A Promising New Drug Shows Potential for Treating Cognitive Decline in Parkinson’s Disease
Parkinson’s disease is known for its impact on motor skills, but it also affects mood and cognition. Researchers at the University of Arizona have been exploring a new drug, PNA5, that shows promise in improving memory in models of vascular dementia and mice with Parkinson’s-like symptoms.
PNA5 is a short peptide that targets a key receptor linked with blood pressure. It has shown an ability to reverse cognitive decline in mice by reducing the activity of microglia cells in the hippocampus, which are believed to contribute to cognitive decline when overactivated.

Neurobiologist Kelsey Bernard explains, “With PNA5, we’re targeting cognitive symptoms and aiming to prevent further degeneration. By taking a protective approach, we hope to halt cognitive decline progression.”
Studies have shown that PNA5 improves recognition memory, spatial working memory, and slows the loss of brain cells in the hippocampus. By calming microglia cells and reducing inflammation in the brain, PNA5 may help mitigate the damage caused by an overactive immune response.
Madhavan adds, “When patients are diagnosed with Parkinson’s disease, cognitive impairment is already present in a significant percentage. Unfortunately, there are currently limited treatment options for cognitive decline in Parkinson’s disease.”
While the results in mice are promising, further research is needed to demonstrate the safety and efficacy of PNA5 in humans. The researchers are optimistic about the potential of this drug to address the cognitive aspects of Parkinson’s disease and provide hope for patients in the future.
The findings of this study have been published in Experimental Neurology.