Oral Metal‐Free Melanin Nanozymes for Natural and Durable Targeted Treatment of Inflammatory Bowel Disease (IBD)

Abstract

Oral antioxidant nanozymes bring great promise for inflammatory bowel disease (IBD) treatment. To efficiently eliminate reactive oxygen species (ROS), various metal‐based nanozymes have been developed for the treatment of IBD but their practical applications are seriously impaired by unstable ROS‐eliminating properties and potential metal ion leakage in the digestive tract. Here, the authors for the first time propose metal‐free melanin nanozymes (MeNPs) with excellent gastrointestinal stability and biocompatibility as a favorable therapy strategy for IBD. Moreover, MeNPs have extremely excellent natural and long‐lasting characteristics of targeting IBD lesions. In view of the dominant role of ROS in IBD, the authors further reveal that oral administration of MeNPs can greatly alleviate the six major pathological features of IBD: oxidative stress, endoplasmic reticulum stress, apoptosis, inflammation, gut barrier disruption, and gut dysbiosis. Overall, this strategy highlights the great clinical application prospects of metal‐free MeNPs via harnessing ROS scavenging at IBD lesions, offering a paradigm for antioxidant nanozyme in IBD or other inflammatory diseases.

2D-nanomaterials for AKI treatment

“…To combat these dangerous diseases, it is essential to develop creative therapeutic strategies. Nanomedicine is an innovative technology for designing and synthesizing various materials with fascinating physicochemical properties at the sub-micron level and exploiting them in the biomedical field ( Liu et al, 2022a ; Zhu et al, 2022 ; Huang et al, 2023b ; Sun et al, 2023 ). Multiple medical fields are already benefiting from the advantages offered by nanotechnology, including disease diagnosis and surveillance, cancer therapy, and regenerative medicine, etc ( van der Meel et al, 2019 ; Yang et al, 2019 ; Xu et al, 2020 ; Liu et al, 2022b ).…”

Natural Targeting Potent ROS‐Eliminating Tungsten‐Based Polyoxometalate Nanodots for Efficient Treatment of Pulmonary Hypertension

“…[38] On the other hand, it was also extensively reported that TWD-based nanodrugs are being used to eliminate ROS for the treatment of acute kidney injury and inflammatory bowel disease. [33,39] The disparity in TWD's behavior is due to their differences in synthesis strategy and surface ligands. The TWDs that generate ROS are either bare or sparsely coated with ligands, making them prone to coordinate with H 2 O 2 and generate ROS via Fenton-like reactions.…”

Antioxidative 0-dimensional nanodrugs overcome obstacles in AKI antioxidant therapy

“…60 Melanin is a biopolymer rich in antioxidant groups and endogenous free radicals. 60,83 Therefore, MMPP exhibited an excellent ROS scavenging effect, eliminating 79.4 AE 4.7% of O 2 À at a low concentration (25 mg mL À1 ), and 68.4 AE 2.5% of OH and 85.2 AE 2.3% of ABTS + at a concentration of 100 mg mL À1 (Fig. 4g-i).…”