Smooth muscle cell sheet transplantation preserve cardiac function and minimize cardiac remodeling in a rat myocardial infarction model

• Published in: Journal of cardiothoracic surgery Vol. 11; no. 1; p. 131
• Main Authors: Harada, Shingo, Nakamura, Yoshinobu, Shiraya, Suguru, Fujiwara, Yoshikazu, Kishimoto, Yuichiro, Onohara, Takeshi, Otsuki, Yuki, Kishimoto, Satoru, Yamamoto, Yasutaka, Hisatome, Ichiro, Nishimura, Motonobu
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 05-08-2016; BioMed Central
• Subjects: Animals; Apoptosis; Care and treatment; Cell Hypoxia - physiology; Cell transplantation; Cells, Cultured; Disease Models, Animal; Echocardiography; Fibroblast Growth Factor 2 - secretion; Fibroblasts - transplantation; Fibrosis; Health aspects; Heart attack; Male; Muscle cells; Muscle, Smooth, Vascular - cytology; Myocardial Infarction - physiopathology; Myocardial Infarction - surgery; Myocardium - pathology; Myocytes, Smooth Muscle - secretion; Myocytes, Smooth Muscle - transplantation; Physiological aspects; Rats; Skin - cytology; Smooth muscle; Ventricular Dysfunction, Left - diagnostic imaging; Ventricular Dysfunction, Left - physiopathology; Ventricular Remodeling; Japan; Myocardial infarction; Cell sheet; Cell survival; Smooth muscle cells
• ISSN: 1749-8090; 1749-8090
• DOI: 10.1186/s13019-016-0508-x

We examined whether a vascular smooth muscle cell (SMC) sheet is effective in the treatment of a rat myocardial infarction (MI) model.
We examined the effect of SMC sheet on the cardiac function and cardiac remodeling in a rat MI model in comparison with their effect of dermal fibroblast (DFB) sheet in vivo. Furthermore, we estimated the apoptosis and secretion of angiogenic factor of SMC under hypoxic condition in comparison with DFB. Seven days after MI, monolayer cell sheets were transplanted on the infarcted area (SMC transplantation group, SMC-Tx; DFB transplantation group, DFB-Tx; no cell sheet transplantation group, Untreated; neither MI nor cell sheet transplantation group, Sham). We evaluated cardiac function by echocardiogram, degree of cardiac remodeling by histological examination, and secretion of angiogenic growth factor by enzyme immunoassay.
Twenty-eight days after transplantation, SMC-Tx showed the following characteristics compared with the other groups: 1) significantly greater fractional area shortening (SMC-Tx, 32.3 ± 2.1 %; DFB-Tx, 23.3 ± 2.1 %; untreated, 25.1 ± 2.6 %), 2) suppressed left ventricular dilation, smaller scar expansion, and preserved wall thickness of the area at risk and the posterior wall, 3) decreased fibrosis, preserved myocardium in the scar area, and greater number of arterioles in border-zone, 4) tight attachment of SMC sheets on the scarred myocardium, and less apoptotic cell death. In in vitro experiments, SMCs secreted higher amounts of basic fibroblast growth factor (SMC, 157.7 ± 6.4 pg/ml; DFB, 3.1 ± 1.0 pg/ml), and showed less apoptotic cell death under hypoxia.
Our results illustrate that transplantation of SMC sheets inhibited the progression of cardiac remodeling and improve cardiac function. These beneficial effects may be due to superior SMC survival.