Preventive strategy against PM2.5‐induced neuronal cell death

Abstract Background Particulate matter 2.5 (PM2.5) can gain access to the lungs and the circulatory system and may sequentially cross the blood brain barrier (BBB). Recent data suggested that these particles reaching the brain may cause neurological disorders including AD and PD. However, there is no study on how to prevent PM2.5‐induced inflammation and neurotoxicity. Objective In this study, we have demonstrated that PM2.5 increases the neuroinflammation and neuronal cell death, and that natural products such as astaxanthin and chlorophyll can prevent the subsequent neurotoxicity, mainly based on its anti‐oxidative and anti‐inflammatory properties. In this study, we have demonstrated that PM2.5 increases the neuroinflammation and neuronal cell death, and that natural products such as astaxanthin and chlorophyll can prevent the subsequent neurotoxicity, mainly based on its anti‐oxidative and anti‐inflammatory properties. Method In this regard, we measured 1) the mRNA expression of inflammatory mediators including iNOS, IL‐1b, and IL‐6, 2) the nitric oxide and reactive oxygen species production, 3) signaling molecules such as MAPKs and PI3K, 4) neurite extension and neuronal cell death using the immunocytochemistry and MTT assay. We used a well‐characterized Diesel particulate matter, PM2.5, from SIGMA‐Aldrich. Result PM2.5 increased inflammatory cytokines such as IL‐6 and IL‐1b production in rat astrocytes and microglia. Natural products including astaxanthin, chlorophyll and olive oil components attenuated PM2.5‐induced increased NO and other inflammatory cytokines expressions and prevented neuronal cell death in rat primary cortical neurons. Conclusion Our results show that PM2.5 activates the glia through inflammation leading to neurotoxicity, and natural products we tested can prevent this through the inhibition of glial activation. These results demonstrate natural products such as astaxanthin, chlorophyll and olive oil components as the candidate against air pollution exposure such as PM2.5.