TLR4 and ischemia reperfusion injury: In ischemia-reperfusion injury in the heart, dexmedetomidine activation of α2 adrenoceptors downregulates toll-like receptor 4 (TLR4) expression and then regulates NF-κB (Sun et al., 2020); therefore, α2 adrenoceptors may regulate bace1 through the TLR4-NF-κB signaling pathway, affecting Abeta deposition.