Angiotensin (1-7) ameliorates the structural and biochemical alterations of ovariectomy-induced osteoporosis in rats via activation of ACE-2/Mas receptor axis

Sci Rep. 2017 May 23;7(1):2293. doi: 10.1038/s41598-017-02570-x.

Abstract

The local and systemic renin angiotensin system (RAS) influences the skeletal system micro-structure and metabolism. Studies suggested angiotensin 1-7 (Ang(1-7)) as the beneficial RAS molecule via Mas receptor activation. This study examines the function of Ang(1-7) in bone micro-architecture and metabolism in an ovariectomized (OVX) rodent model of osteoporosis. OVX rats showed structural and bone metabolic degeneration in parallel with suppressed expressions of the angiotensin converting enzyme-2 (ACE-2)/Ang(1-7)/Mas components. The infusion of Ang(1-7) markedly alleviated the altered bone metabolism and significantly enhanced both trabecular (metaphyseal) and cortical (metaphyseal-diaphyseal) morphometry. Urinary and bones minerals were also improved in OVX rats by Ang(1-7). The infusion of the heptapeptide enhanced ACE-2/Mas receptor expressions, while down-regulated AngII, ACE, and AngII type-1 receptor (AT1R) in OVX animals. Moreover, Ang(1-7) markedly improved osteoprotegerin (OPG) and lowered receptor activator NF-κB ligand (RANKL) expressions. The defensive properties of Ang(1-7) on bone metabolism, structure and minerals were considerably eradicated after blockage of Mas receptor with A-779. Ang(1-7)-induced up-regulated ACE-2/Ang(1-7)/Mas cascade and OPG expressions were abolished and the expressions of ACE/AngII/AT1R and RANKL were provoked by A-779. These findings shows for the first time the novel valuable therapeutic role of Ang(1-7) on bone health and metabolism through the ACE-2/Mas cascade.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin I / pharmacology*
  • Angiotensin-Converting Enzyme 2
  • Animals
  • Blotting, Western
  • Female
  • Humans
  • Organ Size / drug effects
  • Osteoporosis / etiology
  • Osteoporosis / metabolism
  • Osteoporosis / prevention & control*
  • Osteoprotegerin / metabolism
  • Ovariectomy / adverse effects*
  • Peptide Fragments / pharmacology*
  • Peptidyl-Dipeptidase A / metabolism*
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins / metabolism*
  • RANK Ligand / metabolism
  • Rats, Wistar
  • Receptors, G-Protein-Coupled / metabolism*
  • Signal Transduction / drug effects
  • Uterus / drug effects
  • Uterus / pathology

Substances

  • Osteoprotegerin
  • Peptide Fragments
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins
  • RANK Ligand
  • Receptors, G-Protein-Coupled
  • Angiotensin I
  • Peptidyl-Dipeptidase A
  • ACE2 protein, human
  • Ace2 protein, rat
  • Angiotensin-Converting Enzyme 2
  • angiotensin I (1-7)