Bioactive hydrogel synergizes neuroprotection, macrophage polarization, and angiogenesis to improve repair of traumatic brain injury

Traumatic brain injury (TBI) can lead to severe neurotrauma, leading to long-term cognitive decline and even death. Massive neuronal loss and excessive neuroinflammation are critical issues in the treatment of secondary TBI. To tackle these challenges, we developed a GelMA and CSMA hydrogel loaded with Erythropoietin (EPO) and Interleukin-4 (IL-4), named GC/I/E. By directly loading the hydrogel with EPO, rapid neuroprotection and angiogenesis were achieved. Meanwhile, by loading Mesoporous silica nanoparticles (MSNs) with IL-4 (MSN@IL-4), sustained inflammation modulation during inflammation was attained.