Mesenchymal-endothelial transition contributes to cardiac neovascularization

Area of Science:

• Cardiovascular Biology
• Cellular Biology
• Regenerative Medicine

Background:

• Endothelial cells are vital for blood vessel formation.
• Cardiac fibroblasts are known to differentiate into endothelial cells (endothelial-to-mesenchymal transition).
• The potential for cardiac fibroblasts to adopt an endothelial fate and contribute to neovascularization after cardiac injury remains unexplored.

Purpose of the Study:

• To investigate whether cardiac fibroblasts can transition into endothelial cells after cardiac injury.
• To determine the role of the transcription factor p53 in this process.
• To assess the therapeutic potential of modulating this transition for cardiac repair.

Main Methods:

• Utilized genetic fate mapping techniques in a cardiac injury model.
• Analyzed the phenotypic and functional characteristics of fibroblast-derived endothelial cells.
• Investigated the impact of p53 modulation (loss and stimulation) on cell fate, vascularization, and cardiac function.

Main Results:

• Cardiac fibroblasts were observed to rapidly adopt an endothelial-cell-like phenotype post-ischaemic cardiac injury.
• Fibroblast-derived endothelial cells displayed characteristics of native endothelial cells.
• Loss of p53 in fibroblasts impaired endothelial cell formation, reduced vascular density, and worsened cardiac function.
• p53 pathway stimulation enhanced mesenchymal-to-endothelial transition, improved vascularity, and improved cardiac function.

Conclusions:

• Mesenchymal-to-endothelial transition by cardiac fibroblasts is a significant contributor to neovascularization in the injured heart.
• The transcription factor p53 plays a critical regulatory role in this cellular reprogramming.
• Modulating the p53 pathway presents a promising therapeutic strategy for promoting cardiac repair and enhancing vascularity after myocardial infarction.