Research Highlights

Blocking protein Meis1 may regenerate heart tissue

Published online 17 April 2013

Hazem Zohny

Generating new heart muscle cells (cardiomyocytes) in mice can be achieved by blocking the action of a protein called Meis1, according to a new study published in Nature.

Adult hearts in mammals cannot regenerate tissue to recover from injury, but the hearts of mammals in the first week after birth are able to do so by multiplying existing cardiomyocytes.

The team, including Egyptian researchers Ahmed Mahmoud and Hesham Sadek from The University of Texas Southwestern Medical Center, as well as Ahmed Koura from Ain Sham University, Cairo, found that Meis1 regulates the cardiomyocyte cell cycle. If Meis1 is deleted in adult mouse hearts, the proliferation of cardiomyocytes can be reactivated without damaging heart function.

To determine whether the omission of Meis1 increases the total population of cardiomyocytes, the team isolated adult mice cardiomyocytes from wild-type and knockout mice and found a significant increase in the total number of cells in the hearts of knockout mice.

The researchers examined the effect of Meis1 deletion at the postnatal stages of 28 days and 7 months and found that cardiac function and heart size were normal in these mice. In addition, the authors found that increased expression of Meis1 in newborn mice blocked the heart's ability to regenerate.

These findings suggest that Meis1 could be a potential therapeutic target in cases of damage to heart tissue.


  1. Mahmoud, A. et al. Meis1 regulates postnatal cardiomyocyte cell cycle arrest. Nature (2013) doi:10.1038/nature12054