🧬 BDNF Extraction Viewer

Neuroinflammation driven by dysfunctional microglial responses represents a critical early pathogenic process, particularly in the context of Alzheimer's disease (AD). The natural flavonoid fisetin possesses anti-inflammatory characteristics; however, the exact mechanisms via which it mitigates microglial dysfunction in AD are not fully elucidated. This work employed a combination of in vivo and in vitro approaches, utilizing male APP/PS1 mice and ADDL-stimulated primary microglia. Behavioral tests, immunohistochemistry, molecular profiling, and mitochondrial function assays were conducted. This research combines network pharmacology, molecular docking, and cellular thermal shift assays (CETSA) to offer predictive insights. Fisetin treatment improved cognitive performance in APP/PS1 mice, concurrently reducing amyloid pathology and plaque-associated microglial clustering. In primary microglia, fisetin potently inhibited ADDL-induced pro-inflammatory activation, mitochondrial ROS overproduction, and membrane depolarization. PI3K was identified as a signaling node potentially involved in fisetin-mediated regulation of microglial inflammatory responses. Accordingly, fisetin constrained microglial inflammatory signaling, at least in part through modulation of the PI3K-Akt-NF-κB axis, thereby limiting NF-κB nuclear translocation and pro-inflammatory cytokine release in both the mouse hippocampus and cultured primary microglia. Furthermore, conditioned medium from fisetin-treated microglia alleviated neuronal damage and restored the expression of BDNF and PSD95 in primary neurons. The collective findings, along with experimental studies utilizing the PI3K inhibitor (LY294002), indicate that PI3K may act as a molecular target of fisetin, underscoring its potential therapeutic significance in regulating early inflammatory processes in AD.