Damaged heart could soon be able to mend itself

A file photo of awarness walk on World Heart Day in Chennai. Researchers led by an Indian-origin scientist at the Gladstone Institute, University of California, have found a novel way to coax a damaged heart to mend itself. Photo: R. Ragu

Researchers led by an Indian-origin scientist at the Gladstone Institute, University of California, have found a novel way to coax a damaged heart to mend itself.

The revolutionary treatment could be possible after the scientists discovered a technique for turning ordinary connective tissue into muscle cells inside the heart.

It works in a similar way like stem cells, but instead of new cells being grown outside the body and then injected back in, the technique simply makes the cells switch at the point where they are needed.

When beating muscles cells - known as cardiomyocytes - die during an attack, there is no way to reactivate them and the surrounding connective tissue - known as fibroblasts - cannot take over their role.

Indian-origin scientist Deepak Srivastava and his team have discovered how to reprogramme fibroblasts into cardiomyocytes.

The system involves slowly administering three substances - using an artificial tube called a stent - into the blood that trigger the conversion.

Srivastava believes this could be achieved over just two weeks.

“We first have to test if the same factors can convert human fibroblasts to beating heart muscle and then find ways to safely introduce these factors, or small molecules that mimic these factors, into the coronary circulation so they can reprogramme the existing fibroblasts in the heart,” telegraph.co.uk quoted Srivastava as saying.

“I envision such factors being loaded into a stent that is placed in the coronary artery and can elute (allow to emerge) the reprogramming factors over 1-2 weeks.” Srivastava said

“It is ambitious, but not unreasonable, to imagine being ready for a clinical trial in the next five years.” Srivastava added.

The team found that they needed a combination of just three substance - Gata4, Mef2c, and Tbx5 - to efficiently convert fibroblasts into cells that could beat like cardiomyocytes.

One day after the three factors were introduced into mouse hearts, fibroblasts turned into cardiomyocyte-like cells within the beating heart. Up to 20 percent eventually made the switch.

“The ability to reprogramme fibroblasts into cardiomyocytes has many therapeutic implications,” said Srivastava.

“Half of the cells in the heart are fibroblasts, so the ability to call upon this reservoir of cells already in the organ to become beating heart cells has tremendous promise for cardiac regeneration.” Srivastava added.