Loss of smooth muscle cell disintegrin and metalloproteinase 17 transiently suppresses angiotensin II-induced hypertension and end-organ damage

J Mol Cell Cardiol. 2017 Feb:103:11-21. doi: 10.1016/j.yjmcc.2016.12.001. Epub 2016 Dec 16.

Abstract

Hypertension is associated with hypertrophy and hyperplasia of smooth muscle cells (SMCs). Disintegrin and metalloproteinase 17 (ADAM17) is a membrane-bound enzyme reported to mediate SMC hypertrophy through activation of epidermal growth factor receptor (EGFR). We investigated the role of ADAM17 in Ang II-induced hypertension and end-organ damage. VSMC was isolated from mice with intact ADAM17 expression (Adam17f/f) or lacking ADAM17 in the SMC (Adam17f/f/CreSm22). Human VSMCs were isolated from the aorta of donors, and ADAM17 deletion was achieved by siRNA transfection. Ang II suppressed proliferation and migration of Adam17-deficient SMCs, but did not affect apoptosis (mouse and human), this was associated with reduced activation of EGFR and Erk1/2 signaling. Adam17f/f/CreSm22 and littermate Adam17f/f mice received saline or Ang II (Alzet pumps, 1.5mg/kg/d; 2 or 4weeks). Daily blood pressure measurement in conscious mice (telemetry) showed suppressed hypertension in Adam17f/f/CreSm22 mice during the first week of Ang II infusion, but by the second week, it become comparable to that in Adam17f/f mice. EGFR activation remained suppressed in Adam17f/f/CreSm22-Ang II arteries. Ex vivo vascular function and compliance assessed in mesenteric arteries were comparable between genotypes. Consistent with the transient protection against Ang II-induced hypertension, Adam17f/f/CreSm22 mice exhibited significantly lower cardiac hypertrophy and fibrosis, and renal fibrosis at 2weeks post-Ang II, however this protection was abolished by the fourth week of Ang II infusion. In conclusion, while Adam17-deficiency suppresses Ang II-induced SMC remodeling in vitro, in vivo Adam17-deficiency provides only a transient protective effect against Ang II-mediated hypertension and end-organ damage.

Keywords: A disintegrin and metalloproteinase 17 (ADAM17); Blood pressure; Cardiac hypertrophy; Fibrosis; Smooth muscle cells (SMCs).

MeSH terms

  • Angiotensin II / adverse effects
  • Angiotensin II / metabolism*
  • Animals
  • Apoptosis
  • Disease Models, Animal
  • Disintegrins / metabolism*
  • ErbB Receptors / metabolism
  • Humans
  • Hypertension / etiology*
  • Hypertension / metabolism*
  • Hypertension / pathology
  • Male
  • Matrix Metalloproteinase 17 / deficiency
  • Matrix Metalloproteinase 17 / genetics
  • Matrix Metalloproteinase 17 / metabolism*
  • Mice
  • Mice, Knockout
  • Muscle, Smooth, Vascular / metabolism
  • Myocytes, Smooth Muscle / metabolism*

Substances

  • Disintegrins
  • Angiotensin II
  • ErbB Receptors
  • Matrix Metalloproteinase 17