Background: Sporadic global cognitive decline is on the rise, and current drugs exhibit limited efficacy. Propionate, an SCFAs of the human microbiome, exhibits robust neuroprotective effects.
Methods: We used CCK8 to evaluate neuronal proliferation, DCFH-DA fluorescence probe to quantify ROS production, ELISA to detect IL-1β and IL-6 release, MitoTracker to assess mitochondrial membrane potential, real-time quantitative PCR, and western blotting to analyze DRP1 and anti-Mfn2 protein expression. We also established an in vitro blood-brain barrier model and AD mouse model.
Results: Propionate normalized the mitochondrial membrane potential in glutamate-treated HT22 cells, reversed growth suppression, ROS accumulation, and elevated IL-1 and IL-6 release. Propionate also decreases Drp1 expression and elevates Mfn2 expression via GRP41 receptor binding. In vitro blood-brain barrier models illustrated the potential of propionate to ameliorate glutamate-induced blood-brain barrier damage. In vivo, propionate notably improved the learning and memory capabilities of AD mice and mitigated AD-induced mitochondrial defects.
Conclusion: Supplementation with propionate provides neuroprotection against neurodegenerative diseases. Propionate supplementation may provide a novel strategy for early intervention of neurological disorders.
Keywords: Drp1; Mfn2; Propionate; blood-brain barrier; neural degeneration.