British researchers have found that a run of poor sleep can have a dramatic effect on the internal workings of the human body.
The activity of hundreds of genes was altered when people’s sleep was cut to less than six hours a day for a week.
Writing in the journal Proceedings of the National Academy of Sciences, the researchers said the results helped explain how poor sleep damaged health.
Heart disease, diabetes, obesity and poor brain function have all been linked to substandard sleep.
What missing hours in bed actually does to alter health, however, is unknown.
So researchers at the University of Surrey analyzed the blood of 26 people after they had had plenty of sleep, up to 10 hours each night for a week, and compared the results with samples after a week of fewer than six hours a night.
More than 700 genes were altered by the shift. Each contains the instructions for building a protein, so those that became more active produced more proteins – changing the chemistry of the body.
Meanwhile the natural body clock was disturbed – some genes naturally wax and wane in activity through the day, but this effect was dulled by sleep deprivation.
Prof. Colin Smith, from the University of Surrey, said: “There was quite a dramatic change in activity in many different kinds of genes.”
Areas such as the immune system and how the body responds to damage and stress were affected.
British researchers have found that a run of poor sleep can have a dramatic effect on the internal workings of the human body
Prof. Colin Smith added: “Clearly sleep is critical to rebuilding the body and maintaining a functional state, all kinds of damage appear to occur – hinting at what may lead to ill health.
“If we can’t actually replenish and replace new cells, then that’s going to lead to degenerative diseases.”
He said many people may be even more sleep deprived in their daily lives than those in the study – suggesting these changes may be common.
Dr Akhilesh Reddy, a specialist in the body clock at the University of Cambridge, said the study was “interesting”.
He said the key findings were the effects on inflammation and the immune system as it was possible to see a link between those effects and health problems such as diabetes.
The findings also tie into research attempting to do away with sleep, such as by finding a drug that could eliminate the effects of sleep deprivation.
Dr. Akhilesh Reddy said: “We don’t know what the switch is that causes all these changes, but theoretically if you could switch it on or off, you might be able to get away without sleep.
“But my feeling is that sleep is fundamentally important to regenerating all cells.”
British researchers have raised the tantalizing prospect of treating a range of brain diseases, such as Alzheimer’s and Parkinson’s, all with the same drug.
In a study, published in Nature, researchers prevented brain cells dying in mice with prion disease.
It is hoped the same method for preventing brain cell death could apply in other diseases.
The findings are at an early stage, but have been heralded as “fascinating”.
Many neuro-degenerative diseases result in the build-up of proteins which are not put together correctly – known as misfolded proteins. This happens in Alzheimer’s, Parkinson’s and Huntington’s as well as in prion diseases, such as the human form of mad cow disease.
Researchers at the University of Leicester uncovered how the build-up of proteins in mice with prion disease resulted in brain cells dying.
They showed that as misfolded protein levels rise in the brain, cells respond by trying to shut down the production of all new proteins.
Researchers at the University of Leicester uncovered how the build-up of proteins in mice with prion disease resulted in brain cells dying
It is the same trick cells use when infected with a virus. Stopping production of proteins stops the virus spreading. However, shutting down the factory for a long period of time ends up killing the brain cells as they do not produce the proteins they actually need to function.
The team at the Medical Research Council laboratory in Leicester then tried to manipulate the switch which turned the protein factory off. When they prevented cells from shutting down, they prevented the brain dying. The mice then lived significantly longer.
Each neuro-degenerative disease results in a unique set of misfolded proteins being produced, which are then thought to lead to brain cells dying.
Prof. Giovanna Mallucci said: “The novelty here is we’re just targeting the protein shut-down, we’re ignoring the prion protein and that’s what makes it potentially relevant across the board.”
The idea, which has not yet been tested, is that if preventing the shut down protects the brain in prion disease – it might work in all diseases that have misfolded proteins.
Prof. Givanna Mallucci added: “What it gives you is an appealing concept that one pathway and therefore one treatment could have benefits across a range of disorders.
“But the idea is in its early stages. We would really need to confirm this concept in other diseases.”
The study has been broadly welcomed by other scientists although many point out that the research is in its infancy.
Fasting two days a week could prevent your brain shrinking with age, suggests new research.
Fasting was a common medical treatment in the past, but now new research suggests there may be good reason for it to make a comeback. This is because it seems to trigger all sorts of healthy hormonal and metabolic changes.
Researchers have long known that cutting back animals’ calories over an extended period can make them live up to 50% longer – it’s been harder to prove benefits in humans because few people can stick to this restrictive regimen.
But there’s now emerging evidence to show occasional fasting – which is much more manageable – also carries benefits. Fasting days involve eating between 500 and 800 calories (the usual daily intake for a woman is 2,000 calories, for a man, 2,500).
This intake appears to cause a drop in levels of growth-factor, a hormone linked with cancer and diabetes, as well as a reduction in “bad” LDL cholesterol and triglycerides (fats) in the blood.
Meanwhile, free radicals – the damaging molecules linked to disease – are dampened down. Studies also suggest that levels of inflammation can fall. And now there is the suggestion that fasting protects the brain, too.
“Suddenly dropping your food intake dramatically – cutting it by at least half for a day or so – triggers protective processes in the brain,” explains Professor Mark Mattson, head of neuroscience at the U.S. National Institute On Ageing.
“It is similar to the beneficial effect you get from exercise.”
This could help protect the brain against degenerative diseases such as Alzheimer’s and Parkinson’s.
Prof. Mark Mattson is one of the pioneers of research into fasting – a few years ago he made a breakthrough when he found rats could get nearly all the benefits of calorie restriction if the scientists only cut back their calories every other day. On the next day the rats could eat as much as they liked and yet they showed the same benefits as rats on a low-calorie regimen all the time.
Suddenly it looked as if humans could benefit from a form of calorie restriction regimen that, unlike daily restriction, is feasible to follow. Now results of other trials are revealing the benefits.
In one study, reported last year in the International Journal of Obesity, a group of obese and overweight women was put on a diet of 1,500 calories a day while another group was put on a very low 500-calorie diet for two days, then 2,000 calories a day for the rest of the week.
Both groups were eating a healthy Mediterranean-style diet.
“We found that both lost about the same amount of weight and both saw a similar drop in biomarkers that increase your risk of cancer,” says Dr. Michelle Harvie, a dietitian at Manchester University who led the research.
“The aim was to find which was the most effective and we found that the women in the fasting group actually had a bigger improvement in sensitivity to insulin.” Improved insulin sensitivity means better control of blood sugar levels.
Fasting two days a week could prevent your brain shrinking with age, suggests new research
Last year researchers at Newcastle University reported that they had reversed diabetes in a small number of overweight people by putting them on an 800-calorie diet for eight weeks.
It’s possible that eating small amounts of calories every other day, as Dr. Michelle Harvie’s study allowed, is not only more bearable, but may be particularly effective at getting diabetics’ blood sugar under control.
Now, Prof. Mark Mattson has been investigating the benefits of various fasting regimens on the health of our brain cells.
According to an article that will be appearing in the leading science journal Nature Neuroscience next month, calorie restriction can protect the cells from damage and make them more resistant to stress.
“Part of this effect is due to what cutting calories does to appetite hormones such as ghrelin and leptin,” Prof. Mark Mattson explains.
“When you are not overweight, these hormones encourage growth of new brain cells, especially in the hippocampus.”
This is the area of the brain which is involved in laying down memories. If you start putting on weight, levels of ghrelin drop and brain cell replacement slows.
“The effect is particularly damaging in your 40’s and 50’s, for reasons that aren’t clear yet,” he says.
“Obesity at that age is a marker for cognitive problems later.”
The good news is that this brain-cell damage can be reversed by the two-day fasting regime, although so far Prof. Mark Mattson has shown this only in rats. A human trial is starting soon. There is reason to think it should work. Fasting every other day had a striking effect on people with asthma in a small study he ran a few years ago.
“After eight weeks they had lost eight per cent of their body weight, but they also benefited from the ability of calorie restriction to reduce inflammation. Tests showed that levels of inflammation markers had dropped by 90%.”
“As levels came down, their breathing became much easier,” says Prof. Mark Mattson.
However, Prof. MarK Mattson cautions that patients have to stick to the diet, as symptoms began to return two weeks after giving it up.
Not everyone will find fasting intermittently is something they can manage.
In Dr. Michelle Harvie’s recent study of overweight women, more patients in the continuous dieting group (who had to stick to 1,500 calories a day) wanted to continue with it than those on the two-day fasting regimen.
“It’s going to suit some people more than others,” Dr. Michelle Harvie says.
“For some, being able to cut out 3,000-4,000 calories in two days and then eat normally for the rest of the time is much more attractive than cutting back a little every day; for others it’s too drastic. It gives us another option. My experience is men seem to adapt better to it than women.”
But Prof. Mark Mattson believes these new fasting regimes could help tackle our failure to live more healthily.
“This research shows that successful brain ageing is possible for most individuals if they maintain healthy diets and lifestyles throughout their adult life,” he says.
The trouble is that our diets are too high in calories and we don’t do enough exercise, which is why, he says, brain diseases such as Alzheimer’s are on the rise.
So is there any harm in trying a little intermittent fasting ourselves? As a result of his research, Prof. Mark Mattson now keeps his own calorie intake down.
“I aim for about 1,800 calories a day, nothing drastic,” he says.
“During the week I don’t have any breakfast or lunch but I have a good evening meal. I know it’s not what most dietitians would recommend but it works very well for me.”
