Polyamine pathway in neurological disorders: Potential therapeutic implications based on current evidences

Polyamines (PAs) with a positive charge and low molecular weight, are a class of general biogenic amines that are involved in many important cellular processes, including maintaining nucleic acid stability, controlling ion channel activity, regulating transcription and translation, modulating cell cycle, influencing kinase activity, protecting oxidative damage, and maintaining membrane structure. Cumulative studies have shown that in various neurological disorders, the normal synthesis and metabolism of the polyamine pathway would be disrupted. And the changed polyamine system is believed to participate in the pathophysiological process of the disease through various mechanisms, these include down-regulating or up-regulating PA, putrescine, spermidine, spermine, the key enzymes in the polyamine catabolic pathway include ornithine decarboxylase (ODC), spermidine/spermine N1-acetyltransferase (SAT1), and spermine oxidase (SMOX). They also play a role in the disease process by affecting different downstream molecular pathways or mechanisms, resulting in distinct changes under different disease conditions. With such implications of polyamine in the disorder process, targeting the synthesis and metabolism of polyamine system emerges as potential approaches for intervening the neurological disorders. We attempted to explore the potential molecular mechanisms and molecular connections involved in polyamines at first. Then, we describe possible links between polyamines and various neurological disorders, and finally the possible therapeutic implications on targeting the polyamine system for the treatment of various disorders were proposed. This review may provide an up-to-date overview to propose the new perspective about targeting PA for developing potential therapeutic strategies.