Multi-omics Analysis Reveals miR-7220-5p Alleviates N₂O Addictive Behaviors via NR2B/ERK/CREB Signaling

Nitrous oxide use disorder (NUD) has recently received increasing social concern for its sharp rise among young people. However, the underlying mechanisms of NUD remain largely unexplored, which obstructs treatment strategy development and may exacerbate the epidemic of N₂O abuse. Thus, specifying the essential mechanisms and targets in NUD are desperately needed. Here we unveiled a series of molecular adaptations regarding N₂O reward memory in nucleus accumbens (NAc) of mice through multi-omics approaches comprising transcriptomics, proteomics, and metabolomics approaches. Our miRNA transcriptomics and pull-down proteomics analyzes uncovered that miR-7220-5p regulated N₂O-induced conditioned-place preference (CPP) and associated increase of dendritic spine density in NAc of male mice. Our pull-down proteomics and metabolomics analyses revealed that miR-7220-5p modulated ERK signaling pathway by directly binding with NR2B receptor. In summary, our work confirmed that restoring miR-7220-5p expression in NAc protected against synaptic abnormality via the NR2B/ERK/CREB signaling, thereby attenuating CPP behaviors in NUD. Selective inhibition of NR2B or ERK signaling blocked the reward memory of N₂O-CPP via NAc microinjection. Our study proposed a potential therapeutic strategy for NUD and provided comprehensive resources of biological data to support future investigations of NUD treatment.