Effects of Intracoronary Infusion of Escalating Doses of Cardiac Stem Cells in Rats With Acute Myocardial Infarction.
Circ Heart Fail
; 8(4): 757-65, 2015 Jul.
Article
em En
| MEDLINE
| ID: mdl-25995227
ABSTRACT
BACKGROUND:
Although c-kit(pos) cardiac stem cells (CSCs) preserve left ventricular (LV) function and structure after myocardial infarction, CSC doses have been chosen arbitrarily, and the dose-effect relationship is unknown. METHODS ANDRESULTS:
Rats underwent a 90-minute coronary occlusion followed by 35 days of reperfusion. Vehicle or CSCs at 5 escalating doses (0.3×10(6), 0.75×10(6), 1.5×10(6), 3.0×10(6), and 6.0×10(6) cells/heart) were given intracoronarily 4 h after reperfusion. The lowest dose (0.3×10(6)) had no effect on LV function and morphology, whereas 0.75, 1.5, and 3.0×10(6) significantly improved regional and global LV function (echocardiography and hemodynamic studies). These 3 doses had similar effects on echocardiographic parameters (infarct wall thickening fraction, LV end-systolic and end-diastolic volumes, LV ejection fraction) and hemodynamic variables (LV end-diastolic pressure, LV dP/dtmax, preload adjusted maximal power, end-systolic elastance, preload recruitable stroke work) and produced similar reductions in apoptosis, scar size, infarct wall thinning, and LV expansion index and similar increases in viable myocardium in the risk region (morphometry). Infusion of 6.0×10(6) CSCs markedly increased postprocedural mortality. Green fluorescent protein and 5-bromo-2'-deoxyuridine staining indicated that persistence of donor cells and formation of new myocytes were negligible with all doses.CONCLUSIONS:
Surprisingly, in this rat model of acute myocardial infarction, the dose-response relationship for intracoronary CSCs is flat. A minimal dose between 0.3 and 0.75×10(6) is necessary for efficacy; above this threshold, a 4-fold increase in cell number does not produce greater improvement in LV function or structure. Further increases in cell dose are harmful.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regeneração
/
Função Ventricular Esquerda
/
Miócitos Cardíacos
/
Transplante de Células-Tronco
/
Infarto do Miocárdio
/
Miocárdio
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Circ Heart Fail
Assunto da revista:
ANGIOLOGIA
/
CARDIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article