scholarly journals Identification and characterization of glycanated and non-glycanated forms of biglycan and decorin in the human intervertebral disc

1993 ◽  
Vol 292 (3) ◽  
pp. 661-666 ◽  
Author(s):  
B Johnstone ◽  
M Markopoulos ◽  
P Neame ◽  
B Caterson

Immunological studies revealed the presence of several different forms of biglycan and decorin in human intervertebral-disc tissues (annulus fibrosus, nucleus pulposus and cartilage end-plate). In the young intervertebral disc, glycosaminoglycan-containing (glycanated) forms of both biglycan and decorin represented a greater proportion of the total proteoglycan population present in extracts of annulus fibrosus and cartilage end-plate compared with extracts of nucleus pulposus, in which they were barely detectable. In older discs the glycanated forms of biglycan and decorin represented only a small proportion of the total proteoglycan present. Immunochemical analyses with an antibody to chondroitin/dermatan sulphate isomers indicated differences in the glycosaminoglycans substituted on glycanated forms of small proteoglycans found in different disc tissues. Dermatan sulphate was the predominant glycosaminoglycan present on biglycan and decorin in annulus fibrosus extracts, whereas chondroitin 4-sulphate was present in both small proteoglycans isolated from cartilage end-plate. In addition, immunochemical analyses with antibodies against core protein epitopes identified two non-glycanated forms of both biglycan and decorin. These non-glycanated forms of the small proteoglycans were found in all three regions of the disc. The two nonglycanated forms of biglycan had estimated molecular masses of 37 and 41 kDa and those of decorin were 43 and 45 kDa, respectively. These non-glycanated forms of biglycan and decorin increased in proportion with aging. N-terminal sequence analysis indicated that the larger non-glycanated form of decorin was a degradation product of its glycanated precursor. However, no N-terminal sequence information was obtainable from the other non-glycanated form of decorin or the two non-glycanated forms of biglycan. These data are consistent with the hypothesis that some of the non-glycanated forms of decorin and biglycan are degradation products of native precursors. However, the possibility remains that several different post-translationally modified forms of decorin and biglycan are synthesized by intervertebral-disc tissues.

1997 ◽  
Vol 326 (1) ◽  
pp. 235-241 ◽  
Author(s):  
Robert SZTROLOVICS ◽  
Mauro ALINI ◽  
Peter J. ROUGHLEY ◽  
John S. MORT

Aggrecan degradation in human intervertebral disc and articular cartilage has been studied by using anti-neoepitope antibodies specific for the N-terminal degradation products generated by cleavage within the interglobular domain at the metalloproteinase and aggrecanase sites. Immunoblot analysis of extracts of annulus fibrosus, nucleus pulposus and articular cartilage demonstrated age-related patterns in the abundance of both degradation products. In all three tissues the metalloproteinase-generated fragment was present at very low levels in young individuals but increased in abundance with age. In the disc tissues, the abundance of this degradation product levelled off in the juvenile; for cartilage this occurred in early adulthood. Despite these temporal differences, the levels attained in adults were comparable for the three tissues. In contrast, the aggrecanase-generated degradation product exhibited tissue-specific differences in the variation of its abundance with age. Whereas this degradation product increased with age in annulus fibrosus and articular cartilage and had levelled off by adulthood, in nucleus pulposus it was present in greatest abundance in young individuals and decreased to very low levels with age. Examination of discs exhibiting various degrees of degeneration did not reveal any differences in the levels of the metalloproteinase and aggrecanase-generated cleavage products that could not be accounted for by differences in age. In adults the product of aggrecanase action was much more abundant in articular cartilage than in either of the disc tissues, despite the age-related increase also observed for annulus fibrosus. Analysis of tissue extracts with an antibody recognizing the G1 domain of aggrecan identified two major degradation products whose abundance and size were correlated with the fragments detected by the anti-neoepitope antibodies. Taken together, these results indicate that cleavage at the metalloproteinase and aggrecanase sites are quantitatively important events in aggrecan catabolism in both articular cartilage and intervertebral disc in vivo. Moreover the two enzyme systems act independently and exhibit differences in the degree to which they contribute to aggrecan degradation in these tissues.


Author(s):  
John McMorran ◽  
Diane Gregory

Abstract In light of the correlation between chronic back pain and intervertebral disc degeneration, this literature review seeks to illustrate the importance of the hydraulic response across the nucleus pulposus- annulus fibrosus interface, by synthesizing current information regarding injurious biomechanics of the spine, stemming from axial compression. Damage to vertebrae, endplates, the nucleus pulposus, and the annulus fibrosus, can all arise from axial compression, depending on the segment's posture, the manner in which it is loaded, and the physiological state of tissue. Therefore, this movement pattern was selected to illustrate the importance of the bracing effect of a pressurized nucleus pulposus on the annulus fibrosus, and how injuries interrupting support to the annulus fibrosus may contribute to intervertebral disc degeneration.


2015 ◽  
Vol 84 (3) ◽  
pp. 157-166
Author(s):  
Witold Woźniak ◽  
Małgorzata Grzymisławska ◽  
Joanna Łupicka ◽  
Małgorzata Bruska ◽  
Adam Piotrowski ◽  
...  

Introduction. In the vast literature concerning the development of the intervertebral discs controversies exist as to the period of differentiation and structure of the nucleus pulposus and annulus fibrosus. These controversies result from different determination of age of the investigated embryos. Aim. Using embryos from departmental collection age of which was established according to international Carnegie staging and expressed in postfertilizational days, the differentiation of the intervertebral discs was traced. Material and methods. Study was performed on 34 embryos at developmental stages 13–23 (32–56 days). Embryos were serially sectioned in sagittal, frontal and horizontal planes. Sections were stained with various histological methods and impregnated with silver.Results. Division of sclerotomes into loose cranial and dense caudal zones (sclerotomites) was observed in embryos aged 32 days (stage 13). The intervertebral disc developed from the dense zone of sclerotome and was well recognized in embryos aged 33 days (stage 14). At the end of fifth week (embryos at stage 15, 36 days) the annulus fibrosus and the nucleus pulposus were seen. The annulus fibrosus differentiated into lateral and medial zones. Within the lateral zone cells were arranged into circular rows. These rows were considered as the first stage of laminar structure. In further developmental stages the laminae occupied both zones of the annulus fibrosus.Conclusions. The intervertebral discs develop from the dense zone of the sclerotome which is evident in embryos at stage 13 (32 days). Discs differentiate in embryos aged 33 days, when the nucleus pulposus and annulus fibrosus are recognized. In embryos aged 36 days in the annulus fibrosus circular rows forming laminar arrangement are seen.


Author(s):  
Guus G. H. van den Akker ◽  
Andy Cremers ◽  
Donatus A. M. Surtel ◽  
Willem Voncken ◽  
Tim J. M. Welting

Author(s):  
David T. Korda ◽  
Delphine Perie ◽  
James C. Iatridis

The intervertebral disc provides flexibility and load support for the spine. It consists of two main regions; the outer annulus fibrosus which is a highly organized collagen matrix and the inner nucleus pulposus which (in a healthy disc) is a proteoglycan rich gelatinous material. The predominant mode of loading on the intervertebral disc is axial compression, which generates hydrostatic pressures within the disc. The high water content of the nucleus plays a major role in supporting these loads. With age and degeneration, the water content of the nucleus changes, and is believed to significantly impact its ability to bear load. The purpose of this study therefore, was to define the effects of swelling conditions (which affect disc hydration) on the material properties of the disc under compressive loading.


2021 ◽  
Author(s):  
Audrey McAlinden ◽  
David M Hudson ◽  
Aysel A Fernandes ◽  
Soumya Ravindran ◽  
Russell J Fernandes

For next generation tissue-engineered constructs and regenerative medicine to succeed clinically, the basic biology and extracellular matrix composition of tissues that these repair techniques seek to restore have to be fully determined. Using the latest reagents coupled with tried and tested methodologies, we continue to uncover previously undetected structural proteins in mature intervertebral disc. In this study we show that the ″embryonic″ type IIA procollagen isoform (containing a cysteine-rich amino propeptide) was biochemically detectable in the annulus fibrosus of both calf and mature steer intervertebral discs, but not in the nucleus pulposus where the type IIB isoform was predominantly localized. Specifically, the triple-helical type IIA procollagen isoform immunolocalized in the outer margins of the inner annulus fibrosus. Triple helical processed type II collagen exclusively localized within the inter- lamellae regions and with type IIA procollagen in the intra-lamellae regions. Mass spectrometry of the a1(II) collagen chains from the region where type IIA procollagen localized showed high 3-hydroxylation of Proline-944, a post- translational modification that is correlated with thin collagen fibrils as in the nucleus pulposus. The findings implicate small diameter fibrils of type IIA procollagen in select regions of the annulus fibrosus where it likely contributes to the organization of collagen bundles and structural properties within the type I- type II collagen transition zone.


2022 ◽  
Author(s):  
Remy E Walk ◽  
Hong Joo Moon ◽  
Simon Y Tang ◽  
Munish C Gupta

Study Design: Preclinical animal study. Objective: Evaluation of the degenerative progression resulting from either a partial- or full- width injury to the mouse lumbar intervertebral disc (IVD) using contrast-enhanced micro-computed tomography and histological analyses. We utilized a lateral-retroperitoneal surgical approach to access the lumbar IVD, and the injuries to the IVD were induced by either incising one side of the annulus fibrosus or puncturing both sides of the annulus fibrosus. The full-width injury caused dramatic reduction in nucleus pulposus hydration and significant degeneration. A partial-width injury produces localized deterioration around the annulus fibrosus site that resulted in local tissue remodeling without gross degeneration to the IVD. Methods: Female C57BL/6J mice of 3-4 months age were used in this study. They were divided into three groups to undergo a partial-width, full-width, or sham injuries. The L5/L6 and L6/S1 lumbar IVDs were surgically exposed using a lateral-retroperitoneal approach. The L6/S1 IVDs were injured using either a surgical scalpel (partial-width) or a 33G needle (full-width), with the L5/L6 serving as an internal control. These animals were allowed to recover and then sacrificed at 2-, 4-, or 8- weeks post-surgery. The IVDs were assessed for degeneration using contrast-enhanced microCT (CEμCT) and histological analysis. Results: The high-resolution 3D evaluation of the IVD confirmed that the respective injuries localized within one side of the annulus fibrosus or spanned the full width of the IVD. The full-width injury caused deteriorations in the nucleus pulposus after 2 weeks that culminated in significant degeneration at 8 weeks, while the partial width injury caused localized disruptions that remained limited to the annulus fibrosus. Conclusion: The use of CEμCT revealed distinct IVD degeneration profiles resulting from partial- and full- width injuries. The partial width injury may serve as a better model for IVD degeneration resulting from localized annulus fibrosus injuries in humans.


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