Developmental origin of postnatal cardiomyogenic progenitor cells.

Yuan-Hung Liu,Jiunn-Lee Lin,Chih-Jen Chou,Yi-Shuan Lin,Shinn-Chih Wu,Ling-Ping Lai,Shih-Yun Huang

doi:10.4155/fsoa-2016-0006

Abstract

Aim:To trace the cell origin of the cells involved in postnatal cardiomyogenesis.Materials & methods:Nkx2.5 enhancer-eGFP (Nkx2.5 enh-eGFP) mice were used to test the cardiomyogenic potential of Nkx2.5 enhancer-expressing cells. By analyzing Cre excision of activated Nkx2.5-eGFP+ cells from different lineage-Cre/Nkx2.5 enh-eGFP/ROSA26 reporter mice, we traced the developmental origin of Nkx2.5 enhancer-expressing cells.Results:Nkx2.5 enhancer-expressing cells could differentiate into striated cardiomyocytes both in vitro and in vivo. Nkx2.5-eGFP+ cells increased remarkably after experimental myocardial infarction (MI). The post-MI Nkx2.5-eGFP+ cells originated from the embryonic epicardial cells, not from the pre-existing cardiomyocytes, endothelial cells, cardiac neural crest cells or perinatal/postnatal epicardial cells.Conclusion:Postnatal Nkx2.5 enhancer-expressing cells are cardiomyogenic progenitor cells and originate from embryonic epicardium-derived cells.

Highlights

The external and internal parts of the heart were obtained by digesting the whole heart with collagenase for 1 h and the myocardial part was obtained from trituration and digestion of the remaining heart tissue
Because studies in zebrafish have shown that cardiac injury activates the epicardial cell layer and initiates cardiac regeneration at the subepicardial layer [27,28], differential gene expression analysis was performed
Using inducible Nkx2.5 enhCre/R26R-LacZ mice [20] to lineage trace postnatal Nkx2.5 enhancer-expressing cells, we confirmed that Nkx2.5 enhancer-expressing cells contribute directly to postnatal cardiomyogenesis after myocardial injury

Summary

Objectives

To trace the cell origin of the cells involved in postnatal cardiomyogenesis. The aim of this study was to determine if the postnatal Nkx2.5 enhancer expressing cells are cardiomyogenic progenitor cells and to trace the developmental origin of these progenitor cells.

Methods

Results

Discussion

Conclusion