EXPRESS: Znhit1 alleviates nitroglycerin-induced hyperalgesia in migraine mice via the inhibition of NOD-like receptor signaling pathway

Purpose: Migraine is a neurological disorder, affecting approximately 1.16 billion individuals globally. Zinc finger HIT-type containing 1 (Znhit1), a chromatin remodeler, has exhibited a neuroprotective role. This study aims to investigate the role of Znhit1 in migraine. Methods: A migraine mouse model was established by repeated intraperitoneal injection of nitroglycerin (NTG). The Znhit1 expression in trigeminal nucleus caudalis (TNC) was detected using reverse transcription quantitative polymerase chain reaction and western blot assays. Behavioral phenotype caused by central sensitization was assessed by Von Frey monofilaments and hot plate assays. Inflammatory response was evaluated through enzyme-linked immunosorbent assay and western blot analysis. Gene set enrichment analysis, western blot, cell counting kit-8 (CCK-8), and flow cytometry were utilized to explore potential molecular mechanisms in vitro. Results: Repeated injection of NTG reduced Znhit1 expression in the TNC. Overexpression of Znhit1 alleviated hyperalgesia, upregulated 5-hydroxytryptamine (5-HT) level, and inhibited FBJ osteosarcoma oncogene (c-Fos) and calcitonin gene-related peptide (CGRP) expression. Moreover, overexpression of Znhit1 downregulated the expression of inflammatory markers [interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS)] and inhibited the activation of NOD-like receptor protein 3 (NLRP3) inflammasome. CCK-8 assay found that cell viability was enhanced in lipopolysaccharide (LPS)-induced BV2 cells treated with Znhit1 overexpression, while silencing of Znhit1 resulted in decreased cell viability. In LPS-induced BV2 cells, silencing of Znhit1 enhanced inflammatory response, promoted cell apoptosis, and activated NLRP3 inflammasome, whereas MCC950, a specific inhibitor of NLRP3, reversed these effects induced by silencing of Znhit1. Conclusion: Our results demonstrated that Znhit1 ameliorated hyperalgesia and inhibited inflammatory response by suppressing the activation of NLRP3 inflammasome.