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Positive affect circadian

Jia-Lang Zheng, Shuang-Shuang Yuan, Chang-Wen Wu, Zhen-Ming Lv, Ai-Yi Zhu
Up to date, little information is available on effects of circadian rhythm on metal-induced toxicity in fish. In this study, zebrafish were acutely exposed to 0.97mgL(-1) cadmium for 12h either at ZT0 (the light intensity began to reached maximum) or at ZT12 (light intensity began to reached minimum) to evaluate the temporal sensitivity of oxidative stress and inflammatory responses in the brain of zebrafish. Profiles of responses of some genes at mRNA, protein and activity levels were different between ZT0 and ZT12 in the normal water...
November 18, 2016: Aquatic Toxicology
Diane J Kim, Nathan St Louis, Ralph A Molaro, Glenn T Hudson, Robert C Chorley, Brenda J Anderson
Psychological stressors elicit the anticipation of homeostatic challenge, whereas physical stressors are direct threats to homeostasis. Many rodent models of stress include both types of stressors, yet deficits, like those reported for working memory, are often attributed to psychological stress. To empirically test whether intermittent psychological stressors, such as repeated threats, are solely sufficient to impair spatial working memory, we developed a novel rodent model of stress that is restricted to the anticipation of threat, and free of direct physical challenge...
November 21, 2016: Neurobiology of Learning and Memory
Peter Cronin, Michael J McCarthy, Andrew S P Lim, David P Salmon, Douglas Galasko, Eliezer Masliah, Philip L De Jager, David A Bennett, Paula Desplats
INTRODUCTION: Circadian alterations are prevalent in Alzheimer's disease (AD) and may contribute to cognitive impairment, behavioral symptoms, and neurodegeneration. Epigenetic mechanisms regulate the circadian clock, and changes in DNA methylation have been reported in AD brains, but the pathways that mediate circadian deregulation in AD are incompletely understood. We hypothesized that aberrant DNA methylation may affect circadian rhythms in AD. METHODS: We investigated DNA methylation, transcription, and expression of BMAL1, a positive regulator of the circadian clock, in cultured fibroblasts and brain samples from two independent cohorts of aging and AD...
November 21, 2016: Alzheimer's & Dementia: the Journal of the Alzheimer's Association
Xu Li, Dingbang Ma, Sheen X Lu, Xinyi Hu, Rongfeng Huang, Tong Liang, Tongda Xu, Elaine M Tobin, Hongtao Liu
Light and temperature are two key environmental signals that profoundly affect plant growth and development, but underlying molecular mechanisms of how light and temperature signals affect the circadian clock are largely unknown. Here we report that COR27 and COR28 are regulated not only by low temperatures but also by light signals. COR27 and COR28 are negative regulators of freezing tolerance but positive regulators of flowering, possibly representing a trade-off between freezing tolerance and flowering. Furthermore, loss-of-function mutations in COR27 and COR28 result in period lengthening of various circadian output rhythms and affect central clock gene expression...
November 11, 2016: Plant Cell
Qingming Tang, Bo Cheng, Mengru Xie, Yatao Chen, Jiajia Zhao, Xin Zhou, Lili Chen
Circadian clock genes regulate cancer development and chemotherapy susceptibility. Accordingly, chronotherapy based on circadian phenotypes might be applied to improve therapeutic efficacy. In this study, we investigated whether the circadian clock gene Bmal1 inhibited tumor development and increased paclitaxel sensitivity in tongue squamous cell carcinoma (TSCC). Bmal1 expression was downregulated and its rhythmic pattern of expression was affected in TSCC samples and cell lines. Ectopic Bmal1 inhibited cell proliferation, migration and invasion in vitro and tumor growth in mouse xenograft models of TSCC...
November 7, 2016: Cancer Research
Adrian Andrzej Chrobak, Anna Tereszko, Daria Dembinska-Krajewska, Aleksandra Arciszewska, Marcin Siwek, Dominika Dudek, Janusz Rybakowski
Chronotype is a stable trait presenting one's circardian preference. Since chronotype disturbances are common in patients with affective disorders, our aim is to evaluate chronotypes related to affective temperaments, measured with the temperament evaluation of Memphis, Pisa and San Diego-Autoquestionnaire (TEMPS-A). The study included 618 subjects (151 men and 467 women) within the framework of web-based design. They all fulfilled a questionnaire, consisting of the Composite Scale of Morningness (CSM), Sleep Wake Pattern Assessment Questionnaire (SWPAQ), and the TEMPS-A scale...
October 13, 2016: Chronobiology International
Mohammad Haddadi, Samaneh Reiszadeh Jahromi, Upendra Nongthomba, T Shivanandappa, S R Ramesh
Oxidative stress is one of the major etiological factors implicated in pathogenesis of neurodegenerative diseases. Since neurons are more sensitive to oxidative damage there is an increasing interest in developing novel antioxidant therapies, especially herbal preparations due to their safety profile and high efficiency. In this regard, the neuroprotective potential of a novel antioxidant compound, 4-hydroxyisophthalic acid (4-HIPA) isolated from aqueous extract of Decalepis hamiltonii roots was examined using transgenic Drosophila model of taupathy expressing wild-type and mutant forms of 2N4R isoform of human microtubule associated protein tau (MAPT)...
September 9, 2016: Neurochemistry International
Leonardo Rodríguez-Sosa, Gabina Calderón-Rosete, Aída Ortega-Cambranis, Francisco F De-Miguel
The biogenic amine octopamine (OA) modulates invertebrate behavior by changing neuronal responses from sensory inputs to motor outputs. However, the OA modulation of visual sensitivity and its possible coupling to diurnal cycles remains unexplored. Here we studied the diurnal variations in the OA levels in the hemolymph of the crayfish Procambarus clarkii, its release from the structures in the eyestalk and its modulation of the retinal light sensitivity. The hemolymph concentration of OA and its amino acid precursor tyrosine was measured by high-resolution liquid chromatography; OA varied along the 24-hcycle...
September 1, 2016: Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology
Alicia Carissimi, Alessandra Castro Martins, Fabiane Dresch, Lilian Corrêa da Silva, Cristian Patrick Zeni, Maria Paz Hidalgo
School start time influences sleep parameters. Differences between circadian sleep parameters on weekends and weekdays have been associated with obesity, sleep, and psychiatric disorders. Moreover, circadian rhythm dysregulation affects the secretion of some hormones, such as melatonin and cortisol. In the current study, we investigate the effect of school start time on cortisol and melatonin levels in a community sample of Brazilian children and adolescents. This was a cross-sectional study of 454 students (mean age, 12...
2016: Chronobiology International
Shariq Najeeb, Zohaib Khurshid, Sana Zohaib, Muhammad Sohail Zafar
Melatonin (N-acetyl-5-methoxy tryptamine) is a substance secreted by multiple organs in vertebrates. In addition to playing a part in the circadian cycle of the body, melatonin is known to have antioxidant, antiinflammatory, and antioncotic effects on human tissues. Oral cavity is affected by a number of conditions such as periodontitis, mucositis, cancers, and cytotoxicity from various drugs or biomaterials. Research has suggested that melatonin is effective in treating the aforementioned pathologies. Furthermore, melatonin has been observed to enhance osseointegration and bone regeneration...
August 2016: Kaohsiung Journal of Medical Sciences
Feng Li, Kan Sun, Diaozhu Lin, Yiqin Qi, Yan Li, Li Yan, Meng Ren
OBJECTIVE: Menopause can affect the physiological timing system, which could result in circadian rhythm changes and development of napping habits. Whether longtime napping in postmenopausal women is associated with cardiovascular disease is, however, still debated. The present study aims to investigate this association. METHODS: We conducted a population-based study in 4,616 postmenopausal Chinese women. Information on sleep duration was self-reported. The Framingham General Cardiovascular Risk Score was calculated and used to identify participants at high risk of coronary heart disease (CHD)...
September 2016: Menopause: the Journal of the North American Menopause Society
Tuo Xue, Chunnian Song, Qing Wang, Yan Wang, Guangju Chen
The circadian locomotor output cycles kaput (CLOCK), and brain and muscle ARNT-like 1 (BMAL1) proteins are important transcriptional factors of the endogenous circadian clock. The CLOCK and BMAL1 proteins can regulate the transcription-translation activities of the clock-related genes through the DNA binding. The hetero-/homo-dimerization and DNA combination of the CLOCK and BMAL1 proteins play a key role in the positive and negative transcriptional feedback processes. In the present work, we constructed a series of binary and ternary models for the bHLH/bHLH-PAS domains of the CLOCK and BMAL1 proteins, and the DNA molecule, and carried out molecular dynamics simulations, free energy calculations and conformational analysis to explore the interaction properties of the CLOCK and BMAL1 proteins with DNA...
2016: PloS One
Angela R Ozburn, Kush Purohit, Puja K Parekh, Gabrielle N Kaplan, Edgardo Falcon, Shibani Mukherjee, Hannah M Cates, Colleen A McClung
Circadian rhythm disruptions are prominently associated with bipolar disorder (BD). Circadian rhythms are regulated by the molecular clock, a family of proteins that function together in a transcriptional-translational feedback loop. The CLOCK protein is a key transcription factor of this feedback loop, and previous studies have found that manipulations of the Clock gene are sufficient to produce manic-like behavior in mice (1). The CLOCK 3111T/C single-nucleotide polymorphism (SNP; rs1801260) is a genetic variation of the human CLOCK gene that is significantly associated with increased frequency of manic episodes in BD patients (2)...
2016: Frontiers in Psychiatry
Hiroyuki Sasaki, Yuta Hattori, Yuko Ikeda, Mayo Kamagata, Shiho Iwami, Shinnosuke Yasuda, Shigenobu Shibata
Circadian rhythms are regulated by the suprachiasmatic nucleus (SCN) clock, which is the main oscillator and peripheral clock. SCN clock can be entrained by both photic and non-photic stimuli, and an interaction exists between photic and non-photic entrainment. Moreover, peripheral circadian clocks can be entrained not only by scheduled restricted feeding, but also by scheduled exercise. Thus, the entrainment of peripheral circadian clocks may be the result of an interaction between the entrainment caused by feeding and exercise...
2016: Chronobiology International
Margriet S Westerterp-Plantenga
Circadian alignment is crucial for body-weight management, and for metabolic health. In this context, circadian alignment consists of alignment of sleep, meal patterns and physical activity. During puberty a significant reduction in sleep duration occurs, and pubertal status is inversely associated with sleep duration. A consistent inverse association between habitual sleep duration and body-weight development occurs, independent of possible confounders. Research on misalignment reveals that circadian misalignment affects sleep-architecture and subsequently disturbs glucose-insulin metabolism, substrate oxidation, leptin- and ghrelin concentrations, appetite, food reward, hypothalamic-pituitary-adrenal-axis activity and gut-peptide concentrations enhancing positive energy balance and metabolic disturbance...
April 27, 2016: Proceedings of the Nutrition Society
Mickal Houadria, Nico Blüthgen, Alex Salas-Lopez, Mona-Isabel Schmitt, Johanna Arndt, Eric Schneider, Jérôme Orivel, Florian Menzel
The diversity-stability relationship has been under intense scrutiny for the past decades, and temporal asynchrony is recognized as an important aspect of ecosystem stability. In contrast to relatively well-studied interannual and seasonal asynchrony, few studies investigate the role of circadian cycles for ecosystem stability. Here, we studied multifunctional redundancy of diurnal and nocturnal ant communities in four tropical rain forest sites. We analyzed how it was influenced by species richness, functional performance, and circadian asynchrony...
January 2016: Ecology
Magda J Castelhano-Carlos, Vera Baumans, Nuno Sousa
The use of animals is essential in biomedical research. The laboratory environment where the animals are housed has a major impact on them throughout their lives and influences the outcome of animal experiments. Therefore, there has been an increased effort in the refinement of laboratory housing conditions which is explicitly reflected in international regulations and recommendations. Since housing conditions affect behaviour and brain function as well as well-being, the validation of an animal model or paradigm to study the brain and central nervous system disorders is not complete without an evaluation of its implication on animal welfare...
March 15, 2016: Laboratory Animals
M C Gordijn, D G Beersma, A L Bouhuys, H J Korte, R H van den Hoofdakker
Unequivocal results demonstrating a causal relationship between a disturbance in circadian rhythms and depression have not yet been reported (reviews). However, acute mood changes, such as the antidepressive effect of sleep deprivation, diurnal variations of mood and their interrelationship, are commonly put forward as evidence of the importance of circadian dysregulations in affective disorders. The purpose of the present study is to obtain more insight in the mechanisms underlying these mood changes. The results will be discussed in the context of a recently postulated non-chronobiological explanation...
June 1995: Acta Neuropsychiatrica
A Wirz-Justice, K Kräuchi, D P Brunner, P Graw, H J Haug, G Leonhardt, A Sarrafzadeh, J English, J Arendt
Seasonal affective disorder (SAD) is characterised by recurrent episodes in autumn and winter of depression, hypersomnia, augmented appetite with carbohydrate craving, and weight gain, and can be successfully treated with bright light. Circadian rhythm hypotheses (summarized in) have stimulated research into the pathophysiology of SAD, postulating that: 1.The illness is a consequence of delayed phase position, 2.It is correlated with diminished circadian amplitude, or 3.It results from changes in the nocturnal duration between dusk and dawn e...
June 1995: Acta Neuropsychiatrica
Konrad S Jankowski
BACKGROUND: The study aimed to elucidate previously observed associations between morningness-eveningness and depressive symptomatology in university students. Relations between components of depressive symptomatology and morningness-eveningness were analysed. METHODS: Nine hundred and seventy-four university students completed Polish versions of the Centre for Epidemiological Studies - Depression scale (CES-D; Polish translation appended to this paper) and the Composite Scale of Morningness...
May 15, 2016: Journal of Affective Disorders
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