative (i.e. non-referred) population sample.

METHODS

A polysomnography (PSG) clinical database of 887 individuals from a representative population sample of São Paulo's city (Brazil) was used. Using features derived from the oxygen saturation signal during sleep periods and demographic information, a logistic regression model (termed OxyDOSA) was trained to distinguish between non-OSA and OSA individuals (mild, moderate, and severe). The OxyDOSA model performance was assessed against the PSG-based diagnosis of OSA (AASM 2017) and compared to the NoSAS and STOP-BANG questionnaires.

FINDINGS

The OxyDOSA model had mean AUROC = 0.94 ± 0.02, Se = 0.87 ± 0.04 and Sp = 0.85 ± 0.03. In particular, it did not miss any of the 75 severe OSA individuals. In comparison, the NoSAS questionnaire had AUROC = 0.83 ± 0.03, and missed 23/75 severe OSA individuals. The STOP-BANG had AUROC = 0.77 ± 0.04 and missed 14/75 severe OSA individuals.

INTERPRETATION

We provide strong evidence on a representative population sample that oximetry biomarkers combined with few demographic information, the OxyDOSA model, is an effective screening tool for OSA. Our results suggest that sleep questionnaires should be used with caution for OSA screening as they fail to identify many moderate and even some severe cases. The OxyDOSA model will need to be further validated on data recorded using overnight portable oximetry.

Naps and exercise: reinforcing a range of benefits for elderly health

According to the United Nations, in 2017, people aged 60 or over in the world, comprised 13 per cent of the global population. It is a fact that elderly people are keeping a health lifestyle, such as practicing physical exercises and avoiding excessive dosages of medications. However, this population is also more prone to have injuries while practicing exercises. Sleep architecture is physiologically different among elderly, and naps can be very beneficial to improve their mental and physical health. Thus, in this article, we encourage health professionals to recommend regular naps to this population, which could lead to an improve in their well-being and quality of life.