The neuroprotective role of Fructus Broussonetiae in a model of chronic cerebral hypoperfusion with cognitive decline was focused on neural plasticity and microglia/macrophage polarization.Chronic cerebral hypoperfusion was induced by bilateral common carotid artery ligation.Fructus Broussonetiae shortened DESK escape latency and added the number of platform crossings of rats, up-regulated the expression of synaptophysin in the gray matter and increased myelin basic protein expression in the white matter.Further mechanistic experiments were conducted to examine microglia activation and M1/M2 polarization.It was shown that Fructus Broussonetiae reduced the activation of microglia revealed by decreased expression of ionized calcium-binding adapter molecule-1, inhibited M1 polarization of microglia and improved microglial M2 polarization shown by down-regulated the expression stop tool of inducible nitric oxide synthase and Fc fragment of IgG receptor IIIa and up-regulated the expression of arginase-1.
In conclusion, the Chinese herb Fructus Broussonetiae can improve cognitive function following chronic cerebral hypoperfusion by down-regulating the activation of microglia, inhibiting microglial M1 polarization, and improving neural plasticity.