Rapamycin Inhibits Ox-LDL-Induced Inflammation In HUVECs Via MTORC2/PKC/c-Fos Pathway

Objective:We aimed to observe the effects of rapamycin on ox-LDL-induced inflammation in HUVECs, and further reveal the potential mechanism.Methods: Ox-LDL was used to stimulate and induce inflammatory responses in HUVECs.Western blot was applied to examine the protein expression of ICAM-1 and E-selectin. The adhesion of macrophages to endothelial cells was detected by adhesion assay. m TOR, m TORC1, m TORC2 and c-Fos transfection were used to knockdown m TOR, m TORC1, m TORC2 and c-Fos respectively. PKC inhibitor staurosporine was used to inhibit PKC activity and PKC activator PMA/TPA was used to activate PKC activity. The expressions of m TOR, m TORC1, m TORC2, PKC, p-PKC, c-jun, p-c-jun and c-Fos were assayed by western blot analysis.Results:Western blot showed that rapamycin ameliorated ox-LDL-induced ICAM-1 and E-selectin expression. Adhesion assay showed that rapamycin alleviated ox-LDL-induced adhesion of macrophages to endothelial monolayer. m TOR si RNA could reduce ox-LDL-induced ICAM-1 and E-selectin expression and macrophages adhesion to HUVECs. m TORC2 si RNA reduced ox-LDL-induced ICAM-1 and E-selectin expression and macrophages adhesion to HUVECs while m TORC1 si RNA has not signifiant effect. The PKC inhibitor suppressed the protein expression of ICAM-1 and E-selectin and the adhesion of macrophages to endothelial cells in ox-LDL-treated cells. The PKC activator attenuated the inhibitory effect of rapamycin on ICAM-1 and E-selectin expression. c-Fos si RNA reduced ox-LDL-induced ICAM-1 and E-selectin expression and macrophages adhesion to HUVECs.Conclusions:Rapamycin reduces ox-LDL-stimulated adhesion molecules expression in HUVECs and macrophages adhesion to HUVECs by inhibiting m TORC2, and m TORC2 acts via PKC/c-Fos signaling pathway.