Angiotensin II induces EMMPRIN expression in THP-1 macrophages via the NF-κB pathway

BackgroundRecent studies on atherosclerosis showed that an inducer of MMPs, EMMPRIN, is highly expressed in human atheromas. This suggested the important role of EMMPRIN in the stability of atherosclerotic plaques. Angiotensin II, one of the main functional peptides in the renin–angiotensin system, is involved in the advancement of atherosclerosis. We evaluated the effect of angiotensin II on EMMPRIN expression in THP-1 macrophages, and postulated the potential mechanisms underlying its effects.Methods and resultsWe established THP-1 macrophages using PMA. The effect of angII on EMMPRIN expression in THP-1 macrophages was then investigated. Results from analyses of RT-PCR and western blotting showed that angII could upregulate EMMPRIN expression. This was mediated via the AT1R, but not the AT2R. The NF-κB inhibitor PDTC and P65 RNAi treatment could suppress the effect of angII on EMMPRIN, suggesting the involvement of the NF-κB pathway. A gelatin zymography assay showed that MMP-9 activity was related to EMMPRIN expression.ConclusionAngII upregulates the expression of EMMPRIN. NF-κB is the critical factor involved in the upregulation of EMMPRIN induced by angII.