Scientists at The Scripps Research Institute have developed a promising new compound derived from common herbs that could potentially lead to breakthrough treatments for Alzheimer's disease. The research team synthesized a stable derivative of carnosic acid—a molecule naturally found in rosemary and sage—and demonstrated significant cognitive improvements in mouse models of the neurodegenerative disorder.
The newly developed compound, called diAcCA, was administered to mice genetically modified to exhibit Alzheimer's-like symptoms over a three-month treatment period. Results of the study were recently published in the journal Antioxidants.
Significant Cognitive and Neurological Improvements
Mice receiving the diAcCA treatment showed remarkable improvements in learning and memory capabilities compared to untreated controls. More importantly, researchers observed increased density of synapses—the critical junctions where neurons connect and communicate—in the brains of treated mice.
"By combating inflammation and oxidative stress with this diAcCA compound, we actually increased the number of synapses in the brain," explained Stuart Lipton, a professor at Scripps Research and one of the study's authors. "We also took down other misfolded or aggregated proteins such as phosphorylated-tau and amyloid-β, which are thought to trigger Alzheimer's disease and serve as biomarkers of the disease process."
The reduction in amyloid plaques and tau tangles is particularly significant, as these protein accumulations are hallmark pathological features of Alzheimer's disease in humans. Synaptic loss strongly correlates with cognitive decline in Alzheimer's patients, making the observed increase in synaptic density a promising indicator of the compound's therapeutic potential.
Enhanced Stability and Bioavailability
While carnosic acid is known for its antioxidant and anti-inflammatory properties, its clinical utility has been limited by its very short shelf-life. The research team addressed this challenge by creating diAcCA, which can be taken orally before being converted into carnosic acid in the stomach and subsequently entering the bloodstream.
This innovative approach resulted in approximately 20% higher blood levels of the active compound compared to traditional ingestion of carnosic acid, enhancing its potential therapeutic efficacy.
Dramatic Cognitive Restoration
The cognitive improvements observed in the treated mice were substantial. "We did multiple different tests of memory, and they were all improved with the drug," Lipton noted. "And it didn't just slow down the decline; it improved virtually back to normal."
Importantly, the mice appeared to tolerate the diAcCA treatment well throughout the three-month study period, suggesting a favorable preliminary safety profile.
Addressing a Growing Global Health Crisis
The development comes at a critical time as Alzheimer's disease continues to pose an escalating public health challenge. The condition accounts for approximately 70% of all dementia cases worldwide. In Europe alone, Alzheimer's affects approximately 7 million people currently, with projections indicating this number could double to 14 million by 2030 due to the aging population.
While these preclinical results are encouraging, further research will be necessary to determine whether similar benefits can be achieved in human patients. The transition from successful mouse studies to effective human therapies remains one of the most challenging aspects of Alzheimer's drug development, with numerous promising candidates failing in late-stage clinical trials over the past decades.
Nevertheless, this herb-inspired approach represents an innovative direction in the search for effective Alzheimer's treatments, potentially offering new hope for patients and families affected by this devastating neurodegenerative disease.
