PPARGC1A and type 2 diabetes mellitus: We confirmed that the expression of NDUFB8 (complex I) was downregulated (p = 0.039) in SAT of patients with T2D compared with obese controls, whereas expression of genes in the respiratory complexes II-V (SDHD, UQCRC2, COX5A, ATP5B, and ATP5H), the TCA cycle (FH) and fatty-acid oxidation (HADH and ACADS) as well as PPARGC1A were not significantly downregulated in SAT of patients with T2D (Figure 1a–j).