Mulberry biomass-derived nanomedicines mitigate colitis through improved inflamed mucosa accumulation and intestinal microenvironment modulation

Abstract

The therapeutic outcomes of conventional oral medications against ulcerative colitis (UC) are restricted by inefficient drug delivery to the colitis mucosa and weak capacity to modulate the inflammatory microenvironment. Herein, a fluorinated pluronic (FP127) was synthesized and employed to functionalize the surface of mulberry leaf-derived nanoparticles (MLNs) loading with resveratrol nanocrystals (RNs). The obtained FP127@RN-MLNs possessed exosome-like morphologies, desirable particle sizes (around 171.4 nm), and negatively charged surfaces (â 14.8 mV). The introduction of FP127 to RN-MLNs greatly improved their stability in the colon and promoted their mucus infiltration and mucosal penetration capacities due to the unique fluorine effect. These MLNs could efficiently be internalized by colon epithelial cells and macrophages, reconstruct disrupted epithelial barriers, alleviate oxidative stress, provoke macrophage polarization to M2 phenotype, and down-regulate inflammatory responses. Importantly, in vivo studies based on chronic and acute UC mouse models demonstrated that oral administration of chitosan/alginate hydrogel-embedding FP127@RN-MLNs achieved substantially improved therapeutic efficacies compared with nonfluorinated MLNs and a first-line UC drug (dexamethasone), as evidenced by decreased colonic and systemic inflammation, integrated colonic tight junctions, and intestinal microbiota balance. This study brings new insights into the facile construction of a natural, versatile nanoplatform for oral treatment of UC without adverse effects.We are grateful to Dr. J. Sun from University of Oxford for his corrections and improvement of this manuscript. Funding: This study was supported by the National Natural Science Foundation of China (82072060 and 22008201), the Fundamental Research Funds for the Central Universities (SWU-XDPY22006), the Venture & Innovation Support Program for Chongqing Overseas Returnees (2205012980212766), the Natural Science Foundation Project of Chongqing (cstc2020jcyj-msxmX0292), and the Natural Science Foundation Project of Chongqing for Distinguished Young Scholar. Author contributions: W.Y., M.W., X.S., and B.X. designed experiments, supervised the project, and wrote the manuscript draft. W.Y., Y.M., H.X., Z.Z., J.W., C.X., W.S., and E.Z. performed the experiments. R.L.R., S.C.K., M.W., X.S., and B.X. edited and revised the manuscript. All authors have approved the final version of the manuscript. Competing interests: The authors declare that there is no con flict of interest regarding the publication of this article