Inhibition of both endplate nutritional pathways results in intervertebral disc degeneration in a goat model

Abstract

Background The vertebral endplate route was demonstrated to be the main pathway for nutrition to the intervertebral disc. However, it is still a controversial issue on whether the blocking of the endplate nutritional pathway could result in intervertebral disc degeneration (IDD) in animal models. The aim was therefore to investigate the effect of the inhibition of both endplate nutritional pathways by bone cement injection on the IDD in a goat model. Methods Two lumbar intervertebral discs (L2–3 and L3–4) in eight 24-month-old goats were blocked in both endplate nutritional pathways by cement injection, and the other two lumbar intervertebral discs (L1–2 and L4–5) remained intact as normal controls. Effective blocking area percentage in nucleus pulposus (NP) was calculated, and X-rays, magnetic resonance imaging (MRI), and histology studies were performed at 4, 12, 24, and 48 weeks after operation. Results The mean effective blocking area percentage was 60.7 ± 5.3%. Imaging examinations at the time of 48 weeks after blocking the endplate nutritional pathways showed obvious IDD, with larger disc height reduction and higher degrees of disc degeneration grading compared with the normal controls. Histological examinations including HE, Masson’s trichrome, Sirius Red, and proteoglycan stainings also confirmed the degenerative changes of the blocked discs. Conclusions The endplate nutritional route could be inhibited by blocking both endplate pathways with cement injection in a goat model. The severe inhibition in the endplate nutritional pathways may result in IDD.

Characterization of bovine and canine animal model cartilage endplates and comparison to human cartilage endplate structure, matrix composition, and cell phenotype

“…This phenomenon is not observed in the non‐chondrodystrophic dog breeds but is also seen in ovine models, making the sheep model a candidate for further characterization 33 . Additionally, the goat has been used as an effective translational model to evaluate the impact of disc nutrition and CEP permeability on the etiology of IVD degeneration 34 …”

“…33 Additionally, the goat has been used as an effective translational model to evaluate the impact of disc nutrition and CEP permeability on the etiology of IVD degeneration. 34 This study provides valuable insight into species specific differences between the human, bovine and canine CEP on the structural, however, for the current study we focused on bovine because of its similarities to the structure and cell composition of the healthy human IVD 35 and the chondrodystrophic dog given its utility as a model for IVD degeneration and back pain. 16…”

A Momentary Impact Injury of Vertebral Endplates, even without Structural Disruption, Initiates Disc Degeneration In Vitro.

“…It is well known that, the nutritional pathways that into the nucleus pulposus of human intervertebral discs are mainly by diffusion through the central portion of the end-plate from these marrow space cartilage contacts [11]. Thus, a functional intact endplate is crucial to transport nutrients and waste products by diffusion [31,32].Dudli et al [8] characterized the process of disc degeneration using an in vitro full-organ model, and elucidated that burst endplates, but not equienergetic loading promoted disc degeneration. However, Chan et al [33] reported that, impact load which was generally sub-traumatic, could also cause cumulative damage and injury to the lumbar spine.…”

A Momentary Impact Injury of Vertebral Endplates, even without Structural Disruption, Initiates Disc Degeneration In Vitro.

“…It is well known that, the nutritional pathways that into the nucleus pulposus of human intervertebral discs are mainly by diffusion through the central portion of the end-plate from these marrow space cartilage contacts [11]. Thus, a functional intact endplate is crucial to transport nutrients and waste products by diffusion [31,32].Dudli et al [8] characterized the process of disc degeneration using an in vitro full-organ model, and elucidated that burst endplates, but not equienergetic loading promoted disc degeneration. However, Chan et al [33] reported that, impact load which was generally subtraumatic, could also cause cumulative damage and injury to the lumbar spine.…”