Modulation of human embryonic stem cell-derived cardiomyocyte growth: a testbed for studying human cardiac hypertrophy?
Human embryonic stem cell-derived cardiomyocytes (hESC-CM) are being developed for tissue repair and as a model system for cardiac physiology and pathophysiology. However, the signaling requirements of their growth have not yet been fully characterized. We showed that hESC-CM retain their capacity for increase in size in long-term culture. Exposing hESC-CM to hypertrophic stimuli such as equiaxial cyclic stretch, angiotensin II, and phenylephrine (PE) increased cell size and volume, percentage of hESC-CM with organized sarcomeres, levels of ANF, and cytoskeletal assembly. PE effects on cell size were separable from those on cell cycle. Changes in cell size by PE were completely inhibited by p38-MAPK, calcineurin/FKBP, and mTOR blockers. p38-MAPK and calcineurin were also implicated in basal cell growth. Inhibitors of ERK, JNK, and CaMK II partially reduced PE effects; PKG or GSK3β inhibitors had no effect. The role of p38-MAPK was confirmed by an additional pharmacological inhibitor and adenoviral infection of hESC-CM with a dominant-inhibitory form of p38-MAPK. Infection of hESC-CM with constitutively active upstream MAP2K3b resulted in an increased cell size, sarcomere and cytoskeletal assembly, elongation of the cells, and induction of ANF mRNA levels. siRNA knockdown of p38-MAPK inhibited PE-induced effects on cell size. These results reveal an important role for active protein kinase signaling in hESC-CM growth and hypertrophy, with potential implications for hESC-CM as a novel in vitro test system. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".
National Heart and Lung Institute, Imperial College London, London, UK. g.foldes@imperial.ac.uk
Gábor
G
Földes
Maxime
M
Mioulane
Jamie S
JS
Wright
Alexander Q
AQ
Liu
Pavel
P
Novak
Béla
B
Merkely
Julia
J
Gorelik
Michael D
MD
Schneider
Nadire N
NN
Ali
Sian E
SE
Harding
D000804:Angiotensin II / Q000494:pharmacology; D006332:Cardiomegaly / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology*; D002453:Cell Cycle / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000166:cytology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D048371:MAP Kinase Kinase 3 / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D010656:Phenylephrine / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors
D047428:Protein Kinase Inhibitors; D014662:Vasoconstrictor Agents; D000804:Angiotensin II; D010656:Phenylephrine; D048051:p38 Mitogen-Activated Protein Kinases; D048371:MAP Kinase Kinase 3; C482530:MAP2K3 protein, human