Fig. 3

4-OI ameliorates renal mitochondrial injury and improves mitophagy in LPS-induced AKI in mice and tubular cells. (A) Mitochondria in proximal tubules were examined by TEM. Scale bar: 2 μm. (B) Representative TEM images of autophagosomes (pointed to by the arrowhead in the left two panels) and mitophagosomes (pointed to by the arrowhead in the right two panels) in renal proximal tubule cells. Scale bar: 1 μm. (C) Representative immunofluorescence images of LC3B (green) and TOMM20 (red) in kidney tissues from each group. The nuclei were counterstained by DAPI (blue) (n = 6). Scale bar: 50 μm. (D) Colocalization of LC3B and TOMM20 determined by Pearson’s correlation coefficient (n = 6). (E) Representative western blot bands of LC3B-II, p62, TIMM23, and TOMM20 in kidney cortices (n = 6). (F) Relative band intensity of LC3B-II, p62, TIMM23, and TOMM20 in kidneys (n = 6). (G) BUMPT cells were immunostained with LC3B (green) and TOMM20 (red) to show mitophagy (n = 4). Scale bar: 20 μm. (H) Colocalization of LC3B and TOMM20 determined by Pearson’s correlation coefficient (n = 4). (I) Representative western blot bands of LC3B-II, p62, TIMM23, and TOMM20 in BUNPT cells (n = 4). (J) Relative band intensity of LC3B-II, p62, TIMM23, and TOMM20 (n = 4). Each symbol (circle) represents an independent experiment. Data are presented as means ± SDs. *P < 0.05, **P < 0.01, ***P < 0.001; ns, not significant. TEM, transmission electron microscopy.