- Email: [email protected]
Protective effect of Lycoris chejuensis on Alzheimer's disease experimental models in vitro and in vivo
P506
Poster Presentations: P2
APP-transgenic mice from the age of 4 months were fed custom-mix diets (pellets) containing 4% figs. These experimental and control mice were examined at the age of 4-5 months and 10-11 months by Morris water maze test (for spatial memory & learning ability), T maze test (for position discrimination learning ability), rota rod test (for psychomotor coordination), elevated plus maze test (for anxiety-related behavior) and open field test to analyze the effect of diet rich in figs on memory, anxiety and learning skills. Results: APPsw/Tg2576 at the age of 4-5 months and 10-11 months that were fed control diet without figs showed memory deficit, anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability and motor coordination compared to the wild type mice on the same diet. Diets rich in 4% figs when fed to tg mice showed a significant improvement above factors compared to the AD tg mice on diet without figs. Conclusions: Our results suggest that dietary supplementation of figs may have the beneficial effect in reducing the risk, delaying the onset or slowing the progression of Alzheimer’s disease and also our results suggest that further studies needed to validate and determine the mechanism of action of these fruits against AD. P2-404
CLEARANCE OF BETA-AMYLOID PROTOFIBRILS/OLIGOMERS IN THE BRAIN AND CSF OF TG-APP ARCSWE MICE FOLLOWING TREATMENT WITH THE PROTOFIBRILSELECTIVE ANTIBODY MAB158
oderberg1, Karin Tegerstedt1, Anna Lord1, Stina Tucker1, Linda S€ 1 oller1, P€ar Gellerfors1, Andrew Satlin2, Erika Spens , Christer M€ Lars Lannfelt3, 1BioArctic Neuroscience, Stockholm, Sweden; 2Eisai Inc., Woodcliff Lake, New Jersey, United States; 3Uppsala University, Uppsala, Sweden. Contact e-mail: [email protected] Background: Soluble amyloid b (Ab) protofibrils are suggested to play a central role in the pathogenesis of Alzheimer’s disease. Ab monomers gradually aggregate and form larger soluble molecular species (protofibrils/oligomers), which eventually build the insoluble fibrils that deposit in plaques. The soluble forms of Ab correlate better with disease severity than insoluble fibrils. The tgAPP ArcSwe mouse model expresses elevated levels of Ab protofibrils in the brain, and is therefore a suitable model for investigating these Ab species in vivo. Methods: The protofibril-selective monoclonal antibody mAb158 (IgG2a) was given by weekly intraperitoneal injections to aged tg-APP ArcSwe mice, and clearance of soluble brain protofibrils was evaluated in brain TBS extract using a mAb158-based sandwich ELISA, as well as in the CSF using a 82E1-based sandwich ELISA. The mAb158-based sandwich ELISA specifically detects Ab protofibrils, while the 82E1-based sandwich ELISA also detects smaller Ab oligomers, without interference from Ab monomers or treatment antibody present in brain TBS extracts and CSF. Results: Long-term treatment (3 months) of 11-13 months old tg-APP ArcSwe mice with mAb158 (10 mg/kg) led to reduced levels of soluble Ab protofibrils in brain (41%) compared to placebo-treated mice. This reduction was accompanied by a concomitant 53% reduction in oligomeric Ab species in CSF, and a highly significant correlation between brain and CSF Ab protofibril/oligomer levels was observed (R 2 ¼0.297, p<0.0001). Treatment antibody was present in the brain and CSF at 0.2% and 0.05% of the mAb158 concentration measured in plasma, indicating that the treatment antibody reached its target organ. The presence of treatment antibody in the brain suggests that one possible clearance mechanism for soluble Ab protofibrils is via microglial phagocytosis mediated by Fcg-receptors. Conclusions: Treatment with mAb158 cleared toxic Ab protofibrils from brain and this clearance was reflected in CSF, suggesting that oligomeric species of Ab can function as a potential clinical biomarker to monitor treatment effect in Alzheimer’s disease.
P2-405
PROTECTIVE EFFECT OF LYCORIS CHEJUENSIS ON ALZHEIMER’S DISEASE EXPERIMENTAL MODELS IN VITRO AND IN VIVO
Joonki Kim1, Yoon Sun Chun2, Sungkwon Chung3, Hyun Ok Yang4, 1 Korea Institute of Science & Technology, Gangneung, South Korea;
2
Sungkyunkwan University, Suwon, South Korea; 3Sungkyunkwan University School of Medicine, Suwon, South Korea; 4Korea Institute of Science and Technology, Gangneung, South Korea. Contact e-mail: [email protected] Background: Neurotoxic b -amyloid (A b) peptides may play a central role in Alzheimer’s disease (AD). A b is produced by the proteolysis of amyloid b precursor protein (APP). We examined the effect of Lycoris chejuensis (CJ) extract on A b and memory impairment in AD experimental models in vitro and in vivo. The 50% ethanol extract of CJ was selected for use in the experiments. Methods: HeLa cells stably expressing Swedish mutant form of APP (APPswe) were used to test the effect of CJ extract in vitro. After incubating cells with CJ extract for 8 h,A b40 and A b42 levels from the conditioned media were measured using ELISA methods. Double transgenic (TG) mice expressing both APPswe and presenilin-1 mutant were used to test the effect of CJ extract in vivo. Mice were treated orally with CJ extract (50 and 150 mg/kg) for 4 months, and put into Morris water maze and novel object recognition test. After these behavioral tests, cerebral cortex were dissected for plaque detection or for measuring the Ab42 level. Results: In HeLa cells, CJ extract reduced A b40 and A b42 levels in dose-dependent manner, decreasing A b levels by over 90% at 50 mg/ml concentration. CJ extract decreased the levels of immature APP as well as mature APP. Compared with immature form of APP, mature form of APP was much more potently decreased. Taken together, CJ extract may reduce A b by attenuating APP levels.CJ extract significantly enhanced spatial memory in TG mice, improving both acquisition and probe phases in Morris water maze test. CJ extract also increased the exploration time in novel object recognition test. Toxic Ab42 level as well as amyloid plaques were significantly decreased in animals treated with CJ extract. Conclusions: Our data suggest that CJ extract reduces toxic A b42 levels in the brain, and ameliorates the memory impairment in AD animal model. Lycoris genus plant, such as Lycoris radiata, has been used to develop anti-AD agent such as galantamine. Thus, further research on the constituents of CJ extract and the mechanism of action will be needed for the treatment of AD.
P2-406
THE THERAPEUTIC EFFECTS OF ICARRIN ON BETA-AMYLOID BURDEN IN A MOUSE MODEL OF ALZHEIMER’S DISEASE
Lan Zhang1, Cong Shen2, Lin Li3, 1Xuan-Wu Hospital of Capital Medical University, Beijing, China; 2Xuanwu Hospital of Capital Medical University, Beijing, China; 3Department of Pharmacology, Xuanwu Hospital of Capital Medical University, Beijing, China. Contact e-mail: [email protected] Background: To investigate the effect and pharmacological mechanism of Icarrin (ICA), which is the main component extracted from a traditional Chinese Epimedium herb, on Ab production in AD-like APP transgenic mice. Methods: PDAPPV717I transgenic (Tg) mice were randomly divided into model group and ICA treated (at doses 30 and 100 mmol/kg/d) groups. ICA was orally administered to Tg mice with an age range 4-10 months. The burden of Ab was measured by ELISA and immunohistochemistry. The amyloid senile plaques were detected by Congo red staining and Bielschowsky silver staining. The expression of APP and BACE-1 were measured by immunohistochemistry and Western blot. The co-expression of Ab with amyloid fibers was detected by applying double labeled immunofluorescence. Results: Orally administered ICA decreased the number of amyloid senile plaques in hippocampus of Tg mice. The immunohistochemical examination of brain sections stained with polyclonal anti-Ab antibody showed reduced Ab burden, and Ab levels were also decreased in the insoluble fractions of brain homogenates, as determined by ELISA. The expression of APP and BACE-1 in hippocampus was significantly decreased in ICA treated groups. Conclusions: ICA could reduce the Ab burden and plaque deposits in the hippocampus of APP transgenic mice through depressing the expression of APP and BACE-1. Icarrin may have a promising application prospect in treatment of AD.
Poster Presentations: P2
APP-transgenic mice from the age of 4 months were fed custom-mix diets (pellets) containing 4% figs. These experimental and control mice were examined at the age of 4-5 months and 10-11 months by Morris water maze test (for spatial memory & learning ability), T maze test (for position discrimination learning ability), rota rod test (for psychomotor coordination), elevated plus maze test (for anxiety-related behavior) and open field test to analyze the effect of diet rich in figs on memory, anxiety and learning skills. Results: APPsw/Tg2576 at the age of 4-5 months and 10-11 months that were fed control diet without figs showed memory deficit, anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability and motor coordination compared to the wild type mice on the same diet. Diets rich in 4% figs when fed to tg mice showed a significant improvement above factors compared to the AD tg mice on diet without figs. Conclusions: Our results suggest that dietary supplementation of figs may have the beneficial effect in reducing the risk, delaying the onset or slowing the progression of Alzheimer’s disease and also our results suggest that further studies needed to validate and determine the mechanism of action of these fruits against AD. P2-404
CLEARANCE OF BETA-AMYLOID PROTOFIBRILS/OLIGOMERS IN THE BRAIN AND CSF OF TG-APP ARCSWE MICE FOLLOWING TREATMENT WITH THE PROTOFIBRILSELECTIVE ANTIBODY MAB158
oderberg1, Karin Tegerstedt1, Anna Lord1, Stina Tucker1, Linda S€ 1 oller1, P€ar Gellerfors1, Andrew Satlin2, Erika Spens , Christer M€ Lars Lannfelt3, 1BioArctic Neuroscience, Stockholm, Sweden; 2Eisai Inc., Woodcliff Lake, New Jersey, United States; 3Uppsala University, Uppsala, Sweden. Contact e-mail: [email protected] Background: Soluble amyloid b (Ab) protofibrils are suggested to play a central role in the pathogenesis of Alzheimer’s disease. Ab monomers gradually aggregate and form larger soluble molecular species (protofibrils/oligomers), which eventually build the insoluble fibrils that deposit in plaques. The soluble forms of Ab correlate better with disease severity than insoluble fibrils. The tgAPP ArcSwe mouse model expresses elevated levels of Ab protofibrils in the brain, and is therefore a suitable model for investigating these Ab species in vivo. Methods: The protofibril-selective monoclonal antibody mAb158 (IgG2a) was given by weekly intraperitoneal injections to aged tg-APP ArcSwe mice, and clearance of soluble brain protofibrils was evaluated in brain TBS extract using a mAb158-based sandwich ELISA, as well as in the CSF using a 82E1-based sandwich ELISA. The mAb158-based sandwich ELISA specifically detects Ab protofibrils, while the 82E1-based sandwich ELISA also detects smaller Ab oligomers, without interference from Ab monomers or treatment antibody present in brain TBS extracts and CSF. Results: Long-term treatment (3 months) of 11-13 months old tg-APP ArcSwe mice with mAb158 (10 mg/kg) led to reduced levels of soluble Ab protofibrils in brain (41%) compared to placebo-treated mice. This reduction was accompanied by a concomitant 53% reduction in oligomeric Ab species in CSF, and a highly significant correlation between brain and CSF Ab protofibril/oligomer levels was observed (R 2 ¼0.297, p<0.0001). Treatment antibody was present in the brain and CSF at 0.2% and 0.05% of the mAb158 concentration measured in plasma, indicating that the treatment antibody reached its target organ. The presence of treatment antibody in the brain suggests that one possible clearance mechanism for soluble Ab protofibrils is via microglial phagocytosis mediated by Fcg-receptors. Conclusions: Treatment with mAb158 cleared toxic Ab protofibrils from brain and this clearance was reflected in CSF, suggesting that oligomeric species of Ab can function as a potential clinical biomarker to monitor treatment effect in Alzheimer’s disease.
P2-405
PROTECTIVE EFFECT OF LYCORIS CHEJUENSIS ON ALZHEIMER’S DISEASE EXPERIMENTAL MODELS IN VITRO AND IN VIVO
Joonki Kim1, Yoon Sun Chun2, Sungkwon Chung3, Hyun Ok Yang4, 1 Korea Institute of Science & Technology, Gangneung, South Korea;
2
Sungkyunkwan University, Suwon, South Korea; 3Sungkyunkwan University School of Medicine, Suwon, South Korea; 4Korea Institute of Science and Technology, Gangneung, South Korea. Contact e-mail: [email protected] Background: Neurotoxic b -amyloid (A b) peptides may play a central role in Alzheimer’s disease (AD). A b is produced by the proteolysis of amyloid b precursor protein (APP). We examined the effect of Lycoris chejuensis (CJ) extract on A b and memory impairment in AD experimental models in vitro and in vivo. The 50% ethanol extract of CJ was selected for use in the experiments. Methods: HeLa cells stably expressing Swedish mutant form of APP (APPswe) were used to test the effect of CJ extract in vitro. After incubating cells with CJ extract for 8 h,A b40 and A b42 levels from the conditioned media were measured using ELISA methods. Double transgenic (TG) mice expressing both APPswe and presenilin-1 mutant were used to test the effect of CJ extract in vivo. Mice were treated orally with CJ extract (50 and 150 mg/kg) for 4 months, and put into Morris water maze and novel object recognition test. After these behavioral tests, cerebral cortex were dissected for plaque detection or for measuring the Ab42 level. Results: In HeLa cells, CJ extract reduced A b40 and A b42 levels in dose-dependent manner, decreasing A b levels by over 90% at 50 mg/ml concentration. CJ extract decreased the levels of immature APP as well as mature APP. Compared with immature form of APP, mature form of APP was much more potently decreased. Taken together, CJ extract may reduce A b by attenuating APP levels.CJ extract significantly enhanced spatial memory in TG mice, improving both acquisition and probe phases in Morris water maze test. CJ extract also increased the exploration time in novel object recognition test. Toxic Ab42 level as well as amyloid plaques were significantly decreased in animals treated with CJ extract. Conclusions: Our data suggest that CJ extract reduces toxic A b42 levels in the brain, and ameliorates the memory impairment in AD animal model. Lycoris genus plant, such as Lycoris radiata, has been used to develop anti-AD agent such as galantamine. Thus, further research on the constituents of CJ extract and the mechanism of action will be needed for the treatment of AD.
P2-406
THE THERAPEUTIC EFFECTS OF ICARRIN ON BETA-AMYLOID BURDEN IN A MOUSE MODEL OF ALZHEIMER’S DISEASE
Lan Zhang1, Cong Shen2, Lin Li3, 1Xuan-Wu Hospital of Capital Medical University, Beijing, China; 2Xuanwu Hospital of Capital Medical University, Beijing, China; 3Department of Pharmacology, Xuanwu Hospital of Capital Medical University, Beijing, China. Contact e-mail: [email protected] Background: To investigate the effect and pharmacological mechanism of Icarrin (ICA), which is the main component extracted from a traditional Chinese Epimedium herb, on Ab production in AD-like APP transgenic mice. Methods: PDAPPV717I transgenic (Tg) mice were randomly divided into model group and ICA treated (at doses 30 and 100 mmol/kg/d) groups. ICA was orally administered to Tg mice with an age range 4-10 months. The burden of Ab was measured by ELISA and immunohistochemistry. The amyloid senile plaques were detected by Congo red staining and Bielschowsky silver staining. The expression of APP and BACE-1 were measured by immunohistochemistry and Western blot. The co-expression of Ab with amyloid fibers was detected by applying double labeled immunofluorescence. Results: Orally administered ICA decreased the number of amyloid senile plaques in hippocampus of Tg mice. The immunohistochemical examination of brain sections stained with polyclonal anti-Ab antibody showed reduced Ab burden, and Ab levels were also decreased in the insoluble fractions of brain homogenates, as determined by ELISA. The expression of APP and BACE-1 in hippocampus was significantly decreased in ICA treated groups. Conclusions: ICA could reduce the Ab burden and plaque deposits in the hippocampus of APP transgenic mice through depressing the expression of APP and BACE-1. Icarrin may have a promising application prospect in treatment of AD.