Kangxianhuanji formula and its component rutin ameliorate acute exacerbation of idiopathic pulmonary fibrosis by targeting GLUT1 to suppress HIF-1α–mediated glycolysis

Background: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is a life-threatening condition characterized by uncontrolled inflammation and progressive fibrosis, with limited effective therapies. Kangxianhuanji Formula (KHF), a traditional herbal prescription, has been used clinically for AE-IPF, but its molecular mechanisms remain unclear. This study aimed to elucidate the pharmacological mechanisms and active constituents of KHF. Methods: . Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and molecular docking were used for compound-target analysis, and mechanistic validation was performed in macrophages using the glucose transporter 1 (GLUT1, encoded by SLC2A1) inhibitor STF-31 and cellular thermal shift assay (CETSA). Results: KHF markedly alleviated lung injury in AE-IPF mice, as shown by reduced collagen deposition, decreased levels of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and high mobility group box 1 (HMGB1), and suppression of abnormal proliferation of alveolar type II epithelial cells. Network pharmacology suggested involvement of glycolysis-related pathways, including PI3K-Akt and HIF-1α signaling. DARTS and proteomics consistently identified GLUT1 as a core target. KHF inhibited glycolytic reprogramming, reflected by reduced expression of GLUT1, HIF-1α, and hexokinase 2 (HK2), along with decreased lactate production. LC-MS/MS and molecular docking identified rutin as a key GLUT1-targeting compound, which was further confirmed by CETSA. In macrophages, rutin showed anti-inflammatory and anti-glycolytic effects, and co-treatment with STF-31 showed no additive effects, suggesting a GLUT1-dependent mechanism. Conclusion: KHF exerts anti-inflammatory and anti-fibrotic effects in AE-IPF, partly by modulating GLUT1-mediated glycolysis and regulating the GLUT1/HIF-1α axis, with rutin as a key bioactive component. These findings support the clinical application of KHF and highlight GLUT1-centered metabolic pathways as potential therapeutic targets.