Compared with 0 week, the serum C-peptide level at 8 week was decreased in the T1DM mice treated with insulin or T1DM, while it was increased in T1DM mice treated with exenatide, hUCMSCs, or hUCMSCs@Ex-4, among which, treatment with hUCMSCs@Ex-4 contributed to more significant increases relative to hUCMSCs (Fig. 2D). Here, INS is linked to type 1 diabetes mellitus.