eIF5A, or eukaryotic initiation factor 5A, is a protein involved in the process of translation within cells. It plays a role in the initiation, elongation, and termination phases of protein synthesis. eIF5A is unique in that it contains the rare amino acid hypusine, which is formed through a post-translational modification process involving the polyamine pathway. This factor is highly conserved across species and is implicated in various cellular functions beyond translation, such as cell proliferation, development, and response to stress. Recent research has shed light on the broader physiological roles of eIF5A, including its involvement in processes like ischemic tolerance, metabolic adaptation, aging, immune cell differentiation, and even in diseases where oxygen supply is disrupted, like organ transplantation, myocardial infarction, or stroke.