Redox-active nanoparticles for inflammatory bowel disease

Abstract

Homeostasis of gut microbiota is extremely essential for maintaining nutrient metabolism and regulating immunological function. The increasing evidence suggests that inflammatory bowel disease (IBD) is strongly associated with dysregulation of gut microbiota. During activated inflammation, excessive reactive oxygen species (ROS) and reactive nitrogen species (RNS) produced by inflammatory cells play a detrimental role in regulating IBD and gut microbiota. ROS/RNS cause damage to the surrounding tissues, including nutrient absorption disorders, intestinal dysmotility and barrier dysfunction. Meanwhile, ROS/RNS provide terminal electron receptors for anaerobic respiration and support the bloom of facultative anaerobes, eventually causing gut microbiota dysbiosis. Redox-active nanoparticles (NPs) with catalytic properties or enzyme-like activities can effectively scavenge ROS/RNS, and selectively target inflamed sites via ultrasmall size-mediated enhanced permeation and retention (EPR) effect, showing great potential to regulate IBD and maintain the homeostasis of gut microbiota. In addition, the widespread application of NPs in commercial products has increased their accumulation in healthy organisms, and the biological effects on normal microbiota resulting from long-term exposure of NPs to gastrointestinal tract also need attention.

Phytic acid-modified CeO2 as Ca2+ inhibitor for a security reversal of tumor drug resistance

“…Consistent with the catalase-like results, the SOD-like activity of CePA was higher than that of CeO 2 at each concentration, demonstrating the higher antioxidant activity of CePA over CeO 2 . The ratio of Ce 3+ /Ce 4+ plays a pivotal role in their cpability of ROS scavenging [32,[39][40][41][42]. Herein, X-ray photoelectron spectra (XPS) of CeO 2 and CePA suggested their similar surface Ce 3+ fractions (Fig.…”

“…Therefore, reducing the side effects of Dox on normal cells is also highly expected. Due to high antioxidant capability of CeO 2 nanozyme for the degradation of ROS [36][37][38][39][40][41][42][43], the porous nanoceria (CeO 2 ) was used as an adjuvant medicine to alleviate Dox-induced oxidative stress in normal cells [32]. Therefore, the CePA nanozymes are expected to serve as a highly efficient Ca 2+ nano-inhibitor, reducing Ca 2+ levels in drug-resistant tumor cells, inhibiting P-gp overexpression, and increasing intracellular accumulation of drugs.…”

“…Due to the severe Dox-induced oxidative stress and the high antioxidant ability of nanoceria as nanozyme to scavenge druginduced ROS [32,42], herein, we anticipated that nanocerias would suppress or even prevent adverse effects of Dox on normal organs. Then, the ROS scavenging activity of CeO 2 and CePA was evaluated by calibration from the standard catalase and superoxide dismutase (SOD) assay kits.…”

Recent Progress of Surface Modified Nanomaterials for Scavenging Reactive Oxygen Species in Organism

“…Nanomaterials with multifunctional surface modification have been explored in the treatment of various diseases. By modification of multiple components, the biocompatibility, biosafety, and targeted and antioxidative efficiency of these nanomaterials can be improved. − …”

ROS‐Sensitive Polymer Micelles for Selective Degradation in Primary Human Monocytes from Patients with Active IBD

“…[11][12][13] ROS-sensitive nanoparticles showed their potential in cancer models, [14] and recent studies have used polymer nanoparticles for targeting inflamed intestine in IBD models. [15][16][17][18] However, this promising approach has some limitations and issues in the design and fabrication of appropriate and selective carrier system. [19] The polymers themselves, nanoparticles, and their oxidized products have to be biocompatible [20] and demonstrate noninflammatory properties.…”