Codelivery of minocycline hydrochloride and dextran sulfate via bionic liposomes for the treatment of spinal cord injury

After primary injury to the spinal cord, a series of microenvironmental changes can lead to secondary injury. The use of nano-targeted drug delivery systems to improve the postinjury microenvironment, inhibit inflammation and reduce neuronal apoptosis can be of great help during spinal cord injury (SCI) recovery. In this study, we prepared primary macrophage membranes bionic modified nanoliposomes ([email protected]−Lips) loaded with minocycline hydrochloride (MH) and dextran sulfate (DS) to target their delivery to the site of injury to bind calcium ions in situ and form metal ion complexes. Complex formation reduced calcium ion concentrations and calcium-associated neuronal apoptosis, while MH was slowly released to produce better anti-inflammatory effects. The successful preparation of [email protected]−Lips was verified using transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), western blotting and dynamic light scattering (DLS). The targeting capability of the [email protected]−Lips was demonstrated using a Transwell system and an in vivo imaging system. The therapeutic efficacy of [email protected]−Lips was examined in vitro and in vivo using flow cytometry, immunofluorescence, ELISA kits and western blotting. The results showed that SCI mice treated with [email protected]−Lips received high behavioral scores, which led to the conclusion that [email protected]−Lips have great potential for the treatment of SCI.