Cardiac Differentiation Of Embryonic Stem Cells Research Articles

Butyric and Retinoic Mixed Ester of Hyaluronan: A NOVEL DIFFERENTIATING GLYCOCONJUGATE AFFORDING A HIGH THROUGHPUT OF CARDIOGENESIS IN EMBRYONIC STEM CELLS

Embryonic stem (ES) cells can differentiate into specialized cells, including cardiac myocytes, but the efficiency is typically low and the process is incompletely understood. Achieving a high throughput of cardiogenesis from pluripotent cells is therefore a major requirement for future approaches in cardiac cell therapy. Here, we developed a novel ester of hyaluronan linked to both butyric and retinoic acid (HBR), coaxing pluripotent ES cells into a cardiogenic decision. In mouse ES cells, HBR remarkably increased the expression of GATA-4 and Nkx-2.5, acting as cardiac lineage-promoting genes in different animal species, including humans. HBR also enhanced prodynorphin gene expression and the synthesis and secretion of dynorphin B, an endorphin playing a major role in ES cell cardiogenesis. These effects occurred at the transcriptional level. HBR also primed the expression of cardiac-specific transcripts and highly enhanced the yield of spontaneously beating ES-derived cardiomyocytes. These results demonstrate the potential for chemically modifying the gene program of cardiac differentiation in ES cells without the aid of gene transfer technologies and may pave the way for novel approaches in tissue engineering and myocardial regeneration.

Ascorbic acid enhances differentiation of embryonic stem cells into cardiac myocytes.

Embryonic stem (ES) cells are capable of self-renewal and differentiation into cellular derivatives of all 3 germ layers. In appropriate culture conditions, ES cells can differentiate into specialized cells, including cardiac myocytes, but the efficiency is typically low and the process is incompletely understood. We evaluated a chemical library for its potential to induce cardiac differentiation of ES cells in the absence of embryoid body formation. Using ES cells stably transfected with cardiac-specific alpha-cardiac myosin heavy chain (MHC) promoter-driven enhanced green fluorescent protein (EGFP), 880 compounds approved for human use were screened for their ability to induce cardiac differentiation. Treatment with ascorbic acid, also known as vitamin C, markedly increased the number of EGFP-positive cells, which displayed spontaneous and rhythmic contractile activity and stained positively for sarcomeric myosin and alpha-actinin. Furthermore, ascorbic acid induced the expression of cardiac genes, including GATA4, alpha-MHC, and beta-MHC in untransfected ES cells in a developmentally controlled manner. This effect of ascorbic acid on cardiac differentiation was not mimicked by the other antioxidants such as N-acetylcysteine, Tiron, or vitamin E. Ascorbic acid induces cardiac differentiation in ES cells. This study demonstrates the potential for chemically modifying the cardiac differentiation program of ES cells.