Effect of DAPT and exogenous SOD on Notch signaling in HG-stressed human podocytes. A: Human podocytes were pretreated with SOD or DAPT for 2 h, after which the cells were subjected to SOD or DAPT treatment and cultured in normal or HG medium for 48 h. Gel-based RT-PCR and RT-qPCR were carried out to analyze the mRNA expression of Notch signaling molecules, VEGF, and nephrin in these treated cells. For *control and @&#HG groups, P < 0.05. B: the protein expression of the indicated genes in the cell samples as described in A was determined by Western blot analysis with specific antibodies. Notch-1 (FL), full-length Notch-1 C: Tube-like formation of HUVECs induced by various conditioned medium. Conditioned medium from human podocytes treated with HG or a combination of HG and SOD or DAPT was used to stimulate tube formation in cultured HUVECs. At least six repeated experiments were performed, and the formation of a tube-like structure was calculated. For *control and #HG groups, P < 0.05. D: Repression of γ-secretase activity by SOD and DAPT in HG-stressed cells. For *control and #HG groups, P < 0.05.