Future

The Heart Can Mend Itself, A New Hope For Cardiac Research

Like brain cells, those of the heart were long thought unable to regenerate. Science is showing this to be false, though applying treatment accordingly is still in its infancy.

Illustration: Nicolas Raymond
Illustration: Nicolas Raymond
Gianna Milano

MILAN — Dr. Giulio Pompilio credits stem cell research for overturning a long-held belief about the heart.

The cardiovascular surgeon, who heads the Vascular Biology and Regenerative Medicine Unit at Milan’s Monzino Cardiology Center, says the heart is equipped with self-regenerating capabilities, a fact that holds great potential for treating cardiac problems.

“We used to think the same thing about the brain, but today we know that’s not true," says Pompilio. “The idea that the cells in our hearts were only able to increase in volume and length, but not reproduce and change, has now been proven wrong.”

The old theory was first thrown into doubt in the 1990s when studies suggested that the heart has intrinsic regenerative capabilities, and there were several isolated observations of cells seen dividing after heart attacks, as well as in pathological conditions.

“The scientific community was so set on the idea that the heart couldn’t repair itself that experimental research used stem cells from other parts of the body, including the spine and musculoskeletal system,” the surgeon explains.

Stem cells are present in almost every organ in our bodies, including the heart, so the main question is this: Why are our hearts unable to cope alone with diseases that weaken it? Why does scar tissue form after a heart attack instead of new healthy cells?

“Today we know that there are progenitor cells in the heart, but we don’t have a clear understanding of the precursory hierarchy of those muscular tissues,” Pompilio says. “By ‘hierarchy’ I mean the ability to specify where these cells come from. The heart, in all conditions, has a "turnover," that is, a mechanism for renewing cells.”

Proof came from a study in 2009, when researchers at the Karolinska Institute in Stockholm showed that cardiac cells did, in fact, renew — albeit slowly. Taking advantage of the knowledge of the levels of radioactivity that were the consequence of nuclear tests begun in the 1950s, the researchers discovered that the disparity of radioactivity observed in the atmosphere and in the heart were due to cardiac cells’ ability to regenerate. It’s a limited change, however, with a 25-year-old estimated to be able to change by 1% annually.

“By the time we’re 70, almost half of the cells in our heart have been replaced by new ones. It’s a slow process but it’s continuous,” Pompilio says.

The discovery inevitably has led to other questions about development during embryonic and fetal stages as well. For example, at what stage exactly does the heart’s development stop?

There are plenty of questions that still need answers in order to lead to possible treatments. “We know that in the early stages of fetal development, as well as post-natal, the capability of regeneration is very high,” says Pompilio. “Within the first few weeks of life, a baby’s heart is much more malleable than an adult’s — there are probably molecular switches that are turned off in the post-natal stage.”

Molecular switches are, therefore, a key element. “Heart failure slightly increases the frequency of the change in an attempt to adapt to the critical situation, but it cannot cope with the problem entirely.” So now, the clinical goal is clear: increase this inadequate response.

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Green

In Argentina, A Visit To World's Highest Solar Energy Park

With loans and solar panels from China, the massive solar park has been opened a year and is already powering the surrounding areas. Now the Chinese supplier is pushing for an expansion.

960,000 solar panels have been installed at the Cauchari park

Silvia Naishtat

CAUCHARI — Driving across the border with Chile into the northwest Argentine department of Susques, you may spot what looks like a black mass in the distance. Arriving at a 4,000-meter altitude in the municipality of Cauchari, what comes into view instead is an assembly of 960,000 solar panels. It is the world's highest photovoltaic (PV) park, which is also the second biggest solar energy facility in Latin America, after Mexico's Aguascalientes plant.

Spread over 800 hectares in an arid landscape, the Cauchari park has been operating for a year, and has so far turned sunshine into 315 megawatts of electricity, enough to power the local provincial capital of Jujuy through the national grid.


It has also generated some $50 million for the province, which Governor Gerardo Morales has allocated to building 239 schools.

Abundant sunshine, low temperatures

The physicist Martín Albornoz says Cauchari, which means "link to the sun," is exposed to the best solar radiation anywhere. The area has 260 days of sunshine, with no smog and relatively low temperatures, which helps keep the panels in optimal conditions.

Its construction began with a loan of more than $331 million from China's Eximbank, which allowed the purchase of panels made in Shanghai. They arrived in Buenos Aires in 2,500 containers and were later trucked a considerable distance to the site in Cauchari . This was a titanic project that required 1,200 builders and 10-ton cranes, but will save some 780,000 tons of CO2 emissions a year.

It is now run by 60 technicians. Its panels, with a 25-year guarantee, follow the sun's path and are cleaned twice a year. The plant is expected to have a service life of 40 years. Its choice of location was based on power lines traced in the 1990s to export power to Chile, now fed by the park.

Chinese engineers working in an office at the Cauchari park

Xinhua/ZUMA

Chinese want to expand

The plant belongs to the public-sector firm Jemse (Jujuy Energía y Minería), created in 2011 by the province's then governor Eduardo Fellner. Jemse's president, Felipe Albornoz, says that once Chinese credits are repaid in 20 years, Cauchari will earn the province $600 million.

The Argentine Energy ministry must now decide on the park's proposed expansion. The Chinese would pay in $200 million, which will help install 400,000 additional panels and generate enough power for the entire province of Jujuy.

The park's CEO, Guillermo Hoerth, observes that state policies are key to turning Jujuy into a green province. "We must change the production model. The world is rapidly cutting fossil fuel emissions. This is a great opportunity," Hoerth says.

The province's energy chief, Mario Pizarro, says in turn that Susques and three other provincial districts are already self-sufficient with clean energy, and three other districts would soon follow.

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