BY DANA DiFILIPPO
The Cincinnati Enquirer
A Children's Hospital Medical Center researcher says he has discovered the gene that triggers heart enlargement.
The gene, calcineurin, senses hypertension, the onset of heart attacks and other cardiac problems and causes the heart to expand in an attempt to relieve them, Dr. Jeffery Molkentin said.
That enlargement, known as cardiac hypertrophy, can eventually lead to heart failure and death. One in 500 people develop some form of cardiac hypertrophy.
Given to transplant patients
Cyclosporin A -- a drug commonly used to control rejection in transplanted organs -- inhibits calcineurin, according to the findings, which will appear today in the science journal Cell.
The drug isn't a sure cure for cardiac hypertrophy, because the anti-rejection drug can cause kidney problems and weaken the immune system. But it may be beneficial in severe cases or used in combination with other inhibiting drugs.
And the discovery lays a foundation for further studies.
"No one has been able to show the mechanism that causes cardiac hypertrophy in a living organism," Dr. Molkentin said. "This sets the stage for future studies into other ways to inhibit calcineurin."
Dr. Molkentin and collaborator Dr. Eric Olson started their studies a year ago at the University of Texas-Southwestern Medical Center in Dallas, where Dr. Olson works and Dr. Molkentin was a fellow. Dr. Molkentin, a cardiac biology researcher and assistant professor of pediatrics at Children's, moved to Cincinnati nine months ago. The pair continued their collaboration in Cincinnati; Dr. Molkentin is the study's lead author.
The two researchers genetically engineered mice to carry the calcineurin gene, then treated them with various drugs, including Cyclosporin A.
Dr. Molkentin plans to continue studying the role calcineurin plays in other forms of heart disease.
