Effects of Tacrolimus on Cognitive Functions of the Central Nervous System: A Review Article

Abstract

BACKGROUND AND OBJECTIVE: Tacrolimus belongs to the family of calcineurin inhibitors and is extensively used as an immunosuppressive drug after allogeneic organ transplant. According to the inhibitory effects of calcineurin on synaptic plasticity and memory functions, it seems that the administration of tacrolimus leads to changes in the electrophysiological responses and memory functions. Therefore, this article includes studies in which tacrolimus involvement in cognitive functions such as synaptic plasticity, learning and memory are investigated, and the possible mechanism of the effect of tacrolimus on synaptic plasticity and memory are explained. METHODS: In this narrative review article, we searched PubMed and Google Scholar databases using the keyword “Tacrolimus”, “Calcineurin”, “Synaptic Plasticity”, “Learning”, “Memory”, and “Free radicals” to provide an overview of effects of tacrolimus on cognitive functions. Finally, articles published on these topics between 1987 and 2021 were investigated. FINDINGS: Among the 5632 sources found, 72 articles were considered appropriate for the purpose of the research. Findings support that the administration of tacrolimus (TAC) improves cognitive functions such as learning, memory, and synaptic plasticity. Furthermore, TAC has neuroprotective effects against oxidative stress-mediated cognitive dysfunctions. CONCLUSION: The results of the study showed that TAC may improve learning, memory, and synaptic plasticity, possibly by calcineurin inhibition, reducing the level of free radicals, and altering calcium and glutamate levels.