The roles of M2 and M1 polarization of microglia in neuroinflammation are antagonistic: M2 phenotype microglial cells exert anti-inflammatory and neuroprotective effects by secreting transforming growth factor β (TGF-β) and interleukin-10 (IL-10), while M1 polarization produces pro-inflammatory cytokines such as interleukin-1β (IL-1 β), IL-6 and tumor necrosis factor α (TNF-α), which contribute to the disruption of BBB and the deterioration of brain injury 3, 12, 13. This evidence concerns the gene TNF and injury.