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Feb 2024 DOI 10.14302/issn.2574-4518.jsdr-24-4922
D'Angelo MartinaCorresponding author
A state‑of‑the‑science review links the endocannabinoid system to circadian regulation and sleep physiology, examining therapeutic prospects and research gaps.
Apr 2020 DOI 10.14302/issn.2574-4518.jsdr-20-3161
Sedky KarimCorresponding author
Psychiatry Residency Director and Medical Student Education Director, Cooper Medical School of Rowan University
Delayed sleep phase syndrome (DSPS) is a circadian rhythm disorder where individuals experience difficulty modifying the time they go to sleep and wake up in response to environmental changes. The circadian rhythm itself is regulated by a variety of clock genes, and various other genes (e.g., AA-NAT gene, CKIϵ gene) code for proteins that regulate clock genes. Various polymorphisms of the clock gene influencers have been shown to increase susceptibility to DSPS. This paper seeks to examine how certain cultural characteristics (e.g., napping, timing of meals, exposure to artificial light) and the presence of the AA-NAT gene (G619A polymorphism) and the CKIϵ gene (S408N polymorphism) influence the prevalence of DSPS amongst Japanese and Brazilian populations.
Dec 2018 DOI 10.14302/issn.2578-8590.ipj-18-2524
Crespi FrancescoCorresponding author
Biology, GSK Verona, Italy
The pineal gland constitutes a major neuroendocrine organ in the brain. By mean of its neurohormone melatonin it transduces exogenous signals such as circadian and seasonal variations of light and temperature into proper hormonal changes which adjust and adapt internal endocrine functions. Alteration of circadian rhythms has been associated with affective disorders, psychosomatic diseases and cancer. It has been observed that light deprivation, which stimulates (the enzymes responsible for) melatonin production in the pineal, enhances the animal's ethanol preference. Similarly, administration of the pineal hormone to rats maintained under normal conditions of constant photoperiod also induced ethanol drinking. Our hypothesis is that in normal conditions melatonin might be acting as a cerebral "pacemaker", sensitive to endogenous as well as exogenous stimuli in the attempt to maintain an equilibrate circadian interaction between the cerebral activities of endogenous aminergic and opiates systems. Abnormal states (i.e. drug abuse) could result in altered pineal activity, then in rhythmically altered functions of cerebral opiates and/or monoamine neurotransmitters. This may led to the development of a “reward - urge for drug rhythm” resulting in craving, ending in addiction.
May 2018 DOI 10.14302/issn.2574-4518.jsdr-18-2065
Desjardins SophieCorresponding author
Department of Psychology, Universite du Quebec a Trois-Rivieres, Canada.
Objective: Examining the correlation between physical activity measures and sleep in normal adolescents and adult population. Methods: A systematic review was conducted on the effects of exercise, its intensity, its frequency and its timing and sleep outcome. Using the databases including MEDLINE, PsycINFO and SPORTDiscus, keywords used were “sleep”, “circadian rhythm”, “exercise”, and “physical activity”. Results: To improve the general quality of sleep amongst adolescents and adults, individuals should engage in physical activity at any time of day. It also appears very advantageous to engage in long-term physical activity to maintain the positive effects on sleep. Nonetheless, it seems that sedentary individuals can also benefit from occasional physical activity to improve the quality of their subsequent sleep period. Conclusion: A virtuous relationship between physical activity and sleep may exist in normal adolescents and adults. People should seek to benefit from this link to improve both the quality of their sleep and of their daily functioning. However, larger scale studies, controlling for variables might help to better delineated this relationship.
Apr 2018 DOI 10.14302/issn.2578-8590.ipj-18-2078
Kakitsuba NaoshiCorresponding author
Department of Environment and Technology, School of Science and Technology, Meijo University, Nagoya, Japan
Background: The core interthreshold zone (CIZ) is defined as the range between core temperature (Tc) at the onset of shivering and the Tc at the onset of sweating under consistent mean skin temperatures of 28°C to 30°C. A previous study demonstrated a diurnal change in the CIZ for male subjects and its relationship to the cutaneous sensation threshold zone (CSZ). In the present study, diurnal changes in the CIZ and the CSZ for young Japanese female subjects were investigated using the same experimental protocol from the study of male subjects and the sex differences in these responses were then examined. Methods: The CIZ and the CSZ were measured in 10 female subjects who participated in three experiments in a single day during the morning, afternoon, and evening in the summer of 2014 (single-day experiment), and six female subjects who participated in the same experiments on the morning of day 1, the afternoon of day 2, and the evening of day 3 during the summer of 2016 (multiple-day experiment). Air temperature was controlled at 25°C. Each subject wore a suit perfused with 25°C water at a rate of 600 cc/min, and exercised at 50% of their maximum work rate on an ergometer for 10–15 min until their sweating rate increased. They then remained seated, without exercising, until their oxygen uptake increased. Rectal temperature, skin temperature at seven sites, the forehead-sweating rate, and oxygen uptake were continuously monitored throughout the experiment. Cutaneous warm and cold sensation thresholds were measured at three sites using 1-cm2 and 2-cm2 probes. Results: The results from the single-day experiment demonstrated that the CIZ was proportional to core temperature prior to exercise (Tc-init) whereas the results from the multiple-day experiment demonstrated that the CIZ increased continuously from morning to evening despite almost a constant Tc-init. The CIZ appeared to be proportional to the CSZ measured with the 2-cm2 probe. When compared with the results from the previous study of men, no significant sex difference was observed between the CIZ of 0.25±0.07°C for female subjects and 0.21±0.05°C for male subjects. Conclusion: No significant sex difference or diurnal variation in the CIZ was confirmed. Continuous increase in the CIZ from morning until evening is expected in both men and women under a normal Tc circadian rhythm.
May 2016 DOI 10.14302/issn.2574-450X.jom-16-1039
V. Seeman MaryCorresponding author
Professor Emerita, Department of Psychiatry, University of Toronto, 260 Heath St. W., Suite 605, Toronto, Ontario, M5P 3L6, Canada.
Over the last three decades, an epidemic of obesity has markedly affected patients suffering from mental illnesses such as schizophrenia. Antipsychotic medications used to treat schizophrenia are considered as major culprits. The aim of this review is to first consider risk factors, to then outline negative sequelae of obesity for this population, and finally to address timing and content of recommended clinical interventions. Medical databases were searched with the terms “”weight,” “obesity,” and “schizophrenia.” Selection of articles was guided by date of publication; recent papers are preferentially cited. The main findings were that, in addition to antipsychotic medications, socio-economics, lifestyle, immune factors, and circadian rhythms also contribute to obesity risk. A barrier to effective health promotion within psychiatry has been the concern that fears about gaining weight might stop individuals with schizophrenia from taking needed antipsychotic medication. Recommendations, therefore, are to keep the dose of antipsychotic medication as low as possible, avoid polypharmacy, encourage healthy eating and physical activity, address sleep problems and substance use, monitor weight, blood pressure, and metabolic parameters regularly, utilize motivational interviewing techniques and peer support, pay special attention to special needs such as those of women during pregnancy, and include bariatric surgery as a potential intervention. Conclusion: Besides careful attention to medication regimens, the literature supports the active encouragement and support of patient self-management strategies to both prevent and manage obesity in schizophrenia.
Jun 2015 DOI 10.14302/issn.2574-4372.jesr-14-607
E. Geusz MichaelCorresponding author
Bowling Green State University, Dept. of Biological Sciences, Bowling Green, OH 43403
Cancer is influenced by the ability of cells to maintain circadian rhythms in molecular and metabolic processes. Disturbance of the underlying circadian timing mechanism in circadian clock cells leads to a higher frequency and more rapid progression of cancer. Cancer stem cells with properties of embryonic and somatic stem cells have been implicated as tumor initiators in several types of cancers. Although tumors are reported to have disorganized circadian rhythms, evidence of in vitro circadian rhythms in cancer stem cells of gliomas was recently presented. The possibility and consequences of circadian clocks functioning in cancer stem cells within tumors is examined, and the possible benefits to these cells from circadian timing is discussed in relation to cancer treatments.