Anti-inflammatory and antioxidative effects of genistein in a model of spinal cord injury in rats

Background: Neurological damage from spinal cord injury (SCI) is a result of primary mechanical injury and secondary damage from oxidative stress and neuroinflammation. Although genistein has been shown to have potent antioxidant and anti-inflammatory effects in studies of brain injury, its effect on secondary damage in SCI has remained unknown. Objective: To determine effects of genistein in a model of SCI in rats. Methods: We divided 21 rats evenly into 3 groups, a control group, in which only a laminectomy was performed; a trauma group in which SCI was induced; and a genistein group in which genistein was administered subcutaneously after SCI. The rats were assessed using a Basso-Beattie and Bresnahan functional score at the 12th hour and on the 1st, 3rd, 5th, and 7th days. Biochemical analyses were conducted at the same time points to determine the serum levels of catalase, ischemia-modified albumin (IMA), disulfide (SS), total thiol (TT), native thiol (NT), disulfide/ total thiol (SS/TT), and native thiol/total thiol (NT/TT). Total oxidant and antioxidant capacity, and oxidative stress index were determined in spinal cord tissue obtained on the 7th day together with immunohistochemistry for cyclooxygenase-2 levels. Result: Catalase activity on the 7th day was significantly (P = 0.001) higher in the genistein-treated rats than in other groups, and IMA levels became stable earlier (3rd day) in the genistein group. SS values were significantly (P = 0.004) lower in the genistein group. NT/TT ratio were significantly (P = 0.049) higher in the genistein-treated rats on the 7th day. Conclusion: Genistein has antioxidant, anti-inflammatory, and protective effects in a model of SCI in rats and warrants further study.