Recombinant proteins secreted from tissue-engineered bioartificial muscle improve cardiac dysfunction and suppress cardiomyocyte apoptosis in rats with heart failure

• Published in: Chinese medical journal 2010-12, Vol.123 (24), p.3626-3633
• Main Authors: Rong, Shu-Ling, Wang, Yong-Jin, Wang, Xiao-Lin, Lu, Yong-Xin, Wu, Yin, Liu, Qi-Yun, Mi, Shao-Hua, Xu, Yu-Lan
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis; Caspase 3 - analysis; Desmin - analysis; Genetic Therapy; Heart Failure - pathology; Heart Failure - physiopathology; Heart Failure - therapy; Insulin-Like Growth Factor I - genetics; Insulin-Like Growth Factor I - secretion; Myoblasts, Skeletal - metabolism; Myocytes, Cardiac - pathology; Rats; Rats, Sprague-Dawley; Recombinant Proteins - secretion; Retroviridae - genetics; Tissue Engineering; Tumor Necrosis Factor-alpha - analysis; Ventricular Function, Left; 人工肌肉; 心力衰竭; 心肌细胞凋亡; 组织工程化; 胰岛素样生长因子-1; 蛋白分泌; 重组蛋白
• ISSN: 0366-6999; 2542-5641
• DOI: 10.3760/cma.j.issn.0366-6999.2010.24.022

Background Tissue-engineered bioartificial muscle-based gene therapy represents a promising approach for the treatment of heart diseases. Experimental and clinical studies suggest that systemic administration of insulin-like growth factor-1 （IGF-1） protein or overexpression of IGF-1 in the heart exerts a favorable effect on cardiovascular function. This study aimed to investigate a chronic stage after myocardial infarction （MI） and the potential therapeutic effects of delivering a human IGF-1 gene by tissue-engineered bioartificial muscles （BAMs） following coronary artery ligation in Sprague-Dawley rats.Methods Ligation of the left coronary artery or sham operation was performed. Primary skeletal myoblasts were retrovirally transduced to synthesize and secrete recombinant human insulin-like growth factor-1 （rhIGF-1）, and green fluorescent protein （GFP）, and tissue-engineered into implantable BAMs. The rats that underwent ligation were randomly assigned to 2 groups： MI-IGF group （n=6） and MI-GFP group （n=6）. The MI-IGF group received rhIGF-secreting BAM （IGF-BAMs） transplantation, and the MI-GFP group received GFP-secreting BAM （GFP-BAMs） transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups： S-IGF group （n=6）and S-GFP group （n=6）. The S-IGF group underwent IGF-1-BAM transplantation, and S-GFP group underwent GFP-BAM transplantation. IGF-1-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats after two weeks of operation was performed. Four weeks after the treatment, hemodynamics was performed. IGF-1 was measured by radioimmunoassay, and then the rats were sacrificed and ventricular samples were subjected to immunohistochemistry. Reverse transcriptase-polymerase chain reaction （RT-PCR） was used to examine the mRNA expression of bax and Bcl-2. TNF-α and caspase 3 expression in myocardium was examined by Western blotting.Results Primary rat myoblasts were retrovirally transduced to secrete rhlGF-1 and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted consistent levels of hIGF （0.4-1.2 μg·BAM-1·d-1）. When implanted into syngeneic rat, IGF-BAMs secreted and delivered rhIGF. Four weeks after therapy,the hemodynamics was improved significantly in MI rats treated with IGF-BAMs compared with those treated with GFP-BAMs. The levels of serum IGF-1 were increased significantly in both MI and sham rats treated with IGF-BA