Alison Hoang Rose Hills
Cardiac regenerative potential across mammalian phylogeny
The heart, especially in adult mammals, is one of the least regenerative organs as evident in the ongoing battle against cardiovascular diseases. While higher mammals lack the ability to proficiently regenerate myocardial tissue, lower vertebrates, such as zebrafish and newts, experience a robust regenerative response even after major injury. Phylogeny then implies that higher mammals must have lost their cardiac regenerative potential sometime during their evolutionary history. The phylogenic distribution of cardiac regeneration in mammals is not well understood but could serve as an important platform to identify evolutionary pressures and factors controlling regenerative capacity. We hypothesize that orders that have diverged earliest from the higher mammal lineage monotremes, marsupials, and xenarthrans – may have intermediate potential for myocardial regeneration, more representative of that of lower vertebrates. I will be analyzing nuclear content and percent mononucelation of lower mammal cardiomyocytes, proxies for regenerative potential. Secondly, I will be looking at the cardiomyocyte proliferation rate and gene expression of naked mole-rats, a rodent that we hypothesize to have an unusually high regenerative potential.