The UPR and the Anti-oxidant Response: Relevance to Sleep and Sleep Loss

Oxidative stress has been linked to various physiological and pathological processes such as aging and neurological disorders. Recent evidence has now implicated a role for oxidative stress in sleep and sleep loss. Studies suggest that wakefulness results in an oxidative burden and sleep provides a protective mechanism against these harmful effects. Prolonged wakefulness/sleep deprivation activates an adaptive stress pathway termed the unfolded protein response (UPR), which temporarily guards against the deleterious consequences of reactive oxygen species. The UPR affects the function of the endoplasmic reticulum, which is the site for integral and secretory membrane processing and folding. Several downstream effectors of the UPR operate in an antioxidant capacity to reduce the load of these toxic species; a process that may be important in delaying the progression of neurodegenerative diseases. This review will highlight the molecular components of the UPR that ameliorate the accumulation of oxidative stress and may therefore provide potential therapeutic targets.     

Energy Stores Are Not Altered by Long-Term Partial Sleep Deprivation in Drosophila melanogaster

Recent human studies reveal a widespread association between short sleep and obesity. Two hypotheses, which are not mutually exclusive, might explain this association. First, genetic factors that reduce endogenous sleep times might also impact energy stores, an assertion that we confirmed in a previous study. Second, metabolism may be altered by chronic partial sleep deprivation. Here we address the second assertion by measuring the impact of long-term partial sleep deprivation on energy stores using Drosophila as a model. We subjected flies to long-term partial sleep deprivation via two different methods: a mechanical stimulus and a light stimulus. We then measured whole-body triglycerides and glycogen, two important sources of energy for the fly, and compared them to un-stimulated controls. We also measured changes in energy stores in response to a random circadian clock shift. Sex and line-dependent alterations in glycogen and/or triglyceride levels occurred in response to the circadian clock shift and in flies subjected to a single night of sleep deprivation using light. Thus, consistent with previous studies, our findings suggest that acute sleep loss and changes to the circadian clock can alter metabolism. Significant changes in energy stores were also observed when flies were subjected to chronic sleep loss via the mechanical stimulus, although not the light stimulus. Interestingly, mechanical stimulation resulted in the same change in energy stores even when it was not associated with sleep deprivation, suggesting that the changes are caused by stress rather than sleep loss. These findings emphasize the importance of taking stress into account when evaluating the relationship between sleep loss and metabolism.     

Compensatory Reserves of the Human Body and Population Health under Conditions of Exposure to Chronic Anthropogenic Factors and Prolonged Psychoemotional Stress

Long-term exposure to adverse factors of various origin and intensity is expected to cause a significant decrease in the compensatory reserves and adaptive capacity of the human body. These changes deteriorate the population health status in general. A quantitative method of evaluation of the decrease in the compensatory reserves and adaptive capacity, as well as the resistance to chronic exposure to extreme factors of various origin and intensity, was developed. This method is based on the concept of stress and programmable nonspecific physiological reactions of the human body put forward by H. Selye. Model analytical curves of the time-related decrease in the volume of compensatory reserves and the increase in the probability of development of adaptive disorders and failure of the adaptation process were calculated for the cases of long-term exposure to various stressors (the factors were applied individually or in combination). This method allowed the levels of population health risk induced by various factors to be compared to each other. This is of particular importance under conditions of the existing trend toward an increase in the intensity of anthropogenic stress factors against the background of long-term psychoemotional stress. Statistical data on changes in the rates of morbidity and mortality and the life expectancy of Russian people for the period 1960–2000 were analyzed. The levels of risk of the negative impact on population health induced by various stress factors (radiation, chemical environmental pollution, and long-term psychoemotional stress) were compared to each other.     

Sleep and nesting behavior in primates: A review

Sleep is a universal behavior in vertebrate and invertebrate animals, suggesting it originated in the very first life forms. Given the vital function of sleep, sleeping patterns and sleep architecture follow dynamic and adaptive processes reflecting trade-offs to different selective pressures. Here, we review responses in sleep and sleep-related behavior to environmental constraints across primate species, focusing on the role of great ape nest building in hominid evolution. We summarize and synthesize major hypotheses explaining the proximate and ultimate functions of great ape nest building across all species and subspecies; we draw on 46 original studies published between 2000 and 2017. In addition, we integrate the most recent data brought together by researchers from a complementary range of disciplines in the frame of the symposium “Burning the midnight oil” held at the 26th Congress of the International Primatological Society, Chicago, August 2016, as well as some additional contributors, each of which is included as a “stand-alone” article in this “Primate Sleep” symposium set. In doing so, we present crucial factors to be considered in describing scenarios of human sleep evolution: (a) the implications of nest construction for sleep quality and cognition; (b) the tree-to-ground transition in early hominids; (c) the peculiarities of human sleep. We propose bridging disciplines such as neurobiology, endocrinology, medicine, and evolutionary ecology, so that future research may disentangle the major functions of sleep in human and nonhuman primates, namely its role in energy allocation, health, and cognition.     

维持性血液透析患者睡眠质量的影响因素及与氧化应激水平、生活质量和疲乏状况的关系研究

摘要 目的：分析调查维持性血液透析（MHD）患者睡眠质量的影响因素,并分析其与生活质量、氧化应激水平和疲乏状况的关系。方法：研究对象选取自2019年8月~2021年5月在首都医科大学附属北京朝阳医院血液透析室长期规律行MHD治疗的终末期肾脏病患者150例,收集患者的临床资料,采用匹兹堡睡眠指数（PSQI）量表评定睡眠质量。采用修订版Pieper疲劳量表（RPFS）评估所有患者的疲乏程度。采用肾脏病生活质量量表（KDQOL-SF）评估患者生活质量。分析MHD患者睡眠质量的影响因素,并分析其与氧化应激水平、生活质量和疲乏状况的关系。结果：150例MHD患者中有114例PSQI评分>5分,本血液透析室MHD患者睡眠障碍发生率为76.00% (114/150)。根据是否发生睡眠障碍将患者分为睡眠障碍组（n=114）和无睡眠障碍组（n=36）。单因素分析结果显示睡眠障碍组、无睡眠障碍在年龄、透析时间、血红蛋白（Hb）、血清甲状旁腺激素（iPTH）、透析治疗效率标准（Kt/V）、血钙方面组间对比有差异（P<0.05）。透析时间、年龄、Hb、iPTH、Kt/V均是MHD患者睡眠质量的影响因素（P<0.05）。睡眠障碍组的一般健康状况、肾病相关、总分均低于无睡眠障碍组（P<0.05）。睡眠障碍组的疲乏评分高于无睡眠障碍组（P<0.05）。睡眠障碍组的丙二醛（MDA）高于无睡眠障碍组,超氧物歧化酶（SOD）、人谷胱甘肽-过氧化物酶（GSH-Px）低于无睡眠障碍组（P<0.05）。结论：透析时间、年龄、Hb、iPTH、Kt/V均是MHD患者睡眠质量的影响因素,且睡眠质量变差会加重MHD患者疲乏程度,加重氧化应激反应,降低患者的生活质量。     

Physiological and pathophysiological roles of adenosine

Adenosine is a candidate sleep substance. It can be both a distress signal of importance in pathology and a physiological regulator. Key factors in determining which of these possibilities pertain are: (i) the number of receptors expressed, and (ii) the mechanisms that establish extracellular adenosine levels. The roles of adenosine are studied by means of antagonists and/or animals (mostly mice) with targeted deletions of receptors or enzymes involved in adenosine metabolism. Whereas adaptive changes in the genetically modified mice can occur for the physiologically important effects, such adaptive changes are less likely to occur in situations where adenosine acts as a distress signal. The relevance to sleep will be covered only in general terms in this review and will be covered in other contributions to this volume.

     

Effect of sleep environment of preschool children on children’s sleep problems and mothers’ mental health

Sleep and Biological Rhythms - We evaluated the sleep environment factors that influence children’s sleep, and the relationship between co-sleeping and parenting stress and parents’...     

Sleep intensity and the evolution of human cognition

Over the past four decades, scientists have made substantial progress in understanding the evolution of sleep patterns across the Tree of Life. 1 , 2 Remarkably, the specifics of sleep along the human lineage have been slow to emerge. This is surprising, given our unique mental and behavioral capacity and the importance of sleep for individual cognitive performance. 3 - 5 One view is that our species' sleep architecture is in accord with patterns documented in other mammals. 6 We promote an alternative view, that human sleep is highly derived relative to that of other primates. Based on new and existing evidence, we specifically propose that humans are more efficient in their sleep patterns than are other primates, and that human sleep is shorter, deeper, and exhibits a higher proportion of REM than expected. Thus, we propose the sleep intensity hypothesis: Early humans experienced selective pressure to fulfill sleep needs in the shortest time possible. Several factors likely served as selective pressures for more efficient sleep, including increased predation risk in terrestrial environments, threats from intergroup conflict, and benefits arising from increased social interaction. Less sleep would enable longer active periods in which to acquire and transmit new skills and knowledge, while deeper sleep may be critical for the consolidation of those skills, leading to enhanced cognitive abilities in early humans.     

Evolution and sudden infant death syndrome (SIDS)

This paper and its subsequent parts (Part II and Part III) build on an earlier publication (McKenna 1986). They suggest that important clinical data on the relationship between infantile constitutional deficits and microenvironmental factors relevant to SIDS can be acquired by examining the physiological regulatory effects (well documented among nonhuman primates) that parents assert on their infants when they sleep together. I attempt to show why access to parental sensory cues (movement, touch, smell, sound) that induce arousals in infants while they sleep could possibly help one of many different subclasses of infants either to override certain kinds of sleep-induced breathing control errors suspected to be involved in SIDS or to avoid them altogether. I do not suggest that solitary nocturnal sleep “causes” SIDS, that all parents should sleep with their infants, or that traditional SIDS research strategies should be abandoned. However, using evolutionary data, I do suggest that an adaptive fit exists between parent-infant sleep contact and the natural physiological vulnerabilities of the neurologically immature human infant, whose breathing system is more complex than that of other mammals owing to its speech-breathing abilities. This “fit” is best understood, it is argued, in terms of the 4–5 million years of human evolution in which parent-infant contact was almost certainly continuous during at least the first year of an infant’s life. Thus, to dismiss the idea that solitary sleep has no physiological consequences for infants does not accord with scientific facts. James J. McKenna is Associate Professor of Anthropology and Chair of the Department of Sociology and Anthropology at Pomona College. He also has an appointment as an Adjunct Clinical Assistant Professor in the Departments of Pediatrics, Child Psychiatry, and Human Behavior at the University of California, Irvine, School of Medicine. His primary research interests and many of his publications concern aspects of primate parenting and infant development among both human and nonhuman primates. For the past seven years he has been investigating from an anthropological perspective possible environmental correlates of the sudden infant death syndrome (SIDS) and has just finished a preliminary study on the physiological correlates of human parent-infant co-sleeping. His earlier monograph on the subject (cited in this paper) has received much international attention. He and his colleagues (Mosko and Dungy) are the first to have used standard polysomnographic techniques to document simultaneously human parent-infant co-sleeping. He has won three awards for distinguished teaching at Pomona College.     

General Stress in Anthropological Fieldwork

Human stress reactions are responses to physical, biotic, and sociocultural stimuli that lead to appraisal of the need for adaptive activity. Commonly used measures of stress in anthropology, such as questionnaires, are subjective in nature and inappropriate for cross-cultural comparisons. Physiological measures of stress, such as urinary levels of catecholamines and corticosteroids, are applicable for these comparisons and may have wide utility in anthropological fieldwork, particularly for: studies of culture change, identification of highly stressed groups or individuals within groups, and observations of temporal patterns of stress in human populations . [stress, biocultural anthropology, adaptation, physiological anthropology, human ecology]     

Effects of thermal environment on sleep and circadian rhythm

ABSTRACT: The thermal environment is one of the most important factors that can affect human sleep. The stereotypical effects of heat or cold exposure are increased wakefulness and decreased rapid eye movement sleep and slow wave sleep. These effects of the thermal environment on sleep stages are strongly linked to thermoregulation, which affects the mechanism regulating sleep. The effects on sleep stages also differ depending on the use of bedding and/or clothing. In semi-nude subjects, sleep stages are more affected by cold exposure than heat exposure. In real-life situations where bedding and clothing are used, heat exposure increases wakefulness and decreases slow wave sleep and rapid eye movement sleep. Humid heat exposure further increases thermal load during sleep and affects sleep stages and thermoregulation. On the other hand, cold exposure does not affect sleep stages, though the use of beddings and clothing during sleep is critical in supporting thermoregulation and sleep in cold exposure. However, cold exposure affects cardiac autonomic response during sleep without affecting sleep stages and subjective sensations. These results indicate that the impact of cold exposure may be greater than that of heat exposure in real-life situations; thus, further studies are warranted that consider the effect of cold exposure on sleep and other physiological parameters.     

The effect of memorization processes on the structural organization of natural human sleep

The effect of sleep on learning was investigated, comparing results of memorizing and reproduction of an unknown text before and after subsequent sleep, with a detailed analysis of sleep patterns. Psychological tests excluded the possibility of emotional and stress factors. Presleep learning did not influence mean values of such sleep parameters as total sleep time or duration of different sleep stages. The main finding ot the present experiment was a redistribution of stage REM during nocturnal sleep following learning--its increase in the second sleep cycle with a corresponding decrease toward the end of night. Also, individual difficulties in learning were inversely related to REM latency. Changes in sleep patterns after learning didn't influence the total number of sleep cycles. It is suggested that the REM phase of sleep might be involved in the processing of information acquired during wakefulness.     

Correlates of Self-Reported Sleep Duration in Middle-Aged and Elderly Koreans: from the Health Examinees Study

Though various factors related to fluctuations in sleep duration have been identified, information remains limited regarding the correlates of short and long sleep duration among the Korean population. Thus, we investigated characteristics that could be associated with short and/or long sleep duration among middle-aged and elderly Koreans. A total of 84,094 subjects (27,717 men and 56,377 women) who participated in the Health Examinees Study were analyzed by using multinomial logistic regression models. To evaluate whether sociodemographic factors, lifestyle factors, psychological conditions, anthropometry results, and health conditions were associated with short and/or long sleep duration, odds ratios (ORs) and 95% confidence intervals (CIs) were estimated with sleep duration of 6–7 hours as the reference group, accounting for putative covariates. Regardless of sexual differences, we found that adverse behaviors and lifestyle factors including low educational attainment, unemployment, being unmarried, current smoking status, lack of exercise, having irregular meals, poor psychosocial well-being, frequent stress events, and poor self-rated health were significantly associated with abnormal sleep duration. Similarly, diabetes mellitus and depression showed positive associations with abnormal sleep duration in both men and women. Our findings suggest that low sociodemographic characteristics, adverse lifestyle factors, poor psychological conditions, and certain disease morbidities could be associated with abnormal sleep duration in middle-aged and elderly Koreans.     

Night sleep structural alteration as a function of individual strategy of adapting to 520-day isolation

The purpose of the study was to establish a relationship between trends in sleep alteration and individual adaptation to stress factors in the 520-day isolation study. Psychological evaluations using a battery of motivation tests, Sobchik’s modification of the Luscher personality test, and Mirror coordinograph made it possible to differentiate groups responding to the stress according to the pattern “control” (G-1) or “search” (G-2) manifested in individual styles of behavior and operator’s activity. The two groups exhibited different dynamics of the night sleep structure. Difficulties with falling asleep in G-1 arose on the eve of “landing onto Mars” and end of the experiment, whereas in G-2 they were evident prior to the end only. In addition, the micro- and segmental sleep structures were more stable in G-1, suggesting the integrity of somnogenic mechanisms despite difficult sleep initiation.     

Sleep after vaccination boosts immunological memory

Sleep regulates immune functions. We asked whether sleep can influence immunological memory formation. Twenty-seven healthy men were vaccinated against hepatitis A three times, at weeks 0, 8, and 16 with conditions of sleep versus wakefulness in the following night. Sleep was recorded polysomnographically, and hormone levels were assessed throughout the night. Vaccination-induced Th cell and Ab responses were repeatedly monitored for 1 y. Compared with the wake condition, sleep after vaccination doubled the frequency of Ag-specific Th cells and increased the fraction of Th1 cytokine-producing cells in this population. Moreover, sleep markedly increased Ag-specific IgG1. The effects were followed up for 1 y and were associated with high sleep slow-wave activity during the postvaccination night as well as with accompanying levels of immunoregulatory hormones (i.e., increased growth hormone and prolactin but decreased cortisol release). Our findings provide novel evidence that sleep promotes human Th1 immune responses, implicating a critical role for slow-wave sleep in this process. The proinflammatory milieu induced during this sleep stage apparently acts as adjuvant that facilitates the transfer of antigenic information from APCs to Ag-specific Th cells. Like the nervous system, the immune system takes advantage of the offline conditions during sleep to foster adaptive immune responses resulting in improved immunological memory.