Search our Database of Scientific Publications and Authors

I’m looking for a
    Rest-activity circadian rhythms in aged Nothobranchius korthausae. The effects of melatonin.
    Exp Gerontol 2013 May 4;48(5):507-16. Epub 2013 Mar 4.
    Department of Physiology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain.
    Adult (48-week-old) and senescent (72-week-old) individually-kept Nothobranchius korthausae were used as experimental subjects to characterise circadian system (CS) function and age-related changes in senescent fish. This species was specifically chosen because it has already shown potential for use as a model system in gerontological studies. The rest-activity rhythm (RAR) in fish can be easily monitored and used to characterise the state of the CS, and it has also been proposed as a reliable model to study sleep-like periods in fish. As they aged, N. korthausae experienced a significant decrease in total daily activity and a progressive impairment of the RAR, accompanied by changes in the regularity, fragmentation and amplitude of the rhythm. The ability of the CS to oscillate autonomously when the two main synchronizers, photoperiod and feeding time, were absent (continuous darkness and random feeding), was also impaired with age, as the capacity to re-synchronise to the light-dark (LD) cycle declined. Melatonin treatment improved the regularity, fragmentation and amplitude of the RAR in senescent fish, and it also improved sleep efficiency. In conclusion, N. korthausae represents a viable model for studying the aging of the circadian system and the restorative effect of chronobiotic substances, such as melatonin.

    Similar Publications

    Age-related changes in fatty acid profile and locomotor activity rhythms in Nothobranchius korthausae.
    Exp Gerontol 2011 Dec 28;46(12):970-8. Epub 2011 Aug 28.
    Department of Physiology, University of Murcia, Spain.
    The life cycle of Nothobranchius korthausae, a Cyprinodontiformes fish, was studied in our laboratory to characterise the ageing process. Some morphological changes, such as spine curvature, skin colour, and fin and eye appearance are described. Growth and survival curves reflected a fast life cycle with rapid initial growth until 4weeks of age, after which the fish grew more slowly before reaching their final size in week 40. Read More
    Role of melatonin in the regulation of human circadian rhythms and sleep.
    J Neuroendocrinol 2003 Apr;15(4):432-7
    Center for Chronobiology, Psychiatric University Clinic, Wilhelm Kleinstrasse 27, CH-4025 Basel, Switzerland.
    The circadian rhythm of pineal melatonin is the best marker of internal time under low ambient light levels. The endogenous melatonin rhythm exhibits a close association with the endogenous circadian component of the sleep propensity rhythm. This has led to the idea that melatonin is an internal sleep "facilitator" in humans, and therefore useful in the treatment of insomnia and the readjustment of circadian rhythms. Read More
    Circadian activity rhythms during the last days of Nothobranchius rachovii's life: a descriptive model of circadian system breakdown.
    Chronobiol Int 2015 Apr 25;32(3):395-404. Epub 2014 Nov 25.
    Faculty of Biology, Department of Physiology, University of Murcia , Murcia , Spain and.
    Several studies have been performed to identify age-related changes in the circadian system (CS) but the impairment of the CS and its chronodisruption at the end of an organism life have not been studied in depth. Aging commonly affects the input pathways into the biological clock or restraints their processing, therefore simplifying the system output, the overt rhythms. The purpose of this work was to do a complete characterization of changes that occurs in the CS in the last stage of a vertebrate organism life and to develop tools able to detect in which moment of the last days of life is the animal, using an overt rhythm, the rest-activity rhythm (RAR). Read More
    Clinical perspectives for the use of melatonin as a chronobiotic and cytoprotective agent.
    Ann N Y Acad Sci 2005 Dec;1057:327-36
    Department of Physiology, Faculty of Medicine, University of Buenos Aires, Argentina.
    The circadian time system involves periodic gene expression at the cellular level, synchronized by a hierarchically superior structure located in the hypothalamic suprachiasmatic nuclei. Treatment of circadian rhythm disorders has led to the development of a new type of agent called "chronobiotics," among which melatonin is the prototype. In elderly insomniacs, melatonin treatment decreased sleep latency and increased sleep efficiency, particularly slow-wave sleep. Read More