Alert to science journalists looking for active debate: Emory cardiology researchers Nawazish Naqvi and Ahsan Husain are not afraid of controversy in their field.
In a 2014 Cell paper, they challenged the long-held assumption that after birth, cardiac muscle cells do not divide, showing a dramatic burst of thyroid hormone-driven cell division in the hearts of preadolescent mice. This finding has implications for regenerative medicine if it can be harnessed, but also stimulated a cluster of papers aiming to refute their findings in Cell the following year (and more are coming).
A second assumption that they’ve challenged more recently is that hours after a heart attack, endangered cardiac muscle cells can’t be rescued. Husain and Naqvi’s paper, published this week in PNAS, shows that the enzyme chymase — produced by a type of immune cell called mast cells — limits the heart’s ability to heal itself. Critically, differences in the extent of damage seen in mice lacking chymase and controls show up days after an artificial heart attack. More here.