Toxic Caterpillars and Alzheimer’s Biomarkers

Grind for July 15th
“High heels were invented by a woman who had been kissed on the forehead.”
– Christopher Morley

Medical News

The Headline

Scientists look for biomarkers to improve Alzheimer’s diagnosis

The Grind

One of the reasons Alzheimer’s is so hard to diagnose is that it begins to alter the brain long before symptoms appear. Before the patient experiences memory loss, the brain will experience a buildup of toxic proteins, inflammation, and damage to the synapses.

Tests that detect these changes rely on biological markers or “biomarkers” that signal the progression of Alzheimer’s.

For example, the biomarker test Amyvid (approved in 2012) reveals the presence of amyloid in the brain. Clumps of amyloid are a hallmark of the disease.

Amyvid is 98% accurate but costs thousands of dollars because it requires a PET scan.

The Details

Researchers at the Alzheimer’s Drug Discovery Foundation are working on a new test that detects tau, a toxic protein that kills brain cells. A biomarker for tau could make diagnosis easier and spur the development of drugs to remove tau from the brain.

“For the future, we hope that we might be able to use these biomarkers in order to stop or delay the memory changes from ever happening,” says Maria Carrillo, chief scientist at the Alzheimer’s Association.

Several pharmaceutical companies are close to gaining FDA approval for injected dyes that reveal tau in patients during PET scans; but to make the process less expensive, scientists hope to use biomarkers in the blood to assess levels of amyloid and tau in the brain.

“We treat high cholesterol to reduce the risk of heart attack,” says Carrillo. “And someday it may be possible to reduce the risk of dementia by treating high levels of amyloid, tau, or inflammation in the brain.”

As Carrillo explains, each new test must undergo human trials on several demographics. “What may represent as a biomarker in one population may not actually hold true in another, and we’ve seen this in other diseases.”

In the meantime, the team is still searching for biomarkers for inflammation and synapse damage as well as a way to accurately measure a person’s mental function separate from the biomarker tests.

Creepy Crawly

The Headline

A plague of toxic caterpillars is spreading through Europe

The Grind

Europe’s mild winter and warm spring have generated a significant boost in the population of oak processionary caterpillars – whose toxic hairs can elicit eye irritation, coughing, skin rash, fever, dizziness, asthma attacks, and allergic reaction. The toxin can also affect dogs and cats.

The black and white caterpillars, which like to gather at the tops of oak trees, are an invasive species that measure about one inch in length.

Each individual caterpillar has up to 700,000 toxic hairs, which are nearly invisible and can spread in the wind. They have few natural predators, as most birds know not to eat them.

The Details

In Germany, the increased prevalence of the caterpillars has forced officials to close schools, parks, pools, restaurants, and even sections of roadway.

The Fredenbaumpark in Dortmund was closed for nearly one month as specialists worked to destroy an estimated 500 caterpillar nests.

“The oak processionary infestation this year is very intensive – much more than last year,” says park manager Frank Dartsch.

In Münster, at least six people have had eye surgery to remove caterpillar hairs. In Mülheim, nine children were taken to the hospital in June after the toxin caused breathing problems during a sporting event.

Specialists called in to combat the bugs use firefighters’ lifts to reach the nests and then attack them using blowtorches and vacuums. In Frankfurt, authorities are spraying biocide from helicopters in a desperate effort to stop the infestation.

The caterpillars will begin to pupate this month, but their nests can remain active (and toxic) for years after the bugs turn into moths.

Did you know… Every hour one billion cells in the body must be replaced.