Endothelial TBK1 Deficiency Inhibits Endothelial-to-Mesenchymal Transition and Atherogenesis Through Suppressing PAK1/ERK1/2 Signaling.

BACKGROUND: Atherosclerotic vascular diseases remain the leading cause of death despite the use of lipid-lowering drugs. The development of more efficacious therapies targeting endothelial inflammation and endothelial-to-mesenchymal transition (EndMT) is an essential endeavor, aiming for better treatment outcomes. The increased mutation frequency of the METHODS: The results of liquid chromatography-mass spectrometry, immunostaining, RNA sequencing, and Western blot in mouse and human arteries with atherosclerotic plaques identified TBK1 as one of the key mediators of EndMT and atherogenesis. Its role was then investigated in endothelium-specific TBK1 knockdown RESULTS: An increased expression of TBK1 was observed by liquid chromatography-mass spectrometry analysis in the aortas of CONCLUSIONS: The interaction between activated TBK1 and PAK1IP1 inhibits the binding of PAK1IP1 to PAK1, which, in turn, increases the phosphorylation of PAK1 and ERK1/2 in endothelial cells. This process drives EndMT. Endothelium-specific TBK1 knockdown or GSK8612 treatment inhibits EndMT and plaque formation. Safe TBK1 inhibitors could be developed into effective agents for the treatment of atherosclerotic vascular disease.