Abstract
OBJECTIVES: To investigate the role and mechanism of fibroblast growth factor (FGF) 19 in inflammation-induced injury of vascular endothelial cells caused by high glucose (HG). METHODS: Human umbilical vein endothelial cells (HUVECs) were randomly divided into four groups: control, HG, FGF19, and HG+FGF19 (n=3 each). The effect of different concentrations of glucose and/or FGF19 on HUVEC viability was assessed using the CCK8 assay. Flow cytometry was utilized to examine the impact of FGF19 on HUVEC apoptosis. Levels of interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), total superoxide dismutase (T-SOD), and malondialdehyde (MDA) were measured by ELISA. Real-time quantitative PCR and Western blotting were used to determine the mRNA and protein expression levels of vascular endothelial growth factor (VEGF), nuclear factor erythroid 2 related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). Cells were further divided into control, siRNA-Nrf2 (siNrf2), HG, HG+FGF19, HG+FGF19+negative control, and HG+FGF19+siNrf2 groups (n=3 each) to observe the effect of FGF19 on oxidative stress injury in HUVECs induced by high glucose after silencing the Nrf2 gene. RESULTS: Compared to the control group, the HG group exhibited increased apoptosis rate, increased IL-6, iNOS and MDA levels, and increased VEGF mRNA and protein expression, along with decreased T-SOD activity and decreased mRNA and protein expression of Nrf2 and HO-1 (P<0.05). Compared to the HG group, the HG+FGF19 group showed reduced apoptosis rate, decreased IL-6, iNOS and MDA levels, and decreased VEGF mRNA and protein expression, with increased T-SOD activity and increased Nrf2 and HO-1 mRNA and protein expression (P<0.05). Compared to the HG+FGF19+negative control group, the HG+FGF19+siNrf2 group had decreased T-SOD activity and increased MDA levels (P<0.05). CONCLUSIONS: FGF19 can alleviate inflammation-induced injury in vascular endothelial cells caused by HG, potentially through the Nrf2/HO-1 signaling pathway.