Alleviation of nitroglycerin-induced migraine in rats: inhibition of central sensitization by optimizing Qinggan Jieyu decoction regulation of purinergic receptor P2X ligand-gated ion channel 7 and autophagy.

Abstract

OBJECTIVE: To investigate the effects of optimizing Qinggan Jieyu decoction on purinergic receptor P2X ligand-gated ion channel 7 (P2X7R) and autophagy in migraine model rats based on molecular biology and histopathology. METHODS: A migraine rat model was established by a single subcutaneous nitroglycerin (NTG) injection into the posterior neck. QGJY was administeredgavage for 7 d prior to NTG induction. Behavioral changes, central sensitization biomarkers, and inflammatory cytokine levels were analyzed to evaluate migraine severity. Western blot, immunofluorescence, quantitative real-time PCR, and transmission electron microscopy were employed to assess P2X7R expression and autophagy activity in trigeminal nucleus caudalis (TNC) tissues. The P2X7R agonist 2' (3')-O-(4-Benzoylbenzoyl) adenosine-5'-triphosphate (BzATP) was further utilized to validate QGJY's regulatory effects. RESULTS: QGJY significantly reduced cage-climbing and head-scratching frequencies in NTG-induced migraine rats, downregulated serum and TNC levels of interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha, and suppressed central sensitization markers (substance P; calcitonin gene-related peptide; and c-fos induced growth factor) in TNC tissues (0.05). QGJY markedly decreased microglial cell counts and average immunofluorescence intensity in TNC tissues and promoted elongation of microglial protrusions (0.05). Concurrently, QGJY downregulated P2X7R protein and mRNA expression, reduced the light chain 3 (LC3)-II/LC3-I ratio, elevated ubiquitin-binding protein p62 levels, and diminished autophagosome numbers in TNC tissues (0.05). Furthermore, QGJY reversed BzATP-induced P2X7R upregulation (0.05). CONCLUSIONS: QGJY alleviates migraine and inhibits central sensitization in rats, potentially by downregulating P2X7R expression, concomitantly suppressing autophagy, attenuating microglial activation, and reducing pro-inflammatory cytokine release.