[Exendin-4 ameliorates high glucose- and TNF-α-induced vascular endothelial cell damage by inhibiting p38 MAPK and NF-κB p65 translocation].
ABSTRACT To investigate the protective effects of exendin-4 on vascular endothelial cells and explore the possible mechanism.
Human umbilical vascular endothelial cells (HUVECs) were cultured in the presence of high glucose and tumor necrosis factor-α (TNF-α, 10 ng/ml) with or without exendin-4. The level of nitric oxide (NO) in the cell culture supernatant was measured using a nitrate reductase method. The expression of intercellular adhesion molecule-1 (ICAM-1) mRNA was measured by real-time PCR, and nuclear factor-κB (NF-κB) p65 translocation was detected using immunofluorescence assay. Western blotting was employed to measure the expression of p38 MAPK protein in the treated cells.
In the presence of high glucose and TNF-α, treatment of cells with exendin-4 did not obviously affect the cellular synthesis of NO, but significantly down-regulated the expression of ICAM-1 mRNA (P<0.01). The nuclear fluorescence intensity of NF-κB p65 and the expression level of p38 MAPK protein in the cells were significantly lowered by exendin-4 treatment (P<0.01).
Exendin-4 ameliorates high glucose- and TNF-α-induced HUVEC-12 cell damage by inhibiting the expression of p38 MAPK protein and translocation of NF-κB p65.