bioRxiv Science⌕ Search

Biology subjects

Hinterdobler, J.

Publications and source records attributed to Hinterdobler, J..

2 recordsLinked to original sources

Cigarette smoking upregulates vascular expression of the novel atherosclerosis risk factor ADAMTS-7

BackgroundCigarette smoking is an established risk factor for coronary artery disease (CAD) and myocardial infarction. Genetic variants in the extracellular matrix protease ADAMTS-7 were also identified to increase CAD risk. Notably, ADAMTS7 represents the only genomic locus that revealed a gene-environment interaction with smoking. The underlying mechanisms of this interaction remain unclear. Methods and ResultsIn a murine model, cigarette smoke exposure (CSE) led to an upregulation of vascular ADAMTS7 expression in wild type (WT) C57BL/6J mice. ADAMTS7 upregulation was also found in carotid plaques from ever-smokers undergoing carotid endarterectomy in humans. Bulk RNA sequencing of lung tissues from WT mice exposed to CS revealed a downregulation of 20 and an upregulation of 173 transcripts. Among upregulated transcripts in smoking-exposed lungs, we found C-C motif chemokine ligand 17 (CCL17), which was likewise upregulated in plasma from smoking mice and humans. In vitro, recombinant CCL17 upregulated ADAMTS7 expression in primary vascular smooth muscle cells (VSMC), which was inhibited secondary to silencing of CCL17s bona fide receptor C-C Motif Chemokine Receptor 4 (CCR4). Conditioned media from CCL17-stimulated VSMC lacking ADAMTS-7 showed reduced release of inflammatory cytokines by endothelial cells (EC), reduced EC activation, and monocyte-to-EC adhesion. In proatherogenic Apoe-/- mice exposed to CS, more numerous neutrophils, inflammatory monocytes, and macrophages were found in atherosclerotic plaques as compared to room air exposition. This effect was blunted in Apoe-/-Adamts7-/- mice. ConclusionsFor the first time, our findings link CSE to vascular inflammation via CCL17-mediated upregulation of the CAD risk factor ADAMTS7 and provide a mechanistic explanation for the gene-environment interaction between CS and ADAMTS7 in CAD. Targeting ADAMTS-7 might be a promising therapeutic strategy irrespective of smoking status. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/685237v1_ufig1.gif" ALT="Figure 1"> View larger version (16K): org.highwire.dtl.DTLVardef@1d8366eorg.highwire.dtl.DTLVardef@1dda3feorg.highwire.dtl.DTLVardef@39a4bcorg.highwire.dtl.DTLVardef@6e58b6_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

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

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.

molecular biology↗