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Objective: To investigate the effect of melatonin and/or diazepam on the endogenous rhythm in cultured myocardiocytes and in that connexion to inquire into the mechanism of circadian oscillation level.
Methods: The beating rate of cultured myocardiocytes was dynamically monitored by an inverted phase-contrast microscope coupled to high speed CCD camera and computer system. Under the culturing condition of artificial light L:D = 12:12, the circadian rhythm variation of cultured myocardiocytes beating frequencies was measured, and then the effect exerted by melatonin and/or diazepam on that circadian rhythm was studied.
Results: It was found that under the L:D = 12:12 culturing condition, the cultured myocardiocytes exhibited prominent circadian rhythm. With the use of melatonin and or diazepam, the circadian rhythm of those myocardiocytes changed, not only the amplitude and mesor decreased, but also the acrophase delayed.
Conclusion: The modulation of circadian rhythm in cellular level is not only related with endogenous control but also affected by external factors.
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Biol Trace Elem Res
September 2025
Department of Occupational and Environmental Health, Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science
The uncharted effects of cadmium and cesium on circadian syndrome (CircS), an emerging circadian rhythm disorder drawing considerable attention, and underlying mechanisms warrant exigent elaboration. Data of 11141 subjects from National Health and Nutrition Examination Survey 2005-2018 were incorporated to investigate separate-, joint-/interaction-, and mixture-effects of urinary cadmium and cesium on prevalent CircS risk exploiting survey weight regression and quantile g-computation. The underlying mechanisms were probed by network toxicological analysis.
View Article and Find Full Text PDFFungal Biol
October 2025
Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA. Electronic address:
In many model organisms, the circadian system has been proposed to comprise multiple oscillators that interact to promote accuracy of the clock as well as intricacies of rhythmic outputs. In Neurospora crassa, the circadian transcriptional/translational loop comprising of the FRQ (Frequency) and WCC (White Collar Complex) proteins has been instrumental in explaining many attributes of the clock including entrainment and rhythms in development and gene expression; in addition, some non-circadian oscillations can be unmasked when the FRQ-WCC feedback loop is eliminated. These rhythms have often lost defining circadian characteristics and are potentially controlled by other oscillators, termed FRQ-less oscillators (FLOs) in Neurospora.
View Article and Find Full Text PDFNeuroscience
September 2025
Nanjing Research Institute of Electronic Technology, Nanjing 210039, China. Electronic address:
Sleep disorders encompass a range of diseases and symptoms that disrupt individual sleep patterns, degrade sleep quality, and diminish sleep efficiency. Currently, the mechanisms governing sleep regulation and the etiology of sleep disorders remain unclear, leading to clinical treatments that are primarily symptomatic due to the absence of precise intervention methods. Recent studies suggest that glymphatic-meningeal lymphatic route is responsible for the clearance of macromolecular metabolites from the brain, thus playing a pivotal role in maintaining sleep homeostasis and circadian rhythm.
View Article and Find Full Text PDFMar Pollut Bull
September 2025
St Abbs Marine Station, The Harbour, St Abbs TD14 5PW, United Kingdom. Electronic address:
The offshore renewable energy industry is expanding rapidly due to decarbonisation commitments and need for energy security. This will change the marine environment in ways that are not fully understood, including more subsea power cables in the sea. Movement of electricity through these cables generates an electromagnetic field (EMF), which might affect marine species.
View Article and Find Full Text PDFMol Nutr Food Res
September 2025
Department of Nutrition and Food Hygiene, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China.
Current research indicates that insulin secretion deficiency in β-cells contributes to Type 2 diabetes mellitus (T2DM), which is associated with neuropeptide Y receptor (Npy1r) overexpression from neuropeptide Y (NPY) system dysregulation. To date, limited literature has explored nobiletin (NOB) as a circadian modulator for restoring β-cell function through Npy1r regulation. This study investigates NOB's stimulatory effects on insulin secretion via Npy1r and clock-modulatory signaling to elucidate its underlying mechanism.
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