Neuroneid

Neuroneid is a term used in neuroscience to describe a small, membrane-bound particle observed in neural tissue, proposed to participate in intercellular signaling. The concept emerged from studies of extracellular vesicles and unconventional messenger systems.

Neuroneids are typically 20–60 nanometers in diameter, spherical or irregular, with a lipid bilayer; their internal composition includes RNA, proteins, and sometimes small metabolites. They can be found in cerebrospinal fluid and in extracellular spaces near synapses.

They are thought to form within neurons by budding from endosomal compartments or through selective exocytosis of vesicles; they can be released and taken up by neighboring cells via endocytosis, fusion with membranes, or receptor-mediated uptake.

They are hypothesized to carry signaling cargo, including RNAs, microRNAs, and proteins that modulate synaptic strength, gene expression, or metabolic state. This would complement synaptic transmission and exosome-mediated communication.

The neuroneid concept is debated; some imaging and sequencing studies report particles consistent with neuroneids, while others question their validity due to limitations in resolution, contamination, or misinterpretation of vesicle populations. Further reproducible work is required to establish existence, origin, and function.

If validated, neuroneids could illuminate mechanisms of synaptic plasticity, aging, and neurodegenerative disease, and might enable novel therapeutic strategies or bioengineered communication systems.