Heart disease is among the leading causes of death for both adults and children. Mammalian hearts have very limited regenerative capacity and heal by scarring and hypertrophy after heart injury, which results in decreased cardiac performance. By contrast, zebrafish have remarkable regenerative capacity. The molecular mechanisms of zebrafish heart regeneration are not understood. The goal of my lab is to define the molecular and cellular mechanisms of heart regeneration in zebrafish with the long-term goal of enhancing regenerative capacity and replacing defective tissues in diseased human hearts.
We use genetic and genomic approaches to dissect the process of zebrafish heart regeneration. Using gene expression profiling, we identified a set of genes that are differentially expressed during heart regeneration. We would like to address the following basic questions: How do these genes contribute to heart regeneration in zebrafish? Does regeneration recapitulate the developmental process? Are stem cells also involved in this regeneration process? The functions of these genes will be characterized in cultured cardiomyocytes in vitro, zebrafish embryos and regenerating hearts in vivo.
Most zebrafish genes are highly conserved with mammalian homologues. However, zebrafish can regenerate heart but mammals can't. We would like to test the two possibilities that contribute to the incapability of regeneration: 1 mammalian hearts fail to express these genes upon injuries at the right time and place; 2. mammalian cardiomyocytes response to stimuli differently from zebrafish cardiomyocytes.
Our work may lead to discovery of important factors/pathways that can contribute to pharmaceutical or cellular therapies for ischemic or congenital heart diseases.