Human Embryonic Stem Cell Secretions Minimize Tissue Injury After Heart Attack

Although the vast majority of emails I send to scientists and academics inviting them to sign Declan's petition to the UN on research cloning of embryos and stem cells are still going to spam boxes (or to cyberspace, see blog of 4 September "Obama: Yes to stem cells, funding"), I have compiled the email addresses of medical practitioners from Israel's Hadassah Medical Organization (see blog of 10 September "Human Embryonic Stem Cells Reduce Multiple Sclerosis Symptoms") to send Declan’s email to tomorrow.

On Friday, I emailed 77 scientists and got only two out-of-office autoreplies – we didn't get one single signatory despite that 31 went to the Department of Chemistry at Yale University, from which we have two signatories, one of them a Nobel laureate. Perhaps to say that I will be emailing tomorrow is wishful thinking though since on Thursday I was arrested at 12.30am after I refused to be 'moved on' as result of having nowhere else to sleep (see blog here); and on Friday Declan received an email from the City of London police informing him that the police operation under which I was arrested "is likely to continue for the foreseeable future" (see previous blog).

Scientists of the Institute of Molecular Cell Biology in Singapore

Scientists from the Institute of Medical Biology (IMB) and
Bioprocessing Technology Institute (BTI), under Singapore's Agency for Science, Technology and Research (A*STAR), and the University Medical Center Utrecht in the Netherlands have jointly developed a novel way to improve survival and recovery rate after a heart attack (ScienceDaily, 11/9). This method, the first non-cell based therapeutic application of human embryonic stem cells, entails using secretions from stem cells. Said Dr Lim Sai Kiang, IMB, who leads the group from Singapore: "Using secretion instead of cells allows us to circumvent many highly intractable problems such as tumour formation, immune compatibility, cell viability, delivery, costs and timeliness." Unlike the more common approach of directly administering stem cells for therapy, this new method carries negligible risk of tumour formation or rejection by the body.

The scientists discovered that this approach could minimise heart injury after a heart attack. This is particularly important as the heart has a limited ability to regenerate. The preclinical work was carried out on pigs, the closest animal approximation to the human heart in terms of size, structure and function, and the findings were published in science journal Stem Cell Research. The research findings are especially important as they show that the new method can overcome the unwanted side effects of reperfusion, the best therapeutic option currently available to heart attack patients.

Reperfusion is the restoration of blood flow to the oxygen-deprived heart after a heart attack, ScienceDaily explains. Heart attack or Myocardial Infarction (MI) occurs when blood flow to part of the heart is blocked and the heart muscle is deprived of oxygen. If allowed to persist, prolonged oxygen deprivation causes cell death and irreversible loss of heart function, and inevitably progresses to heart failure and death. To minimise heart muscle damage and preserve the pumping action of the heart after MI occurs, early reperfusion by standard medical treatments such as angioplasty (commonly known as "ballooning") or bypass surgery is carried out in the hospital. Despite this, most MI patients suffer additional irreversible cardiac muscle cell loss, ironically as a result of these treatments a condition known as reperfusion injury.

The researchers found that the administration of secretion from stem cells minimised heart injury by enhancing reperfusion therapy and reducing tissue death by another 60%. Heart function was also markedly improved. By demonstrating the efficacy of this secretion in an experimental pig model, currently the best approximation to a human heart attack patient undergoing reperfusion therapy, the researchers have addressed the longstanding problem of reperfusion injury in the most clinically relevant experimental setting.

Said the advisor to the team of researchers in Singapore, Professor Lee Chuen-Neng, who is the Head of the Department of Cardiac, Thoracic and Vascular Surgery at the National University Hospital, Singapore and Chair of Surgery at the National University Health System, Singapore: "This is a major discovery of clinical significance. There are some problems and issues associated with the use of stem cells to treat heart attacks and blocked arteries in the heart, and with this new method, many of these issues are removed. Potentially, we may have an important way to treat heart attacks. More tests will need to be done and human trials planned." This discovery is all the more significant because the therapy for reperfusion injury remains an unmet need despite three decades of huge resource investment, thousands of research papers and hundreds of experimental protocols, ScienceDaily adds. This preclinical study had come amidst an international call to improve the translation of preclinical experimental therapies for reperfusion injury to clinical applications.

In a recent article titled “America misses yet another boat”, the American Chronicle points out that America is falling behind in the global race for new patents and pharmaceuticals based on stem cell research. “While the debate centers on whether or not, as held by the fundamentalists, these fertilized embryos are ‘unique human lives with inherent dignity and matchless value’, the rest of the world quite wittingly is taking advantage of the sleeping giant America, reveling in the Bush vetoes and lack of funding,” says the American Chronicle. Countries that have allowed embryonic stem cell research are Australia, Brazil, Spain, Canada, Sweden, Belgium and the United Kingdom. Three other countries worthy of note are Switzerland, South Korea and Singapore. Switzerland solved the political problem by putting the matter before voters in the form of a national referendum. South Korea has made strong advancements in stem cell research, due to very flexible policies regarding research. “Neck-in-neck in the global race for stem cell research, in fact ahead in many scientists´ eyes, is small, rich and enlightened Singapore,” says the American Chronicle. “The list of leading scientists who are happy to work in this thriving environment goes on and on, many from Europe and Japan as well.”