Effect of 2-methoxyestradiol on phosphorylation of Tau protein and motor function of rats after spinal cord injury

Abstract

Objective To investigate the effect of 2-methoxyestradiol (2ME2) on phosphorylation of Tau protein (p-Tau) and mortor function of rats after spinal cord injury (SCI).Methods A total of 72 adult male Sprague-Dawley rats were randomly divided into 3 groups:sham-operated group (n=24),SCI group (n=24) and SCI+2ME2 treated group (n=24); models of SCI were created by modified Allen's method; one d after SCI,rats in the SCI+2ME2 treated group were given intraperitoneal injection of 2ME2 (24 mg/kg) for seven d,and rats in the SCI group were given the same volume of normal saline.Basso,Beatti,Bresnahan (BBB) scale was performed to evaluate the hindlimb function one,three,seven,14,21 and 28 d after SCI; the expression changes ofp-Tau (Ser 262) seven d after SCI were observed by immunofluorescence and Western blotting.Results BBB scale scores in the SCI group and SCI+2ME2 group were significantly increased following the prolonging of injury times (1-28 d of injury,P＜0.05); on the 7th,14th,21st and 28th d of injury,the scores in the SCI+2ME2 group were significantly higher than those in the SCI group (P＜0.05).The p-Tau positive cells in the spinal cord and the p-Tau (Ser 262) expression in the SCI group and SCI+2ME2 group were significantly increased as compared with those in the sham-operated group (P＜0.05),and those in the SCI+2ME2 group (19.05± 1.34 and 0.283±0.094) were obviously lower as compared with those in the SCI group (10.36±1.28 and 0.607±0.105,P＜0.05).Conclusion 2ME2 offers protection in rats with SCI by reducing the level of tau phosphorylation. Key words: Spinal cord injury; 2-methoxyestradiol; Tau protein; Phosphorylation;