1-deoxysphinganine promoted microglial glycolytic reprogramming and neuroinflammation in alzheimer's disease.

Recent evidence suggests that microglial activation, driven by a metabolic shift towards glycolysis, was involved in the pathogenesis of Alzheimer's disease (AD). Although sphingolipid (SL) dysregulation has been linked to AD, the role of 1-deoxysphinganine (deoxySO), an atypical and neurotoxic SL, on microglial glycolytic reprogramming remains unclear. We measured serum deoxySO levels in AD patients and evaluated their association with cognitive performance. In APP/PS1 mice, we examined cerebral deoxySO level and the effects of deoxySO supplementation on cognitive function, neuropathology, and microglial activation. In vitro, BV2 microglia were used to assess inflammatory and metabolic changes via qPCR, western blot, ELISA, and RNA-seq analyses. The serum deoxySO levels were significantly elevated in AD patients, which was positively correlated with cognitive impairment. APP/PS1 mice exhibited increased cerebral deoxySO level, and supplementation with deoxySO could exacerbate cognitive deficits and Aβ plaque accumulation. Moreover, deoxySO supplementation increased microglial activation and enhanced inflammation in vivo and in vitro AD models. qPCR analysis identified disease-associated microglia (DAM) as a key deoxySO-responsive subpopulation, while RNA-seq revealed significant enrichment of genes related to glycolytic metabolism and inflammatory responses. Subsequently, qPCR confirmed that deoxySO promoted glycolytic metabolic reprogramming, which promoted DAM activation, thereby aggravating AD pathology. These findings identify deoxySO as a critical metabolic driver that links to microglial glycolytic activation and neuroinflammation, suggesting that targeting deoxySO-mediated metabolic pathways may offer a novel therapeutic strategy for AD.