Their findings, presented Nov. 11 at the American Heart Association (AHA) Scientific Sessions conference in New Orleans, suggest that doctors could use hydrogen sulfide to treat humans with heart failure.

Best known for its rotten-egg smell, hydrogen sulfide can pose a deadly threat to miners or sewer workers. However, scientists have recently found that enzymes within the body produce the gas in small, physiological amounts, with multiple beneficial effects such as regulating blood pressure and attenuating inflammation.

David Lefer, PhD, professor of surgery at Emory University School of Medicine, and his team created a model of heart failure in mice by blocking their left coronary arteries either temporarily for an hour or permanently, causing part of their heart muscles to die. Hydrogen sulfide was administered intravenously once a day for a week.

John Calvert, PhD, assistant professor of surgery working with Lefer, presented the findings at the AHA Meeting. "Our results show that hydrogen sulfide can blunt the impact of heart failure on heart function and mortality in a mouse model of heart failure," Calvert says.

Four weeks after artery blockage, mice treated with hydrogen sulfide had an ejection fraction, a measure of heart function, about a third larger than controls (36 compared to 27 percent). He and his colleagues also found similar effects in mice engineered to make more of an enzyme that generates hydrogen sulfide.

Heart failure, a leading cause of hospitalization for the elderly, describes a situation when the heart muscle cannot pump enough blood to meet the body's needs. Previous injury to the heart muscle from a heart attack, obesity, diabetes or high blood pressure are all contributing factors.

In a separate presentation, Calvert (Monday, Nov. 10, 10 a.m. ET) presented experimental data on how hydrogen sulfide works in the heart. The gas appears to stimulate heart muscle cells to produce their own antioxidants and molecules that stave off programmed cell death, a response to the loss of blood flow.

emory

Privatdozent Dr Tobias Pischon, the lead author of the paper from the German Institute of Human Nutrition in Potsdam-Rehbr cke, said: "The most important result of our study is the finding that not just being overweight, but also the distribution of body fat, affects the risk of premature death of each individual. Abdominal fat is not only a mere energy depot, but it also releases messenger substances that can contribute to the development of chronic diseases. This may be the reason for the link."

The new research does not reveal why some people have a larger waist than others but the researchers believe that a sedentary lifestyle, poor diet and genetic predisposition are probably key factors.

Professor Riboli added: "The good news is that you don't need to take an expensive test and wait ages for the result to assess this aspect of your health - it costs virtually nothing to measure your waist and hip size. Doctors and nurses can easily identify people who need to take certain steps to improve their health by routinely monitoring these measurements. If you have a large waist, you probably need to increase the amount of exercise you do every day, avoid excessive alcohol consumption and improve your diet. This could make a huge difference in reducing your risk of an early death."

Professor Riboli leads a new Interventional Public Health Clinical Programme Group at the UK's first Academic Health Science Centre (AHSC). The AHSC is a unique partnership between Imperial College London and Imperial College Healthcare NHS Trust, which aims to ensure that the benefits of research reach patients more quickly than ever before. Professor Riboli's Interventional Public Health group will find new ways of improving people's health in order to prevent them developing conditions such as diabetes and obesity.

For today's prospective EPIC study the researchers looked at 359,387 participants from 9 European countries. The average age of the participants when data were first collected was 51.5 years of age, and 65.4% of the participants were women. During the follow-up period, which averaged 9.7 years, 14,723 of the participants died. Participants with a high BMI, compared with those in the medium range, died more often from cardiovascular diseases or from cancer. Participants with a low BMI tended to die more frequently from respiratory diseases.

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