Chronobiology International

doi: 10.1080/07420528.2023.2216577pmid: 37222599

Ballester Roig, Maria Neus; Roy, Pierre-Gabriel; Hannou, Lydia; Delignat-Lavaud, Benoît; Sully Guerrier, Thomas-Andrew; Bélanger-Nelson, Erika; Dufort-Gervais, Julien; Mongrain, Valérie

doi: 10.1080/07420528.2023.2237580pmid: 37551686

Circadian rhythms originate from molecular feedback loops. In mammals, the transcription factors CLOCK and BMAL1 act on regulatory elements (i.e. E-boxes) to shape biological functions in a rhythmic manner. The EPHA4 receptor and its ligands Ephrins (EFN) are cell adhesion molecules regulating neurotransmission and neuronal morphology. Previous studies showed the presence of E-boxes in the genes of EphA4 and specific Ephrins, and that EphA4 knockout mice have an altered circadian rhythm of locomotor activity. We thus hypothesized that the core clock machinery regulates the gene expression of EphA4, EfnB2 and EfnA3. CLOCK and BMAL1 (or NPAS2 and BMAL2) were found to have transcriptional activity on distal and proximal regions of EphA4, EfnB2 and EfnA3 putative promoters. A constitutively active form of glycogen synthase kinase 3β (GSK3β; a negative regulator of CLOCK and BMAL1) blocked the transcriptional induction. Mutating the E-boxes of EphA4 distal promoter sequence reduced transcriptional induction. EPHA4 and EFNB2 protein levels did not show circadian variations in the mouse suprachiasmatic nucleus or prefrontal cortex. The findings uncover that core circadian transcription factors can regulate the gene expression of elements of the Eph/Ephrin system, which might contribute to circadian rhythmicity in biological processes in the brain or peripheral tissues.

Amin, Shaimaa Nasr; Asali, Fida; Aolymat, Iman; Abuquteish, Dua; Abu Al Karsaneh, Ola; El Gazzar, Walaa Bayoumie; Shaltout, Sherif Ahmed; Alabdallat, Yasmeen Jamal; Elberry, Dalia Azmy; Kamar, Samaa Samir; Hosny, Sara Adel; Mehesen, Marwa Nagi; Rashed, Laila Ahmed;

Castelli, Lucia; Galasso, Letizia; Mulè, Antonino; Ciorciari, Andrea; Esposito, Fabio; Roveda, Eliana; Montaruli, Angela

doi: 10.1080/07420528.2023.2241906pmid: 37525628

University students are commonly described as having worsened sleep quality, especially when inactive and Evening-type (E-type) subjects. This study aimed to examine the interactions between physical activity and chronotype on sleep quality among a sample of active Sports Science university students. In November 2019, 433 participants (mean age: 19.7 ± 1.56 years; 70% males) completed the Pittsburgh Sleep Quality Index, the Godin-Shepard Leisure-Time Physical Activity Questionnaire (tertiles categorisation), and the Morningness-Eveningness Questionnaire. Females and E-type slept significantly worse than males and Neither-(N-types) and Morning-types (M-types), respectively. However, there were no significant differences in sleep quality based on physical activity levels. The three-way ANOVA revealed that sleep quality in N- and E-types appeared to be independent of physical activity, whereas M-types showed an improvement in sleep classification with increased physical activity. Moderation analysis indicated that physical activity significantly moderated the relationship between chronotypes and sleep quality. Specifically, M-types demonstrated a more pronounced improvement in sleep quality with increasing physical activity compared to the other chronotypes. In conclusion, M-type university students derived the greatest benefits from physical activity in improving sleep quality. Conversely, physical activity seemed to have a limited impact on sleep quality among active E-type university students.

Saggi, Manjeet Kaur; Phillips, Craig L.; Comas, Maria; Hoyos, Camilla M.; Marshall, Nathaniel S.; Shiao, Judith Shu-Chu; Guo, Yue Leon; Lin, Ting-Ti; Cayanan, Elizabeth A.; Gordon, Christopher J.

doi: 10.1080/07420528.2023.2246559pmid: 37599382

Shift workers are at increased risk of obesity and metabolic diseases, but their eating patterns on work and non-workdays are understudied. We aimed to examine whether energy intake and macronutrient intake of day and night shift nurses were different during work and non-workdays. We used a mixed-methods approach to study food intake of shift working nurses from two hospitals during day and night shifts. Participants completed baseline questionnaires about eating behaviour, sleep, chronotype, mood and shift work disorder. Participants then completed a 4-d food diary which included a non-workday prior to the first shift, the first and last shift (either day or night) and the following non-workday. After completion of the food diaries, we used semi-structured interviews to explore the qualitative aspects of eating behaviours. Seventy-nine shift-working nurses participated in the study. Daily energy intake was not significantly different on work and non-workdays in day or night shift workers (p > 0.05). Whilst macronutrient consumption was also not different between day and night shift workers (p > 0.05), sugar intake was higher in day compared to night shift workers (p = 0.02) on the non-workday prior to the first workday. In qualitative interviews, participants reported their eating to be different on day and night shifts as well as work and non-workdays. Eating behaviour in day and night shift workers was highly influenced by food availability, convenience, peers, and family members. Nurses qualitatively report that night and day shifts result in them eating differently despite no statistically discernible difference in energy intake.

Çelikkol Sadiç, Çağla; Gerçek, Hacer Gizem; Kara, Aziz; Özkan, Yekta

doi: 10.1080/07420528.2023.2249557pmid: 37638644

This study aims to compare adolescents newly diagnosed with major depressive disorder (MDD) and healthy controls in terms of problematic internet use (PIU) and sleep quality. The study sample consisted of 50 newly diagnosed MDD patients aged 12–18 years and 50 healthy controls. Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL) was administered to all cases by a child psychiatrist and sociodemographic data were collected. Children’s Depression Inventory (CDI), Pittsburgh Sleep Quality Index (PSQI), and Internet Addiction Test (IAT) were administered to all participants. Data of the MDD and control groups were compared using Student’s t-test or Mann-Whitney U test and the total scores of the IAT (z = −6.23, p < 0.001) and PSQI (t =–11.42, p < 0.001) scales were found to be significantly higher in MDD cases compared to the control group. The results of analysis of covariance demonstrated that there was a significant positive correlation between CDI and IAT, as well as CDI and PSQI total scores in patients with MDD. While no correlation was observed between the total scores of the IAT and PSQI scales in the MDD group, a significant positive correlation was found between the total scores of the IAT and PSQI scales in the healthy control group. Furthermore, there was a significant difference between the PSQI habitual sleep efficiency subscale score and the IAT total score (r = 0.36, p = 0.009), and the IAT responsibility (r = 0.34, p = 0.015), relationship (r = 0.36, p = 0.01), and mood subscale scores (r = 0.30, p = 0.03). A significant positive correlation was also found between the IAT duration subscale score and PSQI sleep disorder subscale score (r = 0.35, p = 0.013). In addition, binary logistic regression analysis showed that PSQI total score (B = 0.79, p < 0.001) and IAT total scores (B = 0.08, p = 0.001) could be significant predictors of MDD. The findings of this study indicate that the prevalence of PIU and poor sleep quality is higher in adolescents with newly diagnosed MDD compared to healthy controls. The results of our study indicated that the severity of depression, PIU, and sleep quality were significantly correlated in adolescents with newly diagnosed MDD, while PIU and sleep quality were correlated in adolescents without any psychiatric disorders. In addition, this study suggests that poor sleep quality and PIU may be risk factors for MDD.                                   

Xie, Tian; Li, Mingzhu; Hao, Chao; Peng, Yudi; Luo, Wei; Ma, Ning

doi: 10.1080/07420528.2023.2250439pmid: 37605473

Previous research suggested the homeostatic effect on the top-down control system as a major factor for daytime vigilance decrement, yet how it alters the cognitive processes of vigilance remains unclear. Using EEG, the current study measured the vigilance of 28 participants under three states: the morning, the midafternoon after napping and no-nap. The drift-diffusion model was applied to decompose vigilant reaction time into decision and non-decision components. From morning to midafternoon, vigilance declined during sustained wakefulness, but remained stable after midday napping. Increased sleep pressure negatively affected decision time and drift rate, but did not significantly alter the non-decision process. Frontocentral N2 amplitude decreased from morning to no-nap afternoon, associated with slowing decision time. In contrast, parietal P3 had no diurnal alterations during sustained wakefulness, but enhanced after napping. Pre-stimulus parietooccipital alpha power enhanced under high sleep pressure relative to low, accompanied by more lapses in no-nap vs. post-napping conditions. The homeostasis effect is a major contributor to daily vigilance fluctuation, specifically targeting top-down control processes during the pre-stimulus and decision-making stages. Under the influence of sleep homeostasis, the speed of decision-making declines with degradation in target monitoring from morning to afternoon, leading to post-noon vigilance decrement.

Marilac Soalheiro, Luisa; de Jesus Brandão, Beatriz; Paiva, Rafaella Valete Nunes; Dias Carvalho, Lázaro; Menezes Paranhos, Rita deCássia; Ribeiro Barbosa, Paulo César; Guerrero-Vargas, Natali N.; Tamura, Eduardo Koji

doi: 10.1080/07420528.2023.2250870pmid:

Braunstein, S.; Bennett, NC; Voigt, C; Oosthuizen, MK

doi: 10.1080/07420528.2023.2253298pmid: 37667495

The Cape mole-rat (Georychus capensis) is a solitary, strictly subterranean rodent that is responsive to light and entrains to photic cues despite having a reduced visual system. Circadian entrainment is maintained throughout life, but age can alter the amplitude of the response and re-entrainment time. Mole-rats are long-lived for their size which raises questions regarding the robustness of their circadian rhythms and how impacts their locomotor activity rhythms. The locomotor activity rhythms of juvenile and adult Cape mole-rats were investigated. They were exposed to pre-experimental and post-experimental control cycles under fluorescent lights, six 12 h light:12 h dark cycles of decreasing intensities and a constant dark cycle (DD). All animals exhibited more activity during the dark phases of all light regimes. Juveniles were more active than adults and displayed more variable activity during both the light and dark phases. Adults exhibited relatively stable levels of activity under all experimental conditions, whereas juvenile activity decreased as the light intensity was reduced. The amplitude of Cape mole-rat rhythms was consistently low, but similar across light regimes and between adults and juveniles. Cape mole-rats have functional circadian systems, are primarily nocturnal and respond differentially to light intensity depending on their age. Light intensity does not affect the locomotor activity responses of Cape mole-rats in a predictable manner, and could indicate more complex interactions with light wavelengths. The circadian systems of juveniles appear to be more sensitive than those of adults, although the mechanism of the light response remains unclear.

Jung, Jieun; Kang, Jiseung; Kim, Tae

doi: 10.1080/07420528.2023.2253299pmid: 37661839

The link between vitamin D deficiency (VDD) and sleep disturbances has long been suggested. However, the direct causality between VDD, sleep disturbances, and circadian rhythm remains unclear. We aimed to characterize sleep-wake behavior and circadian rhythms in an animal model of VDD. VDD was induced by feeding vitamin D-deficient chow, and we analyzed sleep and circadian rhythm parameters. During light period, VDD mice exhibited reduced wake with more frequent wake bouts and increased NREM sleep time. However, during dark period, the wake EEG power spectrum peaked at theta band frequency, and slow-wave energy was suppressed in mice with VDD. Rest-activity analyses revealed increased circadian period, lower wheel counts, and more frequent and short activity bouts during VDD. Combining sleep and circadian data, we found significantly suppressed activities during the hours with a wake duration shorter than 30 minutes. Moreover, mice in VDD state exhibited a negative correlation between wake theta power and hourly wheel-running counts during dark period. Our data point to a direct link between VDD and disturbances in sleep and rest-activity circadian rhythm, featuring frequent wake bouts during the sleeping phase, reduced sleep pressure build-up in dark period, and reduced activity levels due to increased susceptibility to sleepiness.