Alzheimer Disease: Wang J

Brinton RD, Thompson RF, Foy MR, Baudry M, Wang J, Finch CE, Morgan TE, Pike CJ, Mack WJ, Stanczyk FZ, Nilsen J. · Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA. · Front Neuroendocrinol. · Pubmed #18374402 links to  free full text

Abstract: Emerging data indicate that progesterone has multiple non-reproductive functions in the central nervous system to regulate cognition, mood, inflammation, mitochondrial function, neurogenesis and regeneration, myelination and recovery from traumatic brain injury. Progesterone-regulated neural responses are mediated by an array of progesterone receptors (PR) that include the classic nuclear PRA and PRB receptors and splice variants of each, the seven transmembrane domain 7TMPRbeta and the membrane-associated 25-Dx PR (PGRMC1). These PRs induce classic regulation of gene expression while also transducing signaling cascades that originate at the cell membrane and ultimately activate transcription factors. Remarkably, PRs are broadly expressed throughout the brain and can be detected in every neural cell type. The distribution of PRs beyond hypothalamic borders, suggests a much broader role of progesterone in regulating neural function. Despite the large body of evidence regarding progesterone regulation of reproductive behaviors and estrogen-inducible responses as well as effects of progesterone metabolite neurosteroids, much remains to be discovered regarding the functional outcomes resulting from activation of the complex array of PRs in brain by gonadally and/or glial derived progesterone. Moreover, the impact of clinically used progestogens and developing selective PR modulators for targeted outcomes in brain is a critical avenue of investigation as the non-reproductive functions of PRs have far-reaching implications for hormone therapy to maintain neurological health and function throughout menopausal aging.

Pasinetti GM, Zhao Z, Qin W, Ho L, Shrishailam Y, Macgrogan D, Ressmann W, Humala N, Liu X, Romero C, Stetka B, Chen L, Ksiezak-Reding H, Wang J. · Neuroinflammation Research Laboratories, Department of Psychiatry, Mount Sinai School of Medicine, 1 Gustave L. Levy Place, New York, NY 10029, USA. · Interdiscip Top Gerontol. · Pubmed #17063038 No free full text.

Abstract: Alzheimer's disease (AD) is a rapidly growing public health concern with potentially devastating effects. Presently, there are no known cures or effective preventive strategies. While genetic factors are relevant in early-onset cases, they appear to play less of a role in late-onset sporadic AD cases, the most common form of AD. Due to the fact that the disease typically strikes very late in life, delaying symptoms could be as good as a cure for many people. For example, it is now widely accepted that if the onset of the disease could be delayed by even 5 years, the incidence could be cut in half. Both clinical and epidemiological evidence suggests that modification of lifestyle factors such as nutrition may prove crucial to AD management given the mounting experimental evidence suggesting that brain cells are remarkably responsive to "what somebody is doing". Among other nongenetic factors influencing AD, recent studies strongly support the evidence that caloric intake may play a role in the relative risk for AD clinical dementia. Indeed, the effect of diet in AD has been an area of research that has produced promising results, at least experimentally. Most importantly, as mechanistic pathways are defined and their biochemical functions scrutinized, the evidence supporting a direct link between nutrition and AD neuropathology continues to grow. Our work, as well as that of others, has recently resulted in the development of experimental dietary regimens that might promote, attenuate or even reverse features of AD. Most remarkably, while we found that high caloric intake based on saturated fat promotes AD type Beta-amyloidosis, conversely we found that dietary restriction based on reduced carbohydrate intake is able to prevent it. This evidence is very exciting and is, in part, consistent with current epidemiological studies suggesting that obesity and diabetes are associated with a >4-fold increased risk of developing AD. The clarification of the mechanisms through which dietary restriction may beneficially influence AD neuropathology and the eventual discovery of future "mimetics" capable of anti-Beta-amyloidogenic activity will help in the development of "lifestyle therapeutic strategies" in AD and possibly other neurodegenerative disorders.

Tian Q, Wang J. · Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China. · Neurosignals. · Pubmed #12566927 No free full text.

Abstract: Accumulating evidence indicates that serine/threonine (Ser/Thr) protein phosphatases (PPs), such as PP1, PP2A and PP2B, participate in the neurodegenerative progress in Alzheimer's disease (AD). The general characteristics and pathologic changes of PP1, PP2A and PP2B in AD, and their relations with microtubule-associated proteins, focusing mainly on tau protein, neurofilament (NF), amyloid precursor protein (APP) processing and synaptic plasticity are discussed. Deriving novel insight into the particular topic will attract greater attention to more active investigation and effective therapeutic intervention in the future.

Jankowsky JL, Savonenko A, Schilling G, Wang J, Xu G, Borchelt DR. · Department of Pathology, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross Building Room 558, Baltimore, MD 21205, USA. · Curr Neurol Neurosci Rep. · Pubmed #12169227 No free full text.

Abstract: Neurodegenerative diseases present an extraordinary challenge for medicine due to the grave nature of these illnesses, their prevalence, and their impact on individuals and caregivers. The most common of these age-associated chronic illnesses are Alzheimer's disease (AD) and Parkinson's disease (PD); other examples include the prion disorders, amyotrophic lateral sclerosis (ALS), and the trinucleotide (CAG) repeat diseases. All of these diseases are characterized by well-defined clinical syndromes with progressive courses that reflect the dysfunction and eventual loss of specific neuronal populations. Current therapies provide only symptomatic relief; none significantly alter the course of disease. We describe here how transgenic mice designed to model these diseases have substantially contributed to the identification and validation of many promising new therapies, and conversely how they have quickly and cost effectively eliminated several targets with unrealized expectations.

Lin SM, Wang J, Zhou RQ. · Institute of Geriatrics, Shanghai TCM University, Shanghai 200038. · Zhongguo Zhong Xi Yi Jie He Za Zhi. · Pubmed #14503055 No free full text.

Abstract: OBJECTIVE: To explore the therapeutic mechanism of Tiaoxin Recipe (TXR) and Bushen Recipe (BSR) in treating Alzheimer's disease (AD). METHODS: Sixty patients with AD were divided into 3 groups according to their MMSE and ADL scores before treatment, using randomized block design. They were treated separately with TXR, BSR and Donepezil (Dp) for 12 weeks. The changes of MMSE score, ADL score, neuro-psychology amount table score, including FOM, RVR, DS and BD, as well as the overall operational evaluation before and after treatment were analyzed. RESULTS: The recognition and daily life capacity of patients in the 3 groups were improved after treatment. MMSE score in the TXR group increased from 16.10 +/- 1.94 scores before treatment to 17.90 +/- 2.59 scores after treatment, in the BSR group, from 16.15 +/- 2.16 to 17.50 +/- 2.59, and in the Dp group, from 17.35 +/- 1.90 to 19.60 +/- 3.39, all showed significant difference (all P < 0.01). Change of ADL score showed that in TXR from 43.10 +/- 3.86 to 41.50 +/- 4.40, in the BSR group from 43.30 +/- 4.53 to 41.60 +/- 4.12 and in the Dp group, from 42.95 +/- 3.58 to 40.60 +/- 5.23, which also showed significant difference (P < 0.05 or P < 0.01). Moreover, increase of FOM, RVR and DS score was shown in the TXR and the Dp group, and increase of RVR and BD score was shown in the BSR group with significant difference in comparison of corresponding score before and after treatment, inter-groups comparison showed significant difference of FOM score between the BSR and the Dp group (P < 0.01). Overall operational evaluation (total effective rate) in the TXR group was 70%, in the BSR group 65% and in Dp group 75%, with no significant difference among them. CONCLUSION: TXR and BSR are effective TCM drugs in treating AD.

Zhang Z, Wang X, Chen Q, Shu L, Wang J, Shan G. · Department of Neurology and Clinical Epidemiology Unit, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. · Zhonghua Yi Xue Za Zhi. · Pubmed #12181083 No free full text.

Abstract: OBJECTIVE: To evaluate the clinical efficacy and safety of huperzine Alpha in treatment of patients with mild to moderate Alzheimer disease (AD). METHODS: Two hundred and two patients with the diagnosis of possible or probable AD from 15 centers the nationwide were randomly divided into two groups: huperzine Alpha group (n = 100, given huperzine Alpha 400 micro g/day for 12 weeks) and placebo group (n = 102 ). Different scales were used to evaluate the cognitive function, activity of daily life (ADL), non-cognitive disorders, and overall clinical efficacy. Safety evaluation was conducted every 6 weeks. RESULTS: In comparison with the baseline data, there was an improvement of 4.6 points in cognition assessed by ADAS-Cog (P = 0.000); an improvement of 2.7 points by MMSE (P = 0.000), an improvement of 1.5 points in behavior and mood by ADAS-non-Cog (P = 0.008) with 59.2% of the patients being on the mend clinically; and an improvement of 2.4 points by ADL (P = 0.001) with the capacity of ADL improved by at least 10% among 32.75% of the patients. 70% of the patients in huperzine Alpha group scored 1 approximately 3 points, and 27.8% of them scored 1 approximately 2 points by CIBIC-plus. The proportions of patients with an improvement of >/= 4 points by ADAS-Cog were 56.1% and 12.5% in the huperzine Alpha group and placebo group respectively (P = 0.000). The proportions of patients with an improvement of >/= 4 points by MMSE were 37.8% and 10.1% in the huperzine Alpha group and placebo group respectively (P = 0.000). The proportions of patients with an improvement of 1 approximately 3 points in global rating by CIBIC-plus were 59.2% and 40.6% in the huperzine Alpha group and placebo group respectively (P = 0.01). The proportions of patients with an improvement of >/= 10% points by ADL were 32.7% and 17.2% in the huperzine Alpha group and placebo group respectively (P = 0.01). The proportions of patients with an improvement of > 0 points by ADS-non-C0g were 70.0% and 36.3% in the huperzine Alpha group and placebo group respectively (P = 0.000). Mild and transient adverse events (edema of bilateral ankles and insomnia) were observed in 3% of huperzine Alpha treated patients. CONCLUSION: A safe and effective medicine, huperzine Alpha remarkably improves the cognition, behavior, ADL,and mood of AD patients.

Amadio M, Pascale A, Wang J, Ho L, Quattrone A, Gandy S, Haroutunian V, Racchi M, Pasinetti GM. · Department of Experimental and Applied Pharmacology and Centre of Excellence in Applied Biology, University of Pavia, Pavia, Italy. · J Alzheimers Dis. · Pubmed #19221430 No free full text.

Abstract: Neuronal ELAV (nELAV) proteins are RNA-binding proteins which play a physiological role in controlling gene expression in memory formation, and their alteration may contribute to cognitive impairment associated with neurodegenerative pathologies such as Alzheimer's disease (AD). Indeed, we found that the content of nELAV proteins is significantly decreased along with clinical dementia progression in the hippocampi of AD brains, where it inversely correlates with the amount of amyloid-beta (Abeta). To check the direct influence of Abeta on nELAV, we performed in vitro experiments using human SH-SY5Y cells, finding that Abeta(1-42) specifically determines nELAV proteins reduction. Since ADAM10 mRNA has the predicted sequences targeted by nELAV, we investigated whether Abeta, through nELAV proteins, could originate a vicious circle affecting amyloid-beta protein precursor (AbetaPP) processing. Immunoprecipitation experiments showed that indeed nELAV proteins bind to ADAM10 mRNA and that this binding is disrupted by Abeta(1-42) exposure, resulting in a decreased ADAM10 protein expression. ADAM10 protein diminution was also found in AD hippocampi. These data show for the first time the involvement of nELAV in AD pathology and suggest that their alteration may affect genes implicated in AbetaPP processing.

Qin W, Ho L, Wang J, Peskind E, Pasinetti GM. · Department of Psychiatry, Mount Sinai School of Medicine, New York, New York, USA. · PLoS One. · Pubmed #19159013 links to  free full text

Abstract: Alzheimer's disease (AD) is the most common cause of dementia among older people. At present, there is no cure for the disease and as of now there are no early diagnostic tests for AD. There is an urgency to develop a novel promising biomarker for early diagnosis of AD. Using surface-enhanced laser desorption ionization-mass spectrometry SELDI-(MS) proteomic technology, we identified and purified a novel 11.7-kDa metal- binding protein biomarker whose content is increased in the cerebrospinal fluid (CSF) and in the brain of AD dementia subjects as a function of clinical dementia. Following purification and protein-sequence analysis, we identified and classified this biomarker as S100A7, a protein known to be involved in immune responses. Using an adenoviral-S100A7 expression system, we continued to examine the potential role of S100A7 in AD amyloid neuropathology in in vitro model of AD. We found that the expression of exogenous S100A7 in primary cortico-hippocampal neuron cultures derived from Tg2576 transgenic embryos inhibits the generation of beta-amyloid (Abeta)(1-42) and Abeta(1-40) peptides, coincidental with a selective promotion of "non- amyloidogenic" alpha-secretase activity via promotion of ADAM (a disintegrin and metalloproteinase)-10. Finally, a selective expression of human S100A7 in the brain of transgenic mice results in significant promotion of alpha-secretase activity. Our study for the first time suggests that S100A7 may be a novel biomarker of AD dementia and supports the hypothesis that promotion of S100A7 expression in the brain may selectively promote alpha-secretase activity in the brain of AD precluding the generation of amyloidogenic peptides. If in the future we find that S1000A7 protein content in CSF is sensitive to drug intervention experimentally and eventually in the clinical setting, S100A7 might be developed as novel surrogate index (biomarker) of therapeutic efficacy in the characterization of novel drug agents for the treatment of AD.

Ho L, Chen LH, Wang J, Zhao W, Talcott ST, Ono K, Teplow D, Humala N, Cheng A, Percival SS, Ferruzzi M, Janle E, Dickstein DL, Pasinetti GM. · Department of Psychiatry, Mount Sinai School of Medicine, NY, USA. · J Alzheimers Dis. · Pubmed #19158422 No free full text.

Abstract: We recently found that moderate consumption of two unrelated red wines generate from different grape species, a Cabernet Sauvignon and a muscadine wine that are characterized by distinct component composition of polyphenolic compounds, significantly attenuated the development of Alzheimer's disease (AD)-type brain pathology and memory deterioration in a transgenic AD mouse model. Interestingly, our evidence suggests that the two red wines attenuated AD phenotypes through independent mechanisms. In particular, we previously found that treatment with Cabernet Sauvignon reduced the generation of AD-type amyloid-beta (Abeta) peptides. In contrast, evidence from our present study suggests that muscadine treatment attenuates Abeta neuropathology and Abeta-related cognitive deterioration in Tg2576 mice by interfering with the oligomerization of Abeta molecules to soluble high-molecular-weight Abeta oligomer species that are responsible for initiating a cascade of cellular events resulting in cognitive decline. Collectively, our observations suggest that distinct polyphenolic compounds from red wines may be bioavailable at the organism level and beneficially modulate AD phenotypes through multiple Abeta-related mechanisms. Results from these studies suggest the possibility of developing a "combination" of dietary polyphenolic compounds for AD prevention and/or therapy by modulating multiple Abeta-related mechanisms.

Yang X, Yang Y, Luo Y, Li G, Wang J, Yang ES. · Department of Pathophysiology, Institute of Neuroscience, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. · Cell Mol Neurobiol. · Pubmed #19137424 No free full text.

Abstract: Neurofilaments (NFs) are hyperphosphorylated and accumulate in Alzheimer's disease (AD) brains. In this study, employing the transgenic mouse model, we explored the effect of presenilin 1 (PS-1) mutation on the phosphorylation and distribution of NFs. Western blot analysis showed that there was a significant increase in the phosphorylation of NF-H and NF-M subunits with a concomitant increase in phosphorylated c-Jun N-terminal protein kinase 1/2 (JNK1/2) mitogen-activated protein kinase (MAPK) in hippocampus of PS-1 transgenic mice compared to that of wild-type littermates. Immunohistochemical analysis revealed that phosphorylated NFs accumulated throughout the hippocampal neurons of the transgenic mice. These findings suggest that PS-1 mutation may induce hyperphosphorylation and accumulation of NFs via a JNK1/2-involved mechanism.

Qin W, Zhao W, Ho L, Wang J, Walsh K, Gandy S, Pasinetti GM. · Department of Psychiatry, Mount Sinnai School of Medicine, New York, NY 10029, USA. · Ann N Y Acad Sci. · Pubmed #19076455 No free full text.

Abstract: Forkhead transcription factor FoxO3a, also known as DAF-16 in Caenorhabditis elegans, is a key regulator of the insulin receptor (IR)/insulin-like growth factor-I signaling pathway mediated extension of life span in worms and yeast. In this study, we report that calorie restriction (CR)-mediated activation of the IR signaling pathway leads to hyperphosphorylation of FoxO3a transcription factor and, consequently, its exclusion from the nucleus. This inactivation of FoxO3a activity is correlated with attenuation of Alzheimer's disease (AD)-type amyloid neuropathology and with preservation of spatial reference memory in the Tg2576 mouse model of AD. Further, in vitro studies reveal that exogenous expression of viral, triple-mutant, constitutively active FoxO3a resulting in increased nuclear FoxO3a activity in primary neuron cultures derived from Tg2576 mouse embryos, causally promotes AD amyloid-beta peptide (Abeta) levels by inhibiting nonamyloidogenic alpha-secretase activity, indicating the existence of an inverse correlation between FoxO3a activity and cerebral Abeta amyloidosis. Moreover, we report for the first time that the exclusion of the FoxO3a transcription factor from the nucleus in combination with inhibition of nuclear FoxO3a activity by SIRT1-mediated deacetylation in response to CR is a mechanism resulting in the repression of Rho-associated protein kinase-1 gene expression, thereby activating nonamyloidogenic alpha-secretase processing of the amyloid precursor protein and lowering Abeta generation. This study provides a novel metabolic pathway for prevention and/or treatment of AD.

Ono K, Condron MM, Ho L, Wang J, Zhao W, Pasinetti GM, Teplow DB. · Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7334, USA. · J Biol Chem. · Pubmed #18815129 No free full text.

Abstract: Epidemiological evidence suggests that moderate consumption of red wine reduces the incidence of Alzheimer disease (AD). To study the protective effects of red wine, experiments recently were executed in the Tg2576 mouse model of AD. These studies showed that a commercially available grape seed polyphenolic extract, MegaNatural-AZ (MN), significantly attenuated AD-type cognitive deterioration and reduced cerebral amyloid deposition (Wang, J., Ho, L., Zhao, W., Ono, K., Rosensweig, C., Chen, L., Humala, N., Teplow, D. B., and Pasinetti, G. M. (2008) J. Neurosci. 28, 6388-6392). To elucidate the mechanistic bases for these observations, here we used CD spectroscopy, photo-induced cross-linking of unmodified proteins, thioflavin T fluorescence, size exclusion chromatography, and electron microscopy to examine the effects of MN on the assembly of the two predominant disease-related amyloid beta-protein alloforms, Abeta40 and Abeta42. We also examined the effects of MN on Abeta-induced cytotoxicity by assaying 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide metabolism and lactate dehydrogenase activity in Abeta-treated, differentiated pheochromocytoma (PC12) cells. Initial studies revealed that MN blocked Abeta fibril formation. Subsequent evaluation of the assembly stage specificity of the effect showed that MN was able to inhibit protofibril formation, pre-protofibrillar oligomerization, and initial coil --> alpha-helix/beta-sheet secondary structure transitions. Importantly, MN had protective effects in assays of cytotoxicity in which MN was mixed with Abeta prior to peptide assembly or following assembly and just prior to peptide addition to cells. These data suggest that MN is worthy of consideration as a therapeutic agent for AD.

Kauwe JS, Wang J, Mayo K, Morris JC, Fagan AM, Holtzman DM, Goate AM. · Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA. · Neurogenetics. · Pubmed #18813964 No free full text.

Abstract: The use of quantitative endophenotypes in genetic studies may provide greater power, allowing for the use of powerful statistical methods and a biological model for the effects of the disease-associated genetic variation. Cerebrospinal fluid (CSF) amyloid beta (Abeta) levels are promising endophenotypes for late-onset Alzheimer's disease (LOAD) and show correlation with LOAD status and Abeta deposition. In this study, we investigated 29 single nucleotide polymorphisms (SNPs) positive in AlzGene ( http://www.alzgene.org ) meta-analyses, for association with CSF Abeta levels in 313 individuals. This study design makes it possible to replicate reported LOAD risk alleles while contributing novel information about the mechanism by which they might affect that risk. Alleles in ACE, APOE, BDNF, DAPK1, and TF are significantly associated with CSF Abeta levels. In vitro analysis of the TF SNP showed a change in secreted Abeta consistent with the CSF phenotype and known Alzheimer's disease variants, demonstrating the utility of this approach in identifying SNPs that influence risk for disease via an Abeta-related mechanism.

Gross GG, Feldman RM, Ganguly A, Wang J, Yu H, Guo M. · Department of Neurology, The David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America. · PLoS One. · Pubmed #18575606 links to  free full text

Abstract: The Amyloid Precursor Protein (APP) undergoes sequential proteolytic cleavages through the action of beta- and gamma-secretase, which result in the generation of toxic beta-amyloid (Abeta) peptides and a C-terminal fragment consisting of the intracellular domain of APP (AICD). Mutations leading to increased APP levels or alterations in APP cleavage cause familial Alzheimer's disease (AD). Thus, identification of factors that regulate APP steady state levels and/or APP cleavage by gamma-secretase is likely to provide insight into AD pathogenesis. Here, using transgenic flies that act as reporters for endogenous gamma-secretase activity and/or APP levels (GAMAREP), and for the APP intracellular domain (AICDREP), we identified mutations in X11L and ubiquilin (ubqn) as genetic modifiers of APP. Human homologs of both X11L (X11/Mint) and Ubqn (UBQLN1) have been implicated in AD pathogenesis. In contrast to previous reports, we show that overexpression of X11L or human X11 does not alter gamma-secretase cleavage of APP or Notch, another gamma-secretase substrate. Instead, expression of either X11L or human X11 regulates APP at the level of the AICD, and this activity requires the phosphotyrosine binding (PTB) domain of X11. In contrast, Ubqn regulates the levels of APP: loss of ubqn function leads to a decrease in the steady state levels of APP, while increased ubqn expression results in an increase in APP levels. Ubqn physically binds to APP, an interaction that depends on its ubiquitin-associated (UBA) domain, suggesting that direct physical interactions may underlie Ubqn-dependent regulation of APP. Together, our studies identify X11L and Ubqn as in vivo regulators of APP. Since increased expression of X11 attenuates Abeta production and/or secretion in APP transgenic mice, but does not act on gamma-secretase directly, X11 may represent an attractive therapeutic target for AD.

Wang J, Ho L, Zhao W, Ono K, Rosensweig C, Chen L, Humala N, Teplow DB, Pasinetti GM. · Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA. · J Neurosci. · Pubmed #18562609 links to  free full text

Abstract: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive impairments in memory and cognition. Extracellular accumulation of soluble high-molecular-weight (HMW) Abeta oligomers has been proposed to be largely responsible for AD dementia and memory deficits in the Tg2576 mice, a model of AD. In this study, we found that a naturally derived grape seed polyphenolic extract can significantly inhibit amyloid beta-protein aggregation into high-molecular-weight oligomers in vitro. When orally administered to Tg2576 mice, this polyphenolic preparation significantly attenuates AD-type cognitive deterioration coincidentally with reduced HMW soluble oligomeric Abeta in the brain. Our study suggests that grape seed-derived polyphenolics may be useful agents to prevent or treat AD.

Wang J, Hara H, Makifuchi T, Tabira T. · Department of Vascular Dementia Research, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 36-3 Genko, Morioka, Obu, Aichi, Japan. · J Alzheimers Dis. · Pubmed #18560128 No free full text.

Abstract: Tissue amyloid plaque immuno-reactive (TAPIR) antibody was better related to the effect of immunotherapy in Alzheimer's disease (AD) than ELISA antibody. Here we used a hybridoma technique to develop a TAPIR-like anti-human amyloid-beta (Abeta) mouse monoclonal antibody. The obtained monoclonal antibody, 3.4A10, was an IgG2b isotype and recognized N-terminal portion of Abeta1-42 without binding denatured or native amyloid-beta protein precursor. It had higher affinity to Abeta1-42 than to Abeta1-40 by Biacore affinity analysis and stained preferably the peripheral part of senile plaques and recognized the plaque core less than 4G8. It inhibited the Abeta1-42 fibril formation as well as degraded pre-aggregated Abeta1-42 peptide in a thioflavin T fluorescence spectrophotometry assay. The in vivo studies showed that 3.4A10 treatment decreased amyloid burden compared to the control group and significantly reduced Abeta42 levels rather than Abeta40 levels in brain lysates as well as the Abeta*56 oligomer (12mer) in TBS fraction of the brain lysates. 3.4A10 entered brain and decorated some plaques, which is surrounded by more Iba1-positive microglia. 3.4A10 therapy did not induce lymphocytic infiltration and obvious increase in microhemorrhage. We conclude that 3.4A10 is a TAPIR-like anti-human amyloid monoclonal antibody, and has a potential of therapeutic application for AD.

Kauwe JS, Wang J, Chakraverty S, Goate AM, Henao-Martinez AF. · Department of Psychiatry, Washington University School of Medicine, United States. · Neurosci Lett. · Pubmed #18479822 No free full text.

Abstract: Over 160 rare genetic variants in presenilin 1 (PSEN1) are known to cause Alzheimer's disease (AD). In this study we screened a family with early-onset AD for mutations in PSEN1 using direct DNA sequencing. We identified a novel PSEN1 genetic variant which results in the substitution of a Proline with an Alanine at codon 117 (P117A). The P117A variant was present in all demented individuals and fifty percent of at risk individuals. This variant occurs at a site where three other disease-causing variants have been previously observed. In vitro functional studies demonstrate that the P117A variant results in an altered Abeta42/total Abeta ratio consistent with an AD causing mutation. The P117A variant is a novel mutation in PSEN1, which causes early-onset AD in an autosomal dominant manner.

Vepsäläinen S, Hiltunen M, Helisalmi S, Wang J, van Groen T, Tanila H, Soininen H. · Department of Neurology, University Hospital and University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland. · Neurosci Lett. · Pubmed #18455870 No free full text.

Abstract: Expression levels of amyloid beta (Abeta)-degrading enzymes, insulin degrading enzyme (IDE) and neprilysin (NEP), were examined in transgenic mice with Alzheimer's disease-like neuropathology. After the development of first Abeta plaques in transgenic mice brain, cortical mRNA and protein levels of IDE were significantly up-regulated in the transgenic mice compared to their non-transgenic littermates. Up-regulation of IDE mRNA-levels occurred in parallel with increased Abeta40 and Abeta42 production. Additionally, a significant positive correlation was observed between protein levels of IDE and full-length amyloid precursor protein (APP) in the cerebral cortex. mRNA and protein levels of NEP were also nominally up-regulated in Tg mice compared to controls. These data may reflect up-regulation of the IDE and possibly of NEP expression in response to the Abeta accumulation.

Zheng MQ, Yin DZ, Zhang L, Lei B, Cheng DF, Cai HC, Han YJ, Wu MX, Zhang H, Wang J. · Research Center of Radiopharmaceuticals, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China. · Acta Pharmacol Sin. · Pubmed #18430362 links to  free full text

Abstract: AIM: To evaluate whether the newly-synthesized positron emission tomography (PET) tracer, [18F]2-(4'-(methylamino)phenyl)-6-fluoroethoxy- benzothiazole ([18F] O-FEt-PIB), could bind to beta-amyloid aggregates in a rat model of Alzheimer's disease (AD) using micro-PET. METHOD: [18F]O-FEt-PIB was synthesized and purified by radio HPLC. PET imaging was performed with a R4 rodent model scanner in 3 model and 3 control rats. Dynamic PET scans were performed for 40 min in each rat following an injection of approximately 37 MBq of [18F]O-FEt-PIB. Static scans were also performed for 15 min in each rat. PET data were reconstructed by a maximum posteriori probability algorithm. On the coronal PET images, regions of interest were respectively placed on the cortex, hemicerebrum [including the hippocampus and thalamus (HT)], and were guided by a 3-D digital map of the rat brain or the brain images of [18F]2-Deoxy-2-fluoro-D-glucose ([18F]FDG) in normal rats. Time-activity curves (TAC) were obtained for the cerebrum and cerebellum. The activity difference value (ADV) between 2 hemicerebrums was also calculated. RESULTS: The TAC for [18F]O-FEt-PIB in the cerebrum or cerebellum peaked early (at approximately 2 min), but washed out a little slowly. In the dynamic and static micro-PET images, increased radioactivity was found in the area of the right HT in the model rats where infused with beta-amyloid (1-40). No distinct difference of radioactivity was found between the right and left HT areas in the control rats. The ADV(HT) was approximately 14.6% in the AD model rats and approximately 4 times greater than that of the control rats (3.9%). CONCLUSION: To our knowledge, this study is the first to evaluate a small molecular PET probe for the beta-amyloid deposits in vivo using micro-PET imaging in an AD-injected rat model. The suitable biological characters showed that the tracer had potential to be developed as a probe for detecting beta-amyloid plaques in AD.

Wang B, Xie YC, Yang Z, Peng D, Wang J, Zhou S, Li S, Ma X. · National Research Institute for Family Planning, Beijing Friendship Hospital, Affiliate of the Capital University of Medical Sciences, Beijing, China. · Dement Geriatr Cogn Disord. · Pubmed #18408364 No free full text.

Abstract: Alzheimer's disease (AD) is a complex multifactorial disorder involving a number of genetic and environmental factors. Cystatin C (CST3), which belongs to the type II cystatin gene family, is a potent inhibitor of lysosomal proteinases. Immunohistochemical studies have demonstrated the colocalization of the b-amyloid (A-beta) and cystatin C peptides within arteriolar walls in the AD brain. The G73A polymorphism of the CST3 genemay be associated with AD development. To investigate a possible association between the CST3 G73A polymorphism and late-onset AD (LOAD) in Mainland Chinese, we examined 281 LOAD patients and 376 healthy controls. All subjects were genotyped for CST3 and apolipoprotein E (APOE). There were no significant differences in the CST3 genotype or allele frequencies between the cases and the controls. Likewise, with the stratification of the APOE epsilon4 status, no statistical difference was observed between the cases and the controls. Our findings suggest that this polymorphism may not represent an additional genetic risk factor for LOAD in Mainland Chinese.

Wang B, Zhou S, Yang Z, Xie YC, Wang J, Zhang P, Lv Z, Zheng C, Ma X. · National Research Institute for Family Planning, Beijing, 100081 China. · J Neurol Sci. · Pubmed #18396294 No free full text.

Abstract: Neuroinflammation and abnormal phosphorylation of TAU proteins have been implicated in the etiology of Alzheimer's disease (AD). Several studies have suggested the G-308A promoter polymorphism in one of the proinflammatory cytokine genes tumor necrosis factor-alpha (TNF-alpha) encoding TNF-alpha may be associated with AD pathogenesis. Association between the Q7R polymorphism in saitohin (STH), a gene nested within the intron of the Tau gene, has also been reported. To determine whether these two polymorphisms contribute to the risk for late-onset AD (LOAD) in Chinese, we have investigated 207 sporadic LOAD patients and 222 healthy controls. The associations of the AA genotype and A-allele with LOAD (chi(2) = 8.74, df = 1, P = 0.0031, and chi(2) = 4.47, df = 1, P = 0.035) were found. After stratifying by apolipoprotein E allele 4 (APOE epsilon4) status, increased LOAD risks associated with the AA genotype and A-allele only in the APOE epsilon4 non-carriers (chi(2) = 9.21, df = 1, P = 0.002; chi(2) = 10.02, df = 1, P = 0.0015) were seen. These results suggested that the TNF-alpha gene G-308A polymorphism might be a risk factor for LOAD and dependent on APOE epsilon4 status in Chinese. Homozygous Q/Q of STH Q7R polymorphism was the only one genotype found in either LOAD group or controls. No R allele was detected in LOAD and control groups. The extremely rare frequency of the ancestral R allele differs sharply from that observed in studies in the Caucasian population, suggesting obvious ethnic differences.

Wang B, Wang J, Zhou S, Tan S, He X, Yang Z, Xie YC, Li S, Zheng C, Ma X. · National Research Institute for Family Planning, Beijing, 100081, China. · J Neurol Sci. · Pubmed #18201725 No free full text.

Abstract: A functional polymorphism of mitochondrial aldehyde dehydrogenase gene (ALDH2 1/2 polymorphism) can influence the accumulation of acetaldehyde which may have a role in Alzheimer's disease (AD), and is widely prevalent among Mongoloids. Therefore ALDH2 1/2 polymorphism may represent a good candidate for genetic risk factors for AD, especially in East Asian. A case-control study from Japan found that ALDH2*2 was associated with late-onset AD (LOAD), interacting synergistically with the presence of the apolipoprotein E allele 4 (APOE epsilon4). But the subsequent studies in Koreans didn't find the similar result. To determine whether the ALDH2 gene 1/2 polymorphism contributes to the risk for LOAD in Chinese, we have investigated 188 sporadic LOAD patients and 223 healthy controls from Chinese. A significantly increased risk of AD in the carriers of ALDH2*2 allele (OR=3.11, 95% CI 2.06-4.69, P<0.001) was observed. After stratifying by APOE epsilon4 status, increased LOAD risks associated with the ALDH2 2 allele carriers only in the APOE epsilon4 non-carriers (chi2=31.79, df=1, P<0.001) and with the 2-allele in either groups (chi2=6.64 df=1, P=0.0099 and chi2=37.38, df=1, P<0.001) were seen. These results suggested that the ALDH2 gene 1/2 polymorphism might be a risk factor for LOAD and dependent on APOE epsilon4 status in Chinese.

Wang B, Tan S, Yang Z, Xie YC, Wang J, Zhou S, Li S, Zheng C, Ma X. · Center for Genetics, National Research Institute for Family Planning, 12, Dahuisi Road, Haidian, Beijing 100081, China. · J Mol Neurosci. · Pubmed #18183499 No free full text.

Abstract: The oxidative stress caused by nitric oxide (NO) in the brain has been proposed as a pathogenic mechanism in Alzheimer's disease. Endothelial NO synthase (ecNOS) produces the majority of circulating NO. The biological functional and genetic association studies suggested that the Glu298Asp polymorphism of the ecNOS gene (NOS3) may be a genetic risk factor for late-onset Alzheimer's disease (LOAD). To investigate an association between the NOS31 Glu298Asp polymorphism and sporadic LOAD in Chinese, we examined 338 LOAD patients and 378 healthy controls. The associations of the Glu/Glu genotype and Glu allele with LOAD (chi2 = 9.12, df = 1, P = 0.003 by genotype; chi2 = 8.37, df = 1, P = 0.038 by allele) were found. After stratifying by apolipoprotein E allele 4 (APOE epsilon 4) status, increased LOAD risks associated with the Glu/Glu genotype and Glu allele only in the APOE epsilon 4 noncarriers (chi2 = 6.28, df = 1, P = 0.012 by genotype; chi2 = 5.62, df = 1, P = 0.018 by allele) were seen. These results suggest that the NOS3 gene Glu298Asp polymorphism might be a risk factor for LOAD and dependent on APOE epsilon 4 status in Chinese.

Yang X, Yang Y, Li G, Wang J, Yang ES. · The Jockey Club MRI Center, The University of Hong Kong, Hong Kong, China. · J Mol Neurosci. · Pubmed #18181031 No free full text.

Abstract: One of the neuropathological features of Alzheimer's disease (AD) is the deposition of senile plaques containing beta-amyloid (A beta). There is limited evidence for the treatment to arrest A beta pathology of AD. In our present study, we tested the effect of coenzyme Q10 (CoQ10), an endogenous antioxidant and a powerful free radical scavenger, on A beta in the aged transgenic mice overexpressing Alzheimer presenilin 1-L235P (leucine-to-proline mutation at codon 235, 16-17 months old). The treatment by feeding the transgenic mice with CoQ10 for 60 days (1,200 mg kg(-1) day(-1)) partially attenuated A beta overproduction and intracellular A beta deposit in the cortex of the transgenic mice compared with the age-matched untreated transgenic mice. Meanwhile, an increased oxidative stress reaction was detected as evidenced by elevated level of malondialdehyde (MDA) and decreased activity of superoxide dismutase (SOD) in the transgenic mice relative to the wild-type mice, and supplementation of CoQ10 partially decreased MDA level and upregulated the activity of SOD. The results indicate that oxidative stress is enhanced in the brain of the transgenic mice, that this enhancement may further promote A beta 42 overproduction in a vicious formation, and that CoQ10 would be beneficial for the therapy of AD.

Luo Y, Zhou X, Yang X, Wang J. · Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. · Neuroreport. · Pubmed #18007203 No free full text.

Abstract: Epidemiological and clinical data suggest that homocysteine (Hcy) may increase the risk of Alzheimer's disease, but the underlying mechanisms are elusive. To investigate the effect of Hcy on phosphorylation of tau, we injected Hcy into the lateral cerebral ventricle of rats. We found that level of the hyperphosphorylated tau at PHF-1 (Ser396/404) and tau-1 (Ser198/199/202) epitopes was elevated prominently at 6, 9, and 12 h after the injection, and it was recovered to normal at 24 h. Simultaneously, the level of protein phosphatase-2A catalytic subunit (PP-2Ac) was reduced markedly as compared with control. These results imply that Hcy may induce hyperphosphorylation of tau with PP-2Ac involved mechanism.