• MicroRNA-23a-3p expression exhibits a dynamic 'V'-shaped change after traumatic brain injury, with early downregulation and subsequent upregulation from day 7.
• Upregulation of MicroRNA-23a-3p significantly reduces mNSS scores and alleviates brain edema and neuronal damage in traumatic brain injury mice.
• Mechanistically, MicroRNA-23a-3p promotes microglial polarization from pro-inflammatory M1 to anti-inflammatory M2 phenotype, reducing pro-inflammatory cytokines and increasing anti-inflammatory factors.
• MicroRNA-23a-3p represents a potential therapeutic target for traumatic brain injury by modulating neuroinflammation and promoting neurological recovery.