Category: Dementia

A brain network which links dementia and schizophrenia has been discovered.

A specific brain network which is vulnerable to dementia and schizophrenia has been newly identified.

The study, which is published in the journal Proceedings of the National Academy of Sciences, focused on the structure of the brain’s grey matter, the nerve cells which store and process information (Douaud et al., 2014).

The neuroscientists found that a wide-ranging network in the brain developed late in adolescence and also started to degenerate early with aging.

Dr. Gwenaëlle Douaud, the study’s first author, explained:


”Our results show that the same specific parts of the brain not only develop more slowly, but also degenerate faster than other parts.

These complex regions, which combine information coming from various senses, seem to be more vulnerable than the rest of the brain to both schizophrenia and Alzheimer’s, even though these two diseases have different origins and appear at very different, almost opposite, times of life.”

To reach these conclusions, researchers scanned the brains of 484 people who were between 8 and 85-years-old.

They wanted to see how the brain’s structure naturally changes with age.

What they saw was that there is a network of regions in the brain which tend to develop together and which also degenerate together in later life.

The network reaches through many important parts of the brain, connecting areas involved in higher-order thinking.

The findings fit with a theory first put forward in the 1880s about how dementia develops.

The ‘retrogenesis’ theory states that in Alzheimer’s disease, the brain degenerates in the reverse order to how it originally developed.

In the early stages of dementia, a person’s mental faculties can regress to around those of an 11-year-old, then, over the next four or five years, regresses still further back to the level of a 4- or 5-year-old.

Professor Hugh Perry, of the Medical Research Council, said:

“Early doctors called schizophrenia ‘premature dementia’ but until now we had no clear evidence that the same parts of the brain might be associated with two such different diseases.

This large-scale and detailed study provides an important, and previously missing, link between development, ageing and disease processes in the brain.

It raises important issues about possible genetic and environmental factors that may occur in early life and then have lifelong consequences.

The more we can find out about these very difficult disorders, the closer we will come to helping sufferers and their families.”

Image credit: US Air Force

Brain aging and dementia dramatically slowed by special diet, new study finds.

Neuroscientists have shown that a calorie-restricted diet almost stops gene expressions related to aging and dementia.

Dr. Stephen D. Ginsberg, who presented the new study’s results at the Society for Neuroscience annual meeting, said:

“Our study shows how calorie restriction practically arrests gene expression levels involved in the aging phenotype — how some genes determine the behavior of mice, people, and other mammals as they get old.”

Mice in the study were fed 30% fewer calories, which likely reduced some of the aspects of aging which can lead to diseases like Alzheimer’s.

The life-preserving effect of calorie restriction in animals has been known for some time, but the same effect is not proven in humans.

This study is the first to examine how a calorie restricted diet affects the expression of over 10,000 genes.

Female mice were chosen for this study because, like female humans, they are more susceptible to dementia than males.

The effect of the restricted diet was tested by examining the hippocampal region of the brain, which is one of the first to be affected by Alzheimer’s.

The hippocampus is central to learning and memory, and damage to this area with aging is one of the main causes of the symptoms of Alzheimer’s disease.

The results showed that the calorie restricted diet almost stopped the natural rise and fall of almost 900 different genes related to memory and aging.

Exactly how this huge range of changes provides a protective effect against the effects of aging is not yet known.

While the results do not point to a “fountain of youth,” Dr. Ginsberg said it does:

“…add evidence for the role of diet in delaying the effects of aging and age-related disease.”

• Read on: 10 Ways to Prevent Alzheimer’s Disease

Study finds diet that gives brain fuel to repair age-related damage.

A high-fat diet can postpone brain aging in mice, a new study has found, but the results may also help fight Alzheimer’s and Parkinson’s.

Researchers have discovered that a high-fat diet — from fatty acids contained in coconut oil, or similar — gives brain cells extra fuel to burn, which helps its repair mechanism work more efficiently.

The Danish-led research targeted Cockayne syndrome, a rare genetic condition which causes a defect in the cell repair mechanisms (Scheibye-Knudsen et al., 2014).

Children with the syndrome age prematurely and often die at just 10 to 12-years-old.

Professor Vilhelm Bohr, who led the study, said:

“The study is good news for children with Cockayne syndrome, because we do not currently have an effective treatment.

Our study suggests that a high-fat diet can postpone aging processes.

A diet high in fat also seems to postpone the aging of the brain.

The findings therefore potentially imply that patients with Alzheimer’s and Parkinson’s disease in the long term may benefit from the new knowledge.”

The findings may be beneficial to everyone since, with age, we all develop brain defects which lead to a reduction in mental capacity, as well as the increasing risk of Alzheimer’s and Parkinson’s.

In this study, mice with the defect in the DNA repair system were fed on a high-fat diet containing medium-chain fatty acids.

This diet postponed typical age-related problems like hearing loss and difficulties maintaining a healthy weight.

Dr. Morten Scheibye-Knudsen, the study’s first author, said:

“In cells from children with Cockayne syndrome, we have previously demonstrated that aging is a result of the cell repair mechanism being constantly active.

It eats into the resources and causes the cell to age very quickly.

We therefore hope that a diet with a high content of coconut oil or similar fats will have a beneficial effect, because the brain cells are given extra fuel and thus the strength to repair the damage.”

Image credit: Liz Jones

Previously ‘untreatable’ dementias could be managed with lifestyle changes.

Some types of dementia are actually a result of many tiny, unnoticed strokes damaging the brain over time, researchers at the Krembil Neuroscience Centre in Toronto, Canada, have found.

This suggests that this type of dementia could be treatable — probably through lifestyle changes.

The findings come from a study of five individuals who had their brains scanned over 16 consecutive weeks (Conklin et al., 2014).

The relatively frequent brain scans revealed that tiny spots were appearing on the MRI, which are characteristic of small strokes.

The appearance of the spots had not been noticed before because previous studies have scanned the brain at longer intervals — typically every year.

The spots did not produce any symptoms but, over time, it is thought the lesions can form into areas of white matter disease that are characteristic of dementia.

Around 50% of older individuals have this kind of white matter disease in their brains, although for many it is harmless.

For some patients, however, the disease can progress until the symptoms become severe.

Dr. Daniel Mandell, who led the study, said:

“We were surprised.

The findings suggest that the tiny, silent strokes are likely much more common than physicians previously appreciated, and these strokes are likely a cause of the age-related white matter disease that can lead to dementia.”

While there are no treatments for degenerative dementias, as this is vascular it may be possible to stop, or at least slow down, the process.

Dr. Frank Silver, Director of the Krembil Neuroscience Centre and one of the study’s authors, said:

“We don’t yet know whether these small strokes are responsible only some or most of the white matter disease seen in older patients.

But in those where it is the cause, the detection of white matter disease on brain imaging should trigger physicians to treat patients aggressively when managing stroke risk factors such as high blood pressure, diabetes, high cholesterol, cigarette smoking and lack of exercise not only to prevent further strokes, but also to reduce the development of cognitive impairment over time.”