Supplementary file 1_Ulcerative colitis therapeutic effects and pharmacokinetics of flexible quercetin nanocrystals prepared with geniposide assistance.docx

Objective<p>This study aimed to improve the oral bioavailability and therapeutic efficacy of quercetin (QUE) against ulcerative colitis (UC) by formulating flexible quercetin nanocrystals (QUE-NCs) with the assistance of geniposide (Gen).</p>Methods<p>QUE-NCs were prepared via an antisolvent precipitation method leveraging the interaction between QUE and Gen. Therapeutic efficacy was evaluated in a dextran sulfate sodium (DSS)-induced UC mouse model using disease activity index (DAI), colon histopathology (H&E), and ELISA-based biochemical assays.

Biosafety was assessed through serum biochemistry, organ indices, and histopathological examination. An HPLC method was developed and validated for quantifying QUE in rat plasma, followed by a pharmacokinetic study in Wistar rats.</p>Results<p>QUE-NCs exhibited a flexible rod-like morphology and significantly alleviated UC symptoms, including weight loss, fecal occult blood, and colonic damage. Treatment with QUE-NCs reduced pro-inflammatory cytokines (TNF-α: 173.51 pg·mL⁻¹; IL-6: 32.55 pg·mL⁻¹), restored anti-inflammatory IL-10 levels (126.37 pg·mL⁻¹), and suppressed oxidative stress markers (MPO: 579.95 pg·mL⁻¹; MDA: 62.44 nmol·g⁻¹; iNOS: 6.78 ng·mL⁻¹).