Adipocyte-specific Trx2 KO results in severe mitophagy and mitochondrial dysfunction. (A–C) Serum levels of NEFA (A), adiponectin (B), and leptin (C) in WT and Trx2^ADKO mice (n = 6). (D) Diagram of tricarboxylic acid (TCA) cycle and OXPHOS. Cit1 (citrate synthase), Idh1 (isocitrate dehydrogenase), Kgd1 (α-ketoglutarate dehydrogenase), Lsc1 (succinyl-CoA ligase), Sdh1 (succinate dehydrogenase), Fum1 (fumarase), and Mdh1 (mitochondrial malate dehydrogenase). (E) Immunoblot analysis of Trx2 and rate-limiting enzymes of the tricarboxylic acid cycle and OXPHOS complexes I–V from WT and Trx2^ADKO mice. Protein levels were quantified and presented as fold changes by taking WT as 1.0. n = 4 mice for each group. (F) Real-time PCR analysis of mitochondrial genes in eWAT from WT and Trx2^ADKO mice at 14 and 24 wk (n = 8). (G) Mitochondrial DNA content in eWAT of WT and Trx2^ADKO mice (n = 8). (H) ATP content of mitochondria isolated from eWAT of WT and Trx2^ADKO mice (n = 6). (I) Representative transmission electron micrographs of eWAT sections from WT and Trx2^ADKO mice at 5, 14, and 24 wk (six images/mouse, n = 3 mice/group). Asterisks indicate LDs. Arrowheads indicate mitochondria. Scale bars, 0.5 µm. Squares correspond to the magnified areas (bottom panel). (J–L) Quantification of total number of mitochondria, damaged mitochondria, and ratio of cristae surface area/outer membrane (OM) surface area (six images/mouse, n = 3 mice/group). Quantitative data are presented as mean ± SEM. ns, not significant; *, P < 0.05; **, P < 0.01; ***, P < 0.001 for the indicated comparisons (two-tailed Student’s t test). w, weeks.