Generation of Aβ38 and Aβ42 Is Independently and Differentially Affected by Familial Alzheimer Disease-associated Presenilin Mutations and γ-Secretase Modulation

Alzheimer disease amyloid β-peptide (Aβ) is generated via proteolytic processing of the β-amyloid precursor protein by β- and γ-secretase. γ-Secretase can be blocked by selective inhibitors but can also be modulated by a subset of non-steroidal anti-inflammatory drugs, including sulindac sulfide. These drugs selectively reduce the generation of the aggregation-prone 42-amino acid Aβ42 and concomitantly increase the levels of the rather benign Aβ38. Here we show that Aβ42 and Aβ38 generation occur independently from each other. The amount of Aβ42 produced by cells expressing 10 different familial Alzheimer disease (FAD)-associated mutations in presenilin (PS) 1, the catalytic subunit of γ-secretase, appeared to correlate with the respective age of onset in patients. However, Aβ38 levels did not show a negative correlation with the age of onset. Modulation of γ-secretase activity by sulindac sulfide reduced Aβ42 in the case of wild type PS1 and two FAD-associated PS1 mutations (M146L and A285V). The remaining eight PS1 FAD mutants showed either no reduction of Aβ42 or only rather subtle effects. Strikingly, even the mutations that showed no effect on Aβ42 levels allowed a robust increase of Aβ38 upon treatment with sulindac sulfide. Similar observations were made for fenofibrate, a compound known to increase Aβ42 and to decrease Aβ38. For mutants that predominantly produce Aβ42, the ability of fenofibrate to further increase Aβ42 levels became diminished, whereas Aβ38 levels were altered to varying extents for all mutants analyzed. Thus, we conclude that Aβ38 and Aβ42 production do not depend on each other. Using an independent non-steroidal anti-inflammatory drug derivative, we obtained similar results for PS1 as well as for PS2. These in vitro results were confirmed by in vivo experiments in transgenic mice expressing the PS2 N141I FAD mutant. Our findings therefore have strong implications on the selection of transgenic mouse models used for screening of the Aβ42-lowering capacity of γ-secretase modulators. Furthermore, human patients with certain PS mutations may not respond to γ-secretase modulators. Alzheimer disease amyloid β-peptide (Aβ) is generated via proteolytic processing of the β-amyloid precursor protein by β- and γ-secretase. γ-Secretase can be blocked by selective inhibitors but can also be modulated by a subset of non-steroidal anti-inflammatory drugs, including sulindac sulfide. These drugs selectively reduce the generation of the aggregation-prone 42-amino acid Aβ42 and concomitantly increase the levels of the rather benign Aβ38. Here we show that Aβ42 and Aβ38 generation occur independently from each other. The amount of Aβ42 produced by cells expressing 10 different familial Alzheimer disease (FAD)-associated mutations in presenilin (PS) 1, the catalytic subunit of γ-secretase, appeared to correlate with the respective age of onset in patients. However, Aβ38 levels did not show a negative correlation with the age of onset. Modulation of γ-secretase activity by sulindac sulfide reduced Aβ42 in the case of wild type PS1 and two FAD-associated PS1 mutations (M146L and A285V). The remaining eight PS1 FAD mutants showed either no reduction of Aβ42 or only rather subtle effects. Strikingly, even the mutations that showed no effect on Aβ42 levels allowed a robust increase of Aβ38 upon treatment with sulindac sulfide. Similar observations were made for fenofibrate, a compound known to increase Aβ42 and to decrease Aβ38. For mutants that predominantly produce Aβ42, the ability of fenofibrate to further increase Aβ42 levels became diminished, whereas Aβ38 levels were altered to varying extents for all mutants analyzed. Thus, we conclude that Aβ38 and Aβ42 production do not depend on each other. Using an independent non-steroidal anti-inflammatory drug derivative, we obtained similar results for PS1 as well as for PS2. These in vitro results were confirmed by in vivo experiments in transgenic mice expressing the PS2 N141I FAD mutant. Our findings therefore have strong implications on the selection of transgenic mouse models used for screening of the Aβ42-lowering capacity of γ-secretase modulators. Furthermore, human patients with certain PS mutations may not respond to γ-secretase modulators. Alzheimer disease is the most abundant form of dementia, and increasing numbers of patients are to be expected in the near future. Amyloid β-peptide (Aβ) 5The abbreviations used are:Aβamyloid β-peptideAPPβ-amyloid precursor proteinFADfamilial Alzheimer diseaseNSAIDnon-steroidal anti-inflammatory drugPSpresenilinWTwild typeHEKhuman embryonic kidneyMALDI-TOFmatrix-assisted laser desorption ionization time-of-flightMSmass spectrometryGSM-1γ-secretase modulator 1. is a central player in the disease pathology. Originally it was purified as the building block of the disease-defining amyloid plaques. Now it is becoming clear that amyloid plaques are probably not the major neurotoxic entity in the disease rather this is an assembly of soluble oligomeric Aβ species (1Haass C. Selkoe D.J. Nat. Rev. Mol. Cell Biol. 2007; 8: 101-112Crossref PubMed Scopus (3998) Google Scholar). These assemblies initiate the so-called amyloid cascade and finally induce abnormal phosphorylation of tau and subsequent formation of paired helical filaments (2Hardy J. Selkoe D.J. Science. 2002; 297: 353-356Crossref PubMed Scopus (11347) Google Scholar). Aβ is generated by proteolytic processing of the β-amyloid precursor protein (APP). Two proteases, β-secretase andγ-secretase, perform the cleavages on the N and C termini of the Aβ domain, respectively (3Haass C. EMBO J. 2004; 23: 483-488Crossref PubMed Scopus (494) Google Scholar). β-Secretase is a conventional aspartyl protease, whereas γ-secretase is a rather unusual aspartyl protease capable of intramembraneous cleavage by utilization of a novel active site (4Wolfe M.S. Xia W. Ostaszewski B.L. Diehl T.S. Kimberly W.T. Selkoe D.J. Nature. 1999; 398: 513-517Crossref PubMed Scopus (1714) Google Scholar) that is signified by a highly conserved GXGD motif that includes one of the two active site aspartyl residues (5Steiner H. Kostka M. Romig H. Basset G. Pesold B. Hardy J. Capell A. Meyn L. Grim M.G. Baumeister R. Fechteler K. Haass C. Nat. Cell Biol. 2000; 2: 848-851Crossref PubMed Scopus (256) Google Scholar). γ-Secretase is a complex composed of four subunits, presenilin 1 (PS1) or PS2, APH-1a or APH-1b, PEN-2, and nicastrin. PS harbors the catalytically active center of the protease. Numerous familial Alzheimer disease (FAD)-associated mutations occur within the PSs. They all increase the Aβ42/Aβ40 ratio. Since Aβ42 aggregates much faster than Aβ40, these mutations affect the kinetics of oligomer formation and aggregation (1Haass C. Selkoe D.J. Nat. Rev. Mol. Cell Biol. 2007; 8: 101-112Crossref PubMed Scopus (3998) Google Scholar). amyloid β-peptide β-amyloid precursor protein familial Alzheimer disease non-steroidal anti-inflammatory drug presenilin wild type human embryonic kidney matrix-assisted laser desorption ionization time-of-flight mass spectrometry γ-secretase modulator 1. Pharmacological inhibition of the secretases is a major therapeutic task. Unfortunately, the development of β-secretase inhibitors seems to be rather complicated (6Citron M. Nat. Rev. Neurosci. 2004; 5: 677-685Crossref PubMed Scopus (416) Google Scholar), and γ-secretase inhibitors caused major side effects in animal models and during clinical trials, due to the reduction of the biological function of γ-secretase in Notch signaling (3Haass C. EMBO J. 2004; 23: 483-488Crossref PubMed Scopus (494) Google Scholar). However, modulators of γ-secretase activity, namely a subset of the nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or sulindac sulfide, selectively reduce the production of the aggregation-prone Aβ42 while leaving Notch signaling intact (7Beher D. Clarke E.E. Wrigley J.D. Martin A.C. Nadin A. Churcher I. Shearman M.S. J. Biol. Chem. 2004; 279: 43419-43426Abstract Full Text Full Text PDF PubMed Scopus (191) Google Scholar, 8Eriksen J.L. Sagi S.A. Smith T.E. Weggen S. Das P. McLendon D.C. Ozols V.V. Jessing K.W. Zavitz K.H. Koo E.H. Golde T.E. J. Clin. Investig. 2003; 112: 440-449Crossref PubMed Scopus (0) Google Scholar, 9Weggen S. Eriksen J.L. Sagi S.A. Pietrzik C.U. Golde T.E. Koo E.H. J. Biol. Chem. 2003; 278: 30748-30754Abstract Full Text Full Text PDF PubMed Scopus (135) Google Scholar, 10Weggen S. Eriksen J.L. Das P. Sagi S.A. Wang R. Pietrzik C.U. Findlay K.A. Smith T.E. Murphy M.P. Bulter T. Kang D.E. Marquez-Sterling N. Golde T.E. Koo E.H. Nature. 2001; 414: 212-216Crossref PubMed Scopus (1346) Google Scholar). Concomitantly, they increase Aβ38 production (10Weggen S. Eriksen J.L. Das P. Sagi S.A. Wang R. Pietrzik C.U. Findlay K.A. Smith T.E. Murphy M.P. Bulter T. Kang D.E. Marquez-Sterling N. Golde T.E. Koo E.H. Nature. 2001; 414: 212-216Crossref PubMed Scopus (1346) Google Scholar). Therefore, there seems to be an equilibrium of Aβ42 and Aβ38 generation. Moreover, compounds such as fenofibrate, which are known to exhibit an opposite modulating activity by increasing Aβ42 production, reduce Aβ38 production (11Kukar T. Murphy M.P. Eriksen J.L. Sagi S.A. Weggen S. Smith T.E. Ladd T. Khan M.A. Kache R. Beard J. Dodson M. Merit S. Ozols V.V. Anastasiadis P.Z. Das P. Fauq A. Koo E.H. Golde T.E. Nat. Med. 2005; 11: 545-550Crossref PubMed Scopus (260) Google Scholar), again suggesting an interdependence of Aβ42 and Aβ38 production. NSAIDs most likely modulate γ-secretase activity directly, because they are active in cell-free assays (7Beher D. Clarke E.E. Wrigley J.D. Martin A.C. Nadin A. Churcher I. Shearman M.S. J. Biol. Chem. 2004; 279: 43419-43426Abstract Full Text Full Text PDF PubMed Scopus (191) Google Scholar, 8Eriksen J.L. Sagi S.A. Smith T.E. Weggen S. Das P. McLendon D.C. Ozols V.V. Jessing K.W. Zavitz K.H. Koo E.H. Golde T.E. J. Clin. Investig. 2003; 112: 440-449Crossref PubMed Scopus (0) Google Scholar, 12Takahashi Y. Hayashi I. Tominari Y. Rikimaru K. Morohashi Y. Kan T. Natsugari H. Fukuyama T. Tomita T. Iwatsubo T. J. Biol. Chem. 2003; 278: 18664-18670Abstract Full Text Full Text PDF PubMed Scopus (197) Google Scholar, 13Weggen S. Eriksen J.L. Sagi S.A. Pietrzik C.U. Ozols V. Fauq A. Golde T.E. Koo E.H. J. Biol. Chem. 2003; 278: 31831-31837Abstract Full Text Full Text PDF PubMed Scopus (281) Google Scholar, 14Fraering P.C. Ye W. Strub J.M. Dolios G. LaVoie M.J. Ostaszewski B.L. van Dorsselaer A. Wang R. Selkoe D.J. Wolfe M.S. Biochemistry. 2004; 43: 9774-9789Crossref PubMed Scopus (205) Google Scholar) and they are known to affect the conformation of PS probably by an allosteric mechanism (15Lleo A. Berezovska O. Herl L. Raju S. Deng A. Bacskai B.J. Frosch M.P. Irizarry M. Hyman B.T. Nat. Med. 2004; 10: 1065-1066Crossref PubMed Scopus (205) Google Scholar). Moreover, their modulating activity in terms of Aβ42 reduction is affected by some FAD-associated PS1 mutations. The PS1 Δexon9 mutation decreases the sensitivity of the γ-secretase to sulindac sulfide, whereas the PS1 M146L mutation enhances its sensitivity (13Weggen S. Eriksen J.L. Sagi S.A. Pietrzik C.U. Ozols V. Fauq A. Golde T.E. Koo E.H. J. Biol. Chem. 2003; 278: 31831-31837Abstract Full Text Full Text PDF PubMed Scopus (281) Google Scholar). We now investigated the equilibrium of Aβ38 and Aβ42 generation in cells expressing wild type (WT) PS or FAD-associated PS mutations as well as in transgenic mice expressing WT PS2 or a FAD-associated PS2 mutation. Surprisingly, we found that Aβ38 and Aβ42 generation do not depend on each other. Moreover, Aβ38 and Aβ42 respond differentially to γ-secretase modulation depending on the PS mutation expressed. Antibodies—Monoclonal antibodies against the PS1 N terminus (PS1N) and against the PS2 large loop (BI.HF5c), as well as the poly- and monoclonal antibodies to Aβ (3552, 2D8), were described previously (16Shirotani K. Tomioka M. Kremmer E. Haass C. Steiner H. Neurobiol. Dis. 2007; 27: 102-107Crossref PubMed Scopus (67) Google Scholar). The C-terminal-specific anti-Aβ38 antibody was obtained from Meso Scale Discovery, and C-terminal-specific anti-Aβ40 (BAP24) and anti-Aβ42 (BAP15) antibodies were a kind gift from Dr. Manfred Brockhaus (Roche Applied Science). cDNA Constructs—cDNA constructs encoding PS1 and PS2 FAD mutants were generated by PCR-mediated mutagenesis using oligonucleotide primers encoding the respective mutations and cloned into pcDNA3.1/zeo(+) (Invitrogen). Cell Culture—Human embryonic kidney (HEK) 293 cells stably co-expressing Swedish mutant APP (HEK293/sw) together with the indicated PS variant were cultured as described before (17Moehlmann T. Winkler E. Xia X. Edbauer D. Murrell J. Capell A. Kaether C. Zheng H. Ghetti B. Haass C. Steiner H. S. A. 2002; PubMed Scopus Google Scholar). cells were stably with the indicated PS using to the of stably PS cells were investigated to were a of in and for cells were in of either sulindac sulfide fenofibrate (Roche Applied or for before of by were in and all were in for Aβ40, and PS were obtained with protease inhibitors by for were by and PS was by of Aβ species was as described previously A. M. S. J. N. T. K. Y. T. K. T. T. H. A. Haass C. M. Biochemistry. PubMed Scopus Google Scholar). Aβ species were from from each with antibody for were four with 10 and two with were with acid in with The were on a and to using of Aβ in were by a using the Meso Scale were blocked in in and with antibody in were with before the of and Aβ C-terminal-specific anti-Aβ38 Scale anti-Aβ40 or anti-Aβ42 (BAP24) antibodies were in and used as were for before with and with For Meso Scale was and the was using the Meso Scale The of Aβ were using the Meso Scale of each Aβ species as a of Aβ Aβ40, and were and were using the and γ-secretase I. D. J.D. J.L. Clarke E.E. A. T. L. E. S. P. R. M. D.E. Shearman M.S. S. Wrigley J.D. Med. Chem. PubMed Scopus Google Scholar, J.D. Churcher I. M. P. C. T. Shearman M.S. J. PubMed Scopus Google Scholar, J.D. Smith M.A. R. S. N. C. Churcher I. T. Shearman M.S. J. 2007; PubMed Scopus Google Scholar) was from the by J. Churcher A. P. A. D. M. B. and S. Scholar) and Churcher A. A. D. and S. Scholar). The γ-secretase modulator was from the by J. J. M. and E. M. Scholar). compounds were in and by a of 10 for L. B. P. Brockhaus M. H. C. G. H. H. J. Neurosci. 2003; 23: PubMed Google Scholar) and mice for and mutant N141I L. M. A. P. P. C. Brockhaus M. T. H. Dis. 2005; 2: PubMed Scopus Google Scholar) were used in these these the of human and human mutant PS2 is by the and respectively L. B. P. Brockhaus M. H. C. G. H. H. J. Neurosci. 2003; 23: PubMed Google Scholar). were with mice because this age Aβ is in a soluble form M. G. R. L. 2005; PubMed Scopus Google Scholar). were a of the drugs or were and on of soluble in vivo experiments were in to the on animal and to the of the for and of and of of Aβ40, Aβ42, and were in of for on and were and Aβ levels were using the as described in R. Haass C. Steiner H. B. K. J. Med. Chem. PubMed Scopus Google Scholar). Aβ42 and Aβ38 production is we investigated 10 PS1 mutations. were that a of disease in the case of the PS1 M146L and mutations to than in the case of the PS1 and cDNA constructs encoding PS1 mutations as well as WT PS1 were stably into cells stably expressing Swedish mutant APP to of Aβ Cell were investigated for the of PS2, which as an for of PS1 G. L. G. T. C. M. Hardy J. Full Text Full Text PDF PubMed Scopus Google Scholar). in PS2 was by of all PS1 mutations. to PS1 for all each case PS1 was with the of PS1 which is known not to proteolytic processing G. L. G. T. C. M. Hardy J. Full Text Full Text PDF PubMed Scopus Google Scholar) We the levels of Aβ40, and the PS1 mutations a of effects on Aβ42 production. can from a rather as in the case of the PS1 M146L to a increase as in the case of the PS1 and mutations with findings (17Moehlmann T. Winkler E. Xia X. Edbauer D. Murrell J. Capell A. Kaether C. Zheng H. Ghetti B. Haass C. Steiner H. S. A. 2002; PubMed Scopus Google Scholar), the increase of Aβ42 production seems to occur the of Aβ40, because these levels decrease with Aβ42 These findings are also with an correlation of Aβ42 levels with age of onset M. J. T. Neurobiol. 2005; PubMed Scopus Google Scholar). Aβ38 levels to show negative correlation to Aβ42 levels in suggesting that Aβ42 is generated independently of Aβ38. Aβ species with C termini than or not be by the we also investigated Aβ species by mass spectrometry some species such as and were upon of certain Aβ40, and Aβ42 were the most abundant species for the of mutants further Aβ38 and Aβ42 production are to each we cells with the sulindac sulfide. sulfide is known to modulate γ-secretase activity by the cleavage from acid to acid (10Weggen S. Eriksen J.L. Das P. Sagi S.A. Wang R. Pietrzik C.U. Findlay K.A. Smith T.E. Murphy M.P. Bulter T. Kang D.E. Marquez-Sterling N. Golde T.E. Koo E.H. Nature. 2001; 414: 212-216Crossref PubMed Scopus (1346) Google Scholar). with the PS1 M146L mutation showed sensitivity to treatment with sulindac sulfide, whereas the PS1 Δexon9 and PS1 mutations to respond to the Aβ42-lowering activity (13Weggen S. Eriksen J.L. Sagi S.A. Pietrzik C.U. Ozols V. Fauq A. Golde T.E. Koo E.H. J. Biol. Chem. 2003; 278: 31831-31837Abstract Full Text Full Text PDF PubMed Scopus (281) Google Scholar, E. S. C. A. M. Koo E.H. Pietrzik C.U. K. Weggen S. J. Biol. Chem. 2007; Full Text Full Text PDF PubMed Scopus Google Scholar) Furthermore, all mutations with the of PS1 showed only of Aβ42 levels that these mutations γ-secretase to the modulating activity of sulindac sulfide. However, we investigated the levels of we found that all PS1 including that showed no reduction of Aβ42 upon sulindac sulfide treatment such as PS1 and Aβ38 generation. Thus, some mutant γ-secretase exhibit a selective to the Aβ42-lowering activity of sulindac sulfide but to the effect robust to sulindac sulfide, the by the cells not Aβ38 and Aβ42 production was further by treatment of cells with is a drug that to exhibit opposite effects modulation by increasing Aβ42 and Aβ38 as with NSAIDs sulindac sulfide and (11Kukar T. Murphy M.P. Eriksen J.L. Sagi S.A. Weggen S. Smith T.E. Ladd T. Khan M.A. Kache R. Beard J. Dodson M. Merit S. Ozols V.V. Anastasiadis P.Z. Das P. Fauq A. Koo E.H. Golde T.E. Nat. Med. 2005; 11: 545-550Crossref PubMed Scopus (260) Google Scholar). all PS1 mutations were to the activity of fenofibrate with WT PS1 Moreover, the mutations such as PS1 and showed only a increase of Aβ42 However, some of the mutations to a with to the activity, they showed robust decreases of Aβ38 PS1 and showed a but reduction of Aβ38 Thus, some PS1 mutations the γ-secretase complex in a that it or to Aβ42 this independently of the The effects on γ-secretase modulation are not to PS1 mutations and the of sulindac sulfide. We a novel with a for γ-secretase modulation of cells expressing WT PS1 with as as of this compound caused a increase in Aβ38 and a decrease in Aβ42 with sulindac sulfide cells expressing showed no in Aβ42 levels a highly robust and increase in Aβ38 this effect was for we investigated cells expressing WT PS2 and PS2 the mutation of cells expressing WT PS2 with caused a increase in Aβ38 and a decrease in Aβ42 not much in Aβ42 was for PS2 N141I a increase in Aβ38 WT cells showed a much increase of Aβ38 with cells expressing WT PS1 and that γ-secretase modulators differentially affect Aβ42 and Aβ38 production in we the effect of the in vivo active modulator in transgenic mice expressing or N141I The modulator reduced Aβ42 levels in the mice together with a increase of Aβ38 levels in a effect on be in the transgenic N141I did not induce reduction of However, it to a increase of Aβ38. the of a reduction of of also be in the transgenic the effect of the γ-secretase in these two transgenic is different for the mutant and Aβ42 is reduced to the and in the transgenic there is a in the N141I transgenic and for and Aβ42, is with a in mice transgenic for the PS1 mutation E. S. C. A. M. Koo E.H. Pietrzik C.U. K. Weggen S. J. Biol. Chem. 2007; Full Text Full Text PDF PubMed Scopus Google Scholar), suggesting that reduced sensitivity to γ-secretase inhibitors in to Aβ42 production may be strong FAD-associated PS the modulator not the amount of Aβ is reduced by the in the transgenic and by in the transgenic Since the of the activity of it was that Aβ42 and Aβ38 generation are as Aβ42 production with Aβ38 generation (10Weggen S. Eriksen J.L. Das P. Sagi S.A. Wang R. Pietrzik C.U. Findlay K.A. Smith T.E. Murphy M.P. Bulter T. Kang D.E. Marquez-Sterling N. Golde T.E. Koo E.H. Nature. 2001; 414: 212-216Crossref PubMed Scopus (1346) Google Scholar, T. Murphy M.P. Eriksen J.L. Sagi S.A. Weggen S. Smith T.E. Ladd T. Khan M.A. Kache R. Beard J. Dodson M. Merit S. Ozols V.V. Anastasiadis P.Z. Das P. Fauq A. Koo E.H. Golde T.E. Nat. Med. 2005; 11: 545-550Crossref PubMed Scopus (260) Google Scholar). Our findings now that Aβ38 generation is not to Aβ42 production. is by the of a negative correlation of Aβ38 levels with Aβ42 levels in the 10 different PS1 mutations Moreover, some FAD-associated PS mutations the γ-secretase complex to the Aβ42-lowering activity of NSAIDs or the activity of fenofibrate, while they are to the to be no correlation the of the mutation and the to Aβ38 the that a selective modulation of these cleavages are not However, using that NSAIDs affect the conformation of PS probably as a the (15Lleo A. Berezovska O. Herl L. Raju S. Deng A. Bacskai B.J. Frosch M.P. Irizarry M. Hyman B.T. Nat. Med. 2004; 10: 1065-1066Crossref PubMed Scopus (205) Google Scholar). Moreover, FAD-associated PS mutations also affect the of the active site by the of the PS1 and in a the effect of Aβ42-lowering NSAIDs (15Lleo A. Berezovska O. Herl L. Raju S. Deng A. Bacskai B.J. Frosch M.P. Irizarry M. Hyman B.T. Nat. Med. 2004; 10: 1065-1066Crossref PubMed Scopus (205) Google Scholar, O. A. Herl Frosch M.P. Bacskai B.J. Hyman B.T. J. Neurosci. 2005; PubMed Scopus Google Scholar). NSAIDs modulate γ-secretase activity in cell-free assays (7Beher D. Clarke E.E. Wrigley J.D. Martin A.C. Nadin A. Churcher I. Shearman M.S. J. Biol. Chem. 2004; 279: 43419-43426Abstract Full Text Full Text PDF PubMed Scopus (191) Google Scholar, 8Eriksen J.L. Sagi S.A. Smith T.E. Weggen S. Das P. McLendon D.C. Ozols V.V. Jessing K.W. Zavitz K.H. Koo E.H. Golde T.E. J. Clin. Investig. 2003; 112: 440-449Crossref PubMed Scopus (0) Google Scholar, 12Takahashi Y. Hayashi I. Tominari Y. Rikimaru K. Morohashi Y. Kan T. Natsugari H. Fukuyama T. Tomita T. Iwatsubo T. J. Biol. Chem. 2003; 278: 18664-18670Abstract Full Text Full Text PDF PubMed Scopus (197) Google Scholar, 13Weggen S. Eriksen J.L. Sagi S.A. Pietrzik C.U. Ozols V. Fauq A. Golde T.E. Koo E.H. J. Biol. Chem. 2003; 278: 31831-31837Abstract Full Text Full Text PDF PubMed Scopus (281) Google Scholar, 14Fraering P.C. Ye W. Strub J.M. Dolios G. LaVoie M.J. Ostaszewski B.L. van Dorsselaer A. Wang R. Selkoe D.J. Wolfe M.S. Biochemistry. 2004; 43: 9774-9789Crossref PubMed Scopus (205) Google Scholar). this that NSAIDs or affect PS conformation and γ-secretase However, that NSAIDs may affect of APP and γ-secretase processing its P. A. D. C. R. M. D. G. EMBO J. 2007; PubMed Scopus Google Scholar). Our the that NSAIDs affect PS activity or by NSAIDs may affect cleavage selective which is well known for FAD-associated PS mutations. mutant PS a certain which in the case of the mutations production of levels of Aβ42, this may not be by NSAIDs or these further and of the of the Aβ may be the activity of NSAIDs may affect within the active site by its Our have strong implications for animal models for in vivo of only transgenic mice with a FAD-associated APP mutation have and in these NSAIDs show their expected activity J.L. Sagi S.A. Smith T.E. Weggen S. Das P. McLendon D.C. Ozols V.V. Jessing K.W. Zavitz K.H. Koo E.H. Golde T.E. J. Clin. Investig. 2003; 112: 440-449Crossref PubMed Scopus (0) Google Scholar, T. Murphy M.P. Eriksen J.L. Sagi S.A. Weggen S. Smith T.E. Ladd T. Khan M.A. Kache R. Beard J. Dodson M. Merit S. Ozols V.V. Anastasiadis P.Z. Das P. Fauq A. Koo E.H. Golde T.E. Nat. Med. 2005; 11: 545-550Crossref PubMed Scopus (260) Google Scholar, J. H. S. R. M. G. J. Neurosci. 2003; 23: PubMed Google Scholar). However, transgenic mice APP in with or PS mutations to and amyloid Our from the PS2 N141I mouse are in with from the PS1 mouse E. S. C. A. M. Koo E.H. Pietrzik C.U. K. Weggen S. J. Biol. Chem. 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). models to a of the in vivo activity of NSAIDs and drugs, because the activity of such drugs may be Moreover, findings also that patients PS1 or PS2 FAD mutations not respond to