TRAF6 and diabetes mellitus: Compared with the CON group, TLR4, IRAK1, TRAF6, NF-κB, and collagen I were upregulated in diabetic rats, while suppressed in DM+DAPA group (TLR4: 1.008 ± 0.3615 vs. 1.519 ± 0.2976 vs. 0.9314 ± 0.2746, P = 0.0140; IRAK1: 1.141 ± 0.4182 vs. 1.712 ± 0.5146 vs. 0.8939 ± 0.3516, P = 0.0030; TRAF6: 1.083 ± 0.2963 vs. 2.033 ± 0.6714 vs. 1.169 ± 0.4642, P = 0.0029; NF-κB: 0.6789 ± 0.2403 vs. 1.552 ± 0.5397 vs. 1.099 ± 0.2456, P = 0.0003; collagen I: 0.5637 ± 0.2079 vs. 1.387 ± 0.3925 vs. 0.6279 ± 0.1973, P = 0.0015) (shown as in Figures 5A–E).