[TNF-α activates RhoA/ROCK signaling pathway and increases permeability of endothelial cells infected with Listeria monocytogenes].

Objective To investigate the role of Ras homolog gene (Rho) A/Rho-associated coiled-coil containing protein kinase (ROCK) signaling pathway in tumor necrosis factor α (TNF-α) promoting hyper-permeability of vascular endothelial cells infected by Listeria monocytogenes (Lm) . Methods The cultured human umbilical vein endothelial cells (HUVECs) were divided into a control group (uninfected cells), TNF-α treatment group (100 ng/mL TNF-α, for 2 hours), Lm infection group (infected with MOI=10 Lm for 2 hours, then added gentamicin for 0.5 hour), Lm infection and TNF-α treatment group (infected with Lm and then treated with 100 ng/mL TNF-α for 2 hours), and Y-27632 inhibitor group combined with Lm infection and TNF-α treatment (treated with 50 μmol/L ROCK inhibitor Y-27632 for 30 minutes, and then Lm infection and TNF-α treatment as above). The protein levels of RhoA, zonula occluden-1 (ZO-1), occludin and ROCK in HUVECs were detected by Western blot analysis; the permeability of HUVECs was analyzed by the horseradish peroxidase (HRP) leakage; and the distribution of F-actin in HUVECs was detected by fluorescein isothiocyanate (FITC)-labeled phalloidine staining. Results TNF-α reduced the expression of tight junction protein ZO-1 and occludin in Lm-infected HUVECs, promoted its hyper-permeability and cytoskeletal rearrangement, and up-regulated the expression of RhoA and ROCK. ROCK inhibitor Y-27632 obviously inhibited the cytoskeleton rearrangement and hyper-permeability of HUVECs induced by TNF-α. Conclusion TNF-α can enhance hyper-permeability of HUVECs infected by Lm, which may be regulated by RhoA/Rock signaling pathway.