The effect of dietary fatty acids on cellular calcium handling mechanisms in cardiac muscle [ 2002 - 2004 ]

Research Grant

Researchers: Prof David Saint (Principal investigator)

Brief description A major health problem in the developed countries is cardiovascular disease, which is manifest as high blood pressure, stroke, heart attack and abnormalities of heart rhythm, or cardiac arrhythmias. A western diet, ie. one high in animal fat, or saturated fats, may be to blame. Human epidemiological studies have shown that consumption of a diet high in saturated fats is correlated with a propensity to arrhythmias while a diet high in polyunsaturated fatty acids (PUFAs) can confer protection from coronary heart disease and cardiac arrhythmias. The mechanisms underlying these effects are not fully understood. The contraction of the heart depends on changes in calcium inside the individual muscle cells. Abnormalities of the way calcium is handled in the cells leads to abnormalities of contraction and to a certain types of arrhythmia. Over the last 5 to 10 years, technological developments have enabled us to examine changes in calcium in living heart cells at microscopic level. It is possible to fill individual living cells with a fluorescent dye which changes either the magnitude or the wavelength of its fluorescence according to the ambient calcium concentration. Cells filled with these dyes are examined with a laser scanning confocal microscope, in which a very tightly focussed laser beam excites the dye and the resulting fluorescence is gathered by a computer controlled image analysis system. In this way we can measure the calcium concentration within the cells with a spatial resolution of about 1-1000 of a millimetre, and a time resolution of about 1-100 of a second. Using these techniques, we have found that supplementing the diet of rats with either PUFAs or saturated fats produces a dramatic change in the way that calcium is stored and released in their heart cells. This effect of dietary fats has not been reported before, and it may represent an important clue as to how these substances protect against many cardiac arrhythmias.

Funding Amount $AUD 275,765.70

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant