Fig. 3

iPSC-derived cardiac fibroblasts from DMD patients exhibit high glycolytic capacity. A: The extracellular acidification rate (ECAR) profile of iPSC-derived cardiac fibroblasts subjected to a glycolysis stress test and the individual parameters for glycolysis, glycolytic capacityand glycolytic reserve. iPSC-derived cardiac fibroblasts were seeded to 80,000 cells/well and incubated for 24 h. ECAR was measured under basal conditions followed by the sequential addition of 10 mM glucose, 0.5 µM oligomycin and 100 mM 2-deoxyglucose (2-DG). Each data point represents an ECAR measurement obtained from the six biological samples of different batches of iPSC-derived cardiac fibroblasts. Data are expressed as mean ± SEM***p < 0.001 by non parametric t test. B: The protein expression levels of pyruvate kinase (muscular isoform-PKM), pyruvate kinase (L/R isoform), lactate dehydrogenase A and B, were quantified in iPSC-derived cardiac fibroblasts by western blotting and normalized to beta tubulin. Data are expressed as mean ± SEM of replicates of the six biological samples. C: Quantification of Intracellular l-lactate in iPSC-derived cardiac fibroblasts. Data are presented in mean ± SEM of replicates of the six biological samples, performed independently on different differentiation batches. ***p < 0.001 by non parametric t test. D: RT-PCR analysis of glucose transporter 1 mRNA expression levels. **p < 0.01 by non parametric t-test. E: Western blot analysis of phosphorylation on serine 293 of the PDH-E1α subunit in iPSC-derived cardiac fibroblasts.Data are presented in mean ± SEM of replicates of the six biological samples, performed independently on different differentiation batches