Adenosine deaminase, not immune to a mechanistic rethink in central nervous system disorders?

Adenosine deaminase (ADA) is a purine metabolism enzyme that catalyses the breakdown of adenosine and deoxyadenosine. The enzyme is important in several cellular processes, including the innate immune response and cellular differentiation, and it is also an important enzyme for the maintenance of brain homeostasis, in part due to its regulation of adenosine. Aberrant regulation of ADA enzyme activity has been l i nked t o several neurodegenerat i ve di seases and diseases that can result in neurological impairment. However, t he mechani sms behi nd al t er ed ADA regulation and how this leads to the development of neurological dysfunction are poorly characterised. This review summarises the current research on ADA and its role and regulation in disease pathology, with a focus on t he cent r al ner vous syst em ( CNS) and t he neurodegenerative disease, amyotrophic lateral sclerosis (ALS).