Several lines of evidence suggest that ß-amyloid (Aß) plays a central role in the pathogenesis of Alzheimer’s disease (AD). Soluble oligomers, rather than amyloid fibrils, are now thought to be the principal pathogenic form of Aß.
In collaboration with researchers in Japan (see Fukumoto et al. (2010) FASEB J. 24: 2716-2726) we have recently developed a novel immunoassay for high-molecular-weight (HMW) Aß oligomers and have detected significantly elevated levels of these oligomers in cerebrospinal fluid (CSF) samples from patients with AD or mild cognitive impairment (MCI), compared to controls. Furthermore, the levels of HMW oligomers showed a negative correlation with cognitive ability, as assessed by MMSE scores.
Thus, CSF HMW Aß oligomers could, potentially, be used as a biomarker for early detection of AD, and/or as a marker for tracking disease progression.
We have also developed a peptidomimetic (retro-inverso-peptide) inhibitor that blocks the formation of Aß oligomers in vitro and is particularly effective against the longer and more pathogenic Aß42 (see Taylor et al. (2010) Biochemistry 49: 3261–3272).
Development and implementation of approaches such as these, for the early detection and treatment of AD, will be essential for coping with the increasing numbers of dementia sufferers in ageing populations.
David Allsop, Professor of Neuroscience at Lancaster University, has a long-standing interest in the role of protein aggregation in neurodegenerative disease.
He started this line of research at the Queen’s Medical Centre, Nottingham, where he was the first person to isolate senile plaque amyloid from frozen post-mortem brains of patients with Alzheimer’s disease (AD) and the first to raise monoclonal antibodies to Aß. As a post-doctoral researcher, he subsequently worked with George Glenner (University of California, San Diego) and at The Tokyo Research Institute of Psychiatry.
He obtained his first academic position at The Queen’s University of Belfast, where he co-authored a highly cited review article which sets out the basis of the ‘amyloid cascade’ hypothesis (Hardy & Allsop (1991) Trends Pharmacol. Sci. 12: 383-388). He then moved to industry (with SmithKline Beecham) before accepting an academic position at Lancaster University.
His current research is focussed on detection of amyloidogenic proteins in body fluids as potential biomarkers, and on development of drugs to inhibit protein aggregation.
Other recent work has identified the generation of reactive oxygen species from aggregating proteins as a potential common mechanism of cell death in neurodegenerative disease.