As of today there is increasing evidence that accumulation of soluble oligomeric assemblies of β-amyloid polypeptide (Aβ) play a key role in Alzheimer’s Disease (AD) pathology. Specifically, 56 kDa oligomeric species were shown to be correlated with impaired cognitive function in AD mice model. It is assumed that the main damage arises from the Amyloid-beta fibrils plaque deposits in the brain, such as soluble oligomeric assemblies. Several reports have documented the inhibition of Aβ plaque formation by compounds from natural sources. Yet, evidence for the ability of common edible elements to modulate Aβ oligomerization remains an unmet challenge. In a research by Prof Michal Ovadia, at Tel Aviv University, in Israel, published in the Jan 2011 issue of PLOS One, a natural substance, based on cinnamon extract (CEppt), was identified. This extract was found tomarkedly inhibit the formation of toxic Aβ oligomers and prevents the toxicity of Aβ on neuronal PC12 cells.
When administered to an AD fly model, CEppt rectified their reduced longevity, fully recovered their locomotion defects and totally abolished tetrameric species of Aβ in their brain.
Furthermore, oral administration of CEppt to an aggressive AD transgenic mice model led to marked decrease in 56 kDa Aβ oligomers, reduction of plaques and improvement in cognitive behavior. The results present a novel prophylactic approach for inhibition of toxic oligomeric Aβ species formation in AD through the utilization of a compound that is currently in use in human diet.
According to another study: Cinnamon Extract Inhibits Tau Aggregation Associated with Alzheimer’s Disease In Vitro” published in the July 2009 issue of the Journal of Alzheimer’s Disease, an aqueous extract of Ceylon cinnamon (C. zeylanicum) is found to inhibit tau aggregation and filament formation, hallmarks of Alzheimer’s disease (AD). The extract can also promote complete disassembly of recombinant tau filaments and cause substantial alteration of the morphology of paired-helical filaments isolated from AD brain. Cinnamon extract (CE) was not deleterious to the normal cellular function of tau, namely the assembly of free tubulin into microtubules. An A-linked proanthocyanidin trimer molecule was purified from the extract and shown to contain a significant proportion of the inhibitory activity. Treatment with polyvinylpyrolidone effectively depleted all proanthocyanidins from the extract solution and removed the majority, but not all, of the inhibitory activity. The remainder inhibitory activity could be attributed to cinnamaldehyde. This research shows that compounds endogenous to cinnamon may be beneficial to AD themselves or may guide the discovery of other potential therapeutics if their mechanisms of action can be discerned.