 |
|
Animal study suggests inadequate sleep may exacerbate cellular aging in the elderly
June 30, 2008Cellular response to sleep deprivation is impaired in old mice
PHILADELPHIA - Researchers at the University of Pennsylvania School of Medicine have shown that the unfolded protein response, which is a reaction to stress induced by sleep deprivation, is impaired in the brains of old mice.
The findings suggest that inadequate sleep in the elderly, who normally experience sleep disturbances, could exacerbate an already-impaired protective response to protein misfolding that happens in aging cells. "Protein misfolding and aggregation is associated with many diseases like Alzheimer's and Parkinson's," notes first author Nirinjini Naidoo, PhD, Assistant Professor in the Division of Sleep Medicine. The study appears in the June issue of the Journal of Neuroscience.
The unfolded protein response (UPR) is one part of the quality control system for monitoring protein synthesis in the endoplasmic reticulum, the cellular compartment where some proteins are made. In this study, researchers found that the UPR was activated in 10-week old, sleep-deprived mice, so that misfolded proteins did not accumulate in the endoplasmic reticulum of brain cells in the cerebral cortex. However, in two-year-old, sleep-deprived mice, the UPR failed to do its job and misfolded proteins clogged the endoplasmic reticulum. Old mice that were not stressed by sleep deprivation were shown to already have an impaired UPR.
Sleep in mice is characterized by short periods of inactivity throughout the day and night. On average, mice sleep approximately one hour for every two they are awake. In order to deprive mice of sleep, researchers constantly monitored and gently stroked the mice with a brush to disturb periods of inactivity.
At 3, 6, 9, or 12 hours of sleep deprivation, proteins were examined from the mouse brains. By six hours of sleep deprivation, young mice demonstrated that the UPR system was in place because protein synthesis was shut off by a chaperone protein called BiP/GRP78. In contrast, there was no BiP/GRP78 in old mice so protein synthesis continued.
Old mice also had less of the proteins that refold abnormal proteins than young mice, and old mice had more of the proteins that cause cell death than young mice. Thus, several processes are upset in old mouse brains by sleep deprivation, and the overall result is a further accumulation of misfolded proteins.
"We could speculate that sleep disturbance in older humans places an additional burden on an already-stressed protein folding and degradation system," says Naidoo.
Future studies will examine whether augmenting key protective proteins delays the effects of aging and reduces sleep disturbances.
University of Pennsylvania School of Medicine
The unfolded protein response (UPR) is one part of the quality control system for monitoring protein synthesis in the endoplasmic reticulum, the cellular compartment where some proteins are made. In this study, researchers found that the UPR was activated in 10-week old, sleep-deprived mice, so that misfolded proteins did not accumulate in the endoplasmic reticulum of brain cells in the cerebral cortex. However, in two-year-old, sleep-deprived mice, the UPR failed to do its job and misfolded proteins clogged the endoplasmic reticulum. Old mice that were not stressed by sleep deprivation were shown to already have an impaired UPR.
Sleep in mice is characterized by short periods of inactivity throughout the day and night. On average, mice sleep approximately one hour for every two they are awake. In order to deprive mice of sleep, researchers constantly monitored and gently stroked the mice with a brush to disturb periods of inactivity.
At 3, 6, 9, or 12 hours of sleep deprivation, proteins were examined from the mouse brains. By six hours of sleep deprivation, young mice demonstrated that the UPR system was in place because protein synthesis was shut off by a chaperone protein called BiP/GRP78. In contrast, there was no BiP/GRP78 in old mice so protein synthesis continued.
Old mice also had less of the proteins that refold abnormal proteins than young mice, and old mice had more of the proteins that cause cell death than young mice. Thus, several processes are upset in old mouse brains by sleep deprivation, and the overall result is a further accumulation of misfolded proteins.
"We could speculate that sleep disturbance in older humans places an additional burden on an already-stressed protein folding and degradation system," says Naidoo.
Future studies will examine whether augmenting key protective proteins delays the effects of aging and reduces sleep disturbances.
University of Pennsylvania School of Medicine
Sleep Deprivation Current Events and Sleep Deprivation News RSSHigh levels of prenatal smoking exposure affect sleep patterns in preterm neonates
A study in the Dec. 1 issue of the journal Sleep is the first to show that high levels of prenatal smoking exposure strongly modify sleep patterns in preterm neonates, which places infants at a higher risk for developmental difficulties that could persist throughout early and middle childhood.
Association found between severe obstructive sleep apnea
A study in the October 15 issue of the Journal of Clinical Sleep Medicine shows that unrelated to obesity, people with severe SDBs consume a more unhealthy diet, which may be a factor contributing to greater cardiovascular morbidity and mortality. These findings were most evident among women.
Loss of sleep, even for a single night, increases inflammation in the body
Loss of sleep, even for a few short hours during the night, can prompt one's immune system to turn against healthy tissue and organs.
Mom's mood, baby's sleep: what's the connection?
If there's one thing that everyone knows about newborn babies, it's that they don't sleep through the night, and neither do their parents.
Exploring the function of sleep
Is sleep essential? Ask that question to a sleep-deprived new parent or a student who has just pulled an "all-nighter," and the answer will be a grouchy, "Of course!"
Kids with pets grow up to be snorers
A predisposition to adult snoring can be established very early in life. Research published today in BioMed Central's open access journal Respiratory Research describes possible childhood risk factors, including exposure to animals, early respiratory or ear infections and growing up in a large family.
1 sleepless night increases dopamine in the human brain
Just one night without sleep can increase the amount of the chemical dopamine in the human brain, according to new imaging research in the August 20 issue of The Journal of Neuroscience.
Less REM sleep associated with being overweight among children and teens
Children and teens who get less sleep, especially those who spend less time in rapid eye movement (REM) sleep, may be more likely to be overweight, according to a report in the August issue of Archives of General Psychiatry, one of the JAMA/Archives journals.
Searching for shut eye: Penn study identifies possible sleep gene
While scientists and physicians know what happens if you don't get six to eight hours of shut-eye a night, investigators have long been puzzled about what controls the actual need for sleep. Researchers at the University of Pennsylvania School of Medicine might have an answer, at least in fruit flies. In a recent study of fruit flies, they identified a gene that controls sleep.
Poor sleep linked to suicidal behavior among children and adolescents with depressive episodes
A research abstract that will be presented on Thursday at SLEEP 2008, the 22nd Annual Meeting of the Associated Professional Sleep Societies (APSS), finds a link between poor sleep and suicidal behavior among children and adolescents with depressive episodes.
More Sleep Deprivation Current Events and Sleep Deprivation News Articles
| Sleep Deprivation Chamber by Adam P. Kennedy, Adrienne Kennedy | |
 | Crib Sheets Are You Covered? New Parent Sleep Deprivation Solutions: Practical and Effective Expectant Parent Strategies by Elizabeth Gardner TO GET MORE SLEEP, YOU'VE GOT TO PLAN AHEAD! Sleep deprivation is undeniably the hardest part of parenting in baby's first months. According to the American Academy of Pediatrics, newborns feed 8 to12 times a day--that means 2 to 3-hour sleep intervals for mom and dad! Clearly, the traditional advice "sleep when baby sleeps" isn't enough. Crib Sheets takes you further, offering practical... |
 | Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem by Committee on Sleep Medicine and Research Clinical practice related to sleep problems and sleep disorders has been expanding rapidly in the last few years, but scientific research is not keeping pace. Sleep apnea, insomnia, and restless legs syndrome are three examples of very common disorders for which we have little biological information. This new book cuts across a variety of medical disciplines such as neurology, pulmonology,... |
 | Sleep Deprivation: Basic Science, Physiology and Behavior (Lung Biology in Health and Disease) Analyzing ground-breaking research, this reference highlights the impact of sleep deprivation on the well-being of the individual and society-presenting current theories on the function of sleep, the effects of sleep deprivation on patients with medical and psychiatric conditions, as well as providing interpretative and methodological results in comparative studies of sleep... |
 | Sleep Deprivation: ...the inner limits of the anxious mind by Daniel Keane Collected poems, written between 1997 and 2003, showing the multi-faceted nature of daily neurotic life. From pleasure to pain, depression to ecstasy, love to hatred, each piece effectively describes nearly every emotion, without trite and superficial verses. With a lack of pretentions and ego, this collection is straight-forward and to the point, with a unique perspective on the thought... |
 | Sleep Deprivation - A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References by ICON Health Publications In March 2001, the National Institutes of Health issued the following warning: "The number of Web sites offering health-related resources grows every day. Many sites provide valuable information, while others may have information that is unreliable or misleading." Furthermore, because of the rapid increase in Internet-based information, many hours can be wasted searching, selecting, and... |
 | Dead on Their Feet: Teen Sleep Deprivation and Its Consequences (Science of Health) by Joan Esherick Do you ever feel exhausted and drowsy, like you need more sleep? If you do, you're not alone. A recent study by the National Sleep Foundation (NSF) found that 60 percent of people under the age of eighteen complained of daytime tiredness. Fifteen percent (one out of every seven) said they were so tired they fell asleep in school. You may think that not getting sufficient sleep is no big deal, but... |
| How healthy are the new 80-hour workweek limits for residents? Sleep deprivation still widespread.(Practice Trends): An article from: Clinical Psychiatry News by Bruce Jancin This digital document is an article from Clinical Psychiatry News, published by International Medical News Group on August 1, 2003. The length of the article is 519 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web... | |
 | Seven Days to a Perfect Night's Sleep by Debra L. Gordon Are You Desperately Seeking Sleep?The answer is yes for 3 out of 10 people who can’t fall asleep, stay asleep, or wake up feeling refreshed. As a result, you go through the day in a fog, dozing off at work, behind the wheel, or at school. In other words, never where—or when—you should be. It’s time to open your eyes to a healthy solution. And all it takes is seven days! With Sleep-Smart... |
 | Good Nights: How to Stop Sleep Deprivation, Overcome Insomnia, and Get the Sleep You Need by Gary K. Zammit, Jane A. Zanca St. Lukes-Roosevelt Hospital, New York City, NY. Addresses the need for quality sleep and what may be causing sleep deprivation. For consumers. Covers: sleep cycles, tips, behavioral treatments, sleeping pills, sleep rhythms, children and adolescents, sleep disorders, and consulting a sleep specialist. Hardcover edition was published in 1997.... |
| © 2009 BrightSurf.com |