title: Involvement of phosphoinositide 3-kinase gamma in the neuro-inflammatory response and cognitive impairments induced by beta-amyloid 1-40 peptide in mice.
abstract: Alzheimer disease (AD) is the most common form of dementia in the elderly, and the neuro-pathological hallmarks of AD include neurofibrillary tangles (NFT), and deposition of beta-amyloid (Abeta) in extracellular plaques. In addition, chronic inflammation due to recruitment of activated glial cells to amyloid plaques are an invariant component in AD, and several studies have reported that the use of non-steroidal anti-inflammatory drugs (NSAIDs) may provide a measure of protection against AD. In this report we have investigated whether phosphoinositide 3-kinase gamma (PI3Kgamma), which is important in inflammatory cell migration, plays a critical role in the neuro-inflammation, synaptic dysfunction, and cognitive deficits induced by intracerebroventricular injection of Abeta(1-40) in mice. We found that the selective inhibitor of PI3Kgamma, AS605240, was able to attenuate the Abeta(1-40)-induced accumulation of activated astrocytes and microglia in the hippocampus, and decrease immuno-staining for p-Akt and cyclooxygenase-2 (COX-2). Interestingly, Abeta(1-40) activated macrophages treated with AS605240 or another PI3Kgamma inhibitor, AS252424, displayed impaired chemotaxis in vitro, but their expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) was unaffected. Finally, AS605240 prevented Abeta(1-40)-induced cognitive deficits and synaptic dysfunction, but failed to modify scopolamine-induced amnesia. Our data suggests that inhibition of PI3Kgamma may represent a novel therapeutic target for treating AD patients.
authors.affiliation: Departamento de Farmacologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Giselle F
authors.initials: GF
authors.lastname: Passos
authors.forename: Cláudia P
authors.initials: CP
authors.lastname: Figueiredo
authors.forename: Rui D S
authors.initials: RD
authors.lastname: Prediger
authors.forename: Kathryn A B S
authors.initials: KA
authors.lastname: Silva
authors.forename: Jarbas M
authors.initials: JM
authors.lastname: Siqueira
authors.forename: Filipe S
authors.initials: FS
authors.lastname: Duarte
authors.forename: Paulo C
authors.initials: PC
authors.lastname: Leal
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Medeiros
authors.forename: João B
authors.initials: JB
authors.lastname: Calixto
mesh_terms: D016229:Amyloid beta-Peptides / Q000633:toxicity*; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D058544:Class Ib Phosphatidylinositol 3-Kinase; D003071:Cognition / Q000187:drug effects*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D053583:Interleukin-1beta / Q000378:metabolism; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D009443:Neuritis / Q000139:chemically induced / Q000201:enzymology* / Q000523:psychology*; D009457:Neuroglia / Q000187:drug effects / Q000276:immunology; D010446:Peptide Fragments / Q000633:toxicity*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D013569:Synapses / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D058544:Class Ib Phosphatidylinositol 3-Kinase; D051546:Cyclooxygenase 2; D004791:Enzyme Inhibitors; D053583:Interleukin-1beta; D007527:Isoenzymes; D010446:Peptide Fragments; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt; D014409:Tumor Necrosis Factor-alpha; C078592:amyloid beta-protein (1-40); C546764:Pik3cg protein, mouse