Anti-inflammatory effect of oleuropein in experimental rat spinal cord trauma

Abstract

Background: Spinal cord injury stimulates an inflammatory reaction that causes substantial secondary damage inside the injured spinal tissue. The purpose of this study was to determine the anti-inflammatory effect of oleuropein on traumatized spinal cord.

Methods: Rats were randomly divided into four groups of 7 rats each as follows: Sham-operated group, trauma group, and oleuropein treatment groups (20 mg/kg, ip, immediately and 1 hour after spinal cord injury). Spinal cord samples were taken 24 hours after injury and studied for immunohistochemistry of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), nitrotyrosine, inducible nitricoxide synthase (iNOS), cyclooxygenase-2 (COX-2), and poly(ADP-ribose) polymerase (PARP).

Results: Attenuated TNF-α, IL-1ß, nitrotyrosine, iNOS, COX-2, and PARP expression could be detected in the oleuropein-treated rats.

Conclusion: Oleuropein modulates inflammatory reactions following spinal cord injury.

Keywords: Inflammation; Oleuropein; Rat; Spinal cord; Trauma.

Fig. 1

Immunohistochemical expression of COX-2, iNOS, nitrotyrosine, PARP, TNF-α, and IL-1β. Light photomicrographs show COX-2 reactivity (A1=sham; A2=trauma; A3=OE treatment), iNOS reactivity (B1=sham; B2=trauma; B3=OE treatment), nitrotyrosine reactivity (C1=sham; C2=trauma; C3=OE treatment), PARP reactivity (D1=sham; D2=trauma; D3=OE treatment), TNF-α reactivity (E1=sham; E2=trauma; E3=OE treatment), and IL-1β reactivity (F1=sham; F2=trauma; F3=OE treatment) 24 hours after injury (magnification, ×200). The positive staining of the antigens is presented by a brown color.