24-Epibrassinolide, a Phytosterol from the Brassinosteroid Family, Protects Dopaminergic Cells against MPP+-Induced Oxidative Stress and Apoptosis
Figure 3
Rhodamine detection of ROS in neuronal PC12 cells after 3-hour and 24-hour treatment. Nonfluorescent DHR is converted to fluorescent rhodamine in the presence of several free radicals (OH•, NO2•, CO3•−, H2O2, HOCl, ONOO−). (a) Fluorescence microphotographs after 3-hour or 24-hour treatment. Cells were pretreated with 24-Epi or vehicle (Ctrl) for 3 h. Then, they were treated or not with MPP+ for 3 h or 24 h. A marked signal of fluorescent rhodamine is evident in neuronal cells treated with MPP+ but not in those exposed to the vehicle (Ctrl) or 24-Epi alone (24-Epi). A striking reduction of fluorescence is evident in cells pretreated with 24-Epi and then treated with MPP+ (24-Epi + MPP+) compared to cells pretreated with vehicle and treated with MPP+ (MPP+). (b) Semiquantitative image analysis of fluorescent cells after 3-hour and 24-hour treatment. Data are expressed as relative fluorescent units and are means ± S.E.M. Magnification 400x. . versus Ctrl and versus MPP+.
