Age-associated cardiac dysfunction in Drosophila melanogaster

The fruit fly, Drosophila melanogaster; has served as a valuable model/orga nism for the study of aging and was the first organism possessing a circula tory system to have its genome completely sequenced. However, little is kno wn about the function of the heartlike organ of flies during the aging proc ess. We have developed methods for studying cardiac function in vivo in adu lt flies. Using 2 different cardiovascular stress methods (elevated ambient temperature and external electrical pacing), we found that maximal heart r ate is significantly and reproducibly reduced with aging in Drosophila, ana logous to observations in elderly humans. We also describe for the first ti me several other aspects of the cardiac physiology of young adult and aging Drosophila, including an age-associated increase in rhythm disturbances. T hese observations suggest that the study of declining cardiac function in a ging flies may serve as a genetically tractable model for genome-wide mutat ional screening for genes that participate in or protect against cardiac ag ing and disease.