Decrease in p3-Alcb37 and p3-Alcb40, products of Alcadein b generated by g-secretase cleavages, in aged monkeys and patients with Alzheimer’s disease

Introduction Neuronal p3-Alcβ peptides are generated from the precursor protein Alcadein β (Alcβ) through cleavage by α- and γ-secretases of the amyloid β (Aβ) protein precursor (APP). To reveal whether p3-Alcβ is involved in Alzheimer\u27s disease (AD) contributes for the development of novel therapy and/or drug targets. Methods We developed new sandwich enzyme-linked immunosorbent assay (sELISA) systems to quantitate levels of p3-Alcβ in the cerebrospinal fluid (CSF). Results In monkeys, CSF p3-Alcβ decreases with age, and the aging is also accompanied by decreased brain expression of Alcβ. In humans, CSF p3-Alcβ levels decrease to a greater extent in those with AD than in age-matched controls. Subjects carrying presenilin gene mutations show a significantly lower CSF p3-Alcβ level. A cell study with an inverse modulator of γ-secretase remarkably reduces the generation of p3-Alcβ37 while increasing the production of Aβ42. Discussion Aging decreases the generation of p3-Alcβ, and further significant decrease of p3-Alcβ caused by aberrant γ-secretase activity may accelerate pathogenesis in AD

Decrease in p3-Alcb37 and p3-Alcb40, products of Alcadein b generated by g-secretase cleavages, in aged monkeys and patients with Alzheimer’s disease

Introduction Neuronal p3-Alcβ peptides are generated from the precursor protein Alcadein β (Alcβ) through cleavage by α- and γ-secretases of the amyloid β (Aβ) protein precursor (APP). To reveal whether p3-Alcβ is involved in Alzheimer\u27s disease (AD) contributes for the development of novel therapy and/or drug targets. Methods We developed new sandwich enzyme-linked immunosorbent assay (sELISA) systems to quantitate levels of p3-Alcβ in the cerebrospinal fluid (CSF). Results In monkeys, CSF p3-Alcβ decreases with age, and the aging is also accompanied by decreased brain expression of Alcβ. In humans, CSF p3-Alcβ levels decrease to a greater extent in those with AD than in age-matched controls. Subjects carrying presenilin gene mutations show a significantly lower CSF p3-Alcβ level. A cell study with an inverse modulator of γ-secretase remarkably reduces the generation of p3-Alcβ37 while increasing the production of Aβ42. Discussion Aging decreases the generation of p3-Alcβ, and further significant decrease of p3-Alcβ caused by aberrant γ-secretase activity may accelerate pathogenesis in AD

Alkylated alkali lignin for compatibilizing agents of carbon fiber reinforced plastics with polypropylene

金沢大学理工研究域生命理工学系As an alternative to petroleum-based compatibilizing agents, we developed lignin derivatives for compatibilizing agents of carbon fiber-reinforced plastics that have thermoplasticity. In this study, alkyl chains were introduced into alkali lignin at various ratios to optimize the compatibility of the lignin derivatives with both polypropylene and carbon fiber. The interfacial shear strength between the two materials was improved from 8.2 to 17.2 MPa by mixing with the optimized lignin derivative. The value is comparable to that achieved with a typical petroleum-based compatibilizing agent (18.3 MPa).Embargo Period 6 monthsThis paper has supplementary information

Alternative Selection of beta-Site APP-Cleaving Enzyme 1 (BACE1) Cleavage Sites in Amyloid beta-Protein Precursor (APP) Harboring Protective and Pathogenic Mutations within the A beta Sequence

beta-Site APP-cleaving enzyme 1 (BACE1) cleaves amyloid -protein precursor (APP) at the bond between Met(671) and Asp(672) (-site) to generate the carboxyl-terminal fragment (CTF/C99). BACE1 also cleaves APP at another bond between Thr(681) and Gln(682) (-site), yielding CTF/C89. Cleavage of CTF/C99 by -secretase generates A(1-XX), whereas cleavage of CTF/C89 generates A(11-XX). Thus, -site cleavage by BACE1 is amyloidolytic rather than amyloidogenic. cleavage of mouse APP is more common than the corresponding cleavage of human APP. We found that the H684R substitution within human A, which replaces the histidine in the human protein with the arginine found at the corresponding position in mouse, facilitated cleavage irrespective of the species origin of BACE1, thereby significantly increasing the level of A(11-XX) and decreasing the level of A(1-XX). Thus, amino acid substitutions within the A sequence influenced the selectivity of alternative - or -site cleavage of APP by BACE1. In familial Alzheimer's disease (FAD), the APP gene harbors pathogenic variations such as the Swedish (K670N/M671L), Leuven (E682K), and A673V mutations, all of which decrease A(11-40) generation, whereas the protective Icelandic mutation (A673T) increases generation of A(11-40). Thus, A673T promotes cleavage of APP and protects subjects against AD. In addition, CTF/C99 was cleaved by excess BACE1 activity to generate CTF/C89, followed by A(11-40), even if APP harbored pathogenic mutations. The resultant A(11-40) was more metabolically labile in vivo than A(1-40). Our analysis suggests that some FAD mutations in APP are amyloidogenic and/or amyloidolytic via selection of alternative BACE1 cleavage sites

Molecular cytogenetic characterization of repetitive sequences comprising centromeric heterochromatin in three Anseriformes species.

The highly repetitive DNA sequence of centromeric heterochromatin is an effective molecular cytogenetic marker for investigating genomic compartmentalization between macrochromosomes and microchromosomes in birds. We isolated four repetitive sequence families of centromeric heterochromatin from three Anseriformes species, viz., domestic duck (Anas platyrhynchos, APL), bean goose (Anser fabalis, AFA), and whooper swan (Cygnus cygnus, CCY), and characterized the sequences by molecular cytogenetic approach. The 190-bp APL-HaeIII and 101-bp AFA-HinfI-S sequences were localized in almost all chromosomes of A. platyrhynchos and A. fabalis, respectively. However, the 192-bp AFA-HinfI-L and 290-bp CCY-ApaI sequences were distributed in almost all microchromosomes of A. fabalis and in approximately 10 microchromosomes of C. cygnus, respectively. APL-HaeIII, AFA-HinfI-L, and CCY-ApaI showed partial sequence homology with the chicken nuclear-membrane-associated (CNM) repeat families, which were localized primarily to the centromeric regions of microchromosomes in Galliformes, suggesting that ancestral sequences of the CNM repeat families are observed in the common ancestors of Anseriformes and Galliformes. These results collectively provide the possibility that homogenization of centromeric heterochromatin occurred between microchromosomes in Anseriformes and Galliformes; however, homogenization between macrochromosomes and microchromosomes also occurred in some centromeric repetitive sequences