抄録
Microglia phagocytotic activity is vital for homeostasis of the brain by clearing waste, debris, and insoluble aggregates of amyloid β (Aβ) and other proteins. Genetic predisposition is an important factor in the etiology of Alzheimer’s disease (AD), with mutations in genes regulating microglia function and phagocytosis strongly associated with AD risk. However, factors such as lifestyle (e.g., smoking), systemic processes (e.g., glycative and oxidative stresses), and dysbiosis of the intestinal and oral microbiomes have also been implicated in the pathogenesis of neurodegenerative diseases. Mesenchymal stem cell secretome has shown promise as a treatment to improve microglia phagocytosis and cognitive function, while conversely pathogenic bacterial molecular patterns (putatively transmitted by extracellular vesicles [EVs]) are suspected to promote neurodegeneration. In this study, we used our recently developed Aβ phagocytosis model to examine the effects of EVs from probiotic microorganisms on phagocytotic capacity of BV2 microglia. Among the bacterial and yeast strains tested, EVs from Bacillus coagulans lilac-01 and Escherichia coli DH5α both induced a substantial increase in Aβ uptake in a dose dependent manner. As EVs are capable of crossing the blood brain barrier and directly interact with microglia, probiotic EVs have great potential as a treatment for improving microglia functioning in AD and other neurodegenerative diseases.
