Selection of lansoprazole from an FDA-approved drug library to inhibit the Alzheimer's disease seed-dependent formation of tau aggregates.

The efficacy of current treatments is still insufficient for Alzheimer's disease (AD), the most common cause of Dementia. Out of the two pathological hallmarks of AD amyloid-ß plaques and neurofibrillary tangles, comprising of tau protein, tau pathology strongly correlates with the symptoms of AD. Previously, screening for inhibitors of tau aggregation that target recombinant tau aggregates have been attempted. Since a recent cryo-EM analysis revealed distinct differences in the folding patterns of heparin-induced recombinant tau filaments and AD tau filaments, this study focused on AD seed-dependent tau aggregation in drug repositioning for AD. We screened 763 compounds from an FDA-approved drug library using an AD seed-induced tau aggregation in SH-SY5Y cell-based assay. In the first screening, 180 compounds were selected, 72 of which were excluded based on the results of lactate dehydrogenase assay. In the third screening with evaluations of soluble and insoluble tau, 38 compounds were selected. In the fourth screening with 3 different AD seeds, 4 compounds, lansoprazole, calcipotriene, desogestrel, and pentamidine isethionate, were selected. After AD seed-induced real-time quaking-induced conversion, lansoprazole was selected as the most suitable drug for repositioning. The intranasal administration of lansoprazole for 4 months to AD seed-injected mice improved locomotor activity and reduced both the amount of insoluble tau and the extent of phosphorylated tau-positive areas. Alanine replacement of the predicted binding site to an AD filament indicated the involvement of Q351, H362, and K369 in lansoprazole and C-shaped tau filaments. These results suggest the potential of lansoprazole as a candidate for drug repositioning to an inhibitor of tau aggregate formation in AD.

High-fat diet-induced activation of SGK1 promotes Alzheimer's disease-associated tau pathology.

Type 2 diabetes mellitus (T2DM) has long been considered a risk factor for Alzheimer's disease (AD). However, the molecular links between T2DM and AD remain obscure. Here, we reported that serum-/glucocorticoid-regulated kinase 1 (SGK1) is activated by administering a chronic high-fat diet (HFD), which increases the risk of T2DM, and thus promotes Tau pathology via the phosphorylation of tau at Ser214 and the activation of a key tau kinase, namely, GSK-3ß, forming SGK1-GSK-3ß-tau complex. SGK1 was activated under conditions of elevated glucocorticoid and hyperglycemia associated with HFD, but not of fatty acid-mediated insulin resistance. Elevated expression of SGK1 in the mouse hippocampus led to neurodegeneration and impairments in learning and memory. Upregulation and activation of SGK1, SGK1-GSK-3ß-tau complex were also observed in the hippocampi of AD cases. Our results suggest that SGK1 is a key modifier of tau pathology in AD, linking AD to corticosteroid effects and T2DM.

Learning Deficits Accompanied by Microglial Proliferation After the Long-Term Post-Injection of Alzheimer's Disease Brain Extract in Mouse Brains.

BACKGROUND: Human tauopathy brain injections into the mouse brain induce the development of tau aggregates, which spread to functionally connected brain regions; however, the features of this neurotoxicity remain unclear. One reason may be short observational periods because previous studies mostly used mutated-tau transgenic mice and needed to complete the study before these mice developed neurofibrillary tangles. OBJECTIVE: To examine whether long-term incubation of Alzheimer's disease (AD) brain in the mouse brain cause functional decline. METHODS: We herein used Tg601 mice, which overexpress wild-type human tau, and non-transgenic littermates (NTg) and injected an insoluble fraction of the AD brain into the unilateral hippocampus. RESULTS: After a long-term (17-19 months) post-injection, mice exhibited learning deficits detected by the Barnes maze test. Aggregated tau pathology in the bilateral hippocampus was more prominent in Tg601 mice than in NTg mice. No significant changes were observed in the number of Neu-N positive cells or astrocytes in the hippocampus, whereas that of Iba-I-positive microglia increased after the AD brain injection. CONCLUSION: These results potentially implicate tau propagation in functional decline and indicate that long-term changes in non-mutated tau mice may reflect human pathological conditions.

Strain-specific clearance of seed-dependent tau aggregation by lithium-induced autophagy.

Different conformational strains of tau have been implicated in the clinicopathological heterogeneity of tauopathies. In this study, we hypothesized that distinct strains are degraded in a different manner. Lithium, a drug for bipolar disorder, had previously been reported to reduce aggregation-prone protein content by promoting autophagy. Here, we assessed the effects of lithium on tau aggregates using different tauopathy brain seeds. SH-SY5Y cells were transfected with C-terminal tau fragment Tau-CTF24 (residues 243-441), and Alzheimer's disease (AD), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD) brain seeds were introduced. After 48-h lithium treatment, sarkosyl-insoluble fractions were prepared. Lithium treatment was found to reduce the amount of insoluble tau and p62, and increase LC3-II levels along with the number of autophagic vacuoles in AD-seeded cells. The effects were lower in case of CBD seeds, and comparable between PSP and AD seeds. An inhibitor of myo-inositol monophosphatase (IMPase) also demonstrated similar effects. Overall, the study suggested that aggregated tau protein is degraded by lithium-induced autophagy, influencing IMPase in a strain-specific manner.

Asparagine residue 368 is involved in Alzheimer's disease tau strain-specific aggregation.

In tauopathies, tau forms pathogenic fibrils with distinct conformations (termed "tau strains") and acts as an aggregation "seed" templating the conversion of normal tau into isomorphic fibrils. Previous research showed that the aggregation core of tau fibril covers the C-terminal region (243-406 amino acids (aa)) and differs among the diseases. However, the mechanisms by which distinct fibrous structures are formed and inherited via templated aggregation are still unknown. Here, we sought to identify the key sequences of seed-dependent aggregation. To identify sequences for which deletion reduces tau aggregation, SH-SY5Y cells expressing a series of 10 partial deletion (Del 1-10, covering 244-400 aa) mutants of tau-CTF24 (243-441 aa) were treated with tau seeds prepared from a different tauopathy patient's brain (Alzheimer's disease, progressive supranuclear palsy, and corticobasal degeneration) or recombinant tau, and then seed-dependent tau aggregation was assessed biochemically. We found that the Del 8 mutant lacking 353-368 aa showed significantly decreased aggregation in both cellular and in vitro models. Furthermore, to identify the minimum sequence responsible for tau aggregation, we systematically repeated cellular tau aggregation assays for the delineation of shorter deletion sites and revealed that Asn-368 mutation suppressed tau aggregation triggered by an AD tau seed, but not using other tauopathy seeds. Our study suggested that 353-368 aa is a novel aggregation-responsible sequence other than PHF6 and PHF6*, and within this sequence, the Asn-368 residue plays a role in strain-specific tau aggregation in different tauopathies.

Phospho-Tau Bar Code: Analysis of Phosphoisotypes of Tau and Its Application to Tauopathy.

Tau is a microtubule-associated protein which regulates the assembly and stability of microtubules in the axons of neurons. Tau is also a major component of neurofibrillary tangles (NFTs), a pathological hallmark in Alzheimer's disease (AD). A characteristic of AD tau is hyperphosphorylation with more than 40 phosphorylation sites. Aggregates of hyperphosphorylated tau are also found in other neurodegenerative diseases which are collectively called tauopathies. Although a large number of studies have been performed on the phosphorylation of AD tau, it is not known if there is disease-specific phosphorylation among tauopathies. This is due to the lack of a proper method for analyzing tau phosphorylation in vivo. Most previous phosphorylation studies were conducted using a range of phosphorylation site-specific antibodies. These studies describe relative changes of different phosphorylation sites, however, it is hard to estimate total, absolute and collective changes in phosphorylation. To overcome these problems, we have recently applied the Phos-Tag technique to the analysis of tau phosphorylation in vitro and in vivo. This method separates tau into many bands during SDS-PAGE depending on its phosphorylation states, creating a bar code appearance. We propose calling this banding pattern of tau the "phospho-tau bar code." In this review article, we describe what is newly discovered regarding tau phosphorylation through the use of the Phos-Tag. We would like to propose its use for the postmortem diagnosis of tauopathy which is presently done by immunostaining diseased brains with anti-phospho-antibodies. While Phos-tag SDS-PAGE, like other biochemical assays, will lose morphological information, it could provide other types of valuable information such as disease-specific phosphorylation.

Establishment of a genome-wide and quantitative protocol for assessment of transcriptional activity at human retrotransposon L1 antisense promoters.

Long interspersed element 1 (L1) retrotransposon sequences are widespread in the human genome, occupying ~500,000 locations. The majority of L1s have lost their retrotransposition capability, although a significant population of human L1s maintains bidirectional transcriptional activity from the internal promoter. While the sense promoter drives transcription of the entire L1 mRNA and leads to L1 retrotransposition, the antisense promoter (ASP) transcribes L1-gene chimeric RNAs that include neighboring exon sequences. Activation mechanisms and functional impacts of L1ASP transcription are thought to vary at every L1ASP location. To explore the locus-specific regulation and function of L1ASP transcription, quantitative methodology is necessary for identifying the genomic positions of highly active L1ASPs on a genome-wide scale. Here, we employed deep-sequencing techniques and built a 3' RACE-based experimental and bioinformatics protocol, named the L1 antisense transcriptome protocol (LATRAP). In LATRAP, the PCR primer and the read mapping scheme were designed to reduce false positives and negatives, which may have been included as hits in previous cloning studies. LATRAP was here applied to the A549 human lung cancer cell line, and 313 L1ASP loci were detected to have transcriptional activity but differed in the number of mapped reads by four orders of magnitude. This indicates that transcriptional activities of the individual L1ASPs can vary greatly and that only a small population of L1ASP loci is active within individual nuclei. LATRAP is the first experimental method for ranking L1ASPs according to their transcriptional activity and will thus open a new avenue to unveiling the locus-specific biology of L1ASPs.

In vivo regulation of glycogen synthase kinase 3ß activity in neurons and brains.

Glycogen synthase kinase 3ß (GSK3ß) is a multifunctional protein kinase involved in many cellular activities including development, differentiation and diseases. GSK3ß is thought to be constitutively activated by autophosphorylation at Tyr216 and inactivated by phosphorylation at Ser9. The GSK3ß activity has previously been evaluated by inhibitory Ser9 phosphorylation, but it does not necessarily indicate the kinase activity itself. Here, we applied the Phos-tag SDS-PAGE technique to the analysis of GSK3ß phosphoisotypes in cells and brains. There were three phosphoisotypes of GSK3ß; double phosphorylation at Ser9 and Tyr216, single phosphorylation at Tyr216 and the nonphosphorylated isotype. Active GSK3ß with phosphorylation at Tyr216 represented half or more of the total GSK3ß in cultured cells. Although levels of phospho-Ser9 were increased by insulin treatment, Ser9 phosphorylation occurred only in a minor fraction of GSK3ß. In mouse brains, GSK3ß was principally in the active form with little Ser9 phosphorylation, and the phosphoisotypes of GSK3ß changed depending on the regions of the brain, age, sex and disease conditions. These results indicate that the Phos-tag SDS-PAGE method provides a simple and appropriate measurement of active GSK3ß in vivo, and the activity is regulated by the mechanism other than phosphorylation on Ser9.

Age-related effects and gender differences in Japanese healthy controls for [123I] FP-CIT SPECT.

OBJECTIVE: Dopamine transporter (DAT) imaging with [123I]FP-CIT (DaTSCAN) is a widely used diagnostic tool for Parkinsonism and dementia. Since it was approved by the Japanese Ministry of Health, Labor, and Welfare in 2013, there have been no articles focusing on a Japanese normal population. The aim of this study was to examine the effect of aging and gender on DAT availability in Japanese people. METHODS: SPECT imaging of 30 healthy Japanese controls (17 males, 13 females; range 50-86 years, mean 70 years) was performed. SPECT images were reconstructed using a three-dimensional order subset expectation maximization (OSEM) algorithm with correction of the point spread function and scatter correction, without attenuation correction. The specific binding ratio (SBR) was calculated by DATview software. Statistical analyses were performed using linear regression analysis, analysis of variance, and multiple comparison analysis. RESULTS: A strong correlation between the SBR and age was observed. The correlation coefficient in males and females were -0.566 and -0.502, respectively. The analysis of variance revealed that aging led to a decline of the SBR, and a significant difference (p = 0.005) was observed among generations. Gender also affected the SBR, and there was a significant difference between males and females (p = 0.036). The SBR in females was higher than in males. Consequently, the multiple comparison revealed a significant difference between 50s and 70s (p = 0.015) and 50s and 80s (p = 0.006). CONCLUSIONS: This is the first [123I]FP-CIT SPECT study on subjects with normal dopamine function in Asian countries. This study provides a database of [123I]FP-CIT SPECT in Japanese healthy controls. Higher DAT availability was found in women than in men. An average age-related decline in DAT availability of 8.9% was found in both genders. The data collected in this study would be helpful for Japanese physicians to make a differential diagnosis in Parkinsonian syndrome. The registration identification number for this study is UMIN000018045.

[A Case of Right Pyonephrosis Caused by Renal Pelvic Cancer].

A 47-year-old woman who was diagnosed with right pyelonephritis by a local physician, but failed to respond to antimicrobial chemotherapy, was referred to our hospital. Here, the diagnosis of right pyonephrosis was confirmed byabdominal computed tomography(CT). Retrograde pyelography(RP) revealed a severe stricture at the ureteropelvic junction, and it was considered difficult to advance a guidewire through the stricture. Urine cytologywas pseudo-positive ; thus, the possibilityof a malignant tumor of the urinarytract could not be ruled out. Therefore, right nephroureterectomywas performed. The final, histopathological diagnosis was urothelial carcinoma, (G2, pT3). After surgery, the signs and symptoms of the infection were rapidlyameliorated ; however, swelling of the lymph-nodes between the aorta and vena cava was observed, which was considered to be metastasis. Therefore, 4 courses of gemcitabine ＋cisplatin therapywere administered, which resulted in complete resolution of the lymph-node swelling. The patient has remained free of recurrence for 2 years after surgery.

Quantitative and combinatory determination of in situ phosphorylation of tau and its FTDP-17 mutants.

Tau is hyperphosphorylated in the brains of patients with tauopathies, such as Alzheimer's disease and frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). However, neither the mechanism of hyperphosphorylation nor its contribution to pathogenesis is known. We applied Phos-tag SDS-PAGE, a phosphoaffinity electrophoresis, to the analysis of tau phosphorylation in vitro by Cdk5, in cultured cells and in mouse brain. Here, we found that Cdk5-p25 phosphorylated tau in vitro at Ser404, Ser235, Thr205 and Ser202 in this order. In contrast in cultured cells, Ser404 was preferentially phosphorylated by Cdk5-p35, whereas Thr205 was not phosphorylated. Ser202 and Ser235 were phosphorylated by endogenous kinases. Tau exhibited ~12 phosphorylation isotypes in COS-7 cells with different combinations of phosphorylation at Thr181, Ser202, Thr231, Ser235 and Ser404. These phosphorylation sites were similar to tau phosphorylated in mouse brains. FTDP-17 tau with a mutation in the C-terminal region had different banding patterns, indicating a different phosphorylation pattern. In particular, it was clear that the R406W mutation causes loss of Ser404 phosphorylation. These results demonstrate the usefulness of the Phos-tag technique in the quantitative analysis of site-specific in vivo phosphorylation of tau and provide detailed information on in situ combinatory phosphorylation of tau.

[Possible Diagnosis of Segmental Ureteritis Due to an IgG4-Related Disease that Improved with Steroid Therapy].

A 70-year-old woman was referred to our department after being diagnosed with right hydronephrosis on the basis of computed tomography (CT). CT and magnetic resonance imaging results indicated circumferential wall thickening in the right middle ureter. A retrograde pyelogram revealed an approximately 20 mm stricture in the right middle ureter, and urine cytology results were pseudo-positive. Ureteroscopy was performed due to suspicion of a malignant tumor of the urinary tract, but no malignant lesions were found. Biopsy results showed only the pathology of nonspecific ureteritis, and a diagnosis could not be made even with immunostaining. The patient's blood IgG4 levels were high (317 mg/dl). Based on the diagnostic criteria, the patient was given a possible diagnosis of an IgG4-related disease and treated by the placement ofa ureteral stent and administration of steroid therapy. After starting treatment, blood IgG4 levels decreased and the imaging findings showed improvement. The ureteral stent was removed in the 12th week, and steroid administration was discontinued in the 14th week. No recurrence has since been noted.

Region-Specific Vulnerability to Oxidative Stress, Neuroinflammation, and Tau Hyperphosphorylation in Experimental Diabetes Mellitus Mice.

Recent epidemiological evidence suggests that diabetes mellitus (DM) is a risk factor for Alzheimer's disease (AD). One of the pathological hallmarks of AD is hyperphosphorylated tau protein, which forms neurofibrillary tangles. Oxidative stress and the activation of inflammatory pathways are features that are associated with both DM and AD. However, the brain region specificity of AD-related neurodegeneration, which mainly occurs in the hippocampus while the cerebellum is relatively unaffected, has not yet been clarified. Therefore, we used experimental DM mice (caused by an intraperitoneal injection of streptozotocin [STZ]) to determine whether these neurodegeneration-associated mechanisms were associated with region-specific selective vulnerability or tau phosphorylation. The hippocampus, midbrain, and cerebellum of aged (14 to 18 months old) non-transgenic (NTg) and transgenic mice overexpressing wild-type human tau (Tg601 mice) were evaluated after a treatment with STZ. The STZ injection increased reactive oxygen species, lipid peroxidation markers such as 4-hydroxynonenal and malondialdehyde in the hippocampus, but not in the midbrain or cerebellum. The STZ treatment also increased the number of Iba-1-positive and CD68-positive microglial cells, astrocytes, and IL-1ß, IL-6, IL-10, and IL-18 levels in the hippocampus, but not in the midbrain or cerebellum. Tau hyperphosphorylation was also enhanced in the hippocampus, but not in the midbrain or cerebellum. When the effects of STZ were compared between Tg601 and NTg mice, microglial proliferation and elevations in IL-6 and phosphorylated tau were higher in Tg601 mice. These results suggest that neuroinflammation and oxidative stress in STZ-treated mice are associated with tau hyperphosphorylation, which may contribute to selective neurodegeneration in human AD.

Short-term treadmill exercise increased tau insolubility and neuroinflammation in tauopathy model mice.

Physical exercise has been identified as a preventive measure for Alzheimer's disease (AD), one of the neuropathological hallmarks of which, neurofibrillary tangles, consist of hyperphosphorylated insoluble tau. Previous studies demonstrated that long-term treadmill exercise reduced tau hyperphosphorylation and insolubility; however, whether short-term treadmill exercise (STE) alters tau modifications currently remains unknown. In the present study, we attempted to characterize the effects of STE on tau solubility and determine its relationship with neuroinflammation using tauopathy model mice (Tg601), which express wild-type human tau. The results obtained showed that 3 weeks of non-shock treadmill exercise in Tg601 and non-transgenic female mice markedly increased insoluble tau. An analysis of phosphorylation patterns indicated that changes in tau solubility were related to an increase in phosphorylation at the tau C-terminal end. The results of immunohistochemical analyses revealed that STE increased the number of Iba-1-positive microglial cells in the hippocampus. Elevations in the levels of the lipid peroxidation markers, 4-hydroxy-trans-2-noneal and malondialdehyde, indicated the presence of oxidative stress. Moreover, higher levels of cytokines, IL-1ß and IL-18, and chemokines, CXCL-1 and CXCL-12, supported neuroinflammation.

The Abundance of Nonphosphorylated Tau in Mouse and Human Tauopathy Brains Revealed by the Use of Phos-Tag Method.

Tauopathies are neurodegenerative diseases characterized by aggregates of hyperphosphorylated tau. Previous studies have identified many disease-related phosphorylation sites on tau. However, it is not understood how tau is hyperphosphorylated and what extent these sites are phosphorylated in both diseased and normal brains. Most previous studies have used phospho-specific antibodies to analyze tau phosphorylation. These results are useful but do not provide information about nonphosphorylated tau. Here, we applied the method of Phos-tag SDS-PAGE, in which phosphorylated tau was separated from nonphosphorylated tau in vivo. Among heterogeneously phosphorylated tau species in adult mouse brains, the nonphosphorylated 0N4R isoform was detected most abundantly. In contrast, perinatal tau and tau in cold water-stressed mice were all phosphorylated with a similar extent of phosphorylation. In normal elderly human brains, nonphosphorylated 0N3R and 0N4R tau were most abundant. A slightly higher phosphorylation of tau, which may represent the early step of hyperphosphorylation, was increased in Alzheimer disease patients at Braak stage V. Tau with this phosphorylation state was pelleted by centrifugation, and sarkosyl-soluble tau in either Alzheimer disease or corticobasal degeneration brains showed phosphorylation profiles similar to tau in normal human brain, suggesting that hyperphosphorylation occurs in aggregated tau. These results indicate that tau molecules are present in multiple phosphorylation states in vivo, and nonphosphorylated forms are highly expressed among them.

The twenty-four KDa C-terminal tau fragment increases with aging in tauopathy mice: implications of prion-like properties.

The truncated tau protein is a component of the neurofibrillary tangles found in the brains with tauopathies. However, the molecular mechanisms by which the truncated tau fragment causes neurodegeneration remain unknown. Tau pathology was recently suggested to spread through intercellular propagation, and required the formation of 'prion-like' species. We herein identified a new fragment of the tau protein that consisted of four binding domains and a C-terminal tail (Tau-CTF24), but lacked the N-terminal projection domain, and found that it increased with aging in tauopathy model mice (Tg601). Tau-CTF24-like fragments were also present in human brains with tauopathies. A mass spectroscopic analysis revealed that Tau-CTF24 was cleaved behind R242. The digestion of full-length tau (Tau-FL) by calpain produced Tau-CTF24 in vitro and calpain activity increased in old Tg601. Recombinant Tau-CTF24 accelerated heparin-induced aggregation and lost the ability to promote microtubule assembly. When insoluble tau from diseased brains or aggregated recombinant tau was introduced as seeds into SH-SY5Y cells, a larger amount of insoluble tau was formed in cells overexpressing Tau-CTF24 than in those overexpressing Tau-FL. Furthermore, lysates containing the Tau-CTF24 inclusion propagated to naive tau-expressing cells more efficiently than those containing the Tau-FL inclusion. Immunoblot and confocal microscopic analyses revealed that aggregated Tau-CTF24 bound to cells more rapidly and abundantly than aggregated Tau-FL. Our results suggest that Tau-CTF24 contributes to neurodegeneration by enhancing prion-like propagation as well as deteriorating the mechanisms involved in microtubule function.

Physiological and pathological phosphorylation of tau by Cdk5.

Hyperphosphorylation of microtubule-associated protein tau is one of the major pathological events in Alzheimer's disease (AD) and other related neurodegenerative diseases, including frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). Mutations in the tau gene MAPT are a cause of FTDP-17, and the mutated tau proteins are hyperphosphorylated in patient brains. Thus, it is important to determine the molecular mechanism of hyperphosphorylation of tau to understand the pathology of these diseases collectively called tauopathy. Tau is phosphorylated at many sites via several protein kinases, and a characteristic is phosphorylation at Ser/Thr residues in Ser/Thr-Pro sequences, which are targeted by proline-directed protein kinases such as ERK, GSK3ß, and Cdk5. Among these kinases, Cdk5 is particularly interesting because it could be abnormally activated in AD. Cdk5 is a member of the cyclin-dependent kinases (Cdks), but in contrast to the major Cdks, which promote cell cycle progression in proliferating cells, Cdk5 is activated in post-mitotic neurons via the neuron-specific activator p35. Cdk5-p35 plays a critical role in brain development and physiological synaptic activity. In contrast, in disease brains, Cdk5 is thought to be hyperactivated by p25, which is the N-terminal truncated form of p35 and is generated by cleavage with calpain. Several reports have indicated that tau is hyperphosphorylated by Cdk5-p25. However, normal and abnormal phosphorylation of tau by Cdk5 is still not completely understood. In this article, we summarize the physiological and pathological phosphorylation of tau via Cdk5.

Lithium and autophagy.

Lithium, a drug used to treat bipolar disorders, has a variety of neuroprotective mechanisms, including autophagy regulation, in various neuropsychiatric conditions. In neurodegenerative diseases, lithium enhances degradation of aggregate-prone proteins, including mutated huntingtin, phosphorylated tau, and α-synuclein, and causes damaged mitochondria to degrade, while in a mouse model of cerebral ischemia and Alzheimer's disease autophagy downregulation by lithium is observed. The signaling pathway of lithium as an autophagy enhancer might be associated with the mammalian target of rapamycin (mTOR)-independent pathway, which is involved in myo-inositol-1,4,5-trisphosphate (IP3) in Huntington's disease and Parkinson's disease. However, the mTOR-dependent pathway might be involved in inhibiting glycogen synthase kinase-3ß (GSK3ß) in other diseases. Lithium's autophagy-enhancing property may contribute to the therapeutic benefit of patients with neuropsychiatric disorders.

Polymorphic L1 retrotransposons are frequently in strong linkage disequilibrium with neighboring SNPs.

L1 retrotransposons have been the major driver of structural variation of the human genome. L1 insertion polymorphism (LIP)-mediated genomic variation can alter the transcriptome and contribute to the divergence of human phenotypes. To assess this possibility, a genome-wide association study (GWAS) including LIPs is required. Toward this ultimate goal, the present study examined linkage disequilibrium between six LIPs and their neighboring single nucleotide polymorphisms (SNPs). Genomic PCR and sequencing of L1-plus and -minus alleles from different donors revealed that all six LIPs were in strong linkage disequilibrium with at least one SNP. In addition, comparison of syntenic regions containing the identified SNP nucleotides was performed among modern humans (L1-plus and -minus alleles), archaic humans and non-human primates, revealing two different evolutionary schemes that might have resulted in the observed strong SNP-LIP linkage disequilibria. This study provides an experimental framework and guidance for a future SNP-LIP integrative GWAS.

Cerebrospinal fluid levels of phosphorylated tau and Aß1-38/Aß1-40/Aß1-42 in Alzheimer's disease with PS1 mutations.

We studied seven cases of Alzheimer's disease (AD). Six of the patients had presenilin 1 (PS1) mutations (PS1AD). Three novel PS1 mutations (T99A, H131R and L219R) and three other missense mutations (M233L, H163R and V272A) were found in the PS1AD group. We measured the levels of phosphorylated tau (ptau-181, ptau-199) and Aß (Aß1-42, Aß1-40 and Aß1-38) in the cerebrospinal fluid (CSF) of PS1AD patients, early-onset sporadic AD (EOSAD), late-onset sporadic AD (LOSAD) and non-demented subjects (ND). The CSF levels of Aß1-42 in the three AD groups were significantly lower than those of the ND group (p < 0.0001). CSF levels of Aß1-42 in the PS1AD group were significantly lower than those in the two sporadic AD groups. The Aß1-40 and Aß1-38 levels in the CSF of the PS1AD group were significantly lower than those of the three other groups (p < 0.0001, respectively). The levels of Aß1-40, Aß1-38 and Aß1-42 in the CSF of the PS1AD group remained lower than those of the ND group for 4 years. Not only CSF Aß1-42, but also Aß1-40 and Aß1-38 decreased in the advanced stages of PS1AD.