Researchers in the US have discovered a new group of stem cells that can give rise to heart muscle cells, known as cardiomyocytes, a study published yesterday said.
The stem cells are located in the outermost layer of the heart and could one day play a critical role in regenerating injured heart tissue, the researchers said.
“In heart failure, you lose cardiomyocytes, so the only way to reverse heart failure is to make more of these cells,” said William Pu, the study’s lead researcher and a pediatric cardiologist at Children’s Hospital in Boston, Massachusetts.
The new findings come on the heels of two earlier breakthroughs.
In 2006 scientists identified another cardiac stem cell — marked by the expression of a gene called Nkx2-5 — with the potential to become either heart muscle or cells lining blood vessels in the organ’s left-sided chambers.
Gene expression is the process by which information encoded in the DNA of a particular gene is transformed into a protein or RNA, which plays a key role in protein synthesis.
Other US researchers discovered a related progenitor heart cell — so-called because of its capacity to generate different types of tissue — that produces the same cell types in the right-sided heart chambers.
Pu’s study, published online in the journal Nature, shows for the first time that new heart stem cells can also be derived from a third type of cardiac stem cell, located within the surface of the organ and identifiable through its expression of a gene called Wt1.
The results were independently verified by another team of scientists at the University of California in San Diego, whose research was published in the same issue of Nature.
Pu and colleagues showed that the cells from the heart’s outer lining, called the epicardium, can not only metamorphose into cardiomyocytes but also into smooth muscle cells, endothelial cells, which line the interior of blood vessels and fibroblasts, found in connective tissue.
“If you are going to regenerate tissue, you need to regenerate the whole tissue, not just the cardiomyocytes,” Pu said in a statement.
The discovery of the new stem cells was an accident. In order to study the role a different gene in the epicardium, the researchers labeled cells in live mouse embryos with red fluorescent protein.
“Unexpectedly, we saw that these epicardial cells were becoming cardiomycytes — it was a lucky observation,” Pu said.
The next challenge, he said, is trying to figure out how a progenitor stem cell decides to become a certain type of functioning cell within the heart, and then how to develop methods to trick the stem cells into transforming into the desired tissue.
Archeologists in Peru on Thursday said they found the 5,000-year-old remains of a noblewoman at the sacred city of Caral, revealing the important role played by women in the oldest center of civilization in the Americas. “What has been discovered corresponds to a woman who apparently had elevated status, an elite woman,” archeologist David Palomino said. The mummy was found in Aspero, a sacred site within the city of Caral that was a garbage dump for more than 30 years until becoming an archeological site in the 1990s. Palomino said the carefully preserved remains, dating to 3,000BC, contained skin, part of the
‘WATER WARFARE’: A Pakistani official called India’s suspension of a 65-year-old treaty on the sharing of waters from the Indus River ‘a cowardly, illegal move’ Pakistan yesterday canceled visas for Indian nationals, closed its airspace for all Indian-owned or operated airlines, and suspended all trade with India, including to and from any third country. The retaliatory measures follow India’s decision to suspend visas for Pakistani nationals in the aftermath of a deadly attack by shooters in Kashmir that killed 26 people, mostly tourists. The rare attack on civilians shocked and outraged India and prompted calls for action against their country’s archenemy, Pakistan. New Delhi did not publicly produce evidence connecting the attack to its neighbor, but said it had “cross-border” links to Pakistan. Pakistan denied any connection to
TRUMP EFFECT: The win capped one of the most dramatic turnarounds in Canadian political history after the Conservatives had led the Liberals by more than 20 points Canadian Prime Minister Mark Carney yesterday pledged to win US President Donald Trump’s trade war after winning Canada’s election and leading his Liberal Party to another term in power. Following a campaign dominated by Trump’s tariffs and annexation threats, Carney promised to chart “a new path forward” in a world “fundamentally changed” by a US that is newly hostile to free trade. “We are over the shock of the American betrayal, but we should never forget the lessons,” said Carney, who led the central banks of Canada and the UK before entering politics earlier this year. “We will win this trade war and
Armed with 4,000 eggs and a truckload of sugar and cream, French pastry chefs on Wednesday completed a 121.8m-long strawberry cake that they have claimed is the world’s longest ever made. Youssef El Gatou brought together 20 chefs to make the 1.2 tonne masterpiece that took a week to complete and was set out on tables in an ice rink in the Paris suburb town of Argenteuil for residents to inspect. The effort overtook a 100.48m-long strawberry cake made in the Italian town of San Mauro Torinese in 2019. El Gatou’s cake also used 350kg of strawberries, 150kg of sugar and 415kg of