Islamabad - The risk of death from heart attack could rise by more than 50 per cent for people with diabetes, finds a new study by researchers from the University of Leeds in the United Kingdom.

It is well established that people with diabetes are at much greater risk for numerous other health problems, including high blood pressure, heart attack, stroke, and heart disease. For the new study, lead researcher Dr Chris Gale of the School of Medicine at the University of Leeds, and colleagues set out to investigate the long-term risk of death from heart attack, or myocardial infarction, among people with diabetes - a risk that has previously been unclear.

The team analyzed the data of 703,920 individuals and described that described as a “classic” heart attack, where an electrocardiogram (ECG) shows a complete blockage of the coronary artery, causing damage to a large area of the heart.

These results remained after accounting for a number of potentially confounding factors, such as patients’ age, sex, other illnesses, and differences in emergency medical treatment.

Dr Gale says the study provides “robust evidence that diabetes is a significant long-term population burden among patients who have had a heart attack.”

“Although these days people are more likely than ever to survive a heart attack, we need to place greater focus on the long-term effects of diabetes in heart attack survivors.

Dr Chris Gale said that the partnership between cardiologists, GPs and diabetologists needs to be strengthened and we need to make sure we are using established medications as effectively as possible among high-risk individuals.”

Dr Mike Knapton, associate medical director at the British Heart Foundation - which funded the study - says that although it was known that people with diabetes were at greater risk of death from heart attack, these findings show this increased risk is due to diabetes itself, rather than other co-existing conditions.

“This research highlights the need to find new ways to prevent coronary heart disease in people with diabetes and develop new treatments to improve survival after a heart attack,” he adds.

In future studies, the researchers plan to investigate the underlying mechanisms that might explain why diabetes raises the risk of death from heart attack.

Memory improved by protein released in response to running

A number of studies have suggested exercise can boost cognitive function, but the underlying mechanisms of this association have been unclear. Now, new research sheds light on how running can improve learning and memory.

Senior author of this latest research, Henriette van Praag, a neuroscientist at the National Institute on Aging (NIA) - part of the National Institutes of Health (NIH) - and colleagues say their study is the first to link cathepsin B with spatial learning.

The researchers decided to focus on the role of cathepsin B in response to exercise after screening a number of proteins likely to be secreted by muscle tissue and transported to the brain.

In a lab dish, the team exposed muscle cells to various exercise-mimicking compounds and found that cathepsin B was the most secreted protein.

The researchers also identified high levels of cathepsin B in the blood and muscle cells of mice that had been running on an exercise wheel every day for several weeks.

What is more, on applying the protein to brain cells, the team found that it triggered the production of molecules that play a role in brain cell development and growth - a process known as neurogenesis.

With these findings in mind, van Praag and colleagues set out to investigate how cathepsin B might impact memory recall in response to physical activity.

The researchers explain that normal mice usually learn the location of a platform after a few days of learning the circuit. However, when both groups of mice ran before the water maze test, the researchers found that the mice lacking the ability to produce cathepsin B could not recall the location of the platform, but the normal mice could.

The team believes these findings indicate that cathepsin B may play an important role in memory in response to exercise.

Henriette van Praag said that “Nobody has shown before cathepsin B’s effect on spatial learning. We also have converging evidence from our study that cathepsin B is upregulated in blood by exercise for three species - mice, Rhesus monkeys, and humans.

Moreover, in humans who exercise consistently for 4 months, better performance on complex recall tasks, such as drawing from memory, is correlated with increased cathepsin B levels.”