Intracellular accumulation and cytotoxicity of doxorubicin with different pharmaceutical formulations in human cancer cell lines

The structure of both carrier and anticancer drug affects the intracellular fate of a transported drug. The study investigated in vitro intracellular accumulation and cytotoxic activity of doxorubicin-loaded solid lipid nanoparticles (SLN), doxorubicin in pegylated liposomes (Caelyx) and free doxorubicin. Intracellular doxorubicin levels and cytotoxic activity were determined by high performance liquid chromatography with fluorescence detection, and by the trypan blue dye exclusion assay, respectively. Doxorubicin-loaded SLN inhibited cell growth more strongly than either free or liposomal doxorubicin, in human colorectal adenocarcinoma, HT-29, retinoblastoma Y79, and glioblastoma U373 cell lines. The IC50 values for doxorubicin-loaded SLN were significantly lower after 24 h exposure than those for free doxorubicin in all cell lines; after 48 h exposure they were lower than those for liposomal doxorubicin in HT-29 and Y79 cells. The enhanced cytotoxic activity of doxorubicin-loaded SLN was associated with increased drug incorporation in cells: intracellular doxorubicin levels were significantly enhanced after exposure to drug-loaded SLN versus either free or liposomal drug. Rate of intracellular accumulation and cytotoxic activity also differed among different cell lines; in particular, cells of epithelial origin were found to be more sensitive to doxorubicin-loaded SLN. In conclusion, the greater sensitivity of HT-29, Y79, and U373 cells to doxorubicin-loaded SLN than to the other drug formulations may be due to the capability of the delivery system to enhance drug action, through a marked uptake and accumulation of SLN within the cell.     

Convergent Effects of Resveratrol and PYK2 on Prostate Cells

Resveratrol, a dietary polyphenol, is under consideration as chemopreventive and chemotherapeutic agent for several diseases, including cancer. However, its mechanisms of action and its effects on non-tumor cells, fundamental to understand its real efficacy as chemopreventive agent, remain largely unknown. Proline-rich tyrosine kinase 2 (PYK2), a non-receptor tyrosine kinase acting as signaling mediator of different stimuli, behaves as tumor-suppressor in prostate. Since, PYK2 and RSV share several fields of interaction, including oxidative stress, we have investigated their functional relationship in human non-transformed prostate EPN cells and in their tumor-prone counterpart EPN-PKM, expressing a PYK2 dead-kinase mutant. We show that RSV has a strong biological activity in both cell lines, decreasing ROS production, inducing morphological changes and reversible growth arrest, and activating autophagy but not apoptosis. Interestingly, the PYK2 mutant increases basal ROS and autophagy levels, and modulates the intensity of RSV effects. In particular, the anti-oxidant effect of RSV is more potent in EPN than in EPN-PKM, whereas its anti-proliferative and pro-autophagic effects are more significant in EPN-PKM. Consistently, PYK2 depletion by RNAi replicates the effects of the PKM mutant. Taken together, our results reveal that PYK2 and RSV act on common cellular pathways and suggest that RSV effects on prostate cells may depend on mutational-state or expression levels of PYK2 that emerges as a possible mediator of RSV mechanisms of action. Moreover, the observation that resveratrol effects are reversible and not associated to apoptosis in tumor-prone EPN-PKM cells suggests caution for its use in humans.     

Energy consumption of residential buildings and occupancy profiles. A case study in Mediterranean climatic conditions

Residential energy consumptions are determined by the interaction of many factors. Apart from physical characteristics such as climate, heating type, age, and size of the house, occupants’ behavior and socio-economic aspects are critical. Furthermore, the relative impact of the occupants’ characteristics and behavior seems to differ in various investigations confirming the importance of contextual analysis. In this study, different procedures for obtaining occupancy profiles are described and applied with reference to a residential building stock located in Mediterranean climatic conditions (Italy). The heating and domestic hot water (DHW) energy consumptions and indoor comfort conditions of a representative building were determined by introducing different occupant scenarios in dynamic simulations. The occupancy profiles were built by means of data collected at the University of Calabria using surveys, interviews, bills, and statistical elaborations. Considering different modes of use of the dwelling (Regulations, Current-use, and Statistical), in the simulation process, all the inputs of occupancy, ventilation, lighting, DHW, and heating operation were modified. The Regulations occupancy profile produces an underestimation of heating energy consumption. Additionally, primary energy for DHW is strongly affected by the family composition. The effect of the occupants’ preferences on the energy performance of the building was investigated: mainly energy consumptions and internal comfort conditions vary with the set point temperature and the duration of ventilation. The analysis provides reference procedures for obtaining occupancy profiles. Furthermore, the simulation results demonstrate the significant dependence of heating and DWH primary energy consumption on the characteristics and preferences of occupants in the Mediterranean climate.     

Application of Transglutaminase-Crosslinked Whey Protein/Pectin Films as Water Barrier Coatings in Fried and Baked Foods

Whey protein/pectin edible films were prepared in the presence of transglutaminase and tested as water barrier coatings of both fried doughnuts and french fries as well as of baked food like “taralli” biscuits. Our results demonstrated an undoubted effect of the produced hydrocolloidal films, known to markedly reduce water vapor permeability, in decreasing moisture loss in both doughnuts and french fries when applied before food frying. At the same time, a significant decrease in oil content was observed in the coated fried foods (about 50 % in doughnuts and 25 % in french fries) with respect to both uncoated controls and whey/soy protein-coated samples. No difference was observed between uncoated and coated both doughnuts and french fries with regard to their texture properties and as confirmed by the data from sensory evaluation tests. Furthermore, since the coating by edible films endowed with low water vapor permeability could be useful to prevent moisture absorption by baked foods, we tested the whey protein/pectin film prepared in the presence of transglutaminase, which was also used to coat taralli biscuits. The proposed methodology resulted to be effective to hinder moisture absorption by biscuits during a long storage period, keeping water content constant from 0 to 50 days, thus preventing the food matrix conversion from a glassy state to a rubbery state which is the major cause of baked food rejection by consumers.     

Investigation on the presence of sulphites in fresh meat preparations: estimation of an allowable maximum limit

Sulphiting agents are commonly used food additives. They are not allowed in fresh meat preparations. In this work, 2250 fresh meat samples were analysed to establish the maximum concentration of sulphites that can be considered as “natural” and therefore be admitted in fresh meat preparations. The analyses were carried out by an optimised Monier-Williams Method and the positive samples confirmed by ion chromatography. Sulphite concentrations higher than the screening method LOQ (10.0 mg · kg^− 1) were found in 100 samples. Concentrations higher than 76.6 mg · kg^− 1, attributable to sulphiting agent addition, were registered in 40 samples. Concentrations lower than 41.3 mg · kg^− 1 were registered in 60 samples. Taking into account the distribution of sulphite concentrations obtained, it is plausible to estimate a maximum allowable limit of 40.0 mg · kg^− 1 (expressed as SO₂). Below this value the samples can be considered as “compliant”.     

A new SCAR marker potentially useful to distinguish Italian cattle breeds

In recent years, the safeguarding of Italian native cattle breeds has increased the recovery of these breeds and the promotion of their products by enhancing the application of useful methods to trace the origin of meat products. The random amplified polymorphic DNA sequence (RAPD–PCR) followed by characterised amplified region (SCAR) marker approach could be considered an advantageous method to ensure food quality and origin, and represents a further opportunity to recover Italian autochthonous cattle breeds. Here, we report the results of RAPD–PCR using 42 primers and the development of two informative SCAR markers. Ten different clones for each cultivar-specific RAPD fragment were sequenced and database searches of sequence similarity were performed. The method enabled the detection of low amounts of DNA and, because of the relatively short dimension of the amplicon, it was suitable for the analysis of potentially degraded DNA obtained from processed commercial food that contained meat as an ingredient.     

Antiproliferative and antioxidant effects on breast cancer cells of oleuropein and its semisynthetic peracetylated derivatives

Olive leaves extracts are a natural source of polyphenols, mainly oleuropein, widely considered to be potentially beneficial for health. This study focused on evaluation of the anti-tumoural activities of some oleuropein peracetylated derivatives, obtained with “green chemical” methodologies, against two human breast cancer cell lines. MCF-7 and T-47D cells were treated with oleuropein, peracetylated oleuropein, peracetylated aglycone and peracetylated hydroxytyrosol and the effects on growth and viability were investigated. Antioxidant effects were analysed after treatment with hydrogen peroxide. The peracetylated compounds exerted higher antiproliferative effects than oleuropein, by an arrest of cell cycle progression, associated with a strong antioxidant activity. Our results demonstrate that olive leaves, a by-product of olive manufacture, may provide a precious source of chemical derivatives, obtainable by peracetylation of oleuropein derivatives, which provide beneficial properties for human health.