Qingzhu granule mitigates acute gouty arthritis through HIF-1α-dependent glycolytic metabolic reprogramming of M1 macrophages.

Background: Acute gouty arthritis (AGA) is an acute inflammatory disorder triggered by the deposition of monosodium urate crystals (MSU) in the joints, clinically characterized by severe pain and transient limitation of joint mobility. Without proper intervention, recurrent episodes can lead to irreversible joint deformities, posing a serious threat to the health of patients. Qingzhu granule (QZG), a traditional Chinese medicinal formula, has been clinically applied in the management of AGA, yet its underlying anti-inflammatory mechanisms remain poorly understood. Aim of the study: This study aims to investigate the therapeutic effects of QZG on MSU-induced AGA and to elucidate its underlying anti-inflammatory mechanisms. Methods: The AGA mouse model was established via intra-articular MSU injection. Swelling index measurement, histopathological staining and pro-inflammatory factor tests (IL-1β, TNF-α and IL-6) were employed to elucidate the therapeutic effects of QZG on AGA. Bioactive components of QZG were identified using UPLC-Q-TOF-MS analysis, while network pharmacology and bioinformatics approaches were employed to predict its potential targets and pathways. Subsequently, flow cytometry and immunofluorescence were applied to determine the proportion of M1 and M2 macrophages in the ankle joints of AGA mice. MSU-stimulated RAW264.7 cells were used to further verify the direct effect of QZG on M1 macrophage polarization. After detecting the effects of QZG on glycolysis and oxidative phosphorylation in macrophages, the expression of glycolysis-related enzymes was also examined. The potential upstream targets of glycolysis-related genes regulated by QZG were predicted using protein-protein interaction network analysis, random forest algorithm, and ChEA3 database. Finally, HIF-1α overexpression plasmids were utilized to confirm that HIF-1α serves as a key target mediating the regulatory effects of QZG. Results: QZG significantly alleviated ankle swelling, reduced immune cell infiltration, and decreased pro-inflammatory factor levels (IL-1β, TNF-α and IL-6) in MSU-induced AGA mice. UPLC-Q-TOF-MS analysis identified 30 bioactive constituents in QZG. Network pharmacology and bioinformatics analysis suggested that macrophage polarization may be the key pathway for the anti-inflammatory effects of QZG. QZG effectively reduced the proportion of M1 macrophages in ankle joints of AGA mice, which was further validated in MSU-stimulated RAW264.7 cells. Moreover, glycolysis capacity was decreased after QZG intervention in RAW264.7 cells. Meanwhile, QZG suppressed the mRNA and protein expression of glycolysis-related enzymes Conclusion: QZG alleviates MSU-induced local inflammation in AGA by suppressing HIF-1α-dependent glycolysis and M1 macrophage polarization.