Fig 2: Cell viability and Glo1 function in HUVECs. HUVECs were treated with 400 μM MG and glycine (0.5 mM-4 mM) for 72 h. (a) Cell viability determined by CCK-8. The experiment was performed in triplicate and repeated four times. (b) Intracellular GSH/GSSG ratio in HUVECs. The experiment was performed in triplicate and repeated three times. (c) The activity of Glo1 in HUVECs. The experiment was performed in triplicate and repeated four times. Control: cells incubated in MEM. The medium for all controls and experimental samples had a glucose level of 5.5 mM. MG: methylglyoxal. Gly: glycine. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001 compared with the control group. #p < 0.05, ##p < 0.01, ###p < 0.001 compared with cells treated with 400 μM MG.

Fig 3: Alterations in Glo1 activity and AGE levels after incubation with the Glo1 inhibitor BBGC for 72 h. Before adding MG and glycine into the medium, the cells in the BBGC group were pretreated with 4 μM BBGC for 12 h. (a) The activity of Glo1 in HUVECs. The experiment was performed in triplicate and repeated four times. (b) Intracellular AGE levels determined by ELISA. The experiment was performed in triplicate and repeated three times. BBGC: S-bromobenzylglutathione cyclopentyl diester. ∗∗p < 0.01 compared with the control group. #p < 0.05, ##p < 0.01 compared with cells treated with 400 μM MG.

Fig 4: Western blot analysis of glyoxalase 1 (GLO1) (a) and GLO2 (b) and representative images of immunoreactive bands (c). Data are presented as means ± SEM of densitometric analysis of immunoreactive bands normalized to internal reference protein (glyceraldehyde-3-phosphate dehydrogenase, GAPDH). Three mice per experimental group were employed. Experiments were done in triplicate. ***, p < 0.001, t-test.

Fig 5: Immunohistological and immunoblot analyses of Glo1 and Glo1 activity measurements in the aorta from different groups after 12 weeks of treatment. (a) and (b) show the immunohistological analysis of Glo1 in the aorta, magnification 400x. The scale bar indicates 20 μm. N = 6. (c) The expression of Glo1 in the rat aorta determined by western blot. N = 6. (d) The activity of Glo1 in the rat aorta. N = 6. ∗p < 0.05, ∗∗p < 0.01 compared with the control group. #p < 0.05, ##p < 0.01 compared with the DM group.