An experimental nasal spray has successfully protected nerve cells and preserved memory in mice with Alzheimer's disease, according to a study published in the scientific journal Translational Neurodegeneration.
The experimental treatment relies on extracellular vesicles, microscopic biological bubbles that cells naturally use to transport active biological substances. Researchers harvested these vesicles from the amniotic membrane of the placenta and administered them through the nose to mice affected by a model of Alzheimer's disease.
The intranasally administered particles successfully crossed into the brain and reached the hippocampus, a brain region that plays a central role in memory formation and retention. Intranasal delivery is widely studied as a method to transport therapies directly to brain tissue by bypassing the blood-brain barrier.
Once in the brain, the therapy reduced neuroinflammation, protected existing neurons from destruction, and improved the function of synapses. Synapses are the specialized microscopic junctions through which nerve cells send and receive chemical and electrical signals, making their health essential for normal cognitive communication.
Memory Improvements in Laboratory Tests
As a result of the intervention, the treated animals performed significantly better in behavioral tests designed to evaluate spatial, working, and recognition memory. Spatial memory governs environmental navigation, working memory manages temporary information storage for decision-making, and recognition memory allows the identification of familiar objects or surroundings.
The researchers reported that the therapeutic treatment was effective both in preventing the initial emergence of memory deficits and in reducing cognitive impairments that had already developed. In addition to the animal trials, positive therapeutic effects were observed in laboratory experiments conducted on human neurons.
Alzheimer's disease is a chronic neurodegenerative disorder and the leading cause of dementia worldwide. It is characterized by progressive neuronal damage, synaptic loss, and neuroinflammation within the brain. Over time, the condition impairs memory, language, and independent daily functioning.
The amniotic membrane is the innermost protective lining of the placenta. In medical research, placental tissues are valued for their low immunogenicity and rich concentration of biologically active compounds, while extracellular vesicles serve as natural cellular messengers capable of carrying protective molecules across cellular membranes.
Future Treatment Prospects
The study authors concluded that their results establish a promising new therapeutic strategy for treating Alzheimer's disease by directly targeting neuroinflammation and stabilizing the cellular environment around neurons. However, the researchers emphasized that the approach has only been validated in animal models and laboratory cell cultures, requiring further investigation before human clinical applications can be considered.
The findings add to a growing body of research investigating protective factors against cognitive decline. Previous scientific studies have determined that a genetic or biological disposition toward longer sleep duration is associated with a lower overall risk of developing Alzheimer's disease.
