Evaluation of a pGLcNAc-derived Material as an Activator of Intervertebral Disc Tissue Repair

Degeneration of the intervertebral discs is the most common cause of back pain. The early stages of degeneration affect the nucleus pulposus (NP) of the intervertebral discs followed by a rapid degeneration of the annulus fibrosus. Regeneration of the NP may slow down or reverse the progression of t...

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Bibliographic Details
Main Author: Gorapalli, Deepthi
Other Authors: Whyne, Cari
Format: Others
Language:en_ca
Published: 2008
Subjects:
Online Access:http://hdl.handle.net/1807/17172
Description
Summary:Degeneration of the intervertebral discs is the most common cause of back pain. The early stages of degeneration affect the nucleus pulposus (NP) of the intervertebral discs followed by a rapid degeneration of the annulus fibrosus. Regeneration of the NP may slow down or reverse the progression of the disease. A new deacetylated derivative of a marine diatomic glycosaminoglycan was developed to obtain a hydrogel formulation proposed to have a reparative effect on damaged NP tissue. The hydration kinetics and viscoelastic behaviour of the hydrogel under shear were studied and compared with the behaviour of nondegenerated human lumbar NP. In vitro studies were conducted using primary cell cultures treated with the drug to study cell viability and extracellular matrix factor expression. In vivo studies using New Zealand White (NZW) rabbits have also been conducted using MRI to quantify disc volume followed by histological and immunohistochemical analysis. Rheological data has indicated that the elastic component of the hydrogel dominates the viscous component over a frequency range of 0.1 to 15.85 rad/s. Proteoglycan expression of the treated cells was found to be 78.4 ± 1.9 (p<0.05) times higher than the untreated controls. RTPCR and immunohistochemical data from in vitro studies have demonstrated that characteristic the chondrocyte markers, aggrecan and collagen II, are expressed in the treated cells. A comparison of disc volumes at 6 weeks post-op has shown that the treated discs have 41% greater volume than the untreated iii discs (p<0.05). The results obtained in this study demonstrate that the sulfated deacetylated glycosaminoglycan derivative is a promising material to be utilized in treatment of NP degeneration.