Myocardial scaffold-based cardiac tissue engineering: application of coordinated mechanical and electrical stimulations.
Recently, we developed an optimal decellularization protocol to generate 3D porcine myocardial scaffolds, which preserve the natural extracellular matrix structure, mechanical anisotropy, and vasculature templates and also show good cell recellularization and differentiation potential. In this study, a multistimulation bioreactor was built to provide coordinated mechanical and electrical stimulation for facilitating stem cell differentiation and cardiac construct development. The acellular myocardial scaffolds were seeded with mesenchymal stem cells (10(6) cells/mL) by needle injection and subjected to 5-azacytidine treatment (3 μmol/L, 24 h) and various bioreactor conditioning protocols. We found that after 2 days of culturing with mechanical (20% strain) and electrical stimulation (5 V, 1 Hz), high cell density and good cell viability were observed in the reseeded scaffold. Immunofluorescence staining demonstrated that the differentiated cells showed a cardiomyocyte-like phenotype by expressing sarcomeric α-actinin, myosin heavy chain, cardiac troponin T, connexin-43, and N-cadherin. Biaxial mechanical testing demonstrated that positive tissue remodeling took place after 2 days of bioreactor conditioning (20% strain + 5 V, 1 Hz); passive mechanical properties of the 2 day and 4 day tissue constructs were comparable to those of the tissue constructs produced by stirring reseeding followed by 2 weeks of static culturing, implying the effectiveness and efficiency of the coordinated simulations in promoting tissue remodeling. In short, the synergistic stimulations might be beneficial not only for the quality of cardiac construct development but also for patients by reducing the waiting time in future clinical scenarios.
Tissue Bioengineering Laboratory, Department of Biological Engineering, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, USA.
Bo
B
Wang
Guangjun
G
Wang
Filip
F
To
J Ryan
JR
Butler
Andrew
A
Claude
Ronald M
RM
McLaughlin
Lakiesha N
LN
Williams
Amy L
AL
de Jongh Curry
Jun
J
Liao
D000185:Actinin / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001374:Azacitidine / Q000494:pharmacology; D015415:Biomarkers / Q000378:metabolism; D019149:Bioreactors; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002452:Cell Count; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival; D002478:Cells, Cultured; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D004558:Electric Stimulation; D005109:Extracellular Matrix / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D040542:Mechanotransduction, Cellular; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism; D051381:Rats; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D020107:Troponin T / Q000235:genetics / Q000378:metabolism
D015415:Biomarkers; D015820:Cadherins; D018031:Connexin 43; D020107:Troponin T; D000185:Actinin; D018995:Myosin Heavy Chains; D001374:Azacitidine