Gene expression profiling studies of aging in cardiac and skeletal muscles.

To examine transcriptional alterations associated with aging in skeletal muscle and the heart, we and others have used DNA microarrays to compare the gene expression profile of young and old animals. Aging results in a differential gene expression pattern specific to each tissue, and most alterations can be completely or partially prevented by caloric restriction (CR) in both heart and skeletal muscle. Transcriptional patterns of tissues from calorie-restricted animals suggests that CR retards the aging process by reducing endogenous damage and by inducing metabolic shifts associated with specific transcriptional profiles. These studies demonstrate that DNA microarrays can be used in cardiovascular aging research to generate panels of hundreds of transcriptional biomarkers, providing a new tool to measure biological age of cardiac and skeletal muscles and to test interventions designed to retard aging in these tissues.