Fluoxetine suppresses inflammatory reaction in microglia under OGD/R challenge via modulation of NF-κB signalling.

We aimed to investigate the anti-inflammatory role of fluoxetine, a selective serotonin re-uptake inhibitor, in microglia (MG) and the mechanisms under oxygen glucose deprivation/reoxygenation (OGD/R). An OGD/R model on BV-2 cells was used for the study of microglia under ischemia/reperfusion injury in ischemic stroke. Lentiviral transfection was applied to knock down I kappa B-alpha. Enzyme-linked immunosorbent assay (ELISA) was used for detecting levels of TNF-alpha, IL-1 beta, and IL-6, and real-time PCR was used to assess the expression of I kappa B-alpha protein. Western blotting was applied to analyze NF-kappa B-signaling related proteins and Cell Counting Kit-8 (CCK-8) was used for assessing cell viability. Molecular docking and drug affinity responsive target stability (DARTS) assay were used for the detection of the interaction between I kappa B-alpha and fluoxetine. We found that fluoxetine decreased the levels of TNF-alpha, IL-1 beta, and IL-6 in supernatant as well as NF-kappa B subunits p65 and p50 in BV-2 cells under OGD/R. Fluoxetine significantly increased the level of I kappa B-alpha through the inhibition of I kappa B-alpha ubiquitylation and promoted the bonding of I kappa B-alpha and fluoxetine in BV-2 cells under OGD/R. Knocking down I kappa B-alpha attenuated the decreasing effect of TNF-alpha, IL-1 beta , and IL-6 as well as p65 and p50 in BV-2 cells under OGD/R led to by fluoxetine. In conclusion, our present study demonstrated the anti-inflammatory role of fluoxetine and its mechanisms related to the modulation of NF-kappa B-related signaling in MG under ischemia/reperfusion challenge.