Design and Local Application of Controlled Released Drug Delivery System of Chitosan Hydrogel Loaded with Selenium Nanoparticle in Spinal Cord Injury-Induced Rat; Evaluation of Antioxidant Changes in Neural Tissue

Traumatic spinal cord injury (SCI) is one of the serious injuries of the central nervous system. Oxidative stress is considered one of the signs of the secondary phase of SCI. Therefore, the design and local application of controlled released drug delivery system of chitosan hydrogel loaded with selenium nanoparticles in rats with spinal cord injury and also the evaluation of antioxidant changes in nerve tissue were considered as the aim of the present study. For this purpose, experimental spinal cord injury was created in 60 female adult rats and they were randomly divided into three equal groups; 1- Control group; 2- Chitosan hydrogel group and 3- Chitosan hydrogel loaded with selenium nanoparticles group. The activity of some antioxidant enzymes in spinal cord tissue was measured on the 3rd, 7th, 21st, and 28th days after injury. The results clearly showed that the changes in the amount of superoxide dismutase, malondialdehyde, and glutathione peroxidase on the 3rd and 7th days after trauma in the treatment groups were significantly lower than the control group. However, in the treatment groups, the level of catalase enzyme activity was not significant compared to the control group. It is possible that trauma and production of free radicals in the spinal cord (injury site) were less in the 2 treatment groups of the present study. Therefore, by reducing the amount of oxidative stress in the area of damage, chitosan hydrogel loaded with selenium nanoparticles probably has positive effects on the SCI.