*Purpose: Old livers are more damaged by hepatic ischemia and reperfusion (IR) injury than young livers. The aim of this study was to investigate the effects of ischemic and rapamycin preconditioning on IR injury in old livers.

*Methods: Young (8-week-old) and old (60-week-old) mice were subjected to IR or a sham control procedure. The old mice were randomly divided into six groups: IR (CON), IR with ischemic preconditioning (IPC), IR with rapamycin preconditioning (RAPA), IR with combined ischemic and rapamycin preconditioning (IPC+RAPA), IR with 3-methyladenine (CON+3-MA), IR with combined ischemic and rapamycin preconditioning with 3-MA pretreatment (IPC+RAPA+3-MA). Liver injury was evaluated 6 hours after reperfusion. Hepatocellular autophagy induction was also analyzed by western blotting.

*Results: Compared to young mice, old mice showed aggravated liver IR injury. In old mice following IR, IPC+RAPA but not IPC or RAPA alleviated liver injury, as evidenced by lower levels of serum ALT, improved preservation of liver architecture with lower Suzuki scores, and decreased caspase-3 activity compared with CON. In addition, western blot analysis revealed increased LC3B II but decreased p62 protein expression levels in the IPC+RAPA group, indicating that autophagic flux was restored by combined ischemic and rapamycin preconditioning. Furthermore, autophagy inhibition by the inhibitor 3-MA abrogated the protective role in the IPC+RAPA group, while no significant effects were observed in the CON group.

*Conclusions: Our results demonstrated that combined ischemic and rapamycin preconditioning protected old livers against IR injury, which was likely attributed to restored autophagy activation.

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