||Overexpression of the adiponectin gene mimics the metabolic and stress resistance effects of calorie restriction, but not the anti-tumor effect
54 , 2015-08-05 , Elsevier Inc.
Adiponectin (Adipoq), a peptide hormone secreted from the white adipose tissue, may play a role in the antiaging and/or anti-tumor effects of calorie restriction (CR). We analyzed metabolic traits in Adipoq geneoverexpressing mice fed ad libitumwith a regular diet (RD) or a high-fat diet (HFD), or fed 30% CR of RD initiated at 12weeks of age. Adipoq-RD and -HFD mice at 6 months of age showed reduced blood glucose and insulin concentrations, and thus increased insulin sensitivity, compared withWTmice fed a RD or a HFD. In the epididymal white adipose tissue in Adipoq mice, senescence-like changes such as upregulation of p53 protein and of biomarkers of inflammation, Cd68 and Ccl2 mRNA, were ameliorated compared withWT-RD and WT-HFD mouse tissues. Resistance to stress induced by lipopolysaccharide was also strengthened in Adipoq mice compared with WT mice. These metabolic changes and stress resistance were also noted in the WT-CR mice, suggesting
that Adipoq plays a part in the effect of CR. In contrast, in an allograft tumor growth model, tumor growth was not inhibited in Adipoq mice. The present findings suggest that Adipoq plays a part in the anti-aging, but not in the anti-tumor, effects of CR.