To determine whether the altered transcripts induced by HDAC inhibition led to altered metabolic pathways in lupus mice, we examined the enzyme activity of proteins involved in electron transport chain function, the tricarboxylic acid cycle, and fatty acid beta oxidation in the spleens of lupus mice treated with the HDAC6 inhibitor ACY-728 for a 4-week period (Figure 7). The gene discussed is HDAC9; the disease is systemic lupus erythematosus.