Regulation of inflammation, neurotrophins, glycosylation, sensory nerve innervation and pain in intervertebral disc degeneration using an implantable hyaluronic acid hydrogel

Event Abstract Back to Event Regulation of inflammation, neurotrophins, glycosylation, sensory nerve innervation and pain in intervertebral disc degeneration using an implantable hyaluronic acid hydrogel Isma Liza Mohd Isa1, 2*, Akshay Srivastava1, Michelle Kilcoyne1, 3, Sunny A Abbah1, Oliver Carroll1, David Tiernan1, Peter Owens2, 4, Lokesh Joshi1, 3, Peter Dockery1, 2, 4, David P Finn1, 5 and Abhay Pandit1 1 National University of Ireland, Centre for Research in Medical Devices (CÚRAM), Ireland 2 National University of Ireland, Anatomy, Ireland 3 National University of Ireland, Glycoscience Group, Ireland 4 National University of Ireland, Centre for Microscopy and Imaging, Ireland 5 National University of Ireland, Pharmacology and Therapeutics, Galway Neuroscience Centre and Centre for Pain Research, Ireland Introduction: Symptomatic intervertebral disc (IVD) degeneration is mediated by an inflammation that increases neurotrophin production to sensitize innervation in the disc resulting in pain. High molecular weight hyaluronic acid (HA) hydrogels demonstrate potential as bioactive materials for IVD regeneration as they exert an anti-inflammatory[1], analgesic effect[2] and mimic the disc microenvironment[3]. It is hypothesized that HA hydrogels attenuate the inflammatory receptor and neurotrophins in an in vitro inflammation milieu, and that modulate inflammation, glycan expression and inhibit hyper-innervation associated with pain in an in vivo IVD injury model. Experimental Methods: Sodium hyaluronate 0.75% (w/v) was mixed in 1 ml distilled water with 4-arm PEG-amine 75 mM, N-hydroxysuccinimide (NHS) 15% (w/v) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) 9% (w/v). The spherical-shaped hydrogels were then obtained by pipetting a channel volume of 5 μl onto a hydrophobically modified glass slide. The cytotoxicity of HA hydrogels was tested on nucleus pulposus (NP) cells and the stability under hydrolytic and enzymatic degradation was tested. The effect of HA hydrogels was determined in inflamed NP cells by investigating inflammatory receptor IL-1R1, MyD88, and expression of NGF and BDNF mRNA. Further, all protocols of in vivo studies were pre-approved by the institutional Animal Care Research Ethics Committee (ACREC). Thirty (30) Sprague Dawley rats were randomized into three groups: sham (n=10), injury (n=10) and injury with treatment implantable HA hydrogel (n=10). The injury model was created in the coccygeal IVDs (Co4-Co5 and/or Co5-Co6) using a 1.5 mm diameter biopsy puncture to pierce 2 mm tissue depth. Nocifensive behavior of the rats in response to thermal, cold and mechanical stimuli will be observed at baseline day -1 and post-operative days 1, 7, 14, 28 and 56. The rats were then sacrificed to harvest the IVD and spinal cord for analyses. Pro-inflammatory cytokine IL-1β and molecular pain marker of c-fos, NGF and BDNF were determined by qRT-PCR. Immunohistochemistry was used to identify reactivity to GAP43 and CGRP protein, an innervation and sensory neuropeptide marker. Lectin histochemistry and histology methods were adopted to analyse glycan expression and tissue restoration in IVD. Results and Discussion: Hydrogel showed resistance to enzymatic degradation after 28 days. NP cells maintained a rounded shape and no statistical difference in metabolic activity. IL-1R1, MyD88, NGF and BDNF were suppressed in the presence of HA hydrogels (Figure 1). HA hydrogel in the in vivo injury model revealed a significant decrease of sensory innervation in NP and annulus fibrosus (AF) tissue (Figure 2). Sialic acids was identified in the extracellular matrix of both NP and AF. High mannose was expressed in AF and NP cells. The presence of α-galactose in the ECM of AF and NP was determined by GS-I-B4 (Figure 3). Conclusion: No cytotoxicity of HA hydrogels was observed in NP cells. A potential therapeutic effect of HA hydrogel was supported by data demonstrating a suppression of inflammation and neurotrophins in the inflammation model, and inhibition of in vivo hyper-innervation associated pain in response to the injury so as to promote disc regeneration. Majlis Amanah Rakyat (MARA) Malaysia and AO Research Institute – Collaborative Research Programme for providing financial support to this project. This publication has emanated from research supported in part by a research grant from Science Foundation Ireland (SFI) and is co-funded under the European Regional Development Fund under Grant Number 13/RC/2073.References:[1] Isa I. L. M.; Srivastava A.; Tiernan D.; Owens P.; Rooney P.; Dockery P.; Pandit A. Biomacromolecules. 2015.16. 1714-1725[2] Caires, R.; Luis, E.; Taberner, F. J.; Fernandez-Ballester, G.; Ferrer-Montiel, A.; Balazs, E. a.; Gomis, A.; Belmonte, C.; de la Peña, E. Nat. Commun. 2015, 6, 8095.[3] Collin, E. C.; Grad, S.; Zeugolis, D. I.; Vinatier, C. S.; Clouet, J. R.; Guicheux, J. J.; Weiss, P.; Alini, M.; Pandit, A. S. Biomaterials 2011, 32, 2862–2870. Keywords: Hydrogel, in vitro, disc replacement, in vivo tissue engineering Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: General Session Oral Topic: Biomaterials to modulate biological processes involved in host response Citation: Mohd Isa I, Srivastava A, Kilcoyne M, Abbah S, Carroll O, Tiernan D, Owens P, Joshi L, Dockery P, Finn D and Pandit A (2016). Regulation of inflammation, neurotrophins, glycosylation, sensory nerve innervation and pain in intervertebral disc degeneration using an implantable hyaluronic acid hydrogel. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01510 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. * Correspondence: Dr. Isma Liza Mohd Isa, National University of Ireland, Centre for Research in Medical Devices (CÚRAM), Galway, Ireland, Email1 Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Isma Liza Mohd Isa Akshay Srivastava Michelle Kilcoyne Sunny A Abbah Oliver Carroll David Tiernan Peter Owens Lokesh Joshi Peter Dockery David P Finn Abhay Pandit Google Isma Liza Mohd Isa Akshay Srivastava Michelle Kilcoyne Sunny A Abbah Oliver Carroll David Tiernan Peter Owens Lokesh Joshi Peter Dockery David P Finn Abhay Pandit Google Scholar Isma Liza Mohd Isa Akshay Srivastava Michelle Kilcoyne Sunny A Abbah Oliver Carroll David Tiernan Peter Owens Lokesh Joshi Peter Dockery David P Finn Abhay Pandit PubMed Isma Liza Mohd Isa Akshay Srivastava Michelle Kilcoyne Sunny A Abbah Oliver Carroll David Tiernan Peter Owens Lokesh Joshi Peter Dockery David P Finn Abhay Pandit Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.