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It has been established that Hsp60 can accumulate in the cytosol in various pathological conditions, including cancer and chronic inflammatory diseases. Part or all of the cytosolic Hsp60 could be naïve, namely, bear the mitochondrial import signal (MIS), but neither the structure nor the in solution oligomeric organization of this cytosolic molecule has still been elucidated. Here we present a detailed study of the structure and self-organization of naïve cytosolic Hsp60 in solution. Results were obtained by different biophysical methods (light and X ray scattering, single molecule spectroscopy and hydrodynamics) that all together allowed us to assay a wide range of concentrations of Hsp60. We found that Naïve Hsp60 in aqueous solution is assembled in very stable heptamers and tetradecamers at all concentrations assayed, without any trace of monomer presence.

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

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Neuroserpin, a member of the serpin protein superfamily, is an inhibitor of proteolytic activity that is involved in pathologies such as ischemia, Alzheimer's disease, and Familial Encephalopathy with Neuroserpin Inclusion Bodies (FENIB). The latter belongs to a class of conformational diseases, known as serpinopathies, which are related to the aberrant polymerization of serpin mutants. Neuroserpin is known to polymerize, even in its wild type form, under thermal stress. Here, we study the mechanism of neuroserpin polymerization over a wide range of temperatures by different techniques. Our experiments show how the onset of polymerization is dependent on the formation of an intermediate monomeric conformer, which then associates with a native monomer to yield a dimeric species. After the formation of small polymers, the aggregation proceeds via monomer addition as well as polymer-polymer association. No further secondary mechanism takes place up to very high temperatures, thus resulting in the formation of neuroserpin linear polymeric chains. Most interesting, the overall aggregation is tuned by the co-occurrence of monomer inactivation (i.e. the formation of latent neuroserpin) and by a mechanism of fragmentation. The polymerization kinetics exhibit a unique modulation of the average mass and size of polymers, which might suggest synchronization among the different processes involved. Thus, fragmentation would control and temper the aggregation process, instead of enhancing it, as typically observed (e.g.) for amyloid fibrillation.

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 were (272 nm) = 12159 ± 97 M −1 cm −1 for caffeine and (330 nm) = 27025 ± 190 M −1 cm −1 for 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.