Damaged heart could be coaxed into mending itself, claim scientists
A broken heart could soon be able to mend itself after scientists discover a way of converting ordinary tissue into beating muscle cells.
In as little as five years, researchers hope to be able to coax the heart into regenerating itself, repairing the damage caused by cardiac arrests and old age.
The revolutionary treatment could be possible after scientists discovered a technique for turning ordinary connective tissue into muscle cells inside the heart.
It works in a similar way to stem cells but instead of the 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.
Around 700,000 people in Britain suffer from heart failure because it has virtually no ability to repair itself after an attack.
The main problem is that 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.
Now Professor Deepak Srivastava at the Gladstone Institute, University of California, and his team have discovered a way of reprogramming fibroblasts into cardiomyocytes.
The system involves slowly administering three substances – using an artificial tube called a stent – into the blood that trigger the conversion.
Professor 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 reprogram the existing fibroblasts in the heart, said Professor Srivastava.
“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.
“It is ambitious, but not unreasonable, to imagine being ready for a clinical trial in the next five years.”
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 per cent eventually made the switch.
“The ability to reprogram fibroblasts into cardiomyocytes has many therapeutic implications,” explained Dr. Srivastava who published his findings in the journal Cell.
“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.”.