Dual Functions of Polyamines in Shaping Host-Specific Pathogen Dynamics

Polyamines such as putrescine, spermidine, and spermine play essential roles in most living organisms. They regulate fundamental processes, like cell proliferation, differentiation, growth, gene expression (DNA/RNA stability, transcription, and translation), and signal transduction. As important regulators, polyamines influence development, stress responses, and the progression of health and disease, including cancer and aging. These positively charged molecules have been extensively studied for decades. In humans, polyamines are often researched as potential therapeutic targets for diseases such as malaria and, more recently, COVID-19. Obligate parasites, such as Plasmodium falciparum, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rely on host cellular machinery for survival, replication, and growth. Notably, both hosts and pathogens need polyamines to sustain these processes. This review summarizes current advances in understanding the roles of polyamines in humans, viruses, and obligate parasites. It also explores strategies to prevent pathogens from hijacking host polyamine metabolism as a way toward developing novel therapeutic interventions.