Fig. 7.
Metformin decreases superoxide formation in IPH-PAEC. MitoSOX fluorescence for IPH-PAEC (A) decreased as Metformin concentration increased. No change in epifluorescence was seen at 5 × 10−6 M Metformin (B) for 14 h, but the epifluorescence decreased at 5 × 10−5 M (C) and 5 × 10−4 M (D) of Metformin (P < 0.05, E). Dihydroethidium (DHE) staining for total cell superoxide levels (F) was decreased by Metformin in IPH-PAEC (P < 0.05, n = 10, G–J). MnSOD activity increased with Metformin treatment for 24 h (K). The expression of MnSOD did not change at the lower concentrations of Metformin after 24-h treatment but increased at the highest concentration of 5 × 10−4 M (P < 0.05, n = 3). By 48 h, all 3 concentrations increased MnSOD expression (P < 0.05, n = 3, L). *P < 0.05 compared with nontreated IPH-PAEC.