The effect of 8 weeks IGF-1 injection and resistance training on Cox-2 and p53 expression in colorectal of male Wistar rats

The aim of this study was to determine the effect of 8 weeks IGF-1 injection and resistance training on Cox-2 and p53 expression in colorectal of male Wistar rats. A total of 28 male Wistar rats were randomly divided into 4 groups; saline injected control (Control), resistance training+saline injected (Training), resistance training+IGF-1 injected (Combined) and IGF-1 injected (Injection). Resistance training protocol consisted of climbing (three days/week, 5 reps/3 sets) a ladder carrying a load suspended from the tail for 8 weeks. IGF-1 and saline (1.5 µg/kg/day) were injected before and after exercise sessions. Three days after the last bout of exercise, colorectal tissues were collected and gene expression levels were analyzed using real-time PCR. In Training, Combined and Injection groups, p53 expression in the colorectal decreased compared with Control (p<0.05). A significant decrease of Cox-2 protein levels was observed in the Training group from the Control (p=0.002). Cox-2 levels were significantly higher in Injection group compared to Control group (p=0.002). In the Combined group, Cox-2 levels was significantly higher compared to Training group (p=0.018). Taken together, this study demonstrates that IGF-1 injection decrease and increase p53 and Cox-2 expression in the colorectal of mice, respectively. However, resistance training decease p53 and Cox-2 expression, also attenuate decrease and increase p53 and Cox-2 expression altered by IGF-1 injection.