Knowledge of signal transduction provides an approach to attacking memory decline

Abstract

Memory, the basis of higher cognitive functions, has been a major topic of interest for a very long time. One of the major setbacks most of us face as we age is a decline in declarative memory, which mainly depends on a brain structure called the hippocampus. Because memory decline has such a negative impact on quality of our life, intense efforts are being directed toward finding therapeutic interventions to ameliorate or even prevent memory decline. A major focus is on molecular targets to improve or maintain memory. Through the knowledge obtained from extensive study of amnesic patients and rapid progress in modern biochemical and neurosciences, the molecular mechanisms underpinning learning and memory and neural plasticity in the central nervous system have been revealed. In this review, we present a brief summary of memory characteristics in psychological terms, followed by a discussion of the basic concept of the memory system, its underlying cellular mechanisms, and age-related decline in memory. Antidementia drugs developed on the basis of the cholinergic hypothesis are also discussed. Finally, we assess the use of phosphodiesterase inhibitors, which control the cAMP-PKA-CREB signal transduction pathway, as potential candidates for treating memory decline beyond the existing cholinergic-based strategies.