Saturday October 20, 2018
Home Science & Technology Scientists de...

Scientists develop a Drug likely to benefit people with Alzheimer’s Disease

0
//
160
FILE - An image shows activity in a human brain. Scientists have developed a drug capable of sweeping away abnormal protein clumps in the brain which are a hallmark of Alzheimer’s disease. VOA
Republish
Reprint

Washington, Jan 27, 2017: Scientists have developed a drug they hope will benefit people with Alzheimer’s disease, which afflicts an estimated 44 million people around the world. The new compound sweeps away abnormal protein clumps in the brain which are a hallmark of the neurodegenerative disorder.

In a study reported in the journal Science Translational Medicine, researchers describe how a synthetic drug, called antisense oligoneucleotide, reduced the production and in some cases cleared clumps of tau in the brain.

NewsGram brings to you current foreign news from all over the world.

Tau bundles are one of the hallmarks of the disease, along with beta amyloid deposits, another destructive protein.

By stopping the formation of tau, researchers at Washington University School of Medicine in St. Louis, Missouri, found they could extend the lives of mice that were bred to have collections of human tau in their brains.

Lead author Sara DeVos said scientists saw an improvement in their condition.

“So these mice die earlier than normal. So when we treat with our drug, the mice live longer and we can also prevent neurons from dying. So if we give this drug, the neurons will no longer die as a result of these tau bundles,” said DeVos

NewsGram brings to you top news around the world today.

The investigators also tested the compound in monkeys and saw positive results.

FILE – Patients with Alzheimer’s and dementia are seen during a therapy session. Alzheimer’s afflicts an estimated 44 million people around the world. VOA

Human testing expected soon

Antisense oligneucleotide targets the genetic instructions for building tau. The molecule binds to messenger RNA, which carries out the DNA blueprint for life, preventing tau from being produced. The drug can be made to target RNA for destruction of any protein, said scientists.

Tim Miller, a professor of neurology at Washington University and senior author of the study, hopes the drug, developed with Ionis Pharmaceuticals, will soon be tested in humans with Alzheimer’s disease.

“The most exciting and most interesting … is to apply this to people who we presume have abnormal tau to test the hypothesis whether lowering tau in those people will be of benefit to those people,” he said.

Check out NewsGram for latest international news updates.

Other types of antisense oligoneucleotides have been approved by U.S. regulators and are being used to treat the neurodegenerative disease muscular dystrophy and spinal muscular atrophy. The compound is in clinical trials for Huntington’s disease and ALS, also known as Lou Gehrig’s disease.

Because tau deposits are only a piece of the puzzle that causes Alzheimer’s, the investigators envision using the drug with other treatments, also in development.

There is no cure for Alzheimer’s disease, which primarily strikes senior adults, leading to a decline in mental functioning and eventually death. (VOA)

Click here for reuse options!
Copyright 2017 NewsGram

Next Story

Invasive Species May Not Be All Bad: Scientists

An active debate among biologists about the role of invasive species in a changing world is going on

0
Invasive Species
The invasive European green crab is tearing down ecosystems in Newfoundland and building them up on Cape Cod. VOA

Off the shores of Newfoundland, Canada, an ecosystem is unraveling at the hands (or pincers) of an invasive crab.

Some 1,500 kilometers (930 miles) to the south, the same invasive crab — the European green crab — is helping New England marshes rebuild.

Both cases are featured in a new study that shows how the impacts of these alien invaders are not always straightforward.

Around the world, invasive species are a major threat to many coastal ecosystems and the benefits they provide, from food to clean water. Attitudes among scientists are evolving, however, as more research demonstrates that they occasionally carry a hidden upside.

“It’s complicated,” said Christina Simkanin, a biologist at the Smithsonian Environmental Research Center, “which isn’t a super-satisfying answer if you want a direct, should we keep it or should we not? But it’s the reality.”

Simkanin co-authored a new study showing that on the whole, coastal ecosystems store more carbon when they are overrun by invasive species.

Good news, crab news

Take the contradictory case of the European green crab. These invaders were first spotted in Newfoundland in 2007. Since then, they have devastated eelgrass habitats, digging up native vegetation as they burrow for shelter or dig for prey. Eelgrass is down 50 percent in places the crabs have moved into. Some sites have suffered total collapse.

That’s been devastating for fish that spend their juvenile days among the seagrass. Where the invasive crabs have moved in, the total weight of fish is down tenfold.

The loss of eelgrass also means these underwater meadows soak up less planet-warming carbon dioxide from the atmosphere.

In Cape Cod, Massachusetts, the same crab is having the opposite impact.

Off the coast of New England, fishermen have caught too many striped bass and blue crabs. These species used to keep native crab populations in check. Without predators to hold them back, native crabs are devouring the marshes.

But the invasive European green crab pushes native crabs out of their burrows. Under pressure from the invader, native crabs are eating less marsh grass. Marshes are recovering, and their carbon storage capacity is growing with them.

Invasive species
In this May 8, 2016 photo, eelgrass grows in sediment at Lowell’s Cove in Harpswell, Maine. VOA

Carbon repositories

Simkanin and colleagues compiled these studies and more than 100 others to see whether the net impact on carbon storage has been positive or negative.

They found that the ones overtaken by invasive species held about 40 percent more carbon than intact habitats.

They were taken by surprise, she said, because “non-native species are thought of as being negative so often. And they do have detrimental impacts. But in this case, they seem to be storing carbon quicker.”

At the Smithsonian Environmental Research Center where she works, the invasive reed Phragmites has been steadily overtaking a marsh scientists are studying.

Phragmites grows much taller, denser and with deeper roots than the native marsh grass it overruns.

But those same traits that make it a powerful invader also mean it stores more carbon than native species.

“Phragmites has been referred to as a Jekyll and Hyde species,” she said.

Not all invaded ecosystems stored more carbon. Invaded seagrass habitats generally lost carbon, and mangroves were basically unchanged. But on balance, gains from marsh invaders outweighed the others.

Invasive species
Phragmites plants growing on Staten Island draft in a breeze in the Oakwood Beach neighborhood of Staten Island. VOA

Not a lot of generalities

To be clear, Simkanin said the study is not suggesting it’s always better to let the invaders take over; but, it reflects an active debate among biologists about the role of invasive species in a changing world.

“One of the difficult things in the field of invasion biology is, there aren’t a lot of generalities,” said Brown University conservation biologist Dov Sax, who was not involved with the research. “There’s a lot of nuance.”

The prevailing view among biologists is that non-native species should be presumed to be destructive unless proven otherwise.

When 19 biologists wrote an article in 2011 challenging that view, titled, “Don’t judge species on their origins,” it drew a forceful rebuke from 141 other experts.

Sax said the argument is likely to become more complicated in the future.

Also Read: Climate Change Not A Hoax: Trump

“In a changing world, with a rapidly changing climate, we do expect there to be lots of cases where natives will no longer be as successful in a region. And some of the non-natives might actually step in and play some of those ecosystem services roles that we might want,” he said.

“In that context, what do we do? I definitely don’t have all the answers.” (VOA)