1
Poster Session P4: Therapeutics and Therapeutic Strategies - Therapeutic Strategies, Amyloid-Based $587 ~ CEREBROLYSIN TM PROTECTS AGAINST CEREBROVASCULAR AMYLOID ANGIOPATHY IN A TRANSGENIC MODEL OF ALZHEIMER'S DISEASE Edward Rockenstein* 1, Anthony Adame 1, Michael Mante 1, Herber Moessler 2, Mantled Windisch 3 , Eliezer Masliah 1. 1 University of California San Diego, La Jolla, CA, USA; 2 EBEWE Pharmaceuticals, Unterach, Austria; 3 JSW Research, Graz, Austria. Contact e-mail: erockenstein @ ucsd. edu Background: Increased production and reduced clearance of amyloid (A[~) plays a central role in the pathogenesis of Alzheimer's disease (AD). We have recently shown that the neurotrophic peptide mixture- Cerebrolysin TM (Cbl) has the ability of improving synaptic functioning and reducing amyloid deposition in a transgenic animal model of Alzheimer's disease (AD). Objective(s): Since in AD, potentially toxic A[~ aggregates not only accumulate around neurons but also in the blood vessels, then it is important to investigate if bioactive compounds such as Cbl might have the capacity of ameliorating the age related cerebrovascular amyloid angiopathy (CAA) in tg models. Methods: Tg mice expressing mutant human amyloid precursor protein (APP) under the Thyl promoter were treated with Cbl or vehicle alone starting at 7 or 12 months of age for a total of three months. Results: Neuropathological analysis with an antibody against A[3 showed that Cbl decreased amyloid deposition around the blood vessels in a time dependant manner. These effects were accompanied by a reduction in peri-vascular astrogliosis and increased expression of markers of vascular fitness such as CD31, occluding and Glut-1. Consistent with these findings, ultrastructural analysis showed that while in tg mice treated with vehicle alone there was abundant accumulation of amyloid fibers in the vascular wall accompanied by thickening of the basal membrane and endothelial cell damage, in Cbl treated mice there was considerable reduction in the subcellular alterations of endothelial and smooth muscle ceils with preservation of basal membranes and intercellular junctions. Conclusions: Taken together, these results suggest that Cerebrolysin treatment might have 5eneficial effects in patients with cognitive impairment by reducing A~ accumulation and promoting the preservation of synaptic terminals ADMINISTRATION OF AN ANTI-AI3 FAB FRAGMENT TO APP V717F TRANSGENIC MICE REDUCES NEURITIC PLAQUE K.R. Bales *l , J. Dorocke 2, D. Koger I , C. DeLong ~ , S. Wu t , M. Raeke 1, U. Kuchibhotla 3 , V. Wroblewski 1, R. DeMattos 1, J. Lu 2. 1Neuroscience Discovery Research, Indianapolis, IN, USA; 2 Biotherapeutic Discovery Research, Indianapolis, IN, USA; 3 Biotherapeutic Discovery Research, Indianapolis, IN, USA. Contact e-mail: [email protected] Background: Previously we reported that chronic administration of the anti-A[3 antibody m266 was able to prevent brain A[~ aeeural in APP v717F transgenic mice (tg mice). We hypothesized that m266 administration was able to prevent plaque accrual by creating a "peripheral sink" thus allowing for the movement of centrally derived A[3 to the periphery where it is efficiently degraded. Objectives: Since the pharmacokinetic properties of Fab fragments differ with respect to a decreased half-life when compared to an intact IgG molecule, we wanted to investigate whether administration of m266 Fab would be more or less efficacious at lowering brain A[3 burden. Methods: In order to investigate whether administration of Fab m266 could reverse brain A[~ burden, we administered m266 Fab (100 l~,g/mouse), m266 (14 t~g/mouse), or PBS (i.p.) daily for 3 months to very old (18 mouths of age) tg mice. A significant reduction in the level of cortical AIM2 as determined by a sensitive sandwich ELISA occurred following either m266 or m266 Fab administration. The levels of plasma A~40 and A[342 were significantly greater when measured 6 and 24 hrs after the last dose of either m266 Fab or 266 when compared to PBS treated tg mice. Accumulation of plasma AIM0 or AIM2 was significantly greater however, when mice were administered m266 compared to m266 Fab. Next we determined the relative level of brain A~ burden as well as neuritic dystrophy by quantitative im- munohistochemistry. In contrast to a significant decrease in both AIM0 and AIM2 as determined by ELISA analysis of brain homogenates, there was no significant difference in the relative level of brain At3 burden between any of the treated groups as determined by quantitative immunohistochemistry. Importantly, however, there was a significant decrease in dystrophic neurites following chronic m266 Fab administration when compared to the PBS treated group. Conclusions: Our results suggest that chronic daily admin- istration of m266 Fab is able to reduce brain A[3 burden, as determined by ELISA, as well as dystrophic neurites despite a relatively short half-life and only a modest (> 15-fold) elevation in plasma A[3 levels. ZWITTERIONIC COMPOUNDS PROMOTE CONFORMATIONALLY AND MORPHOLOGICALLY UNIQUE CHANGES IN THE Aft PEPTIDE Richard W. McLanghlin* 1 Xianqi Kong 1 , Xinfu Wu 1, Dino Stta 1, Louis Lavoie 2'3, Philippe Sarazin 1, Ahmed Aman l , Hojatollah Vali 4, Francine Gervais 2.3, Patrick Tremblay 1. YNeurochem Inc., Ville Saint-Laurent, PQ, Canada; 2Nearochem (International) Limited, Dorval, PQ, Canada; 3Neurochem (International) Limited, Walchwil, Switzerland; 4McGill University, Dept. of Anatomy and Cell Biology, Montreal, PQ, Canada. Contact e-mail: [email protected] Background: The amyloid cascade hypothesis suggests that Alzheimer's disease is caused by structural changes in the amyloid-[~ (A[~) peptide leading to the formation of amyldid fibril deposits and senile plaques. Plaque formation is facilitated by a number of factors such as chaperones, glyeosaminoglycans and metal ions. These factors associate with A[3 and accelerate the formation of insoluble protease-resistant neurotoxic aggre- gates. Objectives: Efforts to develop anti-fibrillogenie agents have led to the characterization of four zwitterionic compounds, two of which promote the formation of morphologically-unique [3-amyloid fibrils: dimethyl(3- sulfopropyl) decylammonium hydroxide (I), dimethyl(3-sulfopropyl) dode- cylammonium hydroxide (II), dimethyl(3-sulfopropyl) tetradecylarnmonium hydroxide (III) and dimethyl(3-sulfopropyl) hexadecylammoninm hydrox- ide (IV). Methods and results: Circular dichroism studies demonstrated that these compounds promote the formation of [~-sheet in a chain length- dependent manner such that compounds III and IV are the most active. Transmission electron microscopy of high-resolution platinum/carbon repli- cas revealed that A[~ fibers assembled in the presence of compounds III and IV exhibit an atypical network of braided and highly branched fibrils. Both mass spectrometry and 1H NMR studies confirmed that these com- pounds bind directly to soluble AlL Preliminary results from 2D-NOESY experiments also indicated that the presence of these compounds induce distinct conformational changes in A[3 peptides. Conclusions: Altogether our findings document unique promoters of amyloid formation able to bind to the A~ peptide, promote unique conformationat transitions and lead to conformationally-distinct A~ fibrils. NEUROPROTECTION BY INDOLE AND NITRONE COMPOUNDS ACTING AS MITOCHONDRIAL METABOLISM MODIFIERS WITH POTENT ANTIOXIDANT ACTIVITY Burkhard Poeggeler*. Institute of Zoology, Anthropology and Developmental Biology, Goettingen, Germany. Contact e-mail: bpoegge @ gwdg.de Background: The high incidence of Alzheimer's disease (AD) in our aging population represents a great challenge to biomedicine. Objective(s): A potential mechanism to slow the disease process and to target its underlying pathology is the use of antioxidants. Methods: Antioxidant protection is measured in neuronal cultures and invertebrate animals such as rotifers. Results: Advanced antioxidant agents can increase mitochondrial energy metabolism efficacy and improve oxygen utilization by reducing radical generation and enhancing ATP formation. Conclusions: Since neuronal damage, degeneration and death induced by anayloid oxidotoxicity is primarily of mitochondrial origin, these new compounds under development should have a great potential for neuroprotection. The promising current

P4-397 Zwitterionic compounds promote conformationally and morphologically unique changes in the Aβ peptide

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Page 1: P4-397 Zwitterionic compounds promote conformationally and morphologically unique changes in the Aβ peptide

Poster Session P4: Therapeutics and Therapeutic Strategies - Therapeutic Strategies, Amyloid-Based $587

~ C E R E B R O L Y S I N T M P R O T E C T S AGAINS T C E R E B R O V A S C U L A R A M Y L O I D A N G I O P A T H Y IN A T R A N S G E N I C M O D E L OF A L Z H E I M E R ' S DISEASE

Edward Rockenstein* 1, Anthony Adame 1, Michael Mante 1, Herber Moessler 2, Mantled Windisch 3 , Eliezer Masliah 1 . 1 University of California San Diego, La Jolla, CA, USA; 2 EBEWE Pharmaceuticals, Unterach, Austria; 3 JSW Research, Graz, Austria. Contact e-mail: erockenstein @ ucsd. edu

Background: Increased production and reduced clearance of amyloid (A[~) plays a central role in the pathogenesis of Alzheimer's disease (AD). We have recently shown that the neurotrophic peptide mixture- Cerebrolysin TM (Cbl) has the ability of improving synaptic functioning and reducing amyloid deposition in a transgenic animal model of Alzheimer's disease (AD). Objective(s): Since in AD, potentially toxic A[~ aggregates not only accumulate around neurons but also in the blood vessels, then it is important to investigate if bioactive compounds such as Cbl might have the capacity of ameliorating the age related cerebrovascular amyloid angiopathy (CAA) in tg models. Methods: Tg mice expressing mutant human amyloid precursor protein (APP) under the Thyl promoter were treated with Cbl or vehicle alone starting at 7 or 12 months of age for a total of three months. Results: Neuropathological analysis with an antibody against A[3 showed that Cbl decreased amyloid deposition around the blood vessels in a time dependant manner. These effects were accompanied by a reduction in peri-vascular astrogliosis and increased expression of markers of vascular fitness such as CD31, occluding and Glut-1. Consistent with these findings, ultrastructural analysis showed that while in tg mice treated with vehicle alone there was abundant accumulation of amyloid fibers in the vascular wall accompanied by thickening of the basal membrane and endothelial cell damage, in Cbl treated mice there was considerable reduction in the subcellular alterations of endothelial and smooth muscle ceils with preservation of basal membranes and intercellular junctions. Conclusions: Taken together, these results suggest that Cerebrolysin treatment might have 5eneficial effects in patients with cognitive impairment by reducing A~ accumulation and promoting the preservation of synaptic terminals

• ADMINISTRATION OF AN ANTI-AI3 FAB F R A G M E N T T O APP V717F T R A N S G E N I C M I C E REDUCES N E U R I T I C P L A Q U E

K.R. Bales *l , J. Dorocke 2, D. Koger I , C. DeLong ~ , S. Wu t , M. Raeke 1 , U. Kuchibhotla 3 , V. Wroblewski 1 , R. DeMattos 1 , J. Lu 2. 1Neuroscience Discovery Research, Indianapolis, IN, USA; 2 Biotherapeutic Discovery Research, Indianapolis, IN, USA; 3 Biotherapeutic Discovery Research, Indianapolis, IN, USA. Contact e-mail: [email protected]

Background: Previously we reported that chronic administration of the anti-A[3 antibody m266 was able to prevent brain A[~ aeeural in APP v717F transgenic mice (tg mice). We hypothesized that m266 administration was able to prevent plaque accrual by creating a "peripheral sink" thus allowing for the movement of centrally derived A[3 to the periphery where it is efficiently degraded. Objectives: Since the pharmacokinetic properties of Fab fragments differ with respect to a decreased half-life when compared to an intact IgG molecule, we wanted to investigate whether administration of m266 Fab would be more or less efficacious at lowering brain A[3 burden. Methods: In order to investigate whether administration of Fab m266 could reverse brain A[~ burden, we administered m266 Fab (100 l~,g/mouse), m266 (14 t~g/mouse), or PBS (i.p.) daily for 3 months to very old (18 mouths of age) tg mice. A significant reduction in the level of cortical AIM2 as determined by a sensitive sandwich ELISA occurred following either m266 or m266 Fab administration. The levels of plasma A~40 and A[342 were significantly greater when measured 6 and 24 hrs after the last dose of either m266 Fab or 266 when compared to PBS treated tg mice. Accumulation of plasma AIM0 or AIM2 was significantly greater however, when mice were administered m266 compared to m266 Fab. Next we determined the relative level of brain A~ burden as well as neuritic dystrophy by quantitative im- munohistochemistry. In contrast to a significant decrease in both AIM0 and

AIM2 as determined by ELISA analysis of brain homogenates, there was no significant difference in the relative level of brain At3 burden between any of the treated groups as determined by quantitative immunohistochemistry. Importantly, however, there was a significant decrease in dystrophic neurites following chronic m266 Fab administration when compared to the PBS treated group. Conclusions: Our results suggest that chronic daily admin- istration of m266 Fab is able to reduce brain A[3 burden, as determined by ELISA, as well as dystrophic neurites despite a relatively short half-life and only a modest (> 15-fold) elevation in plasma A[3 levels.

• Z W I T T E R I O N I C C O M P O U N D S P R O M O T E C O N F O R M A T I O N A L L Y AND M O R P H O L O G I C A L L Y UNIQUE C H A N G E S IN THE Aft PEPTIDE

Richard W. McLanghlin* 1 Xianqi Kong 1 , Xinfu Wu 1, Dino Stta 1, Louis Lavoie 2'3 , Philippe Sarazin 1 , Ahmed Aman l , Hojatollah Vali 4, Francine Gervais 2.3, Patrick Tremblay 1 . YNeurochem Inc., Ville Saint-Laurent, PQ, Canada; 2Nearochem (International) Limited, Dorval, PQ, Canada; 3Neurochem (International) Limited, Walchwil, Switzerland; 4McGill University, Dept. of Anatomy and Cell Biology, Montreal, PQ, Canada. Contact e-mail: [email protected]

Background: The amyloid cascade hypothesis suggests that Alzheimer's disease is caused by structural changes in the amyloid-[~ (A[~) peptide leading to the formation of amyldid fibril deposits and senile plaques. Plaque formation is facilitated by a number of factors such as chaperones, glyeosaminoglycans and metal ions. These factors associate with A[3 and accelerate the formation of insoluble protease-resistant neurotoxic aggre- gates. Objectives: Efforts to develop anti-fibrillogenie agents have led to the characterization of four zwitterionic compounds, two of which promote the formation of morphologically-unique [3-amyloid fibrils: dimethyl(3- sulfopropyl) decylammonium hydroxide (I), dimethyl(3-sulfopropyl) dode- cylammonium hydroxide (II), dimethyl(3-sulfopropyl) tetradecylarnmonium hydroxide (III) and dimethyl(3-sulfopropyl) hexadecylammoninm hydrox- ide (IV). Methods and results: Circular dichroism studies demonstrated that these compounds promote the formation of [~-sheet in a chain length- dependent manner such that compounds III and IV are the most active. Transmission electron microscopy of high-resolution platinum/carbon repli- cas revealed that A[~ fibers assembled in the presence of compounds III and IV exhibit an atypical network of braided and highly branched fibrils. Both mass spectrometry and 1H NMR studies confirmed that these com- pounds bind directly to soluble AlL Preliminary results from 2D-NOESY experiments also indicated that the presence of these compounds induce distinct conformational changes in A[3 peptides. Conclusions: Altogether our findings document unique promoters of amyloid formation able to bind to the A~ peptide, promote unique conformationat transitions and lead to conformationally-distinct A~ fibrils.

• N E U R O P R O T E C T I O N BY I N D O L E AND N I T R O N E C O M P O U N D S A C T I N G AS M I T O C H O N D R I A L M E T A B O L I S M M O D I F I E R S W I T H P O T E N T ANTIOXIDANT ACTIVITY

Burkhard Poeggeler*. Institute of Zoology, Anthropology and Developmental Biology, Goettingen, Germany. Contact e-mail: bpoegge @ gwdg.de

Background: The high incidence of Alzheimer's disease (AD) in our aging population represents a great challenge to biomedicine. Objective(s): A potential mechanism to slow the disease process and to target its underlying pathology is the use of antioxidants. Methods: Antioxidant protection is measured in neuronal cultures and invertebrate animals such as rotifers. Results: Advanced antioxidant agents can increase mitochondrial energy metabolism efficacy and improve oxygen utilization by reducing radical generation and enhancing ATP formation. Conclusions: Since neuronal damage, degeneration and death induced by anayloid oxidotoxicity is primarily of mitochondrial origin, these new compounds under development should have a great potential for neuroprotection. The promising current