Mume Fructus (Prunus mume Sieb. et Zucc.) extract accelerates colonic mucosal healing of mice with colitis induced by dextran sulfate sodium through potentiation of cPLA2-mediated lysophosphatidylcholine synthesis

Mume Fructus (MF) is the fruit of Prunus mume Sieb. et Zucc, a plant of Rosaceae family. Previous studies demonstrated that MF was capable of ameliorating ulcerative colitis (UC) in mice, its action mechanism needs to be clarified.This study deciphered whether and how MF extract accelerates colonic mucosal healing, the therapeutic endpoint of UC.Biochemical, histopathological and qRT-PCR analyses were utilized to define the therapeutic efficacy of MF on dextran sulfate sodium (DSS)-induced colitis in mice. UHPLC-QTOF-MS/MS-based metabolomics technique was adopted to explore the changes of endogenous metabolites associated with UC and responses to MF intervention. qRT-PCR analysis was performed to confirm the molecular pathway in vivo. The effects of MF and lysophosphatidylcholine (LPC) on cell viability, wound healing, proliferation, and migration were examined through a series of in vitro experiments. Moreover, the effects of different subtypes of phospholipase A2 (PLA2) inhibitors on MF-treated colonic epithelial cells were detected by wound healing test and transwell assay.Orally administered MF could alleviate colitis in mice mainly by accelerating the healing of colonic mucosa. Guided by an unbiased metabolomics screen, we identified LPC synthesis as a major modifying pathway in colitis mice after MF treatment. Notably, MF facilitated the synthesis of LPC by enhancing the expression of PLA2 in colitis mice. Mechanistically, MF and LPC accelerated wound closure by promoting cell migration. Moreover, the promotion of MF on wound healing and migration of colonic epithelial cells was blunted by a cytosolic phospholipase A2 (cPLA2) inhibitor.MF can facilitate colonic mucosal healing of mice with colitis through cPLA2-mediated intestinal LPC synthesis, which may become a novel therapeutic agent of UC.