Surface-bound basement membrane components accelerate amyloid-β peptide nucleation in air-free wells: An in vitro model of cerebral amyloid angiopathy

• Published in: Biochimica et biophysica acta Vol. 1834; no. 8; pp. 1624 - 1631
• Main Authors: Hasegawa, Kazuhiro, Ozawa, Daisaku, Ookoshi, Tadakazu, Naiki, Hironobu
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2013
• Subjects: agarose; agitation; air; amyloid; Amyloid - metabolism; Amyloid beta-Peptides - chemistry; Amyloid beta-Peptides - metabolism; Amyloid fibril; Amyloid β-peptide; arteries; Basement membrane; Basement Membrane - metabolism; Cerebral Amyloid Angiopathy; collagen; Collagen - metabolism; Collagen Type IV - metabolism; drainage; Drug Combinations; Extracellular Matrix - metabolism; fibrinogen; Fibrinogen - metabolism; fibronectins; Fibronectins - metabolism; Humans; In vitro fibril formation; In Vitro Techniques; laminin; Laminin - metabolism; Models, Molecular; Nucleation; Proteoglycans - metabolism; Succinimides - chemistry; surface proteins; ThT; CAA; AD; Nucleation; a.u; BM; ECM; Basement membrane; In vitro fibril formation; Aβ; LCSM; Cerebral amyloid angiopathy; AWI; HSA; NHS; Amyloid fibril; ISF; Amyloid β-peptide
• ISSN: 1570-9639; 0006-3002; 1878-1454
• DOI: 10.1016/j.bbapap.2013.04.011

Cerebral amyloid angiopathy is caused by deposition of the amyloid β-peptide which consists of mainly 39–40 residues to the cortical and leptomeningeal vessel walls. There are no definite in vitro systems to support the hypothesis that the vascular basement membrane may act as a scaffold of amyloid β-peptide carried by perivascular drainage flow and accelerate its amyloid fibril formation in vivo. We previously reported the critical roles of interfaces and agitation on the nucleation of amyloid fibrils at low concentrations of amyloid β-peptide monomers. Here, we reproduced the perivascular drainage flow in vitro by using N-hydroxysuccinimide-Sepharose 4 Fast flow beads as an inert stirrer in air-free wells rotated at 1rpm. We then reproduced the basement membranes in the media of cerebral arteries in vitro by conjugating Matrigel and other proteins on the surface of Sepharose beads. These beads were incubated with 5μM amyloid β(1–40) at 37°C without air, where amyloid β(1–40) alone does not form amyloid fibrils. Using the initiation time of fibril growth kinetics (i.e., the lag time of fibril growth during which nuclei, on-pathway oligomers and protofibrils are successively formed) as a parameter of the efficiency of biological molecules to induce amyloid fibril formation, we found that basement membrane components including Matrigel, laminin, fibronectin, collagen type IV and fibrinogen accelerate the initiation of amyloid β-peptide fibril growth in vitro. These data support the essential role of vascular basement membranes in the development of cerebral amyloid angiopathy. [Display omitted] •CAA is caused by amyloid β-peptide deposition to the brain vessel walls.•Surface-bound basement membrane components accelerate Aβ-peptide nucleation in vitro.•Vascular basement membranes play an essential role in the development of CAA.•A novel system for evaluating the efficiency of molecules to induce amyloid fibrils.