ABSTRACT
Objective To investigate the possible protective effect of adenoviral vector expressing interleukin-1β (IL-1β) small hairpin RNA (shRNA) on spinal cord injury (SCI) and its mechanism in rats.Methods Forty-eight adult male Sprague-Dawley rats were randomly assigned to 4 groups including the Sham, the Vehicle,the Ad-GFP and the Ad-shIL-1β groups.SCI was induced by epidural compression.Motor function of hind limbs was evaluated by Basso-Beattie-Bresnahan (BBB) score, the expressions of green fluorescence in injured spinal cord tissue were observed by fluorescence microscope.Enzyme-linked immunosorbent assay (ELISA) and immunofluorescence were also performed.Results The expressions of green fluorescence in injured spinal cord tissue were observed in the Ad-GFP and Ad-shIL-1β groups one day after SCI.Significant functional improvement was observed in the Ad-shIL-1β group (8.17 ± 1.17, 10.17 ± 0.98 and 11.33 ± 0.82, respectively) compared to the Vehicle (4.00 ± 0.89, 5.67 ± 1.03 and 6.17 ± 1.17, respectively) and Ad-GFP (3.83 ± 0.98, 5.33 ± 1.21 and 5.67 ± 1.03, respectively) groups at 7, 14 and 21 days after SCI (P ＜ 0.05).Rats in the Ad-shIL-1β group had less neuronal loss 21 days after SCI.In addition, IL-1β downregulation significantly decreased IL-1β, tumor necrosis factor-or (TNF-α) and IL-6 levels (138.83 ± 7.96,143.38 ± 10.20 and 120.43 ± 9.79 in Ad-shIL-1β group;169.33 ± 11.45, 172.33 ± 8.26 and 163.00 ± 9.57 in Vehicle group;172.83 ± 10.85,167.48 ± 8.19 and 159.48 ± 10.98 in Ad-GFP group, respectively) one day after SCI (P ＜ 0.05).Conclusion This study demonstrated that the IL-1β downregulation may have potential therapeutic benefits for improving the outcomes after SCI.