Antivirals Reduce the Formation of Key Alzheimer's Disease Molecules in Cell Cultures Acutely Infected with Herpes Simplex Virus Type 1

Alzheimer's disease (AD) afflicts around 20 million people worldwide and so there is an urgent need for effective treatment. Our research showing that herpes simplex virus type 1 (HSV1) is a risk factor for AD for the brains of people who possess a specific genetic factor and that the virus causes accumulation of key AD proteins (β-amyloid (Aβ) and abnormally phosphorylated tau (P-tau)), suggests that anti-HSV1 antiviral agents might slow AD progression. However, currently available antiviral agents target HSV1 DNA replication and so might be successful in AD only if Aβ and P-tau accumulation depend on viral DNA replication. Therefore, we investigated firstly the stage(s) of the virus replication cycle required for Aβ and P-tau accumulation, and secondly whether antiviral agents prevent these changes using recombinant strains of HSV1 that progress only partly through the replication cycle and antiviral agents that inhibit HSV1 DNA replication. By quantitative immunocytochemistry we demonstrated that entry, fusion and uncoating of HSV1, are insufficient to induce Aβ and P-tau production. We showed also that none of the “immediate early” viral proteins is directly responsible, and that Aβ and P-tau are produced at a subsequent stage of the HSV1 replication cycle. Importantly, the anti-HSV1 antiviral agents acyclovir, penciclovir and foscarnet reduced Aβ and P-tau accumulation, as well as HSV1, with foscarnet being less effective in each case. P-tau accumulation was found to depend on HSV1 DNA replication, whereas Aβ accumulation was not. The antiviral-induced decrease in Aβ is attributable to the reduced number of new viruses, and hence the reduction in viral spread. Since antiviral agents reduce greatly Aβ and P-tau accumulation in HSV1-infected cells, they would be suitable for treating AD with great advantage unlike current AD therapies, only the virus, not the host cell, would be targeted

Association between IgM Anti-Herpes Simplex Virus and Plasma Amyloid-Beta Levels

OBJECTIVE: Herpes simplex virus (HSV) reactivation has been identified as a possible risk factor for Alzheimer's disease (AD) and plasma amyloid-beta (Aβ) levels might be considered as possible biomarkers of the risk of AD. The aim of our study was to investigate the association between anti-HSV antibodies and plasma Aβ levels. METHODS: The study sample consisted of 1222 subjects (73.9 y in mean) from the Three-City cohort. IgM and IgG anti-HSV antibodies were quantified using an ELISA kit, and plasma levels of Aβ(1-40) and Aβ(1-42) were measured using an xMAP-based assay technology. Cross-sectional analyses of the associations between anti-HSV antibodies and plasma Aβ levels were performed by multi-linear regression. RESULTS: After adjustment for study center, age, sex, education, and apolipoprotein E-e4 polymorphism, plasma Aβ(1-42) and Aβ(1-40) levels were specifically inversely associated with anti-HSV IgM levels (β = -20.7, P=0.001 and β = -92.4, P=0.007, respectively). In a sub-sample with information on CLU- and CR1-linked SNPs genotyping (n=754), additional adjustment for CR1 or CLU markers did not modify these associations (adjustment for CR1 rs6656401, β = -25.6, P=0.002 for Aβ(1-42) and β = -132.7, P=0.002 for Aβ(1-40;) adjustment for CLU rs2279590, β = -25.6, P=0.002 for Aβ(1-42) and β = -134.8, P=0.002 for Aβ(1-40)). No association between the plasma Aβ(1-42)-to-Aβ(1-40) ratio and anti-HSV IgM or IgG were evidenced. CONCLUSION: High anti-HSV IgM levels, markers of HSV reactivation, are associated with lower plasma Aβ(1-40) and Aβ(1-42) levels, which suggest a possible involvement of the virus in the alterations of the APP processing and potentially in the pathogenesis of AD in human

Activation of PKR Causes Amyloid ß-Peptide Accumulation via De-Repression of BACE1 Expression

BACE1 is a key enzyme involved in the production of amyloid ß-peptide (Aß) in Alzheimer's disease (AD) brains. Normally, its expression is constitutively inhibited due to the presence of the 5′untranslated region (5′UTR) in the BACE1 promoter. BACE1 expression is activated by phosphorylation of the eukaryotic initiation factor (eIF)2-alpha, which reverses the inhibitory effect exerted by BACE1 5′UTR. There are four kinases associated with different types of stress that could phosphorylate eIF2-alpha. Here we focus on the double-stranded (ds) RNA-activated protein kinase (PKR). PKR is activated during viral infection, including that of herpes simplex virus type 1 (HSV1), a virus suggested to be implicated in the development of AD, acting when present in brains of carriers of the type 4 allele of the apolipoprotein E gene. HSV1 is a dsDNA virus but it has genes on both strands of the genome, and from these genes complementary RNA molecules are transcribed. These could activate BACE1 expression by the PKR pathway. Here we demonstrate in HSV1-infected neuroblastoma cells, and in peripheral nervous tissue from HSV1-infected mice, that HSV1 activates PKR. Cloning BACE1 5′UTR upstream of a luciferase (luc) gene confirmed its inhibitory effect, which can be prevented by salubrinal, an inhibitor of the eIF2-alpha phosphatase PP1c. Treatment with the dsRNA analog poly (I∶C) mimicked the stimulatory effect exerted by salubrinal over BACE1 translation in the 5′UTR-luc construct and increased Aß production in HEK-APPsw cells. Summarizing, our data suggest that PKR activated in brain by HSV1 could play an important role in the development of AD

Extracellular Matrix Heterogeneity Regulates Three-Dimensional Morphologies of Breast Adenocarcinoma Cell Invasion

Plasticity and reciprocity of breast cancer cells to various extracellular matrice (ECMs) are three-dimensionally analyzed in quantitative way in a novel and powerful microfluidic in vitro platform. This successfully demonstrates the metastatic potential of cancer cells and their effective strategies of ECM proteolytic remodeling and morphological change, while interacting with other cells and invading into heterogeneous ECMs.International Research & Development Program (Grant 2009-00631)National Research Foundation of Korea (Basic Science Research Program Grant 2012-022481

Geldanamycin-induced osteosarcoma cell death is associated with hyperacetylation and loss of mitochondrial pool of heat shock protein 60 (hsp60)

Osteosarcoma is one of the most malignant tumors of childhood and adolescence that is often resistant to standard chemo- and radio-therapy. Geldanamycin and geldanamycin analogs have been recently studied as potential anticancer agents for osteosarcoma treatment. Here, for the first time, we have presented novel anticancer mechanisms of geldanamycin biological activity. Moreover, we demonstrated an association between the effects of geldanamycin on the major heat shock proteins (HSPs) and the overall survival of highly metastatic human osteosarcoma 143B cells. We demonstrated that the treatment of 143B cells with geldanamycin caused a subsequent upregulation of cytoplasmic Hsp90 and Hsp70 whose activity is at least partly responsible for cancer development and drug resistance. On the other hand, geldanamycin induced upregulation of Hsp60 gene expression, and a simultaneous loss of hyperacetylated Hsp60 mitochondrial protein pool resulting in decreased viability and augmented cancer cell death. Hyperacetylation of Hsp60 seems to be associated with anticancer activity of geldanamycin. In light of the fact that mitochondrial dysfunction plays a critical role in the apoptotic signaling pathway, the presented data may support a hypothesis that Hsp60 can be another functional part of mitochondria-related acetylome being a potential target for developing novel anticancer strategies

Continuous reactive crystallization of pharmaceuticals using impinging jet mixers

For reactive crystallization of pharmaceuticals that show a rapid reaction rate, low solubility of active pharmaceutical ingredient and hence a large supersaturation, it was found in a recent study that a process design which integrates an impinging jet mixer and batch stirred tank produces high quality crystals. The current investigation examines if the short processing time of reactive crystallization permits the impinging jet mixer—stirred tank design to be modified to operate in a continuous mode. The new design combines an impinging jet mixer for feed introduction and reaction with a continuous stirred tank reactor (CSTR) and tubular reactor for crystal growth. A study of reactive crystallization of sodium cefuroxime (an antibiotic), using first a 1L CSTR then scaling to a 50L CSTR, found that the new design produces crystals of higher crystallinity, narrower particle size, and improved product stability, than batch crystallizers

Mechanical Stress Inference for Two Dimensional Cell Arrays

Many morphogenetic processes involve mechanical rearrangement of epithelial tissues that is driven by precisely regulated cytoskeletal forces and cell adhesion. The mechanical state of the cell and intercellular adhesion are not only the targets of regulation, but are themselves likely signals that coordinate developmental process. Yet, because it is difficult to directly measure mechanical stress {\it in vivo} on sub-cellular scale, little is understood about the role of mechanics of development. Here we present an alternative approach which takes advantage of the recent progress in live imaging of morphogenetic processes and uses computational analysis of high resolution images of epithelial tissues to infer relative magnitude of forces acting within and between cells. We model intracellular stress in terms of bulk pressure and interfacial tension, allowing these parameters to vary from cell to cell and from interface to interface. Assuming that epithelial cell layers are close to mechanical equilibrium, we use the observed geometry of the two dimensional cell array to infer interfacial tensions and intracellular pressures. Here we present the mathematical formulation of the proposed Mechanical Inverse method and apply it to the analysis of epithelial cell layers observed at the onset of ventral furrow formation in the {\it Drosophila} embryo and in the process of hair-cell determination in the avian cochlea. The analysis reveals mechanical anisotropy in the former process and mechanical heterogeneity, correlated with cell differentiation, in the latter process. The method opens a way for quantitative and detailed experimental tests of models of cell and tissue mechanics

The Pseudomonas aeruginosa PSL Polysaccharide Is a Social but Noncheatable Trait in Biofilms

Extracellular polysaccharides are compounds secreted by microorganisms into the surrounding environment, and they are important for surface attachment and maintaining structural integrity within biofilms. The social nature of many extracellular polysaccharides remains unclear, and it has been suggested that they could function as either cooperative public goods or as traits that provide a competitive advantage. Here, we empirically tested the cooperative nature of the PSL polysaccharide, which is crucial for the formation of biofilms in Pseudomonas aeruginosa. We show that (i) PSL is not metabolically costly to produce; (ii) PSL provides population-level benefits in biofilms, for both growth and antibiotic tolerance; (iii) the benefits of PSL production are social and are shared with other cells; (iv) the benefits of PSL production appear to be preferentially directed toward cells which produce PSL; (v) cells which do not produce PSL are unable to successfully exploit cells which produce PSL. Taken together, this suggests that PSL is a social but relatively nonexploitable trait and that growth within biofilms selects for PSL-producing strains, even when multiple strains are on a patch (low relatedness at the patch level). IMPORTANCE: Many studies have shown that bacterial traits, such as siderophores and quorum sensing, are social in nature. This has led to an impression that secreted traits act as public goods, which are costly to produce but benefit both the producing cell and its surrounding neighbors. Theories and subsequent experiments have shown that such traits are exploitable by asocial cheats, but we show here that this does not always hold true. We demonstrate that the Pseudomonas aeruginosa exopolysaccharide PSL provides social benefits to populations but that it is nonexploitable, because most of the fitness benefits accrue to PSL-producing cells. Our work builds on an increasing body of work showing that secreted traits can have both private and public benefits to cells

The Role of TLR4 in the Paclitaxel Effects on Neuronal Growth In Vitro

Paclitaxel (Pac) is an antitumor agent that is widely used for treatment of solid cancers. While being effective as a chemotherapeutic agent, Pac in high doses is neurotoxic, specifically targeting sensory innervations. In view of these toxic effects associated with conventional chemotherapy, decreasing the dose of Pac has been recently suggested as an alternative approach, which might limit neurotoxicity and immunosuppression. However, it remains unclear if low doses of Pac retain its neurotoxic properties or might exhibit unusual effects on neuronal cells. The goal of this study was to analyze the concentration-dependent effect of Pac on isolated and cultured DRG neuronal cells from wild-type and TLR4 knockout mice. Three different morphological parameters were analyzed: the number of neurons which developed neurites, the number of neurites per cell and the total length of neurites per cell. Our data demonstrate that low concentrations of Pac (0.1 nM and 0.5 nM) do not influence the neuronal growth in cultures in both wild type and TLR4 knockout mice. Higher concentrations of Pac (1-100 nM) had a significant effect on DRG neurons from wild type mice, affecting the number of neurons which developed neurites, number of neurites per cell, and the length of neurites. In DRG from TLR4 knockout mice high concentrations of Pac showed a similar effect on the number of neurons which developed neurites and the length of neurites. At the same time, the number of neurites per cell, indicating the process of growth cone initiation, was not affected by high concentrations of Pac. Thus, our data showed that Pac in high concentrations has a significant damaging effect on axonal growth and that this effect is partially mediated through TLR4 pathways. Low doses of Pac are devoid of neuronal toxicity and thus can be safely used in a chemomodulation mode. © 2013 Ustinova et al

Income and education as predictors of return to working life among younger stroke patients

<p>Abstract</p> <p>Background</p> <p>Socioeconomic conditions are not only related to poor health outcomes, they also contribute to the chances of recovery from stroke. This study examines whether income and education were predictors of return to work after a first stroke among persons aged 40-59.</p> <p>Methods</p> <p>All first-stroke survivors aged 40-59 who were discharged from a hospital in 1996-2000 and who had received income from work during the year prior to the stroke were sampled from the Swedish national register of in-patient care (n = 7,081). Income and education variables were included in hazard regressions, modelling the probability of returning to work from one to four years after discharge. Adjustments for age, sex, stroke subtype, and length of in-patient care were included in the models.</p> <p>Results</p> <p>Both higher income and higher education were associated with higher probability of returning to work. While the association between education and return to work was attenuated by income, individuals with university education were 13 percent more likely to return than those who had completed only compulsory education, and individuals in the highest income quartile were about twice as likely to return as those in the lowest. The association between socioeconomic position and return to work was similar for different stroke subtypes. Income differences between men and women also accounted for women's lower probability of returning to work.</p> <p>Conclusions</p> <p>The study demonstrates that education and income were independent predictors of returning to work among stroke patients during the first post-stroke years. Taking the relative risk of return to work among those in the higher socioeconomic positions as the benchmark, there may be considerable room for improvement among patients in lower socioeconomic strata.</p