MCU knockdown mitigates post-stroke neuroinflammation through SLC33A1-mediated reduction of NR4A1 acetylation.

Post-stroke neuroinflammation remains a critical contributor to disease progression and recovery. Building on our prior finding that knockdown of the mitochondrial calcium uniporter (MCU) confers protection against ischemic injury, and guided by transcriptomic evidence implicating NR4A1. We investigated the underlying mechanism using a mouse middle cerebral artery occlusion model and a microglial oxygen-glucose deprivation/reoxygenation model, coupled with protein interaction and acetylation assays. MCU knockdown significantly reduced infarct volume, improved neurological scores, and suppressed microglial cytokine expression. Mechanistically, MCU did not directly interact with NR4A1 under our conditions; immunoprecipitation-mass spectrometry identified SLC33A1 as a novel MCU interactor. Reduced MCU levels led to decreased SLC33A1 expression, diminished NR4A1 acetylation, and attenuated inflammatory outputs, whereas elevating global acetylation blunted these effects. Collectively, our findings demonstrate that MCU knockdown mitigates cerebral infarction and suppresses microglial inflammation via SLC33A1-dependent control of NR4A1 acetylation, supporting MCU knockdown as a promising strategy for post-stroke anti-inflammatory intervention.