A new study helps in explaining how a class of diabetes drugs raises the risk of heart failure. Thiazolidinediones (TZDs) are a group of drugs used for diabetes and have been linked with heart failure, a condition in which the heart cannot pump enough blood through the body. 

In the study, the researchers found that PPAR, a molecule activated by TZDs supports one aspect of heart failure. Initially during the study, the researchers were not thinking on the lines of diabetes drugs. They wanted to find out what happens when a tissue enlarges.

They have thought that when heart enlarges, like it does during heart attack or chronic blood pressure, it exceeds its nutrient and oxygen supply. The increase in size has the heart pumping more blood, but it weakens the organ. Enlarged hearts work more to get oxygen and switch from burning fat to glucose, which provides energy without oxygen but is less efficient.

The cells in the heart weaken and accumulate fat. The researchers have found that PPAR may lead to this downfall. They found that people with heart failure had high levels of PPAR in heart tissue. High levels of PPAR were found in hearts of the mice as well, experimentally manipulated to model the condition. When they extracted PPAR from the heart cells of the mouse, the cells did not accumulate fat and did not die.

The study is published in the June pull-out of Cell Metabolism.