Targeted Scavenging of Reactive Oxygen Species and Alleviating Encephalitis Using Nanozyme-Based Antioxidant Platform

The neurotoxicity of LPS-induced encephalitis stems from the oxidative stress and inflammatory storm it simultaneously triggers. Therefore, developing a synergistic strategy that efficiently enters the brain, eliminates free radicals, and regulates the immune microenvironment is key to therapeutic breakthroughs. To meet this challenge, this study developed a nanoplatform, cerium-doped carbon quantum dots (S2P@Ce-CQDs). This nanoplatform fully leverages the properties of Ce-CQDs, including their ultrasmall size, which enables excellent blood-brain barrier (BBB) penetration, and their inherent fluorescence, which facilitates tracking of treatment. Additionally, Ce doping confers the material dual enzymatic activity, mimicking superoxide dismutase and catalase, to efficiently eliminate excess reactive oxygen species (ROS) in the lesion area. Importantly, the surface-modified S2P targeting peptide specifically recognizes M1 macrophages, guiding S2P@Ce-CQDs to accumulate precisely at the encephalitis lesion. Systematic studies demonstrate that this platform not only effectively reduces oxidative stress damage but also modulates macrophage polarization, thereby reshaping the neuroinflammatory microenvironment. This multifunctional nanoplatform, which integrates targeted delivery, fluorescence imaging, antioxidant, and immune regulation, is expected to improve the problem that drugs are difficult to effectively cross the BBB in the treatment of encephalitis.