RESUMEN
In this protocol, we describe how to perform the photo-isomerization of cyclic peptides containing an unsaturated ß-amino acid. This process triggers the formation or disassembly of cyclic peptide nanotubes under appropriate light irradiation. Specifically, we start by describing the solid-phase synthesis of the cyclic peptide component. We also present a technique for performing isomerization studies in solution and how to extend it to microfluidic aqueous droplets. For complete details on the use and execution of this protocol, please refer to Vilela-Picos et al.1.
Asunto(s)
Nanotubos de Péptidos , Péptidos Cíclicos , Péptidos Cíclicos/química , Péptidos Cíclicos/síntesis química , Nanotubos de Péptidos/química , Microfluídica/métodos , Soluciones , Nanotubos/química , Procesos Fotoquímicos , Técnicas Analíticas Microfluídicas/métodos , Técnicas de Síntesis en Fase Sólida/métodos , Luz , IsomerismoRESUMEN
Neurotrophic factors are essential not only for guiding the organization of the developing nervous system but also for supporting the survival and growth of neurons after traumatic injury. In the central nervous system (CNS), inhibitory factors and the formation of a glial scar after injury hinder the functional recovery of neurons, requiring exogenous therapies to promote regeneration. Netrin-1, a neurotrophic factor, can initiate axon guidance, outgrowth, and branching, as well as synaptogenesis, through activation of deleted in colorectal cancer (DCC) receptors. We report here the development of a nanofiber-shaped supramolecular mimetic of netrin-1 with monomers that incorporate a cyclic peptide sequence as the bioactive component. The mimetic structure was found to activate the DCC receptor in primary cortical neurons using low molar ratios of the bioactive comonomer. The supramolecular nanofibers enhanced neurite outgrowth and upregulated maturation as well as pre- and postsynaptic markers over time, resulting in differences in electrical activity similar to neurons treated with the recombinant netrin-1 protein. The results suggest the possibility of using the supramolecular structure as a therapeutic to promote regenerative bioactivity in CNS injuries.