Etanercept Prevents Histopathological Damage after Spinal Cord Injury in Rats

BACKGROUND: The aim of our study is to assess the neuroprotective effects of the tumor necrosis factor alpha (TNF-α) inhibitor etanercept (ETA) on histopathological and biochemical changes following spinal cord injury (SCI). PATIENTS AND METHODS: Fifty-four male Wistar albino rats were randomly assigned into three main groups: The sham, trauma, and ETA group (n = 18 per group). Each of these groups was further divided into three subgroups (n = 6 per subgroup) based on the different tissue sampling times postinjury: 1 h, 6 h, and 24 h. Clip compression model was used for SCI. Rats in the ETA group were treated with 5 mg/kg of ETA immediately after the clip was removed. After 1, 6, and 24 h, the spinal cord was totally removed between the levels T8–T10. Sample tissue was immediately harvested and fixed for histopathological and electron microscopic examination and were analyzed for TNF-α, interleukin-1β (IL-1β), superoxide dismutase (SOD), adenosine deaminase, catalase (CAT), and malondialdehyde levels in both the tissue and serum. RESULTS: The serum and tissue levels of cytokines and enzymes were seen to change after SCI between hyperacute, acute, and subacute stages. Treatment with ETA selectively inhibited TNF-α, and IL-1β expression together with increased levels of antioxidative enzymes (SOD, CAT). CONCLUSION: Early administration of ETA after SCI may remarkably attenuate neuronal injury by decreasing tissue and serum TNF-α and IL-1β levels, while increasing antioxidative enzymes such as SOD and CAT in subacute and acute stages, respectively.