Journal articles: 'Circadian strategies'

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Kalmukova, Olesia, Vitalii Kyryk, and Mykola Dzerzhynsky. "CIRCADIAN RHYTHMS AND PERSONALIZED STRATEGIES FOR ANTI-AGING THERAPIES." Anti-Aging Eastern Europe 1, no. 1 (June 28, 2022): 19–27. http://dx.doi.org/10.56543/aaeeu.2022.1.1.03.

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Background. Nowadays personalized medicine is actively developing and consists of individual approaches during patients' treatment, diagnoses and prognoses. Since the first use of DNA sequence analysis in 2009, many other directions and methods for precision medicine have been proposed, including metabolome, transcriptome, proteome, microbiome analysis etc., which reflect internal factors of organisms. Moreover, to take into account environmental influence on organisms including day/night activity, feeding and physical training regime, it was proposed to apply the descriptions of circadian system rhythmicity of each patient. Also, with organism aging, the sensitivity to external factors is raised that emphasizes the importance of the chronobiological approach in anti-aging concept. In this review we discussed available ways of the application of circadian system parameters to analyze human metabolic state. Methods. Search strategy: PubMed, Scopus, DOAJ (Directory of Open Access Journals) and Google Scholar were used to search for original research and articles review; no abstracts from meeting reports have been cited. ClinicalTrials.gov was used to search for clinical studies. Search terms included “chronotherapy”, “circadian system”, and “chronobiology”. Results. According to personalized medicine, the analysis of circadian system in the case of each patient is necessary as circadian rhythmicity varies in every person. Taking into account the peculiarities of patient’s circadian system it will be easy to choose the best time for drug administration resulting in high efficacy and low side effects. The analysis of circadian system can be performed on molecular, physiological and systemic (general, metabolic and inflammation markers) levels. There was shown the increase in the number of clinical trials which are based on the use of chronobiological approach during the treatment of different pathologies that increase with aging: depression, insomnia, metabolic and cardiovascular disease, cancer. More than 1,000 clinical trials involving circadian interventions and chronobiology have been registered worldwide. Conclusion. Chronobiological approach can be used as an additional measure to anti-aging therapy to diagnose metabolic state, to choose more effective treatment time as well as in preventive healthcare in terms of personalized medicine.

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Ercolani, Luisa, Alessio Ferrari, Claudia De Mei, Chiara Parodi, Mark Wade, and Benedetto Grimaldi. "Circadian clock: Time for novel anticancer strategies?" Pharmacological Research 100 (October 2015): 288–95. http://dx.doi.org/10.1016/j.phrs.2015.08.008.

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Nakashima, Hideaki. "Circadian rhythms in plants: Strategies for analysis." Journal of Plant Research 106, no. 4 (December 1993): 283–88. http://dx.doi.org/10.1007/bf02345971.

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Van Cauter, Eve, and Fred W. Turek. "Strategies for Resetting the Human Circadian Clock." New England Journal of Medicine 322, no. 18 (May 3, 1990): 1306–8. http://dx.doi.org/10.1056/nejm199005033221809.

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Morris, Megan B., Jennifer P. Howland, Kelly M. Amaddio, and Glenn Gunzelmann. "Aircrew Fatigue Perceptions, Fatigue Mitigation Strategies, and Circadian Typology." Aerospace Medicine and Human Performance 91, no. 4 (April 1, 2020): 363–68. http://dx.doi.org/10.3357/amhp.5396.2020.

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BACKGROUND: Human fatigue is an important factor within aviation, leading organizations to develop strategies to assess and mitigate associated risks. The U.S. Air Force’s Air Mobility Command (AMC) conducted the current pilot study to assess fatigue-related risks and issues in mobility operations. Specifically, we examined the relationship among fatigue perceptions, fatigue mitigation strategies, performance effectiveness graph reference, and circadian typology.METHODS: There were 21 volunteers from the Joint Base Charleston C-17 pilot community (Mage = 28.67; SDage = 2.11; Proportionmale = 85.71%) who completed a survey. Items referred to fatigue perceptions, fatigue mitigation strategies, performance effectiveness graph reference, and circadian typology. We examined descriptive statistics, correlations among the variables of interest, and possible moderation effects of circadian typology.RESULTS: Overall, aircrew perceived fatigue to be a serious safety of flight concern. Personal fatigue concerns and perceptions of pressure to continue missions despite fatigue were associated with increased use of the strategy of limiting light exposure during sleep episodes (r = 0.49 and 0.47). Fatigue perceptions were not directly associated with performance effectiveness graph usage. Results suggested that morning type participants might be more likely to utilize specific fatigue mitigation strategies when there are concerns of fatigue compared to evening types.DISCUSSION: Despite organizational efforts, fatigue continues to be a serious concern for the mobility community. This pilot study suggests that circadian typology might affect the relationship between fatigue perceptions and fatigue mitigation strategies and resource use. Future research should further examine these relationships and their impact within fatigue risk management (FRM) programs.Morris MB, Howland JP, Amaddio KM, Gunzelmann G. Aircrew fatigue perceptions, fatigue mitigation strategies, and circadian typology. Aerosp Med Hum Perform. 2020; 91(4):363–368.

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Kelly, Rachael M., Ultan Healy, Seamus Sreenan, John H. McDermott, and Andrew N. Coogan. "Clocks in the clinic: circadian rhythms in health and disease." Postgraduate Medical Journal 94, no. 1117 (November 2018): 653–58. http://dx.doi.org/10.1136/postgradmedj-2018-135719.

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Circadian rhythms are endogenously generated recurring patterns of around 24 hours with well-established roles in physiology and behaviour. These circadian clocks are important in both the aetiology and treatment of various psychiatric and metabolic diseases. To maintain physiological homeostasis and optimal functioning, living life synchronised to these clocks is desirable; modern society, however, promotes a ‘24/7’ lifestyle where activity often occurs during the body’s ‘biological night’, resulting in mistimed sleep and circadian misalignment. This circadian desynchrony can increase the risk of disease and can also influence treatment response. Clinicians should be aware of the influence that circadian desynchrony can have on health and disease, in order to potentially develop new therapeutic strategies and to incorporate chronotherapeutics into current treatment strategies to enhance their utility.

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Juliana, Norsham, Liyana Azmi, Nadia Mohd Effendy, Nur Islami Mohd Fahmi Teng, Izuddin Fahmy Abu, Nur Nabilah Abu Bakar, Sahar Azmani, Noor Anisah Abu Yazit, Suhaini Kadiman, and Srijit Das. "Effect of Circadian Rhythm Disturbance on the Human Musculoskeletal System and the Importance of Nutritional Strategies." Nutrients 15, no. 3 (February 1, 2023): 734. http://dx.doi.org/10.3390/nu15030734.

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The circadian system in the human body responds to daily environmental changes to optimise behaviour according to the biological clock and also influences various physiological processes. The suprachiasmatic nuclei are located in the anterior hypothalamus of the brain, and they synchronise to the 24 h light/dark cycle. Human physiological functions are highly dependent on the regulation of the internal circadian clock. Skeletal muscles comprise the largest collection of peripheral clocks in the human body. Both central and peripheral clocks regulate the interaction between the musculoskeletal system and energy metabolism. The skeletal muscle circadian clock plays a vital role in lipid and glucose metabolism. The pathogenesis of osteoporosis is related to an alteration in the circadian rhythm. In the present review, we discuss the disturbance of the circadian rhythm and its resultant effect on the musculoskeletal system. We also discuss the nutritional strategies that are potentially effective in maintaining the system’s homeostasis. Active collaborations between nutritionists and physiologists in the field of chronobiological and chrononutrition will further clarify these interactions. This review may be necessary for successful interventions in reducing morbidity and mortality resulting from musculoskeletal disturbances.

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Peng, Xuemin, Rongping Fan, Lei Xie, Xiaoli Shi, Kun Dong, Shujun Zhang, Jing Tao, et al. "A Growing Link between Circadian Rhythms, Type 2 Diabetes Mellitus and Alzheimer’s Disease." International Journal of Molecular Sciences 23, no. 1 (January 3, 2022): 504. http://dx.doi.org/10.3390/ijms23010504.

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Type 2 diabetes mellitus (T2DM) patients are at a higher risk of developing Alzheimer’s disease (AD). Mounting evidence suggests the emerging important role of circadian rhythms in many diseases. Circadian rhythm disruption is considered to contribute to both T2DM and AD. Here, we review the relationship among circadian rhythm disruption, T2DM and AD, and suggest that the occurrence and progression of T2DM and AD may in part be associated with circadian disruption. Then, we summarize the promising therapeutic strategies targeting circadian dysfunction for T2DM and AD, including pharmacological treatment such as melatonin, orexin, and circadian molecules, as well as non-pharmacological treatments like light therapy, feeding behavior, and exercise.

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Meléndez-Fernández, O. Hecmarie, Jennifer A. Liu, and Randy J. Nelson. "Circadian Rhythms Disrupted by Light at Night and Mistimed Food Intake Alter Hormonal Rhythms and Metabolism." International Journal of Molecular Sciences 24, no. 4 (February 8, 2023): 3392. http://dx.doi.org/10.3390/ijms24043392.

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Availability of artificial light and light-emitting devices have altered human temporal life, allowing 24-hour healthcare, commerce and production, and expanding social life around the clock. However, physiology and behavior that evolved in the context of 24 h solar days are frequently perturbed by exposure to artificial light at night. This is particularly salient in the context of circadian rhythms, the result of endogenous biological clocks with a rhythm of ~24 h. Circadian rhythms govern the temporal features of physiology and behavior, and are set to precisely 24 h primarily by exposure to light during the solar day, though other factors, such as the timing of meals, can also affect circadian rhythms. Circadian rhythms are significantly affected by night shift work because of exposure to nocturnal light, electronic devices, and shifts in the timing of meals. Night shift workers are at increased risk for metabolic disorder, as well as several types of cancer. Others who are exposed to artificial light at night or late mealtimes also show disrupted circadian rhythms and increased metabolic and cardiac disorders. It is imperative to understand how disrupted circadian rhythms alter metabolic function to develop strategies to mitigate their negative effects. In this review, we provide an introduction to circadian rhythms, physiological regulation of homeostasis by the suprachiasmatic nucleus (SCN), and SCN-mediated hormones that display circadian rhythms, including melatonin and glucocorticoids. Next, we discuss circadian-gated physiological processes including sleep and food intake, followed by types of disrupted circadian rhythms and how modern lighting disrupts molecular clock rhythms. Lastly, we identify how disruptions to hormones and metabolism can increase susceptibility to metabolic syndrome and risk for cardiovascular diseases, and discuss various strategies to mitigate the harmful consequences associated with disrupted circadian rhythms on human health.

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Bartman, Colleen Marie, and Tobias Eckle. "Circadian-Hypoxia Link and its Potential for Treatment of Cardiovascular Disease." Current Pharmaceutical Design 25, no. 10 (August 5, 2019): 1075–90. http://dx.doi.org/10.2174/1381612825666190516081612.

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Throughout the evolutionary time, all organisms and species on Earth evolved with an adaptation to consistent oscillations of sunlight and darkness, now recognized as ‘circadian rhythm.’ Single-cellular to multisystem organisms use circadian biology to synchronize to the external environment and provide predictive adaptation to changes in cellular homeostasis. Dysregulation of circadian biology has been implicated in numerous prevalent human diseases, and subsequently targeting the circadian machinery may provide innovative preventative or treatment strategies. Discovery of ‘peripheral circadian clocks’ unleashed widespread investigations into the potential roles of clock biology in cellular, tissue, and organ function in healthy and diseased states. Particularly, oxygen-sensing pathways (e.g. hypoxia inducible factor, HIF1), are critical for adaptation to changes in oxygen availability in diseases such as myocardial ischemia. Recent investigations have identified a connection between the circadian rhythm protein Period 2 (PER2) and HIF1A that may elucidate an evolutionarily conserved cellular network that can be targeted to manipulate metabolic function in stressed conditions like hypoxia or ischemia. Understanding the link between circadian and hypoxia pathways may provide insights and subsequent innovative therapeutic strategies for patients with myocardial ischemia. This review addresses our current understanding of the connection between light-sensing pathways (PER2), and oxygen-sensing pathways (HIF1A), in the context of myocardial ischemia and lays the groundwork for future studies to take advantage of these two evolutionarily conserved pathways in the treatment of myocardial ischemia.

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Kuehn, Bridget M. "The Heart’s Circadian Rhythms Point to Potential Treatment Strategies." Circulation 134, no. 23 (December 6, 2016): 1907–8. http://dx.doi.org/10.1161/circulationaha.116.026039.

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Man, Andy W. C., Huige Li, and Ning Xia. "Circadian Rhythm: Potential Therapeutic Target for Atherosclerosis and Thrombosis." International Journal of Molecular Sciences 22, no. 2 (January 12, 2021): 676. http://dx.doi.org/10.3390/ijms22020676.

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Every organism has an intrinsic biological rhythm that orchestrates biological processes in adjusting to daily environmental changes. Circadian rhythms are maintained by networks of molecular clocks throughout the core and peripheral tissues, including immune cells, blood vessels, and perivascular adipose tissues. Recent findings have suggested strong correlations between the circadian clock and cardiovascular diseases. Desynchronization between the circadian rhythm and body metabolism contributes to the development of cardiovascular diseases including arteriosclerosis and thrombosis. Circadian rhythms are involved in controlling inflammatory processes and metabolisms, which can influence the pathology of arteriosclerosis and thrombosis. Circadian clock genes are critical in maintaining the robust relationship between diurnal variation and the cardiovascular system. The circadian machinery in the vascular system may be a novel therapeutic target for the prevention and treatment of cardiovascular diseases. The research on circadian rhythms in cardiovascular diseases is still progressing. In this review, we briefly summarize recent studies on circadian rhythms and cardiovascular homeostasis, focusing on the circadian control of inflammatory processes and metabolisms. Based on the recent findings, we discuss the potential target molecules for future therapeutic strategies against cardiovascular diseases by targeting the circadian clock.

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Froy, Oren. "Circadian Rhythms and Obesity in Mammals." ISRN Obesity 2012 (December 9, 2012): 1–12. http://dx.doi.org/10.5402/2012/437198.

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Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating the circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabolism. Moreover, disruption of circadian rhythms leads to obesity and metabolic disorders. Therefore, it is plausible that resetting of the circadian clock can be used as a new approach to attenuate obesity. Feeding regimens, such as restricted feeding (RF), calorie restriction (CR), and intermittent fasting (IF), provide a time cue and reset the circadian clock and lead to better health. In contrast, high-fat (HF) diet leads to disrupted circadian expression of metabolic factors and obesity. This paper focuses on circadian rhythms and their link to obesity.

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Salgado-Delgado, Roberto, Araceli Tapia Osorio, Nadia Saderi, and Carolina Escobar. "Disruption of Circadian Rhythms: A Crucial Factor in the Etiology of Depression." Depression Research and Treatment 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/839743.

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Circadian factors might play a crucial role in the etiology of depression. It has been demonstrated that the disruption of circadian rhythms by lighting conditions and lifestyle predisposes individuals to a wide range of mood disorders, including impulsivity, mania and depression. Also, associated with depression, there is the impairment of circadian rhythmicity of behavioral, endocrine, and metabolic functions. Inspite of this close relationship between both processes, the complex relationship between the biological clock and the incidence of depressive symptoms is far from being understood. The efficiency and the timing of treatments based on chronotherapy (e.g., light treatment, sleep deprivation, and scheduled medication) indicate that the circadian system is an essential target in the therapy of depression. The aim of the present review is to analyze the biological and clinical data that link depression with the disruption of circadian rhythms, emphasizing the contribution of circadian desynchrony. Therefore, we examine the conditions that may lead to circadian disruption of physiology and behavior as described in depressive states, and, according to this approach, we discuss therapeutic strategies aimed at treating the circadian system and depression.

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Roenneberg, Till, and Martha Merrow. "Circadian systems: different levels of complexity." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 356, no. 1415 (November 29, 2001): 1687–96. http://dx.doi.org/10.1098/rstb.2001.0969.

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After approximately 50 years of circadian research, especially in selected circadian model systems ( Drosophila, Neurospora, Gonyaulax and, more recently, cyanobacteria and mammals), we appreciate the enormous complexity of the circadian programme in organisms and cells, as well as in physiological and molecular circuits. Many of our insights into this complexity stem from experimental reductionism that goes as far as testing the interaction of molecular clock components in heterologous systems or in vitro . The results of this enormous endeavour show circadian systems that involve several oscillators, multiple input pathways and feedback loops that contribute to specific circadian qualities but not necessarily to the generation of circadian rhythmicity. For a full appreciation of the circadian programme, the results from different levels of the system eventually have to be put into the context of the organism as a whole and its specific temporal environment. This review summarizes some of the complexities found at the level of organisms, cells and molecules, and highlights similar strategies that apparently solve similar problems at the different levels of the circadian system.

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Davis, James O. "Strategies for Managing Athletes’ Jet Lag." Sport Psychologist 2, no. 2 (June 1988): 154–60. http://dx.doi.org/10.1123/tsp.2.2.154.

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Jetting across several time zones can attenuate the performance of athletes as well as markedly reduce comfort. Circadian disorganization occurs because, while some adaptation is controlled by external factors such as light and social activity, other adaptations must wait for internal clocks to slowly synchronize. To advise athletes how best to adapt to jeg lag, the sport psychologist must consider many variables such as distance traveled and direction of flight, and choose among options such as education of the athlete and strategies for improving reentrainment.

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Gardiner, Laura-Jayne, Rachel Rusholme-Pilcher, Josh Colmer, Hannah Rees, Juan Manuel Crescente, Anna Paola Carrieri, Susan Duncan, Edward O. Pyzer-Knapp, Ritesh Krishna, and Anthony Hall. "Interpreting machine learning models to investigate circadian regulation and facilitate exploration of clock function." Proceedings of the National Academy of Sciences 118, no. 32 (August 5, 2021): e2103070118. http://dx.doi.org/10.1073/pnas.2103070118.

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The circadian clock is an important adaptation to life on Earth. Here, we use machine learning to predict complex, temporal, and circadian gene expression patterns in Arabidopsis. Most significantly, we classify circadian genes using DNA sequence features generated de novo from public, genomic resources, facilitating downstream application of our methods with no experimental work or prior knowledge needed. We use local model explanation that is transcript specific to rank DNA sequence features, providing a detailed profile of the potential circadian regulatory mechanisms for each transcript. Furthermore, we can discriminate the temporal phase of transcript expression using the local, explanation-derived, and ranked DNA sequence features, revealing hidden subclasses within the circadian class. Model interpretation/explanation provides the backbone of our methodological advances, giving insight into biological processes and experimental design. Next, we use model interpretation to optimize sampling strategies when we predict circadian transcripts using reduced numbers of transcriptomic timepoints. Finally, we predict the circadian time from a single, transcriptomic timepoint, deriving marker transcripts that are most impactful for accurate prediction; this could facilitate the identification of altered clock function from existing datasets.

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Sassone-Corsi, Paolo. "Commentary: The Year in Circadian Rhythms." Molecular Endocrinology 24, no. 11 (November 1, 2010): 2081–87. http://dx.doi.org/10.1210/me.2010-0359.

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Abstract The circadian clock orchestrates intrinsic timing in most organisms and controls a large variety of physiological and metabolic programs. In my presentation “The Year in Circadian Rhythms” at the Endocrine Society meeting (San Diego, June 2010) I reviewed some of the recent spectacular developments of the field. The exceptional interest that circadian rhythms have suscitated during the past two decades has caused a remarkable increase in the number of researchers and of committed resources dedicated to the field. This has also generated the promise of potentially novel pharmacological strategies. Indeed, specific molecular pathways of circadian regulation have been recently linked to endocrine and metabolic control, as well as cell cycle and proliferation. Importantly, circadian gene expression involves an important proportion of cellular genes, underscoring the role played by dynamic mechanisms of chromatin remodeling. This suggests that the circadian machinery could have evolved as a privileged molecular interface between cellular metabolism and epigenetic control.

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Hajak, G. "C.05.04 New strategies to resynchronise circadian rhythms in depression." European Neuropsychopharmacology 19 (September 2009): S709. http://dx.doi.org/10.1016/s0924-977x(09)71152-6.

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Santy, Patricia A., Dean M. Faulk, and Jeffrey R. Davis. "Strategies for the Preflight Circadian Shifting of Space Shuttle Crews." Journal of Clinical Pharmacology 34, no. 5 (May 1994): 535–42. http://dx.doi.org/10.1002/j.1552-4604.1994.tb04997.x.

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O’Connell, Emma J., Chloe-Anne Martinez, Yichuan G. Liang, Peter A. Cistulli, and Kristina M. Cook. "Out of breath, out of time: interactions between HIF and circadian rhythms." American Journal of Physiology-Cell Physiology 319, no. 3 (September 1, 2020): C533—C540. http://dx.doi.org/10.1152/ajpcell.00305.2020.

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Humans have internal circadian clocks that ensure that important physiological functions occur at specific times of the day. These molecular clocks are regulated at the genomic level and exist in most cells of the body. Multiple circadian resetting cues have been identified, including light, temperature, and food. Recently, oxygen has been identified as a resetting cue, and emerging science indicates that this occurs through interactions at the cellular level between the circadian transcription-translation feedback loop and the hypoxia-inducible pathway (hypoxia-inducible factor; subject of the 2019 Nobel Prize in Physiology or Medicine). This review will cover recently identified relationships between HIF and proteins of the circadian clock. Interactions between the circadian clock and hypoxia could have wide-reaching implications for human diseases, and understanding the molecular mechanisms regulating these overlapping pathways may open up new strategies for drug discovery.

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Javeed, Naureen, and Aleksey V. Matveyenko. "Circadian Etiology of Type 2 Diabetes Mellitus." Physiology 33, no. 2 (March 1, 2018): 138–50. http://dx.doi.org/10.1152/physiol.00003.2018.

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The epidemic of Type 2 diabetes mellitus necessitates development of novel therapeutic and preventative strategies to attenuate expansion of this debilitating disease. Evidence links the circadian system to various aspects of diabetes pathophysiology and treatment. The aim of this review will be to outline the rationale for therapeutic targeting of the circadian system in the treatment and prevention of Type 2 diabetes mellitus and consequent metabolic comorbidities.

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Sengupta, Shaon, Louise Ince, Francesca Sartor, Helene Borrmann, Xiaodong Zhuang, Amruta Naik, Annie Curtis, and Jane A. McKeating. "Clocks, Viruses, and Immunity: Lessons for the COVID-19 Pandemic." Journal of Biological Rhythms 36, no. 1 (January 22, 2021): 23–34. http://dx.doi.org/10.1177/0748730420987669.

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Circadian rhythms are evolutionarily conserved anticipatory systems that allow the host to prepare and respond to threats in its environment. This article summarizes a European Biological Rhythms Society (EBRS) workshop held in July 2020 to review current knowledge of the interplay between the circadian clock and viral infections to inform therapeutic strategies against SARS-CoV-2 and COVID-19. A large body of work supports the role of the circadian clock in regulating various aspects of viral replication, host responses, and associated pathogenesis. We review the evidence describing the multifaceted role of the circadian clock, spanning host susceptibility, antiviral mechanisms, and host resilience. Finally, we define the most pressing research questions and how our knowledge of chronobiology can inform key translational research priorities.

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Huang, Chen, Chenliang Zhang, Yubin Cao, Jian Li, and Feng Bi. "Major roles of the circadian clock in cancer." Cancer Biology & Medicine 20, no. 1 (January 12, 2023): 1–24. http://dx.doi.org/10.20892/j.issn.2095-3941.2022.0474.

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Circadian rhythms are natural rhythms that widely exist in all creatures, and regulate the processes and physiological functions of various biochemical reactions. The circadian clock is critical for cancer occurrence and progression. Its function is regulated by metabolic activities, and the expression and transcription of various genes. This review summarizes the composition of the circadian clock; the biological basis for its function; its relationship with, and mechanisms in, cancer; its various functions in different cancers; the effects of anti-tumor treatment; and potential therapeutic targets. Research in this area is expected to advance understanding of circadian locomotor output cycles kaput (CLOCK) and brain and muscle ARNT-like protein 1 (BMAL1) in tumor diseases, and contribute to the development of new anti-tumor treatment strategies.

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Butt, Ghazala Rauf, Zainab Abdul Qayyum, and Matthew Alan Jones. "Plant Defence Mechanisms Are Modulated by the Circadian System." Biology 9, no. 12 (December 9, 2020): 454. http://dx.doi.org/10.3390/biology9120454.

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Plant health is an important aspect of food security, with pathogens, pests, and herbivores all contributing to yield losses in crops. Plants’ defence against pathogens is complex and utilises several metabolic processes, including the circadian system, to coordinate their response. In this review, we examine how plants’ circadian rhythms contribute to defence mechanisms, particularly in response to bacterial pathogen attack. Circadian rhythms contribute to many aspects of the plant–pathogen interaction, although significant gaps in our understanding remain to be explored. We conclude that if these relationships are explored further, better disease management strategies could be revealed.

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Li, Min, Peiyu Wu, Jianhua Ding, Qi Yao, and Jiaqi Ju. "The Circadian Effect Versus Mesopic Vision Effect in Road Lighting Applications." Applied Sciences 10, no. 19 (October 6, 2020): 6975. http://dx.doi.org/10.3390/app10196975.

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Several models on the circadian effect have been applied to indoor circadian lighting design, but applications in road lighting have not yet been clarified. Based on existing models and circadian research, we examined equivalent melanopic lux (EML), circadian light (CLA), and circadian stimulus (CS) representing the circadian effect and the S/P ratio representing the mesopic vision effect, among a dataset of light sources at photopic adaptation illuminance values of 1, 3, 10, 30, and 100 lx. The results show that the S/P ratio correlates with EML and CS (or CLA) much stronger than it correlates with color temperature. The EMLs of light sources are below 50 EML in mesopic vision, and the CSs of most light sources are below or around the threshold value of 0.05. We conclude that the circadian effect is not a significant issue in mesopic vision under most conditions and that optimization for mesopic efficiency is still a good strategy. There are quite a few light sources that may achieve both ideal mesopic efficiency and low CS. This work clarifies the circadian effect and mesopic vision effect performance of light sources in mesopic vision and will help guide choosing suitable light sources and optimization strategies for road lighting.

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Campos, Luciana A., Jose Cipolla-Neto, Fernanda G. Amaral, Lisete C. Michelini, Michael Bader, and Ovidiu C. Baltatu. "The Angiotensin-Melatonin Axis." International Journal of Hypertension 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/521783.

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Accumulating evidence indicates that various biological and neuroendocrine circadian rhythms may be disrupted in cardiovascular and metabolic disorders. These circadian alterations may contribute to the progression of disease. Our studies direct to an important role of angiotensin II and melatonin in the modulation of circadian rhythms. The brain renin-angiotensin system (RAS) may modulate melatonin synthesis, a hormone with well-established roles in regulating circadian rhythms. Angiotensin production in the central nervous system may not only influence hypertension but also appears to affect the circadian rhythm of blood pressure. Drugs acting on RAS have been proven effective in the treatment of cardiovascular and metabolic disorders including hypertension and diabetes mellitus (DM). On the other hand, since melatonin is capable of ameliorating metabolic abnormalities in DM and insulin resistance, the beneficial effects of RAS blockade could be improved through combined RAS blocker and melatonin therapy. Contemporary research is evidencing the existence of specific clock genes forming central and peripheral clocks governing circadian rhythms. Further research on the interaction between these two neurohormones and the clock genes governing circadian clocks may progress our understanding on the pathophysiology of disease with possible impact on chronotherapeutic strategies.

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Humphries, Jean D. "Workplace Debt: Sleep Loss." Creative Nursing 15, no. 1 (February 2009): 23–27. http://dx.doi.org/10.1891/1078-4535.15.1.23.

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Normal sleep is characterized by definite cycles of varying sleep depths as well as synchrony with the 24-hour circadian rhythm. Irregular work schedules put nurses at risk for sleep disruption, which is associated with adverse health effects as well as decreased patient safety. Strategies based on maintaining normal sleep cycles and the circadian rhythm can help nurses avoid the adverse effects of sleep loss.

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von Allmen, Douglas C., Lauren J. Francey, Garrett M. Rogers, Marc D. Ruben, Aliza P. Cohen, Gang Wu, Robert E. Schmidt, et al. "Circadian Dysregulation: The Next Frontier in Obstructive Sleep Apnea Research." Otolaryngology–Head and Neck Surgery 159, no. 6 (September 11, 2018): 948–55. http://dx.doi.org/10.1177/0194599818797311.

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Objective To review the effects of the circadian clock on homeostasis, the functional interaction between the circadian clock and hypoxia-inducible factors, and the role of circadian dysregulation in the progression of cardiopulmonary disease in obstructive sleep apnea (OSA). Data Sources The MEDLINE database was accessed through PubMed. Review Methods A general review is presented on molecular pathways disrupted in OSA, circadian rhythms and the role of the circadian clock, hypoxia signaling, crosstalk between the circadian and hypoxia systems, the role of the circadian clock in cardiovascular disease, and implications for practice. Studies included in this State of the Art Review demonstrate the potential contribution of the circadian clock and hypoxia in animal models or human disease. Conclusions Molecular crosstalk between the circadian clock and hypoxia-inducible factors has not been evaluated in disease models of OSA. Implications for Practice Pediatric OSA is highly prevalent and, if left untreated, may lead to cardiopulmonary sequelae. Changes in inflammatory markers that normally demonstrate circadian rhythmicity are also seen among patients with OSA. Hypoxia-inducible transcription factors interact with core circadian clock transcription factors; however, the interplay between these pathways has not been elucidated in the cardiopulmonary system. This gap in knowledge hinders our ability to identify potential biomarkers of OSA and develop alternative therapeutic strategies. A deeper understanding of the mechanisms by which OSA impinges on clock function and the impact of clock dysregulation on the cardiopulmonary system may lead to future advancements for the care of patients with OSA. The aim of this review is to shed light on this important clinical topic.

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Satyanarayanan, Senthil Kumaran, Huanxing Su, Yi-Wen Lin, and Kuan-Pin Su. "Circadian Rhythm and Melatonin in the Treatment of Depression." Current Pharmaceutical Design 24, no. 22 (October 19, 2018): 2549–55. http://dx.doi.org/10.2174/1381612824666180803112304.

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Background: Circadian rhythm disruption underlies the pathophysiology of psychiatric disorders, especially depression. Both pharmacological and non-pharmacological strategies affecting endogenous circadian rhythms have been developed with specificity to alter the circadian dysfunction. The current management strategy with antidepressants is far from being satisfactory in addressing this issue. In recent years, attempts at discovering new antidepressants focused on a melatonergic system which is known to be altered in depression have led to a potential option for treatment of depression. Methods: We reviewed all recently published relevant articles on melatonin and its analogues to look for their implication in the treatment of circadian rhythm disruption and depression. Results: Melatonin, a pleiotropic regulator molecule and its analogues (ramelteon, agomelatine, TIK-301, Neu- P11 and tasimelteon) have been observed to resynchronize the circadian rhythm and some were said to alleviate depressive symptoms in depressed subjects. Conclusion: This review focuses on substantial advances in the melatonin-based chronobiologic intervention and its responses in the treatment of depression.

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Sun, Qiaoyu, Chi-Tang Ho, Xin Zhang, Yanan Liu, Ruilin Zhang, and Zufang Wu. "Strategies for circadian rhythm disturbances and related psychiatric disorders: a new cue based on plant polysaccharides and intestinal microbiota." Food & Function 13, no. 3 (2022): 1048–61. http://dx.doi.org/10.1039/d1fo02716f.

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Hu, Yuedi, Tiantian He, Jie Zhu, Xiaole Wang, Jiabing Tong, Zegeng Li, and Jingcheng Dong. "The Link between Circadian Clock Genes and Autophagy in Chronic Obstructive Pulmonary Disease." Mediators of Inflammation 2021 (October 25, 2021): 1–7. http://dx.doi.org/10.1155/2021/2689600.

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Chronic obstructive pulmonary disease (COPD), a progressive respiratory disease, is characterized by the alveolar epithelium injury and persistent airway inflammation. It is documented that oscillation and dysregulated expression of circadian clock genes, like Bmal1, Per1, and Per2, involved in COPD pathogenies, including chronic inflammation and imbalanced autophagy level, and targeting the associations of circadian rhythm and autophagy is promising strategies in the management and treatment of COPD. Herein, we reviewed the mechanisms of the circadian clock and the unbalance of the autophagic level in COPD, as well as the link between the two, so as to provide further theoretical bases for the study on the pathogenesis of COPD.

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Chawla, Shreya, Spyridon Beretoulis, Aaron Deere, and Dina Radenkovic. "The Window Matters: A Systematic Review of Time Restricted Eating Strategies in Relation to Cortisol and Melatonin Secretion." Nutrients 13, no. 8 (July 23, 2021): 2525. http://dx.doi.org/10.3390/nu13082525.

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Time-Restricted Eating is an eating pattern based on the circadian rhythm which limits daily food intake (usually to ≤12 h/day), unique in that no overt restriction is imposed on the quality, nor quantity, of food intake. This paper aimed to examine the effects of two patterns of TRE, traditional TRE, and Ramadan fasting, on two markers of circadian rhythm, cortisol and melatonin. PubMed and Web of Science were searched up to December 2020 for studies examining the effects of time restricted eating on cortisol and melatonin. Fourteen studies met our inclusion criteria. All Ramadan papers found statistically significant decrease in melatonin (p < 0.05) during Ramadan. Two out of the three Ramadan papers noted an abolishing of the circadian rhythm of cortisol (p < 0.05). The non-Ramadan TRE papers did not examine melatonin, and cortisol changes were mixed. In studies comparing TRE to control diets, Stratton et al. found increased cortisol levels in the non-TRE fasting group (p = 0.0018) and McAllister et al. noted no difference. Dinner-skipping resulted in significantly reduced evening cortisol and non-significantly raised morning cortisol. Conversely, breakfast skipping resulted in significantly reduced morning cortisol. This blunting indicates a dysfunctional HPA axis, and may be associated with poor cardio-metabolic outcomes. There is a paucity of research examining the effects of TRE on cortisol and melatonin. The contrasting effect of dinner and breakfast-skipping should be further examined to ascertain whether timing the feeding window indeed has an impact on circadian rhythmicity.

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Maury, Eleonore. "Off the Clock: From Circadian Disruption to Metabolic Disease." International Journal of Molecular Sciences 20, no. 7 (March 30, 2019): 1597. http://dx.doi.org/10.3390/ijms20071597.

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Circadian timekeeping allows appropriate temporal regulation of an organism’s internal metabolism to anticipate and respond to recurrent daily changes in the environment. Evidence from animal genetic models and from humans under circadian misalignment (such as shift work or jet lag) shows that disruption of circadian rhythms contributes to the development of obesity and metabolic disease. Inappropriate timing of food intake and high-fat feeding also lead to disruptions of the temporal coordination of metabolism and physiology and subsequently promote its pathogenesis. This review illustrates the impact of genetically or environmentally induced molecular clock disruption (at the level of the brain and peripheral tissues) and the interplay between the circadian system and metabolic processes. Here, we discuss some mechanisms responsible for diet-induced circadian desynchrony and consider the impact of nutritional cues in inter-organ communication, with a particular focus on the communication between peripheral organs and brain. Finally, we discuss the relay of environmental information by signal-dependent transcription factors to adjust the timing of gene oscillations. Collectively, a better knowledge of the mechanisms by which the circadian clock function can be compromised will lead to novel preventive and therapeutic strategies for obesity and other metabolic disorders arising from circadian desynchrony.

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Meiliana, Anna, Nurrani Mustika Dewi, and Andi Wijaya. "Chronodisruption and Obesity." Indonesian Biomedical Journal 7, no. 3 (December 1, 2015): 117. http://dx.doi.org/10.18585/inabj.v7i3.184.

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BACKGROUND: Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabolism. Moreover, disruption of circadian rhythms leads to obesity and metabolic disorders.CONTENT:Regularly alternating periods of light and darkness, such as normally occur with the rising and the setting of the sun, are essential for the maintenance of undisturbed circadian rhythms in all organisms including humans. The light-dark environment, as detected by specialized photoreceptors in the retinas, impacts the endogenous circadian clock in the anterior hypothalamus, the suprachiasmatic nuclei. These nuclei, via both neural and humoral signals, communicate with cells throughout the organism to establish regular circadian rhythms. The introduction of artificial sources of light roughly 150 years ago has significantly undermined the naturally occurring light-dark environment and, likewise, has disturbed circadian rhythms since light is now available at unusual times, i.e., at night. Light at night is known to cause circadian disruption and melatonin suppression. Many potentially pathophysiological consequences of these artificial light-mediated changes, include cancer, cardiovascular diseases, insomnia, metabolic syndrome, diabetes, and cognitive disorders may be aggravated by the increased exposure to light at night, which is inevitable in well-developed societies that have undergone extensive electrification.SUMMARY: Therefore, it is plausible that resetting of the circadian clock can be used as a new approach to attenuate obesity. Feeding regimens, such as restricted feeding, calorie restriction and intermittent fasting, provide a time cue and reset the circadian clock and lead to better health. In contrast, high-fat diet leads to disrupted circadian expression of metabolic factors and obesity.KEYWORDS: obesity, circadian clock, metabolism, chronodisruption

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Walker, William H., Jacob R. Bumgarner, James C. Walton, Jennifer A. Liu, O. Hecmarie Meléndez-Fernández, Randy J. Nelson, and A. Courtney DeVries. "Light Pollution and Cancer." International Journal of Molecular Sciences 21, no. 24 (December 8, 2020): 9360. http://dx.doi.org/10.3390/ijms21249360.

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For many individuals in industrialized nations, the widespread adoption of electric lighting has dramatically affected the circadian organization of physiology and behavior. Although initially assumed to be innocuous, exposure to artificial light at night (ALAN) is associated with several disorders, including increased incidence of cancer, metabolic disorders, and mood disorders. Within this review, we present a brief overview of the molecular circadian clock system and the importance of maintaining fidelity to bright days and dark nights. We describe the interrelation between core clock genes and the cell cycle, as well as the contribution of clock genes to oncogenesis. Next, we review the clinical implications of disrupted circadian rhythms on cancer, followed by a section on the foundational science literature on the effects of light at night and cancer. Finally, we provide some strategies for mitigation of disrupted circadian rhythms to improve health.

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van Wamelen, Daniel J., Raymund AC Roos, and Nasir A. Aziz. "Therapeutic strategies for circadian rhythm and sleep disturbances in Huntington disease." Neurodegenerative Disease Management 5, no. 6 (December 2015): 549–59. http://dx.doi.org/10.2217/nmt.15.45.

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van Reeth, Olivier. "Sleep and Circadian Disturbances in Shift Work: Strategies for Their Management." Hormone Research in Paediatrics 49, no. 3-4 (1998): 158–62. http://dx.doi.org/10.1159/000023164.

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Tucci, Valter. "Sleep, Circadian Rhythms and Interval Timing: Evolutionary Strategies to Time Information." Procedia - Social and Behavioral Sciences 126 (March 2014): 11–14. http://dx.doi.org/10.1016/j.sbspro.2014.02.300.

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Maple, Amanda M., Rachel K. Rowe, Jonathan Lifshitz, Fabian Fernandez, and Amelia L. Gallitano. "Influence of Schizophrenia-Associated Gene Egr3 on Sleep Behavior and Circadian Rhythms in Mice." Journal of Biological Rhythms 33, no. 6 (October 15, 2018): 662–70. http://dx.doi.org/10.1177/0748730418803802.

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Up to 80% of people meeting DSM-IV definitions for schizophrenia will exhibit difficulties with sleep, along with a breakdown in circadian entrainment and rhythmicity. The changes to the sleep and circadian systems in this population are thought to be interdependent, as evidenced by the frequent use of the combined term “sleep and circadian rhythm disruption” or “SCRD” to describe their occurrence. To understand links between sleep and circadian problems in the schizophrenia population, we analyzed the duration and rhythmicity of sleep behavior in mice lacking function of the immediate early gene early growth response 3 ( Egr3). EGR3 has been associated with schizophrenia risk in humans, and Egr3-deficient (-/-) mice display various features of schizophrenia that are responsive to antipsychotic treatment. While Egr3-/- mice slept less than their wildtype (WT) littermates, they showed no evidence of circadian disorganization; in fact, circadian rhythms of activity were more robust in these mice compared with WT, as measured by time series analysis and the relative amplitude index of Van Someren’s suite of non-parametric circadian rhythm analyses. Differences in circadian robustness were maintained when the animals were transferred to several weeks of housing under constant darkness or constant light. Together, our results suggest that Egr3-/- mice retain control over the circadian timekeeping of sleep and wake, while showing impaired sleep. The findings are compatible with those from a surprising array of mouse models of schizophrenia and raise the possibility that SCRD may be 2 separate disorders in the schizophrenia population requiring different treatment strategies.

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Salamatova DO, Yulia, and Andreja Packard MD. "Effects of Circadian Rhythm on Migraine Therapy." OBM Neurobiology 5, no. 4 (June 24, 2021): 1. http://dx.doi.org/10.21926/obm.neurobiol.2104111.

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Circadian rhythms are 24-hour cycles of physical, mental, and behavioral changes regulated and maintained by the internal primary circadian clock, however modifiable by a number of external cues or “zeitgebers”, the most powerful one being light. Core set of clock genes regulate the whole-body metabolism and transcription of over 40% of mammalian RNA, including that for drug transporters, binding and metabolizing proteins responsible for regulation of pharmacokinetics of vast array of medications. Growing amount of evidence also shows circadian rhythmicity of a number of patho-physiological processes, such as are migraine, chronic pain, and epilepsy, suggesting amenability to chronotherapy. Chronotherapy involves behavioral and pharmacological strategies to restore or correct ill-functioning circadian rhythm as well as manipulation of standardized treatments throughout the day to maximize therapeutic and minimize side effects, termed chronopharmacology. Chronotherapy for chronic migraines and headache variants using synchronization techniques as well as chronopharmacology of abortive and preventive migraine medications is being actively researched. In this review, we summarize current state of chronotherapy for headache variants and discuss future prospects in circadian optimization of migraine headaches treatment.

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Nakao, Atsuhito. "Temporal Regulation of Cytokines by the Circadian Clock." Journal of Immunology Research 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/614529.

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Several parameters of the immune system exhibit oscillations with a period of approximately 24 hours that refers to “circadian rhythms.” Such daily variations in host immune system status might evolve to maximize immune reactions at times when encounters with pathogens are most likely to occur. However, the mechanisms behind circadian immunity have not been fully understood. Recent studies reveal that the internal time keeping system “circadian clock” plays a key role in driving the daily rhythms evident in the immune system. Importantly, several studies unveil molecular mechanisms of how certain clock proteins (e.g., BMAL1 and CLOCK) temporally regulate expression of cytokines. Since cytokines are crucial mediators for shaping immune responses, this review mainly summarizes the new knowledge that highlights an emerging role of the circadian clock as a novel regulator of cytokines. A greater understanding of circadian regulation of cytokines will be important to exploit new strategies to protect host against infection by efficient cytokine induction or to treat autoimmunity and allergy by ameliorating excessive activity of cytokines.

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Buxton, Orfeu M., Mireille L'Hermite-Balériaux, Fred W. Turek, and Eve van Cauter. "Daytime naps in darkness phase shift the human circadian rhythms of melatonin and thyrotropin secretion." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 278, no. 2 (February 1, 2000): R373—R382. http://dx.doi.org/10.1152/ajpregu.2000.278.2.r373.

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To systematically determine the effects of daytime exposure to sleep in darkness on human circadian phase, four groups of subjects participated in 4-day studies involving either no nap (control), a morning nap (0900–1500), an afternoon nap (1400–2000), or an evening nap (1900–0100) in darkness. Except during the scheduled sleep/dark periods, subjects remained awake under constant conditions, i.e., constant dim light exposure (36 lx), recumbence, and caloric intake. Blood samples were collected at 20-min intervals for 64 h to determine the onsets of nocturnal melatonin and thyrotropin secretion as markers of circadian phase before and after stimulus exposure. Sleep was polygraphically recorded. Exposure to sleep and darkness in the morning resulted in phase delays, whereas exposure in the evening resulted in phase advances relative to controls. Afternoon naps did not change circadian phase. These findings indicate that human circadian phase is dependent on the timing of darkness and/or sleep exposure and that strategies to treat circadian misalignment should consider not only the timing and intensity of light, but also the timing of darkness and/or sleep.

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Ali, Amira A. H., and Charlotte von Gall. "Adult Neurogenesis under Control of the Circadian System." Cells 11, no. 5 (February 22, 2022): 764. http://dx.doi.org/10.3390/cells11050764.

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The mammalian circadian system is a hierarchically organized system, which controls a 24-h periodicity in a wide variety of body and brain functions and physiological processes. There is increasing evidence that the circadian system modulates the complex multistep process of adult neurogenesis, which is crucial for brain plasticity. This modulatory effect may be exercised via rhythmic systemic factors including neurotransmitters, hormones and neurotrophic factors as well as rhythmic behavior and physiology or via intrinsic factors within the neural progenitor cells such as the redox state and clock genes/molecular clockwork. In this review, we discuss the role of the circadian system for adult neurogenesis at both the systemic and the cellular levels. Better understanding of the role of the circadian system in modulation of adult neurogenesis can help develop new treatment strategies to improve the cognitive deterioration associated with chronodisruption due to detrimental light regimes or neurodegenerative diseases.

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Foster, Takesha R., Kwesi A. Dadzie, Olivia Adams, and Melanie R. Gubbels-Bupp. "The Effect of Malnutrition on T-cell Circadian Rhythms." Journal of Immunology 208, no. 1_Supplement (May 1, 2022): 167.07. http://dx.doi.org/10.4049/jimmunol.208.supp.167.07.

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Abstract In mammals, T-cell migration is under circadian control, likely to anticipate daily rhythms in infection risk. Glucocorticoids are a major controller of circadian processes and malnutrition is associated with increased glucocorticoid secretion. Previous studies suggest malnutrition may impart a “super-quiescent” phenotype to T-cells, enabling a greater number of naïve T-cells to survive short-term malnutrition albeit with diminished function. Thus, we hypothesize that malnourished T-cells may conserve energy by disengaging from rhythmic migration under circadian control and/or foregoing migration to reside in the bone marrow instead. To test this hypothesis, the total number of nucleated cells and naïve CD4+ and CD8+ T-cells in the blood, spleen, bone marrow, and brachial and mesenteric lymph nodes were enumerated by flow cytometry every four hours over the course of one day from control and malnourished mice. Additionally, expression levels of CD127 and CXCR4 in both T-cell populations and the concentration of glucocorticoids in the blood were assessed. A better understanding of how malnutrition affects the circadian rhythm of T-cell migration will not only help identify the mechanisms of how circadian rhythms work, but also how organisms’ circadian rhythms change in response to malnutrition. This knowledge of how malnutrition disrupts the circadian rhythm of T-cells may help improve vaccination strategies in malnourished children. Supported by NSF-MRI [DBI- 1920116] NSF -RUI [IOS-1951881]

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Moore-Ede, MC. "Jet Lag, Shift Work, and Maladaption." Physiology 1, no. 5 (October 1, 1986): 156–60. http://dx.doi.org/10.1152/physiologyonline.1986.1.5.156.

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The circadian pacemakers, which time the approximately 24-h cycle of sleep and wakefulness, resynchronize only slowly after an abrupt phase shift in environmental time cues. Consequently, we are not well equipped to cope with jet travel across multiple time zones or with rotating shift work schedules, neither of which was in the evolutionary experience of the human species. Recent studies of the human circadian system suggest some strategies to minimize the ill effects of jet lag and shift work.

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Agarwal, Rajiv. "Relationship between circadian blood pressure variation and circadian protein excretion in CKD." American Journal of Physiology-Renal Physiology 293, no. 3 (September 2007): F655—F659. http://dx.doi.org/10.1152/ajprenal.00188.2007.

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Circadian blood pressure changes are blunted in patients with chronic kidney disease (CKD). Proteinuria is the most important correlate of hypertension in CKD. However, little is known about the influence of circadian blood pressure changes and variation in protein excretion rate. Furthermore, the impact of blood pressure components, e.g., mean arterial pressure and pulse pressure, on proteinuria has not been evaluated. To analyze the relationship of circadian changes in blood pressure on urinary protein excretion patterns, glomerular filtration rate was measured with iothalamate clearance and 24-h ambulatory blood pressure with SpaceLabs 90207 monitor in 22 patients with CKD. It was found that hourly protein excretion rates were 31% higher during the night. Excretion results of sodium, potassium, chloride, urea, and creatinine were also between 30 and 40% higher at night. Systolic, mean arterial, and pulse pressures but not diastolic pressure were related to daytime protein excretion rate. At night, the relationship of systolic, diastolic, and mean arterial pressures was significantly lower and essentially flat with respect to protein excretion rate, but the relationship of pulse pressure and proteinuria was not different from that seen during the day. Circadian variation in blood pressure did not impact circadian sodium excretion rate. In conclusion, these data suggest that patients with CKD have patterns of proteinuria that share different relationships with blood pressure components depending on the awake-sleep state. Pulse pressure is related to proteinuria independent of the awake-sleep state. Reducing mean arterial pressure during the day and pulse pressure during the day or night may be effective antiproteinuric strategies.

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Chowdhury, Debajyoti, Chao Wang, Ai-Ping Lu, and Hai-Long Zhu. "Understanding Quantitative Circadian Regulations Are Crucial Towards Advancing Chronotherapy." Cells 8, no. 8 (August 13, 2019): 883. http://dx.doi.org/10.3390/cells8080883.

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Circadian rhythms have a deep impact on most aspects of physiology. In most organisms, especially mammals, the biological rhythms are maintained by the indigenous circadian clockwork around geophysical time (~24-h). These rhythms originate inside cells. Several core components are interconnected through transcriptional/translational feedback loops to generate molecular oscillations. They are tightly controlled over time. Also, they exert temporal controls over many fundamental physiological activities. This helps in coordinating the body’s internal time with the external environments. The mammalian circadian clockwork is composed of a hierarchy of oscillators, which play roles at molecular, cellular, and higher levels. The master oscillation has been found to be developed at the hypothalamic suprachiasmatic nucleus in the brain. It acts as the core pacemaker and drives the transmission of the oscillation signals. These signals are distributed across different peripheral tissues through humoral and neural connections. The synchronization among the master oscillator and tissue-specific oscillators offer overall temporal stability to mammals. Recent technological advancements help us to study the circadian rhythms at dynamic scale and systems level. Here, we outline the current understanding of circadian clockwork in terms of molecular mechanisms and interdisciplinary concepts. We have also focused on the importance of the integrative approach to decode several crucial intricacies. This review indicates the emergence of such a comprehensive approach. It will essentially accelerate the circadian research with more innovative strategies, such as developing evidence-based chronotherapeutics to restore de-synchronized circadian rhythms.

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Salazar, Andrew, and Jörg von Hagen. "Circadian Oscillations in Skin and Their Interconnection with the Cycle of Life." International Journal of Molecular Sciences 24, no. 6 (March 15, 2023): 5635. http://dx.doi.org/10.3390/ijms24065635.

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Periodically oscillating biological processes, such as circadian rhythms, are carefully concerted events that are only beginning to be understood in the context of tissue pathology and organismal health, as well as the molecular mechanisms underlying these interactions. Recent reports indicate that light can independently entrain peripheral circadian clocks, challenging the currently prevalent hierarchical model. Despite the recent progress that has been made, a comprehensive overview of these periodic processes in skin is lacking in the literature. In this review, molecular circadian clock machinery and the factors that govern it have been highlighted. Circadian rhythm is closely linked to immunological processes and skin homeostasis, and its desynchrony can be linked to the perturbation of the skin. The interplay between circadian rhythm and annual, seasonal oscillations, as well as the impact of these periodic events on the skin, is described. Finally, the changes that occur in the skin over a lifespan are presented. This work encourages further research into the oscillating biological processes occurring in the skin and lays the foundation for future strategies to combat the adverse effects of desynchrony, which would likely have implications in other tissues influenced by periodic oscillatory processes.

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Silva, Fernando, Manuel Vaz, and José Carlos Carneiro. "Alterações do Ritmo Circadiano no Atleta." Revista de Medicina Desportiva Informa 12, no. 6 (November 1, 2021): 18–22. http://dx.doi.org/10.23911/ritmo_circadiano_2021_nov.

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Sleep is very important for the proper functioning of the human body and consists of several stages. This text will address the concepts of biological rhythms, the circadian rhythm and body temperature, which is considered the main biological marker of the circadian rhythm. Their disorders have an influence on the athlete’s performance, with jet lag being approached. The diagnosis of these disorders can be made through various subjective and objective methods. Finally, adaptation strategies will be mentioned, addressing physical exercise, diet, and medication, among others.

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Journal articles on the topic 'Circadian strategies'

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