The activation of proinflammatory M1-type macrophages in the injured lesion accelerates the progression of a spinal cord injury (SCI). However, adverse side effects during systemic treatments targeting M1 macrophages have limited their applications. Nanoplatforms are novel carriers of traditional Chinese medicine because of their great efficiency to deliver and accumulation in the lesion. Herein, we synthesized a modified zeolitic imidazolate framework-8 (ZIF-8) nanoplatform for internalization and accumulation in the injured spinal cord and effective administration for SCI. In vitro and in vivo experiments suggested that Prussian blue and Schisandrin B modified ZIF-8 effectively accumulated in M1 macrophages, inhibited reactive oxygen species (ROS), and polarized the macrophage from proinflammatory M1 to anti-inflammatory M2 for rapid tissue infiltration by reprogramming the metabolic macrophages phenotype. This nanoplatform achieves a synergistic therapeutic effect of immunomodulation and neuroprotection, thereby shedding new light on the application of ZIF-8, and provides great potential for SCI.
Keywords: inflammation; polarization; reactive oxygen species; spinal cord injury; zeolitic imidazolate framework-8.