Abstract:Surface topography has a profound effect on the development of the nervous system, such as neuronal differentiation and morphogenesis. While the interaction of neurons and the surface topography of their local environment is well characterized, the neuron–topography interaction during the regeneration process remains largely unknown. To address this question, an anisotropic surface topography resembling linear grooves made from poly(ethylene‐vinyl acetate) (EVA), a soft and biocompatible polymer, using nanoimp… Show more
“…PDMS serves as a negative mold after polymer casting and curing in micromolding and microtransfering. Some studies also used nanoimprinting lithography to prepare grooves in nano size to direct axon growth [ 102 ]. Fig.…”
Section: Anisotropic Surface Patternsmentioning
confidence: 99%
“…During peripheral nerve regeneration, axons need to navigate to reach the distal segment, where Wallerian degeneration occurs. To match the diameter of axons (0.05–1.25 μm) without myelinating cells under injured conditions, Huang et al used nanoimprinting to engineer parallel grooves on a poly (ethylene-co-vinyl acetate) (PEVA) copolymer surface [ 102 ]. Both peripheral neurons from DRG and cortical neurons survived and aligned within the grooves.…”
The treatment of long-gap (>10 mm) peripheral nerve injury (PNI) and spinal cord injury (SCI) remains a continuous challenge due to limited native tissue regeneration capabilities. The current clinical strategy of using autografts for PNI suffers from a source shortage, while the pharmacological treatment for SCI presents dissatisfactory results. Tissue engineering, as an alternative, is a promising approach for regenerating peripheral nerves and spinal cords. Through providing a beneficial environment, a scaffold is the primary element in tissue engineering. In particular, scaffolds with anisotropic structures resembling the native extracellular matrix (ECM) can effectively guide neural outgrowth and reconnection. In this review, the anatomy of peripheral nerves and spinal cords, as well as current clinical treatments for PNI and SCI, is first summarized. An overview of the critical components in peripheral nerve and spinal cord tissue engineering and the current status of regeneration approaches are also discussed. Recent advances in the fabrication of anisotropic surface patterns, aligned fibrous substrates, and 3D hydrogel scaffolds, as well as their
in vitro
and
in vivo
effects are highlighted. Finally, we summarize potential mechanisms underlying the anisotropic architectures in orienting axonal and glial cell growth, along with their challenges and prospects.
“…PDMS serves as a negative mold after polymer casting and curing in micromolding and microtransfering. Some studies also used nanoimprinting lithography to prepare grooves in nano size to direct axon growth [ 102 ]. Fig.…”
Section: Anisotropic Surface Patternsmentioning
confidence: 99%
“…During peripheral nerve regeneration, axons need to navigate to reach the distal segment, where Wallerian degeneration occurs. To match the diameter of axons (0.05–1.25 μm) without myelinating cells under injured conditions, Huang et al used nanoimprinting to engineer parallel grooves on a poly (ethylene-co-vinyl acetate) (PEVA) copolymer surface [ 102 ]. Both peripheral neurons from DRG and cortical neurons survived and aligned within the grooves.…”
The treatment of long-gap (>10 mm) peripheral nerve injury (PNI) and spinal cord injury (SCI) remains a continuous challenge due to limited native tissue regeneration capabilities. The current clinical strategy of using autografts for PNI suffers from a source shortage, while the pharmacological treatment for SCI presents dissatisfactory results. Tissue engineering, as an alternative, is a promising approach for regenerating peripheral nerves and spinal cords. Through providing a beneficial environment, a scaffold is the primary element in tissue engineering. In particular, scaffolds with anisotropic structures resembling the native extracellular matrix (ECM) can effectively guide neural outgrowth and reconnection. In this review, the anatomy of peripheral nerves and spinal cords, as well as current clinical treatments for PNI and SCI, is first summarized. An overview of the critical components in peripheral nerve and spinal cord tissue engineering and the current status of regeneration approaches are also discussed. Recent advances in the fabrication of anisotropic surface patterns, aligned fibrous substrates, and 3D hydrogel scaffolds, as well as their
in vitro
and
in vivo
effects are highlighted. Finally, we summarize potential mechanisms underlying the anisotropic architectures in orienting axonal and glial cell growth, along with their challenges and prospects.
“…This alignment induces cell migration and organization along the nerve on a preferred direction, from the proximal to the distal stump (Huang Y.-A. et al, 2018). With intensive research in this field, it is now known that aligned topographical cues enhanced neurite outgrowth by activating mTOR pathway (Thomson et al, 2017).…”
Section: Tissue Engineering and Regenerative Medicine Concepts For Pnrmentioning
confidence: 99%
“…Huang Y.-A. et al (2018) reported that they were able to exactly place the neuronal cell body and control the direction of axonal growth by merging surface topography and a cell placement device technologies, creating the prospect of engineering complex tissues. Furthermore, they were able to create an on-site axotomy, studying how the topography can influence the initial regeneration of injured axons.…”
Section: Tissue Engineering and Regenerative Medicine Concepts For Pnrmentioning
Peripheral nerve repair and regeneration remains among the greatest challenges in tissue engineering and regenerative medicine. Even though peripheral nerve injuries (PNIs) are capable of some degree of regeneration, frail recovery is seen even when the best microsurgical technique is applied. PNIs are known to be very incapacitating for the patient, due to the deprivation of motor and sensory abilities. Since there is no optimal solution for tackling this problem up to this day, the evolution in the field is constant, with innovative designs of advanced nerve guidance conduits (NGCs) being reported every day. As a basic concept, a NGC should act as a physical barrier from the external environment, concomitantly acting as physical guidance for the regenerative axons across the gap lesion. NGCs should also be able to retain the naturally released nerve growth factors secreted by the damaged nerve stumps, as well as reducing the invasion of scar tissue-forming fibroblasts to the injury site. Based on the neurobiological knowledge related to the events that succeed after a nerve injury, neuronal subsistence is subjected to the existence of an ideal environment of growth factors, hormones, cytokines, and extracellular matrix (ECM) factors. Therefore, it is known that multifunctional NGCs fabricated through combinatorial approaches are needed to improve the functional and clinical outcomes after PNIs. The present work overviews the current reports dealing with the several features that can be used to improve peripheral nerve regeneration (PNR), ranging from the simple use of hollow NGCs to tissue engineered intraluminal fillers, or to even more advanced strategies, comprising the molecular and gene therapies as well as cell-based therapies.
“…nanodiamonds (NDs), beads, and others (Brunetti et al, 2010;Cyster et al, 2004;Edgington et al, 2013;Huang et al, 2014;Kang et al, 2012b;Kang et al, 2014;Khan et al, 2005;Thalhammer et al, 2010)], anisotropic pattern [e.g. ridges, grooves, gratings, and electrospun fibers (Baranes et al, 2012;Clark et al, 1991;Huang et al, 2018;Johansson et al, 2006;Kang et al, 2012a;Kang et al, 2011;Nagata et al, 1993;Nikkhah et al, 2012;Patel et al, 2007;Rajnicek and McCaig, 1997;Schnell et al, 2007;Tonazzini et al, 2014;Webb et al, 1995;Xie et al, 2009;Yang et al, 2005)], and isotropic pattern [e.g. pillars, nanotubes, and columns (Dowell-Mesfin et al, 2004;Hanson et al, 2009;Hu et al, 2004;Mattson et al, 2000;Park et al, 2016;Roberts et al, 2014;Xie et al, 2010)].…”
It has been well studied that the surface topography affects the growth and development of neurons. However, the precise mechanism that the surface topography leads to cellular changes remains unknown. In this study, we created an anisotropic surface using nanodiamonds and discovered this surface topography accelerates the development of primary neurons from both the central and peripheral nervous systems. Using RNA sequencing technology, a previously uncharacterized microRNA (miR6236) was found to exhibit significant and the most substantial decrease when neurons are cultured on this nanodiamond surface. Gain- and loss-of-function assays confirm that miR6236 is the predominant molecule responsible for converting the surface topography into biological responses. We further demonstrate that the depletion of miR6236 can enhance neuroregeneration on inhibitory substrate, uncovering its therapeutic potential for promoting central nervous system regeneration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
