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Before bed may be the best time to take blood pressure meds, study suggests | MinnPost

“The same medication ingested at different times of the day actually has different pharmacological properties, behaving like totally different medications,” explained Ramón Hermida, the study’s lead author and a chronobiologist at the University of Vigo in Spain, in an interview with NBC News.

Scientists discover skin keeps time independent of the brain -- ScienceDaily

But, he said, this study found that the skin actually expresses its own photoreceptors using a previously mysterious member of the opsin gene family, neuroposin. This means that skin can sense whether it is day or night even when it's cultured by itself in a dish. "If you simulate taking the cultured skin from Seattle to Japan (by simulating the light changes across time zones), the skin figures out that the time zone has changed and adapts to the new time zone within days because of neuropsin," said co-author Russ Van Gelder, professor and chair of ophthalmology at the UW School of Medicine. .

Chronobiology: Sleep and synaptic rhythms -- ScienceDaily

In the second study published in the same issue of Science the same group, in collaboration with a group from the University of Zürich (Steve Brown), has showed that synaptic protein abundance is also rhythmically shaped by sleep-wake cycles. In particular, they demonstrated that synaptic activity triggers the cycling production of proteins from messenger molecules that rhythmically accumulate at the synapses across the day. While protein production completely depends on wake-sleep cycles, messenger molecules travel and accumulate in the synapses predominantly in response to circadian mechanisms.

Molecule links weight gain to gut bacteria -- ScienceDaily

The study also found that microbes program these so-called circadian rhythms by activating a protein named histone deacetylase 3 (HDAC3), which is made by cells that line the gut. Those cells act as intermediaries between bacteria that aid in digestion of food and proteins that enable absorption of nutrients. The study, done in mice, revealed that HDAC3 turns on genes involved in the absorption of fat. They found that HDAC3 interacts with the biological clock machinery within the gut to refine the rhythmic ebb and flow of proteins that enhance absorption of fat. This regulation occurs in the daytime in humans, who eat during the day, and at night in mice, which eat at night. "The microbiome actually communicates with our metabolic machinery to make fat absorption more efficient. But when fat is overabundant, this communication can result in obesity. Whether the same thing is going on in other mammals, including humans, is the subject of future studies," added lead author Dr. Zheng Kuang, a postdoctoral fellow in the Hooper laboratory.

Biological clock influences immune response efficiency -- ScienceDaily

"Our study shows that T cells are more prone to be activated at certain times of the day. Identifying the mechanisms through which the biological clock modulates the T cell response will help us better understand the processes that regulate optimal T cell responses. This knowledge will contribute to improving vaccination strategies and cancer immune therapies," states Nathalie Labrecque, Professor at the Departments of Medicine and Microbiology, Infectious Diseases and Immunology at Université de Montréal.

Insulin under the influence of light -- ScienceDaily

To better assess the effect of light on tissue sensitivity to insulin, researchers measured insulin-induced glucose absorption. It turns out that a small disturbance in photic inputs (e.g. an hour of light exposure in the middle of the dark cycle, or light removal for 2 days) is enough to cause a negative effect. Indeed, increased or decreased light exposure can profoundly influence the sensitivity of tissues to insulin and the alteration, however minimal, of this mechanism is sufficient to significantly disrupt metabolic homeostasis. This would explain why people exposed to light at the wrong time -- workers in shift patterns, for example -- are more likely to develop metabolic diseases (e.g. diabetes).

Dead zones in circadian clocks -- ScienceDaily

One of the important properties of circadian clocks is the response to light signals, which enables organisms to become entrained to the 24-hour light-dark cycle on Earth. It has been shown that circadian clocks respond to light signals during the night, whereas they do not respond to such signals during the daytime. This holds true even when an organism is kept in complete darkness; a short light pulse does not change the time of the circadian clock when body time of the individual is at daytime. The time period in which the circadian clock is insensitive to light signals is referred to as the "dead zone." Previous studies have indicated that the presence of a dead zone improves the robustness of the clock. However, the mechanism underlying its generation is unclear.

How eating feeds into the body clock -- ScienceDaily

Dr Priya Crosby, a researcher at the MRC LMB and lead author on the study, highlighted: "Our data suggests that eating at the wrong times could have a major impact on our circadian rhythms. There is still work to do here, but paying particular attention to meal timing and light exposure is likely the best way to mitigate the adverse effects of shift-work. Even for those who work more traditional hours, being careful about when we eat is an important way to help maintain healthy body clocks, especially as we age."

Study links fluorescent lighting to inflammation and immune response - Neuroscience News

“In this report, we show genome-wide changes of gene expression patterns in skin, brain and liver for two commonly utilized fish experimental models (zebrafish and Japanese rice fish, also known as medaka), and a mammalian (mice), following exposure to 4,100 K ‘cool-white’ fluorescent light,” Walter said. “In spite of the extreme divergence of these animals (i.e., estimated divergence of mice and fish about 450 million years), and drastically different lifestyles (i.e., diurnal fish and nocturnal mice), the same highly conserved primary genetic response that involves activation of inflammation and immune pathways as part of an overall acute phase response was observed in the skin, brain and liver of all three animals. Follow-up studies to further define this response in mice are underway.”

Morning exercise for optimal metabolic impact

They found that a protein called hypoxia-inducible factor 1-alpha (HIF-1α) plays an important role and that it is activated by exercise in different ways depending on the time of day. HIF-1α is a transcription factor that is known to stimulate certain genes based on oxygen levels in tissue. “It makes sense that HIF-1α would be important here, but until now we didn’t know that its levels fluctuate based on the time of day,” Sassone-Corsi says. “This is a new finding.” Based on the work from the UC Irvine team, exercise seemed to have the most beneficial impact on the metabolism at the beginning of the active phase phase (equivalent to late morning in humans) compared with the resting phase (evening).

Two studies explore whether time of day can affect the body's response to exercise - Neuroscience News

The researchers also studied 12 humans and found similar effects. Overall, the people in the study had lower oxygen consumption while exercising in the evening compared with the morning; this translated to better exercise efficiency.

Fat cells work different 'shifts' throughout the day -- ScienceDaily

During this unique study seven participants underwent regulated sleep-wake cycles and meal times before entering the laboratory, where they maintained this routine for a further three days. Participants then experienced a 37- hour 'constant routine' during which time they did not experience daily changes in light-dark, feed-fast and sleep-wake cycles. Biopsies of fat tissue were taken at six hourly intervals and then followed by an analysis of gene expression. Researchers identified 727 genes in the fat tissue that express their own circadian rhythm, many carrying out key metabolic functions. A clear separation in gene rhythms was identified with approximately a third peaking in the morning and two thirds in the evening.

Exercise in Morning or Afternoon to Shift Your Body Clock Forward – Neuroscience News

This study found that exercising at 7 am or between 1 and 4 pm advanced the body clock to an earlier time, and exercising between 7 and10 pm delayed the body clock to a later time. Exercising between 1 and 4 am and at 10 am, however, had little effect on the body clock, and the phase-shifting effects of exercise did not differ based on age nor gender.

Disrupted circadian rhythms may drive anxiety and exacerbate brain disorders

"The studies presented today help deepen our understanding of why sleep is disrupted in so many patients," said press conference moderator Clifford Saper, MD, Ph.D., of Harvard Medical School, who's work focuses on integrated functions maintained by hypothalamus which includes the regulation of wake-sleep cycles. "They also suggest that sleep-focused therapies, such as treatments to regulate circadian rhythms, may be beneficial in the prevention or treatment of a vast array of diseases, including Alzheimer's disease and anxiety disorder and furthermore emphasize the critical need of good sleep for everyone's health."

Brain clock ticks differently in autism -- ScienceDaily

Sensory areas of the brain that receive input from the eyes, skin and muscles usually have shorter processing periods compared with higher-order areas that integrate information and control memory and decision-making. The new study, published in the journal eLife on February 5, shows that this hierarchy of intrinsic neural timescales is disrupted in autism. Atypical information processing in the brain is thought to underlie the repetitive behaviors and socio-communicational difficulties seen across the spectrum of autistic neurodevelopmental disorders (ASD), but this is one of the first indications that small-scale temporal dynamics could have an outsized effect.

Heavy drinking may change DNA, leading to increased craving for alcohol: Genetic vicious cycle may reinforce risky drinking behavior -- ScienceDaily

Scientists at Rutgers and Yale University School of Medicine focused on two genes implicated in the control of drinking behavior: PER2, which influences the body's biological clock, and POMC, which regulates our stress-response system. By comparing groups of moderate, binge and heavy drinkers, the researchers found that the two genes had changed in the binge and heavy drinkers through an alcohol-influenced gene modification process called methylation. The binge and heavy drinkers also showed reductions in gene expression, or the rate at which these genes create proteins. These changes increased with greater alcohol intake. Additionally, in an experiment, the drinkers viewed stress-related, neutral or alcohol-related images. They also were shown containers of beer and subsequently tasted beer, and their motivation to drink was evaluated. The result: alcohol-fueled changes in the genes of binge and heavy drinkers were associated with a greater desire for alcohol.

How Fasting Can Improve Overall Health - Neuroscience News

“The reorganization of gene regulation by fasting could prime the genome to a more permissive state to anticipate upcoming food intake and thereby drive a new rhythmic cycle of gene expression. In other words, fasting is able to essentially reprogram a variety of cellular responses. Therefore, optimal fasting in a timed manner would be strategic to positively affect cellular functions and ultimately benefiting health and protecting against aging-associated diseases.”

Stephen Colbert Shares His Struggle With Anxiety and Why He Stopped Taking Xanax | Entertainment Tonight

"I was actually medicated," he says. "I mean, in the most common, prosaic way. Xanax was just lovely. Y’know, for a while. And then I realized that the gears were still smoking. I just couldn’t hear them anymore. But I could feel them, I could feel the gearbox heating up and smoke pouring out of me, but I was no longer walking around a couch." "I had a bit of a nervous breakdown after I got married -- kind of panic attacks," he continues. "My wife would go off to work and she’d come home -- because I worked at night -- and I’d be walking around the couch. And she’s like, 'How was your day?' And I’d say, 'You’re looking at it.' Just tight circles around the couch."

Light pollution may cause insomnia in older adults: Artificial, outdoor light exposure at night is significantly associated with hypnotic drug prescription -- ScienceDaily

Results show that increasing nighttime levels of artificial, outdoor light exposure, stratified by quartile, were associated with an increased prevalence of hypnotic prescriptions and daily dose intake. Furthermore, older adults exposed to higher levels of artificial, outdoor light at night were more likely to use hypnotic drugs for longer periods or higher daily dosages. "This study observed a significant association between the intensity of outdoor, artificial, nighttime lighting and the prevalence of insomnia as indicated by hypnotic agent prescriptions for older adults in South Korea," said Kyoung-bok Min, PhD, an associate professor in the Department of Occupational and Environmental Medicine at Seoul National University College of Medicine in South Korea. "Our results are supportive data that outdoor, artificial, nighttime light could be linked to sleep deprivation among those while inside the house."

Cells decide when to divide based on their internal clocks -- ScienceDaily

Lead author of the study, Dr Bruno Martins from the University of Cambridge, said: "Cells born in the early part of the day grow to a smaller size before dividing again, because they seem to be in a 'rush' to divide before the end of the day. In contrast, cells born later in the day are in less of a 'rush', and therefore they grow to a bigger size, and avoid dividing in the period that normally corresponds to darkness at night." The team will next use their experimental results and the models developed to explain them to look at what molecules and genes are involved in this process and to explore its evolutionary function.

Body clock researchers prevent liver cancer growth in mice -- ScienceDaily

The body's clock, called the circadian clock, is an intrinsic, 24-hour timekeeping system that operates in all cells of the body and regulates sleep, metabolism and other vital body functions. "We were able to inhibit the growth of liver cancer in a mouse model by manipulating the circadian clock at the cellular level," said Kristin Eckel-Mahan, Ph.D., the study's senior author and an assistant professor with the Center for Metabolic and Degenerative Diseases at McGovern Medical School at UTHealth.

Mouse and human skin cells produce melanin on a 48-hour cycle -- ScienceDaily

. They observed that a 48-hour cycle of exposure resulted in the darkest coloration of the cells while minimizing the effects of stress, even when they controlled for total dosage of exposure. "The results were so surprising," says Levy. "We expected daily synchronization of the cell's protective cycles." Levy and her colleagues, including co-senior author and systems biologist Shai Shen-Orr and his PhD student Avelet Alpert of the Technion -- Israel Institute of Technology, observed that MITF (microphthalmia-associated transcription factor) seemed to play a role in synchronizing the protective cycles. MITF was previously shown to control production of melanin and its spread to surrounding skin cells. They found that upon one ultraviolet exposure, MITF expression fluctuates every 48 hours. Another exposure 24 hours later seemed to disrupt this expression pattern.

Antipsychotics ineffective for treating ICU delirium -- ScienceDaily

he large, multi-site MIND USA (Modifying the INcidence of Delirium) study sought to answer whether typical and atypical antipsychotics -- haloperidol or ziprasidone -- affected delirium, survival, length of stay or safety. "We found, after extensive investigation with medical centers all over the country, that the patients who get these potentially dangerous drugs are not experiencing any improvements whatsoever in delirium, coma, length of stay or survival," said senior author by E. Wesley Ely, MD, MPH, professor of Medicine at Vanderbilt University School of Medicine, associate director of Research for the VA Geriatric Research Education Clinical Center, and co-director of the CIBS (Critical Illness, Brain dysfunction, and Survivorship) Center at Vanderbilt University Medical Center. Researchers screened nearly 21,000 patients at 16 U.S. medical centers. Of the 1,183 patients on mechanical ventilation or in shock, 566 became delirious and were randomized into groups receiving either intravenous haloperidol, ziprasidone or placebo (saline). The investigators found no significant difference in duration of delirium or coma among participants on haloperidol or ziprasidone compared to placebo.

Man's Bipolar Mood Cycles Linked to the Moon | American Council on Science and Health

The author observed the behavior of a 51-year-old man with bipolar disorder. Patients with bipolar disorder experience manic-depressive cycles. The depressive cycles resemble those of patients suffering from severe depression, while during manic cycles, patients are hyperactive. Sleep patterns are abnormal, with patients sleeping too much during depressive episodes and not enough during manic episodes. In a sort of vicious cycle, disturbances in sleep pattern appear to be both a cause and effect of manic-depressive episodes.

How do muscles know what time it is? -- ScienceDaily

In collaboration with Italian and Austrian colleagues (from the Venetian Institute of Molecular Medicine and the Universities of Padua, Graz, and Trieste) the researchers identified certain processes that are switched on at night by the regulators of the internal clock: "They include, for example, fat storage, glucose metabolism and insulin sensitivity," explains Henriette Uhlenhaut. At the same time, opposing processes such as fatty acid oxidation and protein breakdown are throttled down, according the authors. These patterns are especially pronounced in the hours before awakening and are thought to prepare the muscles for the day ahead. In the final step, the scientists investigated possible ways to intervene in these processes. To this end, they examined mice lacking these master regulators. Without a circadian clock, the animals were leaner, with less fat and more muscle mass. "Taken together, our work has revealed an entire metabolic network at multiple levels," Uhlenhaut explains. "Another biologically exciting finding is that, contrary to expectations, the key regulator is not centrally located in the brain, but is in fact the internal clock of the muscle cells themselves." In the long term, the authors will investigate the mechanisms also in humans and try to find a way for therapeutic interventions. Their hope is that it might be possible to counteract insulin resistance in type 2 diabetes or to stimulate energy use to combat obesity.

A Smartphone App Reveals Erratic Diurnal Eating Patterns in Humans that Can Be Modulated for Health Benefits. - PubMed - NCBI

The daily intake duration (95% interval) exceeded 14.75 hr for half of the cohort. When overweight individuals with >14 hr eating duration ate for only 10-11 hr daily for 16 weeks assisted by a data visualization (raster plot of dietary intake pattern, "feedogram") that we developed, they reduced body weight, reported being energetic, and improved sleep. Benefits persisted for a year.