Caloric restriction decreases ER stress in liver and adipose tissue in ob/ob mice

► Caloric restriction (CR) reduced the weight of ob/ob mice. ► CR reduced ER stress markers such as phosphorylated PERK and eIF2α in ob/ob mice. ► CR reduced JNK and IRS-1 serine phosphorylation in ob/ob mice. ► CR improved glucose tolerance and hepatic insulin action in ob/ob mice. ► Reduction in ER stress by CR was comparable to that by a chemical chaperone PBA.