Genetic background-independent increases in phenylalanine and tryptophan metabolites in an ALD mouse model. Urinary excretion of indole-3-lactic acid in (a) wild-type and (b) Ppara-null mice on the B6 background. Urinary excretion of phenyllactic acid in (c) wild-type and (d) Ppara-null mice on the B6 background. Urinary excretion of phenyllactic acid in (e) wild-type and (f) Ppara-null mice on the 129S background. Dashed and solid lines represent control and alcoholic diet-treated mice, respectively. (One-way ANOVA with Bonferroni’s correction for multiple comparisons, significance at P < 0.05 with ‡, significantly different from Ppara-null mice of same treatment group; #, significantly different from control mice of same genotype; *, significantly different from alcohol-treated wild-type mice)