Fig. 2

CRP treatment upregulates VEGF protein and production levels and promotes angiogenesis in ADSCs. a CRP increased VEGF but not HGF production as assessed by western blotting. Values were normalized to β-tubulin as a control, *p < 0.05 versus control. b CRP increased VEGF production dose and time dependently as assessed by ELISA, peak at CRP 25 μg/ml, *p < 0.05 versus control. c CRP-induced VEGF increased capillary tube formation in vitro. (C1) HUVECs formed tubes in basal medium; (C2) culturing of HUVECs in ADSC supernatant induced tube formation; (C3) CRP-treated ADSCs conditioned medium (CM) enhanced tube formation; (C4) CRP-treated basal medium slightly decreased the HUVEC tube formation; (C5) HUVECs formed tubes cultured in EGM as positive control; (C6) VEGF-neutralizing antibody in CRP-treated ADSC CM prevented HUVEC tube formation; (C7) representative histogram of tube length in different medium, *p < 0.05, **p < 0.01. d Mice were injected subcutaneously with Matrigel mixed with PBS, ADSCs, and CRP-pretreated ADSCs. At day 7, mice were sacrificed, explanted Matrigel plugs were excised and processed for H & E staining (upper bars 100 μm, lower bars 50 μm) and light microscope, and microvessel density was quantified by counting vessel structures containing erythrocytes. Representative histogram of tube length in different medium, *p < 0.05; data represent mean ± SEM (n = 3). Columns, mean; error bars, SEM. Results are representative of three independent experiments. CRP C-reactive protein, VEGF vascular endothelial growth factor, HGF hepatocyte growth factor, ADSC, adipose-derived stem cell, EGM endothelial growth medium, MSC mesenchymal stem cell