An Electrical Stimulation Device For In Vitro Neural Engineering.

Due to the intrinsically low turnover of neural tissues, regenerative therapies have gained significant interest in the context of degenerative diseases and injury to the central and peripheral nervous systems. Although a range of neuroregenerative strategies involving cell transplants and drugs have been explored, these are often limited by low efficacy and unwanted side effects. Electrical stimulation (ES) is thought to modulate the proliferation and differentiation of neural stem cells (NSCs), and thus it represents a promising strategy for neuroregenerative therapies. However, its influence on the biology of endogenous and exogenous NSCs, and the effect of different stimulation paradigms remains unexplored. Additionally, the variability of stimulation platforms and parameters employed in previous studies prevents reliable and reproducible discoveries. Therefore, there is a need to develop versatile and robust tools to study the effect of electrical stimulation on NSC fate in vitro. This paper outlines the development and functional application of a standardised, electrically stable, and easily reproducible ES platform for in vitro neuroregeneration applications.Clinical Relevance- The elucidation of the cellular and molecular mechanisms underlying the effect of ES paradigms on NSCs proliferation and differentiation holds great potential for the development of neuroregenerative therapies.

Self-Assembling Hydrogel Structures for Neural Tissue Repair.

Hydrogel materials have been employed as biological scaffolds for tissue regeneration across a wide range of applications. Their versatility and biomimetic properties make them an optimal choice for treating the complex and delicate milieu of neural tissue damage. Aside from finely tailored hydrogel properties, which aim to mimic healthy physiological tissue, a minimally invasive delivery method is essential to prevent off-target and surgery-related complications. The specific class of injectable hydrogels termed self-assembling peptides (SAPs), provide an ideal combination of in situ polymerization combined with versatility for biofunctionlization, tunable physicochemical properties, and high cytocompatibility. This review identifies design criteria for neural scaffolds based upon key cellular interactions with the neural extracellular matrix (ECM), with emphasis on aspects that are reproducible in a biomaterial environment. Examples of the most recent SAPs and modification methods are presented, with a focus on biological, mechanical, and topographical cues. Furthermore, SAP electrical properties and methods to provide appropriate electrical and electrochemical cues are widely discussed, in light of the endogenous electrical activity of neural tissue as well as the clinical effectiveness of stimulation treatments. Recent applications of SAP materials in neural repair and electrical stimulation therapies are highlighted, identifying research gaps in the field of hydrogels for neural regeneration.