Sirtuin 3 promotes microglia migration by upregulating CX3CR1.

We studied the role of Sirtuin 3 (SIRT3) in microglial cell migration in ischemic stroke. We used a middle cerebral artery occlusion (MCAO) model of focal ischemia. We then applied lentivirus-packaged SIRT3 overexpression and knock down in microglial N9 cells to investigate the underlying mechanism driving microglial cell migration. More microglial cells appeared in the ischemic lesion side after MCAO. The levels of SIRT3 were increased in macrophages, the main source of microglia, after ischemia. CX3CR1 levels were increased with SIRT3 overexpression. SIRT3 promoted microglial N9 cells migration by upregulating CX3CR1 in both normal and glucose deprived culture media. These effects were G protein-dependent. Our study for the first time shows that SIRT3 promotes microglia migration by upregulating CX3CR1.