|
(426) AGE-RELATED CHANGES IN GENE EXPRESSION IN LEYDIG CELLS OF BROWN NORWAY RATS. Chen, Haolin1, Luo, Lindi1, Kim, Jong-Min1, Zirkin, Barry1, 1 Division of Reproductive Biology, Dept of Biochemistry and Molecular Biology, Baltimore, MD ABSTRACT- In a previous study, we used the Clontech Atlas Rat Stress/Toxicology Array (200 genes) to demonstrate that Leydig cell aging is accompanied by changes in a subset of Leydig cell genes. Herein, we extend this analysis by using an array (Atlas Rat 1.2 Array) that consists of about 1200 rat cDNAs. Leydig cells were isolated from Brown Norway rats of 4 and 22 months of age. To minimize experimental variation, quantitative data for individual genes were normalized against the total levels of all mRNAs on each membrane. A gene was considered to be detectable if its intensity was at least twice the average background of the membrane. A given gene was considered to have changed with aging if consistent results were obtained in at least 4 of 5 replicate experiments, and if differences between young and old levels was at least 1.5-fold. About 25% of the 1200 genes were consistently detectable. Among these, 20 consistently decreased and 21 increased. Prominent among the genes that decreased were those involved in steroid and lipid metabolism pathways (P450scc, 3 KEY WORDS: Leydig Cell, Aging, Brown Norway Rat, Gene Expression by Array Analysis |
-HSD, P450c17, long chain-specific acyl-CoA dehydrogenase, fatty acid-binding protein) and cholesterol import and mobilization (scavenger receptor class B type I, carboxyesterase). Genes of the free radical scavenger family (glutathione transferases, type I SOD) also decreased. Two major gene families that increased with age are DNA binding proteins/transcriptional factors (STAT3, IRF1, Id-3, I-kB
) and immune system proteins (IL-1, IL-6, TNF). Finally, a number of important individual genes decreased with age, including receptors (HGFR, galanin R2, acetylcholine R), translation protein (EIF-2