Scientists Discover a New Way to Stop Alzheimer's Before Memory Loss Starts

Scientists at Northwestern University have identified a previously unknown toxic protein that appears to trigger Alzheimer's disease years before memory loss begins. Their experimental drug, called NU-9, successfully blocked this early damage in mice and dramatically reduced brain inflammation linked to disease progression.

What Makes This Discovery Different from Previous Alzheimer's Research?

Unlike traditional approaches that target the disease after symptoms appear, this research focuses on the earliest stages of Alzheimer's—decades before cognitive decline becomes noticeable. The team discovered a highly toxic subspecies of amyloid beta oligomers, toxic clusters of peptides that drive several of the brain's earliest changes including neuronal dysfunction and immune cell activation.

"Alzheimer's disease begins decades before its symptoms appear, with early events like toxic amyloid beta oligomers accumulating inside neurons and glial cells becoming reactive long before memory loss is apparent," said Daniel Kranz, the study's first author and recent Ph.D. graduate from Northwestern's Interdisciplinary Biological Sciences program.

How Does the NU-9 Drug Actually Work?

The experimental drug NU-9 works by rescuing the cellular pathway that normally clears toxic proteins from the brain. In both amyotrophic lateral sclerosis (ALS) and Alzheimer's disease, cells suffer from toxic protein buildup because their natural cleanup mechanism gets damaged. NU-9 essentially repairs this broken system.

When researchers administered NU-9 to pre-symptomatic mice for 60 days, the results were remarkable. The drug achieved several key improvements:

• Inflammation Reduction: NU-9 significantly reduced early reactive astrogliosis, an inflammatory reaction that typically begins long before symptoms appear
• Toxic Protein Clearance: The number of toxic amyloid beta oligomers bound to astrocytes (star-shaped brain cells that protect neurons) plummeted dramatically
• Brain-Wide Protection: An abnormal form of the protein TDP-43, linked to cognitive impairments, sharply decreased across multiple brain regions

The improvements spanned multiple regions of the brain, indicating that NU-9 has a brain-wide anti-inflammatory effect that could prevent the cascade of toxic events that ultimately destroy neurons.

What Is This Hidden Toxic Protein That Starts Alzheimer's?

The Northwestern scientists discovered a uniquely problematic subtype of amyloid beta oligomers called ACU193+, named after the antibody that detects it. This subtype shows up early inside stressed neurons, then appears to migrate to the surfaces of nearby astrocytes. When these oligomers latch onto astrocytes, they may spark a cascade of inflammation that spreads throughout the brain, long before memory loss begins.

"We identified a distinct amyloid beta oligomer subtype that appears inside neurons and on nearby reactive astrocytes very early in the disease," Kranz explained. "It potentially acts as an instigator of early Alzheimer's pathology."

This discovery represents a major shift in understanding Alzheimer's progression. For decades, scientists considered all amyloid beta oligomers equally toxic, but this research reveals that not all oligomers are the same—and some are far more dangerous than others.

The research comes at a time when Alzheimer's treatment is experiencing unprecedented progress. Recent breakthroughs include Food and Drug Administration (FDA) approval of anti-amyloid immunotherapies like lecanemab and donanemab, which have shown they can slow cognitive decline by approximately 30% in early-stage patients. However, these treatments work after symptoms begin, while NU-9 targets the disease at its very earliest stages.

Richard Silverman, who invented NU-9 and previously created pregabalin (Lyrica) for treating fibromyalgia and nerve pain, compared the approach to preventive medicine for heart disease. "Most people are used to monitoring their cholesterol levels," Silverman said. "If you have high cholesterol, it doesn't mean that you will have a heart attack soon. But it's time to take drugs to lower your cholesterol levels to prevent that heart attack from happening down the road. NU-9 could play a similar role."

The drug has already received FDA clearance to begin human clinical trials for ALS in 2024, and researchers are hopeful it could play a similar prophylactic role for Alzheimer's disease. With early diagnostic blood tests for Alzheimer's becoming more available, people could potentially start taking NU-9 before symptoms appear, fundamentally changing how we approach this devastating disease.