SOD1 and fetal growth restriction: The effects of IUGR on colonic mucosal oxidative and inflammatory-related gene expressions are shown in Figure 3B and Figure 4B. Compared with the NBW pigs, colonic IL-10, SOD-1, and GPX-4 expressions were down-regulated, but TNF-α expression was up-regulated in the IUGR pigs at the three BW stages (p < 0.05).