Sigma-2 receptor complex

Class

Sigma-2 receptor complex antagonist

The sigma-2 receptor complex is a membrane-associated protein assembly, now identified with the gene product TMEM97, found mainly in the endoplasmic reticulum and endolysosomal membranes of neurons and other cells. It participates in cellular cholesterol trafficking and interacts with partner proteins involved in lipid handling and receptor-mediated uptake into the cell. In the central nervous system, the complex has drawn interest because it appears to mediate some of the toxic effects of soluble amyloid-beta oligomers, small misfolded protein aggregates implicated in Alzheimer's disease, at synapses. Compounds that block this site are studied with two broad rationales: interrupting oligomer-triggered synaptic dysfunction to help preserve cognitive function, and, in psychiatric contexts, influencing receptor signaling relevant to negative symptoms of schizophrenia such as blunted emotional expression and social withdrawal, symptom domains poorly served by conventional antipsychotics acting mainly on dopamine receptors. Because the sigma-2 receptor complex sits at the crossing point of lipid metabolism and neuronal signaling, modulating it is relevant wherever synaptic integrity or intracellular trafficking is disrupted, a rationale spanning neurodegenerative and neuropsychiatric disease rather than a single narrow indication.