The ability to analyze genome-wide gene expression through “transcriptomics” has shown that the genome responds dynamically to diverse stimuli. We described the transcriptome of human vascular smooth muscle cells (hVSMC) stimulated by native and oxidized low-density lipoprotein (nLDL and oxLDL respectively), with the aim of assessing the early molecular changes that induce a response in this cell type resulting in a transcriptomic transformation. This expression has been demonstrated in atherosclerotic plaques in vivo and in vitro, particularly in the light of the oxidative modification hypothesis of atherosclerosis.
The transcriptome of hVSMC under different experimental conditions (1,5 and 24 hours for nLDL and ox-LDL) was obtained using the GeneChip Human Gene 1.0 ST designed to measure the gene expression of 28,869 well-annotated genes. A fixed fold-change cut-off corresponding to ± 2 was used to identify genes exhibiting the most significant variation and statistical significance (P< 0.05), and 8 genes validated by qPCR using Taqman probes. 10 molecular processes were affected significantly: Apoptosis and cell cycle, extracellular matrix remodeling, DNA repair, cholesterol efflux,cGMP biosynthesis, endocytic mechanisms, calcium homeostasis, redox balance, membrane trafficking and finally immune response to inflammation related genes. The evidence presented support the oxidative modification hypothesis of atherosclerosisis.
Hierarchical cluster analysis of different receptors and their expression with the six experimental conditions (N1h, N5h, N24h, Ox1h, Ox5h, Ox24h) compared to parental VSMC cells.