Fig. 3

Effects of neuroinflammation and oxidative stress on axonal mitochondrial morphology. a-c Mitochondrial size parameters: a area, b external perimeter, and c Feret’s diameter. a Axonal mitochondria increase their area in conditions of neuroinflammation and oxidative stress. b However, the external perimeter only increases significantly during neuroinflammation, c while Feret’s diameter also has a tendency to increase in the neuroinflammatory condition. d-f Mitochondrial shape descriptors: d circularity, e roundness, and f aspect ratio. Axonal mitochondria are more rounded following oxidative stress than in unstimulated and LPS-stimulated cultures. g The ratio between the internal cristae perimeter and the external perimeter indicates that both neuroinflammation and oxidative stress induce an increase in axonal mitochondrial cristae complexity. a-g n = 73 control mitochondria, 50 LPS-challenged mitochondria and 75 H₂O₂-challenged mitochondria from two different experiments: Kruskal-Wallis test and Dunn’s multiple comparisons post hoc test. Mean ± SEM. (AU arbitrary units); *p < 0.05, **p < 0.01, ***p < 0.001. h Representative TEM images of axonal mitochondria from unstimulated, LPS-, and H₂O₂-stimulated organotypic cerebellar slice cultures. Scale bars 500 nm