Phosphoinositide-Specific Phospholipase C Enzymes and Cognitive Development and Decline

The development of the mammalian nervous system is a tightly regulated and complex process, which involves a number of signal transduction pathways, which control the cascade of events, both spatially and temporally. Complex modifications of the structural and functional bases of the activities of the nervous system also occur in the cognitive decline often observed during aging. The Phosphoinositide (PI) signal transduction pathway, which contributes to regulate the calcium levels by means of converting enzymes, such as the Phosphoinositide-specific Phospholipase C (PLC) family, interacts at different hierarchy of control with a number of different molecules and/or pathways involved in neural development, neurogenesis and maintenance of the synaptic plasticity. The PI pathway was suggested to be involved in the complex mechanism of memory, crucial and strictly correlated to learning abilities. Specific roles were also suggested for PLC isoforms, on the basis of numerous evidences indicating the involvement in diseases which affect the nervous system, with special regard to the cognitive impairment. The nature, meaning, and developmental period of PLC involvement in cognitive development and decline are still largely unclear and will require further studies.