Calorie restriction (CR) leads to a remarkable decrease in adipose tissue mass and increases longevity in many taxa. Since the discovery of leptin, the secretory abilities of adipose tissue have gained prominence in the responses to CR. We quantified transcripts of epididymal white adipose tissue of male C57BL/6 mice exposed to graded levels of CR (0% to 40% CR) for three months. The numbers of differentially expressed genes (DEGs) involved in NF-κB, HIF1-α and p53 signalling increased with increasing levels of CR. These pathways were all significantly downregulated at 40% CR relative to 12h ad libitum feeding. In addition, graded CR had a substantial impact on DEGs associated with pathways involved in angiogenesis. Of the 497 genes differentially expressed with graded CR, 155 of these genes included a signal peptide motif. These putative signalling proteins were involved in the response to ketones, TGF-β signalling, negative regulation of insulin secretion and inflammation. This accords with the previously established effects of graded CR on glucose homeostasis in the same mice. Overall these data suggest reduced levels of adipose tissue under CR may contribute to the protective impact of CR in multiple ways linked to changes in a large population of secreted proteins.
|Number of pages||10|
|Journal||The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences|
|Early online date||27 May 2017|
|Publication status||Published - 2 Mar 2018|
- biology of ageing