As shown in Figure 3, placental p-4EBP1(Thr-37/46) (0.87 ± 0.06 vs. 0.69 ± 0.12, normal vs. STZ-D, p < 0.05) and p-S6k1(Thr-389) (0.72 ± 0.06 vs. 0.51 ± 0.09, normal vs. STZ-D, p < 0.05) expressions were significantly reduced in STZ-D rats compared with normal rats, which suggested that severe pregestational diabetes could decrease placental mTORC1 signaling activity. This evidence concerns the gene RPS6KB1 and diabetes mellitus.