Scientists have devised an innovative strategy for ferrying luminous detectors through the blood-brain barrier (BBB) to track neurotransmitter levels in the brain, a development that could significantly progress Alzheimer’s disease diagnosis and treatment.
Revolutionary Method for Brain Imaging
Neurotransmitter levels in the brain can serve as indicators of brain health and neurodegenerative conditions like Alzheimer’s. Nevertheless, the defensive blood-brain barrier (BBB) complicates the task of delivering luminous detectors capable of detecting these minute molecules to the brain. At present, scientists at ACS Central Science illustrate a technique for packaging these detectors for effortless traversal across the BBB in rodents, facilitating enhanced brain imaging. With further enhancements, this technology could propel advances in Alzheimer’s disease diagnosis and treatment.
It is customary for neurotransmitter levels to diminish with age, yet low adenosine triphosphate (ATP) levels can signal the presence of Alzheimer’s disease. In order to gauge the location and concentration of ATP in the brain, scientists have fashioned luminous detectors from segments of DNA called aptamers that emit light upon binding to a target molecule. While methods for transporting these detectors from the bloodstream to the brain have been devised, most entail artificial constituents that face difficulties in crossing the BBB. To create detectors for live brain imaging, Yi Lu and team encapsulated an ATP aptamer detector in brain-cell-derived minuscule vesicles termed exosomes. They evaluated the novel detector transport system in laboratory models of the BBB and in mouse models of Alzheimer’s disease.
Efficient Detector Delivery Utilizing Exosomes
The BBB laboratory model comprised a stratum of endothelial cells atop a solution housing brain cells. The researchers’ detector-laden exosomes proved nearly four times more proficient than traditional detector delivery frameworks in permeating the endothelial barrier and discharging the luminous detectors into the brain cells. This was corroborated by assessing the noted level of ATP-binding-induced luminescence. Subsequently, Lu’s group administered mouse models of Alzheimer’s disease with either the detector-laden exosomes or unencumbered detectors. Through fluorescence signal measurements in the mice, the researchers determined that the unencumbered detectors predominantly remained in the bloodstream, liver, kidneys, and lungs, whereas detectors dispensed via exosomes accumulated in the brain.
Promising Outcomes in Alzheimer’s Rodent Models
In rodent models of Alzheimer’s disease, the exosome-transferred detectors pinpointed the locality and concentration ofATP levels were observed to be low in distinct brain areas such as the hippocampus, cortex, and subiculum, indicating the presence of the disease. The scientists suggest that their exosome-loaded sensors sensitive to ATP offer potential for non-intrusive real-time brain visualization and could be advanced for the creation of detectors for various clinically significant neurotransmitters.
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