News / Health

Scientists Discover Key to Normal Memory Lapses in Seniors

FILE- Researcher holds human brain in laboratory at Northwestern University's cognitive neurology and Alzheimer's disease center, Chicago, July 29, 2013.
FILE- Researcher holds human brain in laboratory at Northwestern University's cognitive neurology and Alzheimer's disease center, Chicago, July 29, 2013.
Reuters
Scientists have good news for all the older adults who occasionally forget why they walked into a room — and panic that they are getting Alzheimer's disease.
Not only is age-related memory loss a syndrome in its own right and completely unrelated to that dread disease, but unlike Alzheimer's it may be reversible or even preventable, researchers led by a Nobel laureate said in a study published on Wednesday.

Using human brains that had been donated to science as well as the brains of lab mice, the study for the first time pinpointed the molecular defects that cause cognitive aging.

In an unusual ray of hope for a field that has had almost nothing to offer older adults whose memory is failing, the study's authors conclude that drugs, foods or even behaviors might be identified that affect those molecular mechanisms, helping to restore memory.

Any such interventions would represent a significant advance over the paltry offerings science has come up with so far to prevent memory decline, such as advice to keep cognitively active and healthy — which helps some people, but not all, and has only a flimsy scientific foundation. By identifying the “where did I park the car?” molecule, the discovery could also kick-start the mostly moribund efforts to develop drugs to slow or roll back the memory lapses that accompany normal aging.

“This is a lovely set of studies,” said Molly Wagster of the National Institute on Aging, an expert on normal age-related memory decline who was not involved in the new study. “They provide clues to the underlying mechanism of age-related memory decline and will, hopefully, move us down the road toward targeted therapeutics.”

About 40 percent of Americans age 85 and older say they experience some memory loss, a 2009 survey by the Pew Research Center found, as did 27 percent of those 75 to 84 and 20 percent of those ages 65 to 74.

Brain bank

The researchers began with eight brains from the New York Brain Bank at Columbia University donated by people aged 33 to 88 who were free of brain disease when they died. They extracted two structures in the hippocampus, a vital cog in the brain's memory machinery: the dentate gyrus, a boomerang-shaped region whose function declines with age but is not affected by Alzheimer's, and the entorhinal cortex, which is largely unaffected by aging but is where Alzheimer's first takes hold, killing neurons.

The scientists then measured which genes had been active in each structure, and found one suspicious difference: 17 genes in the dentate gyrus became more active, or less, as the age of the brain increased.

The most significant change was that the gene for a protein called RbAp48 had essentially retired: The gene's activity tailed off dramatically the older a brain got. As a result, old brains had about half the RbAp48 of young brains, the scientists report online in the journal Science Translational Medicine.

The scientists then sampled 10 more healthy human brains, ranging from 41 to 89 years at the time of death. Once again, the amount of RbAp48 protein declined with age in the dentate gyrus. They next confirmed that RbAp48 protein was also less abundant in the dentate gyrus of old mice compared to young ones.

For the final step, the scientists had to nail down whether the missing protein caused age-related memory loss. They genetically engineered mice whose RbAp48 genes were disabled. Result: The young mice had memories as poor as animals four times their age (the mouse equivalent of late middle age), and they had terrible trouble navigating a water maze or differentiating objects they had seen before from novel ones.

Crucially, the scientists also did the reverse experiment, engineering mice so their brains had extra doses of RbAp48. The mice's memories returned to the flower of youth.

“With RbAp48, we were able to reverse age-related memory loss in the mice,” said Columbia's Dr. Eric Kandel, who shared the 2000 Nobel Prize in medicine for discoveries of the molecular basis of memory and led the research. “Unlike in Alzheimer's, there is no significant cell death in age-related memory loss, which gives us hope it can be prevented or reversed.”

Exactly how RbAp48 does that is not clear. The protein acts as a sort of genetic master key: By causing chromosomes to loosen their hold on the molecular spool they are wound around like thread, it allows genes to be turned on. Among the activated genes, Kandel explained, are those involved in forming memories.

The emerging picture is that levels of RbAp48 decline with age, allowing chromosomes to maintain a death grip on their spools. Memory genes remain dormant, and you can't remember that you promised your spouse you would make dinner.

The researchers plan to see what social and dietary factors might boost RbAp48 in mice, said Kandel, who will be 84 in November. Pharmaceuticals, nutraceuticals, physical and cognitive exercise are all candidates, said Columbia's Dr. Scott Small, co-senior author of the study.

Testing such interventions in mice should be more useful to humans than tests of drugs for Alzheimer's, he said. RbAp48 “is different,” Small said. “Alzheimer's does not occur naturally in the mouse. Here, we've caused age-related memory loss in the mouse, and we've shown it to be relevant to human aging.”

You May Like

Missouri Town Braces for Possible Racial Unrest

Situation in Ferguson hinges on whether white police officer will be indicted for August shooting death of unarmed black teen; decision could come Monday More

Video Ukraine Marks Anniversary of 1930s Deadly Famine

President Poroshenko compares Soviet-era ‘genocide’ to current tactics of pro-Russia rebels in Ukraine's east More

S. Philippines Convictions Elusive 5 Years After Election-related Killings

Officials vowed to deliver justice as the nation marked the anniversary of the country's worst political massacre that left 58 dead, more than half media More

This forum has been closed.
Comment Sorting
Comments
     
by: Julie from: New York
August 30, 2013 7:09 AM
Staying healthy is essential especially as you age and the best way to do that is to stay physically active, eat the right things and keep mentally sharp. I just checked out the site Retirement And Good Living that has some great pages and post on exercise, mental health and nutrition as well as many other retirement related topics including various games to keep your mind active.

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Ukraine Marks Anniversary of Deadly 1930s Faminei
X
Daniel Schearf
November 23, 2014 4:32 PM
During a commemoration for millions who died of starvation in Ukraine in the early 1930s, President Petro Poroshenko lashed out at Soviet-era totalitarianism for causing the deaths and accused today’s Russian-backed rebels in the east of using similar tactics. VOA’s Daniel Shearf reports from Kyiv.
Video

Video Ukraine Marks Anniversary of Deadly 1930s Famine

During a commemoration for millions who died of starvation in Ukraine in the early 1930s, President Petro Poroshenko lashed out at Soviet-era totalitarianism for causing the deaths and accused today’s Russian-backed rebels in the east of using similar tactics. VOA’s Daniel Shearf reports from Kyiv.
Video

Video Hong Kong Protests at a Crossroads

New public opinion polls in Hong Kong indicate declining support for pro-democracy demonstrations after weeks of street protests. VOA’s Bill Ide in Guangzhou and Pros Laput in Hong Kong spoke with protesters and observers about whether demonstrators have been too aggressive in pushing for change.
Video

Video Law Enforcement, Activists in Ferguson Agree to Keep Peace

Authorities in Ferguson, Missouri, say they have agreed with protest leaders to maintain peace when a grand jury reaches its decision on whether to indict a white police officer in the shooting death of a black teenager. Ferguson, a suburb of St. Louis, has been the scene of intermittent violence since the August 9 shooting intensified long-simmering antagonism between the police and the African-American community. VOA's Zlatica Hoke reports.
Video

Video US Immigration Relief Imminent for Mixed-Status Families

Tens of thousands of undocumented immigrants in the Washington, D.C., area may benefit from a controversial presidential order announced this week. It's not a path to citizenship, as some activists hoped. But it will allow more immigrants who arrived as children or who have citizen children, to avoid deportation and work legally. VOA's Victoria Macchi talks with one young man who benefited from an earlier presidential order, and whose parents may now benefit after years of living in fear.
Video

Video New Skateboard Defies Gravity

A futuristic dream only a couple of decades ago, the hoverboard – a skateboard that floats above the ground - has finally been made possible. While still not ready for mass production, it promises to become a cool mode of transport... at least over some surfaces. VOA’s George Putic reports.
Video

Video Falling Gas Prices Impact US Oil Extraction

With the price of oil now less than $80 a barrel, motorists throughout the United States are benefiting from gas prices below $3 a gallon. But as VOA’s Kane Farabaugh reports, the decreasing price of petroleum has a downside for the hydraulic fracturing industry in the United States.
Video

Video Tensions Build on Korean Peninsula Amid Military Drills

It has been another tense week on the Korean peninsula as Pyongyang threatened to again test nuclear weapons while the U.S. and South Korean forces held joint military exercises in a show of force. VOA’s Brian Padden reports from the Kunsan Air Base in South Korea.
Video

Video Mama Sarah Obama Honored at UN Women’s Entrepreneurship Day

President Barack Obama's step-grandmother is in the United States to raise money to build a $12 million school and hospital center in Kogelo, Kenya, the birthplace of the president's father, Barack Obama, Sr. She was honored for her decades of work to aid poor Kenyans at a Women's Entrepreneurship Day at the United Nations.
Video

Video Gay Evangelicals Argue That Bible Does Not Condemn Homosexuality

More than 30 U.S. states now recognize same-sex marriages, and an increasing number of mainline American churches are blessing them. But evangelical church members- which account for around 30 percent of the U.S. adult population - believe the Bible unequivocally condemns homosexuality. VOA's Jerome Socolovsky reports that gay, lesbian, bisexual and transgender evangelicals are coming out. Backed by a prominent evangelical scholar, they argue that the traditional reading of the bible is wrong.
Video

Video Ebola Economic Toll Stirs W. Africa Food Security Concerns

The World Bank said Wednesday that it expects the economic impact of the Ebola outbreak on the sub-Saharan economy to cost somewhere betweenf $3 billion to $4 billion - well below a previously-outlined worst-case scenario of $32 billion. Some economists, however, paint a gloomier picture - warning that the disruption to regional markets and trading is considerable. Henry Ridgwell reports from London.
Video

Video Chaos, Abuse Defy Solution in Libya

The political and security crisis in Libya is deepening, with competing governments and, according to Amnesty International, widespread human rights violations committed with impunity. VOA’s Al Pessin reports from London.
Video

Video US Hosts Record 866,000 Foreign Students

Close to 900,000 international students are studying at American universities and colleges, more than ever before. About half of them come from Asia, mostly China. The United States hosts more foreign students than any other country in the world, and its foreign student population is steadily growing. Zlatica Hoke reports.

All About America

AppleAndroid