title: Mesenchymal Stem Cells Improve Heart Rate Variability and Baroreflex Sensitivity in Rats with Chronic Heart Failure.
abstract: Heart failure induced by myocardial infarct (MI) attenuates the heart rate variability (HRV) and baroreflex sensitivity, which are important risk factors for life-threatening cardiovascular events. Therapies with mesenchymal stem cells (MSCs) have shown promising results after MI. However, the effects of MSCs on hemodynamic (heart rate and arterial pressure) variability and baroreflex sensitivity in chronic heart failure (CHF) following MI have not been evaluated thus far. Male Wistar rats received MSCs or saline solution intravenously 1 week after ligation of the left coronary artery. Control (noninfarcted) rats were also evaluated. MI size was assessed using single-photon emission computed tomography (SPECT). The left ventricular ejection fraction (LVEF) was evaluated using radionuclide ventriculography. Four weeks after MSC injection, the animals were anesthetized and instrumented for chronic ECG recording and catheters were implanted in the femoral artery to record arterial pressure. Arterial pressure and HRVs were determined in time and frequency domain (spectral analysis) while HRV was also examined using nonlinear methods: DFA (detrended fluctuation analysis) and sample entropy. The initial MI size was the same among all infarcted rats but was reduced by MSCs. CHF rats exhibited increased myocardial interstitial collagen and sample entropy combined with the attenuation of the following cardiocirculatory parameters: DFA indices, LVEF, baroreflex sensitivity, and HRV. Nevertheless, MSCs hampered all these alterations, except the LVEF reduction. Therefore, 4 weeks after MSC therapy was applied to CHF rats, MI size and myocardial interstitial fibrosis decreased, while baroreflex sensitivity and HRV improved.
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Sharon Del Bem Velloso
authors.initials: Sdel B
authors.lastname: de Morais
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Luiz Eduardo Virgilio
authors.initials: LE
authors.lastname: da Silva
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Renata Maria
authors.initials: RM
authors.lastname: Lataro
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Carlos Alberto Aguiar
authors.initials: CA
authors.lastname: Silva
authors.affiliation: 2 Department of Internal Medicine, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Luciano Fonseca Lemos
authors.initials: LF
authors.lastname: de Oliveira
authors.affiliation: 2 Department of Internal Medicine, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Eduardo Elias Vieira
authors.initials: EE
authors.lastname: de Carvalho
authors.affiliation: 2 Department of Internal Medicine, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Marcus Vinicius
authors.initials: MV
authors.lastname: Simões
authors.affiliation: 3 Graduate Program in Cellular and Molecular Biology Applied to Health, Lutheran University of Brazil , Ribeirão Preto, Brazil .
authors.forename: Lindolfo
authors.initials: L
authors.lastname: da Silva Meirelles
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Rubens
authors.initials: R
authors.lastname: Fazan
authors.affiliation: 1 Department of Physiology, Medical School of Ribeirao Preto, University of Sao Paulo , Ribeirão Preto, Brazil .
authors.forename: Helio Cesar
authors.initials: HC
authors.lastname: Salgado
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000473:pathology / Q000628:therapy*; D062186:Arterial Pressure / Q000502:physiology; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; D064987:Cell- and Tissue-Based Therapy / Q000379:methods; D003331:Coronary Vessels / Q000601:surgery; D006333:Heart Failure / Q000473:pathology / Q000628:therapy*; D006339:Heart Rate / Q000502:physiology*; D006439:Hemodynamics; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology; D009203:Myocardial Infarction / Q000473:pathology; D015635:Radionuclide Ventriculography; D051381:Rats; D017208:Rats, Wistar; D013318:Stroke Volume / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology