Tohru Hasegawa

Urinary Homocysteic Acid Levels Correlate with Mini-Mental State Examination Scores in Alzheimer's Disease Patients

Homocysteic acid (HA) has been suggested as a pathogen in a mouse model of Alzheimers disease (AD), 3xTg-AD. However, it is not established whether HA is involved in humans. We investigated the relationship between urinary HA levels and Mini-Mental State Examination (MMSE) scores in AD patients (n = 70) and non-AD controls (n = 34). We found a positive, statistically significant relationship between the two variables (the urinary HA level and MMSE score) (r = 0.31, p = 0.0008, n = 70). This relationship was stronger in females than males (r = 0.43, p = 0.005, n = 44 in females; r = 0.48, p = 0.02, n = 22 in males). The urinary HA levels were significantly different in AD patients than controls (AD: 8.7 ± 7.5, n = 70; non-dementia control: 13.3 ± 9.4, n = 34, p < 0.01). In addition, aging and smoking were found as lowering factors for urinary HA levels. Our preliminary study showed a negative, statistically significant relationship between blood HA (micromole) and urine HA levels (r = -0.6, p = 0.007, n = 19), and between blood HA levels and MMSE scores (r = -0.79, p = 0.0000518, n = 19). On the basis of these results, we speculate that reduced urinary excretion induces elevated HA levels in blood, resulting in cognitive dysfunctions. This study also suggests that HA may be a candidate of neurotoxins for uremic encephalopathy. Since amyloid-β increases HA toxicity and HA is an agonist of N-methyl-D-aspartic acid (NMDA) receptor, we speculate that elevated blood HA affects the brain cognitive function through NMDA receptor-mediated toxicity in AD.

Protective effect of Japanese green tea against cognitive impairment in the elderly, a two-years follow-up observation

target selective, glial neuroinflammatory responses that are linked to hippocampal neuronal dysfunction, neuronal loss, and spatial learning deficits [2,3,4], and provided a proof of concept that targeting the neuroinflammatory cycle could attenuate disease progression related endpoints. Objective: To take these exploratory basic science results toward development of safe and effective, AD-relevant lead compounds with oral bioavailability, by chemical diversification of the privileged pyridazine core fragment. Methods: Compounds were synthesized and taken through our hierarchical biological screening process involving a) cell-based screening for concentration-dependent and selective inhibition of glia inflammation responses, and b) in vivo assays using mouse models of A -induced neuroinflammation, synaptic dysfunction and neuronal death, in order to discover compounds with in vivo anti-neuroinflammatory activity. An oral toxicological screen was also incorporated into the discovery process [4] by using a multi-day, escalating dose standard protocol. Results and Conclusions: We report here a proof of concept that our approach can produce safe and effective compounds that are orally bioavailable in an animal model of AD-related disease progression. These compounds suppress production of neuroinflammatory cytokines and other biomarkers indicative of A -induced neuroinflammation, and protect against neuronal dysfunction in the hippocampus. These first generation experimental therapeutics are amenable to further medicinal chemistry refinement in future drug development. Current research is focused on medicinal chemistry refinement and safety evaluations as a foundation for phase I clinical investigations. [1] J Med Chem 45: 563-566. [2] Neurobiol. Aging 25: 1283-1292. [3] J Mol Neurosci 24: 115-122. [4] Curr Alzheimer’s Res, in press. (Support: ISOA, Alzheimer’s Association, PhRMA, and NIH grants AG13939, AG21184, NS47586; AG00260, NS46942.

OXIDATIVE STRESS INDUCES AMYLOID AND TAU ALZHEIMER’S BIOMARKERS AND THE COGNITIVE DECLINE OF ALZHEIMER’S DISEASE BY PRODUCTION OF HOMOCYSTEIC ACID

immunized with full-length TDP-43. mTDP-O antibodies were further characterized by dot blot, WB and ELISA assay. FTLD, ALS, and control tissue sections were stained with mTDP-O antibodies. The TDP-43 injection mouse model we used is 5 monthold C57/BL6 mice. The mice were bilaterally injected with TDP43, TDP-43 premixed with one mTDP-O antibody, buffer control or IgG control into hippocampus. The spatial learning and memory were determined by Morris Water Maze. Results:We have generated a panel of mTDP-O antibodies, and characterized the affinity of these TDP-O antibodies against TDP-43 oligomers and monomers. Using mTDP-O antibodies, we found TDP-43 oligomers are present not only in hippocampi of FTLD-TDP patients, but in the motor cortex and spinal cord of ALS patients. Besides, TDP-43 oligomers are partially colocalized with phosphorylated TDP-43 in hippocampus regions of FTLD-TDP patients. The results of Morris Water Maze test in the TDP-43 oligomer injection mouse model showed that TDP-43 oligomer injected mice was deficient in long-term memory. In contrast, the mice injected with TDP-43 oligomer premixed with the mTDP-O antibody behaved normally. The results indicated that the mTDP-O antibody can neutralize the toxicity effect of TDP-43 oligomers. Besides, since TDP-43 pathology presents in up to 57% of AD, now we are using mTDP-O antibodies to evaluate the prevalence of TDP-43 oligomers in AD tissues. Conclustions:TDP-43 oligomers exist in FTLD and ALS patients. Now we are studying whether TDP oligomers are present in AD brain tissues. Moreover, one mTDP-O antibody can neutralize TDP-43 oligomers induced toxicity. TDP-43 oligomer is a potential therapeutic target for TDP-43 pathology related diseases.

THE DISSOCIATION BETWEEN THE COGNITIVE RESERVE ABILITY AND ALZHEIMER'S PATHOLOGY

and is validating novel models (alongside existing models including 5XFAD, APP/PS1 and hTau) using human-relevant biomarkers, imaging methods, neuropathology and functional assays. Future models to be created will be prioritized by a Steering Committee and External Advisory Board with input from the scientific community encouraged. The Preclinical Testing Core has developed a scheme to optimally match test compounds to these new models and to evaluate test compounds through a tiered screening strategy that encompasses pharmacokinetics, target engagement, and functional outcome measures. Results: APOE4 and Trem2 alleles are the strongest known genetic risk factors for LOAD, so we have created a novel model expressing both human APOE4 and the R47H allele of Trem2. This is being phenotypically characterized, and will serve as the standard background as we introduce additional LOAD genetic variants, including ABCA7, IL1RAP and CR1. Conclusions: The MODEL-AD program is generating and making available novel models of LOAD, along with related datasets. We aim to make up to 40 newmodels in the first five years. All newmodels will be made available for both academic and for-profit use from JAX, and all data will be shared via the SAGE-Synapse web portal. We seek input and collaborations from the basic research and pharma/biotech communities.

Targeting therapy for homocysteic acid in the blood represents a potential recovery treatment for cognition in Alzheimer’s disease patients

At present, we have no reliable means of recovering cognitive impairment in Alzheimers disease (AD) patients. We hypothesized that homocysteic acid (HA) in the blood might represent one such pathogen that could be excreted into the urine. Since DHA is known to reduce circulating levels of homocysteine, and since exercise attenuates this effect, it follows that supplementation of the diet with DHA, along with increased levels of physical activity, may help to reduce cognitive impairment in AD patients. Our hypothesis was proven to be correct because memory problems in 3xTg- AD mice (a model for AD in which animals develop amyloid pathology), and in a mouse model of familial AD, were recovered following treatment with an anti-HA antibody and not by amyloid treatment. Interestingly, 3xTg-AD mice with amyloid pathology showed increased levels of HA level. This could perhaps be explained by the fact that amyloid precursor protein and/or presenilin increases calcium influx, which could then increase levels of superoxide and consequently increase levels of HA from homocysteine or methionine. Our hypothesis is also partially supported by an open clinical trial of certain dietary supplements that has shown impressive results. Also there are other treatments hypothesis which would be possible for the effective therapies, such as ribonucleoprotein therapy, a β-secretase inhibitor treatment and the metabolic enhancement treatment.

COGNITIVE RECOVERY BY HBF BRAIN FOOD

Background:Alzheimer Disease (AD) is associated with synapse loss. The medical food Souvenaid 1 contains Fortasyn 1 Connect, a combination of nutrients designed to enhance synapse formation and function in AD. Two earlier studies demonstrated memory improvement in mild AD dementia patients after Souvenaid intervention for 12 and 24 weeks.The 24-week study also showed effects on brain network organisation measured with electroencephalography (EEG), which strengthens the hypothesis that Souvenaid affects synaptic formation and function. To provide further insight into Souvenaid’s hypothesised mode of action, the current NL-ENIGMA study 2 explores brain glucose metabolism in mild cognitive impairment (MCI) and mild dementia due to AD, using Positron Emission Tomography with 18 F-fluorodeoxyglucose (18 F-FDG-PET) as indicator for synapse function. The rationale and study design of the study will be presented. 1 Souvenaid and Fortasyn are registered trademarks of N.V. Nutricia.2 Funded by NWO NIHC project, N 057-13-003. Methods: The NLENIGMA study is an exploratory, randomised controlled study. A total of 40 drug-na€ıve subjects with MCI or mild dementia due to AD (MMSE 20 and presence of amyloid burden) will be 1:1 randomised to receive either Souvenaid (containing Fortasyn Connect) or an iso-caloric control product (without Fortasyn Connect) for a 24-week period. At baseline and after 24 weeks, participants will undergo quantitative 18 F-FDG-PET imaging including arterial sampling. To collect further information on the mode of action of Souvenaid, additional assessments include relative and absolute 18 F-FDG-PET imaging, magnetic resonance imaging (MRI) (i.e. structural MRI, resting-state functional MRI, diffusion tensor imaging and arterial spin labelling), cerebrospinal fluid (CSF) and the assessment of blood parameters. Results: The study will start in May 2014. Conclusions: The NL-ENIGMA study will explore the effect of Souvenaid on brain glucose metabolism in early AD using 18 F-FDG-PET imaging.

O4-04-05: Accelaration of familial Alzheimer's disease by homocysteic acid and recovery from neuropathology by anti-homocysteic acid antibody

received the first 3 injections every 2 weeks and then at monthly intervals. At 7-8 months, the mice went through extensive behavioral testing to determine treatment efficacy and were then killed at 8-9 months for analysis. Results: The immunogen elicited an IgM/IgG response and the therapy prevented cognitive decline in three different tests: Radial Arm Maze (p 0.01-0.001); Closed Field Symmetrical Maze (p 0.01-0.001), and; Object Recognition Test (p 0.01). The groups performed equally well in motor tests indicating that motor deficits were not a confounding variable, which further strengthens our results. Tau/tangle aggregates were reduced by 56% in the pyriform cortex (p 0.01) in the immunized mice. Analysis is underway of other brain regions as well as of levels of soluble and insoluble tau protein. Importantly, the cognitive improvements correlated well with reduction of tau aggregates. In the Radial Arm Maze, correlation was observed in days 4-9 as the mice improve at navigating the maze (p 0.05-0.001). Likewise, in the Closed Field Symmetrical Maze, correlation was only observed in the most complex maze (Maze C, p 0.01), and not in the Object Recognition Test, which is a simpler task. Conclusions: Overall, our findings support the feasibility of immunotherapy targeting pathological tau as a potential treatment for Alzheimer’s disease. Supported by: AG20197.