New brain cells in the old? Study stokes debate
New brain cells in the old? Study stokes debate
The report by scientists at Columbia University in New York, published in the journal Cell Stem Cell, runs directly counter to a different study published in Nature last month which found no evidence of new neurons are being created past the age of 13.
While neither study is seen as providing the definitive last word, the research is being closely watched as the world’s population ages and scientists seek to better understand how the brain ages for clues to ward off dementia.
The focal point of the research is the hippocampus, the brain’s center for learning and memory.
Specifically, researchers are looking for the foundations of new brain cells, including progenitor cells, or stem cells that would eventually become neurons.
Using autopsied brain samples from 28 people who died suddenly between the ages of 14-79, researchers looked at “newly formed neurons and the state of blood vessels within the entire human hippocampus soon after death,” said the Cell Stem Cell study.
“We found that older people have similar ability to make thousands of hippocampal new neurons from progenitor cells as younger people do,” said lead author Maura Boldrini, associate professor of neurobiology at Columbia University.
“We also found equivalent volumes of the hippocampus across ages.”
The findings suggest that many seniors may retain more of their cognitive and emotional abilities longer than previously believed.
However, Boldrini cautioned that these new neurons might be less adept at making new connections in older people, due to aging blood vessels.
Animals like mice and monkeys tend to lose the ability to generate new brain cells in the hippocampus with age.
Just how the human brain reacts to aging has been controversial, though the widely held view is that the human brain does indeed continue to generate neurons into adulthood, and that this “neurogenesis” could one day help scientists tackle age-related brain degeneration.
A study last month led by Arturo Alvarez-Buylla of the University of California in San Francisco found the opposite, however.
Looking at brain samples from 59 adults and children, “we found no evidence of young neurons or the dividing progenitors of new neurons” in the hippocampi of people older than 18, he told AFP when the study was published.
They did find some in children between birth and one year, “and a few at seven and 13 years of age,” he said.
That study was described by experts as “sobering,” because it indicated the human hippocampus is largely generated during fetal brain development.
Alvarez-Buylla’s lab responded to the latest research in a statement, saying that they were unconvinced Columbia University had found conclusive evidence of adult neurogenesis.
“Based on the representative images they present, the cells they call new neurons in the adult hippocampus are very different in shape and appearance from what would be considered a young neuron in other species,” their response, published by the Los Angeles Times, said.
Boldrini, for her part, said her team used flash-frozen brain samples, while the California researchers used samples that were chemically preserved in a process that may have obscured the detection of new neurons.
SpaceX’s first private passenger is Japanese fashion magnate Maezawa
- SpaceX in February transfixed a global audience with the successful test launch of its Falcon Heavy, the most powerful operational rocket in the world
- SpaceX has already upended the space industry with its relatively low-cost reusable Falcon 9 rockets
HAWTHORNE, California: SpaceX, Elon Musk’s space transportation company, on Monday named its first private passenger as Japanese businessman Yusaku Maezawa, the founder and chief executive of online fashion retailer Zozo.
A former drummer in a punk band, billionaire Maezawa will will take a trip around the moon aboard its forthcoming Big Falcon Rocket spaceship, taking the race to commercialize space travel to new heights.
The first passenger to travel to the moon since the United States’ Apollo missions ended in 1972, Maezawa’s identity was revealed at an event Monday evening at the company’s headquarters and rocket factory in the Los Angeles suburb of Hawthorne.
In moves typical of his publicity-seeking style, Musk, who is also the billionaire chief executive of electric car maker Tesla Inc, had previously teased a few tantalizing details about the trip and the passenger’s identity, but left major questions unanswered.
On Thursday, Musk tweeted a picture of a Japanese flag. He followed that up on Sunday with tweets showing new artist renderings of the Big Falcon Rocket, or BFR, the super heavy-lift launch vehicle that Musk promises will shuttle the passenger to the moon and eventually fly humans and cargo to Mars, using the hashtag #OccupyMars.
While the BFR has not been built yet, Musk has said he wants the rocket to be ready for an unpiloted trip to Mars in 2022, with a crewed flight in 2024, though his ambitious production targets have been known to slip.
SpaceX plans a lunar orbit mission. It was not clear how much Maezawa paid for the trip.
Maezawa made his fortune by founding the wildly popular shopping site Zozotown. His company Zozo, officially called Start Today Co. Ltd, also offers a made-to-measure service using a polka dot bodysuit, the Zozosuit..
With SpaceX, Amazon.com founder Jeff Bezos’ Blue Origin and entrepreneur Richard Branson’s Virgin Galactic battling it out to launch private-sector spacecraft, the SpaceX passenger will join a growing list of celebrities and the ultra-rich who have secured seats on flights offered on the under-development vessels.
Those who have signed up to fly on Virgin Galactic sub-orbital missions include actor Leonardo DiCaprio and pop star Justin Bieber. A 90-minute flight costs $250,000.
Short sightseeing trips to space aboard Blue Origin’s New Shepard rocket are likely to cost around $200,000 to $300,000, at least to start, Reuters reported in July.
SpaceX has already upended the space industry with its relatively low-cost reusable Falcon 9 rockets. The company has completed more than 50 successful Falcon launches and snagged billions of dollars’ worth of contracts, including deals with NASA and the US Department of Defense.
SpaceX in February transfixed a global audience with the successful test launch of its Falcon Heavy, the most powerful operational rocket in the world.
SpaceX previously announced plans to eventually use Falcon Heavy to launch paying space tourists on a trip around the moon, but Musk said in February he was inclined to reserve that mission for the BFR.