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bioRxiv · 10.1101/2023.03.06.531428

The novel coronary artery disease risk factor ADAMTS-7 modulates atherosclerotic plaque formation by degradation of TIMP-1

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Abstract

BackgroundThe ADAMTS7 locus was genome-wide significantly associated with coronary artery disease (CAD). Lack of the extracellular matrix (ECM) protease ADAMTS-7 was shown to reduce atherosclerotic plaque formation. ObjectiveTo identify molecular mechanisms and downstream targets of ADAMTS-7 mediating risk of atherosclerosis. MethodsTargets of ADAMTS-7 were identified by high-resolution mass spectrometry of atherosclerotic plaques from Apoe-/- and Apoe-/-Adamts7-/- mice. ECM proteins were identified using solubility profiling. Putative targets were validated using immunofluorescence, in vitro degradation assays, co-immunoprecipitation, and Forster resonance energy transfer (FRET)-based protein-protein interaction assays. ADAMTS7 expression was measured in fibrous caps of human carotid artery plaques. ResultsIn humans, ADAMTS7 expression was higher in caps of unstable as compared to stable carotid plaques. Compared to Apoe-/- mice, atherosclerotic aortas of Apoe-/- mice lacking Adamts-7 (Apoe-/-Adamts7-/-) contained higher protein levels of tissue inhibitor of metalloproteases 1 (Timp-1). In co-immunoprecipitation experiments, the catalytic domain of ADAMTS-7 bound to TIMP-1, which was degraded in the presence of ADAMTS-7 in vitro. ADAMTS-7 reduced the inhibitory capacity of TIMP-1 at its canonical target matrix metalloprotease 9 (MMP-9) As a downstream mechanism, we investigated collagen content in plaques of Apoe-/- and Apoe-/-Adamts7-/- mice after Western diet. Picrosirius red staining of the aortic root revealed less collagen as a readout of higher MMP-9 activity in Apoe-/- as compared to Apoe-/- Adamts7-/- mice. In order to facilitate high-throughput screening for ADAMTS-7 inhibitors with the aim to decrease TIMP-1 degradation, we designed a FRET-based assay targeting the ADAMTS-7 catalytic site. ConclusionADAMTS-7, which is induced in unstable atherosclerotic plaques, decreases TIMP-1 stability reducing its inhibitory effect on MMP-9, which is known to promote collagen degradation and is likewise genome-wide significantly associated with CAD. Disrupting the interaction of ADAMTS-7 and TIMP-1 might be a strategy to increase collagen content and plaque stability for reduction of atherosclerosis-related events.

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Sharifi, A., Wierer, M., Dang, T. A., Milic, J., Moggio, A., Sachs, N., von Scheidt, M., Hinterdobler, J., Müller, P., Werner, J., Stiller, B., Aherrahrou, Z., Erdmann, J., Zaliani, A., Graettinger, M., Reinshagen, J., Gul, S., Gribbon, P., Maegdefessel, L., Bernhagen, J., Sager, H. B., Mann, M., Schunkert, H., Kessler, T.. 2023-03-08. The novel coronary artery disease risk factor ADAMTS-7 modulates atherosclerotic plaque formation by degradation of TIMP-1. https://doi.org/10.1101/2023.03.06.531428

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