Transcriptional profiling reveals progeroid Ercc1(-/Δ) mice as a model system for glomerular aging.

BACKGROUND: Aging-related kidney diseases are a major health concern. Currently, models to study renal aging are lacking. Due to a reduced life-span progeroid models hold the promise to facilitate aging studies and allow examination of tissue-specific changes. Defects in genome maintenance in the Ercc1(-/Δ) progeroid mouse model result in premature aging and typical age-related pathologies. Here, we compared the glomerular transcriptome of young and aged Ercc1-deficient mice to young and aged WT mice in order to establish a novel model for research of aging-related kidney disease. RESULTS: In a principal component analysis, age and genotype emerged as first and second principal components. Hierarchical clustering of all 521 genes differentially regulated between young and old WT and young and old Ercc1(-/Δ) mice showed cluster formation between young WT and Ercc1(-/Δ) as well as old WT and Ercc1(-/Δ) samples. An unexpectedly high number of 77 genes were differentially regulated in both WT and Ercc1(-/Δ) mice (p < 0.0001). GO term enrichment analysis revealed these genes to be involved in immune and inflammatory response, cell death, and chemotaxis. In a network analysis, these genes were part of insulin signaling, chemokine and cytokine signaling and extracellular matrix pathways. CONCLUSION: Beyond insulin signaling, we find chemokine and cytokine signaling as well as modifiers of extracellular matrix composition to be subject to major changes in the aging glomerulus. At the level of the transcriptome, the pattern of gene activities is similar in the progeroid Ercc1(-/Δ) mouse model constituting a valuable tool for future studies of aging-associated glomerular pathologies.

Life spanning murine gene expression profiles in relation to chronological and pathological aging in multiple organs.

Aging and age-related pathology is a result of a still incompletely understood intricate web of molecular and cellular processes. We present a C57BL/6J female mice in vivo aging study of five organs (liver, kidney, spleen, lung, and brain), in which we compare genome-wide gene expression profiles during chronological aging with pathological changes throughout the entire murine life span (13, 26, 52, 78, 104, and 130 weeks). Relating gene expression changes to chronological aging revealed many differentially expressed genes (DEGs), and altered gene sets (AGSs) were found in most organs, indicative of intraorgan generic aging processes. However, only ≤ 1% of these DEGs are found in all organs. For each organ, at least one of 18 tested pathological parameters showed a good age-predictive value, albeit with much inter- and intraindividual (organ) variation. Relating gene expression changes to pathology-related aging revealed correlated genes and gene sets, which made it possible to characterize the difference between biological and chronological aging. In liver, kidney, and brain, a limited number of overlapping pathology-related AGSs were found. Immune responses appeared to be common, yet the changes were specific in most organs. Furthermore, changes were observed in energy homeostasis, reactive oxygen species, cell cycle, cell motility, and DNA damage. Comparison of chronological and pathology-related AGSs revealed substantial overlap and interesting differences. For example, the presence of immune processes in liver pathology-related AGSs that were not detected in chronological aging. The many cellular processes that are only found employing aging-related pathology could provide important new insights into the progress of aging.

Dietary n-3 and n-6 polyunsaturated fatty acid intake interacts with FADS1 genetic variation to affect total and HDL-cholesterol concentrations in the Doetinchem Cohort Study.

BACKGROUND: The delta-5 and delta-6 desaturases, encoded by the FADS1 and FADS2 genes, are rate-limiting enzymes in polyunsaturated fatty acid (PUFA) biosynthesis. Single nucleotide polymorphisms in the FADS gene cluster region have been associated with both PUFA concentrations in plasma or erythrocyte membrane phospholipids and cholesterol concentrations in recent genome-wide association studies. OBJECTIVE: We examined whether genetic variations in the FADS gene cluster region interact with dietary intakes of n-3 (omega-3) and n-6 (omega-6) PUFAs to affect plasma total, HDL-, and non-HDL-cholesterol concentrations. DESIGN: Dietary intakes of n-3 and n-6 PUFAs, plasma concentrations of total and HDL cholesterol, and rs174546, rs482548, and rs174570 in the FADS gene cluster region were measured in 3575 subjects in the second survey of the Doetinchem Cohort Study. RESULTS: Significant associations between rs174546 genotypes and total and non-HDL-cholesterol concentrations were observed in the group with a high intake of n-3 PUFAs (> or =0.51% of total energy; P = 0.006 and 0.047, respectively) but not in the low-intake group (P for interaction = 0.32 and 0.51, respectively). The C allele was associated with high total and non-HDL-cholesterol concentrations. Furthermore, the C allele was significantly associated with high HDL-cholesterol concentrations in the group with a high intake of n-6 PUFAs (> or =5.26% of total energy, P = 0.004) but not in the group with a low intake (P for interaction = 0.02). CONCLUSION: Genetic variation in the FADS1 gene potentially interacts with dietary PUFA intakes to affect plasma cholesterol concentrations, which should be investigated further in other studies.