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Y it was reported that the PPAR/ agonist GW501516 stimulated human

by Dewitt Haveman (2021-02-27)

Y it was reported that the PPAR/ agonist GW501516 stimulated human umbilical vein endothelial cell (HUVECs) proliferation dose-dependently [9], promoted endothelial tube formation, and increased angiogenesis [8]. Another PPAR/ agonist, PubMed ID: GW0742, or muscle-specific overexpression of PPAR/, also promoted angiogenesis in mouse skeletal muscle [15]. Additional evidence further suggested that PPAR/ is one of the important TFs participating in the angiogenic network in endothelial cells [16,17]. These lines of evidence are strongly suggestive of a role for PPAR/ in angiogenesis. Although several key TFs have been shown to be involved in angiogenesis, the detailed underlying hierarchical or mutual interaction of multiple cascades is only partially understood [16]. To dissect the molecular mechanism of crosstalk in angiogenesis, we selected two important angiogenic stimuli, hypoxia and PPAR/ agonist stimulation, and investigated the molecular mechanism by which these two signals in concert are able to enhance a common angiogenesis-related target gene. In this study, we are focusing on the new molecular mechanism where conformational change could contribute to the co-operative transcriptional regulation of a common target by two different TFs. It was previously reported that synergistic transcription could be achieved by different TFs through enhanceosomes [18,19], which are complexes made from proteins binding to regulatory elements of genes. Apart from the enhansceosome concept, which emphasizes the diversity of TF specificity, our Rp-cAMPS findings on synergistic transcription suggest that chromatin structural changes are inseparable from the transcription machinery.crosstalk of these angiogenic stimuli in endothelial cells, we applied PPAR/ and hypoxia to HUVECs and studied the effect on cellular migration function by using a monolayer-wound healing assay. Figure 1A shows the distribution of the cells before and after the stimuli. Quantification of the endothelial cell migratory area (the red area in Figure 1A) is shown in Figure 1B. To avoid the effect of VEGF in the media, the assay was performed using endothelial culture media without any growth factors or fetal bovine serum (FBS). PPAR/ and hypoxia individually tended to be associated with greater recovery in HUVECS PubMed ID: than normoxia and DMSO, but this was not statistically significant. However, simultaneous application of both stimuli resulted in a significant increase in migration of endothelial cells compared to untreated control. This finding suggested that this experimental motif could be applied to elucidate the synergistic activation that is exerted through PPAR/ and HIF1 in endothelial cell function. Therefore, we focused on dissecting the molecular mechanism underlying the synergistic effect of the two stimuli.Genome-wide analysis of PPAR/ and/or hypoxiainduced genes in endothelial cells identified ANGPTL4 as the common target geneResultsEndothelial cell migration is synergistically enhanced by hypoxic and PPAR/ agonist stimuliTo confirm the physiological effect of hypoxia and the PPAR/ agonists, and to evaluate the physiologicalTo estimate the possible interaction of the PPAR/ and HIF1 signaling pathways in a more comprehensive manner, we performed transcriptome analysis using microarrays after 24 hours of treatment with a PPAR/-selective agonist (GW501516, 100 nM) and/or hypoxic (1 O2) stimulation. After normalization and filtering, gene expression change against the normoxia-DMSO sample wa.