Measurement of the mRNA and protein expression of downstream factors of Nrf2 by qPCR and western blotting, respectively, showed that the expression of SOD2, HO-1, and NQO1 was decreased in DM diabetic rats compared to that in control rats, all of which were upregulated in DM/MSC rats after hUCMSC treatment (P < 0.05, Fig. 4d–g). This evidence concerns the gene SOD2 and diabetes mellitus.