Application of injectable hydrogels in the central and peripheral nervous system as a unique and flexible platform...

The nervous system, comprising the central and peripheral components, is essential for regulating physiological functions. Damage to neural tissue often results in severe motor and sensory deficits, with limited endogenous regenerative capacity posing major challenges for repair. Tissue engineering offers promising strategies for neural regeneration by integrating cells, biomaterial scaffolds, and drug delivery systems. Among biomaterials, injectable hydrogels have attracted significant attention due to their biocompatibility, biodegradability, flexibility, and ability to undergo minimally invasive in situ gelation. These hydrogels serve as versatile carriers for cells and therapeutic agents, enabling precise delivery to hard-to-reach tissues while promoting neural repair. This review highlights recent advances in the design, preparation, and application of injectable hydrogels for neural tissue engineering. We discuss their roles in regenerating the brain, spinal cord, and peripheral nerves, address current challenges, and provide perspectives on future developments. Collectively, injectable hydrogels represent a promising platform for developing next-generation regenerative therapies aimed at restoring both anatomical structure and functional outcomes in neural tissues.