Cytidine is primarily involved in cellular processes related to RNA synthesis and energy transfer. It serves as a building block for RNA, playing a critical role in gene expression and protein synthesis. In medicine, cytidine derivatives are used in antiviral and anticancer therapies. For example, some nucleoside analogs based on cytidine interfere with viral replication or inhibit tumor growth by disrupting DNA and RNA synthesis in infected or cancerous cells. It is also a component of cytidine monophosphate (CMP), which acts as a signaling molecule in phospholipid metabolism, essential for cell membrane formation. Additionally, cytidine is studied for its potential neuroprotective effects and cognitive enhancement, particularly when combined with other compounds like uridine, due to its role in supporting synaptic function and brain health.