Inflammatory bowel disease (IBD) is an incurable disease of the gastrointestinal tract with a lack of effective therapeutic strategies. The proinflammatory microenvironment plays a significant role in both amplifying and sustaining inflammation during IBD progression. Herein, biocompatible drug-free ceria nanoparticles (CeNP-PEG) with regenerable scavenging activities against multiple reactive oxygen species (ROS) were developed. CeNP-PEG exerted therapeutic effect in dextran sulfate sodium (DSS)-induced colitis murine model, evidenced by corrected the disease activity index, restrained colon length shortening, improved intestinal permeability and restored the colonic epithelium disruption. CeNP-PEG ameliorated the proinflammatory microenvironment by persistently scavenging ROS, down-regulating the levels of multiple proinflammatory cytokines, restraining the proinflammatory profile of macrophages and Th1/Th17 response. The underlying mechanism may involve restraining the co-activation of NF-κB and JAK2/STAT3 pathways. In summary, this work demonstrates an effective strategy for IBD treatment by ameliorating the self-perpetuating proinflammatory microenvironment, which offers a new avenue in the treatment of inflammation-related diseases. Graphical Abstract

Although inflammatory bowel disease (IBD) has been extensively studied, the pathogenesis is still not completely understood. As a result, the treatment options remain unsatisfactory and nonspecific. With the rapid advancement of diagnostic imaging techniques, imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) are playing a more important role in IBD diagnosis and evaluation. Recent developments in nanotechnology utilize an interdisciplinary approach to specifically target molecular or cellular IBD pathological process thereby generating nanoparticles (NPs) with high specificity and diagnostic and/or therapeutic efficacy. Nano-based imaging, which incorporates nanotechnology and imaging modalities, may allow for the early detection of IBD, the monitoring of disease activity, and may be used to monitor the therapeutic response at cellular and/or molecular level. In this review, we highlight issues related to nano-based imaging and its application in IBD field.

Among the three anti-VEGF agents used in clinical practice, bevacizumab demonstrated the longest intravitreal retention time and aflibercept the shortest. Significantly higher and prolonged levels of bevacizumab were found in the serum as well as in the heart, liver, and distal bones. These differences may be considered by clinicians when formulating treatment algorithms for intravitreal therapies with these agents.

Systemic opioids led to an inferior quality fusion mass with delay in maturation and remodeling at 6 weeks in this rabbit spinal fusion model. These preliminary results lay the foundation for further research to investigate underlying cellular mechanisms, the temporal fusion process, and the dose-duration relationship of opioids responsible for our findings.