Journal: Redox Biology
Article Title: Excessive ER-mitochondria coupling: A DRP1-driven mechanism underlying mitochondrial dysfunction and impaired autophagy in stress-induced depression-like behavior in mice
doi: 10.1016/j.redox.2026.104121
Figure Lengend Snippet: Disruption of ER-mitochondria contacts improves neuronal function and enhances autophagy in CSDS. A) Strategy for generating Vglut2 neuron-specific GRP75 ( Hspa9 ) knockout mice using Cre-loxP system. B) Representative SIT trajectory heatmaps. C) Behavioral tests including SIT (Interaction, F (1, 44) = 11.16, P = 0.0017; Interaction, F (3, 94) = 3.122, P = 0.0296), SPT (Interaction, F (1, 44) = 4.675, P = 0.0361) and FST (Interaction, F (1, 44) = 5.453, P = 0.0242) were performed in mice. Two-way ANOVA with Tukey's multiple comparisons test. Data are expressed as mean ± SEM (n = 12 mice in each group). ns, p > 0.05, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001. D) The representative TEM images of CA1 neuron (left) and quantitative analysis showed that the distance between mitochondria and ER (right, Interaction, F (1, 16) = 18.58, P = 0.0005), mitochondrial perimeter (Interaction, F (1, 16) = 17.89, P = 0.0006), mitochondrial area (Interaction, F (1, 16) = 20.58, P = 0.0003) and ERMICC ratio quantification (Interaction, F (1, 16) = 1.205, P = 0.2886). Scale: 200 nm; Two-way ANOVA with Tukey's multiple comparisons test. Data are expressed as mean ± SEM (n = 5 mice per group, for each mouse, all mitochondria within neuronal regions from five non overlapping hippocampal fields were analyzed, and the average value was taken as one point). ns, p > 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001. E) The representative traces, amplitude (Interaction, F (1, 28) = 1.152, P = 0.2922) and frequency (Interaction, F (1, 28) = 6.497, P = 0.0166) statistical maps recorded by sEPSC and the frequency accumulation map of sEPSC in CA1 neurons. Two-way ANOVA with Tukey's multiple comparisons test. Data are expressed as mean ± SEM (n ≥ 6 mice in each group). ns, p > 0.05, ∗ p < 0.05, ∗∗ p < 0.01. F) Mitochondrial respiratory function, including basal respiration (Interaction, F (1, 20) = 4.588, P = 0.0447), ATP production (Interaction, F (1, 20) = 4.684, P = 0.0427) and maximum respiratory capacity (Interaction, F (1, 20) = 2.269, P = 0.1476). Two-way ANOVA with Tukey's multiple comparisons test. Data are expressed as mean ± SEM (n = 6 mice in each group, three mice with six hippocampus). ns, p > 0.05, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001. G) Typical transmission electron microscopy showed quantitative analysis of hippocampal CA1 autophagy (Interaction, F (1, 16) = 13.64, P = 0.0020). Autophagosome is shown in red. Two-way ANOVA with Tukey's multiple comparisons test. Data are expressed as mean ± SEM (n = 5 mice in each group, for each mouse, all mitochondria within neuronal regions from five non overlapping hippocampal fields were analyzed, and the average value was taken as one point). ns, p > 0.05, ∗∗ p < 0.01. H) Representative images of LAMP1 (red), Vglut2 (green) and DAPI (blue) fluorescence in hippocampal CA1 region (lef). The percentage of co-localized fluorescence was quantified (right, n = 7 mice brain slices). Scale bar: 50 μm. Two-way analysis of variance using sidak multiple comparison test (Interaction, F (1, 24) = 26.58, P < 0.0001). The data were expressed as mean ± SEM. ns, p > 0.05, ∗∗∗ p < 0.001.
Article Snippet: Multiplex staining was performed using TSA-based immunofluorescence with primary antibodies: Drp1 (CST 12741S, 1:100), MAP2 (ab32454, 1:1000), GFAP (CST 12389, 1:400), IBA1 (ab178846, 1:1000), Vglut1 (CST #27181, 1:800), Vglut2 (ab216463, 1:250), OLIG2 (CST #65915, 1:400), and LAMP1 (CST 99437S, 1:100).
Techniques: Disruption, Knock-Out, Transmission Assay, Electron Microscopy, Fluorescence, Comparison