• Special Issue Topic

    Circadian Rhythm and Melatonin

    Submission Deadline: June 30, 2024

    Guest Editor

    Prof. Ertugrul Kilic E-Mail

    Head of Department of Physiology, Istanbul Medipol University, School of Medicine, Regenerative and Restorative Medical Research Center, Istanbul, Turkey

    Research Keywords: Stroke, spinal cord injury, cell signaling, brain plasticity

    About the Special Issue

    Circadian rhythm is driven by a master clock system within the suprachiasmatic nucleus of the hypothalamus, which regulates melatonin secretion and the circadian clock machinery. This circadian clock consists of self-sustained molecular clockwork which is regulated by the transcriptional activators Bmal1 and Circadian Locomotor Output Cycles Kaput Protein (Clock), and transcriptional repressors Cryptochrome Circadian Regulator 1 (Cry1), Cryptochrome Circadian Regulator 2 (Cry2), Period 1 (Per1), and Period 2 (Per2). Heterodimeric transcription factor Clock and Bmal1 activates enhancer box (E-Box), and both Per and Cry, which create a negative feedback loop of this circadian clock machinery in all cells in our body. Furthermore, other clock proteins such as Rev-Erb and Ror are also part of this cellular clock system. Discoveries of the molecular mechanisms of this system were also awarded with the Nobel Prize in 2017.

    In the physiological conditions, melatonin and other circadian rhythm proteins regulate many functions, including sleep-wake cycle, behaviour, and many metabolic functions. However, in recent decades, the role of these molecules has been investigated in the disease conditions such as neurodegenerative disorders. It was shown that indolamine melatonin protects the brain in many neurodegenerative diseases with its direct antioxidant activity and indirectly via its effect on survival kinases. In addition, the role of circadian clock proteins in the function of the brain has been implicated both in the physiological and pathological conditions. An example for this, the absence of Bmal1 protein plays an essential role in the prognosis of Alzheimer's Disease and stroke.

    In this special issue “Circadian Rhythm and Melatonin”, we expect to focus on the role of circadian rhythm and melatonin in the physiological brain function and pathophysiological events after neurodegenerative disorders. 

    Keywords: Bmal1, cell signaling, circadian rhythm, clock, free radicals, melatonin, Per1, pineal gland, Rev-Erb

    Call for Papers

    Published Articles

    Open Access
    Current state of knowledge on the centrifugal visual system (including the pinealo-to-retinal connection) in mammals and its hypothesized role in circadian rhythms
    The ubiquity of circadian rhythms in living organisms has generally been accepted by researchers over the last century. Indeed, morphology and molecular biology of the circadian clock were described [...] Read more.
    Viktória Vereczki ... Ágnes Csáki
    Published: February 22, 2024 Explor Neurosci. 2024;3:51–64
    DOI: https://doi.org/10.37349/en.2024.00036
    Times Cited: 0
    Open Access
    Neuropharmacologic modulation of the melatonergic system
    The circadian rhythm is a critical system that governs an organism’s functions in alignment with the light-dark cycle. Melatonin release from the pineal gland plays a crucial role in regulating th [...] Read more.
    Utku Aykan ... Canan Uluoglu
    Published: December 22, 2023 Explor Neurosci. 2023;2:287–306
    DOI: https://doi.org/10.37349/en.2023.00029
    Open Access
    Circadian regulation of the immune-hematopoietic system
    Earth’s rotation generates the basic circadian rhythm of day and night to which all living organisms must adapt to survive. In mammals, this happens thanks to a central clock located in the suprac [...] Read more.
    Georges Maestroni
    Published: June 30, 2023 Explor Neurosci. 2023;2:123–139
    DOI: https://doi.org/10.37349/en.2023.00017
    Open Access
    Impact of circadian clock dysfunction on human health
    All living organisms exhibit circadian rhythms. Humans show circadian rhythm of the different physiological functions such as sleep-wake cycle, core body temperature, feeding behavior, metabolic act [...] Read more.
    Saptadip Samanta, Sk Asif Ali
    Published: September 29, 2022 Explor Neurosci. 2022;1:4–30
    DOI: https://doi.org/10.37349/en.2022.00002