Abstract
Cardiovascular diseases account for more deaths than any other illness. Cardiac tissue engineering has turned to embryonic stem cells as a renewable source of myocytes for use in tissue replacement. Existing methods for stem cell differentiation toward the cardiac lineage are relatively non-specific, yielding low numbers of myocytes with varying contraction frequencies and strengths. Here we describe novel experimental approaches, utilizing an electrical stimulation regimen, aimed at increasing the efficiency of cardiac differentiation from mouse embryonic stem (mES) cells. These methods generate cardiac myocytes with functional characteristics that more closely resemble native tissues. The amplitude, duration, and frequency of the electrical stimulus as well as the timing of its onset are some of the critical experimental parameters that determine the enhancement of cardiac differentiation. In order to form embryoid bodies, an optimum differentiation regime was followed incorporating the hanging drop method followed by suspension culture and subsequent post-plating on conductive slides with electrical stimulation. Approximately three times more stimulated mES cells exhibited evidence of cardiac differentiation than their non-stimulated counterparts, as determined by the expression of ventricular marker myosin light chain-2v. Spontaneous contractions of the stimulated cell populations began up to 1 day earlier and had an average beat frequency close to that of the stimulus applied during differentiation. The spontaneously contracting regions had larger areas of contraction, which beat more rhythmically, as determined by real-time digital imaging analysis. Our results suggest that appropriate electrical stimulation generates greater numbers of more robust cardiac myocytes, which in turn may be better suited for repairing or regenerating an ailing heart and for use as 3D model systems for drug discovery.
Original language | English |
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Title of host publication | Stem Cell Engineering |
Subtitle of host publication | Principles and Applications |
Publisher | Springer Berlin Heidelberg |
Pages | 119-141 |
Number of pages | 23 |
ISBN (Print) | 9783642118647 |
DOIs | |
State | Published - 2011 |
Externally published | Yes |
Keywords
- Cardiac differentiation
- Conductive surfaces
- Electrical stimulation
- Indium-Tin-Oxide
- Mouse embryonic stem cells
- Multi-Electrode Assembly
- Myosin light chain-2v
- Optical Recording