Figure 15.

Effect of the cysteine aminotransferase (CAT) inhibitor aspartate on H₂S production and function of isolated rat liver mitochondria. Rat liver mitochondria were isolated and studied as described (Módis et al., 2013b). In part (A) mitochondrial homogenates were subjected to H₂S measurements using the methylene blue method in the presence or absence of α-ketoglutarate (0.5 mM), aspartate (2 mM) and L-cysteine (1 mM) and their combinations; in parts (B-D), bioenergetic analysis was performed using the Extracellular Flux Analyzer (Seahorse) in the presence or absence of α-ketoglutarate (0.5 mM), aspartate (2 mM) and L-cysteine (10 μM) and their combinations. Please note that L-cysteine stimulated H₂S production and mitochondrial function, while the CAT inhibitor aspartate inhibited these responses. Data represent mean ± SEM of three experiments; *P < 0.05. The animal experimentation component of the studies was conducted with the approval of the Animal Care and Use Committee (IACUC) of the University of Texas Medical Branch and according to the applicable guidelines of the National Institute of Health.