Figure 5.

Heat map analysis of metabolite levels in PPARα^+/+ and PPARα^−/− mice. a) Heat map summary of the genotype effect on fasting and fed state metabolite levels in plasma (plsm), liver (liv), and gastrocnemius muscle (skm) was generated using data from PPARα^−/− mice expressed relative to wild-type animals in the same condition, such that metabolites elevated in PPARα^−/− mice are red and depressed metabolites are green. Plasma organic acid profiles were not measured. Heat map representations of the pairwise correlation matrix were generated using plasma metabolites and muscle organic acids measured in the fed and fasted states in PPARα^+/+ (b) and PPARα^−/− (c) mice. Each square represents the Pearson correlation coefficient between the metabolite of the column with that of the row. Metabolite order was determined by supervised clustering based on biochemical classification. This analysis revealed genotype-specific patterning of several hot spots, indicative of strong positive (red) or negative (blue) correlations. AC, acylcarnitines; OA, organic acid/TCA cycle intermediates; carn, carnitine; aKG, alpha ketoglutarate; NEFA, nonesterified fatty acids; ala, alanine; glu, glutamate/glutamine; gly, glycine; his, histidine; pro, proline; met, methionine; ser, serine; val, valine; asp, aspartate/asparagine; arg, arginine; cit, citrulline; orn, ornitine; leu/ile, leucine/isoleucine; phe, phenylalanine; tyr, tyrosine; sum pls LCAC, sum of plasma long chain acylcarnitines from C14 to C22.