Phosphopeptidome specific kinase inhibitor profiling of 2 Alzheimer's disease modifying compounds Withaferin A and Saracatinib AZD0530.

Alzheimer's dementia (AD) is increasingly being recognized as one of the most important medical and social problems in older people in industrialized and non-industrialized nations. Sofar, little is known about possible changes in protein kinase activity in the pathology of AD progression. Today, kinase inhibitors upstream or downstream of amyloid-β oligomer signaling hold promise as effective disease modifying strategies to attenuate or prevent AD progression. In this respect, there is an urgent need to investigate changes in protein kinase activity and the associated signalling pathways during AD progression and the potential of these kinases to be used as diagnostic biomarkers and drug targets. The low benefit of drugs which target one single kinase has enforced research towards multitargeting kinase inhibitor strategies in AD drug-discovery and to develop brain-permeable multitargeting protein kinase inhibitors with low cellular toxicity which attenuate protein kinase hyperactivity but do not block their physiological activity levels in normal cells. In preliminar studiesIn preliminar kinome activity profiling studies in cortex of different AD mice models (at the preplaque stage), we observed significant hyperactivation of Abl and Src (Fyn,Lck) kinase activities, related to neuroinflammation and neuronal cell survival/cell death. In the current proposal we want to apply phosphopeptidome profiling in the transgenic AD model APP23 to determine the kinome inhibitor profile of 2 promising AD modulator compounds withaferin A and saracatinib AZD0530 which have already shown to attenuate and/or reverse AD pathology: - we have purified and characterized a novel class of withaferin A related kinase inhibitors from Withania Somnifera (also known as "ashwagandha" in Ayurvedic medicine) which is able to reverse behavioral deficits, plaque pathology, accumulation of β-amyloid peptides (Aβ) and oligomers in the brains of middle-aged and old Alzheimer's disease transgenic mice. Briefly, these blood-brain permeable compounds promote cognition-memory and help to promote neurite outgrowth in cultured neurons and in rodents injected with Aβ . - In another study, the pharmacological src/fyn kinase inhibitor and cancer drug saracatinib AZD0530 was repurposed as a promising candidate for treatment of AD, since it was found to rescue established memory and synapse loss in a preclinical mouse model of Alzheimer disease upon kinase inhibition Moreover, AZD0530 is reasonably safe and well tolerated in patients with mild-to-moderate AD, achieving substantial central nervous system penetration in clinical trials. Recent reports support a role for kinase therapy as an effective disease modifying strategy in Alzheimer disease (AD). Peptide array based kinase activity (Pamchip) profiling is an innovative approach to reveal previously unknown kinase networks involved in AD pathology. It can lead to the discovery of novel diagnostic kinase biomarkers and druggable targets for treatment of AD disease . In this proposal we will identify kinase activity changes related to AD progression in a transgenic AD mouse model by Pamchip kinase activity profiling. Moreover, we will characterize the kinase inhibitor profile of Withaferin A and Saracatinib which are able to reverse AD pathology. This proposal wil contribute in development of a disease-modifying kinase therapy in AD which can revolutionize the care of millions of patients worldwide, with a major impact on rapidly escalating healthcare costs.

Keywords:ALZHEIMER'S DISEASE

Disciplines:Cell signalling, Systems biology not elsewhere classified, Cognitive neuroscience, Compound screening, In vitro testing, Non-clinical studies