Programmed Cell Death-1 (PD-1) Signalling and Neurotransmitter Dynamics: Implications for Neuroprotection

Inhibitors of programmed cell death protein-1 (PD-1) have demonstrated use outside immune system regulation, particularly inside the neurological system. These inhibitors are frequently employed in oncology. Researchers have discovered that PD-1 is expressed in neurons and glia, regulating ion channels, GABAergic and opioid pathways, and neuroinflammation. The ongoing study demonstrates this fact. Some individuals believe that suppressing PD-1 may protect neurons by enhancing their plasticity, thereby boosting cognitive function and altering pain perception. The development of programmed cell death protein 1 (PD-1) inhibitors has transformed cancer immunotherapy. These inhibitors liberate the immune system from its tumour-defence mechanisms, facilitating cancer treatment. Conversely, increasing evidence suggests that PD-1 influences not only the immune system but also the central nervous system (CNS). A recent study has demonstrated that PD-1 and its ligands are found in brain tissues, influencing neurotransmitter pathways, neuronal excitability, and neuroinflammation. This occurs because they influence multiple physiological processes. Innovative PD-1 integration into psychiatry opens new avenues for modulating neuroimmune interactions linked to psychiatric diseases, highlighting immune checkpoint pathways as potential therapeutic targets beyond neurotransmitter systems. Precision medicine now includes neuropsychiatric illnesses by modulating the immune system to improve brain health and mental symptoms. This study aims to assess current knowledge of the protective effects of PD-1 inhibitors on neurons. The analysis considers experimental and clinical evidence for neuroprotection, its limits, and potential future therapeutic applications. It is essential to consider how these inhibitors affect neurotransmitter systems. This study examines the potential pros and cons of using PD-1 inhibitors for the treatment of neurological diseases. This study needs to conduct further research to understand how these inhibitors can fully protect the brain.