Gut-Liver Axis: Modulating the Gut Microbiota and Its Metabolic Products as a Potential Therapeutic Strategy for the Treatment of Hepatic Ischemia-Reperfusion Injury

Hepatic ischemia-reperfusion injury (HIRI) is a major complication reported in various clinical scenarios such as liver transplantation (LTx), hepatectomy, and acute hepatic insult. This condition affects the restoration of hepatic functionalities post-LTx. Contemporary scientific inquiries have highlighted the involvement of intestinal microbiota and their metabolic by-products in the initiation and progression of HIRI. Perturbations in the gut microbiome, instigated by external stressors such as inflammatory processes, ischemic conditions, and reperfusion events, affect the biosynthesis of metabolites such as short-chain fatty acids (SCFAs), bile acids (BAs), and lipopolysaccharides (LPS). SCFAs can exert anti-inflammatory effects, modulate cellular apoptosis, and attenuate oxidative stress, thereby ameliorating hepatic injury. Other studies have shown that the intestinal microbiota confers hepatoprotective effects by modulating the host's immune response and synthesis of cytokines, controlling inflammation, and enhancing liver protection. This review comprehensively describes the mechanisms underlying the association of gut microbiota and its metabolites with hepatic disease and ischemia-reperfusion injury. The findings from recent studies investigating the gut-liver axis are reviewed to identify therapeutic avenues for the prevention and treatment of liver dysfunction and ischemia-reperfusion injury. In-so-doing, novel pathways and perspectives can be exploited to develop therapies for the control of inflammatory hepatic ischemia-reperfusion injury, particularly following liver transplantation or surgical intervention.