Fig. 7: PPARγ pathway is activated in VECs of hyperlipidemic mice and conserved in human aortic valves. | Nature Communications

Fig. 7: PPARγ pathway is activated in VECs of hyperlipidemic mice and conserved in human aortic valves.

From: Single-cell transcriptomics reveal cellular diversity of aortic valve and the immunomodulation by PPARγ during hyperlipidemia

Fig. 7

a Average expression map of genes in PPARγ regulon, produced by Single-Cell Regulatory Network Inference and Clustering (SCENIC), for each cluster of leukocytes, VECs, and VICs. b UMAP plot of VECs color-coded by the activity of PPARγ regulon. Gene set activity was calculated by SCENIC. AUC: area under curve. c Immunostaining of PPARγ (red) and endomucin (EMCN, EC marker, green) in aortic valve with sinus from normal (chow diet) and hyperlipidemic mice (Apoe−/− and Ldlr−/− mice, WD for 16 weeks) (n = 4). DAPI (blue) was used to stain nuclei. The graph represents the relative MFI of PPARγ in the VECs. Kruskal–Wallis test with post-hoc Dunn’s test was used. Scale bar: 30 μm. d UMAP plot of 41,326 single-cells derived from human aortic valve, colored by the clusters (left) and samples (right). e Average expression map of genes in PPARγ regulon for each cell cluster from human aortic valve. f Pro-inflammatory (top) and cell adhesion molecule (bottom) scores in non-targeting siRNA (NC) and PPARG targeting siRNA-treated (PPARG knockdown, KD) human VECs under no (NT) and oxLDL treatment conditions. Each score represents the average expression level of the genes, as shown in Fig. 7g (n = 3). Each box depicts the IQR and median of each score, whiskers indicate 1.5 times the IQR. p, two-sided T-test p-value. g Expression map of pro-inflammatory genes (top) and cell adhesion molecules (bottom). The expression of genes in all samples was scaled by z-transformation. h–j PPARγ IHC in human aortic valves (n = 7 for non-calcified, n = 5 for calcified). Representative image of PPARγ IHC (top) and H&E stain (bottom) (h), measurement of PPARγ+ cellular proportion in valvular cells (left) and VECs (right) (i) and the positive correlation between PPARγ+ VECs of non-calcified and the plasma levels of total cholesterol and LDL (j). For (i), two-sided Mann–Whitney test, and for (j), the Spearman correlation test were used. Scale bar: 40 μm (left), 20 μm (right). Image data are representative of three independent experiments unless otherwise stated. Data are presented as mean ± SD.

Back to article page