Figure 4.

Examples of in vivo spectra following [2-¹³C]pyruvate (A and B) and [1-¹³C]αKG (C) injections with individual metabolite fitting lines. (A): [2-¹³C]pyruvate (orange), [2-¹³C]pyruvate-hydrate (blue), and [2-¹³C]lactate (yellow). (B): [5-¹³C]glutamate (red), [5-¹³C]glutamine (navy), [1-¹³C]acetoacetate (light blue), [1-¹³C]acetylcarnitine (green), [1-¹³C]pyruvate (purple), and residual signal (above). Note that Figure 4B shows the fitting result after excluding [2-¹³C]pyruvate to enable phasing of all metabolite. (C): [5-¹³C]α-ketoglutarate + [1-¹³C]2-hydroxyglutarate (yellow), [1-¹³C]α-ketoglutarate-hydrate (blue), [1-¹³C]glutamate (purple), [1-¹³C]α-ketoglutarate (orange), and residual signal (above).