Effects of EPC-K1 on lipid peroxidation in experimental spinal cord injury

Study Design. A study in which levels of lipid peroxidation were measured, the thiobarbituric acid-reactive substances were estimated in an experimental rat model, and the recovery was assessed. Objective. To ascertain the occurrence of thiobarbituric acid-reactive substances in the damaged spinal cord, and to investigate the effectiveness of a hydroxyl radical scavenger EPC-K1, a phosphate diester linkage of vitamins E and C, in attenuating the severity of spinal cord injury. Summary of Background Data, Lipid peroxidation has been reported to play an important role in spinal cord injury. There is no report on the use of EPC-K1 to attenuate the severity of spinal cord injury in either animal or human studies. Methods. Spinal cord injury was induced by placing a 25-g weight on T12, and the animals were divided into six groups. Group 1 (sham) received only laminectomy. Group 2 (control) received spinal cord injury. Group 3 received EPC-K1 5 minutes before injury. Group 4 received it 5 minutes after injury. Group 5 received it 3 hours after injury. Group 6 received it five limes, respectively: at 5 minutes, then 1, 2, 3, and 4 hours after injury. The levels of thiobarbituric acid-reactive substances were measured in the spinal cord, and the recovery was assessed. Results. The thiobarbituric acid-reactive substances content increased after injury, with two peaks, at 1 and 4 hours. Concentration at the 4-hour peak was lower in nitrogen mustard-induced leukocytopenia rats than in the control rats. The EPC-K1 injection reduced thiobarbituric acid-reactive substances content at 1 and 4 hours after injury in Group 3 (respectively, 34.3% and 42.7% vs. conrol) andonly that at 4 hours in Group 6 (24.9% vs, control). Motor function recovery and histologic findings were better in these two groups than in Group 2, Conclusion. Repeated injection of EPC-K1 attenuated the severity of spinal cord injury.