Metal polyphenol network/cerium oxide artificial enzymes therapeutic nanoplatform for MRI/CT-aided intestinal inflammation management

Intestinal inflammation, such as ulcerative colitis (UC), is a condition in which there is chronic or recurring inflammation of the gastrointestinal tract . Designing safe, effective, and multifunctional nanomedicines is one of the current difficulties in the treatment of UC. Here we developed a delivery nanosystem based on metal polyphenol network/cerium oxide artificial enzymes (MPN@CeOx) to manage UC and evaluate the severity of inflammation by MRI/CT imaging. MPN@CeOx was engineered by Fe 3+ and epigallocatechin gallate (EGCG) wrapped around CeOx. Increased levels of oxidative stress in the inflammatory lesion facilitated the release of Fe 3+ and EGCG from MPN and liberated CeOx. EGCG with anti-oxidative and anti-inflammatory effects plus CeOx with superoxide dismutase (SOD)-like activity effectively scavenged reactive oxygen species (ROS) and reduced pro-inflammatory cytokines to protect cells from oxidative damage . In addition, H 2 O 2 -responsive releasing of Fe 3+ at the site of inflammation and Ce elements in CeOx enable MRI/CT imaging of UC. In mice colitis models, oral administration of enteric-coated MPN@CeOx alleviated intestinal inflammation and intestinal barrier dysfunction. RNA sequencing analysis revealed that MPN@CeOx ameliorated UC symptoms mainly through inflammation-related signaling pathways . MPN@CeOx with multilevel inflammation management and multimodal imaging capabilities represents an innovative diagnosis and treatment approach for UC.