Category: Dementia

New test for disease which affects 115 million people around the world.

A set of 10 blood proteins which reliably predict the onset of Alzheimer’s has been identified by a new study.

It could lead to a relatively cheap and non-invasive test for the disease within a few years.

At the moment the early stages of Alzheimer’s can be difficult to tell apart from the normal ageing process, until it is too late.

Only around 10% of older people with mild cognitive impairment go on to develop dementia within a year.

One of the study’s authors, Professor Simon Lovestone, explained:

“Alzheimer’s begins to affect the brain many years before patients are diagnosed with the disease.

Many of our drug trials fail because by the time patients are given the drugs, the brain has already been too severely affected.

A simple blood test could help us identify patients at a much earlier stage to take part in new trials and hopefully develop treatments which could prevent the progression of the disease.”

The new test, which could be available within two years, can predict the onset of Alzheimer’s in the next year with 87% accuracy.

This would enable drugs to be prescribed earlier and likely improve outcomes.

Finding the right proteins

The study used blood samples from 1,148 people (Hye et al., 2014).

Some had Alzheimer’s, others a mild cognitive impairment and some were elderly controls without dementia.

By analysing the blood samples, they found 10 proteins that could predict the progression from mild cognitive impairment to Alzheimer’s.

The study’s lead author, Dr Abdul Hye, said:

“Memory problems are very common, but the challenge is identifying who is likely to develop dementia.

There are thousands of proteins in the blood, and this study is the culmination of many years’ work identifying which ones are clinically relevant.

We now have a set of 10 proteins that can predict whether someone with early symptoms of memory loss, or mild cognitive impairment, will develop Alzheimer’s disease within a year, with a high level of accuracy.”

Previous studies have found that PET scans and lumbar punctures can predict the onset of dementia, but the former is very expensive and the latter invasive.

A blood test would provide a more cost-effective and less invasive test for a disease which is thought to affect 115 million people around the world.

Image credit: Bev Sykes

Even if you are already in middle age or later, the study has some good news.

Young adults who are in good physical shape performed better in cognitive tests 25 years later, a new study finds.

The study, published in the journal Neurology, also found that even if you didn’t get too much exercise in your youth, it’s never too late to start, as the benefits can still be seen later on.

One of the study’s authors, David R. Jacobs, said:

“Many studies show the benefits to the brain of good heart health.

“This is one more important study that should remind young adults of the brain health benefits of cardio fitness activities such as running, swimming, biking or cardio fitness classes.”

In the study, 2,747 people, whose average age was 25, did a treadmill test which measured their cardiorespiratory fitness (Zhu et al., 2014).

This involved them running on the treadmill while the speed and incline increased, until they had to stop.

Twenty-five years later they were given tests of decision-making, verbal memory and the relationship between their thinking skills and physical actions.

The results showed that for each extra minute they could stay on the treadmill at around 25-years-old, when they reached between 43 to 54-years-of-age, they could:

• recall 0.12 more words on a memory test,
• replace 0.92 more numbers with symbols in a psychomotor test.

Although these numbers might not seem striking, Jacobs said:

“These changes were significant, and while they may be modest, they were larger than the effect from one year of aging.

Other studies in older individuals have shown that these tests are among the strongest predictors of developing dementia in the future.

One study showed that every additional word remembered on the memory test was associated with an 18-percent decrease in the risk of developing dementia after 10 years.”

Even if you are already in middle age or later, the study has some good news.

Those who had managed to boost their fitness levels over the 25 years also enjoyed increased cognitive performance.

Image credit: Tom Wigley

Mice with the KLOTHO gene variant lived longer and were smarter.

Scientists have shown for the first time that people who have a variant of a gene called KLOTHO also have improved cognitive abilities, including better memories and enhanced thinking skills.

In parallel research on mice, the researchers found that when they increased the levels of the gene variant, the mice got smarter, perhaps due to increased connections between nerve cells (Dubal et al., 2014).

This could provide a promising avenue of research for tackling Alzheimer’s disease.

The study’s lead author, Dena Dubal said:

“This could be a major step toward helping millions around the world who are suffering from Alzheimer’s disease and other dementias.

If we could boost the brain’s ability to function, we may be able to counter dementias.”

In the human arm of the research, the scientists gave a whole battery of cognitive tests to over 700 people with and without the gene variant.

About 20-25% of participants had one copy of the gene variant, known as ‘KL-VS’,

Those with one copy, compared to none, performed better on the cognitive tests, regardless of their age, sex or genetic risk factors for Alzheimer’s disease.

Another of the study’s authors, Roderick Corriveau, said:

“These surprising results pave a promising new avenue of research

Although preliminary, they suggest that a form of klotho could be used to enhance cognition for people suffering from dementia.”

Like the humans in the study, the mice also performed better on cognitive tests, including those of memory and learning.

Lennart Mucke, the director of the Gladstone Institute of Neurological Disease, said:

“Overall our results suggest that KLOTHO may increase cognitive reserve or the brain’s capacity to perform everyday intellectual tasks.”

The gene takes its name from the entity in Greek mythology called ‘Clotho’, who was one of the ‘fates’ who were supposed to control the thread of people’s lives.

If this research bears further fruit, the KLOTHO gene could change the fate of many people’s lives.

Image credit: Micah Baldwin

“Some people wander aimlessly through life, but I am not one of them.”

Feeling useful and having a sense of purpose in life are clearly beneficial psychologically, but now research is revealing that there also physical benefits.

No matter what your age, new research finds, having a sense of purpose helps you live longer.

However, the earlier you find a sense of direction and purpose, the better.

The findings come from a study of more than 6,000 people who were followed over 14 years (Hill & Turiano, 2014).

The results showed that people who strongly agreed with statements like the following were less likely to die over the course of the study:

“Some people wander aimlessly through life, but I am not one of them.”

The researchers were surprised that these findings held, even for younger people.

Lead researcher, Patrick Hill, said:

“There are a lot of reasons to believe that being purposeful might help protect older adults more so than younger ones.

For instance, adults might need a sense of direction more, after they have left the workplace and lost that source for organizing their daily events.

In addition, older adults are more likely to face mortality risks than younger adults.

These findings suggest that there’s something unique about finding a purpose that seems to be leading to greater longevity.”

These findings are not isolated.

Recent studies have pointed to both the physical and psychological benefits of finding meaning in life, especially with advancing years:

• A 2009 study of 1,238 elderly people found that those with a sense of purpose lived longer.
• A 2010 study of 900 older adults found that those with a greater sense of purpose were much less likely to develop Alzheimer’s disease.
• Survey data often links a sense of purpose in life with increased happiness.

No matter what your age, then, it’s worth thinking about what gives your life meaning.

It doesn’t necessarily mean you have to have the whole thing planned out, but a sense of direction is clearly beneficial both psychologically and physically.

Find out what kinds of things people say give their lives meaning. Here’s an exercise for increasing meaningfulness and a study finding that feeling you belong increases the sense of meaning.

Image credit: godserv

Experimental chemical restores some lost brain cell function in schizophrenia.

An anticancer compound has reversed the behaviours associated with schizophrenia in mice.

On top of reversing these behaviours, the chemical also restores some lost brain cell function, the Johns Hopkins University School of Medicine research finds (Hayashi-Takagi et al., 2014).

The compound is a type of PAK inhibitor which has been tested in the treatment of cancer, Fragile X syndrome (a type of mental retardation) and Alzheimer’s disease.

Synaptic pruning

The drug works by targeting a natural process called ‘synaptic pruning’.

Synaptic pruning is one of the underlying biological processes thought to be important in the development of schizophrenia.

In adolescence it is normal for children’s brain to undergo quite extensive synaptic pruning: a process where the brain’s grey matter is lost over time.

The refining of the brain’s synapses seems to be beneficial to boosting cognitive control.

In schizophrenia, however, the pruning process gets out of control and many connections which are needed by the brain are destroyed.

The study’s leader Akira Sawa, explained the results:

“By using this compound to block excess pruning in adolescent mice, we also normalized the behavior deficit.

That we could intervene in adolescence and still make a difference in restoring brain function in these mice is intriguing.”

This is just one of many approaches being tried to tackle schizophrenia, which is a fiendishly complicated condition.

Although there is not yet evidence that the PAK inhibitor will work in humans, Sawa, the director of the Johns Hopkins Schizophrenia Center, says:

“Drugs aimed at treating a disease should be able to reverse an already existing defect as well as block future damage.

This compound has the potential to do both.”

Image credit: Birth Into Being

Two pivotal processes affected by copper may hasten the onset and progression of Alzheimer’s.

Copper may be one of the main environmental factors in Alzheimer’s disease, according to recent research which has identified how the metal stops the brain clearing a toxic protein.

The conclusion comes from a study of both mouse and human brain cells and is published in the journal Proceedings of the National Academy of Sciences (Singh et al., 2013).

Dr Rashid Deane of the University of Rochester Medical Center, and one of the study’s lead authors explains:

“It is clear that, over time, copper’s cumulative effect is to impair the systems by which amyloid beta [a toxic protein] is removed from the brain.

This impairment is one of the key factors that cause the protein to accumulate in the brain and form the plaques that are the hallmark of Alzheimer’s disease.”

Amyloid beta is a toxic byproduct of cellular activity which is crucial in the development of the plaques found in the brains of those with Alzheimer’s disease.

The recent study put very low levels of copper into the drinking water of mice over three months, then examined how this affected their brains.

They found that the copper accumulated in the vessels which feed blood to the brain.

The copper then disrupted the removal of amyloid beta from the brain cells.

Researchers confirmed this process in both mouse and human brain cells.

Copper penetrates the brain

In a second phase of the research, they looked at how copper affected the mice’s brain cells over time.

What they found was that with age the blood-brain barrier became ‘leaky’ so that copper could penetrate the brain.

There it tended to increase the production of amyloid beta.

Together, then, these two processes show that copper can both inhibit the clearance of amyloid beta and stimulate production in the brain.

Balanced consumption

Since copper is a ubiquitous essential metal that is vital to many bodily functions, it’s not simply a case of cutting it out of the diet.

Deane explains:

“Copper is an essential metal and it is clear that these effects are due to exposure over a long period of time. The key will be striking the right balance between too little and too much copper consumption. Right now we cannot say what the right level will be, but diet may ultimately play an important role in regulating this process.”

Image credit: ML Cohen

Henry Molaison’s brain has been preserved forever as a Google Map.

Henry Molaison has–or rather had–the most famous amnesiac brain in psychology.

The results of tests carried out on him over the last five decades have produced thousands of academic papers examining all aspects of memory and thinking.

Molaison’s story is tragic: he agreed to experimental surgery in 1953 in an attempt to be free of very severe epilepsy which had blighted his life from an early age.

The surgery–which cut out most of his hippocampi–was successful in controlling his epilepsy, but had the unintended consequence of leaving him severely amnesic.

After the surgery he lost the ability to lay down new memories, as well as losing many memories from around 1 to 2 years before the surgery was performed.

Here is conversation he had with Suzanne Corkin, a psychologist he had been working with–and seen regularly–for thirty years:

“Have we ever met before?” [Corkin asked]

“Yes, I think we have”

“Where?”

“Well, in high school?”

“Yes.”

“What school?”

“In East Hartford.”

“Have we ever met any place besides high school?”

Henry paused. “Tell you the truth, I can’t–no. I don’t think so” (from: Permanent Present Tense by Suzanne Corkin)

In fact, they didn’t meet in high school but when Corkin was a grad student. The other things Molaison ‘remembered’ were really his own pre-surgery memories. He himself had attended high school in East Hartford, Connecticut.

By carrying out experiments on Molaison’s memory, psychologists made all kinds of breakthroughs, here are a couple:

• He  was able to learn new skills despite not remembering he had learnt them. This suggests a separation in the brain between procedural and semantic memory.
• He could learn unconsciously when patterns were hidden in tests. This suggested that it was only certain types of new learning which he couldn’t achieve.

Molaison died in 2008 and one year later neuroscientists spent 53 hours dissecting his brain, also taking a series of detailed digital images.

These images have now been reconstructed to create a 3-D microscopic model of his brain, which exists as a Google map.

The leader of the team, Dr. Jacopo Annese, explained:

“Our goal was to create this 3-D model so we could revisit, by virtual dissection, the original surgical procedure and support retrospective studies by providing clear anatomical verification of the original brain lesion and the pathological state of the surrounding areas of H.M.’s brain.”

Even after his death Henry Molaison continues to provide insights into how memory works; Dr Annese continues:

“For many decades, it was thought the main area of damage responsible for H.M.’s amnesia was the hippocampus. However, these new findings show that a substantial portion of H.M.’s hippocampus may have been spared by the operation. Instead, H.M.’s entorhinal cortex […] was almost completely destroyed.

This new discovery suggests that the entorhinal cortex may be more important for H.M.’s memory deficits than previously thought. Indeed, this is the same region that seems to be most heavily impacted during the earliest stages of Alzheimer’s disease.”

Henry Molaison lives on in introductory psychology courses across the world where the results of the studies carried out on him are taught to new generations of psychology students every year.

He also lives on in the form of a highly detailed Google Map of his brain.

Image credit: https://thedigitalbrainlibrary.org/