Effects of light on human circadian rhythms, sleep and mood

Somnologie - Schlafforschung und Schlafmedizin, Journal Year: 2019, Volume and Issue: 23(3), P. 147 - 156

Published: Aug. 20, 2019

Humans live in a 24-hour environment, which light and darkness follow diurnal pattern. Our circadian pacemaker, the suprachiasmatic nuclei (SCN) hypothalamus, is entrained to solar day via pathway from retina synchronises our internal biological rhythms. Rhythmic variations ambient illumination impact behaviours such as rest during sleep activity wakefulness well their underlying processes. Rather recently, availability of artificial has substantially changed especially evening night hours. This may increase risk developing rhythm sleep-wake disorders (CRSWD), are often caused by misalignment endogenous rhythms external light-dark cycles. While exact relationship between CRSWD remains be established, nocturnal been shown alter humans. On other hand, can also used an effective noninvasive therapeutic option with little no side effects, improve sleep,mood general well-being. article reviews current state knowledge regarding effects on rhythms, sleep, mood.

Language: Английский

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LEDs for photons, physiology and food

Nature, Journal Year: 2018, Volume and Issue: 563(7732), P. 493 - 500

Published: Nov. 1, 2018

Language: Английский

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Human melanopsin forms a pigment maximally sensitive to blue light ( λ _max ≈ 479 nm) supporting activation of G _{q /11} and G _i/o signalling cascades

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2013, Volume and Issue: 280(1759), P. 20122987 - 20122987

Published: April 3, 2013

A subset of mammalian retinal ganglion cells expresses an opsin photopigment (melanopsin, Opn4) and is intrinsically photosensitive. The human retina contains melanopsin, but the literature lacks a direct investigation its spectral sensitivity or G-protein selectivity. Here, we address this deficit by studying physiological responses driven melanopsin under heterologous expression in HEK293 cells. Luminescent reporters for common second messenger systems revealed that light induces high amplitude increase intracellular calcium modest reduction cAMP expressing implying pigment able to drive via both G q i/o class G-proteins. Melanopsins from mouse amphioxus had similar profile coupling cells, chicken Opn4m Opn4x pigments exhibited some s activity addition strong /11 response. An action spectrum response predicted form : vitamin A1 peaked at 479 nm. selectivity previously described rodents, supporting utility such laboratory animals developing methods manipulating system using pharmacological agents.

Language: Английский

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Form and Function of the M4 Cell, an Intrinsically Photosensitive Retinal Ganglion Cell Type Contributing to Geniculocortical Vision

Journal of Neuroscience, Journal Year: 2012, Volume and Issue: 32(39), P. 13608 - 13620

Published: Sept. 26, 2012

The photopigment melanopsin confers photosensitivity upon a minority of retinal output neurons. These intrinsically photosensitive ganglion cells (ipRGCs) are more diverse than once believed, comprising five morphologically distinct types, M1 through M5. Here, in mouse retina, we provide the first in-depth characterization M4 cells, including their structure, function, and central projections. apparently correspond to ON α earlier reports, easily distinguished from other ipRGCs by very large somata. Their dendritic arbors radiate highly branched those M1, M2, or M3 cells. melanopsin-based intrinsic photocurrents smaller M2 presumably because is weakly expressed; can detect it immunohistochemically only with strong amplification. Like exhibit robust, sustained, synaptically driven responses stratification sublamina inner plexiform layer. However, patterns subtly different, dendrites positioned just distal proximal cholinergic band. receptive fields large, an center, antagonistic OFF surround nonlinear spatial summation. photoresponses lack direction selectivity show higher ultraviolet sensitivity ventral retina dorsal echoing topographic gradient S- M-cone opsin expression. readily labeled retrograde transport lateral geniculate nucleus thus likely contribute pattern vision that persists mice lacking functional rods cones.

Language: Английский

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Melanopsin and the Intrinsically Photosensitive Retinal Ganglion Cells: Biophysics to Behavior

Neuron, Journal Year: 2019, Volume and Issue: 104(2), P. 205 - 226

Published: Oct. 1, 2019

Language: Английский

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Restoring the ON Switch in Blind Retinas: Opto-mGluR6, a Next-Generation, Cell-Tailored Optogenetic Tool

PLoS Biology, Journal Year: 2015, Volume and Issue: 13(5), P. e1002143 - e1002143

Published: May 7, 2015

Photoreceptor degeneration is one of the most prevalent causes blindness. Despite photoreceptor loss, inner retina and central visual pathways remain intact over an extended time period, which has led to creative optogenetic approaches restore light sensitivity in surviving retina. The major drawbacks all tools recently developed tested mouse models are their low lack physiological compatibility. Here we introduce a next-generation tool, Opto-mGluR6, designed for retinal ON-bipolar cells, overcomes these limitations. We show that chimeric protein consisting intracellular domains cell–specific metabotropic glutamate receptor mGluR6 light-sensing melanopsin, reliably recovers vision at retinal, cortical, behavioral levels under moderate daylight illumination.

Language: Английский

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Colour As a Signal for Entraining the Mammalian Circadian Clock

PLoS Biology, Journal Year: 2015, Volume and Issue: 13(4), P. e1002127 - e1002127

Published: April 17, 2015

Twilight is characterised by changes in both quantity ("irradiance") and quality ("colour") of light. Animals use the variation irradiance to adjust their internal circadian clocks, aligning behaviour physiology with solar cycle. However, it currently unknown whether colour also contribute this entrainment process. Using environmental measurements, we show here that mammalian blue–yellow discrimination provides a more reliable method tracking twilight progression than simply measuring irradiance. We next electrophysiological recordings demonstrate neurons mouse suprachiasmatic clock display cone-dependent spectral opponency required make information. Thus, our data some are highly sensitive composition occurring over input dictates response Finally, using mice housed under photoperiods simulated dawn/dusk transitions, confirm during for appropriate alignment natural conditions. Together, these reveal new sensory mechanism telling time day would be available any species capable chromatic vision.

Language: Английский

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Standards in Pupillography

Frontiers in Neurology, Journal Year: 2019, Volume and Issue: 10

Published: Feb. 21, 2019

The number of research groups studying the pupil is increasing, as publications. Consequently, new standards in pupillography are needed to formalize methodology including recording conditions, stimulus characteristics, well suitable parameters evaluation. Since description intrinsically photosensitive retinal ganglion cells (ipRGCs) there has been an increased interest and broader application ophthalmology other fields psychology chronobiology. Colour plays important role not only but also clinical observational therapy studies like gene hereditary degenerations psychopathology. Stimuli can vary size, brightness, duration, wavelength. Stimulus paradigms determine whether rhodopsin-driven rod responses, opsin-driven cone or melanopsin-driven ipRGC responses primarily elicited. Background illumination, adaptation state, instruction for participants will furthermore influence results. This standard recommends a minimum set variables be used specified publication methodologies. Initiated at 32nd International Pupil Colloquium 2017 Morges, Switzerland, aim this manuscript outline based on current knowledge experience experts order achieve greater comparability pupillographic studies. Such particularly facilitate proper by researchers field. First we describe general standards, followed specific suggestions concerning demands different targets research: afferent efferent reflex arc, pharmacology, psychology, sleepiness-related animal

Language: Английский

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Intrinsically Photosensitive Retinal Ganglion Cells of the Human Retina

Frontiers in Neurology, Journal Year: 2021, Volume and Issue: 12

Published: March 25, 2021

Light profoundly affects our mental and physical health. In particular, light, when not delivered at the appropriate time, may have detrimental effects. mammals, light is perceived only by rods cones but also a subset of retinal ganglion cells that express photopigment melanopsin renders them intrinsically photosensitive (ipRGCs). ipRGCs participate in contrast detection play critical roles non-image-forming vision, set responses include circadian entrainment, pupillary reflex (PLR), modulation sleep/alertness, mood. are found human retina, their response to has been characterized indirectly through suppression nocturnal melatonin PLR. However, until recently, had rarely investigated directly. This gap progressively being filled as, over last years, an increasing number studies provided descriptions morphology, gene expression. Here, I review progress knowledge ipRGCs, different morphological functional subtypes described so far how they match murine subtypes. highlight questions remain be addressed. Investigating as these few major role well-being. Additionally, display increased vulnerability or resilience certain disorders compared conventional RGCs, deeper function could help identify therapeutic approaches develop diagnostic tools. Overall, better understanding eye will deliver precise usage recommendations implement light-based interventions improve cognitive performance, mood, life quality.

Language: Английский

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Opponent melanopsin and S-cone signals in the human pupillary light response

Proceedings of the National Academy of Sciences, Journal Year: 2014, Volume and Issue: 111(43), P. 15568 - 15572

Published: Oct. 13, 2014

Significance Our eyes sense bright light using cones (L, M, and S) recently discovered melanopsin-containing ganglion cells. Both S melanopsin respond to blueish (short-wavelength) light. How does interact with the in visual function? We measured response of human pupil isolated stimulation different photoreceptors. work reveals a curious, opponent blue otherwise familiar pupillary response. Increased can cause dilate, but this effect is usually masked by stronger opposite from results have clinical importance because sensing known be related seasonal depression, sleep, pain

Language: Английский

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