Gleditsia sinensis perisperm ameliorates DSS-induced ulcerative colitis via the TLR4/NF-κB/NLRP3 signaling pathway: Safety evaluation and bioactive amino acid profiling.

ETHNOPHARMACOLOGICAL RELEVANCE: Seeds of Gleditsia sinensis Lam. (Zaojiaozi) are traditionally used for intestinal wind hematochezia, dysentery and tenesmus, matching ulcerative colitis (UC) symptoms. Its processed perisperm product Zaojiao Mi (ZJM) may have similar anti-UC effects, yet this remains unclarified.

AIM OF THE STUDY: UC is a chronic intestinal inflammation linked to immune dysregulation. While Zaojiaozi is used for UC, the anti-UC activity, active components, safety and mechanism of ZJM are unclear. This study systematically explored these aspects for its development and application.

MATERIALS AND

METHODS

Amino acid contents in ZJM were quantified and in vivo safety assessed. Enzyme-Linked Immunosorbent Assay (ELISA), Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and relevant assays were used to measure inflammatory factors (IL-6, IL-1β, TNF-α), gene expressions (TLR4, NF-κB p65, NLRP3, Caspase-1) and SCFA levels, together with their correlation analysis.

RESULTS

This study identified 17 amino acids in ZJM. ZJM showed high oral safety with LD50 > 1.35 g/kg, and negative results in Ames, micronucleus, sperm abnormality and teratogenicity tests,it reduced fetal weight and length in a dose-dependent manner, while all developmental parameters remained within normal ranges without obvious pathological or functional abnormalities. Pharmacodynamic study results indicated that ZJM alleviated UC in mice by lowering the corresponding disease activity index, restoring colon length, and mitigating mucosal damage, downregulating IL-6, IL-1β, and TNF-α, inhibiting the TLR4/NF-κB/NLRP3 pathway, while boosting SCFAs (butyrate/propionate negatively correlated with targets). Eleven amino acids (e.g., arginine) exhibited high affinity for pathway targets and correlated with UC targets.

CONCLUSIONS

ZJM is safe and exerts anti-UC effects through anti-inflammation and pathway regulation. Eleven amino acids are potential active components, supporting its use in UC adjuvant intervention.