The role of insufficient sleep and circadian misalignment in obesity

Decoding the nexus: branched-chain amino acids and their connection with sleep, circadian rhythms, and cardiometabolic health

The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and, either directly or indirectly, overall body health, encompassing metabolic and cardiovascular well-being. Given the heightened metabolic activity of the brain, there exists a considerable demand for nutrients in comparison to other organs. Among these, the branched-chain amino acids, comprising leucine, isoleucine, and valine, display distinctive significance, from their contribution to protein structure to their involvement in overall metabolism, especially in cerebral processes. Among the first amino acids that are released into circulation post-food intake, branched-chain amino acids assume a pivotal role in the regulation of protein synthesis, modulating insulin secretion and the amino acid sensing pathway of target of rapamycin. Branched-chain amino acids are key players in influencing the brain's uptake of monoamine precursors, competing for a shared transporter. Beyond their involvement in protein synthesis, these amino acids contribute to the metabolic cycles of γ-aminobutyric acid and glutamate, as well as energy metabolism. Notably, they impact GABAergic neurons and the excitation/inhibition balance. The rhythmicity of branched-chain amino acids in plasma concentrations, observed over a 24-hour cycle and conserved in rodent models, is under circadian clock control. The mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully understood. Disturbed sleep, obesity, diabetes, and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory dynamics. The mechanisms driving these effects are currently the focal point of ongoing research efforts, since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these pathologies. In this context, the Drosophila model, though underutilized, holds promise in shedding new light on these mechanisms. Initial findings indicate its potential to introduce novel concepts, particularly in elucidating the intricate connections between the circadian clock, sleep/wake, and metabolism. Consequently, the use and transport of branched-chain amino acids emerge as critical components and orchestrators in the web of interactions across multiple organs throughout the sleep/wake cycle. They could represent one of the so far elusive mechanisms connecting sleep patterns to metabolic and cardiovascular health, paving the way for potential therapeutic interventions.

Depressive symptoms mediate the association between dietary inflammatory index and sleep: A cross-sectional study of NHANES 2005-2014

BACKGROUND

Sleep pattern (sleep duration, trouble sleeping, sleep disorder) is associated with both energy density dietary inflammatory index (EDII) and depression. However, whether depression mediates the EDII-sleep pattern relationship is unclear.

METHODS

14,305 participants from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2014 were included in this study. Weighted multivariable logistic regression and mediated effect analysis were conducted to analyze the associations between EDII, depression and sleep pattern.

RESULTS

In the regression model with full confounding variables adjusted, the OR (95 % CI) for the association between EDII and sleep pattern was 2.11 (1.44, 3.08). Similarly, comparing the highest to the lowest EDII scores, the association with depression yielded an identical OR of 2.62 (1.89, 3.64). Mediation models showed depressive symptoms mediated 24.06 % of the EDII-sleep pattern link. Analysis by sleep pattern subtypes found depressive symptoms mediated 18.22 % for sleep duration, 30.53 % for sleep disorder (both with substantial direct EDII effects), and 93.73 % for trouble sleeping, where EDII's direct impact was not considerable.

CONCLUSION

Positive association of EDII with unhealthy sleep pattern is partly mediated by depression, and anti-inflammatory diet could be beneficial.

The Cross-Sectional and Longitudinal Association Between 24-Hour Movement Behavior Compositions With Body Mass Index, Waist Circumference, and Internalizing and Externalizing Symptoms in 6-Year-Old Children

BACKGROUND

Few studies have examined the association between 24-hour movement behaviors and health in children in their first 2 years of primary school. This study aimed to examine how 24-hour movement behavior compositions at age 6 were related to body mass index (BMI), waist circumference, and internalizing and externalizing symptoms at ages 6 and 10.

METHODS

A subsample of 361 children from the HealthNuts cohort study with valid accelerometer data was included in the cross-sectional analysis. Of these, 279 had longitudinal data for social-emotional outcomes and 113 had longitudinal anthropometric data. Children's 24-hour movement behaviors (ie, sleep, sedentary time, light-intensity physical activity, and moderate- to vigorous-intensity physical activity [MVPA]) were assessed over 8 days using accelerometery and activity logs. BMI z score and waist circumference were assessed using standardized protocols, and parents reported on their child's internalizing and externalizing behaviors. Cross-sectional and longitudinal associations were estimated using compositional data analysis and compositional isotemporal substitution analysis.

RESULTS

Overall, 24-hour movement behaviors were significantly related to internalizing symptoms cross-sectionally and longitudinally and BMI z-score cross-sectionally. Results from compositional isotemporal substitution models indicated that replacing sedentary time or light-intensity physical activity with MVPA was associated with fewer internalizing symptoms at ages 6 and 10. Replacing time spent sedentary and in light-intensity physical activity or MVPA with sleep was associated with lower BMI z score at age 6.

CONCLUSION

Spending more time in MVPA relative to other movement behaviors is associated with fewer internalizing symptoms. In additional, spending more time sleeping is associated with lower BMI z score and waist circumference in children.

Raptin, a sleep-induced hypothalamic hormone, suppresses appetite and obesity

Sleep deficiency is associated with obesity, but the mechanisms underlying this connection remain unclear. Here, we identify a sleep-inducible hypothalamic protein hormone in humans and mice that suppresses obesity. This hormone is cleaved from reticulocalbin-2 (RCN2), and we name it Raptin. Raptin release is timed by the circuit from vasopressin-expressing neurons in the suprachiasmatic nucleus to RCN2-positive neurons in the paraventricular nucleus. Raptin levels peak during sleep, which is blunted by sleep deficiency. Raptin binds to glutamate metabotropic receptor 3 (GRM3) in neurons of the hypothalamus and stomach to inhibit appetite and gastric emptying, respectively. Raptin-GRM3 signaling mediates anorexigenic effects via PI3K-AKT signaling. Of note, we verify the connections between deficiencies in the sleeping state, impaired Raptin release, and obesity in patients with sleep deficiency. Moreover, humans carrying an RCN2 nonsense variant present with night eating syndrome and obesity. These data define a unique hormone that suppresses food intake and prevents obesity.

Sex Differences in Circadian Timing and Biological Night in Adolescents

Circadian rhythms, intrinsic 24-h cycles that drive rhythmic changes in behavior and physiology, are important for normal physiology and health. Previous work in adults has identified sex differences in circadian rhythms of melatonin, temperature, and the intrinsic period of the human circadian timing system. However, less is known about sex differences in circadian rhythms at other developmental stages. To address this gap, we considered a secondary analysis of sleep and circadian data from two studies involving adolescent participants during the academic year: (n = 32, 15 females). We collected 1 week of in-home actigraphy data to calculate sleep-wake parameters and in-laboratory salivary melatonin data collection in dim-light conditions was used to compute dim-light melatonin onset (DLMO) and offset (DLMOff) using a threshold of 4 pg/mL. We found that DLMO was an average of 96 min earlier, the time between DLMO and bedtime was an average of 56 min greater, and the biological night (time between DLMO and DLMOff) was 60 min longer in females compared to males, even though bedtimes and waketimes were not statistically different between the groups. In addition, after accounting for differences in bedtime, sex was still a significant predictor of DLMO. Conversely, no evidence was found indicating a difference in DLMOff or the phase angle between DLMOff and waketime by sex. These findings suggest that sex differences in circadian rhythms are present in adolescents and may have implications for circadian health during this important developmental period.

The association of activity patterns on female reproductive diseases: a prospective cohort study of UK biobank

OBJECTIVE

Little is known about the role of timing of physical activity in female reproductive disorders. These disorders include polycystic ovary syndrome (PCOS), heavy menstrual bleeding (HMB), endometriosis, infertility, and pregnancy-related disorders. This study aims to investigate the associations of activity patterns with female reproductive diseases.

METHODS

A total of 49,540 female participants from the UK Biobank with valid accelerometer data were enrolled at baseline. Activity patterns were defined based on the timing of moderate-to-vigorous intensity physical activity (MVPA) throughout the day. Participants were categorized into four groups according to the timing of their MVPA: "morning, evening, mixed, midday-afternoon", with the midday-afternoon group serving as the reference. Cox proportional hazards models were utilized to evaluate the association between activity patterns and female reproductive diseases.

RESULTS

During a median follow-up of 12.6 years, a total of 1044 cases of female reproductive diseases were documented. After adjustment for potential confounders, compared to women with midday-afternoon exercise, women with morning exercise and mixed-timing exercise were associated with lower risks for female reproductive diseases (HRmorning=0.81, 95% CI: 0.67-0.98; HRmixed=0.79, 95% CI: 0.69-0.91, P-trend < 0.05). Moreover, morning exercise and mixed-timing exercise had lower risks of PCOS (HRmorning=0.38, 95% CI: 0.15-0.97; HRmixed=0.27, 95% CI: 0.13-0.57, P-trend<0.001), and mixed-timing exercise was associated with a lower risk for HMB (HRmixed=0.81, 95% CI: 0.70-0.95, P-trend < 0.05), compared with the reference group.

CONCLUSIONS

Compared with midday-afternoon group, morning and mixed MVPA timing groups, but not evening group, were associated with decreased risks for female reproductive diseases and PCOS. In addition, we found that women with mixed MVPA timing exercise had a lower risk of HMB, compared with the reference group.

Impact of nocturnal road traffic noise and annoyance on self-reported insomnia symptoms: policy intervention in noise-polluted environments

Chronic exposure to traffic noise is associated with increased stress and sleep disruptions. Research on the health consequences of environmental noise, specifically traffic noise, has primarily been conducted in high-income countries (HICs), which have guided the development of noise regulations. The relevance of these findings to policy frameworks in low- and middle-income countries (LMICs) remains uncertain. To investigate the relationship between road traffic noise exposure and annoyance on insomnia symptoms, a questionnaire survey was administered to 5408 randomly selected participants residing in Srinagar, India. Sleep quality was assessed using a standardized sleep disturbance score, along with self-reported annoyance levels related to road traffic noise at the participants' residences. Nighttime road traffic noise was modeled using Sound PLAN 8.2 software to generate noise contour maps, enabling the spatial evaluation of noise levels along roadways near residential areas. A total of 79.3% of the 5408 respondents were exposed to noise levels exceeding 45 Lnight dB(A). Statistically significant associations were observed between traffic noise exposure and all insomnia symptoms, with difficulty falling asleep showing the strongest association (OR = 1.53; 95% CI = 1.12-2.09) within the study sample. Compared to males, females exhibited higher insomnia symptoms (OR = 1.68; 95% CI = 1.35-2.08). The results indicated that insomnia was strongly correlated with an increased odds of traffic noise annoyance (OR = 2.39; 95% CI = 1.73-3.76) (p = 0.029). Finally, this study advocates for a robust regulatory framework to incorporate noise pollution mitigation strategies into the public health action plans of developing nations.

Hallmarks of Appetite: A Comprehensive Review of Hunger, Appetite, Satiation, and Satiety

PURPOSE OF REVIEW

The present review describes the available literature on the physiologic mechanisms that modulate hunger, appetite, satiation, and satiety with a particular focus on well-established and emerging factors involved in the classic satiety cascade model.

RECENT FINDING

Obesity is a significant risk factor for numerous chronic conditions like cancer, cardiovascular diseases, and diabetes. As excess energy intake is considered by some to be the primary driver of weight gain, tremendous collective effort should be directed toward reducing excessive feeding at the individual and population levels. From this perspective, detailed understanding of physiologic mechanisms that control appetite, and in turn, the design of effective interventions to manage appetite, may represent key strategies in controlling the obesity epidemic. With the obesity's prevalence on the rise worldwide, research on hunger, appetite, satiation and satiety is more relevant than ever. This research aims to provide practical insights for medical practitioners, nutrition professionals, and the broader scientific community in the fight against this global health challenge.

Association of extreme heat events with sleep and cardiovascular health: a scoping review

BACKGROUND

Extreme heat events (EHEs), driven by anthropogenic climate change, exacerbate the risk of cardiovascular disease (CVD), although the underlying mechanisms are unclear. A possible mechanism leading to heat-related CVD is disturbances in sleep health, which can increase the risk of hypertension, and is associated with ideal cardiovascular health. Thus, our objective was to systematically review the peer-reviewed literature that describes the relationship between EHEs, sleep health, and cardiovascular measures and outcomes and narratively describe methodologies, evidence, and gaps in this area in order to develop a future research agenda linking sleep health, EHEs, and CVD.

METHODS

A comprehensive literature search was performed in the following databases from inception-June 2023: Ovid MEDLINE, Ovid Embase, CINAHL, Web of Science, and the Cochrane Library. Studies retrieved were then screened for eligibility against predefined inclusion/exclusion criteria. Then studies were described qualitatively in relation to study design, findings, and the evidence linking the relationship between sleep health, EHEs, and CVD.

RESULTS

Of the 2035 records screened, only three studies met the inclusion criteria. In these three studies, EHE was measured as absolute temperatures (greater than 30 °C) or relative temperatures (i.e., 90th percentile daily maximum temperature within the region). Cardiovascular (CV) measures described included blood pressure (BP), heart rate (HR), and HR variability (no CVD outcomes were described), and objective and subjective measurements of sleep health outcomes included sleep duration, calmness, ease of falling asleep, ease of awakening, freshness after awakening, and sleep satisfaction. Two studies were controlled trials, and one was a cohort study. During EHEs, individuals slept for shorter periods of time and less efficiently, with greater degrees of HR variability in two of the three studies lasting at most 1-2 days; BP (both systolic and diastolic) significantly decreased during EHEs in two of the studies. No formal assessment of a mediating relationship between EHE exposure, sleep outcomes, and CV measures was undertaken.

CONCLUSIONS

Few studies examine the link between CVD, sleep, and extreme heat as a possible mechanism of elevated CVD risk during EHEs, despite a strong physiological rationale. Our findings highlight an important gap in the literature that should be closely examined as EHEs become more frequent and their harmful impacts of health increase.

Assessment of the relationship between post-earthquake trauma levels, sleep disorders, dietary habits, and emotional eating in adults

This study aimed to assess post-earthquake trauma levels in adults and explore the relationship between trauma, sleep disorders, dietary habits, and emotional eating. Conducted with 708 adults using snowball sampling, the study utilized the PROMIS Sleep Disturbance Scale, the Post-earthquake Trauma Level Determination Scale, and the Feeding Your Feelings: Emotional Eating Scale. Results revealed that factors such as gender, exposure to earthquake-related content on social media, time spent on social media before sleep, losing a loved one, and emotional eating tendencies significantly influenced trauma levels (Adj. R²:0.166, p<0.001). Bidirectional relationships were found between trauma, sleep disorders, and emotional eating. Given the results achieved, the earthquake on 6 February not only triggered trauma among individuals living in the affected regions but also across the entire society, negatively impacting dietary habits. These findings underscore the importance of psychosocial support after natural disasters to mitigate negative effects like sleep issues and emotional eating.

Accelerometer-derived sleep metrics in adolescents reveal shared genetic influences with obesity and stress in a Brazilian birth cohort study

We aimed to test the association between sleep-related polygenic scores (PGSs) and accelerometer-based sleep metrics among Brazilian adolescents and to evaluate potential mechanisms underlying the association through the enrichment of obesity, and cortisol pathway-specific polygenic scores (PRSet). Utilizing data from The 2004 Pelotas (Brazil) Birth Cohort, sleep time window and sleep efficiency were measured at the 11-year-old follow-up using ActiGraph accelerometers. Three sleep PGSs were developed based on the most recent genome-wide association study of accelerometer-based sleep measures. PRSet, calculated using variants linked to body mass index (BMI) and plasmatic cortisol concentration, aimed to assess pleiotropic effects. Linear regression models, adjusted for sex and the first 10 principal components of ancestry, were employed to explore the impact of sleep PGS and specific-PRSet on sleep phenotypes. The number of nocturnal sleep episodes-PGS was positively associated with sleep time window (β = 2.306, SE: 0.92, p = .011). Nocturnal sleep episodes were also associated with sleep time window when restricted to BMI-PRSet (β = 2.682, SE: 0.912, competitive p = .003). Both the number of sleep episodes and sleep time window cortisol-PRSets were associated (β = .002, SE: 0.001, p = .013; β = .003, SE: 0.001, p = .003, respectively) and exhibited enrichment in molecular pathways (competitive p = .011; competitive p = .003, respectively) with sleep efficiency. Sleep polygenetic components observed in European adults may partially explain the accelerometer-based sleep time window in Brazilian adolescents. Specific BMI molecular pathways strengthened the association between sleep PGS and sleep time window, while the cortisol concentration pathway had a significant impact on the genetic liability for sleep efficiency. Our results suggest genetic overlap as a potential etiological pathway for sleep-related comorbidities, emphasizing common genetic mechanisms.

Chronic low-dose REV-ERBs agonist SR9009 mitigates constant light-induced weight gain and insulin resistance via adipogenesis modulation

BACKGROUND

Obesity and circadian rhythm disruption are significant global health concerns, contributing to an increased risk of metabolic disorders. Both adipose tissue and circadian rhythms play critical roles in maintaining energy homeostasis, and their dysfunction is closely linked to obesity. This study aimed to assess the effects of chronic low-dose SR9009, a REV-ERB ligand, on circadian disruption induced by constant light exposure in mice.

MATERIAL AND METHODS

Mice were exposed to constant light for eight weeks (LL mice), resulting in increased body weight, insulin resistance, white fat mass, and altered circadian clock gene expression. Low-dose SR9009 (10 mg/kg daily) was administered chronically to assess its impact on these metabolic disruptions.

RESULTS

LL mice treated with SR9009 for eight weeks showed reduced weight gain, insulin resistance, and white fat mass but no significant impact on overall energy homeostasis. SR9009 suppressed Bmal1 expression and restored Rev-erbα and Rev-erbβ expression in white and brown adipose tissue (WAT and BAT). In vitro studies using 3T3-L1 cells indicated that SR9009 inhibited adipogenesis, leading to further investigation in vivo. SR9009 restored ChREBP1a and Srebp-1c expression in BAT but did not affect inflammatory cytokine or adipokine gene expression, nor did it restore Fasn, Pparγ, and Prom1 expression in both WAT and BAT.

CONCLUSIONS

These findings suggest that SR9009 may be a potential therapeutic for preventing weight gain and insulin resistance caused by circadian disruptions, likely through adipogenesis inhibition, though its effects on other metabolic pathways remain limited at low doses.

Bone-brain communication mediates the amelioration of Polgonatum cyrtonema Hua polysaccharide on fatigue in chronic sleep-deprived mice

This study aimed to investigate the anti-fatigue efficacy and underlying mechanisms of Polygonatum cyrtonema Hua polysaccharide (PCP) in chronic sleep-deprived mice. Following three weeks of oral administration, PCP demonstrated significant efficacy in alleviating fatigue symptoms. This was evidenced by the prolonged swimming and rotarod time in the high-dose group of PCP, which increased by 73 % and 64 %, respectively. Additionally, serum activities of CAT, GSH-Px, and SOD enzymes rose by 53.56 %, 37.69 % and 53.67 %, respectively, while MDA, lactic acid and BUN levels decreased by 22.90 %, 17.48 % and 24.61 %. The crosstalk between bone and brain is crucial for maintaining energy homeostasis. Molecular docking studies indicated a spontaneous and strong mutual binding between PCP and the bone-promoting target protein BMPR1A. Furthermore, it was observed that PCP enhanced osteogenic differentiation via the BMP-2/Smad1 pathway, leading to an upregulation of osteocalcin expression, which in turn regulated neurotransmitter balance and improved central arousal capacity. Moreover, PCP treatment stimulated neurogenesis by activating the CREB/BDNF/Akt signaling cascade, exhibiting neurotrophic effects. Additionally, PCP increased AMPK phosphorylation and destabilized TXNIP, facilitating astrocyte glucose uptake, glycolysis, and lactate conversion to support neuronal activity. These findings suggested that PCP could effectively respond to energy demands through bone-brain crosstalk, ultimately exerting anti-fatigue properties.

Frequent Shifts During Chronic Jet Lag Uncouple Liver Rhythms From the Light Cycle in Male Mice

Circadian disruption is pervasive in modern society and associated with increased risk of disease. Chronic jet lag paradigms are popular experimental tools aiming to emulate human circadian disruption experienced during rotating and night shift work. Chronic jet lag induces metabolic phenotypes tied to liver and systemic functions, yet lack of a clear definition for how rhythmic physiology is impaired under these conditions hinders the ability to identify the underlying molecular mechanisms. Here, we compared 2 common chronic jet lag paradigms and found that neither induced arrythmicity of the liver and each had distinct effects on rhythmicity. Instead, more frequent 8-h forward shifts of the light schedule induced more severe misalignment and non-fasted hyperglycemia. Every other day shifts eventually uncoupled behavioral and hepatic rhythms from the light cycle, reminiscent of free-running conditions. These results point to misalignment, not arrhythmicity, as the initial disturbance tied to metabolic dysfunction in environmental circadian disruption and highlight considerations for the interpretation and design of chronic jet lag studies.

Circadian Rhythms and Lung Cancer in the Context of Aging: A Review of Current Evidence

Circadian rhythm is the internal homeostatic physiological clock that regulates the 24-hour sleep/wake cycle. This biological clock helps to adapt to environmental changes such as light, dark, temperature, and behaviors. Aging, on the other hand, is a process of physiological changes that results in a progressive decline in cells, tissues, and other vital systems of the body. Both aging and the circadian clock are highly interlinked phenomena with a bidirectional relationship. The process of aging leads to circadian disruptions while dysfunctional circadian rhythms promote age-related complications. Both processes involve diverse physiological, molecular, and cellular changes such as modifications in the DNA repair mechanisms, mechanisms, ROS generation, apoptosis, and cell proliferation. This review aims to examine the role of aging and circadian rhythms in the context of lung cancer. This will also review the existing literature on the role of circadian disruptions in the process of aging and vice versa. Various molecular pathways and genes such as BMAL1, SIRT1, HLF, and PER1 and their implications in aging, circadian rhythms, and lung cancer will also be discussed.

The impact of sleep deprivation on the functional connectivity of visual-related brain regions

BACKGROUND

Sleep deprivation(SD) is known to impair cognitive function and emotional regulation, however, its specific effects on the functional connectivity of visual-related brain regions remain unclear.

OBJECTIVES

This study aimed to investigate the impact of 36-h acute sleep deprivation on functional connectivity in visual neural circuits and its relationship with cognitive and emotional changes.

METHODS

Sixty healthy male participants were assessed before and after 36 h of sleep deprivation using resting-state fMRI, the Psychomotor Vigilance Task (PVT), the Epworth Sleepiness Scale (ESS), and the Profile of Mood States (POMS). Functional connectivity changes were analyzed using paired t-tests and False Discovery Rate (FDR) correction.

KEY RESULTS

Sleep deprivation significantly altered functional connectivity between the prefrontal cortex, hippocampus, and visual processing regions. These changes correlated with slower PVT reaction times, increased subjective sleepiness (ESS), and emotional disturbances (POMS), including heightened tension and reduced self-esteem.

CONCLUSIONS

The findings suggest that acute sleep deprivation impairs cognitive performance and emotional regulation by changing functional connectivity in key brain regions. These results may strengthen our understanding of neurobiology of SD and its potential negative effects.

Associations between objectively measured nighttime sleep duration, sleep timing, and sleep quality and body composition in toddlers in the Guelph Family Health Study

The prevalence of child obesity is a worldwide public health concern. Good sleep quality is associated with reduced adiposity in older children and adults. More research is needed in younger children to help mitigate risk of obesity. In addition, we aimed to address limitations found in previous studies such as relying on subjective measures, or only including one parameter of sleep, using only one body composition parameter, and/or not adjusting for relevant covariates. This cross-sectional study examined baseline data from 48 toddlers aged 1 to <3 years enrolled in the Guelph Family Health Study. Nighttime sleep duration (total sleep time; TST), sleep timing (sleep onset and offset time), and sleep quality (wake after sleep onset; WASO) were measured using 24 h accelerometry for 7 consecutive days. Height, body weight, and waist circumference were measured, and BMI z-scores and waist-to-height ratios were calculated. Percent fat mass and fat mass index were calculated using bioelectrical impedance analysis. Linear regression models were used to estimate associations between sleep parameters and body composition outcomes, with adjustments for relevant covariates (age, sex, household income, screen time, energy intake, physical activity, household stress). Nighttime sleep onset time was positively associated with waist-to-height ratio (β ̂ = 0.004, p = 0.04). Sleep offset time was negatively associated with BMI z-score (β ̂ = -0.48, p = 0.02). TST and WASO were not associated with any body composition outcome. Building healthy sleep habits may prevent childhood obesity; longitudinal research in a larger sample is warranted. This study was registered on ClinicalTrials.gov (NCT02939261).

The intertwined relationship between circadian dysfunction and Parkinson's disease

Neurodegenerative disorders represent a leading cause of disability among the elderly population, and Parkinson's disease (PD) is the second most prevalent. Emerging evidence suggests a frequent co-occurrence of circadian disruption and PD. However, the nature of this relationship remains unclear: is circadian disruption a cause, consequence, or a parallel feature of the disease that shares the same root cause? This review seeks to address this question by highlighting and discussing clinical evidence and findings from experiments using vertebrate and invertebrate animal models. While research on causality is still in its early stages, the available data suggest reciprocal interactions between PD progression and circadian disruption.

Isobicyclogermacrenal ameliorates hippocampal ferroptosis involvement in neurochemical disruptions and neuroinflammation induced by sleep deprivation in rats

BACKGROUND

Sleep deprivation (SLD) is a widespread condition that disrupts physiological functions and may increase mortality risk. Valeriana officinalis, a traditional medicinal herb known for its sedative and hypnotic properties, contains isobicyclogermacrenal (IG), a newly isolated active compound. However, research on the therapeutic potential of IG for treating SLD remains limited.

METHODS

In this study, IG was extracted and characterized from Valeriana officinalis, and an SLD model was established in rats using p-chlorophenylalanine (PCPA). Behavioral tests and pathological studies were conducted to assess the effects of IG on SLD, and transcriptomic and metabolomic analyses were utilized to investigate its underlying mechanisms.

RESULTS

IG administration significantly improved the cognitive performance of SLD rats in behavioral tests and ameliorated histological injuries in the hippocampus and cerebral cortex. IG treatment increased the levels of brain-derived neurotrophic factor (BDNF) and neurotransmitters such as serotonin (5-HT) in SLD rats. Additionally, IG directly targets TFRC, thereby improving iron metabolism in the hippocampus. Comprehensive transcriptomic and metabolomic analyses revealed that the improvements from IG stemmed from the mitigation of abnormalities in iron metabolism, cholesterol metabolism, and glutathione metabolism, leading to reduced oxidative stress, ferroptosis, and neuroinflammation in the hippocampus caused by SLD.

CONCLUSIONS

Collectively, these findings suggest that IG has the potential to ameliorate neurological damage and cognitive impairment caused by SLD, offering a novel strategy for protection against the adverse effects of SLD.

Weekday-Weekend Differences in Chrononutritional Variables Depend on Urban or Rural Living

BACKGROUND/OBJECTIVES

Studies have highlighted the impact of work and school schedules on food preferences, suggesting that individuals' dietary choices may change during the week to align with their daily routines. Despite the variation in food composition in the population, there is no evidence identifying differences in food intake times and composition across the days of the week in urban/rural locations. Thus, the study's aim was to identify weekday vs. weekend differences in food intake times and composition (calories) between urban and rural areas.

METHODS

Data from 5770 participants (aged 18-59 years) were analyzed from the National Household Budget Survey (POF-IBGE) consisting of two distinct food diary records (weekday + weekend) per individual, including area (urban or rural) information in Brazil.

RESULTS

During weekdays, the time of the first food intake was significantly earlier, and the last food intake time was significantly later compared to weekends, resulting in a longer eating window on weekdays in both urban and rural areas. People living in urban areas exhibited delayed first and last food intake times, resulting in later caloric and eating midpoints compared to people living in rural areas. Periodogram analysis detected weekly rhythmicity (7 days) at the time of the first food intake and the length of the eating window in urban residents.

CONCLUSIONS

The observed 7-day rhythmic pattern of food intake in urban areas, driven by work and school schedules, underscores the influence of urbanization on dietary timing and composition. In contrast, rural areas exhibited more stable and earlier eating patterns. These results emphasize the need for public health interventions to address meal timing and circadian alignment, particularly in urban settings, to mitigate the risk of metabolic disorders and improve overall health outcomes.

S100A8 knockdown activates the PI3K/AKT signaling pathway to inhibit microglial autophagy and improve cognitive impairment mediated by chronic sleep deprivation

OBJECTIVE

Cognitive dysfunction is one of the major symptoms of chronic sleep deprivation (CSD). Abnormal autophagy and apoptosis are thought to be important mechanisms. S100 Calcium Binding Protein A8 (S100A8) plays a key role in autophagy and apoptosis of microglia. This study investigated whether S100A8 knockdown can effectively inhibit aberrant autophagy in microglia and improve cognitive function by activating the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway under CSD conditions.

METHODS

CSD mouse models and BV2 cell autophagy models were established in vivo and in vitro. Transcriptome sequencing was used to determine the key regulator related to autophagy. The Morris water maze test was used to evaluate the cognitive behavior of the mice. RT-qPCR and western blot were conducted to examine S100A8 expression and autophagy signalling. HE, TUNEL, transmission electron microscopy, immunofluorescence, and histochemistry were performed to detect pathological changes, neuronal autophagy, apoptosis, or positive cells in hippocampal tissues, respectively.

RESULTS

Transcriptome sequencing showed that S100A8 was significantly elevated in CSD mice, and fluorescence colocalization results further suggested that S100A8 mainly colocalizes with microglia. In vivo studies revealed that knockdown of S100A8 alleviated CSD-induced cognitive impairment in mice. Through further mechanistic investigations employing both in vivo and in vitro models, we demonstrated that silencing S100A8 can activate the PI3K/AKT pathway, thereby reducing CSD-induced abnormal autophagy and apoptosis in microglia. Aberrant autophagy and apoptosis in microglia were reversed with the PI3K/AKT pathway inhibitor LY294002.

CONCLUSION

The S100A8/PI3K/AKT axis plays a crucial role in chronic sleep deprivation-mediated autophagy and apoptosis in microglia.

Chronic sleep deprivation disturbs energy balance modulated by suprachiasmatic nucleus efferents in mice

BACKGROUND

Epidemiologic researches show that short sleep duration may affect feeding behaviors resulting in higher energy intake and increased risk of obesity, but the further mechanisms that can interpret the causality remain unclear. The circadian rhythm is fine-tuned by the suprachiasmatic nucleus (SCN) as the master clock, which is essential for driving rhythms in food intake and energy metabolism through neuronal projections to the arcuate nucleus (ARC) and paraventricular nucleus (PVN).

RESULTS

We showed that chronic SD-induced aberrant expressions of AgRP/NPY and POMC attributed to compromised JAK/STAT3 signals and reduced energy expenditure in the mice, which can be rescued with AAV-genetic overexpression of BMAL1 into SCN. The potential mechanism may be related to the disruptions of SCN efferent mediated by BMAL1.

CONCLUSIONS

Chronic SD impairs energy balance through directly dampening BMAL1 expression, probably in the transcription level, in the SCN, which in turn affects the neuron projections to ARC and PVN. Remarkably, we provide evidence that may explain the causal mechanisms associated with sleep curtailment and obesity in adolescents.

Impact of eating duration on weight management, sleeping quality, and psychological stress: A pilot study

The daily eating window significantly impacts weight and metabolic health, yet its ideal duration remains uncertain. Thirty-four healthy middle-aged women were randomly assigned to two intervention groups: 8-h time-restricted eating (TRE) and 14-h time-extended eating (EXE). Each intervention lasted 4 wk, with a 16-d washout period before switching to the other intervention. Clinical biomarkers were collected before and after each intervention, and sleep quality was assessed using the Korean Version of the Pittsburgh Sleep Quality Index (PSQI-K). Additionally, a daily visual analogue scale (VAS) was used to evaluate psychological changes. The TRE group experienced significant weight reduction, lower fasting plasma glucose and total serum cholesterol levels compared to the EXE group, but with an increase in systolic blood pressure. The EXE group showed improved blood pressure. The TRE group reported higher stress levels on the VAS, but the PSQI-K indicated improved sleep quality during the second intervention. An 8-h TRE, without calorie restriction or diet composition changes, proves more beneficial for weight management and plasma glucose control compared to the 14-h EXE among Korean women. Implementation of this approach is recommended to be gradual to mitigate psychological fluctuations and adverse blood pressure changes. The trial was registered with ClinicalTrials.gov (ID: NCT05964179) and Clinical Research Information Service (CRIS, Korea) (ID: KCT0008640).

Circadian Regulation of Fatty Acid Metabolism in Humans: Is There Evidence of an Optimal Time Window for Maximizing Fat Oxidation During Exercise?

Exercise training performed at the intensity that elicits maximal fat oxidation improves cardiovascular function and metabolic health while simultaneously reducing visceral adipose tissue in patients with obesity and type 2 diabetes. Indeed, it is currently considered an efficient non-pharmacological approach for the prevention and treatment of cardiometabolic disorders. Over the last 5 years, several studies have reported a diurnal variation in both resting fat oxidation as well as maximal fat oxidation recorded during submaximal intensity exercise. Higher fat oxidation has been recorded during the evening in comparison with the early morning, although this has not been universally observed. If evening exercise increases fat oxidation, then this timing of exercise may be preferable for the reversal of cardiometabolic diseases. However, the physiological and molecular mechanisms behind the circadian regulation of fatty acid metabolism have not yet been fully elucidated. The present review thus aims to describe the circadian rhythmicity of several hormones, metabolites, and enzymes involved in fatty acid mobilization and oxidation. Furthermore, we discuss the relevance of circadian mitochondrial dynamics and oxidative phosphorylation to fatty acid metabolism. To conclude our discussion, we highlight those biological (e.g., age and sex) and lifestyle factors (e.g., sleep quality/disturbances or physical activity) that potentially influence the circadian regulation of fatty metabolism and which therefore should be considered for a tailored exercise prescription.

Sleep deprivation alters hepatic UGT1A9 and propofol metabolism in mice

Sleep deprivation (SD) causes circadian misalignment, and circadian clock disruption is associated with metabolic diseases such as obesity, insulin resistance, and diabetes. However, the underlying mechanism for SD-induced circadian clock disruption as well as metabolic enzyme changes is still lacking. Here, we developed SD sensitizes mice with disrupted circadian rhythms to demonstrate the regulation role and mechanism of SD in UDP-glucuronosyltransferases (UGTs) expression and the metabolism of corresponding substrates. We found that UGT Family 1 Member A9 (UGT1A9) expression was significantly decreased in the liver of SD mice, which led to an elevation exposure and prolonged anesthesia effect of propofol, which was attributed to the decreased metabolism. Meanwhile, SD down-regulated basic helix-loop-helix ARNT like 1 (BMAL1) and its target clock genes period circadian clock (Per), cryptochrome circadian regulator (Cry), and nuclear receptor subfamily 1 group D member 1 (Rev-erb) expression in mice. Furthermore, the positive regulation of UGTIA9 mRNA and protein levels by Bmal1 was confirmed in hepatocyte-specific Bmal1-knockout mice (Bmal1-hkO) and Bmal1-overexpressed AML-12 cells. At last, through a combination of promoter analysis, luciferase reporter assay, and chromatin immunoprecipitation (ChIP) assay, it was conducted that Bmal1 regulates Ugtla9 expression by directly binding the -864 bp E-box in Ugtla9 promotor or indirectly acting on the Rev-erbα- differentiated embryo chondrocyte 2 (Dec2) axis. In conclusion, our findings suggested that SD can lead to altered drug disposition and effects in vivo, and Bmal1 plays a crucial role in the crosstalk between SD-induced circadian clock disruption and drug metabolism. It initiates a new direction for the understanding of drug efficacy and toxicity changes in SD conditions and provides a scientific basis for improving the rationality of drug use.

Impaired Vigilance in Patients with Narcolepsy Type 1: A Psychomotor Vigilance Task Study

Purpose

The psychomotor vigilance task (PVT) is one of the main methods to measure sustained vigilance/attention in sleep research. Vigilance is the main factor affecting daytime function in patients with narcolepsy type 1 (NT1). We aimed to quantify the negative effects of sleep-wake disorders on vigilance and investigate potential neural mechanisms.

Patients and Methods

We compared data from 42 patients and 31 healthy controls, including sociodemographics, nighttime sleep quality (Pittsburgh Sleep Quality Index, PSQI), sleepiness (Epworth Sleepiness Scale, ESS), cognitive abilities (Montreal Cognitive Assessment, MoCA), emotional control (Barratt Impulsiveness Scale-11, BIS-11), depressive symptoms (Patient Health Questionnaire-9, PHQ-9), and PVT performance. PVT outcomes analyzed included number of lapses, reaction time (RT), variability in RT, and the slowest and fastest 10% of RTs. All patients were diagnosed with NT1 based on The International Classification of Sleep Disorders-Third Edition.

Results

Patients with NT1 had a significantly higher body mass index and longer duration of education than healthy controls. The patients also had a greater tendency for daytime sleepiness and poorer nighttime sleep quality, higher depression and impulsiveness scores, and more severe cognitive dysfunction. PVT performance was better in the healthy controls than in patients with NT1. We also noticed that emotional changes and the proportion of rapid eye movement sleep at night are related to PVT performance.

Conclusion

More severe sleepiness and an increased emotional burden could underlie the arousal and vigilance deficits seen in patients with NT1. We speculate that impaired vigilance in patients with NT1 is associated with abnormal brain function caused by a resource allocation imbalance related to hypothalamic orexin neuron damage, sleep inertia may also have a slight impact on this. Future studies should delve into this topic more deeply.

Gender Differences in Dietary Patterns and Eating Behaviours in Individuals with Obesity

BACKGROUND/OBJECTIVES

Obesity is a global health problem with significant chronic disease risks. This study examined gender differences in eating behaviour, body composition, eating frequency and time of hunger in an Italian cohort with obesity (BMI ≥ 30) to inform gender-specific management strategies.

METHODS

A retrospective analysis of 720 adults (51.5% female, mean age 44.4 ± 13.8 years) assessed body composition and eating behaviour using principal component analysis (PCA) to classify eating profiles (structured, irregular, social and disordered/impulsive eaters).

RESULTS

Males showed higher weight, abdominal circumference and fat mass, while females showed higher fat mass percentages (p < 0.001). Gender differences were observed in the frequency of meals (e.g., 54.7% of males and 64.7% of females consumed 4-5 meals per day, p = 0.0018) and the time of hunger (males: before dinner; females: morning hunger, p = 0.005). The PCA profiles revealed that the 'structured eaters' had a healthier body composition, whereas the 'disordered/impulsive eaters' had a higher fat mass. Irregular eaters were predominantly male (41.0%), while disordered eaters were predominantly female (39.9%) (p = 0.0016).

CONCLUSIONS

Gender-specific eating patterns influence obesity outcomes. Structured eating was associated with healthier profiles, whereas impulsive or irregular patterns were related to higher fat mass. The retrospective design and non-validated questionnaire for dietary behaviour assessment limit generalisability, warranting further research for tailored interventions.

REGISTRATION

ClinicalTrials.gov (NCT06654674).

Association Between Sleep Quality and Cirrhotic Cardiomyopathy: A Prospective Case-Control Study

Objective

The main purpose of this study is to evaluate the changes in sleep quality among patients with cirrhotic cardiomyopathy (CCM).

Methods

The study included liver cirrhosis patients aged 18-75 from Northern Jiangsu People's Hospital Affiliated to Yangzhou University and collected their clinical examination results to assess the clinical characteristics and related risk factors of patients with CCM.

Results

The study found that the onset of CCM was not related to the etiology of inducing cirrhosis. Pittsburgh Sleep Quality Index (PSQI) score (odds ratio (OR) = 13.476, 95% confidence interval (CI) = 1.514-119.923, P = 0.020), absolute GLS (OR = 0.328, 95% CI = 0.210-0.510, P < 0.001), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (OR = 1.050, 95% CI = 1.025-1.076, P < 0.001) were identified as independent risk factors for inducing CCM.

Conclusion

In patients with CCM, a decrease in sleep quality often occurs. When cirrhotic patients also have poor sleep quality, along with a decrease in absolute Global Left Ventricular Strain (GLS) levels and an increase in NT-proBNP levels, these factors may pose a higher risk for CCM development. However, further validation of these research findings is required in larger sample sizes.

The real-world association between digital markers of circadian disruption and mental health risks

While circadian disruption is recognized as a potential driver of depression, its real-world impact is poorly understood. A critical step to addressing this is the noninvasive collection of physiological time-series data outside laboratory settings in large populations. Digital tools offer promise in this endeavor. Here, using wearable data, we first quantify the degrees of circadian disruption, both between different internal rhythms and between each internal rhythm and the sleep-wake cycle. Our analysis, based on over 50,000 days of data from over 800 first-year training physicians, reveals bidirectional links between digital markers of circadian disruption and mood both before and after they began shift work, while accounting for confounders such as demographic and geographic variables. We further validate this by finding clinically relevant changes in the 9-item Patient Health Questionnaire score. Our findings validate a scalable digital measure of circadian disruption that could serve as a marker for psychiatric intervention.

Efficacy of morning versus afternoon aerobic exercise training on reducing metabolic syndrome components: A randomized controlled trial

A supervised intense aerobic exercise program improves the health of individuals with metabolic syndrome (MetS). However, it is unclear whether the timing of training within the 24 h day would influence those health benefits. The present study aimed to determine the influence of morning vs. afternoon exercise on body composition, cardiometabolic health and components of MetS. One hundred thirty-nine individuals with MetS were block randomized into morning (AMEX; n = 42) or afternoon (PMEX; n = 59) exercise training groups, or a non-training control group (Control; n = 38). Exercise training was comprised of 48 supervised high-intensity interval sessions distributed over 16 weeks. Body composition, cardiorespiratory fitness (assessed byV ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ ), maximal fat oxidation (FOmax), blood pressure and blood metabolites were assessed before and after the intervention. Compared with the non-training Control, both exercise groups improved similarly body composition (-0.7% fat loss; P = 0.002), waist circumference (-2.1 cm; P < 0.001), diastolic blood pressure (-3.8 mmHg; P = 0.004) andV ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ (3.5 mL kg-1  min-1; P < 0.001) with no differences between training groups. AMEX, in comparison with PMEX, reduced systolic blood pressure (-4% vs. -1%; P = 0.019), plasma fasting insulin concentration (-12% vs. -5%; P = 0.001) and insulin resistance (-14% vs. -4%; P = 0.006). Furthermore, MetS Z score was further reduced in the AMEX compared to PMEX (-52% vs. -19%; P = 0.021) after training. In summary, high-intensity aerobic exercise training in the morning in comparison to training in the afternoon is somewhat more efficient at reducing cardiometabolic risk factors (i.e. systolic blood pressure and insulin sensitivity). KEY POINTS: The effect of exercise time of day on health promotion is an area that has gained interest in recent years; however, large-scale, randomized-control studies are scarce. People with metabolic syndrome (MetS) are at risk of developing cardiometabolic diseases and reductions in this risk with exercise training can be precisely gauged using a compound score sensitive to subtle evolution in each MetS component (i.e. Z score). Supervised aerobic exercise for 16 weeks (morning and afternoon), without dietary restriction, improved cardiorespiratory and metabolic fitness, body composition and mean arterial pressure compared to a non-exercise control group. However, training in the morning, without changes in exercise dose or intensity, reduced systolic blood pressure and insulin resistance further compared to when training in the afternoon. Thus, high-intensity aerobic exercise training in the morning is somewhat more efficient in improving the health of individuals with metabolic syndrome.

Influence of extreme light/dark cycles on monoamine levels, physiological indices, and emotional behaviors in rats

Aberrant light/dark (LD) cycles are prevalent in modern society due to electric light usage, leading to mood disorders from circadian disruption or misalignment. However, research on the physiological and behavioral effects of LD variations on brain neurotransmitters is limited. We investigated the effects of extreme LD cycles on body weight (BW), core body temperature (Tcore), locomotor activity (ACT), emotional behaviors, and monoamine levels (noradrenaline [NA], dopamine [DA], and serotonin [5-HT]) in male Wistar rats that were exposed to 1 month of either long light phase (20 L:4D), long dark phase (4 L:20D), or normal (12 L:12D) LD cycles. The 20 L:4D rats exhibited blunted rhythms, with decreased amplitude and advanced/delayed acrophase in Tcore and ACT, alongside increased BW. The 4 L:20D rats showed circadian misalignment, with increased/decreased amplitude in Tcore or ACT and delayed acrophase in Tcore and ACT, also gaining BW. In the 20 L:4D group, NA and 5-HT levels decreased in the suprachiasmatic nucleus and amygdala, respectively, while the 4 L:20D group had increased DA and 5-HT levels in the caudate putamen and dorsomedial hypothalamus, respectively. Open field and social interaction tests indicated anxiety-like behaviors in both test groups. Overall, each extreme LD cycle affected Tcore, ACT amplitude, acrophase, and monoamine levels differently, inducing anxiogenic responses.

Sleep conditions and sleep hygiene behaviors in early pregnancy are associated with gestational diabetes mellitus: A propensity-score matched study

PURPOSE

To explore the influence of sleep conditions and sleep hygiene behaviors in early pregnancy on gestational diabetes mellitus (GDM) development.

METHODS

This 1:1 propensity-score matched study included 1,216 pregnant women divided into GDM and control groups based on diagnosis via the oral glucose tolerance test at 24-28 gestational weeks. Sleep conditions and hygiene behaviors were evaluated using structural questionnaires, including the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and Sleep Hygiene Practice Scale. Univariate and multivariate logistic regression analyses and Spearman's correlation were conducted to identify the associations.

RESULTS

After adjusting for baseline clinical characteristics, women with GDM were more likely to have poor sleep quality (adjusted odds ratio [AOR] = 1.585, 95% confidence interval [CI]: 1.261-1.992) and higher scores for subjective sleep quality, latency, duration, efficiency, and sleep disturbances (all P < 0.01). Mild sleepiness (AOR = 1.311, 95% CI: 1.012-1.699) and worrying about not being able to fall asleep (AOR = 1.123, 95% CI: 1.005-1.255) were more likely to occur in the GDM group. Sleep quality and hygiene behaviors such as sleep-irrelevant activities, staying in bed after waking up, weekend catch-up sleep, and overeating before bedtime were significantly correlated with gestational diabetes variables.

CONCLUSION

Poor sleep conditions and specific sleep hygiene behaviors in early pregnancy may be independent risk factors for GDM. This suggests that sleep assessment and behavior education can be used as new approaches for the early implementation of surveillance and prevention of GDM.

Latent profiles of multi-dimensional sleep characteristics and association with overweight/obesity in Chinese preschool children

OBJECTIVES

To examine the association between latent profiles of multi-dimensional sleep characteristics and overweight/obesity (OWO) in Chinese preschool children.

STUDY DESIGN

The cross-sectional analysis included 3204 preschool children recruited from 24 kindergartens in Shanghai. Parents reported children's demographics and sleep characteristics, including sleep duration, timing and disturbances. Latent profile analysis (LPA) was used to identify sleep subtypes. Logistic regression models were used to evaluate the associations between sleep characteristics/subtypes and OWO.

RESULTS

Short sleep duration, late bedtime, long social jetlag and sleep disturbances were significantly associated with increased OWO. However, when considering the interplay of sleep duration and timing, there was no significant association between sleep duration and OWO for children sleeping later than 22:00. Three sleep subtypes were identified based on children's sleep duration, timing and disturbances: "Average Sleepers" (n = 2107, 65.8 %), "Good Sleepers" (n = 481, 15.0 %), and "Poor Sleepers" (n = 616, 19.2 %). "Good Sleepers" had reduced odds of being OWO (AOR, 0.72; 95 % CI, 0.56-0.93) compared to "Average Sleepers", while "Poor Sleepers" showed an increased risk of OWO (AOR, 1.36; 95 % CI, 1.11-1.67).

CONCLUSIONS

These findings highlight that improving multiple sleep characteristics simultaneously is a promising option to prevent and intervene childhood obesity.

Novel insights into the circadian modulation of lipid metabolism in chicken livers revealed by RNA sequencing and weighted gene co-expression network analysis

The circadian clock is crucial for maintaining lipid metabolism homeostasis in mammals. Despite the economic importance of fat content in poultry, research on the regulatory effects and molecular mechanisms of the circadian clock on avian hepatic lipid metabolism has been limited. In this study, we observed significant diurnal variations (P<0.05) in triglyceride (TG), free fatty acids (FFA), fatty acid synthase (FAS), and total cholesterol (TC) levels in the chicken embryonic liver under 12-h light/12-h dark incubation conditions, with TG, FFA, and TC concentrations showing significant cosine rhythmic oscillations (P<0.05). However, such rhythmic variations were not observed under complete darkness incubation conditions. Using transcriptome sequencing technology, we identified 157 genes significantly upregulated at night and 313 genes significantly upregulated during the 12-h light/12-h dark cycle. These circadian differential genes are involved in processes and pathways such as lipid catabolic process regulation, meiotic cell cycle, circadian rhythm regulation, positive regulation of the MAPK cascade, and glycerolipid metabolism. Weighted gene co-expression network analysis (WGCNA) revealed 3 modules-green, blue, and red-that significantly correlate with FFA, FAS, and TG, respectively. Genes within these modules were enriched in processes and pathways including the cell cycle, light stimulus response, circadian rhythm regulation, phosphorylation, positive regulation of the MAPK cascade, and lipid biosynthesis. Notably, we identified ten hub genes, including protein kinase C delta (PRKCD), polo like kinase 4 (PLK4), clock circadian regulator (CLOCK), steroid 5 alpha-reductase 3 (SRD5A3), BUB1 mitotic checkpoint serine/threonine kinase (BUB1B), shugoshin 1 (SGO1), NDC80 kinetochore complex component (NDC80), NIMA related kinase 2 (NEK2), minichromosome maintenance complex component 4 (MCM4), polo like kinase 1 (PLK1), potentially link circadian regulation with lipid metabolic homeostasis. These findings demonstrate the regulatory role of the circadian clock in chicken liver lipid metabolism homeostasis and provide a theoretical basis and molecular targets for optimizing the circadian clock to reduce excessive fat deposition in chickens, which is significant for the healthy development of the poultry industry.

Association of Evening Eating with Sleep Quality and Insomnia among Adults in a Brazilian National Survey

Objective  To examine the association of evening eating clock time, its elapsed time to the midpoint of sleep (TEM), consumption of caffeine and sugary foods, and reporting dinner as the largest meal with sleep quality indicators and insomnia. Methods  Participants ( n  = 2,050;18-65y) were part of population-based research, with virtual data collection. Logistic regression models were fitted to assess differences in the ORs(95%CI) of sleep duration < 7 hours, sleep latency > 30 minutes, poor sleep quality, and insomnia (outcomes) with the evening diet-related variables. Linear regression analyses evaluated differences in sleep duration and latency associated with the same variables. Restricted cubic splines were used to study the shape of the association of eating event clock time and TEM with sleep duration and latency. Results  Each additional hour of evening eating clock time and of the TEM, respectively increased and decreased, the odds of sleep duration < 7/h [OR(95%CI):1.30(1.20,1.40); OR(95%CI):0.51(0.47,0.56)], sleep latency > 30min [OR(95%CI):1.14(1.07,1.22); 0.88(0.83,0.94)], poor sleep quality [OR(95%CI):1.21(1.13,1.30); 0.80(0.76,0.85)] and insomnia [OR(95%CI):1.12(1.04,1.20); 0.89(0.84,0.95)]. We found a dose-response association between evening eating (clock time and TEM) and sleep duration. The shortest latency was seen when evening eating was ∼20:00 and ∼7-8 hours before the midpoint of sleep. Participants who reported dinner as the largest meal and consumed caffeine and sugary foods/beverages after 18:00 presented higher odds of sleep duration < 7 hours, poor quality, and insomnia. Conclusions  Our findings indicate that an early-eating schedule has beneficial sleep effects and that it will be necessary to consider evening eating patterns and timing, along with the existing sleep and circadian hygiene, to improve sleep quality and circadian health.

Interaction of Clock gene variants and behavioral parameters influences adiposity-related traits

Obesity, a major health concern, is influenced by an individual's genetic makeup and lifestyle factors (eating, sedentary lifestyle, and sleep disruptions) that affect circadian clock and metabolism. This study investigates the impact of Clock gene variants rs6843722 and rs4864548 on obesity measures in the Pakistani population. Genetic-behavior interaction studies have focused on Western populations, overlooking South Asians. We included 306 overweight/obese and 306 normal-weight controls, matched for age and gender. Anthropometric measures (BMI, waist circumference, waist-to-height ratio, and body fat percentage) were taken using standard procedures while behavioral data (dietary and sleep-related behaviors, shiftwork, and physical activity) was collected by questionnaire. Genotyping was performed by Taqman assays. Data was analyzed using SPSS 19.0. Rank-based inverse normal transformation was executed for quantitative non-normal variables. The linear regression revealed that both Clock gene variants interacted significantly with dietary and sleep-related behaviors and low physical activity, impacting adiposity measures regardless of age and gender. Shiftwork interacted specifically with rs6843722, increasing body fat percentage. This study indicates that Clock gene variants, when interacting with lifestyle factors, play a substantial role in increasing obesity risk highlighting the link between lifestyle choices and disturbances in circadian rhythms controlled by Clock gene variations, ultimately leading to obesity.

Intrapancreatic fat deposition and nutritional treatment: the role of various dietary approaches

Ectopic fat accumulation in various organs and tissues, such as the liver, muscle, kidney, heart, and pancreas, is related to impaired capacity of adipose tissue to accumulate triglycerides, as a consequence of overnutrition and an unhealthy lifestyle. Ectopic fat promotes organ dysfunction and is a key factor in the development and progression of cardiometabolic diseases. Interest in intrapancreatic fat deposition (IPFD) has developed in the last few years, particularly in relation to improvement in methodological techniques for detection of fat in the pancreas, and to growing evidence for the role that IPFD might have in glucose metabolism disorders and cardiometabolic disease. Body weight reduction represents the main option for reducing fat, and the evidence consistently shows that hypocaloric diets are effective in reducing IPFD. Changes in diet composition, independently of changes in energy intake, might offer a more feasible and safe alternative treatment to energy restriction. This current narrative review focused particularly on the possible beneficial role of the diet and its nutrient content, in hypocaloric and isocaloric conditions, in reducing IPFD in individuals with high cardiometabolic risk, highlighting the possible effects of differences in calorie quantity and calorie quality. This review also describes plausible mechanisms by which the various dietary approaches could modulate IPFD.

Short-term exposure to indoor artificial light at night during sleep impairs cardiac autonomic function of young healthy adults in China

The artificial light at night (ALAN) exposure has emerged as a significant environmental and public health concern globally. However, there is far less evidence on the health effects of indoor ALAN than on outdoor ALAN. Moreover, evidence on cardiovascular effects of indoor ALAN is more limited. To evaluate the association between short-term exposure to ALAN during sleep with heart rate variability (HRV) in young healthy adults, as well as the mediating role of blood oxygen saturation (SpO2), and to further explore the intervention effects of shading habits, this prospective repeated measurement study was conducted among 81 adults with 150 nights (1324h) of HRV monitoring. HRV and SpO2 were monitored during sleep, concurrently with the measurement of indoor and outdoor ALAN. Shading habits were defined as whether to wear blindfolds or draw bed curtains during sleep, and were collected by questionnaires. Linear mixed-effect model was conducted to assess the association between ALAN exposure and HRV indices. The role of SpO2 in the association was analyzed using mediation analyses. We found that indoor ALAN exposure reduced parasympathetic activity and imbalanced cardiac autonomic function. We also found that the use of outdoor ALAN may underestimate or misestimate the potential health effects of ALAN. A significant mediation effects were observed on standard deviation of normal-to-normal intervals (SDNN; p-value for ACME = 0.014) and the ratio of low frequency power to high frequency power (LF/HF; p-value for ACME = 0.026) through minimum SpO2 after indoor ALAN exposure. The association between indoor ALAN and HRV was more pronounced among participants without shading habits during sleep. This study provides general population-based evidence that short-term exposure to indoor ALAN was significantly associated with impaired HRV, and SpO2 partially mediated the association. Improve shading habits during sleep may mitigate the adverse effects of indoor ALAN.

Association between sleep quality and duration during pregnancy and risk of gestational diabetes: A systematic review and meta-analysis

OBJECTIVE

Gestational diabetes mellitus (GDM) is associated with several adverse maternal and neonatal outcomes. Previous studies reported a link between altered sleep and risk of GDM. This systematic review aims to collate evidence on the association between impaired sleep quality and duration, and the risk of GDM.

METHODS

PubMed, Embase, Web of Science, and Scopus databases were searched up to January 20, 2024. Studies reporting the association between impaired sleep quality and duration and risk of GDM were included. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI). Random-effects meta-analysis was performed, and the results were reported as hazard ratio (HR) with 95% confidence interval (CI).

RESULTS

19 studies were included. Meta-analysis revealed a significant increase in the risk of GDM in pregnant women with poor sleep quality (i.e. <5 PSQI) (HR: 1.50, 95% CI: 1.26 - 1.78, p < .001). Sleep duration of <7 h (HR: 1.56, 95% CI.: 1.20 - 2.01, p < .001), and >8 h (HR: 2.32, 95% CI.: 1.19 - 4.50, p = .01) were also associated with a significantly higher incidence of GDM.

CONCLUSION

Sleep quality and duration emerge as critical risk factors of GDM. Healthcare practitioners should consider targeted interventions to improve sleep hygiene as a potential measure for GDM prevention.

Sleep extension and cardiometabolic health: what it is, possible mechanisms and real-world applications

Short sleep duration is associated with heightened cardiometabolic disease risk and has reached epidemic proportions among children, adolescents and adults. Potential mechanisms underlying this association are complex and multifaceted, including disturbances in circadian timing, food intake and appetitive hormones, brain regions linked to control of hedonic eating, physical activity, an altered microbiome and impaired insulin sensitivity. Sleep extension, or increasing total sleep duration, is an emerging and ecologically relevant intervention with significant potential to advance our understanding of the mechanisms underlying the association between short sleep duration and the risk of cardiometabolic disease. If effective, sleep extension interventions have potential to improve cardiometabolic health across the lifespan. Existing data show that sleep extension is feasible and might have potential cardiometabolic health benefits, although there are limitations that the field must overcome. Notably, most existing studies are short term (2-8 weeks), use different sleep extension strategies, analyse a wide array of cardiometabolic health outcomes in different populations and, frequently, lack adequate statistical power, thus limiting robust scientific conclusions. Overcoming these limitations will require fully powered, randomized studies conducted in people with habitual short sleep duration and existing cardiometabolic risk factors. Additionally, randomized controlled trials comparing different sleep extension strategies are essential to determine the most effective interventions. Ongoing and future research should focus on elucidating the potential cardiometabolic health benefits of sleep extension. Such studies have high potential to generate crucial knowledge with potential to improve health and quality of life for those struggling with short sleep duration.

Association of Social Jetlag with the Dietary Quality Among Korean Workers: Findings from a Nationwide Survey

Background/Objectives: Social jetlag, which refers to the misalignment between biological rhythms and social schedule, is linked to an increased risk of metabolic diseases. This cross-sectional study investigated the relationship between social jetlag and workers' dietary quality. Methods: This secondary data analysis included a sample of workers from the Korea National Health and Nutrition Examination Survey (n = 11,430). Social jetlag was determined by calculating the difference in the sleep midpoint between free days and workdays, based on sleep onset and offset times. The Korean Health Eating Index (KHEI) was calculated based on 24-h recalls, with higher scores indicating superior dietary qualities (range: 0-100). Poor dietary quality was defined as a KHEI below the lowest quartile (<51.6). Linear or logistic regressions were utilized to estimate β or odds ratio (OR), respectively. Results: Among study participants, 12.1% of workers experienced ≥120 min of social jetlag. ≥120 min of social jetlag was associated with a reduced KHEI score compared with 0-59 min (β: -1.23, 95% confidence interval [CI]: -2.16, -0.30). Those with ≥120 min of social jetlag were more likely to have poor dietary quality than those with 0-59 min (OR: 1.27, 95% CI: 1.08, 1.50). Conclusions: Workers experiencing ≥120 min of social jetlag had poorer dietary quality compared with workers with 0-59 min of social jetlag. Therefore, this study suggests that policy efforts are needed to reduce social jetlag among workers in Korea.

Association between sleep and gallstone disease in United States adults: A cross-sectional study

BACKGROUND

Both gallstone disease and sleep disorders are important public health problems. Few studies to date have investigated the associations between sleep and gallstone disease in humans. This study aimed to assess whether sleep factors (sleep time, sleep amounts, trouble sleeping) were associated with gallstone disease in the United States adults.

METHODS

This was a population-based cross-sectional study of US adults, which included data of participants aged over 20 years from the National Health and Nutrition Examination Survey (NHANES) gathered between 2017 and March 2020. The assessment of gallstone disease and sleep factors was based on self-reported data. We used sample-weighted logistic regression and restricted cubic spline models to explore the associations between sleep factors and gallstone disease. Subgroup analyses were conducted to assess the interaction between trouble sleeping and interacting factors.

RESULTS

The prevalence of gallstone disease was 11% among the 9,210 adult participants. Going to bed late on weekdays (OR, 1.41; 95% CI, 1.15 to 1.74) and weekends (OR, 1.43; 95% CI, 1.14 to 1.78), and short sleep duration on weekdays (OR, 1.29; 95% CI, 1.00 to 1.68) were factors associated with increased risk of gallstone disease, and we detected dose-response associations with the restricted cubic spline model (RCS) models, after adjusting for confounders. Presenting trouble sleeping was associated with increased risk of gallstone disease (OR, 1.52; 95% CI, 1.03 to 2.23) and the association was influenced by the presence of thyroid disease (P for interaction = 0.037).

CONCLUSIONS

Our study results indicate that going to bed late, short sleep duration, and trouble sleeping were associated with increased risk of gallstone disease in a nationally representative sample of adults in the US.

Correlation between sleep duration and prevalence of hypertension: the China Health and Nutrition Survey

It is increasingly thought that sleep is a lifestyle factor that contributes to hypertension. However, the correlation between sleep duration and hypertension in the Chinese population remains largely unexplored. This study utilized data from the 2009 China Health and Nutrition Survey to investigate the correlation between sleep duration and hypertension. Average hours of sleep per day were grouped into following categories: ≤6, 7-9, and ≥10 h. The frequency of hypertension and odds ratio (OR) were computed across different sleep duration categories. Individuals sleeping 7-9 h per day were designated as the control group. Logistic regression was utilized for multivariate analysis. Among the 9435 participants, the mean sleep duration was 7.9±1.2 h. The prevalence of hypertension was 34.1, 21.7, and 29.3% for individuals sleeping ≤6, 7-9, and ≥10 h per day, respectively. Following adjustments for age, gender, body mass index, and diabetes, a significant association was observed between prolonged (≥10 h) sleep duration and hypertension. Compared to those sleeping 7-9 h per day, the OR for hypertension was 1.21 (95%CI: 1.02-1.43, P=0.03) for individuals sleeping ≥10 h per day. This study suggested that sleeping ≥10 h per day is associated with a higher risk of hypertension in adults.

Chronic Sleep Deprivation Causes Anxiety, Depression and Impaired Gut Barrier in Female Mice-Correlation Analysis from Fecal Microbiome and Metabolome

BACKGROUND

Chronic sleep deprivation (CSD) plays an important role in mood disorders. However, the changes in the gut microbiota and metabolites associated with CSD-induced anxiety/depression-like behavior in female mice have not been determined. Due to the influence of endogenous hormone levels, females are more susceptible than males to negative emotions caused by sleep deprivation. Here, we aim to investigate how CSD changes the gut microbiota and behavior and uncover the relationship between CSD and gut microbiota and its metabolites in female mice.

METHODS

We used a 48-day sleep deprivation (SD) model using the modified multiple platform method (MMPM) to induce anxiety/depression-like behavior in female C57BL/6J mice and verified our results using the open field test, elevated plus maze, novel object recognition test, forced swim test, and tail suspension test. We collected fecal samples of mice for 16S rDNA sequencing and untargeted metabolomic analysis and colons for histopathological observation. We used Spearmen analysis to find the correlations between differential bacterial taxa, fecal metabolites, and behaviors.

RESULTS

Our study demonstrates that CSD induced anxiety/depressive-like behaviors in female mice. The results of 16S rDNA sequencing suggested that the relative abundance of the harmful bacteria g_ Rothia, g_ Streptococcus, g_ Pantoea, and g_ Klebsiella were significantly increased, while the beneficial bacteria g_ Rikenella, g_ Eubacterium]-xylanophilum-group, and g_ Eisenbergiella were significantly decreased after SD. Glycerophospholipid metabolism and glutathione metabolism were identified as key pathways in the fecal metabolism related to oxidative stress and inflammatory states of the intestine. Histological observation showed hyperplasia of epithelial cells, a decrease in goblet cells, and glandular atrophy of the colon in SD mice. There were correlations between some of the differential bacterial taxa, fecal metabolites, and behaviors.

CONCLUSION

In summary, we found that CSD induced anxiety/depression-like behavior, caused gut microbiota dysbiosis, altered fecal metabolism, and damaged the colon barrier in female mice.

Beyond the Scale: Exploring the Endocannabinoid System's Impact on Obesity

PURPOSE OF REVIEW

This review explores the role of the endocannabinoid system (ECS) in regulating energy balance, food intake, and metabolism, with a focus on how ECS dysregulation contributes to obesity. The goal is to provide insights into the mechanisms underlying obesity and its associated metabolic disorders.

RECENT FINDINGS

Recent research indicates that the ECS significantly influences food intake, fat storage, insulin sensitivity, and inflammation, all of which are central to the development and progression of obesity. New research areas include the interaction between the ECS and gut microbiota, circadian rhythms of the ECS, and the impact of genetic and epigenetic factors on ECS function. Interest in the therapeutic potential of targeting the ECS has grown, with earlier treatments like CB1 receptor antagonists showing mixed results in efficacy and safety. Evidence from both animal and human studies highlight the impact of elevated levels of the endocannabinoids anandamide and 2-AG on food intake, insulin resistance, visceral fat accumulation, and metabolic disturbances associated with obesity. The review explores the interaction between the ECS and other physiological systems, including gut-brain communication, circadian rhythms, as well as leptin and ghrelin signaling. Additionally, genetic and epigenetic factors influencing ECS function are examined, emphasizing their contribution to obesity susceptibility. While therapeutic approaches targeting the ECS, particularly CB1 receptor antagonism, have shown potential in managing obesity, the review acknowledges the challenges posed by central nervous system side effects in earlier treatments like rimonabant. However, recent advancements in peripherally restricted CB1 antagonists offer renewed hope for safer and more effective obesity treatments. The review concludes by addressing future research directions and therapeutic strategies to combat this global health challenge.

Suboptimal health among Chinese middle school students may be associated with psychological symptoms and sleep duration: a cross-sectional survey in China

BACKGROUND

Suboptimal health status (SHS) is an intermediate status between ideal heath and illness, it is characterized by the perception of health complaints, general weakness, decreased immunity and low energy. An increasing number of Chinese middle school students are suffering from psychological symptoms (PS), particularly anxiety and depression. The relationship between SHS and PS is unclear in adolescents. This study aimed to investigate the prevalence of SHS and the correlation between SHS and PS among Chinese middle school students and to identify the SHS-related risk factors from the perspective of public health.

METHODS

A cross-sectional study was conducted with the cluster sampling method among 1955 middle school students in Shantou, China. SHS was assessed by Suboptimal Health Status Questionnaire-25 (SHSQ-25). And the PS of anxiety and depression were assessed with Generalized Anxiety Disorder Scale (GAD-7) and Beck Depression Inventory-II Scale (BDI-II) self-assessment questionnaires. Variate logistic analysis was applied to explore risk factors of SHS. The relationship between SHS and PS among Chinese middle school students was subsequently analyzed.

RESULTS

Among the 1955 participants, 1904 middle school students were finally included in the analysis, the effective response rate was 97.39%. The prevalence of SHS was 10.3% (197/1904) while the prevalence of anxiety and depression was 30.7% (585/1904) and 34.1% (649/1904), respectively. A strong correlation was identified between SHS and PS among middle school students. With the aggravation of anxiety and depression, the probability of suffering from SHS increased (both P<0.01). The scores for various dimensions of SHS among the depression and anxiety groups were higher compared to those of the non-depression and non-anxiety groups (all P<0.01 ). Multivariate regression showed that compared with sleeping less than six hours, 6-8 h is a protective factor for SHS (OR = 0.486, 95%CI = 0.278-0.851).

CONCLUSIONS

Attention should be given to SHS and PS in Chinese middle school students, as they are strongly associated. Lack of sleep is a risk factor for SHS, so sufficient sleep should be recommended to prevent it. Identifying additional risk factors and promoting adequate sleep will improve adolescent health.

Hepatic vagal afferents convey clock-dependent signals to regulate circadian food intake

Circadian desynchrony induced by shiftwork or jet lag is detrimental to metabolic health, but how synchronous or desynchronous signals are transmitted among tissues is unknown. We report that liver molecular clock dysfunction is signaled to the brain through the hepatic vagal afferent nerve (HVAN), leading to altered food intake patterns that are corrected by ablation of the HVAN. Hepatic branch vagotomy also prevents food intake disruptions induced by high-fat diet feeding and reduces body weight gain. Our findings reveal a homeostatic feedback signal that relies on communication between the liver and the brain to control circadian food intake patterns. This identifies the hepatic vagus nerve as a potential therapeutic target for obesity in the setting of chronodisruption.