Fig. 1

The expression levels of WWP2 in vascular endothelial cells decline during T2DM. A Dot plot showing expression levels of genes in the KEGG apoptosis pathway in ECs of healthy control and T2DM donors (grey represent not significant). A total of 1,939 ECs were extracted from mesenteric arterial cells from 2 healthy control and 1 T2DM male donors. B Violin plots showing gene expression levels of WWP2 in ECs of T2DM patients and healthy controls. C Feature plots showing the percentage of cells expressing WWP2 in ECs of T2DM patients (28.1%) and healthy controls (17.3%). D Representative co-immunofluorescent staining for TUNEL (red; a marker of apoptosis) and CD31 (green; a marker of ECs) in aortic cross sections from control or T2DM wild-type mice (n = 3 mice per group). scale bar 50 µm. E Quantification of apoptotic ECs in CD31 positive cells. F Representative co-immunofluorescent staining for WWP2 (red) and CD31 (green) in aortic cross sections from control or T2DM wild-type mice (n = 3 mice per group). scale bar 50 µm. G Quantitative analysis of relative fluorescence intensity of WWP2 in CD31 positive cells. H Cell Counting Kit-8 colorimetric assay was used to evaluate the effects of HG/PA treatment on the proliferation and viability of HUVECs. I, J Representative Flow cytometry analysis (I) and quantitative analysis (J) of HUVECs apoptosis induced by HG/PA. K, L Representative Western blots (K) and quantification (L) of WWP2, Cleaved PARP1 and Cleaved caspase-3 protein expression levels in HUVECs with or without HG/PA treatment. Values are shown as mean ± SD (**P < 0.01, ***P < 0.001, two-tailed unpaired Student t-tests). Ctrl, control; DAPI, 4′,6-diamidino-2-phenylindole; ECs, Endothelial cells; HG/PA, high glucose/palmitic acid; HUVECs, HUVECs, Human umbilical vein endothelial cells; KEGG, Kyoto Encyclopedia of Genes and Genomes; T2DM, Type 2 diabetes mellitus