¹H NMR and Multivariate Analysis for Geographic Characterization of Commercial Extra Virgin Olive Oil: A Possible Correlation with Climate Data.

¹H Nuclear Magnetic Resonance (NMR) spectroscopy coupled with multivariate analysis has been applied in order to investigate metabolomic profiles of more than 200 extravirgin olive oils (EVOOs) collected in a period of over four years (2009-2012) from different geographic areas. In particular, commercially blended EVOO samples originating from different Italian regions (Tuscany, Sicily and Apulia), as well as European (Spain and Portugal) and non-European (Tunisia, Turkey, Chile and Australia) countries. Multivariate statistical analysis (Principal Component Analisys (PCA) and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA)) applied on the NMR data revealed the existence of marked differences between Italian (in particular from Tuscany, Sicily and Apulia regions) and foreign (in particular Tunisian) EVOO samples. A possible correlation with available climate data has been also investigated. These results aim to develop a powerful NMR-based tool able to protect Italian olive oil productions.

JNK/p53 mediated cell death response in K562 exposed to etoposide-ionizing radiation combined treatment.

The study of the ability of chemotherapeutic agents and/or ionizing radiation (IR) to induce cell death in tumor cells is essential for setting up new and more efficient therapies against human cancer. Since drug and ionizing radiation resistance is an impediment to successful chemotherapy against cancer, we wanted to check if etoposide/ionizing radiation combined treatment could have a synergic effect to improve cell death in K562, a well-known human erythroleukemia ionizing radiation resistant cell line. In this study, we examined the role played by JNK/SAPK, p53, and mitochondrial pathways in cell death response of K562 cells to etoposide and IR treatment. Our results let us suppose that the induction of cell death, already evident in 15 Gy exposed cells, mainly in 15 Gy plus etoposide, may be mediated by JNK/SAPK pathway. Moreover, p53 is a potential substrate for JNK and may act as a JNK target for etoposide and ionizing radiation. Thus further investigation on these and other molecular mechanisms underlying the cell death response following etoposide and ionizing radiation exposure could be useful to overcome resistance mechanisms in tumor cells.

PI-3K/Akt and NF-kappaB/IkappaBalpha pathways are activated in Jurkat T cells in response to TRAIL treatment.

The aim of this work was to evaluate the involvement of survival pathways in the response of Jurkat T leukaemic cells sensitive to the cytotoxic action of tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)/Apo2L. Jurkat T cells express TRAIL-R2/DR5 and TRAIL-R4/DcR2 receptors and start to die by apoptosis early (3 h) upon TRAIL administration reaching a dose-dependent increase in the percentage of dead cells within 48 h (up to 85-90%). This increase in cell death is accompanied by a dose-dependent significant (P < 0.05) increase in the G0/G1 phase of the cell cycle and reverted by the treatment with a broad inhibitor of caspases, z-VAD-fmk. Co-treatment of the cells with inhibitors of PI-3 kinase (LY294002) and nuclear factor kappa B (NF-kappaB) (SN50) pathways leads to an earlier significantly increased cytotoxicity, respectively in the form of apoptosis and necrosis. Consistently with the data obtained with the pharmacological inhibitors, the activation and nuclear translocation of both PI-3K and NF-kappaB were observed. In summary, our results provide evidence that even in sensitive neoplastic cells TRAIL paradoxically activates pro-survival pathways, which protect against TRAIL-mediated death since their inhibition leads to an earlier and increased cytotoxicity.

Molecular and morphological modifications occurring in rat heart exposed to intermittent hypoxia: role for protein kinase C alpha.

Exposure of rats to intermittent hypoxia determines different responses at tissue and cell level. Heart mainly undergoes the effects of hypoxic injury and its response is determined both by the relationship between oxygen supply and demand and by its functional state. Since molecular mechanisms mediate cells sensing and response to low O(2) concentration, here we explore the role played by Protein Kinase C alpha (PKC alpha) in the signal transduction mechanisms leading to the occurrence of morphological responses in rat neonatal, young and old heart subjected to intermittent hypoxia. Along with a key role for hypoxia inducible factor and vascular endothelial growth factor in the occurrence of continuous state of dynamic adaptation of vasculature, PKC alpha presumably phosphorylates IkBalpha in rat normoxic and hypoxic neonatal hearts, supporting the hypothesis of a rescue strategy carried out against hypoxia, together with an hypertrophic response. In hypoxic young heart PKC alpha activation, paralleled by sustained Bax homodimerization and caspase-3 activation, along with reduced p-IKBalpha and Inhibiting Apoptosis Protein (IAP) expression, suggests that the young early and deeply undergoes the effects of lowered oxygen tension. In addition, since no modifications concerning PKC alpha driven signalling system are evidenced in both the experimental conditions, we suggest an oxygen impaired sensing during ageing.

NF-kappaB activation plays an antiapoptotic role in human leukemic K562 cells exposed to ionizing radiation.

Exposure of cells to ionizing radiation (IR) determines cellular lesions, such as DNA and membrane damage, which involve a coordinate network of signal transduction pathways responsible for resistance to or delay of apoptosis, depending on cell type and administered dose. Since, after IR exposure, the apoptotic profile appeared different in the two chosen cell lines K562 and Jurkat along with caspase-3 activation, we paid attention to the influence exerted by Protein kinase C delta on transcription factor NF-kappaB activation. Interestingly, K562 resist to IR carrying out a survival strategy which includes PKC delta/NF-kappaB pathway activation, probably mediated by novel IKKs and a role for PI-3-kinase in activating PKC delta at Thr 505 by PDK-1 phosphorylation is suggested. In addition, since caspase-3 is not activated in these cells upon ionizing radiation exposure, it could be supposed that NF-kappaB antagonizes apoptosis induction interfering with pathways which lead to caspase activation, may be by inducing expression of IAP, caspases 3, 7, 9, inhibitor. Thus NF-kappaB activation explains the resistance displayed by K562 to IR and drug potential interference directed to this protein could overcome apoptosis resistance in clinical settings.