Preclinical studies have demonstrated that peripheral LPS induces microglial reactivity and accelerates dopaminergic cell loss across various PD models while TLR4 inhibition reduces microglial proinflammatory activity and neurodegeneration (García-Domínguez et al., 2018; Perez-Pardo et al., 2019; Xie et al., 2023; Zhang et al., 2022). This evidence concerns the gene TLR4 and Parkinson disease.