Self-assembling peptide nanofiber hydrogels for central nervous system regeneration

Abstract

Central nervous system (CNS) presents a complex regeneration problem due to the inability of central neurons to regenerate correct axonal and dendritic connections. However, recent advances in developmental neurobiology, cell signaling, cell--matrix interaction, and biomaterials technologies have forced a reconsideration of CNS regeneration potentials from the viewpoint of tissue engineering and regenerative medicine. The applications of a novel tissue regeneration-inducing biomaterial and stem cells are thought to be critical for the mission. The use of peptide nanofiber hydrogels in cell therapy and tissue engineering offers promising perspectives for CNS regeneration. Self-assembling peptide undergo a rapid transformation from liquid to gel upon addition of counterions or pH adjustment, directly integrating with the host tissue. The peptide nanofiber hydrogels have mechanical properties that closely match the native central nervous extracellular matrix, which could enhance axonal growth. Such materials can provide an optimal three dimensional microenvironment for encapsulated cells. These materials can also be tailored with bioactive motifs to modulate the wound environment and enhance regeneration. This review intends to detail the recent status of self-assembling peptide nanofiber hydrogels for CNS regeneration.

Graphical abstract

Keywords

self-assembling peptide / hydrogel / central nervous system (CNS) / nerve regeneration

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 51303119 and 51203108), Natural Science Foundation of Jiangsu Province (BK20130309, BK201341421, BK2011355), Natural Science Foundation of the Jiangsu Higher Education Institutions (13KJB430019), National Science Foundation for Post-doctoral Scientists of China (2013M541724 and 2014T70545), Tsinghua University Initiative Scientific Research Program (20121087982), and 973 Program (2011CB606205).

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2015 Higher Education Press and Springer-Verlag Berlin Heidelberg