Chronobiology International最新文献

Although delay-based shiftwork/jetlag schedules are often considered less disruptive than advances and are increasingly adopted in occupational settings, their long-term impact on physiological homeostasis remains underexplored. In this study, we investigated the consequences of repeated phase delays on circadian alignment, oxidative balance, endocrine function, and systemic inflammation in the diurnal rodent Funambulus pennantii. Animals were kept either under a stable 12:12 hour light-dark (LD) cycle or subjected to a successive delay rotational shift (SDRS) schedule for 28 days. In the SDRS schedule, the light phase was delayed by 8 hours every two days, and every seventh day, animals were returned to the normal LD cycle for rest. SDRS exposure led to marked circadian misalignment, evident from disrupted and desynchronized locomotor activity rhythms. Biochemical analyses revealed reduced serum melatonin and antioxidant enzyme activity (SOD, CAT), along with elevated corticosterone levels, indicating stress induction. Moreover, animals under SDRS showed significant increases in pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), highlighting immune activation. Our results highlight that delay-based shift schedules, often considered less harmful, can significantly impair physiological resilience, warranting a re-evaluation of their perceived safety due to their stress and inflammatory effects in diurnal systems.

Lung cancer remains one of the most fatal cancers, with cigarette smoke (CS) exposure being a major risk factor due to its role in triggering oxidative stress. Disruption of circadian rhythms, increasingly common in modern lifestyles, has also been linked to cancer progression. Targeting both oxidative imbalance and circadian disruption may offer a more effective therapeutic approach. Toluquinol (TQ), a compound derived from marine fungi, has shown promising anti-tumor activity and potential relevance in circadian-based cancer strategies. The current study investigated the role of TQ as a potential circadian medicine in modulating the dysregulated circadian-regulatory gene expression in the CS-exposed NCI-H23 lung adenocarcinoma cell line. Among the core circadian regulatory genes, NR1D1 plays a crucial role as a transcriptional repressor, involved in maintaining the circadian rhythm, regulating redox homeostasis, and modulating inflammation. Dysregulation of NR1D1 has been linked to cancer progression and poor prognosis in lung cancer. This study offers valuable insights into the impact of CS on NR1D1 gene regulation and its role in lung cancer development, which is mediated through disrupted redox balance and inflammation, while highlighting the potential therapeutic role of TQ in mitigating this process.

We aimed to investigate whether bright light (BL) exposure affects sympathovagal activity in controlling heart rate (HR) before and after exercise. Eighteen healthy men (28 ± 4 years) underwent two experimental conditions: one under BL (5000 lux) and another under dim light (DL < 8 lux). In both conditions, subjects performed an aerobic exercise bout (cycle ergometer, 30 min at 50-60% of HRreserve). HR (electrocardiography) and respiratory rate (piezoelectric belt) were initially assessed at baseline light (500 lux). Measurements were repeated before and 10 min after the exercise in both light conditions, BL and DL. Cardiac autonomic modulation was evaluated using spectral analysis of HR variability. Before exercise, DL did not change HR but decreased low- to high-frequency ratio of HR variability (LF/HF_RR, DL = -0.35 ± 0.43 vs. BL = +0.00 ± 0.55, p < 0.01). From pre- to post-exercise, HR increased similarly, while LF/HF_RR increase was greater in DL than BL (+1.12 ± 0.87 vs. +0.60 ± 0.98, p = 0.04). Contrary to our hypothesis, in healthy men, BL did not exacerbate HR and cardiac sympathovagal balance. However, DL exposure decreased pre-exercise cardiac sympathovagal balance, a difference that no longer persisted postexercise.

Light serves as the main synchroniser of the circadian system. The amount of light and its spectral distribution throughout the day influence hormonal secretion and sleep-wake regulation. There is a knowledge gap regarding the impact of the spectrum and intensity reduction of short-wavelength light during the day on circadian system outputs. In the present study, 23 participants spent 5 working days in the reference office with full-spectrum lighting. In the experimental week, participants spent five working days in the office with reduced intensity and short-light spectrum up to 500 nm. We measured melatonin, cortisol, and salivary alpha-amylase (sAA) activity in morning and evening saliva under dim light or light exposure (LE) and sleep by wrist actigraphy. Daylight impacted sleep quality only in females. The melatonin did not differ due to a changed daylight, but the LE had a stronger suppressive effect during the experimental week. The cortisol in the morning was higher in females, with no differences between weeks. To conclude, modified daylight has an impact on sleep quality without significant hormonal or sAA changes. LE before sleep can influence melatonin and sleep quality depending on the previous light history with high interindividual differences.

Circadian dysregulation is implicated in Major Depressive Disorder (MDD). This study investigated the mediating roles of sleep disturbances and somatic symptoms in the circadian preference-depression relationship and explored moderating effects of NPAS2 variants in 257 MDD patients. The Hamilton Rating Scale for Depression (HAMD-17,17-item clinician-rated measure of depression severity), Morningness-Eveningness Questionnaire (MEQ, circadian preference scale), Pittsburgh Sleep Quality Index (PSQI, sleep quality measure), and Depression and Somatic Symptoms Scale (DSSS, somatic symptom inventory) were obtained in all subjects. Genotypes of single nucleotide polymorphisms (SNPs) of NPAS2 were determined by the PCR and MassArray SNP sequencing analysis. Spearman's correlation, bootstrap mediation, and moderated mediation analyses revealed that sleep disturbances and somatic symptoms sequentially mediated the circadian preference-depression link (preference→sleep: β = -0.075,p = 0.002; sleep→somatic: β = 0.711,p < 0.001; somatic→depression: β = 0.216,p < 0.001). NPAS2 variants moderated these effects: rs3768984 strengthened eveningness-sleep associations (β = 2.944,p < 0.05), while rs3811561 showed similar amplification (β = 3.942,p < 0.05). Rs3768984 additionally moderated the mediation pathway (β = -0.054,95%CI[-0.09,-0.02]). These findings elucidate mechanistic pathways connecting circadian rhythms and MDD, highlighting NPAS2 as a genetic moderator, which may inform targeted interventions. Future studies could explore circadian genetic influences on personalized depression interventions.

The African fig fly, Zaprionus indianus, is an invasive pest of global concern, infesting over 80 crop species - including high-value fruits such as figs, strawberries, and guavas - and driving significant economic losses. Its ecological success is closely linked to circadian-regulated mating behavior, which enhances reproductive efficiency and fosters adaptability to diverse environments. Like the popular model organism Drosophila melanogaster, Z. indianus exhibits robust locomotor rhythms. A key feature of the circadian clock is its ability to anticipate predictable events, such as light-dark transitions, by gradually increasing or decreasing activity in advance. Mating rhythm is uniquely synchronized to light cycles: mating peaks show anticipation of both lights-on and lights-off transitions, with lights-off anticipation persisting even under long photoperiods (16-h light:8-h dark), suggesting circadian control. Remarkably, Z. indianus rapidly adapts to simulated jetlag, underscoring its plasticity in shifting environments. A critical distinction from D. melanogaster is its persistently low mating activity under constant darkness, indicating an obligate light dependence for mating. This reliance on light cues, combined with circadian plasticity and rapid environmental acclimation, likely underpins its capacity to colonize ecologically diverse regions and expand its geographic range. These insights into Z. indianus's mating rhythm not only advance understanding of its invasive success but also offer actionable targets for disrupting its reproductive cycles, informing strategies to curb its spread and mitigate agricultural damage.

This study examines how dietary nutrient patterns vary among individuals with different chronotypes. In other words, this research explores the potential connections between nutrient intake and circadian rhythm. In this secondary data analysis, we used data from 3,072 adult participants (mean age: 30.16 y (SD = 10.92); 49.8% males) who completed a survey between September 2022 and July 2023. Chronotypes were assessed using the Morningness-Eveningness Questionnaire (MEQ), and dietary intake was measured through 24-h dietary recall. One-way ANOVA and Multinomial regression analysis were used to investigate the associations. The intermediate chronotype was the most common among participants (73% vs 13% early and 14% late chronotype). Unlike morning types, intermediate and evening chronotypes had similar demographic and dietary characteristics. Four nutrient patterns were identified: "Vit B-rich," "Plant-based," "Antioxidant," and "High-fat." "Vit B-rich pattern" was linked to a morning chronotype. Greater adherence to the "antioxidant pattern," characterized by nutrients such as vit A, vit C, and folate, was associated with a lower likelihood of being an evening type. Adherers of "high-fat pattern" were less likely to be intermediate types. "Plant-based" pattern characterized by fibre, magnesium, etc. was not associated with any chronotype. Morning chronotypes may gravitate toward or consume more foods rich in vit B. People with an intermediate chronotype may be less likely to follow a "high-fat" diet, and evening types may be less likely to follow an "antioxidant" diet. Longitudinal studies are needed to clarify the direction of the relationship between chronotype and dietary intake.

Therapy with local anesthetics (TLA) is known to provide long-lasting pain relief, raising the question of whether these effects are mediated by changes in autonomic nervous system (ANS) regulation. To address this, we examined alterations in 24-h heart rate variability (HRV) following TLA treatment. Twenty-four patients undergoing TLA and 11 controls were monitored with Holter-ECG over 24 h. HRV parameters including mean heart rate (HR), root mean square of successive differences (RMSSD), stress index (SI), low- and high-frequency power, and total power were calculated in 15-min epochs. Changes were analyzed separately for the day and subsequent night, and the standard deviation of change between consecutive 15-min intervals was introduced as an additional parameter. TLA was associated with significant shifts in HRV within 24 h: HR and SI decreased, whereas RMSSD and low-frequency power increased, with effects most pronounced during the night. Moreover, the variability of changes between epochs was reduced across several parameters, particularly HR, RMSSD, and SI, suggesting a "smoothing" effect in HRV dynamics. These findings indicate that 24-h HRV monitoring can capture autonomic effects of TLA beyond its immediate analgesic action. The reduction of variability in HRV changes introduces a novel metric for assessing ANS modulation, offering new insight into the mechanisms and therapeutic potential of TLA.

This study compared screen time, circadian rhythm patterns, and sleep quality in adults diagnosed with attention-deficit/hyperactivity disorder (ADHD) and healthy controls, and examined the associations among these parameters. The sample included 100 adults with ADHD and 100 healthy controls. Participants were assessed using a sociodemographic data form, the Diagnostic Interview for ADHD in Adults (DIVA 2.0), the Structured Clinical Interview for DSM-5 Disorders (SCID-5-CV), the Adult ADHD Self-Report Scale (ASRS), the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN), the Pittsburgh Sleep Quality Index (PSQI), and the Screen Exposure Questionnaire. All instruments except the DIVA 2.0 were administered to controls. Adults with ADHD reported significantly longer total daily screen time than controls (p < 0.001) and exhibited higher ASRS, BRIAN, and PSQI scores (all p < 0.001) In both groups, screen time was positively correlated with BRIAN and PSQI scores. Hierarchical regression analysis indicated that biological rhythm disruption (BRIAN scores) was a stronger predictor of poor sleep quality (PSQI scores) than ADHD symptom severity or screen time (p < 0.001)). Overall, adults with ADHD demonstrated greater screen exposure, more disrupted circadian rhythms, and poorer sleep quality compared to controls. Across the full sample, biological rhythm disruption emerged as the most robust predictor of impaired sleep, underscoring its potential clinical relevance for addressing sleep disturbances in adults with ADHD.

The objective of this study was to unveil the interplay between circadian rhythms (CR) and hypertensive nephropathy (HTN) by investigating genes, pathways, and molecular functions and the correlation between CR and HTN's immune landscape through bioinformatic approaches. Key genes associated with CR in HTN were screened through an integrated analysis of GEO data, employing consensus clustering and machine learning approaches (Generalized Linear Models (GLM), Random Forest (RF), and Support Vector Machine (SVM)). CIBERSORT, ESTIMATE and ssGSEA algorithm were used to assess the infiltration of immune cells between HTN and control groups and in three distinct CR phenotypes of HTN. Functional analyses including GO and KEGG were conducted to elucidate the underlying mechanisms. The DGIdb website is utilized for predicting potential effective therapeutic drugs targeting CR genes closely linked to HTN. We obtained 45 differentially expressed CR-related genes and these genes are mainly involving signaling pathways such as rhythmic process, circadian rhythm and TGF-beta signaling pathway. Three CR related genes (CCL5, ATF3 and NR4A1) were identified to construct a diagnostic model and have a good performance in diagnosis of HTN and patients with HTN were clustered into three subgroups by consensus clustering according to these genes. Analysis of immune infiltration revealed immune heterogeneity between HTN patients and controls and between the three key CR-related gene clusters of patients with HTN. Furthermore, three CR related genes clusters revealing distinct ESTIMATE Score, Immune Score, Stromal Score heterogeneity with p value < 0.05. Meanwhile, spearman analysis showed CCL5 has a strong correlation different immune cells infiltration, especially NK activated cells (p < 0.001), ATF3 has a correlation with NK resting cells (p = 0.029) and NR4A1 has the most significant correlation with activated T CD4 memory cells infiltration (p = 0.020). The potential therapeutic drug predictions for three CR genes indicate that ATF3 and NR4A1 may harbor potential effective treatment options. Our findings suggest an association between circadian rhythm disruption and altered immune landscape in HTN, highlighting the potential role of CR-related genes in disease heterogeneity. The genes CCL5, ATF3, and NR4A1-which are implicated in circadian regulatory networks - may serve as candidate biomarkers and provide new directions for diagnostic and therapeutic strategies in HTN. Further experimental validation is required to confirm their functional roles and clinical significance .