Tissue specific and non-specific changes in gene expression by aging and by early stage CR
Chunxiao Fu1, Morgen Hickey, Melissa Morrison
1Department of Biological Science, The University of Tulsa, 600 S. College Ave., Tulsa, OK 74104, USA.
Mechanisms of Ageing and Development
|November 10, 2006
Summary
Aging impacts gene expression across heart, liver, and hypothalamus tissues. Early calorie restriction (CR) in mice also modifies gene expression, with some overlap in affected genes and biological processes between aging and CR.
Area of Science:
- Genomics
- Aging Research
- Molecular Biology
Background:
- Aging is associated with significant alterations in gene expression patterns.
- Calorie restriction (CR) is known to extend lifespan in rodents and also influences gene expression.
Purpose of the Study:
- To investigate how aging and early-stage calorie restriction (CR) affect gene expression across multiple tissues (heart, liver, hypothalamus) in mice.
- To identify common and distinct gene expression changes induced by aging and CR.
Main Methods:
- Gene expression profiling was performed on heart, liver, and hypothalamus tissues from young ad libitum-fed (AL), young CR, and old AL male C57BL/6 mice.
- Analysis included identifying differentially expressed genes and performing Gene Ontology (GO) enrichment analysis for biological processes and molecular functions.
Main Results:
- Aging significantly altered gene expression in all three tissues, with thousands of genes affected in liver and hypothalamus.
- Early-stage CR also induced significant changes in gene expression across the three tissues.
- Aging upregulated antigen processing/presentation genes, while CR downregulated stress response genes in all tissues studied.
- A notable overlap was observed between aging and CR effects, with 389 common genes, 18 common GO biological processes, and 20 common GO molecular functions identified.
Conclusions:
- Both aging and early-stage calorie restriction induce widespread changes in gene expression across different tissues.
- There is a significant overlap in the molecular pathways affected by aging and CR, suggesting potential shared mechanisms.
- Understanding these tissue-specific and overlapping gene expression changes can provide insights into the aging process and the effects of CR.
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