Pseudomonas aeruginosa Planktonic- and Biofilm-Conditioned Media Elicit Discrete Metabolic Responses in Human Macrophages

Macrophages (M phi s) are prevalent innate immune cells, present throughout human bodily tissues where they orchestrate innate and adaptive immune responses to maintain cellular homeostasis. M phi s have the capacity to display a wide array of functional phenotypes due to different microenvironmental cues, particularly soluble bacterial secretory products. Recent evidence has emerged demonstrating that metabolism supports M phi function and plasticity, in addition to energy and biomolecular precursor production. In this study, 1D H-1-NMR-based metabolomics was used to identify the metabolic pathways that are differentially altered following primary human monocyte-derived M phi exposure to P. aeruginosa planktonic- and biofilm-conditioned media (PCM and BCM). Metabolic profiling of PCM- and BCM-exposed M phi s indicated a significant increase in glycolytic metabolism, purine biosynthesis, and inositol phosphate metabolism. In addition, these metabolic patterns suggested that BCM-exposed M phi s exhibit a hyperinflammatory metabolic profile with reduced glycerol metabolism and elevated catabolism of lactate and amino acids, relative to PCM-exposed M phi s. Altogether, our study reveals novel findings concerning the metabolic modulation of human M phi s after exposure to secretory microbial products and contributes additional knowledge to the field of immunometabolism in M phi s.