Dim Light at Night Induced Neurodegeneration and Ameliorative Effect of Curcumin

It is a well-known fact that following a proper routine light/dark or diurnal rhythm controls almost all biological processes. With the introduction of modern lighting and artificial illumination systems, continuous exposure to light at night may lead to the disruption of diurnal rhythm. However, the effect of light during the night on brain anatomy, physiology, and human body functions is less explored and poorly understood. In this study, we have evaluated the effect of exposure to dim light (5 lux) at night (dLAN) on Swiss Albino mice over a duration of three consecutive weeks. Results have revealed that exposure to dLAN led to an impairment of cognitive and non-cognitive behaviour, oxidative stress–mediated elevation of lipid peroxidation, and reduction of superoxide dismutase and catalase activity. It also led to the downregulation of hippocampal proteins (BDNF, Synapsin II and DCX) at both protein and mRNA level. Additionally, there was downregulation of CREB and SIRT1 mRNAs and neurodegeneration-associated miRNA21a-5p and miRNA34a-5p. The pyramidal and cortical neurons started showing pyknotic and chromatolysis characteristics. However, a dose of curcumin administered to the mice positively modulated these parameters in our experimental animals. We proposed the modulatory role of curcumin in addressing the deleterious effects of dLAN.

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Limited evidence for affective and diurnal rhythm responses to dim light-at-night in male and female C57Bl/6 mice

Physiology & Behavior ◽

10.1016/j.physbeh.2018.03.010 ◽

2018 ◽

Vol 189 ◽

pp. 78-85 ◽

Cited By ~ 6

Author(s):

Michael Cleary-Gaffney ◽

Andrew N. Coogan

Keyword(s):

Diurnal Rhythm ◽

Limited Evidence ◽

Light At Night ◽

Male And Female ◽

Dim Light

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Plasma melatonin and insulin-like growth factor-1 responses to dim light at night in dairy heifers

Journal of Pineal Research ◽

10.1111/j.1600-079x.2005.00303.x ◽

2006 ◽

Vol 40 (3) ◽

pp. 225-229 ◽

Cited By ~ 13

Author(s):

P. Muthuramalingam ◽

A. D. Kennedy ◽

R. J. Berry

Keyword(s):

Growth Factor ◽

Insulin Like Growth Factor ◽

Light At Night ◽

Dairy Heifers ◽

Plasma Melatonin ◽

Dim Light

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Cellular migration patterns in the developing mouse cerebral cortex

Development ◽

10.1242/dev.110.3.713 ◽

1990 ◽

Vol 110 (3) ◽

pp. 713-732 ◽

Cited By ~ 1

Author(s):

C.P. Austin ◽

C.L. Cepko

Keyword(s):

Cortical Neurons ◽

Intermediate Zone ◽

Cellular Migration ◽

Three Dimensions ◽

Cortical Plate ◽

Cortical Cells ◽

Migration Patterns ◽

Embryonic Mouse ◽

Radial Migration ◽

Almost All

The migration patterns of embryonic mouse cortical cells were investigated using a replication-incompetent retrovirus vector (BAG). The lateral ventricles of embryonic day 12 mouse embryos were infected with BAG and brains were harvested 2, 3, 4 and 6 days after infection. The location and morphology of all infected cortical cells were recorded from serial sections of entire brains, which were then reconstructed in three dimensions. Examination of the distribution of labelled cells revealed that there were migration patterns characteristic of each medial-lateral domain of the cortex. In the medial and dorsal areas, migration was often radial, although tangential spread increased with survival time, in large part due to ramification of cells in the intermediate zone. In the dorsolateral and lateral areas of the cortex, radial migration was generally not observed. Rather, variable extents of tangential migration occurred, and often resulted in wide separation of cells in the cortical plate. Almost all of the cellular dispersion occurred in the intermediate zone, although a modest degree of dispersion also occurred within the cortical plate itself. Most dispersion occurred in the mediolateral plane, with relatively little dispersion along the anteroposterior axis. Though characteristic migration patterns could be defined, wide variability in the extents of radial migration and tangential separation of cells was seen. The patterns of migration paralleled the distribution of radial glial fibers in all areas, and are most likely a reflection of the role of this network in supporting the migration of cortical neurons. The extent and variability of cellular dispersion supports a lineage-independent mechanism of cortical column ontogenesis.

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Dim Light at Night Exposure Induces Cold Hyperalgesia and Mechanical Allodynia in Male Mice

Neuroscience ◽

10.1016/j.neuroscience.2020.03.022 ◽

2020 ◽

Vol 434 ◽

pp. 111-119 ◽

Cited By ~ 2

Author(s):

Jacob R. Bumgarner ◽

William H. Walker ◽

Jennifer A. Liu ◽

James C. Walton ◽

Randy J. Nelson

Keyword(s):

Mechanical Allodynia ◽

Male Mice ◽

Light At Night ◽

Cold Hyperalgesia ◽

Dim Light

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Dim light at night interacts with intermittent hypoxia to alter cognitive and affective responses

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00100.2013 ◽

2013 ◽

Vol 305 (1) ◽

pp. R78-R86 ◽

Cited By ~ 9

Author(s):

Taryn G. Aubrecht ◽

Zachary M. Weil ◽

Ulysses J. Magalang ◽

Randy J. Nelson

Keyword(s):

Intermittent Hypoxia ◽

Dendritic Morphology ◽

Affective Responses ◽

Avoidance Task ◽

Cognitive Responses ◽

Spine Density ◽

Light At Night ◽

Lighting Condition ◽

Obstructive Sleep ◽

Dim Light

Obstructive sleep apnea (OSA) and dim light at night (dLAN) have both been independently associated with alterations in mood and cognition. We aimed to determine whether dLAN would interact with intermittent hypoxia (IH), a condition characteristic of OSA, to alter the behavioral, cognitive, and affective responses. Adult male mice were housed in either standard lighting conditions (14:10-h light-dark cycle; 150 lux:0 lux) or dLAN (150 lux:5 lux). Mice were then exposed to IH (15 cycles/h, 8 h/day, FiO2 nadir of 5%) for 3 wk, then tested in assays of affective and cognitive responses; brains were collected for dendritic morphology and PCR analysis. Exposure to dLAN and IH increased anxiety-like behaviors, as assessed in the open field, elevated plus maze, and the light/dark box. dLAN and IH increased depressive-like behaviors in the forced swim test. IH impaired learning and memory performance in the passive avoidance task; however, no differences were observed in spatial working memory, as assessed by y-maze or object recognition. IH combined with dLAN decreased cell body area in the CA1 and CA3 regions of the hippocampus. Overall, IH decreased apical spine density in the CA3, whereas dLAN decreased spine density in the CA1 of the hippocampus. TNF-α gene expression was not altered by IH or lighting condition, whereas VEGF expression was increased by dLAN. The combination of IH and dLAN provokes negative effects on hippocampal dendritic morphology, affect, and cognition, suggesting that limiting nighttime exposure to light in combination with other established treatments may be of benefit to patients with OSA.

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Dim Light at Night Exaggerates Weight Gain and Inflammation Associated With a High-Fat Diet in Male Mice

Endocrinology ◽

10.1210/en.2013-1121 ◽

2013 ◽

Vol 154 (10) ◽

pp. 3817-3825 ◽

Cited By ~ 66

Author(s):

Laura K. Fonken ◽

Rebecca A. Lieberman ◽

Zachary M. Weil ◽

Randy J. Nelson

Keyword(s):

Weight Gain ◽

High Fat Diet ◽

Male Mice ◽

High Fat ◽

Light At Night ◽

Dim Light

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hMEF2C gene encodes skeletal muscle- and brain-specific transcription factors.

Molecular and Cellular Biology ◽

10.1128/mcb.13.4.2564 ◽

1993 ◽

Vol 13 (4) ◽

pp. 2564-2577 ◽

Cited By ~ 142

Author(s):

J C McDermott ◽

M C Cardoso ◽

Y T Yu ◽

V Andres ◽

D Leifer ◽

...

Keyword(s):

Skeletal Muscle ◽

Transcription Factors ◽

Cortical Neurons ◽

Myogenic Differentiation ◽

Mrna Level ◽

Functional Characterization ◽

Essential Element ◽

Specific Pattern ◽

Cdna Clones ◽

Tissue Specific

The myocyte enhancer-binding factor 2 (MEF2) site is an essential element of many muscle-specific enhancers and promoters that binds nuclear proteins from muscle and brain. Recently, we have cloned a family of MEF2 transcription factors produced by two genes that, at the mRNA level, are broadly expressed and produce tissue-specific isoforms by posttranscriptional processes (Y.-T. Yu, R. E. Breitbart, L. B. Smoot, Y. Lee, V. Mahdavi, and B. Nadal-Ginard, Genes Dev. 6:1783-1798, 1992). Here, we report the isolation and functional characterization of cDNA clones encoding four MEF2 factors derived from a separate gene that we have named hMEF2C. In contrast to those of the previously reported genes, the transcripts of the hMEF2C gene are restricted to skeletal muscle and brain. One of the alternate exons is exclusively present in brain transcripts. The products of this gene have DNA-binding and trans-activating activities indistinguishable from those of the previously reported MEF2 factors. The hMEF2C gene is induced late during myogenic differentiation, and its expression is limited to a subset of cortical neurons. The potential targets for this transcription factor in a subset of neurons are not known at this time. The strict tissue-specific pattern of expression of hMEF2C in comparison with the more ubiquitous expression of other MEF2 genes suggests a different mode of regulation and a potentially important role of hMEF2C factors in myogenesis and neurogenesis.

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