Isolongifolene Alleviates Liver Ischemia/Reperfusion Injury by Regulating AMPK-PGC1α Signaling Pathway-Mediated Inflammation, Apoptosis, and Oxidative Stress

Abstract

Isolongifolene (ISO) has antioxidant, anti-inflammatory, anticancer, and neuroprotective effects; however, it is unclear whether isolongifolene has a protective effects against liver ischemia/reperfusion (I/R) injury. In this study, a mouse liver I/R injury model and a mouse AML12 cell Hypoxia reoxygenation (H/R) model were established after pretreatment with different concentrations of isolongifolene. Serum transaminase levels, necrotic liver area, cell activity, inflammation response, oxidative stress, and apoptosis were used to evaluate the effect of isolongifolene on liver I/R or cell H/R injury. Western blotting was used to detect Bax, Bcl-2, C-Caspase3, AMPK, P-AMPK, and PGC1α protein expression levels. The AMPK inhibitor, compound C, was used to inhibit the AMPK expression. The results showed that isolongifolene reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, liver necrosis, inflammatory factors IL-1β, IL-6, MCP-1, and TNF-α expression, MPO⁺ inflammatory cell infiltration, MDA content, TUNEL-positive cell number, cell apoptosis rate, and the expression of pro-apoptotic proteins Bax and C-Caspase3, while increasing cell viability, SOD and GSH activity, and the expression of anti-apoptotic protein Bcl-2. Moreover, Western blotting results showed that isolongifolene could increase the protein expression of P-AMPK and PGC1α. Following the addition of compound C, the protective effect of isolongifolene was significantly weakened. Therefore, our results suggest that isolongifolene alleviates liver I/R injury by regulating AMPK-PGC1α signaling pathway-mediated anti-inflammatory, and antioxidant and anti-apoptotic effects.

Note:
Funding Information: This work was supported by the Youth Fund of the First Affiliated Hospital of Zhengzhou University (NO. 71284).

Declaration of Interests: The authors declare no competing interests.

Ethics Approval Statement: The mice were cared for in accordance with the National Institutes of Health Guide for Laboratory Animals. Animal experiments were approved by the Ethics Committee of the Affiliated Hospital of Zhengzhou University.

Keywords: Liver ischemia/reperfusion injury, Isolongifolene, AMPK-PGC1α pathway, inflammation, Apoptosis, oxidative stress