Hollow CeO2 with ROS-Scavenging Activity to Alleviate Colitis in Mice

Excessive production of reactive oxygen species (ROS) to induce high oxidative stress is one of the main causes of colitis; thus, it has been regarded as a therapeutic target for colitis treatment. And the nanomaterial-based therapeutic strategies are effective against colitis. However, the previous elaborately designed materials exhibit limited application due to the uncertain biocompatibility and complicated manufacturing processes.In this study, the highly monodisperse hollow CeO2 nanoparticles (H-CeO2) with uniform morphology were obtained by in situ growing CeO2 on solid silica nanoparticles and subsequently removing the silica core. The H-CeO2 was further modified with PEG, which owned excellent biological stability and biocompatibility. The experimental model of colitis induced by dextran sulfate sodium (DSS) was used to investigate the anti-inflammatory effect of H-CeO2-PEG.The H-CeO2-PEG showed good ROS scavenging efficacy and decreased the levels of proinflammatory cytokines (IL-6, IL-1β, IL-18, and TNF-α) in DSS-induced colitis mice. Furthermore, H-CeO2-PEG inhibited the activation of the MAPK signalling pathway to alleviate colitis.This study reveals the therapeutic effects of CeO2-based nanomedicine toward colitis and elucidates the specific signalling pathway involved, which provides potential alternative therapeutic options for patients with inflammation tissue.