RETRACTION: Physiological Levels of Amyloid Peptides Stimulate the Angiogenic Response Through FGF-2.

BackgroundTargeted proteomics by selected reaction monitoring (SRM) with high signal‐noise ratio enables to quantify hundreds of proteins with high sensitivity. However, since the lowest number of proteins is less than 10 copies in a single cell, further improvement from the aspects of sensitivity is necessary to detect these ones.MethodsUnlike conventional particle‐packed columns used in liquid chromatography (LC), monolithic columns are characterized by an orderly 3D‐network structure [1]. With the monolithic columns, high‐performance separation with a thin skeleton and back pressure can be achieved. Further improvement in detection‐sensitivity is achieved by reducing column inner diameter (I.D.), because small elution volume concentrates analytes and efficient desolvation increases ionization efficiency. Hence, we developed meter‐long monolithic columns with small I.D. to SRM‐based proteomics and aimed to improve detection‐sensitivity of mass spectrometry (MS) to increase peak intensity in peptide levels. BSA tryptic digests were directly injected into monolithic columns with different length (500 mm or 1000 mm) and I.D. (100 μm or 75 μm), and peak capacity and peak area were evaluated.Results & DiscussionSeparation efficiency increased 1.9 times by lengthening a monolithic column from 500 mm to 1000 mm. Detection‐sensitivity increased 2.3 times in peptide level by reducing column I.D. from 100 μm to 75 μm. Furthermore, even when column I.D. was reduced, there were no differences in the coefficient of variation values of the peak area. These results showed reduction of I.D. of meter‐long monolithic columns increased detection‐sensitivity in SRM‐based proteomics [2].Support or Funding InformationThis work was supported by JST CREST (Grant Number JPMJCR16G2), Japan.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Statistical models for the analysis of protein expression changes by stable isotope labeling are still poorly developed, particularly for data obtained by 16O/18O labeling. Besides large scale test experiments to validate the null hypothesis are lacking. Although the study of mechanisms underlying biological actions promoted by vascular endothelial growth factor (VEGF) on endothelial cells is of considerable interest, quantitative proteomics studies on this subject are scarce and have been performed after exposing cells to the factor for long periods of time. In this work we present the largest quantitative proteomics study to date on the short term effects of VEGF on human umbilical vein endothelial cells by 18O/16O labeling. Current statistical models based on normality and variance homogeneity were found unsuitable to describe the null hypothesis in a large scale test experiment performed on these cells, producing false expression changes. A random effects model was developed including four different sources of variance at the spectrum-fitting, scan, peptide, and protein levels. With the new model the number of outliers at scan and peptide levels was negligible in three large scale experiments, and only one false protein expression change was observed in the test experiment among more than 1000 proteins. The new model allowed the detection of significant protein expression changes upon VEGF stimulation for 4 and 8 h. The consistency of the changes observed at 4 h was confirmed by a replica at a smaller scale and further validated by Western blot analysis of some proteins. Most of the observed changes have not been described previously and are consistent with a pattern of protein expression that dynamically changes over time following the evolution of the angiogenic response. With this statistical model the 18O labeling approach emerges as a very promising and robust alternative to perform quantitative proteomics studies at a depth of several thousand proteins.

IntroductionThe RAS and KKS have a role modulating obesity and consequently can contribute to development of associated diseases, such as, diabetes mellitus, dyslipidemia, hypertension and metabolic syndrome. Preliminary studies of our group showed a correlation between diminished levels of the vasodilator peptides, Ang 1–7 and BK, and increased body mass. Also, obese and morbid obese adolescents presented higher levels of Ang I and des‐Arg9BK, a pro‐inflammatory kinin.AimWe evaluated the enzymatic activity profile of proteases involved on the biosynthesis and inactivation of RAS and KKS peptides in children and adolescents.MethodsIt is a cross‐sectional study, including 360 children and adolescents aged from 6 to 19 years. The participants were categorized into four groups according to their BMI percentile; underweight (n = 57), normal weight (n= 120), overweight (n = 120) and obese (n = 63). The urines were concentrated 10‐fold and dialyzed with TRIS – HCl pH 8 buffer. The urinary activity of ACE, ACE2, NEP and Cathepsin D were assayed. ACE activity was assessed through fluorimetric assay using the substrate Z‐Phe‐His‐Leu. To the remaining enzymes, fluorescence‐quenching peptide substrates with specific sequence were used. Additionally, assessment of cardiovascular parameters, anthropometric measurements, lipids profile and biochemical parameters were performed.ResultsCathepsin D has reduced activity in the overweight group when compared to the normal weight group (0,027 μM/min/mg de creatinine vs 0,098 μM/min/mg de creatinine, p < 0,01). Waist‐height‐ratio was used to assess cardiovascular risk, cathepsin D activity was diminished in the high‐risk group in comparison to control (0,028 μM/min/mg de creatinine vs 0,095 μM/min/mg de creatinine, p <0,01). According to Spearman correlation test, cathepsin Dhas a moderate negative correlation with waist circumference (cm), waist‐to‐hip ratio, waist‐to‐height ratio, fat mass (Kg), percentage of fat (%) and IMC (Kg/m2). The ACE activity presents moderated positive correlation with VLDL‐C levels and negative correlation with HDL‐C.ConclusionIn physiological conditions it is improbable that impaired cathepsin D activity alone contributes significantly to the formation of RAS angiotensin I peptide. However, considering the clearance of cathepsin D as a mechanism to keep its levels within a narrow range in circulation, this data can support that cathepsin D accumulates in the blood of overweight and high cardiovascular risk children. In relation to the remaining enzymes evaluated, there were not differences statistically significant between the groups. However, they present different enzymatic profile and can contribute to differences on levels of RAS and KKS peptides. Therefore, further evaluation of cathepsin D expression in urine and blood, as well as, measurement of RAS and KKS peptides levels are necessary to effective conclusions.Support or Funding InformationCAPES and FAPESPThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Background. Alzheimer's disease (AD) is a multifactorial disease, and the mechanisms underlying its pathogenesis are complex. Several studies have implicated amyloid β (Aβ) accumulation, hyperphosphorylated tau, oxidative stress, metal dysregulation, mitochondrial dysfunction, and inflammatory response as major interconnecting networks leading to neuronal and synaptic degeneration. Aim. The present study was designed to evaluate the neuroprotective effects of cholecalciferol (vitamin D3) and rivastigmine, alone and in combination, on the progression of Alzheimer's disease induced by intracerebroventricular administration of streptozotocin and possible anti-inflammatory mechanisms of action. Materials and Methods. Adult male albino rats were divided randomly into five groups: group I acts as control. In group II (Alzheimer's group), Alzheimer's was induced by single bilateral intracerebroventricular injection of STZ (3mg/kg). Group III (cholecalciferol treated group) rats received cholecalciferol (42 IU/kg, s.c.) for 21 days immediately after ICV-STZ injection. Group IV (rivastigmine-treated group) Alzheimer's rats received rivastigmine (1.5 mg/kg, s.c.) for a period of 21 days immediately after ICV-STZ injection. Group V (rivastigmine + cholecalciferol) rats received rivastigmine plus cholecalciferol for 21 days immediately after ICV-STZ injection. Cognitive impairment was evaluated by Morris Water Maze test. Serum and brain pro-inflammatory mediators (TNF-α and IL-1β) were measured. Also, brain level of acetylcholine was measured. Moreover, serum and brain levels of amyloid beta peptide were evaluated. Results. After 21 days of induction of Alzheimer's, the ICV-STZ induced significant impairment of memory and declined cognition as manifested by the increased latency period in Morris Water Maze test. Serum and brain levels of TNF-α, IL-1β, and amyloid peptide were significantly increased. On the other hand, brain acetylcholine level was significantly decreased compared with the control group. All these parameters were significantly improved by rivastigmine alone and in combination with vitamin D3. These results clearly pointed to the pivotal role of rivastigmine and vitamin D3 in STZ induced Alzheimer's in rats by improving inflammatory status. Conclusion. The present study concludes the neuroprotective effect of rivastigmine and vitamin D3 in Alzheimer's disease rats by reducing inflammatory mediators (TNF-α and IL-1β) and amyloid β peptide and improving acetylcholine levels in brain.

Acknowledgements Contributors and editors biographical notes Literary philosophers: Introductory remarks Carolyn Korsmeyer Intersections: Philosophy and literature, or, why ethical criticism prefers realism Deborah Knight Philosophy and the philosophical, literate and the literary, Borges and the labyrinthine William Irwin Borges' monsters: Unnatural wholes and the transformation of genre Lois Parkinson Zamora Borges' 'Pierre Menard': Philosophy or literature? Jorge J.E. Gracia Borges: Mimesis and modernism Anthony Cascardi Philosophy and the revenge of literature: Calvino on comedy Elizabeth Millan-Zaibert The writing of the system: A tribute to Borges and Calvino Henry Sussman Knowledge, theories and entertainment in Eco's Labyrinths of intertextuality Rocco Capozzi Borges, Calvino, Eco: The philosophies of Metafiction Wladimir Krysinski Philosophy and literature in Calvion's Tales Ermanno Bencivenga Bibliography Indexes

Accumulation of tumor suppressor WWOX with Ser14 phosphorylation has been shown in growing solid tumors and brain lesions with Alzheimer's disease. Functional significance of this regard is unknown. A portion of cytosolic WWOX is recruited to the cell membrane/cytoskeleton by binding hyaluronidase Hyal‐2. Here, we identified a cell surface‐exposed N‐terminal epitope WWOX7‐21 (amino acid #7 to 21), which is in front of the first WW domain. Treatment of breast 4T1 cancer stem cell spheres with the WWOX7‐21 antibody resulted in dramatic inhibition of ceritinib‐mediated cell death (>85% inhibition). Similar results were observed using other therapeutic chemicals. In contrast, when 4T1 stem cell spheres were treated with micromolar levels of synthetic WWOX7‐21 and WWOX7‐11 peptides, 4T1 cells in the spheres became highly susceptible to death by ceritinib. Notably, when pS14‐WWOX7‐11 peptide was used to treat the 4T1 spheres, cells significantly acquired resistance to ceritinib. WWOX7‐21 and WWOX7‐11 peptides caused spleen Z cell expansion and activation by expressing Hyal‐2, Zfra, and Noxa to block 4T1 growth and metastasis in mice. Accordingly, stimulating membrane Hyal‐2 with agonist Hyal‐2 antibody, sonicated hyaluronan and Zfra peptide primed Z cells for activation and blocking cancer growth in vivo. Purified activated Z cells aggressively attacked and caused death of 4T1 stem cells in spheres in vitro, as determined by time‐lapse microscopy. In stark contrast, pSer14‐WWOX7‐21 peptide significantly induced clonal expansion of spleen CD8alpha+ T and CD19+ B cells in vivo and enhanced cancer growth. Together, phosphorylation at Ser14 turns WWOX from tumor suppressor into tumor promoter.Support or Funding InformationMOST, TaiwanThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Background and ObjectivesWe aim to explore blood plasma levels of matrix metalloproteinase‐9 (MMP9) in acute mild traumatic brain injury (mTBI), and test if MMP9 levels correlate with quantitative electroencephalography (qEEG) during working memory (WM) testing.MethodsStudy participants were recruited from the emergency department of Huntington Memorial Hospital in Pasadena, CA, consisting of thirteen acute mTBI civilian patients and seven controls who were trauma patients without head injury ranging between 18–50 years of age. Blood samples were collected from three time points: within 1 week, 14 days, and 30 days after the injury. To study blood‐brain‐barrier (BBB) integrity, we quantified three MMP9 peptides (SLGPALLLLQK, QLSLPETGELDSATLK, and LGLGADVAQVTGALR) using liquid chromatography and mass spectrometry with stable isotope standards. We also employed qEEG at each visit to investigate alpha frequency power during N‐back WM processing.Results & DiscussionWe detected the presence of all three MMP9 peptides in blood plasma. We observed that MMP9 peptide levels in both mTBI and controls were decreasing in abundance in the 2–4 weeks after injury compared to the first week. Importantly, the MMP9 levels of the LGLGADVAQVTGALR peptide but not the peptides from the pre‐protein, were significantly higher in the mTBI group 2–4 weeks after the injury, consistent with known “secondary injury” phenomena. MMP9 levels correlated with alpha power during WM testing, at the first visit for the controls but not for the mTBI patients, at specific brain regions during different WM load. Elevated MMP9 levels indicate the BBB integrity is compromised acutely after mTBI. The correlations between MMP9 and alpha power during WM that we only found in the trauma controls need further investigation.Support or Funding InformationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

A new decade, a new editor

Candidate genes for Alzheimer's disease are associated with individual differences in plasma levels of beta amyloid peptides in adults with Down syndrome

Microassay for the assessment of low levels of hydroxyproline.

Neuropeptides in hippocampus and cortex in transgenic mice overexpressing V717F β-amyloid precursor protein — initial observations

To date there are no conclusive reports on the usefulness of determining amyloid peptides in the serum of patients with Alzheimer's disease (AD). Only anecdotal works deal with the changes in the peptides produced by cholinesterase inhibitors. In this study, the authors investigated and studied the clinical significance of plasmatic Abeta-40 and Abeta-42 peptide levels in a series of 34 consecutive patients with AD. The baseline levels of the Abeta-40 peptide correlated negatively with the Mini Examen Cognoscitivo (Spanish version of the Mini-Mental test) score. Complete follow-up was possible in 22 patients. After 6 months of treatment with galantamine, the mean Abeta-40 peptide levels decreased from 31.86 to 24.22 pg/mL. The baseline levels of Abeta-40 were predictive of response to treatment in the Alzheimer's Disease Assessment Scale-Cognitive Subscale. The authors conclude that determining plasmatic Abeta-40 peptide levels could be useful in predicting and monitoring response to treatment in AD.

The levels of amyloid peptides in the brain are regulated by a clearance pathway from neurons to the blood-brain barrier. The first step is thought to involve diffusion from the plasma membrane to the interstitium. However, amyloid peptides are hydrophobic and avidly intercalate within membranes. The ABC transporter P-glycoprotein is implicated in the clearance of amyloid peptides across the blood-brain, but its role at neurons is undetermined. We here propose that P-glycoprotein mediates 'exit' of amyloid peptides from neurons. Indeed, amyloid peptides have physicochemical similarities to substrates of P-glycoprotein, but their larger size represents a conundrum. This review probes the plausibility of a mechanism for amyloid peptide transport by P-glycoprotein exploiting evolving biochemical and structural models.

Alzheimer's disease is characterized by amyloid peptide formation and deposition, neurofibrillary tangles, synaptic loss and central cholinergic dysfunction, dysfunction of energy metabolism, and dementia; however, the interactions between these hallmarks remain poorly defined. We studied a well characterized mouse model of amyloid deposition, the doubly transgenic APP(SWE)xPSEN1dE9 mouse. At 10 to 14 months of age, these mice had high levels of amyloid peptides (6.6 microg/g wet weight) and widespread amyloid plaques. Extracellular levels of acetylcholine (ACh) were determined by microdialysis in the hippocampus and were comparable with nontransgenic mice from the same colony. In the open field, both mouse strains responded with a 3-fold increase of hippocampal ACh release. Exploratory behavior of the transgenic mice appeared normal. Infusion of scopolamine evoked 5- to 6-fold increases of ACh levels in both mouse strains. High-affinity choline uptake and cholinesterase activities were identical in both mouse lines. Extracellular levels of glucose and glycerol were similar in control and transgenic mice, whereas lactate levels were slightly (p = 0.06) and glutamate levels significantly (p = 0.02) lower in transgenic mice. Exploration caused increases of glucose and lactate, whereas infusion of scopolamine (1 microM) increased glucose but not lactate. Glutamate levels were increased by scopolamine, whereas glycerol remained constant under all the conditions. We conclude that amyloid peptide production and plaque deposition causes minor changes in cholinergic function and energy metabolites in transgenic mice in vivo. Amyloid peptide formation and/or deposition may not be sufficient for long-term cholinergic or metabolic dysfunction.

In the brain of Alzheimer's disease (AD) patients, neurotoxic amyloid peptides accumulate and are deposited as senile plaques. A major therapeutic strategy aims to decrease production of amyloid peptides by inhibition of gamma-secretase. Presenilins are polytopic transmembrane proteins that are essential for gamma-secretase activity during development and in amyloid production. By loxP/Cre-recombinase-mediated deletion, we generated mice with postnatal, neuron-specific presenilin-1 (PS1) deficiency, denoted PS1(n-/-), that were viable and fertile, with normal brain morphology. In adult PS1(n-/-) mice, levels of endogenous brain amyloid peptides were strongly decreased, concomitant with accumulation of amyloid precursor protein (APP) C-terminal fragments. In the cross of APP[V717I]xPS1 (n-/-) double transgenic mice, the neuronal absence of PS1 effectively prevented amyloid pathology, even in mice that were 18 months old. This contrasted sharply with APP[V717I] single transgenic mice that all develop amyloid pathology at the age of 10-12 months. In APP[V717I]xPS1 (n-/-) mice, long-term potentiation (LTP) was practically rescued at the end of the 2 hr observation period, again contrasting sharply with the strongly impaired LTP in APP[V717I] mice. The findings demonstrate the critical involvement of amyloid peptides in defective LTP in APP transgenic mice. Although these data open perspectives for therapy of AD by gamma-secretase inhibition, the neuronal absence of PS1 failed to rescue the cognitive defect, assessed by the object recognition test, of the parent APP[V717I] transgenic mice. This points to potentially detrimental effects of accumulating APP C99 fragments and demands further study of the consequences of inhibition of gamma-secretase activity. In addition, our data highlight the complex functional relation of APP and PS1 to cognition and neuronal plasticity in adult and aging brain.