The effect of combined hyperbaric oxygen and iloprost treatment on the prevention of spinal cord ischaemia-reperfusion injury: an experimental study

Abstract

Hyperbaric oxygen (HBO) has been shown to be effective in preventing neurological injuries in animal models of ischaemia, whereas iloprost (IL) prevents ischaemia-related mitochondrial dysfunction and reduces infarction size after focal cerebral ischaemia in animal models. the aim of the present study was to investigate the effect of combined HBO and IL treatment on spinal cord ischaemia-reperfusion (IR) injury by neurological, histopathological and biochemical methods in an experimental study. Eighty New Zealand white male rabbits were randomly allocated into one of five study groups. the HBO group received a single session of HBO treatment and the IL group received an infusion of 25 ng/kg/min IL; the HBO + IL group received both HBO and IL and the control group received only 0.9% saline; the fifth group was the sham group. Levels of S100 beta protein, neuron-specific enolase (NSE) and nitric oxide (NO) were measured at onset, at the end of ischaemia period and at the 24th and 48th hour of reperfusion. Physical activity was assessed using Tarlov criteria 24, and the spinal cords of the sacrificed rabbits were evaluated histopathologically. Additionally, tissue malondialdehyde (MDA) and antioxidant enzyme activities [total superoxide dismutase (SOD); catalase (CAT) and glutathione peroxidase (GSH-Px) were assessed. Neurological scores in the HBO, IL and HBO + IL groups were statistically significantly better compared with the control group at the 24th (P = 0.001 for all) and 48th hour (P = 0.001 for all). Histopathological scores in the HBO, IL and HBO + IL groups were also significantly better compared with the control group (P = 0.003, 0.001 and 0.001, respectively). Whereas MDA, NSE, S100 beta protein and NO concentrations were significantly lower, CAT and GSH-PX levels were significantly higher in either sham or treatment groups compared with the control group. Since we demonstrated beneficial effects on spinal cord IR injury, we think that both HBO and IL, either alone or in combination, may be reasonable in the treatment of IR injury. Furthermore, there did not appear to be synergistic effects with combined treatment. More research is needed for practical application in humans, following thoracoabdominal aortic surgery.