Atherosclerosis Deteriorates Liver Ischemia/Reperfusion Injury Via Interferon Regulatory Factor-1 Overexpression in a Murine Model

Abstract

Background: Abdominal aortic calcification (AAC) is associated with cardiovascular-related mortality, along with an elevated risk of coronary, cerebrovascular, and cardiovascular events. Notably, AAC is strongly associated with poor overall and recurrence free survival posthepatectomy for hepatocellular carcinoma. Despite the acknowledged significance of atherosclerosis in systemic inflammation, its response to ischemia/reperfusion injury (IRI) remains poorly elucidated. In this study, we aimed to clarify the impact of atherosclerosis on the liver immune system using a warm IRI mouse model.

Methods: Injury was induced in an atherosclerotic mouse model (ApoE^-/-) or C57BL/6J wild-type (WT) mice through 70% clamping for 1 hour and analyzed after 6 hours of reperfusion.

Results: Elevated serum levels of aspartate and alanine aminotransferase, along with histological assessment, indicated considerable damage in the livers of ApoE^-/- mice than that in WT mice. This indicates a substantial contribution of atherosclerosis to IRI. Furthermore, T and natural killer (NK) cells in ApoE^-/- mouse livers displayed a more inflammatory phenotype than those in WT mouse livers. Reverse transcription-polymerase chain reaction analysis revealed a significant upregulation of interleukin (IL)-15 and its transcriptional regulator, interferon regulatory factor-1 (IRF-1) in ApoE^-/- mouse livers compared with that in WT mouse livers.

Conclusions: These findings suggest that in an atherosclerotic mouse model, atherosclerosis can mirror intrahepatic immunity, particularly activating liver NK and T cells through IL-15 production, thereby exacerbating hepatic damage. The upregulation of IL-15 expression is associated with IRF-1 overexpression.