Effects of vertebral fusion on levels of pro-inflammatory and catabolic mediators in a rabbit model of intervertebral disc degeneration

Özet

Objective: The aim of this study was to explore the alterations in levels of pro-inflammatory and catabolic mediators followingvertebral fusion in a rabbit model of intervertebral disc degeneration.Methods: In this study, 24 female New Zealand albino rabbits (aged 4 to 5 months and weighing 3 to 3.5 kg) were used. All theanimals were randomly categorized into four groups, and dorsal spinal exposure of all lumbar vertebrae was routinely performedin each group. While disc degeneration was created in groups B, C, and D, spinal fusion was added to disc degeneration in groupsC and D. Disc degeneration was typically created by puncturing the discs with an 18-gauge needle under the guidance of C-armimaging. Fusion was achieved with posterior/posterolateral decortication and iliac bone grafts. The rabbits in groups A, B, and Cwere euthanized, and the discs were removed in the first week after the surgery. The rabbits in Group D were sacrificed, and thediscs were harvested at 5 weeks after the surgery. The levels of Interleukin (IL)-1β, IL-6, Nitric Oxide (NO), MatrixMetalloproteinase (MMP)-3, MMP-13, and Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) in the discs were analyzed usingenzyme-linked immunosorbent assay kits.Results: Significant increase was observed in the protein levels of both pro-inflammatory and catabolic mediators in discdegeneration groups (Group B, C, and D) compared to Group A. In the fusion groups (Group C and D), these increasedmediators decreased, compared to non-fusion group (Group B), (IL1-β P = 0.017, TIMP-1 P = 0.03, NO P = 0.03). However,there was no statistically significant difference in mediator levels between the short- and long-term fusion (Group C versus D).Conclusion: The results of this study have shown that a significant decrease in pro-inflammatory and catabolic mediators may beexpected after vertebral fusion whereas there may be no significant difference between the first and fourth week of fusionsurgery. These findings may contribute to clarifying the mechanism of action of vertebral fusion in the treatment of low backpain.