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Oxidative stress and mitochondrial dysfunction play an important role in the onset of neurodegenerative diseases; thus, the antioxidant use could be a promising preventive or therapeutic intervention. The food and agricultural industries generate huge quantities of by-products rich in biophenolic compounds. If, on the one hand, they represent a serious environmental problem, on the other hand, are valuable natural sources of antioxidants. In the present work, the total phenolic content and the antioxidant power of the wastewater derived from the production of four Sicilian extra virgin olive oils are shown. Four biophenols, hydroxytyrosol and tyrosol alcohols and caffeic acid (CA) and p-coumaric acids, were identified and quantified and their antioxidant ability determined. Their effects in counteracting Abeta(1-42) oligomer oxidative damage in LAN5 cell culture were investigated. Results indicated that CA was the most effective compound in counteracting the cell damages induced by Abeta(1-42) oligomers. RESUMENEl estres oxidativo y la disfuncion mitocondrial juegan un rol importante en el comienzo de ciertas enfermedades neurodegenerativas; en estos casos, el uso de antioxidantes puede ser una intervencion preventiva o terapeutica prometedora. Las industrias alimentarias y agricolas producen enormes cantidades de subproductos ricos en compuestos biofenolicos. Si bien por un lado representan un grave problema ambiental, por el otro constituyen valiosas fuentes naturales de antioxidantes. En el presente estudio se analizan el contenido fenolico total y el poder antioxidante de las aguas residuales (WW) derivadas de la produccion de cuatro aceites de oliva virgen extra (AOVE) de Sicilia. Para el efecto, Se identificaron y cuantificaron cuatro biofenoles, alcoholes hidroxitirosol (HT) y tirosol (TY), ademas de acidos cafeico (CA) y p-cumarico (CU), y se determino su capacidad antioxidante. Asimismo, se investigaron sus efectos para contrarrestar el dano oxidativo provocado por el oligomero Abeta(1-42) en cultivos celulares LAN5, constatandose que el CA fue el mas efectivo para contrarrestar el dano celular inducido por oligomeros Abeta(1-42).

BACKGROUND: Molecular chaperones are a very special class of proteins that play essential roles in many cellular processes like folding, targeting and transport of proteins. Moreover, recent evidence indicates that chaperones can act as potentially strong suppressor agents in Alzheimer's disease (AD). Indeed, in vitro experiments demonstrate that several chaperones are able to significantly slow down or suppress aggregation of Aβ peptide and in vivo studies reveal that treatment with specific chaperones or their overexpression can ameliorate some distinct pathological signs characterizing AD. METHODS: Here we investigate using a biophysical approach (fluorescence, circular dichroism (CD), transmission electron (TEM) and atomic force (AFM) microscopy, size exclusion chromatography (SEC)) the effect of the human chaperonin Hsp60 on Aβ fibrillogenesis. RESULTS: We found that Hsp60 powerfully inhibits Aβ amyloid aggregation, by closing molecular pathways leading to peptide fibrillogenesis. CONCLUSIONS: We observe that Hsp60 inhibits Aβ aggregation through a more complex mechanism than a simple folding chaperone action. The action is specifically directed toward the early oligomeric species behaving as aggregation seeds for on-pathway amyloid fibrillogenesis. GENERAL SIGNIFICANCE: Understanding the specificity of the molecular interactions of Hsp60 with amyloid Aβ peptide allowed us to emphasize the important aspects to be taken into consideration when considering the recent promising therapeutic strategies for neurodegeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

Liposomes are shell nanoparticles able to embed hydrophobic molecules into their lipid layers to be released to cells. In pharmaceutical sciences, liposomes remain the delivery system with the highest biocompatibility, stability, loading characteristics, tunable physicochemical properties. Squalene is a natural, water insoluble, lipid, abundant in olive oil and shark liver. Studies in vitro and in animal models suggest protective and inhibitory effects of squalene against cancer. To study its effect on cells, and to overcome its insolubility in water, we have designed and produced large unilamellar liposomes containing different quantities of this terpene (0%, 2.8%, 5% w/w). Liposomes have been characterized by different biophysical techniques. Size-exclusion and affinity chromatography showed a unimodal size distribution and confirmed the squalene loaded dose. Laurdan fluorescence evidenced the changes in the hydration of the external layer of liposomes as a function of squalene concentration. Dynamic light scattering and small angle X-ray scattering revealed squalene induced structural differences in the hydrodynamic radius distribution and in the bilayer thickness respectively. Finally, preliminary experiments on the effects of liposome-delivered squalene on tumor and non-tumor cell lines showed time- and dose-dependent cytotoxic effects on LAN5 tumor cells and no effect on NIH-3T3 normal cells.

When compared with other edible vegetable oils, the extra virgin olive oil (EVOO) exhibits excellent nutritional properties due to the presence of biophenolic compounds. Although they constitute only a very small amount of the unsaponifiable fraction of EVOO, biophenols strongly contribute to the sensorial properties of this precious food conferring it, for example, the bitter or pungent taste. Furthermore, it has been found that biophenols possess beneficial effects against many human pathologies such as oxidative stress, inflammation, cardiovascular diseases, cancer and aging-related illness. In the present work, the biophenolic content of 51 Italian and Spanish EVOOs was qualitatively and quantitatively identified and their antioxidant ability analyzed by oxygen radical absorbance capacity (ORAC) assay. Results indicated that the maximum relationship can be found if the ORAC value is correlated with the concentration of the large family composed by ligstroside and oleuropein derivatives together with their degradation products, hydroxytyrosol and tyrosol. Then, selected biophenolic extracts were tested in NIH-3T3 cell line to verify their ability in the recovery of the oxidative stress revealed by DCFH-DA assay. Results were linearly correlated with the concentration of ligstroside aglycone (aldehyde and hydroxyl form).

International audience; Curcumin is a natural polyphenol able to bind the amyloid beta peptide, which is related to Alzheimer's disease, and modify its self-assembly pathway. This paper focuses on a multi-disciplinary study that starts from the design of curcumin-like compounds with the key chemical features required for inhibiting amyloid beta aggregation, and reports the effects of these compounds on the in vitro aggregation of amyloid beta peptides. Chemoinformatic screening was performed through the calculation of molecular descriptors that were able to highlight the drug-like profile, followed by docking studies with an amyloid beta peptide fibril. The computational design underlined two different scaffolds that were easily synthesized in good yields. In vitro experiments, ranging from fluorescence spectroscopy and confocal microscopy up to small angle X-ray scattering, provided evidence that the synthesized compounds are able to modify the aggregation pattern of amyloid beta peptides both in the secondary structures, and in terms of the overall structure dimensions. The cytotoxic potential of the synthesized compounds was finally tested in vitro with a model neuronal cell line (LAN5). The overall view of this study suggests new concepts and potential difficulties in the design of novel drugs against diverse amyloidoses, including Alzheimer's disease

A simple method for the simultaneous determination of caffeine and chlorogenic acids content in green coffee was reported. The method was based on the use of UV/Vis absorption. It is relevant that the quantification of both caffeine and chlorogenic acids was performed without their preliminary chemical separation despite their spectral overlap in the range 250–350 nm. Green coffee was extracted with 70% ethanol aqueous solution; then the solution was analyzed by spectroscopy. Quantitative determination was obtained analytically through deconvolution of the absorption spectrum and by applying the Lambert-Beer law. The bands used for the deconvolution were the absorption bands of both caffeine and chlorogenic acids standards. The molar extinction coefficients for caffeine and chlorogenic acid in ethanol solution at 70% were calculated by using the chemical standards; the estimated values wereε(272 nm)=12159±97 M−1 cm−1for caffeine andε(330 nm)=27025±190 M−1 cm−1for chlorogenic acids molecules, respectively. The estimate of concentration values was in agreement with the one obtained by High Performance Liquid Chromatography quantification. The method is fast and simple and allows us to realize routine controls during the coffee production. In addition, it could be applied on roasted coffee and espresso coffee.

In the large class of molecules that maintain protein homeostasis, called molecular chaperones, chaperonins constitute a subclass that specifically assist the correct folding of newly synthesized proteins. Among them, Hsp60 is composed of a double heptameric ring structure with a large central cavity where the unfolded protein binds via hydrophobic interactions and is supported, in this function, by the co-chaperonin Hsp10. Hsp60 is typically located in the mitochondria, but in some pathological situations, such as cancers and chronic inflammatory diseases, Hsp60 accumulates in the cytoplasm. In these cases, cytoplasmatic Hsp60 is a mixture of mitochondrial Hsp60 secreted from mitochondria upon stress, and its precursor, called naive Hsp60, never entered into the organella. The difference between the naive and mitochondrial Hsp60s resides in the absence of the mitochondrial import signal (MIS) in the mitochondrial form, but information on their different structure and stability is still lacking. We present here a study on the stability against a chemical denaturant, of the different cytoplasmic Hsp60 species. By combining Circular Dichroism and Small Angle X-ray Scattering as experimental biophysical techniques to investigate Hsp60, we find that naive and mitochondrial Hsp60 (mtHsp60) forms differ in their stability. Furthermore, specific responses from the two forms are discussed in terms of the biological environment they are working in, thus opening new questions on their biological function.

Molecular chaperones are a class of proteins able to prevent non-specific aggregation of mitochondrial proteins and to promote their proper folding. Among them, human Hsp60 is currently considered as a ubiquitous molecule with multiple roles both in maintaining health conditions and as a trigger of several diseases. Of particular interest is its role in neurodegenerative disorders since it is able to inhibit the formation of amyloid fibrils.Hsp60 structure was considered, until recent years, analogue to the one of its bacterial homolog GroEL, one of the most investigated chaperones, whose crystallographic structure is a homo-tetradecamer, made up of two seven member rings. On the contrary, it has been recently demonstrated by some of us that Hsp60 shows an equilibrium of tetradecamers and heptamers in solution.We present the results of combined investigations including complementary approaches such as molecular dynamics (MD), circular dichroism (CD) and small-angle X-ray scattering (SAXS) concerning structure, self-organization, and stability of naive Hsp60 in solution in comparison with bacterial GroEL. We analyzed the structural differences between the two proteins in solution, evidencing their different oligomeric equilibria, too. Experiments at increasing concentrations of guanidinium hydrochloride provided further information on the stability of the oligomeric species, on the dissociation of tetradecamers into heptamers and monomers, until the unfolding. The unfolding free energy was obtained, proving that GroEL is more stable in respect to Hsp60.