Effect of TGF-B1 on primary human lung fibroblasts growing in media with physiological glucose and glutamine
The interplay between metabolism and gene expression is primarily known through epigenetic modifications which use metabolites such as acetyl-CoA. Glucose and glutamine are critical for the synthesis of these metabolites but the concentrations of these two major nutrients are not standardized in conventional tissue culture media. The aim of this study was to investigate the transcriptomic effect of TGF-B1 after 24 hours in primary human lung fibroblasts (pHLFs) growing in DMEM with glucose and glutamine set at physiological concentrations (5 and 0.7 mM, respectively). We were then able to compare these gene  expression patterns to a previously published dataset of pHLFs growing in DMEM with higher concentrations of glucose and glutamine (25 and 2 mM, respectively) (GSE102674). This revealed a dramatic difference of roughly 3-fold differentially expressed genes dependent on DMEM formulation as well as just half of the top 20 enriched pathways induced by TGF-B1 shared, as analysed with GSEA. The conclusion was that the concentrations of glucose and glutamine have profound effects on gene expression changes. Overall design: Primary human lung fibroblasts were treated with TGFß1 for 24h in DMEM with 5mM glucose and 0.7mM glutamine. Each treatment was done in triplicate, for a total of 6 samples. Untreated cells were used as control. Paired-end RNA sequencing was performed with the NextSeq sequencing platform (Illumina, San Diego, CA, USA). Each sample was run on 4 different lanes.