by Keyword: Coarse-grained model
Smith, CS, Alvarez, Z, Qiu, RM, Sasselli, IR, Clemons, T, Ortega, JA, Vilela-Picos, M, Wellman, H, Kiskinis, E, Stupp, SI, (2023). Enhanced Neuron Growth and Electrical Activity by a Supramolecular Netrin-1 Mimetic Nanofiber Acs Nano 17, 19887-19902
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.
JTD Keywords: axon growth, axon guidance, cell-migration, colorectal-cancer, dcc, dopaminergic-neurons, force-field, functional recovery, netrin-1, neurite outgrowth, neuronal maturation, neurotrophic factor, neurotrophicfactor mimetic, synapsis, Axon growth, Axons, Cells, cultured, Central nervous system, Coarse-grained model, Nanofibers, Netrin-1, Neurogenesis, Neuronal maturation, Neurons, Neurotrophic factor mimetic, Peptide amphiphile, Synapsis
Alvarez, Z, Ortega, JA, Sato, K, Sasselli, IR, Kolberg-Edelbrock, AN, Qiu, RM, Marshall, KA, Nguyen, TP, Smith, CS, Quinlan, KA, Papakis, V, Syrgiannis, Z, Sather, NA, Musumeci, C, Engel, E, Stupp, SI, Kiskinis, E, (2023). Artificial extracellular matrix scaffolds of mobile molecules enhance maturation of human stem cell-derived neurons Cell Stem Cell 30, 219-238 
Human induced pluripotent stem cell (hiPSC) technologies offer a unique resource for modeling neurological diseases. However, iPSC models are fraught with technical limitations including abnormal aggregation and inefficient maturation of differentiated neurons. These problems are in part due to the absence of synergistic cues of the native extracellular matrix (ECM). We report on the use of three artificial ECMs based on peptide amphiphile (PA) supramolecular nanofibers. All nanofibers display the laminin-derived IKVAV signal on their surface but differ in the nature of their non-bioactive domains. We find that nanofibers with greater intensity of internal supramolecular motion have enhanced bioactivity toward hiPSC-derived motor and cortical neurons. Proteomic, biochemical, and functional assays reveal that highly mobile PA scaffolds caused enhanced β1-integrin pathway activation, reduced aggregation, increased arborization, and matured electrophysiological activity of neurons. Our work highlights the importance of designing biomimetic ECMs to study the development, function, and dysfunction of human neurons.Copyright © 2022 Elsevier Inc. All rights reserved.
JTD Keywords: differentiation, force-field, laminin, migration, nanostructures, peptide amphiphiles, spinal-cord, statistical-model, supramolecular materials, Coarse-grained model, Dynamics, Extracellular matrix, Ikvav, Ipsc-derived neurons, Laminin, Neuronal maturation, Peptide amphiphiles, Supramolecular motion, Supramolecular nanofibers
