TLR4 and Parkinson disease: Researchers provide evidence that LPS is a potent inducer for neuroinflammation by activation of astrocyte, microglia-cells, and TLR4, α7 nAChR, LRP-1 receptors, Aβ accumulation, and tau phosphorylation, which leads to neuronal loss, synaptic dysfunction, memory loss, decline in cognitive behaviors results in PD and Alzheimer’s disease.