NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome mediates inflammation, induces pyroptosis, and regulates periodontal tissue remodeling through the maturation and secretion of its downstream cysteine protease 1 (Caspase-1)-dependent pro-inflammatory cytokines, interleukin (IL)-1β and IL-18. Orthodontic force mediates the aseptic inflammation of periodontal tissues and triggers adaptive alteration of periodontal tissues, thereby promoting the movement and stability of orthodontic teeth. NLRP3 inflammasome plays an important role in orthodontic tooth movement and causes periodontal tissue inflammation and orthodontic inflammatory root resorption in orthodontic patients. Literature review suggests that NLRP3 inflammasome is involved in the activation and differentiation of periodontal ligament fibroblasts, periodontal ligament stem cells, macrophages, osteoblasts, and osteoclasts in orthodontic tooth mobile tissue remodeling. Additionally, it targets the upstream nuclear factor kappa-B signaling pathway; downstream effectors, such as Caspase-1, IL-1β, and IL-18; and the NLRP3 inflammasome components for regulating tooth movement as well as treating and preventing orthodontics-associated periodontitis and orthodontic-induced inflammatory root resorption. Future studies can be focused on the specific mechanism of NLRP3 inflammasome tissue modification during orthodontic tooth movement. This article reviews the effects and regulatory mechanisms of the NLRP3 inflammasome signaling pathway on the corresponding tissue remodeling during orthodontic tooth movement.

Activation of the heart normally begins in the sinoatrial node (SAN). Electrical impulses spontaneously released by SAN pacemaker cells (SANPCs) trigger the contraction of the heart. However, the cellular nature of SANPCs remains controversial. Here, we report that SANPCs exhibit glutamatergic neuron-like properties. By comparing the single-cell transcriptome of SANPCs with that of cells from primary visual cortex in mouse, we found that SANPCs co-clustered with cortical neurons. Tissue and cellular imaging confirmed that SANPCs contained key elements of glutamatergic neurotransmitter system, expressing genes encoding glutamate synthesis pathway (Gls), ionotropic and metabotropic glutamate receptors (Grina, Gria3, Grm1 and Grm5), and glutamate transporters (Slc17a7). SANPCs highly expressed cell markers of glutamatergic neurons (Snap25 and Slc17a7), whereas Gad1, a marker of GABAergic neurons, was negative. Functional studies revealed that inhibition of glutamate receptors or transporters reduced spontaneous pacing frequency of isolated SAN tissues and spontaneous Ca