Chronobiology International最新文献

{"title":"Environmental circadian disruption alters rhythmicity of clock and epigenetic gene expression in SKH-1 female mouse livers.","authors":"Rachel Bernstein, Venugopal R Bovilla, Sean J Cone, Tusha Sharma, Cathrine Hoyo, Shobhan Gaddameedhi","doi":"10.1080/07420528.2026.2732184","DOIUrl":"https://doi.org/10.1080/07420528.2026.2732184","url":null,"abstract":"<p><p>Endogenous circadian rhythms are primarily entrained by environmental cues that are used to regulate the function of cells and peripheral tissues throughout the body. We found that disrupted light schedules - reflective of shift work conditions - demonstrated impaired gene expression throughout the 24-h day in core clock and epigenetically regulated genes. Dysregulated expression in these genes has been independently detected in the etiology of sleep-related diseases, suggesting epigenetic regulation as a potential mechanistic link between circadian disruption and health outcomes. Because of this, we hypothesized that epigenetic regulatory factors are circadian expressed and can be dysregulated by environmental circadian disruption. In this study, we show rhythmic expression of both core clock and epigenetic genes in female SKH-1 mouse livers under normal circadian conditions and the subsequent effect of disrupted clocks thereafter. To address our hypothesis, we measured relative gene expression patterns in female mouse livers under healthy and disrupted clock conditions. In 5 of the 8 core clock genes (<i>Cry1, Cry2, Npas2, Nr1d1, Per2</i>), there was a significant loss of rhythmic expression. All active demethylases and <i>Zfp57</i> experienced a loss of rhythmicity due to clock disruption, while both <i>de novo</i> DNMTs, <i>Dnmt3a</i> and <i>Dnmt3b</i>, displayed a slight damping of rhythmicity in disrupted clock mice.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1-16"},"PeriodicalIF":2.5,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149104966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Melatonin as a daily rhythm control signal for glucose homeostasis and insulin secretion in horses.","authors":"Claudia Giannetto, Maria Rizzo, Caterina Faggio, Giulia Sisia, Elisabetta Giudice, Alessandro Attanzio, Giuseppe Piccione, Francesca Arfuso","doi":"10.1080/07420528.2026.2744436","DOIUrl":"https://doi.org/10.1080/07420528.2026.2744436","url":null,"abstract":"<p><p>An involvement of melatonin in the regulation of glucose homeostasis and insulin secretion in pancreatic β-cells has been proposed. To evaluate the features of the daily rhythms of plasma melatonin, blood glucose, and insulin in horses, ten clinically healthy Italian Saddle geldings, 9-10 years old with a mean body weight of 490 ± 25 kg, were enrolled. The animals were housed in individual boxes under natural environmental conditions (sunrise 06:10; sunset 18:10; 12-15°C, 77% RH). All horses were cannulated the day before the start of the study for sample collection, which was performed every 4 h for a 48-h period. Blood samples were analysed for melatonin, glucose, and insulin concentrations. Our results showed higher melatonin serum concentration and lower glucose concentration during the dark phase than the light phase. All investigated parameters showed a daily rhythm during the 2 d of monitoring. Melatonin acrophase was observed in the dark phase, glucose acrophase in the light phase, and insulin acrophase nearest the sunset. A negative correlation was observed between glucose and melatonin, and a positive correlation was observed between insulin and the other two parameters.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1-9"},"PeriodicalIF":2.5,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149104989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clockwork symbiosis: The vital interplay of microbiota and human chronobiology.","authors":"Fadia Boubaker, Omkolthoum Sallem, Ichrak Dridi, Anis Chabbou","doi":"10.1080/07420528.2026.2682478","DOIUrl":"10.1080/07420528.2026.2682478","url":null,"abstract":"<p><p>The human microbiota and host circadian system engage in a bidirectional dialogue with consequences for metabolism, immunity, and barrier physiology. This narrative review examines the microbiota-chronobiology interface across the gut and selected extra-intestinal niches and uses the term \"clockwork symbiosis\" as an organizing framework for this crosstalk. A structured, non-exhaustive search of PubMed, Scopus, Web of Science, Cochrane Library, and Embase was conducted for studies published between 2000 and 2024, with priority given to human evidence and mechanistic studies with clear translational relevance. The strongest evidence concerns the gut microbiota, for which both human and preclinical studies support diurnal variation in microbial composition, metabolite production, and host metabolic signaling. By contrast, evidence for vaginal, oral, skin, and respiratory microbiota remains comparatively limited and is best treated as emerging and largely hypothesis-generating. Across the literature, circadian disruption is associated with altered microbial rhythmicity and adverse metabolic or inflammatory phenotypes, but causality is often difficult to isolate from co-occurring changes in diet, sleep, stress, light exposure, medication use, and host disease state. Microbiota-derived metabolites, particularly short-chain fatty acids and bile-acid derivatives, provide plausible mechanistic links to peripheral clocks, although evidence for direct clinical manipulation remains preliminary. Overall, preserving host-microbiota temporal alignment appears biologically important, but clinical applications such as chrononutrition, timed biotics, and chronotherapy still require rigorous time-standardized human studies.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1484-1492"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148155523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A cacao by-product ingredient prevents locomotor circadian disruption due to high-fat diet administration by regulating clock genes.","authors":"Dafne Velásquez-Jiménez, Manuel Miranda-Anaya, Ramón Gerardo Guevara-González, Rocio Campos-Vega","doi":"10.1080/07420528.2026.2686761","DOIUrl":"10.1080/07420528.2026.2686761","url":null,"abstract":"<p><p>Cacao by-products are frequently discarded as waste despite representing a sustainable source of bioactive compounds, including dietary fiber and phenolic constituents. A cacao by-product ingredient (CBI), designed based on in silico predictions, has been proposed to contain components capable of modulating core clock proteins. Although high-fat diets (HFD) are known to disrupt circadian organization, the potential of CBI to counteract HFD-induced circadian alterations remains unexplored. This study aimed to evaluate the effects of CBI on circadian disruption induced by HFD consumption. Four experimental diets (STD, STD +6% CBI, HFD, and HFD +6% CBI) were formulated and characterized for their chemical, nutraceutical, and bioactive composition. Mice were fed ad libitum and maintained under a 12:12 h light-dark cycle (LD 12:12 h) for ten weeks, followed by two weeks in constant darkness (DD) and subsequent re-entrainment to LD 12:12 h. At the end of the protocol, animals were euthanized at ZT6 and ZT18 to assess the expression of the core clock genes Bmal1 and Per2 in the hypothalamus, liver, adipose tissue, and ileum; hepatic PPARα expression was also evaluated. Nutritional analyses showed that CBI enrichment significantly increased dietary fiber content and enhanced the phenolic profile. Behaviorally, HFD increased locomotor activity during the mid-day, shortened ultradian cycles, delayed activity onset, and lengthened the free-running circadian period under DD conditions. HFD also significantly altered the day/night expression profiles of clock genes across the tissues analyzed. Notably, CBI supplementation partially reversed these alterations in an organ-dependent manner, restoring free-running period and clock-gene expression patterns toward STD-like levels. These findings suggest for the first time that CBI, a functional ingredient designed from discarded cacao by-products, effectively may be mitigating HFD-induced circadian desynchronization This work highlights both the potential valorization of agricultural waste and a promising nutritional strategy to support metabolic and circadian health through modulation of central and peripheral clocks.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1710-1724"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148257545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal and daylight saving time-related variation in hydroxyzine prescribing: Evidence of circadian and environmental modulation in primary care.","authors":"Małgorzata Romaszko, Katarzyna Glińska-Lewczuk, Aleksandra Kocbach-Przudzik, Michał Majewski","doi":"10.1080/07420528.2026.2682479","DOIUrl":"10.1080/07420528.2026.2682479","url":null,"abstract":"<p><p>Hydroxyzine is commonly used off-label as a hypnotic medication because of its sedative properties. The available data on hydroxyzine use in primary healthcare are limited, and the impact of seasonal factors on its prescribing has not been investigated. This study examined whether environmental photoperiod and circadian misalignment related to daylight saving time (DST) transitions modulate hydroxyzine prescribing patterns in primary care. A retrospective analysis was conducted, covering 13 625 medical consultations provided to adult patients (≥18 y of age) at a primary healthcare centre in Olsztyn, Poland, between 2012 and 2024. Prescriptions for medications containing hydroxyzine were identified using the ATC classification (N05BB) and analysed by season, sex, and periods before and after the spring and autumn DST transitions. After adjustment for the number of patients registered at the centre, women were prescribed hydroxyzine 2.76 times more often than men. A significant seasonal prescribing pattern was observed. In both women and men, the average daily number of prescriptions was highest in winter and lowest in summer. The relative winter - summer increase was 11.4% in women and 37.5% in men. DST transitions were not associated with any measurable change in hydroxyzine prescribing. Hydroxyzine prescribing in primary healthcare showed a clear seasonal pattern and marked sex-related differences. These findings may suggest frequent use of hydroxyzine for sedative, anxiolytic, or sleep-promoting purposes, whereas DST transitions did not appear to affect prescribing patterns.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1642-1650"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148148772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brain rot in the digital age: Sleep loss, circadian disruption, and neurocognitive vulnerability.","authors":"Fatih Ekici, Muhammet Cahit Atılgan, Samet Kaya, Yavuz Selvi","doi":"10.1080/07420528.2026.2686763","DOIUrl":"10.1080/07420528.2026.2686763","url":null,"abstract":"<p><p>The colloquial expression \"brain rot\" is increasingly used to describe attentional fragmentation, cognitive fatigue, motivational blunting, and a sense of mental \"slowness\" after prolonged engagement with high-intensity digital media. In this semi-structured narrative review, we use the term as a heuristic bridge concept rather than a formal diagnosis and examine whether sleep and circadian mechanisms provide a biologically coherent account of these complaints. PubMed and Google Scholar were searched through March 2026, with emphasis on chronobiology, sleep deprivation/restriction, digital media use, reward-heavy platforms, media multitasking, and adolescent development. The strongest direct human evidence supports a proximal pathway from evening or post-bedtime digital exposure to sleep displacement, melatonin suppression, circadian delay, shortened sleep, and next-day attentional and emotional dysregulation. We then review candidate downstream mechanisms involving synaptic homeostasis, cortical excitation-inhibition balance, thalamocortical oscillations, large-scale network instability, and reward-related behavior. By contrast, evidence linking typical digital-media-associated partial sleep restriction to amyloid or tau accumulation remains indirect and should not be interpreted as proof of neurodegeneration. Overall, \"brain rot\" is best conceptualized as a sleep- and circadian-linked neurocognitive vulnerability state, with particularly high relevance to adolescents and young adults because of developmental phase-delay biology, ongoing maturation of prefrontal executive control, and environmental timing pressures.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1508-1517"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148210225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of circadian rhythm disruption on biochemical parameters in mice.","authors":"Humaira Umer, Tamseela Mumtaz, Ralf Weiskirchen, Sumaira Aslam, Faiza Ambreen","doi":"10.1080/07420528.2026.2681614","DOIUrl":"10.1080/07420528.2026.2681614","url":null,"abstract":"<p><p>Disruption of circadian rhythm is common in rotating shift workers, individuals with jet lag, and people with irregular sleep schedules and contributes to metabolic diseases including obesity, type 2 diabetes, metabolic dysfunction-associated steatotic liver disease, and hepatocellular carcinoma. To delineate early metabolic consequences of circadian disruption, we examined glucose, iron, and lipid homeostasis in a murine model of chronic jet lag. Mice were exposed to a validated protocol in which the light cycle was advanced by 8 hours every 2 days, and blood was collected at four Zeitgeber times (ZT0, ZT6, ZT12, ZT18). Jet-lagged mice displayed a progressive rise in random blood glucose toward the dark phase, whereas controls remained within the normal range with a distinct circadian pattern (<i>p</i> < 0.05), suggesting altered glucose regulation across day and night. Serum iron remained within normal limits and showed only minor circadian variation compared with controls (<i>p</i> < 0.05), indicating largely preserved iron homeostasis. In contrast, lipid metabolism was profoundly altered. Total cholesterol and triglycerides were significantly higher and exhibited phase-shifted rhythms, with exaggerated nocturnal peaks and light-phase elevations. HDL levels were consistently reduced, while LDL/VLDL showed marked increase in concentration (all <i>p</i> < 0.05). These patterns are consistent with disturbed hepatic lipid synthesis, export, and peripheral uptake and with increased nocturnal lipid mobilization. Correlation analysis revealed moderate positive associations of glucose with triglycerides and VLDL, a strong correlation between cholesterol and LDL, and a strong inverse correlation between triglycerides and HDL, whereas iron showed only weak relationships with metabolic traits. Together, these data indicate that chronic circadian misalignment preferentially disrupts coordinated glucose and lipid metabolism while iron levels showed modest variations, consistent with early metabolic alterations associated with circadian disruption.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1609-1623"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148155573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multivariate associations between sleep patterns and self-regulation in adolescence: Canonical correlation analysis across ABCD and NCANDA cohorts.","authors":"Tommy Gunawan, Ty Brumback, Brant P Hasler, Qingyu Zhao, Susan F Tapert, Alejandro D Meruelo","doi":"10.1080/07420528.2026.2685032","DOIUrl":"10.1080/07420528.2026.2685032","url":null,"abstract":"<p><p>Adolescence involves pronounced changes in sleep timing and duration that have been linked to executive functioning, impulsivity, and risk behaviors, yet evidence for generalizable sleep - self-regulation associations remains limited. We used regularized canonical correlation analysis to examine multivariate relationships between sleep and self-regulation across two independent cohorts. In the Adolescent Brain Cognitive Development study (<i>n</i> = 11,143), later chronotype and shorter sleep duration were associated with higher impulsivity, particularly urgency and deficits in planning and perseverance (<i>r</i> = 0.21, permutation <i>p</i> < 0.001), with minimal contribution from delay discounting. Social jetlag showed weak loadings. In the National Consortium on Alcohol and Neurodevelopment in Adolescence cohort (<i>n</i> = 831), only one canonical function was statistically significant (<i>r</i> = 0.15, <i>p</i> = 0.011), characterized by later chronotype and greater social jetlag, with minimal contribution from sleep duration and primary loadings on impulsivity-related measures. Applying the ABCD-derived sleep - self-regulation pattern to NCANDA produced a small but nonzero association, driven primarily by social jetlag and delayed sleep timing, with minimal influence of sleep duration. These findings provide multivariate evidence linking delayed sleep timing and circadian misalignment to adolescent self-regulation, though effect sizes attenuate across cohorts. Longitudinal work is needed to clarify predictive pathways and inform sleep-focused interventions during this vulnerable developmental period.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1661-1675"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13455002/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148359653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heart rate variability and heart rate fragmentation among shift workers: The Multi-Ethnic Study of Atherosclerosis.","authors":"Mussammat Snigdha Sowrin, Ana Espinosa, Susan R Heckbert, Susan Redline, Gerben Hulsegge, Barbara N Harding","doi":"10.1080/07420528.2026.2679138","DOIUrl":"10.1080/07420528.2026.2679138","url":null,"abstract":"<p><p>Night shift work is linked with cardiovascular disease (CVD), although underlying mechanisms remain unclear. Heart rate variability (HRV) is a well-established biomarker, but heart rate fragmentation (HRF) may offer additional insights. We conducted a study to compare heart rate metrics, including HRV and HRF, across different types of shift schedules, and to evaluate the influence of sleep duration. In this cross-sectional study, we included 845 participants (mean age 64; 51% women) from the Multi-Ethnic Study of Atherosclerosis Sleep study. Heart rate metrics were compared between the day shift (reference), night/rotating shift, and other shift workers using adjusted linear regression. HRV was measured from overnight bipolar (Electrocardiogram) ECG. HRV (log transformed) and HRF values were reported as % difference with 95% confidence intervals (CIs). Analyses were stratified by sleep duration (short <7 h, recommended 7-<9 h, and long ≥9 h), and tested for interaction. Night/rotating shift workers had higher HRF than day shift workers, particularly a greater percentage of normal-to-normal intervals in alternation segments (PAS) (% difference 11.9, 95% CI 1.8, 22.0). We found differences based on sleep duration for PAS. The difference was most pronounced in workers with short sleep (% difference 20.4, 95% CI 3.0 to 37.9), somewhat smaller in those with recommended sleep (% difference 14.2, 95% CI -1.0 to 29.5), and reversed in long sleepers (% difference -10.8, 95% CI -32.4 to 10.8; interaction <i>p</i> = 0.06) Interaction terms were assessed at <i>p</i> < 0.10. HRV metrics showed minimal differences and no consistent patterns across shift groups. Night shift work is related to higher HRF, and sleep duration influences these findings, which may reflect circadian misalignment and autonomic dysregulation.</p>","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"1600-1608"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148315998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction.","authors":"","doi":"10.1080/07420528.2026.2685905","DOIUrl":"10.1080/07420528.2026.2685905","url":null,"abstract":"","PeriodicalId":10294,"journal":{"name":"Chronobiology International","volume":" ","pages":"I-III"},"PeriodicalIF":2.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148210299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}