Heart Research in Africa - Responding to our Future Epidemic

Dr Michael Sack

"We've found out that if a heart is exposed to ischaemia only for a short while, so that no cells die, the heart actually becomes more resistant to heart attacks. So now, using genetically manipulated mouse models, we can find out what the molecular mechanism of this resistance is - ultimately designing medication that can have the same effect."

The incidence of cardiovascular disease, especially atherosclerosis (heart attacks and strokes) has begun to rise in the developing regions of Africa. This epidemiological emergence of degenerative western-type cardiovascular disease is not unexpected and parallels the pattern that occurred in e.g. urban India. This transition from the rheumatic and nutritional heart diseases towards atherosclerotic diseases is mainly because of a change in lifestyle. Urbanisation, stress, increased living standards and the 'Western' diet - all contribute to this phenomenon. Hence, in the current climate of the focus of research into the HIV/Aids arena this pending epidemic may be being ignored. 

To counter this, the South African Medical Research Council and the University of Cape Town's Medical School decided to set up a cardiology research institute to help combat these problems. Two and a half years later, the Hatter Institute for Cardiology Research is a vibrant biomedical research laboratory. Professor Michael Sack, who leads the Institute, says their main areas of research are twofold: to investigate how the human heart can be made more resistant to heart attacks; and to understand why and how the heart goes from hypertrophy (enlargement) to failure. 

"If a heart was exposed to myocardial infarction (a heart attack), the heart tissue dies as a result of a lack of oxygen and energy. But we've found out that if a heart is exposed to ischaemia only for a short while, so that no cells die, the heart actually becomes more resistant to heart attacks. So now, using genetically manipulated mouse models, we can find out what the molecular mechanism of this resistance is - ultimately designing medication that can have the same effect," he says.

Hypertension (High Blood Pressure) and diseases such as rheumatic fever cause people to develop thickened hearts - called cardiac hypertrophy. "We investigate, on a molecular level using the mouse models, how and why the heart change from its thickened, adapted state (hypertrophy) to a big, baggy pump that's not working (heart failure). Using the mice you can 'knock out' certain genes or add others to see exactly which proteins are involved in the process," Prof. Sack explains. Understanding this process should also enable us to devise new and novel therapies to combat or delay the development of heart failure  In its brief history, the Hatter Institute has recruited four postdoctoral fellows. Currently, two science students are registered for master's degrees and two more for Ph. D. degrees. Moreover, three clinicians are working in the laboratory and two of them have registered for Ph.D. degrees. "I believe this is of pivotal importance in the maintenance of international standards of academic medicine in South Africa," says Prof. Sack.

The scientific outputs from the laboratory have also given South Africa increased exposure in the international cardiology arena. "Since 1999, numerous scientific papers have been presented at the annual American Heart Association meetings and the Institute has begun to publish extensively in International Biomedical Research Journals.

The Institute is receptive to establish collaborative research initiatives with other Universities in Africa and Prof. Sack believes that the development of critical mass across numerous centres is essential to prevent the isolation and stagnation of this vitally important and relevant research in Africa. 

 

December 2001