Figure 4: Analysis of mitochondrial autophagy. (a)-(b) Analysis of the mitophagy biomarker (BNIP3) and autophagosome regulators (beclin-1 and LC3-II) by western blot (a) and densitometry (b). (c)-(d) Electron microscopic imaging revealed higher population of autophagic vacuoles engulfing mitochondria (indicated by arrows) in MDA-MB-231 (d) than in MCF-10A (c) cells. See supplemental Figure for images at a higher magnification. (e)-(f) Measurement of autophagic flux by western blot (e) and densitometry (f). Autophagic flux was calculated as the difference between LC3-II levels in the absence (0 hr) and presence (4 hr) of autolysosome inhibitors bafilomycin A1 (0.1 μM) and leupeptin (10 μg/mL); –5; , , and .