Scientists provide first evidence that carbamates can upset circadian rhythms

 The current research focuses on two chemicals, carbaryl, the third most widely used insecticide in the U.S. but which is illegal in several countries, and carbofuran, the most toxic carbamate insecticide, which has been banned for applications on food crops for human consumption since 2009. It is still used in many countries, including Mexico and traces persist in food, plants and wildlife.
"We found that both insecticides are structurally similar to melatonin and that both showed affinity for the melatonin, MT2 receptors, that can potentially affect glucose homeostasis and insulin secretion," said Marina Popovska-Gorevski, co-author, now a scientist with Boehringer Ingelheim Pharmaceuticals, who worked in Dubocovich's lab while earning her master's degree at UB. "That means that exposure to them could put people at higher risk for diabetes and also affect sleeping patterns.""

Gut Microbes Influence Circadian Clock | The Scientist Magazine®

The mammalian gut microbiome is involved in controlling the circadian
rhythm of its host, according to a mouse study published today (April
16) in Cell Host & Microbe. In both mice and humans, timing of feeding and diet type can impact the bacterial populations of the gut. Now, Eugene Chang
of the University of Chicago Medical Center and his colleagues have
found that mouse gut microbiota produce metabolites in diurnal patterns,
and these can influence the expression of circadian clock genes in the
liver.
The results provide additional support for the idea that the gut microbiome is dynamic, said Satchidananda Panda
of the Salk Institute for Biological Studies who was not involved in
the work. “At night, we go to bed with a bunch of bugs in our stomachs
and wake up in the morning with a different set of bugs,” said Panda.
“The implications are pretty big because there are more bacterial cells
in our guts than the number of cells in our body and these species
produce different enzymes and factors that have a big impact on our
overall metabolism.”

Want a good night's sleep in the New Year? Quit smoking

As if cancer, heart disease and other diseases were not enough motivation to make quitting smoking your New Year's resolution, here's another wake-up call: New research published in the January 2014 issue of The FASEB Journal suggests that smoking disrupts the circadian clock function in both the lungs and the brain. Translation: Smoking ruins productive sleep, leading to cognitive dysfunction, mood disorders, depression and anxiety.

Why eating at the wrong times is tied to such profound and negative effects on our bodies The Scientist Magazine®

Few environmental factors are as reliable as the 24-hour day, and an evolutionary argument can be made for why the diurnal rhythms of the Earth’s rotation are so coupled with human metabolism. Our behavior, our physiology, and our biochemistry reflect the daily cycles of the planet, and people who fall out of sync with these cycles are more likely to suffer from diabetes, obesity, and heart disease. Gastrointestinal disorders, depression, and other ailments are also more common among people who don’t have normal sleep habits. But according to new research, it’s not just disrupted sleep that can lead to these myriad physiological symptoms; it’s also the altered patterns of food consumption that go along with keeping such strange hours.

JCI - Circadian clock proteins regulate neuronal redox homeostasis and neurodegeneration

Brain aging is associated with diminished circadian clock output and decreased expression of the core clock proteins, which regulate many aspects of cellular biochemistry and metabolism. The genes encoding clock proteins are expressed throughout the brain, though it is unknown whether these proteins modulate brain homeostasis. We observed that deletion of circadian clock transcriptional activators aryl hydrocarbon receptor nuclear translocator–like (Bmal1) alone, or circadian locomotor output cycles kaput (Clock) in combination with neuronal PAS domain protein 2 (Npas2), induced severe age-dependent astrogliosis in the cortex and hippocampus. Mice lacking the clock gene repressors period circadian clock 1 (Per1) and period circadian clock 2 (Per2) had no observed astrogliosis. Bmal1 deletion caused the degeneration of synaptic terminals and impaired cortical functional connectivity, as well as neuronal oxidative damage and impaired expression of several redox defense genes. Targeted deletion of Bmal1 in neurons and glia caused similar neuropathology, despite the retention of intact circadian behavioral and sleep-wake rhythms. Reduction of Bmal1 expression promoted neuronal death in primary cultures and in mice treated with a chemical inducer of oxidative injury and striatal neurodegeneration. Our findings indicate that BMAL1 in a complex with CLOCK or NPAS2 regulates cerebral redox homeostasis and connects impaired clock gene function to neurodegeneration.

How body clock affects inflammation: Discovery could accelerate body's response to infection, autoimmune disorders

 "The study published in the Nov. 8 edition of Science identifies a previously hidden pathway by which the body's circadian clock controls the numbers of key inflammatory cells called interleukin-17-producing CD4+ T helper cells (TH17). The work could lead to new ways to rev up the body's immune response to infection or dampen that response in the case of autoimmune diseases in which the body attacks its own tissues, said senior author Dr. Lora Hooper, Professor of Immunology and Microbiology and a Howard Hughes Medical Institute (HHMI) Investigator."

Brain may flush out toxins during sleep

A good night’s rest may literally clear the mind. Using mice, researchers showed for the first time that the space between brain cells may increase during sleep, allowing the brain to flush out toxins that build up during waking hours. These results suggest a new role for sleep in health and disease. Their results, published in Science, show that during sleep a plumbing system called the glymphatic system may open, letting fluid flow rapidly through the brain. Dr. Nedergaard’s lab recently discovered the glymphatic system helps control the flow of cerebrospinal fluid (CSF), a clear liquid surrounding the brain and spinal cord.

Observing live gene expression in the body

 "Most of our physiological functions fluctuate throughout the day. They are coordinated by a central clock in the brain and by local oscillators, present in virtually every cell. Many molecular gearwheels of this internal clock have been described by Ueli Schibler, professor at the Faculty of Science of the University of Geneva (UNIGE), Switzerland. To study how the central clock synchronizes subordinate oscillators, the researcher's group used a variety of genetic and technological tools developed in collaboration with a team of UNIGE physicians. In this way, the scientists were able to directly observe the bioluminescence emitted by 'clock genes' in mice for several months. This biotechnology is applicable to numerous sectors of biomedical research, which attracted the attention of the editors from the journal Genes & Development."

Circadian rhythms control body's response to intestinal infections

In tests on mice infected with salmonella, the researchers noted that circadian-controlled genes govern the immune response to the invading pathogen, leading to day-night differences in infection potential and in the immune system's ability to deal with pathogens.

Geographic Variation in the Prevalence of Attention-Deficit/Hyperactivity Disorder: The Sunny Perspective.

Attention-deficit/hyperactivity disorder (ADHD) is the most common psychiatric disorder of childhood, with average worldwide prevalence of 5.3%, varying by region.

METHODS:

We assessed the relationship between the prevalence of ADHD and solar intensity (SI) (kilowatt hours/square meters/day) on the basis of multinational and cross-state studies. Prevalence data for the U.S. were based on self-report of professional diagnoses; prevalence data for the other countries were based on diagnostic assessment. The SI data were obtained from national institutes.

RESULTS:

In three datasets (across 49 U.S. states for 2003 and 2007, and across 9 non-U.S. countries) a relationship between SI and the prevalence of ADHD was found, explaining 34%-57% of the variance in ADHD prevalence, with high SI having an apparent preventative effect. Controlling for low birth weight, infant mortality, average income (socioeconomic status), latitude, and other relevant factors did not change these findings. Furthermore, these findings were specific to ADHD, not found for the prevalence of autism spectrum disorders or major depressive disorder.

CONCLUSIONS:

In this study we found a lower prevalence of ADHD in areas with high SI for both U.S. and non-U.S. data. This association has not been reported before in the literature. The preventative effect of high SI might be related to an improvement of circadian clock disturbances, which have recently been associated with ADHD. These findings likely apply to a substantial subgroup of ADHD patients and have major implications in our understanding of the etiology and possibly prevention of ADHD by medical professionals, schools, parents, and manufacturers of mobile device

Circadian patterns of gene expression in the human brain and disruption in major depressive disorder

A cardinal symptom of major depressive disorder (MDD) is the disruption of circadian patterns. However, to date, there is no direct evidence of circadian clock dysregulation in the brains of patients who have MDD. Circadian rhythmicity of gene expression has been observed in animals and peripheral human tissues, but its presence and variability in the human brain were difficult to characterize. Here, we applied time-of-death analysis to gene expression data from high-quality postmortem brains, examining 24-h cyclic patterns in six cortical and limbic regions of 55 subjects with no history of psychiatric or neurological illnesses (“controls”) and 34 patients with MDD. Our dataset covered ∼12,000 transcripts in the dorsolateral prefrontal cortex, anterior cingulate cortex, hippocampus, amygdala, nucleus accumbens, and cerebellum. Several hundred transcripts in each region showed 24-h cyclic patterns in controls, and >100 transcripts exhibited consistent rhythmicity and phase synchrony across regions. Among the top-ranked rhythmic genes were the canonical clock genes BMAL1(ARNTL), PER1-2-3, NR1D1(REV-ERBa), DBP, BHLHE40 (DEC1), andBHLHE41(DEC2). The phasing of known circadian genes was consistent with data derived from other diurnal mammals. Cyclic patterns were much weaker in the brains of patients with MDD due to shifted peak timing and potentially disrupted phase relationships between individual circadian genes. This transcriptome-wide analysis of the human brain demonstrates a rhythmic rise and fall of gene expression in regions outside of the suprachiasmatic nucleus in control subjects. The description of its breakdown in MDD suggests potentially important molecular targets for treatment of mood disorders.

Luminous Bacteria Control Clock Genes In Host's Body

MNY: Another new study takes a further step toward revealing the pervasive influence microbial communities that inhabit plants and animals have on their biology. Scientists in the US have discovered that the luminous bacterium Vibrio fischeri regulates the daily rhythm of its host, the Hawaiian bobtail squid, by interacting with its clock genes. "

Our internal clocks can become ticking time bombs for diabetes and obesity

"If you're pulling and all-nighter to finish a term paper, a new parent up all night with a fussy baby, or simply can't sleep like you once could, then you may be snoozing on good health. That's because new research published in The FASEB Journal used mice to show that proper sleep patterns are critical for healthy metabolic function, and even mild impairment in our circadian rhythms can lead to serious health consequences, including diabetes and obesity."


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Futurity.org – Why bodies store fat when we eat at night

Insulin activity is controlled by the body’s circadian clock, which helps explain why not only what you eat, but when you eat, matters.

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Circadian rhythms can be modified for potential treatment of disorders | UCIrvine News

UC Irvine-led studies have revealed the cellular mechanism by which circadian rhythms – also known as the body clock – modify energy metabolism and also have identified novel compounds that control this action. The findings point to potential treatments for disorders triggered by circadian rhythm dysfunction, ranging from insomnia and obesity to diabetes and cancer.

Aberrant light directly impairs mood and learning through melanopsin-expressing neurons : Nature : Nature Publishing Group

The daily solar cycle allows organisms to synchronize their circadian rhythms and sleep–wake cycles to the correct temporal niche. Changes in day-length, shift-work, and transmeridian travel lead to mood alterations and cognitive function deficits Sleep deprivation and circadian disruption underlie mood and cognitive disorders associated with irregular light schedules Whether irregular light schedules directly affect mood and cognitive functions in the context of normal sleep and circadian rhythms remains unclear. Here we show, using an aberrant light cycle that neither changes the amount and architecture of sleep nor causes changes in the circadian timing system, that light directly regulates mood-related behaviours and cognitive functions in mice. Animals exposed to the aberrant light cycle maintain daily corticosterone rhythms, but the overall levels of corticosterone are increased. Despite normal circadian and sleep structures, these animals show increased depression-like behaviours and impaired hippocampal long-term potentiation and learning. Administration of the antidepressant drugs fluoxetine or desipramine restores learning in mice exposed to the aberrant light cycle, suggesting that the mood deficit precedes the learning impairments. To determine the retinal circuits underlying this impairment of mood and learning, we examined the behavioural consequences of this light cycle in animals that lack intrinsically photosensitive retinal ganglion cells. In these animals, the aberrant light cycle does not impair mood and learning, despite the presence of the conventional retinal ganglion cells and the ability of these animals to detect light for image formation. These findings demonstrate the ability of light to influence cognitive and mood functions directly through intrinsically photosensitive retinal ganglion cells.

GEN | News Highlights:Gene Predicts Time of Death

A common variant in the perion gene PER1 separates early birds from night owls, and can even predict someone’s hour of death.

The findings—published in the November issue of the journal Annals of Neurology—could help people schedule anything from work to medical treatments, while offering clues to the conditions of vulnerable patients.

Could poor sleep contribute to symptoms of schizophrenia?

Neuroscientists studying the link between poor sleep and schizophrenia have found that irregular sleep patterns and desynchronised brain activity during sleep could trigger some of the disease's symptoms. The findings, published in the journal Neuron, suggest that these prolonged disturbances might be a cause and not just a consequence of the disorder's debilitating effects.

Read more at: http://medicalxpress.com/news/2012-11-poor-contribute-symptoms-schizophrenia.html#jCp

It's not just what you eat, but when you eat it

Fat cells store excess energy and signal these levels to the brain. In a new study this week in Nature Medicine, Georgios Paschos PhD, a research associate in the lab of Garret FitzGerald, MD, FRS director of the Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, shows that deletion of the clock gene Arntl, also known as Bmal1, in fat cells, causes mice to become obese, with a shift in the timing of when this nocturnal species normally eats. These findings shed light on the complex causes of obesity in humans.

Read more at: http://medicalxpress.com/news/2012-11-it-not-just-what-you.html#jCp

Chronic exposure to dim light may raise depression risk

Two years ago, Randy Nelson, Ph.D., chair of neuroscience at Ohio State University, doctoral student Tracy Bedrosian, and colleagues reported that dim-light exposure at night was capable of triggering depressive-like behaviors in animals. The dim-light exposure, they explained, was comparable to having a television on in a darkened room.

Read more at: http://medicalxpress.com/news/2012-09-chronic-exposure-dim-depression.html#jCp