No abstract

ABSTRACT

a b s t r a c tAmyloid-ß (Aß) fragments, oligomeric Aß aggregates, and pyroglutamylated-Aß peptides, as well as epigenetic mechanisms and autophagy dysfunction all appear to contribute in various ways to Alzheimer's disease progression. We previously showed that dietary supplementation of oleuropein aglycone, a natural phenol abundant in the extra virgin olive oil, can be protective by reducing Aß42 deposits in the brain of young and middle-aged TgCRND8 mice. Here, we extended our study to aged TgCRND8 mice showing increased pE3-Aß in the brain deposits. We report that oleuropein aglycone is active against glutaminylcyclase-catalyzed pE3-Aß generation reducing enzyme expression and interferes both with Aß42 and pE3-Aß aggregation. Moreover, the phenol astonishingly activates neuronal autophagy even in mice at advanced stage of pathology, where it increases histone 3 and 4 acetylation, which matches both a decrease of histone deacetylase 2 expression and a significant improvement of synaptic function. The occurrence of these functional, epigenetic, and histopathologic beneficial effects even at a late stage of the pathology suggests that the phenol could be beneficial at the therapeutic, in addition to the prevention, level.

1 The role of adenosine A 3 receptor activation during ischaemia-like conditions produced by oxygen and glucose deprivation (OGD) was evaluated with extracellular recordings from the CA1 region of rat hippocampal slices. In all, 7 min of OGD evoked tissue anoxic depolarisation (AD, peak at B7 min from OGD start, n ¼ 20) and were invariably followed by irreversible loss of electrically evoked field epsps (fepsps, n ¼ 42). 3 When tested on OGD episodes of longer duration (8-10 min, n ¼ 18), 100 nM MRS 1523 prevented or delayed the appearance of AD and exerted a protective effect on neurotransmission for episodes of up to 9 min duration. In the absence of AD, the fepsp recovery was almost total, regardless of OGD episode duration. 4 These findings support the notion that A 3 receptor stimulation is deleterious during ischaemia and suggest that selective A 3 receptor block may substantially increase the resistance of the CA1 hippocampal region to ischaemic damage.

We extracted, purified and characterized 8 sesquiterpene fractions from Commyphora molmol. In particular, we focused our attention on a mixture of furanodiene-6-one and methoxyfuranoguaia-9-ene-8-one, which showed antibacterial and antifungal activity against standard pathogenic strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, with minimum inhibitory concentrations ranging from 0.18 to 2.8 micrograms/ml. These compounds also had local anaesthetic activity, blocking the inward sodium current of excitable mammalian membranes.