New Discovery: Reversing Tissue Damage Caused by Heart Attacks

Scientists at the University of Bristol have made a discovery that will help explain the manner in which pericytes, the cells that surround blood vessels, catalyze the growth of new blood vessels. The hormone known as leptin, which is generated by fat cells and regulates the body's energy balance by suppressing the appetite, plays an important role in this process. 

The School of Clinical Sciences' Paolo Madeddu led the study. Madeddu is a professor of Experimental Cardiovascular Medicine. Madeddu's research team received funding from Heart Research UK. The study's details were recently published in Scientific Reports. 

Heart Attack Treatment

Coronary artery bypass surgery is one of the more popular treatments for heart attacks. It makes use of blood vessels within the leg or other body sites to bypass the artery that is blocked. The result is improved blood flow to the heart. However, this is a major and invasive surgery that requires a lengthy recovery time.

Findings

The research team found pericytes generated 40 times more leptin when they were subjected to low oxygen levels. This trend continued until oxygen levels returned to their normal state. It is possible this will help tissues build additional blood vessels that boost blood flow and the supply of oxygen. The research shows the many important actions of leptin that result in additional blood vessel growth in sections of the body where tissues are lacking in oxygen. The emergence of new blood vessels, referred to as “angiogenesis” is a key process that occurs in disease as well as a healthy state of existence. Angiogenesis is critically important to the repair of tissues after injury. It also plays an important role in the growth and subsequent spread of cancer.

In most instances, heart attacks occur when the coronary artery is blocked. The subsequent lack of blood sent to the heart causes significant damage. The research team showed that by stimulating the growth of new blood vessels, pericytes might be able to restore the blood supply to the compromised heart muscle following a heart attack. These findings may also affect cancer treatments as well.

The Study's Importance

The research team identified this new signaling mechanism that could have a major impact on cardiovascular regenerative medicine for years to come. Boosting leptin within pericytes in a compromised heart could help it heal much more quickly. Blocking the generation of leptin within cancerous pericytes could deprive the tumor of key nutrients and subsequently cause it to shrink.