*2.3. Effects of UPE on Serum Indexes*

The levels of Scr, BUN, and Cys-C in serum and kidney are shown in Figure 2b–d. Compared with the control mice, the contents of Scr, BUN, and Cys-C in serum of mice treated with D-gal were increased by 42.06%, 19.94%, and 25.43% (*p* < 0.01), respectively. When feeding low-dose UPE, the contents of Scr and Cys-C were significantly decreased (both *p* < 0.01) compared with the NC group, but there was no statistical significance in the change of BUN level. However, the contents of Scr, BUN, and Cys-C in the high-dose group were significantly decreased (28.76%, 12.65%, and 16.76%, respectively, *p* < 0.01), indicating that UPC had a protective effect on kidney injury induced by D-gal in mice.
