Investigation of Pharmacological Mechanisms and Active Ingredients of Cichorium intybus L. in Alleviating Renal Urate Deposition via lncRNA H19/miR-21-3p Regulation to Enhance ABCG2 Expression

Renal urate deposition is a pathological inflammatory condition characterized by the accumulation of urate crystals in the kidneys, resulting from uric acid supersaturation. Cichorium intybus L. (chicory) is a traditional medicinal herb recognized for its efficacy in treating hyperuricemia and gout; however, its effectiveness and underlying mechanisms in mitigating renal urate deposition remain inadequately understood. This study investigates the role of the ATP-binding cassette sub-family G member 2 (ABCG2) transporter and the lncRNA H19/miR-21-3p in renal urate deposition, while also validating the therapeutic effects and mechanisms of chicory extract. Renal urate deposition was induced in rats through the administration of potassium oxonate, adenine, yeast extract, and lipopolysaccharide. The levels of serum uric acid (SUA), urate deposition, inflammation, renal function, and histological changes were analyzed. Dual-luciferase assays, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and immunohistochemistry were utilized to elucidate the relationship among ABCG2, lncRNA H19, and miR-21-3p. The chemical composition and active ingredients of chicory were analyzed using UPLC-LTQ-Orbitrap-MS, along with molecular docking and cell experiments. In rats with renal urate deposition, serum UA levels were elevated, renal UA excretion was reduced, and levels of low inflammatory factors, such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and hypersensitivity C-reactive protein (hs-CRP), were increased. Additionally, significant renal tissue damage accompanied the urate deposition. Notably, these abnormalities were substantially reversed following treatment with chicory extract. A dual-luciferase reporter assay confirmed the regulatory relationships among miR-21-3p, lncRNA H19, and ABCG2. Immunohistochemical analysis and RT-qPCR demonstrated a significant upregulation of miR-21-3p expression, alongside a downregulation of lncRNA H19, ABCG2 mRNA, and ABCG2 expression in the kidney tissue of rats with renal urate deposition. Chicory extract may exert its inhibitory effect on renal urate deposition by regulating the lncRNA H19/miR-21-3p axis to enhance ABCG2 expression. Furthermore, UPLC-LTQ-Orbitrap-MS identified 69 components in the chicory extract, including scopoletin, quercetin-3-O-β-D-glucuronide, 11β,13-dihydrolactucopicrin, and kaempferol-3-O-β-D-glucuronide, which were absorbed into the blood of both normal rats and those with renal urate deposition. Molecular docking and cell experiment further validated the effective regulation of 11β,13-dihydrolactucopicrin in ABCG2 and the lncRNA H19/miR-21-3p axis. The downregulation of ABCG2, mediated by the lncRNA H19/miR-21-3p axis, may represent a critical pathogenic mechanism in renal urate deposition. Chicory alleviates this deposition by modulating the lncRNA H19/miR-21-3p axis to enhance ABCG2 expression, potentially through its component, 11β,13-dihydrolactucopicrin, thereby revealing novel therapeutic insights for renal urate deposition.