Discovery of self-assembled nanoparticles from Rubia cordifolia L. before and after carbonization and mechanistic study on their targeted therapy for ulcerative colitis.

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with limited treatment options. The carbonization of Rubia cordifolia L. traditionally enhances its therapeutic effects, but the mechanism remains unclear.

OBJECTIVE

To investigate whether carbonization induces self‑assembled nanoparticles (PRCL NPs) from Rubia cordifolia and to elucidate their mechanism in UC.

STUDY

DESIGN

Self‑assembled nanoparticles were extracted from raw (RCL NPs) and carbonized (PRCL NPs) Rubia cordifolia. A DSS‑induced acute UC mouse model was used to evaluate efficacy. Transcriptomics, proteomics, Western blot, and ELISA were performed to explore the mechanism.

METHODS

Nanoparticles were characterized by DLS, SEM, FTIR, and stability assays. DSS‑induced colitis mice were orally treated with RCL NPs or PRCL NPs (1.3 and 5.2 g/kg). Inflammatory and pathway markers were assessed.

RESULTS

PRCL NPs exhibited smaller particle size (337.2 nm vs. 947.2 nm) and enhanced stability (zeta potential -15.2 mV). Multi‑omics revealed convergent enrichment of the IL‑17 signaling pathway. PRCL NPs significantly upregulated IL‑17A, IL‑22, p‑STAT3, and p‑C/EBPβ (p < 0.001) and suppressed chemokines CCL5, CXCL5, and CXCL10.

CONCLUSION

Carbonization of Rubia cordifolia spontaneously forms structurally optimized self‑assembled nanoparticles (PRCL NPs) that alleviate UC by modulating the IL‑17A/IL‑22-C/EBPβ-STAT3 axis. This study provides a modern nanoscale interpretation of traditional processing theory.