Fig. 4
Mfn2 ablation caused mitochondrial dysfunction in the brain of Mfn2 cKO mice. Representative western blots (a) and quantification analysis (b) showed changes in the protein levels of key subunits of respiratory complex I (anti-NDUFB8), and II (anti-SDHB) in the hippocampal and cortical tissues of Mfn2 cKO mice since 8 week of age. (c) Respiratory activity of synaptic mitochondria freshly isolated from hippocampus of 8-week-old Mfn2 cKO mice and control mice was analyzed by Seahorse XF Assay. Oxygen consumption (OCR) rate was measured before and after sequential exposure to oligomycin (inhibits ATP synthase, blocks oxygen consumption related to ATP synthesis), FCCP (uncoupler to assess maximal OCR), and antimycin A/rotenone (blocks electron flux through both complex I and II). Quantification of basal (d) and maximal (e) OCR of control and Mfn2 cKO mice. Respiration control ratio (F) (OCRFCCP/OCROligomycin), Spare respiratory capacity (g) (OCRFCCP-OCRBasal) and Coupling efficiency (H) ([OCRBasal -OCROligomycin]/ OCRBasal) were calculated after subtracting the non-mitochondrial respiration (OCRAntimycin A/rotenone). Data are means ± SD of 3 mice. Statistics: Student’s t test. *p < 0.05 and **p < 0.01 compared with control