Inhibitors of tau-phosphorylating kinases

The phosphorylation of tau protein is finely regulated by a balance between phosphorylation and dephosphorylation processes carried out by kinases and phosphatases. It has been suggested that the disruption of this equilibrium and consequent abnormal tau phosphorylation contribute to the aggregation of tau. The understanding of this important mechanism is of high interest because of the implication of tau aggregates in the development of Alzheimer’s disease (AD). In the last few years, among the possible strategies which could be used to reduce tau phosphorylation, the inhibition of certain tyrosine kinases has been suggested as a promising alternative to the common therapeutic approaches. In this chapter we will first give an overview of the tau protein kinases, their roles in cells, regulation and importance in AD. This will be followed by a more detailed description of the role of Fyn, a member of the Src family kinases, in the physiological development of CNS and the pathological progress of AD. How the inhibition of Fyn could be used as a new strategy in the fight against AD will be discussed.