Original article
Angiotensin II induced proteolytic cleavage of myocardial ACE2 is mediated by TACE/ADAM-17: A positive feedback mechanism in the RAS
Graphical abstract
Introduction
The renin–angiotensin system (RAS) is a central regulator of the cardiovascular system and plays a fundamental role in the pathophysiology of experimental and human heart failure (HF) [1], [2], [3]. RAS consists of two counter-regulatory arms regulating cardiovascular function. The first arm consists of a series of enzymatic reactions culminating in the generation of angiotensin II (Ang II) which can lead to Ang II type 1 receptor (AT1R) dependent vasoconstriction, inflammation, myocardial fibrosis and hypertrophy and HF [1], [4]. The second arm is constituted by the angiotensin converting enzyme (ACE) 2/Ang 1–7/Mas receptor axis which acts as a physiological antagonist of the ACE/Ang II/AT1R arm [5], [6]. ACE2 as a negative regulator of the RAS, functions to promote the degradation of Ang II into the vasodilator, anti-hypertrophic, and anti-inflammatory heptapeptide, Ang 1–7 [7], [8], [9].
ACE inhibitors and AT1 receptor blockers have revolutionized the treatment of HF and reduce the morbidity and mortality in patients with HF. Interestingly, these drugs also increased myocardial ACE2 levels and activity [10]. Loss of ACE2 is detrimental to the heart as it leads to cardiac hypertrophy and impaired contractility due in part to increased Ang II stimulation of AT1R [8], [9], [11], [12], whereas ACE2 over-expression protects the heart from Ang II-mediated cardiac hypertrophy and myocardial fibrosis [9], [13]. ACE2 is a type I transmembrane protein, with an extracellular N-terminal domain containing the active site [5], [6]. Proteolysis on the cell surface and in the extracellular matrix is an important mechanism leading to cancer, inflammatory and cardiovascular diseases [14], [15], [16]. In this study, we showed that Ang II triggered the cleavage and shedding of a soluble form of ACE2 from the membrane by TNFα-converting enzyme (TACE), also known as a disintegrin and metalloproteinase (ADAM) 17. Ang II-stimulated and TACE-mediated loss of myocardial ACE2 orchestrates a critical link between the RAS, oxidative stress and inflammation in heart disease and represents the first description of a positive feedback mechanism in the RAS.
Section snippets
Experimental animals and protocols
Mice lacking p47phox (p47phoxKO; p47phox −/−) backcrossed into a pure C57BL/6 background were used as previously described [17]. Only C57BL/6 male wild-type (WT) controls were used. An osmotic minipump (model 1002, Alzet Osmotic Pumps, Cupertino, CA) was implanted subcutaneously at the dorsum of the neck to continuously infuse Ang II (1.5 mg/kg/day) or saline (vehicle) for 1 week or 2 weeks. TACEflox/flox mice [18] were crossed with the cardiac-specific α-MHC-Cre transgenic mice to create
Ang II mediates loss of ACE2 with upregulation of TACE/ADAM-17 in the heart: a key role of the AT1R receptor
Western blot analysis showed a marked reduction in heart ACE2 in response to 1 and 2 weeks of in vivo exposure to elevated Ang II (Fig. 1A) with a marked increase in Ace2 mRNA levels (Fig. 1B). Ang II-mediated loss of ACE2 levels was clearly suppressed by AT1R blockade (Fig. 1C) which was mirrored by the assessment of ACE2 activity (Fig. 1D) with reciprocal changes seen in plasma ACE2 activity (Fig. 1E). However, AT1R blockade did not alter the Ang II induced upregulation of Ace2 mRNA expression
Discussion
The RAS plays a central role in the pathophysiology of many cardiovascular diseases and suppression of the ACE/Ang II/AT1R axis of the RAS minimizes cardiovascular complications. ACE2/Ang 1–7/Mas receptor is the counter regulatory axis of the RAS where ACE2 serves as an endogenous negative regulator of the RAS and reduces Ang II levels and increases the generation of Ang 1–7 [7], [8], [9], [11], [12], [33]. We showed that Ang II mediates loss of ACE2 in the heart. Myocardial ACE2 level in
Conflict of interest statement
Vaibhav B. Patel: None.
Nicola Clarke: None.
Zuocheng Wang: None.
Dong Fan: None.
Nirmal Parajuli: None.
Ratnadeep Basu: None.
Brendan Putko: None.
Zamaneh Kassiri: None.
Anthony Turner: None.
Gavin Y. Oudit: None.
Acknowledgments
GYO is a Clinician-Investigator of the Alberta Innovates—Health Solutions (AI-HS) and the Distinguish Clinician Scientist of the Heart and Stroke Foundation of Canada and Canadian Institutes of Health Research (CIHR). ZK is a New Investigator of the Heart and Stroke Foundation of Canada (HSFC) and Scholar of the AI-HS. VBP is supported by AI-HS Post-Doctoral Fellowship and VBP and NP are supported by Heart and Stroke Foundation of Canada Fellowships. We acknowledge the funding support from CIHR
References (43)
- et al.
A human homolog of angiotensin-converting enzyme. Cloning and functional expression as a captopril-insensitive carboxypeptidase
J Biol Chem
(2000) Regulation of the proteolytic disintegrin metalloproteinases, the ‘Sheddases’
Semin Cell Dev Biol
(2009)- et al.
The many faces of metalloproteases: cell growth, invasion, angiogenesis and metastasis
Trends Cell Biol
(2001) - et al.
Detection of soluble angiotensin-converting enzyme 2 in heart failure: insights into the endogenous counter-regulatory pathway of the renin–angiotensin–aldosterone system
J Am Coll Cardiol
(2008) - et al.
Direct activation of TACE-mediated ectodomain shedding by p38 MAP kinase regulates EGF receptor-dependent cell proliferation
Mol Cell
(2010) - et al.
Tumor necrosis factor-alpha convertase (ADAM17) mediates regulated ectodomain shedding of the severe-acute respiratory syndrome-coronavirus (SARS-CoV) receptor, angiotensin-converting enzyme-2 (ACE2)
J Biol Chem
(2005) - et al.
Calmodulin interacts with angiotensin-converting enzyme-2 (ACE2) and inhibits shedding of its ectodomain
FEBS Lett
(2008) - et al.
Reactive oxygen species and p38 mitogen-activated protein kinase mediate tumor necrosis factor alpha-converting enzyme (TACE/ADAM-17) activation in primary human monocytes
J Biol Chem
(2011) - et al.
Distinct ADAM metalloproteinases regulate G protein-coupled receptor-induced cell proliferation and survival
J Biol Chem
(2004) - et al.
Soluble angiotensin-converting enzyme 2 in human heart failure: relation with myocardial function and clinical outcomes
J Card Fail
(2009)
Effects of renin–angiotensin system blockade on renal angiotensin-(1–7) forming enzymes and receptors
Kidney Int
Angiotensin II cell signaling: physiological and pathological effects in the cardiovascular system
Am J Physiol Cell Physiol
Hormones regulating cardiovascular function in patients with severe congestive heart failure and their relation to mortality. CONSENSUS Trial Study Group
Circulation
Cardiac angiotensin II formation in the clinical course of heart failure and its relationship with left ventricular function
Circ Res
Translational success stories: angiotensin receptor 1 antagonists in heart failure
Circ Res
A novel angiotensin-converting enzyme-related carboxypeptidase (ACE2) converts angiotensin I to angiotensin 1–9
Circ Res
Angiotensin-converting enzyme 2 is an essential regulator of heart function
Nature
Loss of angiotensin-converting enzyme-2 exacerbates diabetic cardiovascular complications and leads to systolic and vascular dysfunction: a critical role of the angiotensin II/AT1 receptor axis
Circ Res
Angiotensin-converting enzyme 2 suppresses pathological hypertrophy, myocardial fibrosis, and cardiac dysfunction
Circulation
Effect of angiotensin-converting enzyme inhibition and angiotensin II receptor blockers on cardiac angiotensin-converting enzyme 2
Circulation
Loss of angiotensin-converting enzyme 2 accelerates maladaptive left ventricular remodeling in response to myocardial infarction
Circ Heart Fail
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