Figure 2.

Bioenergetics of PSC-derived myogenic progenitors and re-isolated donor-derived satellite cells. (A) Outline of experiments. (B) Typical traces of real-time OCR before and after the addition of inhibitors to derive several parameters of mitochondrial respiration in Pax3 in vitro, iPax3 in vivo, and adult satellite cells (SC). (C) Initially, basal O₂ consumption OCR was measured, from which basal cellular respiration can be derived by subtracting non-mitochondrial respiration. (D) ATP-linked represent the difference in OCR before and after Oligomycin. (E) H+ leak-linked OCR in Pax3 in vitro, iPax3 in vivo, and adult SC represent the difference in OCR after Oligomycin injection and Antimycin A and Rotenone. (F) Maximal OCR was determined via addition of a mitochondrial uncoupler CCCP that stimulates maximal respiration by mimicking a physiological energy demand, leading to an increase in oxygen consumption. (G) Spare respiratory capacity OCR reflects the difference between basal and maximal respiratory rate, and this capacity was determined by measuring OCR after treatment with oligomycin and CCCP. (H) Real-time whole-cell extracellular acidification rate (ECAR) is an indicator of the rate of acid efflux formed during glycolytic energy metabolism used to generate ATP. (I) ECAR quantification in iPax3 in vitro, iPax3 in vivo, and adult SC. (J) Non-mitochondrial respiration OCR has been observed at low levels in iPax3 in vivo and Adult SC. (K) Graphs shows gene expression for Sdhd, Cox6b2, Atp5c1, and gapdh. Results are normalized to Actb. Data are presented as mean ± SEM (n = three biological samples per group). * p < 0.05, ** p < 0.01, and *** p < 0.001 from one-way ANOVA followed by post hoc Tukey.