Design and development of minocycline-loaded, thermally responsive polymeric nanoparticles for targeted delivery to activated microglia/macrophages in spinal cord injury model: A novel therapeutic strategy

Functional motor recovery in spinal cord injury (SCI) is a highly challenging field in biomedical treatment. Minocycline is an effective drug agent for microtubule inhibition and neurite outgrowth of cultured neurons in SCI treatment. In the present report, a facile drug delivery system was designed using a chitosan-assisted thermoresponsive polymer to provide sustained release of minocycline from the copolymeric matrix. Additionally, curcumin nanoparticles encapsulated with a copolymeric matrix have been shown to stimulate anti-inflammatory, functional recovery, and effective neuroprotective effects. The distribution of curcumin nanoparticles into a copolymer drug carrier system with thermo-responsive abilities improved sustained delivery, blood bioavailability, stability, and biocompatibility. These results demonstrated that minocycline-loaded Cur-CS/PNIPAM provides enhanced neuroprotection, axonal growth efficiency, and potentially facilitates functional recovery at the site of SCI injury. Therefore, our data offer a facile combination therapeutic strategy for the treatment and recovery of SCI in humans.