Metal chelation, radical scavenging and inhibition of Aβ42 fibrillation by food constituents in relation to Alzheimer’s disease

Metal chelation, radical scavenging and inhibition of Aβ42 fibrillation by food constituents in relation to Alzheimer’s disease

Food Chemistry, November 2015

26775960

Stephen Chan, Srinivas Kantham, Venkatesan M. Rao, Manoj Kumar Palanivelu, Hoang L. Pham, P. Nicholas Shaw, Ross P. McGeary, Benjamin P. Ross

Various food constituents have been proposed as disease-modifying agents for Alzheimer's disease (AD), due to epidemiological evidence of their beneficial effects, and for their ability to ameliorate factors linked to AD pathogenesis, namely by: chelating iron, copper and zinc; scavenging reactive oxygen species; and suppressing the fibrillation of amyloid-beta peptide (Aβ). In this study, nine different food constituents (l-ascorbic acid, caffeic acid, caffeine, curcumin, (-)-epigallocatechin gallate (EGCG), gallic acid, propyl gallate, resveratrol, and α-tocopherol) were investigated for their effects on the above factors, using metal chelation assays, antioxidant assays, and assays of Aβ42 fibrillation. An assay method was developed using 5-Br-PAPS to examine the complexation of Zn(II) and Cu(II). EGCG, gallic acid, and curcumin were identified as a multifunctional compounds, however their poor brain uptake might limit their therapeutic effects. The antioxidants l-ascorbic acid and α-tocopherol, with better brain uptake, deserve further investigation for specifically addressing oxidative stress within the AD brain.