Saturday December 14, 2019

Superagers’ Brains Offer Clues for Sharp Memory in old age

The work is the flip side of the disappointing hunt for new drugs to fight or prevent Alzheimer's disease

0
//
Superagers
Neuroscientist Emily Rogalski poses for a photo in at the Northwestern University Feinberg School of Medicine in Chicago on Feb. 16, 2018. Rogalski is leading a study of "superagers," people in their 80s and 90s who have retained unusually sharp memory, in the hope of finding ways to protect others from memory loss. VOA

It’s pretty extraordinary for people in their 80s and 90s to keep the same sharp memory as someone several decades younger, and now scientists are peeking into the brains of these “superagers” to uncover their secret.

The work is the flip side of the disappointing hunt for new drugs to fight or prevent Alzheimer’s disease.

Instead, “why don’t we figure out what it is we might need to do to maximize our memory?” said neuroscientist Emily Rogalski, who leads the SuperAging study at Chicago’s Northwestern University.

ALSO READ: Second Innings: Deep Probeen Porisheba (DPP) Creates new Milestone in Taking care of Greying Population in Kolkata

Parts of the brain shrink with age, one of the reasons why most people experience a gradual slowing of at least some types of memory late in life, even if they avoid diseases like Alzheimer’s.

superagers
These elite elders are “more than just an oddity or a rarity,” said neuroscientist Molly Wagster of the National Institute on Aging, which helps fund the research. Pixabay

But it turns out that superagers’ brains aren’t shrinking nearly as fast as their peers’. And autopsies of the first superagers to die during the study show they harbor a lot more of a special kind of nerve cell in a deep brain region that’s important for attention, Rogalski told a recent meeting of the American Association for the Advancement of Science.

These elite elders are “more than just an oddity or a rarity,” said neuroscientist Molly Wagster of the National Institute on Aging, which helps fund the research. “There’s the potential for learning an enormous amount and applying it to the rest of us, and even to those who may be on a trajectory for some type of neurodegenerative disease.”

What does it take to be a superager? A youthful brain in the body of someone 80 or older. Rogalski’s team has given a battery of tests to more than 1,000 people who thought they’d qualify, and only about 5 percent pass. The key memory challenge: Listen to 15 unrelated words, and a half-hour later recalls at least nine. That’s the norm for 50-year-olds, but the average 80-year-old recalls five. Some superagers remember them all.

“It doesn’t mean you’re any smarter,” stressed superager William “Bill” Gurolnick, who turns 87 next month and joined the study two years ago.

Nor can he credit protective genes: Gurolnick’s father developed Alzheimer’s in his 50s. He thinks his own stellar memory is bolstered by keeping busy. He bikes and plays tennis and water volleyball. He stays social through regular lunches and meetings with a men’s group he co-founded.

“Absolutely that’s a critical factor in keeping your wits about you,” exclaimed Gurolnick, fresh off his monthly gin game.

Rogalski’s superagers tend to be extroverts and report strong social networks, but otherwise, they come from all walks of life, making it hard to find a common trait for brain health. Some went to college, some didn’t. Some have high IQs, some are average. She’s studied people who’ve experienced enormous trauma, including a Holocaust survivor; fitness buffs and smokers; teetotalers and those who tout a nightly martini.

superagers
The superagers had four to five times more of these neurons than the typical octogenarian, Rogalski said – more even than the average young adult. Pixabay

But deep in their brains is where she’s finding compelling hints that somehow, superagers are more resilient against the ravages of time.

Early on, brain scans showed that a superager’s cortex – an outer brain layer critical for memory and other key functions – is much thicker than normal for their age. It looks more like the cortex of healthy 50- and 60-year-olds.

It’s not clear if they were born that way. But Rogalski’s team found another possible explanation: A superager’s cortex doesn’t shrink as fast. Over 18 months, average 80-somethings experienced more than twice the rate of loss.

Another clue: Deeper in the brain, that attention region is larger in superagers, too. And inside, autopsies showed that brain region was packed with unusually large, spindly neurons – a special and little-understood type called von Economo neurons thought to play a role in social processing and awareness.

The superagers had four to five times more of these neurons than the typical octogenarian, Rogalski said – more even than the average young adult.

The Northwestern study isn’t the only attempt at unraveling long-lasting memory. At the University of California, Irvine, Dr. Claudia Kawas studies the oldest-old, people 90 and above. Some have Alzheimer’s. Some have maintained excellent memory and some are in between.

ALSO READ: Man Kaur: A 100-year-old runner wins three gold medals at the Americas Masters Games in Canada

About 40 percent of the oldest-old who showed no symptoms of dementia in life nonetheless have full-fledged signs of Alzheimer’s disease in their brains at death, Kawas told the AAAS meeting.

Rogalski also found varying amounts of amyloid and tau, hallmark Alzheimer’s proteins, in the brains of some superagers.

Now scientists are exploring how these people deflect damage. Maybe superagers have different pathways to brain health.

“They are living longer and living well,” Rogalski said. “Are there modifiable things we can think about today, in our everyday lives” to do the same? (VOA)

Next Story

Development of Alzheimer’s Disease Not Totally Linked to Genetics: Study

The research team analyzed the gene sequence and the biological age of the body's cells from blood

0
Genetics
With additional funding, researchers could further explore the interaction between Genetics and environment in the development of Alzheimer's disease and the impact of environmental factors in delaying the onset of this disorder. Pixabay

The colour of our eyes or the straightness of our hair is linked to our DNA, but the development of Alzheimer’s disease isn’t exclusively linked to Genetics, suggest new research.

In the first study published about Alzheimer’s disease among identical triplets, researchers found that despite sharing the same DNA, two of the triplets developed Alzheimer’s while one did not.

The two triplets that developed Alzheimer’s were diagnosed in their mid-70s, said the paper published in the journal Brain.

“These findings show that your genetic code doesn’t dictate whether you are guaranteed to develop Alzheimer’s,” said Dr Morris Freedman, head of neurology at Baycrest Centre for Geriatric Care.

“There is hope for people who have a strong family history of dementia since there are other factors, whether it’s the environment or lifestyle, we don’t know what it is, which could either protect against or accelerate dementia.”

All three, 85-year-old siblings had hypertension, but the two with Alzheimer’s had long-standing, obsessive-compulsive behaviour.

The research team analyzed the gene sequence and the biological age of the body’s cells from blood that was taken from each of the triplets, as well as the children of one of the triplet’s with Alzheimer’s.

Genetics
The colour of our eyes or the straightness of our hair is linked to our DNA, but the development of Alzheimer’s disease isn’t exclusively linked to Genetics, suggest new research. Pixabay

Among the children, one developed early onset Alzheimer’s disease at age 50 and the other did not report signs of dementia.

The research team also discovered that although the triplets were octogenarians at the time of the study, the biological age of their cells was six to ten years younger than their chronological age.

In contrast, one of the triplet’s children, who developed early onset Alzheimer’s, had a biological age that was nine years older than the chronological age.

The other child, who did not have dementia, of the same triplet showed a biological age that was close to their actual age.

Genetic
Your Genetic code doesn’t dictate whether you are guaranteed to develop Alzheimer’s Disease. Pixabay

“The latest genetics research is finding that the DNA we die with isn’t necessarily what we received as a baby, which could relate to why two of the triplets developed Alzheimer’s and one didn’t,” says Dr. Ekaterina Rogaeva, senior author on the paper and researcher at the University of Toronto’s Tanz Centre for Research in Neurodegenerative Diseases.

“As we age, our DNA ages with us and as a result, some cells could mutate and change over time”.

ALSO READ: Samsung India Renews its Focus on AC Business to Become Top Player

With additional funding, researchers could further explore the interaction between genetics and environment in the development of Alzheimer’s disease and the impact of environmental factors in delaying the onset of this disorder. (IANS)