Formation of reactive oxygen species induced by Hcy treatment of podocytes and blockade by NADPH oxidase inhibitors. A. Representative ESR spectra showing O2•− production in different groups of podocytes. B. Summarized data showing O2•− production in different groups of podocytes (n = 6). *p < 0.05 vs. Ctrl group, #p < 0.05 vs. Vehl-Hcy group. Ctrl, control; Vehl, vehicle; gp91 ds-tat, gp91 ds-tat peptide; DPI, diphenyleneiodonium; Hcy, homocysteine.