TLR4 and Parkinson disease: Moreover, the neuroprotective effect of butyric acid on PD may be mediated through the Janus kinase-2/signal transducer and activator of tran-ions-3 (JAK2/STAT3) and TLR4/MyD88/NF-kB signaling pathways (Guo et al., 2023; Ji et al., 2023).