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.