Effect of MKP5 deletion in bone-marrow-derived macrophages on gene expression during oxidized-LDL stimulation

MKP-5 is a MAP kinase phosphatase that is responsible for the dephosphorylation of MAP kinases p-38 MAPK, JNK, and sometimes ERK. MKP-5 has been implicated in many diseases and its deletion results in increased inflammation. However, MKP-5 expression and regulation have not been studied in atherosclerosis, and our project aims to identify MKP-5 as a relevant gene in this disease. Specifically, we aim to identify the role of MKP-5 in the regulation of plaque stability. In atherosclerotic diseased states, oxidized LDL particles promote inflammatory mechanisms and form macrophage foam cells. We show that comparing wild-type and MKP-5-/- bone-marrow-derived macrophages stimulated with oxidized-LDL, results in the identification of significant gene expressions and major up- and down-regulated targeted pathways via bulk-RNA sequencing. Taken together, our data provides an unbiased way to test the mechanistic role of MKP-5 in an atherogenic environment. Furthermore, our data confirms and contributes to the current knowledge of gene expression influenced by MKP-5, as well as the influence of MKP-5 deletion on pathways critical to plaque stability including inflammation and collagen synthesis and deposition. To investigate the effect of MKP5 deletion on gene expression and major targeted pathways, bone marrow-derived macrophages (BMDMs) were isolated from the femurs of WT and MKP-5-/- mice and differentiated during a 7-day culture period with BMDM growth media containing 15% of L-929 supernatant. WT and MKP-5-/- BMDMs were then stimulated with ox-LDL (20µg/mL) for 0hr and 24hrs and collected at the respective end time point. Samples were then processed for RNA isolation and sent for bulk RNA seq using 1ug of RNA per sample.