ADAMTS16 activates latent TGF-β, accentuating fibrosis and dysfunction of the pressure-overloaded heart

Abstract

Aims Cardiac fibrosis is a major cause of heart failure (HF), and mediated by the differentiation of cardiac fibroblasts into myofibroblasts. However, limited tools are available to block cardiac fibrosis. ADAMTS16 is a member of the ADAMTS superfamily of extracellular protease enzymes involved in extracellular matrix (ECM) degradation and remodelling. In this study, we aimed to establish ADAMTS16 as a key regulator of cardiac fibrosis. Methods and results Western blot and qRT–PCR analyses demonstrated that ADAMTS16 was significantly up-regulated in mice with transverse aortic constriction (TAC) associated with left ventricular hypertrophy and HF, which was correlated with increased expression of Mmp2, Mmp9, Col1a1, and Col3a1. Overexpression of ADAMTS16 accelerated the AngII-induced activation of cardiac fibroblasts into myofibroblasts. Protein structural analysis and co-immunoprecipitation revealed that ADAMTS16 interacted with the latency-associated peptide (LAP)-transforming growth factor (TGF)-β via a RRFR motif. Overexpression of ADAMTS16 induced the activation of TGF-β in cardiac fibroblasts; however, the effects were blocked by a mutation of the RRFR motif to IIFI, knockdown of Adamts16 expression, or a TGF-β-neutralizing antibody (ΝAb). The RRFR tetrapeptide, but not control IIFI peptide, blocked the interaction between ADAMTS16 and LAP-TGF-β, and accelerated the activation of TGF-β in cardiac fibroblasts. In TAC mice, the RRFR tetrapeptide aggravated cardiac fibrosis and hypertrophy by up-regulation of ECM proteins, activation of TGF-β, and increased SMAD2/SMAD3 signalling, however, the effects were blocked by TGF-β-NAb. Conclusion ADAMTS16 promotes cardiac fibrosis, cardiac hypertrophy, and HF by facilitating cardiac fibroblasts activation via interacting with and activating LAP-TGF-β signalling. The RRFR motif of ADAMTS16 disrupts the interaction between ADAMTS16 and LAP-TGF-β, activates TGF-β, and aggravated cardiac fibrosis and hypertrophy. This study identifies a novel regulator of TGF-β signalling and cardiac fibrosis, and provides a new target for the development of therapeutic treatment of cardiac fibrosis and HF.

Transforming growth factor–β in tissue fibrosis

“…Depending on contextual factors, the type of injury, and the cell biological composition of the tissue, several different pathways may play a role in TGF-β activation in fibrotic tissues. First, a number of proteases, including calpains, cathepsins, serine proteases, matrix metalloproteinases (MMPs), and members of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family, are capable of activating TGF-β in vitro and may be implicated in TGF-β activation in fibrotic lesions in vivo ( Shea et al, 2017 ; Briassouli et al, 2011 ; Bourd-Boittin et al, 2011 ; Edgtton et al, 2004 ; Okuno et al, 2001 ; Khalil et al, 1996 ; Yao et al, 2019 ). Considering the promiscuity of these proteases, which are capable of interacting with numerous substrates, the relative significance of their TGF-β–activating effects remains poorly understood.…”

The C-Mannosylome of Human Induced Pluripotent Stem Cells Implies a Role for ADAMTS16 C-Mannosylation in Eye Development

“…Thus, ADAMTS16 was suggested to be involved in degradation of the basement membrane at the optic fissure edges, the prerequisite for optic fissure closure ( 44 ). ADAMTS16 was further shown to be an activator of the latent transforming growth factor-β signaling ( 55 ). Concerted regulation of the transforming growth factor-β signaling pathway is crucial for embryonic development, as for instance for the morphogenesis of the eye ( 56 , 57 ).…”

Risk Prediction Model Based on Biomarkers of Remodeling in Patients with Acute Anterior ST-Segment Elevation Myocardial Infarction

“…Hein et al found that expression of TGF-β was closely related to the degree of myocardial fibrosis in patients with compensatory cardiac hypertrophy that progressed to heart failure [ 22 ]. Studies on animal models have shown that TGF-β overexpression causes interstitial fibrosis and cardiac hypertrophy [ 23 ]. A consensus from an international forum on cardiac remodeling noted that elevated LVEDV and decreased LVEF occur in post-infarction LVR [ 24 ].…”