Senescence-related changes in gene expression in muscle: similarities and differences between mice and men

A microarray study of the effect of senescence in mice on gene expression i n muscle has been published recently. The present analysis was done to eval uate the extent to which the age-related differences in gene expression in murine muscle are also evident in human muscle. RNA extracted from muscle o f young (21-24 yr) and old men (66-77 yr) was studied both by serial analys is of gene expression (SAGE) and by oligonucleotide microarrays. SAGE tags were detected for 61 genes homologous to genes reported to be differentiall y expressed in young and old murine muscle. The microarray had probe sets f or 70 homologous genes. For 17 genes, there was evidence for a similar age- related change in expression in muscles of mice and men. For 32 other genes , there was evidence that the effect of age on the level of expression is n ot the same in mice and men. There was no evidence that older human muscle has increased expression of the stress response genes that are increased in old murine muscle.