Pioneering 'Holy Grail' therapy could repair deadly heart attack damage
Pioneering
'Holy Grail' therapy could repair deadly heart attack damage by injecting a
gene to restart growth which stops when we're babies
·
Scientists
at King's College London said their research is 'exciting' progress
·
Millions of
people worldwide have heart failure caused by damaged tissue
·
Experts were
able to restore pigs' hearts to work properly again within weeks
·
A
'Holy Grail' heart failure cure could be on the horizon after scientists worked
out how to regenerate specialised cells in the muscle.
Injecting the gene which drives cell growth in people's
infancy could restore tissue which is damaged during a heart attack, a study on
pigs has found.
Currently, people who have heart attacks are left with
patches of scarring which last forever and can lead to heart failure and
ultimately death.
Scientists have failed to find a way to restore or remove
this dead tissue and get the organ working normally again – but this discovery
may change that.
By restarting a growth process which ends when people are
babies, experts may be able to force the heart to rebuild itself and become
healthy again within weeks.
Researchers from King's College London injected the gene
into the hearts of pigs and found their heart function went back to normal
within a month of a heart attack.
And, because of the similarities between pig and human
hearts, scientists hope the same treatment could be given to people within a
decade.
'It is a very exciting moment for the field,' said
Professor Mauro Giacca, a lead researcher on the study.
'After so many unsuccessful attempts at regenerating the
heart using stem cells, which all have failed so far, for the first time we see
real cardiac repair in a large animal.'
The pioneering treatment could one day offer hope for
people suffering from heart failure, a deadly condition which affects more than
23million people worldwide.
More than 900,000 people in the UK have the condition,
which often follows a heart attack and happens when the organ is too damaged to
pump blood properly.
In their study, researchers managed to inject a gene
called human microRNA-199a (AAV6-miR-199a) into the hearts of pigs after a
heart attack.
HOW DOES THIS TREATMENT WORK?
After heart attacks, which happen around 100,000 times a
year in the UK and 790,000 in the US, people may be left with patches of dead,
scarred heart tissue.
These can lead to heart failure, a lifelong condition in
which damage to the heart stops it from pumping blood properly.
This cannot be cured because the heart cells do not
regenerate themselves, so the ones we develop as babies have to last our whole
lives.
However, scientists found injecting a particular gene,
known as miR-199a, into pigs triggered these specialist cells to start
reproducing again like they did in the womb.
This meant the heart was able to regenerate its damaged
muscle, reduce the scar tissue and function as normal – within a number of
weeks of a heart attack.
Unfortunately the regrowth couldn't be stopped so the
pigs' hearts overdeveloped and most of the animals died, but the researchers
now hope to test a version of the gene which switches off after two weeks when
its job is done.
hey
found this gene stimulated the heart to repair itself by restarting the
reproduction of specialised heart cells called cardiomyocytes.
Cardiomyocytes are almost all developed while a person is
still a foetus – with some further growth after birth – and have to last for
the rest of their lives.
Scientists have until now failed to find a way to make
mature versions of the cells successfully reproduce in a way that regenerates
the heart.
But within weeks of the miR-199a gene being injected into
pigs, their heart function had returned to normal.
However, there was a fatal hiccup – scientists couldn't
stop the redevelopment and the pigs' hearts created so many new cells most of
the animals died.
The team now
hope to trial a new version of the gene which switches off after two weeks, the i newspaper reported.
'A treatment that helps the heart repair itself after a
heart attack is the holy grail for cardiologists,' said the chair of the
British Heart Foundation, Ajay Shah.
'This study convincingly demonstrates for the first time
that this might actually be feasible and not just a pipe dream.'
Professor Giacca said more tests and development are
needed but he is confident the treatment could be available to people within 10
years.
He added: 'It will take some time before we can proceed
to clinical trials.
'We still need to learn how to administer the RNA as a
synthetic molecule in large animals and then in patients, but we already know
this works well in mice.'
Comments
Post a Comment