Molecular Mechanisms, Dynamic Lesions, and Therapeutic Targets in Intestinal Ischemia–Reperfusion Injury: A Systematic Review

Intestinal ischemia-reperfusion injury (IRI) represents a major cause of morbidity and mortality in abdominal surgery, trauma, and intestinal transplantation. The pathophysiological process involves a biphasic cascade that begins with ischemic hypoxia and progresses to amplified cellular and molecular injury upon reperfusion. This review synthesizes recent mechanistic insights regarding endothelial and microvascular dysfunction, epithelial barrier breakdown, microbiota-driven systemic propagation, and the involvement of oxidative/nitrosative stress and inflammatory signaling. The novelty of our review's approach is the focus on experimental and translational studies and correlation of the data with future directions for mechanistic research and clinical implementation. Despite promising preclinical results, heterogeneity in study protocols or/and model limitations make clinical translation challenging. Recent studies have demonstrated that mitochondria, tight junction proteins, adhesion molecules and innate immune receptors are critical determinants of lesion evolution. Based on these, the current therapeutic strategies include antioxidants, adenosine pathway modulators, dexmedetomidine, ischemic conditioning, hyperbaric oxygen therapy, and microbiota-targeted interventions. Since each mechanism is acting on distinct molecular pathways, a multimodal therapy that integrates redox modulation, endothelial protection, microbiome regulation, and the identification and employment of precision biomarkers is likely to improve outcomes. Beyond summarizing established molecular mechanisms, this review critically reassesses why decades of promising experimental strategies for intestinal ischemia-reperfusion injury has largely failed to translate into effective clinical therapies. By distinguishing context-dependent mechanisms from pathways with consistent translational relevance, we highlight key methodological and biological barriers limiting clinical applicability. Furthermore, we propose a temporally structured, multimodal therapeutic framework that integrates phase-specific pathophysiology with targeted interventions, aiming to inform future experimental design and improve translational success.