Infectious Theory of Alzheimer’s Disease Receives Some Attention with $1 Million Prize
The predominant theory behind the causes of Alzheimer’s disease is related to the accumulation of a type of protein in the brain of patients called beta-amyloid. This theory has come under criticism lately, largely due to the lack of success of a number of drugs that prevent or clear beta-amyloid in late-stage clinical trials. Later in the disease, another tangle of a different type of protein, tau, shows up in the disease.
Over the last 20 years or so, a theory circles around that the instigating factor in Alzheimer’s disease might be an infectious agent. And it’s back. A recent article on National Public Radio looks at this theory and profiles a man who is offering $1 million of his own money to researchers who can provide good data proving it.
Leslie Norins is a medical publisher and editor who received his medical degree from Duke University Medical School and his PhD from the University of Melbourne in Australia, where he focused on immunology. He spent seven years running a laboratory at the U.S. Centers for Disease Control and Prevention (CDC) before going into medical publishing.
He is the founder and president of Alzheimer’s Germ Quest, Inc., a public benefit corporation formed in 2017 to “accelerate research on possible infectious causes of Alzheimer’s disease.”
In 2014, Norins became interested in the possible link between infectious diseases and Alzheimer’s and made a two-year review of the scientific literature on the subject. He thought he found a pattern. He told NPR, “It appeared that many of the reported characteristics of Alzheimer’s disease were compatible with an infectious process. I thought for sure this must have already been investigated, because millions and millions of dollars have been spent on Alzheimer’s research.”
There has been research, but it has not been a large focus. In a 2018 article in the Journal of Alzheimer’s Disease by Aristo Vojdani, chief executive officer of Immunosciences Lab in Los Angeles and a faculty member at Loma Linda University, with his colleagues, wrote, “As early as the 1980s, molecular virologist, Ruth Itzhaki began to investigate if there was a causal connection between infections and neurodegenerative disorder. Although the theory has yet to be universally embraced, in 2017 Itzhaki and 33 other scientists from all over the world published a review article in this very journal presenting evidence for the causal role of pathogens in Alzheimer’s disease (AD).”
After his review of the literature, Norins is convinced that a single infectious agent, which hasn’t been specified or possibly even discovered, causes Alzheimer’s disease, which for his purposes he’s dubbed the “Alzheimer’s Germ.”
One example of supporting work is a study published in Neuron in June suggesting that viral infection influences Alzheimer’s disease progression. Researchers from the Icahn School of Medicine at Mount Sinai evaluated data on the brains of 622 people who had indications of Alzheimer’s and 322 people who did not. They found levels of herpes virus in the Alzheimer’s patients that were up to twice as high as the non-disease group.
Joel Dudley, co-author of the study, said in a statement in June, “I don’t think we can answer whether herpes viruses are a primary cause of Alzheimer’s disease. But what’s clear is that they’re perturbing networks and participating in networks that directly accelerate the brain towards the Alzheimer’s topology.”
Dudley told CNN, “The title of the talk that I usually give is, ‘I Went Looking for Drug Targets, and All I Found Were These Lousy Viruses.’”
He suspects the study results could assist in identifying virus biomarkers that might help diagnose Alzheimer’s and assess an individual’s risk for the disease.
“This is the most compelling evidence ever presented that points to a viral contribution to the cause or progression of Alzheimer’s,” said co-author Sam Gandy, professor of neurology and psychiatry and director of the Center for Cognitive Health at Mount Sinai in New York, reports CNN.
In response to Dudley’s article, Keith Fargo, director of scientific programs and outreach for the Alzheimer’s Association, noted that much more work would need to be done to prove a connection between herpes viruses and Alzheimer’s. “However, if viruses or other infections are confirmed to have roles in Alzheimer’s, it may enable researchers to find new antiviral or immune therapies to treat or prevent the disease. The Alzheimer’s Association welcomes new ideas in the Alzheimer’s field and new avenues to pursue for potential treatments and prevention strategies.”
And although Norins $1 million award is eye-opening, it’s a drop in the bucket compared to the $2 billion the National Institutes of Health (NIH) spends on amyloid and tau research.
James Burke, professor of medicine and psychiatry at Duke University’s Alzheimer’s Disease Research Center, told NPR he wasn’t willing to abandon the amyloid theory completely, but said, “There may be many roads to developing Alzheimer’s disease and it would be shortsighted to focus just on amyloid and tau. A million-dollar prize is attention-getting but the reward for identifying a treatable target to delay or prevent Alzheimer’s disease is invaluable.”