title: Hydrogel-based engineered skeletal muscle grafts normalize heart function early after myocardial infarction.
abstract: Tissue engineering represents an attractive approach for the treatment of congestive heart failure. The influence of the differentiation of myogenic graft for functional recovery is not defined. We engineered a biodegradable skeletal muscle graft (ESMG) tissue and investigated its functional effect after implantation on the epicardium of an infarcted heart segment. ESMGs were synthesized by mixing collagen (2 mg/mL), Matrigel (2 mg/mL), and rat skeletal muscle cells (10(6)). Qualitative and quantitative aspects of ESMGs were optimized. Two weeks following coronary ligation, the animals were randomized in three groups: ESMG glued to the epicardial surface with fibrin (ESMG, n = 7), fibrin alone (fibrin, n = 5), or sham operation (sham, n = 4). Echocardiography, histology, and immunostaining were performed 4 weeks later. A cohesive three-dimensional tissular structure formed in vitro within 1 week. Myoblasts differentiated into randomly oriented myotubes. Four weeks postimplantation, ESMGs were vascularized and invaded by granulation tissue. Mean fractional shortening (FS) was, however, significantly increased in the ESMG group as compared with preimplantation values (42 +/- 6 vs. 33 +/- 5%, P < 0.05) and reached the values of controlled noninfarcted animals (control, n = 5; 45 +/- 3%; not significant). Pre- and postimplantation FS did not change over these 4 weeks in the sham group and the fibrin-treated animals. This study showed that it is possible to improve systolic heart function following myocardial infarction through implantation of differentiated muscle fibers seeded on a gel-type scaffold despite a low rate of survival.
authors.affiliation: Department of Cardiovascular Surgery, Inselspital, Berne, Switzerland. giraud@dkf.unibe.ch
authors.forename: Marie-Noëlle
authors.initials: MN
authors.lastname: Giraud
authors.forename: Erick
authors.initials: E
authors.lastname: Ayuni
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cook
authors.forename: Matthias
authors.initials: M
authors.lastname: Siepe
authors.forename: Thierry P
authors.initials: TP
authors.lastname: Carrel
authors.forename: Hendrik T
authors.initials: HT
authors.lastname: Tevaearai
mesh_terms: D000818:Animals; D064987:Cell- and Tissue-Based Therapy / Q000379:methods; D003094:Collagen / Q000138:chemical synthesis; D004338:Drug Combinations; D005260:Female; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000138:chemical synthesis / Q000494:pharmacology*; D007797:Laminin / Q000138:chemical synthesis; D018485:Muscle Fibers, Skeletal; D018482:Muscle, Skeletal / Q000166:cytology / Q000254:growth & development / Q000637:transplantation*; D032448:Myoblasts, Skeletal / Q000166:cytology / Q000637:transplantation; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D011509:Proteoglycans / Q000138:chemical synthesis; D011897:Random Allocation; D051381:Rats; D046509:Tissue Culture Techniques / Q000379:methods; D019737:Transplants; D014463:Ultrasonography
chemical_list: D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D003094:Collagen