Activation of peroxisome proliferator-activated receptor alpha in human peripheral blood mononuclear cells reveals an individual gene expression profile response

Background: Peripheral blood mononuclear cells (PBMCs) are relatively easily obtainable cells in humans. Gene expression profiles of PBMCs have been shown to reflect the pathological and physiological state of a person. Recently, we showed that the nuclear receptor peroxisome proliferator-activated receptor alpha (PPAR alpha) has a functional role in human PBMCs during fasting. However, the extent of the role of PPAR alpha in human PBMCs remains unclear. In this study, we therefore performed gene expression profiling of PBMCs incubated with the specific PPAR alpha ligand WY 14,643. Results: Incubation of PBMCs with WY 14,643 for 12 hours resulted in a differential expression of 1,373 of the 13,080 genes expressed in the PBMCs. Gene expression profiles showed a clear individual response to PPAR alpha activation between six healthy human blood donors. Pathway analysis showed that genes in fatty acid metabolism, primarily in beta-oxidation were up-regulated upon activation of PPAR alpha with WY14,643, and genes in several amino acid metabolism pathways were down-regulated. Conclusion: This study shows that PPAR alpha in human PBMCs regulates fatty acid and amino acid metabolism. In addition, PBMC gene expression profiles show individual responses to WY14,643 activation. We showed that PBMCs are a suitable model to study changes in PPAR alpha activation in healthy humans.