First Author | Song B | Year | 2013 |
Journal | Circ J | Volume | 77 |
Issue | 12 | Pages | 2997-3006 |
PubMed ID | 24161906 | Mgi Jnum | J:286409 |
Mgi Id | MGI:6403548 | Doi | 10.1253/circj.CJ-13-0805 |
Citation | Song B, et al. (2013) Loss of angiotensin-converting enzyme 2 exacerbates myocardial injury via activation of the CTGF-fractalkine signaling pathway. Circ J 77(12):2997-3006 |
abstractText | BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) has been implicated in human heart failure, but the mechanism remains elusive. We hypothesized that ACE2 deficiency would exacerbate angiotensin (Ang) II-mediated myocardial injury. METHODS AND RESULTS: 10-week-old ACE2 knockout (ACE2KO) and wild-type mice received by mini-osmotic pump either AngII (1.5 mg.kg(-1).day(-1)) or saline for 2 weeks. ACE2 deficiency triggered greater increases in the expression of connective tissue growth factor (CTGF), fractalkine (FKN) and phosphorylated ERK1/2 in AngII-treated ACE2KO hearts. These changes were associated with greater activation of matrix metalloproteinase (MMP) 2, MMP9 and MT1-MMP and exacerbation of myocardial injury and dysfunction. In cultured cardiofibroblasts, exposure to AngII (100 nmol/L) for 30 min resulted in marked increases in superoxide production and expression of CTGF, FKN and phosphorylated ERK1/2, which were strikingly prevented by recombinant human ACE2 (rhACE2; 1mg/ml) and the CTGF-neutralizing antibody (5 mug/ml), but were aggravated by ACE2 inhibitor DX600 (0.5 mumol/L). These protective effects of rhACE2 were eradicated by the Ang-(1-7) antagonist A779 (1 mumol/L). More intriguingly, rhACE2 treatment significantly abolished AngII-mediated increases in MMP2, MMP9 and MT1-MMP in cardiofibroblasts. CONCLUSIONS: Loss of ACE2 exacerbates AngII-mediated inflammation, myocardial injury and dysfunction in ACE2-deficient hearts via activation of the CTGF-FKN-ERK and MMP signaling. ACE2 gene may represent a potential candidate to prevent and treat myocardial injury and heart diseases. |