What has killing countless animals in Alzheimer’s experiments taught researchers about the disease? Honestly, not much.
After decades of wasted time and money, more than 100 unsuccessful drugs, and an untold number of animals’ lives taken, no cure for Alzheimer’s disease or method of slowing its progression in humans has been found.
Here are five things revealed by the overwhelming failure of using animal models for Alzheimer’s research:
1. Mice, rats, monkeys, dogs, and other animals don’t naturally develop Alzheimer’s disease.
Mice are quick learners and caring parents, and they even sing to their mates. They’re wonderfully complex and interesting. But just because they have thoughts and emotions just like humans doesn’t mean we share the same physiology.
Experimenters manipulate the genome of mice and other animals to force amyloid plaques to build up in their brains, just as they build up in the brains of humans with Alzheimer’s disease. While these mutilated animals may have symptoms that resemble those of Alzheimer’s, they don’t actually have the disease.
Studies have shown that trial drugs that remove toxic amyloid-beta protein from animal brains can help the animal. However, these same drugs do not help human patients with memory loss or cognitive problems.
2. Some treatments that have worked in animal trials have actually hurt human patients with Alzheimer’s.
While a compound of drugs known as BACE inhibitors tested successfully in mice who’d been genetically altered to develop a pseudo-Alzheimer’s condition, these drugs actually appeared to worsen human patients’ cognitive abilities and potentially exacerbate brain shrinkage. Three pharmaceutical companies echoed this same stunning failure.
3. The failure rate in humans for new Alzheimer’s drugs is a staggering 99%.
According to the Allen Institute, Alzheimer’s affects roughly 5.8 million Americans. It, along with other forms of dementia, costs the U.S. an estimated $290 billion every year. Despite this grave reality, no therapy exists to slow down the disease’s progression.
4. Archaic animal testing failed. Curing Alzheimer’s requires a 21st century approach.
As Allen Institute for Brain Science Senior Investigator Ed Lein stated, “We’re trying to cure a disease of a complex system we fundamentally don’t understand.”
Bradley Hyman, a professor of neurology and Alzheimer’s researcher at Harvard Medical School and Massachusetts General Hospital, furthered this point, adding that the complexity of Alzheimer’s disease makes it “very difficult to model in experimental systems.” He says,
“[D]irect examination of the human brain is without a doubt crucial to understanding the disease.”
5. We must stop killing animals and actually focus on the HUMAN brain.
Alzheimer’s studies using non-animal research methods have already led to important discoveries.
For example, for the first time, researchers have used human data from post-mortem brain samples to quantify the speed of different processes that lead to Alzheimer’s disease. They found that it develops in a very different way than previously thought. Rather than originating in a single location in the brain—which is the case in mice—and then spreading out, Alzheimer’s disease in humans reaches multiple regions of the brain early on in its progression.
Other promising human-relevant studies are currently underway. With a $40.5 million grant from the National Institutes of Health, researchers are reportedly using tissue from brains donated by people who died with Alzheimer’s to study how the disease takes root in the brain.
Lead investigator Lein told NPR that researchers have mistakenly been “trying to go right to the cure without really understanding the brain and what actually goes wrong that leads to dementias.”
One goal of the new consortium is to identify abnormal cells before any symptoms of Alzheimer’s start to appear. “If we can find the cells where something goes wrong, this would provide a new way to try to treat this disease,” Lein said.
Help PETA Push for Modern Research
Our fellow animals have complex lives and interests as well as families of their own—they are not test tubes. It’s time to replace cruel, ineffective experiments on other animals with modern research methods that can actually help us understand and treat human conditions.
Urge your congressional representatives to support PETA’s Research Modernization Deal, which outlines a plan to revamp laboratory research: