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Insomnia Is Bad For The Heart; Increases Blood Pressure

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Can't sleep at night? A new study published in the journal Sleep has found that people who suffer from insomnia have heightened nighttime blood pressure, which can lead to cardiac problems. The investigation, which measured the 24-hour blood pressure of insomniacs compared to sound sleepers, was conducted by researchers from the Université de Montréal, its affiliated Hôpital du Sacré-Cœur de Montréal Sleep Disorders Centre and the Université Laval."Over many years, chronic insomnia can have negative effects on the hearts of otherwise healthy individuals," says lead author Paola A. Lanfranchi, a professor in the Université de Montréal Faculty of Medicine and researcher at the Hôpital du Sacré-Cœur de Montréal Sleep Disorders Centre. "Whereas blood pressure decreases in regular sleepers and gives their heart a rest, insomnia provokes higher nighttime blood pressure that can cause long-term cardiovascular risks and damage the heart."

The findings are important given that insomnia, which is a chronic difficulty falling or staying asleep, affects up to 48 percent of the population at some point in their lives. As part of the study, the scientific team recruited 13 otherwise healthy chronic insomniacs and 13 good sleepers. Subjects spent 40 hours in the sleep laboratory: two nights for adaptation and one for monitoring followed by the intervening day.

"Blood pressure cycles are mainly linked to the sleep-wake cycle," says co-author Jacques Montplaisir, a professor in the Université de Montréal Department of Psychiatry and director of Hôpital du Sacré-Cœur de Montréal Disorders Center. "Since blood pressure is heightened among insomniacs, those with overt cardiac disease are particularly at risk for progression of the disease."

The article "Nighttime Blood Pressure in Normotensive Subjects With Chronic Insomnia: Implications for Cardiovascular Risk," published in Sleep was authored by Paola A. Lanfranchi, Marie-Hélène Pennestri, Lorraine Fradette, Marie Dumont and Jacques Montplaisir of the Université de Montréal and its affiliated Hôpital du Sacré-Cœur de Montréal, as well as Charles M. Morin of the Université Laval.

This study was funded by the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Québec and the Fonds de Recherche en Santé du Québec.

How To Boost Value Of Alzheimer's-fighting Compounds

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The polyphenols found in red wine are thought to help prevent Alzheimer's disease
The polyphenols found in red wine are thought to help prevent Alzheimer's disease, and new research from Purdue University and Mount Sinai School of Medicine has shown that some of those compounds in fact reach the brain.Mario Ferruzzi, a Purdue associate professor of food science; Connie Weaver, Purdue's head of foods and nutrition; and Elsa Janle, a Purdue associate professor of foods and nutrition, found that the amount of polyphenols from grapeseed extract that can reach a rat's brain is as much as 200 percent higher on the 10th consecutive day of feeding as compared to the first. Many previous experiments, in which absorption was measured after single or sporadic doses, often found very little, if any, of the bioactive polyphenols reaching brain tissues. However, more chronic exposure appears to improve absorption.

"This shows that reasonable and chronic consumption of these products may be the way to go, rather than single, high doses, similar to drugs," said Ferruzzi, who collaborated on the research with Mount Sinai's Dr. Giulio Pasinetti. "It's like eating an apple a day, not a case of apples over two days every month."

A paper detailing the findings was published in the early online version of the September issue of the Journal of Alzheimer's Disease.

Polyphenols, compounds found in the skins and seeds of grapes, are thought to prevent the formation of beta-amyloid protein, which creates the plaque in the brain that causes Alzheimer's disease. Alzheimer's is a progressive brain disease that destroys memory and cognitive skills and affects as many as 4.5 million Americans, according to the National Institute on Aging.

Pasinetti, the Aidekman Family Professor in Neurology and director of the Center of Excellence for Novel Approaches to Neurotherapeutics, said discovering how polyphenols are absorbed and distributed to the brain can impact researchers' understanding of the amount of grape products or red wine a person would need to consume to most effectively combat Alzheimer's disease.

"The most important thing is that when we follow the repetitive administration of this compound, we were able to observe the transfer of the compound to the brain," Pasinetti said. "This may help us figure out the proper concentration necessary to get these chemicals to the brain."

Ferruzzi said the study dealt with polyphenols, but also could be important for determining proper doses of other compounds or drugs for patients. Testing of a pharmaceutical, for example, could show that the drug is too potent when given repetitively; whereas that might not be apparent if the drug is administered on non-consecutive days or weeks.

"It could become important in terms of side effects," Ferruzzi said. "You could be overdosing because the body is adapting and absorbing or metabolizing these compounds differently over time."

Pasinetti is the principal investigator for the Center of Excellence for Research and Complementary and Alternative Medicine in Alzheimer's Disease grant from the National Institutes of Health that funded the work. Ferruzzi said further studies will focus on the mechanisms that control absorption of compounds during chronic consumption.

Vitamin C Deficiency Impairs Early Brain Development, Guinea Pig Study Finds

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Guinea pigs
New research at LIFE – Faculty of Life Sciences at University of Copenhagen shows that vitamin C deficiency may impair the mental development of new-born babies.In the latest issue of the well-known scientific journal The American Journal of Clinical Nutrition, a group of researchers headed by professor Jens Lykkesfeldt shows that guinea pigs subjected to moderate vitamin C deficiency have 30 per cent less hippocampal neurones and markedly worse spatial memory than guinea pigs given a normal diet. Like guinea pigs, human beings are dependent on getting vitamin C through their diet, and Jens Lykkesfeldt therefore speculate that vitamin C deficiency in pregnant and breast-feeding women may also lead to impaired development in foetuses and new-born babies.

The brain retains vitamin C

Several factors indicate that the neonatal brain, in contrast to other tissue, is particularly vulnerable to even a slight lowering of the vitamin C level. The highest concentration of vitamin C is found in the neurons of the brain and in case of a low intake of vitamin C, the remaining vitamin is retained in the brain to secure this organ. The vitamin thus seems to be quite important to brain activity. Tests have shown that mouse foetuses that were not able to transport vitamin C develop severe brain damage. Brain damage which resembles the ones found in premature babies and which are linked to learning and cognitive disabilities later in life.

Widespread vitamin C deficiency

In some areas in the world, vitamin C deficiency is very common – population studies in Brazil and Mexico have shown that 30 to 40 per cent of the pregnant women have too low levels of vitamin C, and the low level is also found in their foetuses and new-born babies. It is not yet known to what extent new-born babies in Denmark or the Western World suffer from vitamin C deficiency but a conservative estimate would be 5 to 10 per cent based on the occurrence among adults.

“We may thus be witnessing that children get learning disabilities because they have not gotten enough vitamin C in their early life. This is unbearable when it would be so easy to prevent this deficiency by giving a vitamin supplement to high-risk pregnant women and new mothers" says Jens Lykkesfeldt whose research group is currently studying how early in pregnancy vitamin C deficiency affects the embryonic development of guinea pigs and whether the damage may be reversed after birth.