Delivery of biotinylated IGF-1 with biotinylated self-assembling peptides combined with bone marrow stem cell transplantation promotes cell therapy for myocardial infarction

Cell therapy is a promising approach for cardiac repair. The aim of the present study was to determine the feasibility of using biotinylated insulin-like growth factor 1 (IGF-1) with biotinylated self-assembling peptides (tethered IGF-1) combined with bone marrow stem cells (BMSCs) transplantation for the treatment of heart failure. Tethered IGF-1 was synthesized and its effect on H9c2 cells was analyzed. Reverse transcription-quantitative polymerase chain reaction and western blot assays demonstrated that tethered IGF-1 did not significantly affect the expression and phosphorylation of AKT, whereas it significantly increased the expression of cardiac troponin T (P<0.01). A rabbit myocardial infarction model was constructed and rabbits were divided into four groups: Control group (no treatment), group 1 (G1; BMSC transplantation), group 2 (G2; BMSCs + non-biotinylated IGF-1) and group 3 (G3; BMSCs + tethered IGF-1). At 4 weeks after modeling, cardiac tissues were obtained for analysis. In the control group, myocardial fibers were disordered, a large number of inflammatory cells infiltrated the cardiac tissues, and apoptosis occurred in ~50% of cells. However, in G1, G2 and G3, muscle cells were well ordered, and a lesser degree of myocardial degeneration and inflammatory cell infiltration was observed. Compared with the control group, the apoptosis rates of myocardial cells in G1-G3 were significantly decreased (P<0.01). Furthermore, compared with G1 and G2, tissue morphology was improved in G3and the number of apoptotic myocardial cells was significantly decreased (P<0.01). These results suggest that treatment with tethered IGF-1 + BMSCs significantly suppresses cell apoptosis and induces the expression of cardiac maturation proteins. These findings provide a novel insight into how the delivery of tethered IGF-1 with BMSCs could potentially enhance the prognosis of patients with heart failure treatment.