In vivo and in vitro Approaches Reveal Novel Insight Into the Ability of Epicardium-Derived Cells to Create Their Own Extracellular Environment

Noortje A M Bax; Sjoerd N Duim; Boudewijn P T Kruithof; Anke M Smits; Carlijn V C Bouten; Marie José Goumans

doi:10.3389/fcvm.2019.00081

In vivo and in vitro Approaches Reveal Novel Insight Into the Ability of Epicardium-Derived Cells to Create Their Own Extracellular Environment

Front Cardiovasc Med. 2019 Jun 19:6:81. doi: 10.3389/fcvm.2019.00081. eCollection 2019.

Authors

Noortje A M Bax^{1

2

3}, Sjoerd N Duim^{1

2}, Boudewijn P T Kruithof¹, Anke M Smits¹, Carlijn V C Bouten^{2

3}, Marie José Goumans¹

Affiliations

¹ Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands.
² Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands.
³ Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, Netherlands.

Abstract

Human epicardium-derived cells (hEPDCs) transplanted in the NOD-SCID mouse heart after myocardial infarction (MI) are known to improve cardiac function, most likely orchestrated by paracrine mechanisms that limit adverse remodeling. It is not yet known, however, if hEPDCs contribute to preservation of cardiac function via the secretion of matrix proteins and/or matrix proteases to reduce scar formation. This study describes the ability of hEPDCs to produce human collagen type I after transplantation into the infarct border zone, thereby creating their own extracellular environment. As the in vivo environment is too complex to investigate the mechanisms involved, we use an in vitro set-up, mimicking biophysical and biochemical cues from the myocardial tissue to unravel hEPDC-induced matrix remodeling. The in vivo contribution of hEPDCs to the cardiac extracellular matrix (ECM) was assessed in a historical dataset of the NOD-SCID murine model of experimentally induced MI and cell transplantation. Analysis showed that within 48 h after transplantation, hEPDCs produce human collagen type I. The build-up of the human collagen microenvironment was reversed within 6 weeks. To understand the hEPDCs response to the pathologic cardiac microenvironment, we studied the influence of cyclic straining and/or transforming growth beta (TGFβ) signaling in vitro. We revealed that 48 h of cyclic straining induced collagen type I production via the TGFβ/ALK5 signaling pathway. The in vitro approach enables further unraveling of the hEPDCs ability to secrete matrix proteins and matrix proteases and the potential to create and remodel the cardiac matrix in response to injury.

Keywords: cardiac fibrosis; cardiac remodeling; cardiac repair; epicardium-derived cells; extracellular matrix (ECM); mechanosensitivity.