ADAMTS-7 Modulates Atherosclerotic Plaque Formation by Degradation of TIMP-1

Circ Res. 2023 Sep 29;133(8):674-686. doi: 10.1161/CIRCRESAHA.123.322737. Epub 2023 Sep 7.

Abstract

Background: The ADAMTS7 locus was genome-wide significantly associated with coronary artery disease. Lack of the ECM (extracellular matrix) protease ADAMTS-7 (A disintegrin and metalloproteinase-7) was shown to reduce atherosclerotic plaque formation. Here, we sought to identify molecular mechanisms and downstream targets of ADAMTS-7 mediating the risk of atherosclerosis.

Methods: Targets 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, coimmunoprecipitation, and Förster resonance energy transfer-based protein-protein interaction assays. ADAMTS7 expression was measured in fibrous caps of human carotid artery plaques.

Results: In 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 Timp-1 (tissue inhibitor of metalloprotease-1). In coimmunoprecipitation 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 MMP-9 (matrix metalloprotease-9). As a downstream mechanism, we investigated collagen content in plaques of Apoe-/- and Apoe-/-Adamts7-/- mice after a 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. To facilitate high-throughput screening for ADAMTS-7 inhibitors with the aim of decreasing TIMP-1 degradation, we designed a Förster resonance energy transfer-based assay targeting the ADAMTS-7 catalytic site.

Conclusions: ADAMTS-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 associated with coronary artery disease. Disrupting the interaction of ADAMTS-7 and TIMP-1 might be a strategy to increase collagen content and plaque stability for the reduction of atherosclerosis-related events.

Keywords: aorta; atherosclerosis; disintegrins; mice; solubility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ADAMTS7 Protein* / genetics
  • Animals
  • Atherosclerosis* / genetics
  • Collagen / metabolism
  • Coronary Artery Disease* / genetics
  • Humans
  • Matrix Metalloproteinase 9
  • Mice
  • Mice, Knockout, ApoE
  • Plaque, Atherosclerotic* / metabolism
  • Tissue Inhibitor of Metalloproteinase-1* / genetics
  • Tissue Inhibitor of Metalloproteinase-1* / metabolism

Substances

  • ADAMTS7 Protein
  • Collagen
  • Matrix Metalloproteinase 9
  • Tissue Inhibitor of Metalloproteinase-1
  • ADAMTS7 protein, human
  • Adamts7 protein, mouse