Bioactive constituents of Mosla chinensis-cv. Jiangxiangru ameliorate inflammation through MAPK signaling pathways and modify intestinal microbiota in DSS-induced colitis mice

Background: Mosla chinensis Maxim. cv. Jiangxiangru (JXR), a traditional Chinese medicine, commonly used for the therapy of cold, fever, diarrhea, digestive disorders, and other diseases. Inflammatory bowel disease (IBD) is a chronic disorder of the human gastrointestinal tract. Research about the effect of JXR on IBD and the active ingredient composition of JXR remains deficiency. Purpose: This study aims to determine the phytochemical composition and the anti-inflammatory property of JXR, as well as the possible anti-inflammatory mechanisms. Methods: The bioactive profile of JXR extracts was determined by UPLC-LTQ-Orbitrap-MS. A DSS induced colitis mouse model was applied to explore the anti-inflammatory activity of JXR. The body weight, colon length and histopathological status of colon tissue were evaluated. The content of inflammatory mediators (nitric oxide (NO), prostaglandin E-2 (PGE(2))) and cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1 beta (IL-1 beta)), corresponding mRNA and protein expression levels were analyzed. Oxidation pressure and gut microbial composition were also explored. Results: Totally 63 constitutes were identified from JXR, among them, phenolic acids and flavonoids comprised a large part, and rosmarinic acid (RA) was the main compound. The results of DSS-induced colitis mice model indicated that JXR effectively ameliorated inflammation, restore the redox balance in the gut. JXR treatment significantly reduced the production of reactive oxygen species (ROS), increased the activity of antioxidative enzyme, suppressed the secretion of inflammatory mediators (NO, PGE(2)) and cytokines (TNF-alpha, IL-6, IL-1 beta). JXR also restrained the activation of mitogen-activated protein kinases (MAPKs) signaling pathway. Furthermore, JXR could restore the microbial diversity by suppressing Bacteroidaceae, increasing Bifidobacteriales and Melainabacteria in DSS colitis mouse model. Conclusions: This study demonstrated that JXR composed with various bioactive compounds, effectively ameliorated colitis, restored the redox balance and regulated gut microbiota. Results from the present study provide an insight of therapeutic potential of JXR in IBD based on its anti-inflammatory and antioxidant properties, also provide a scientific basis for using JXR as a functional ingredient to promote colon health.