formation of acylcarnitines, formed by incomplete b-oxidation, is also linked to insulin resistance in conditions of high fatty acid availability [48]. In our study, we observed that DGAT1 overexpression improved muscle insulin sensitivity in parallel with increased expression of markers of mitochondrial function such as PGC1a as well as the OXPHOS complexes. Liu et al. [14] also reported that DGAT1 overexpressing muscles appeared to have a greater mitochondrial fatty acid oxidation efficiency. These data could suggest that in our model acylcarnitines may be reduced, thereby explaining the improved insulin sensitivity. Unfortunately, due to the limited amount of muscle sample available and our prioritization of DAG and ceramide analysis, the reliable determination of long- and medium-chain acylcarnitines was not possible. However, we could reliably measure levels for free carnitine and acetylcarnitine, which were unaffected by our intervention. 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