Fig. 3. Mitochondrial Superoxide Generation in Response to Hyperglycemia in Cultured DRG Neurons from Diabetic Mice.

DRG neurons were cultured from 24 wk old diabetic db/db mice and non-diabetic db+ littermates. After 3 d in basal (5.7 mM) glucose, neurons were exposed to 25.7 mM glucose for 0, 1, 3, or 5 h and loaded with MitoSOX for the final 30 min, then fixed and examined by confocal microscopy. A representative image from each condition (total n=15 images collected per condition) is shown in (a). In (b–d), the pixel intensities of all images per condition were analyzed using Scion Image software. In (b), the integrated pixel density in a 500 x 500 μm square containing at least 3 neuron cell bodies with associated neurites was measured. In (c), the mean pixel intensity of at least 200 neuron cell bodies per condition was calculated. In (d), the mean pixel intensity of at least 120 distinct 50 μm length segments of neurites was calculated. Bars represent the mean and standard error of the mean for all images. *Indicates a significant change in pixel intensity between time-points, p<0.01. +Indicates a significant change in pixel intensity between db+ and db/db samples at a single time-point, p<0.05