Non-steroidal anti-inflammatory drugs have anti-amyloidogenic effects for Alzheimer's β-amyloid fibrils in vitro

The pathogenesis of Alzheimer's disease (AD) is characterized by cerebral deposits of amyloid beta-peptides (AP) and neurofibrillary tangles which are surrounded by inflammatory cells. Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) reduces the risk of. developing AD and delays the onset of the disease. In the present study, we used fluorescence spectroscopy with thioflavin T and electron microscopy to examine the effects of NSAIDs such as ibuprofen, aspirin, meclofenamic acid sodium salt, diclofenac sodium salt, ketoprofen, flurbiprofen, naproxen, sulindac sulfide and indomethacin on the formation, extension, and destabilization of beta-amyloid fibrils (fA beta) at pH 7.5 at 37 degrees C in vitro. All examined NSAIDs dose-dependently inhibited formation of fA beta from fresh A beta(1-40) and A beta(1-42), as well as their extension. Moreover, these NSAIDs dose-dependently destabilized preformed fA beta s. The overall activity of the molecules examined was in the following order: ibuprofen approximate to sulindac sulfide >= meclofenamic acid sodium salt > aspirin approximate to ketoprofen >= flurbiprofen approximate to diclofenac sodium salt > naproxen approximate to indomethacin. Although the mechanisms by which these NSAIDs inhibit fA beta formation from A beta, and destabilize preformed fA beta in vitro are still unclear, NSAIDs may be promising for the prevention and treatment of AD. (c) 2005 Elsevier Ltd. All rights reserved.