A novel crosslinking protocol stabilizes amyloid β oligomers capable of inducing Alzheimer's-associated pathologies.
Erika N ClineArighno DasMaíra Assunção BiccaSaad N MohammadLuis F SchachnerJosette M KamelNadia DiNunnoAnthea WengJacob D PaschallRiana Lo BuFaraz M KhanMadeline G RollinsAshley N IvesGajendra ShekhawatNilson Nunes-TavaresFernando G de MelloPhilip D ComptonNeil L KelleherWilliam L KleinPublished in: Journal of neurochemistry (2019)
Amyloid β oligomers (AβOs) accumulate early in Alzheimer's disease (AD) and experimentally cause memory dysfunction and the major pathologies associated with AD, for example, tau abnormalities, synapse loss, oxidative damage, and cognitive dysfunction. In order to develop the most effective AβO-targeting diagnostics and therapeutics, the AβO structures contributing to AD-associated toxicity must be elucidated. Here, we investigate the structural properties and pathogenic relevance of AβOs stabilized by the bifunctional crosslinker 1,5-difluoro-2,4-dinitrobenzene (DFDNB). We find that DFDNB stabilizes synthetic Aβ in a soluble oligomeric conformation. With DFDNB, solutions of Aβ that would otherwise convert to large aggregates instead yield solutions of stable AβOs, predominantly in the 50-300 kDa range, that are maintained for at least 12 days at 37°C. Structures were determined by biochemical and native top-down mass spectrometry analyses. Assayed in neuronal cultures and i.c.v.-injected mice, the DFDNB-stabilized AβOs were found to induce tau hyperphosphorylation, inhibit choline acetyltransferase, and provoke neuroinflammation. Most interestingly, DFDNB crosslinking was found to stabilize an AβO conformation particularly potent in inducing memory dysfunction in mice. Taken together, these data support the utility of DFDNB crosslinking as a tool for stabilizing pathogenic AβOs in structure-function studies.
Keyphrases
- mass spectrometry
- oxidative stress
- high resolution
- high fat diet induced
- working memory
- cognitive decline
- randomized controlled trial
- traumatic brain injury
- molecular dynamics simulations
- type diabetes
- crystal structure
- small molecule
- liquid chromatography
- cognitive impairment
- machine learning
- cerebral ischemia
- highly efficient
- big data
- high performance liquid chromatography
- heat shock protein
- drug delivery
- case control
- deep learning
- inflammatory response
- wild type
- brain injury
- mild cognitive impairment
- subarachnoid hemorrhage