Expression of UDP-glucuronosyltransferase 1A6 isoform in Caco-2 cells stimulated with lipopolysaccharide

Glucuronidation is an important metabolic process of detoxification in all vertebrates. The reaction is catalyzed by a multigene family of UDP-glucuronosyltransferases (UGTs) able to convert many xenobiotics and endobiotics (hydrophobic substances) to inactive, water-soluble glucuronides. The UGTs play a protective role, facilitating the elimination of potentially toxic metabolites via urine, bile and feces; therefore, impairment of UGTs may have important toxicological consequences. The regulation of UGTs during bacterial infection or inflammation is not well described. In this study, we investigated the in vitro effect of lipopolysaccharide (LPS) on the expression of the UGT1A6 isoform in human colon carcinoma Caco-2 cells. Results demonstrated a significant down-regulation of UGT1A6 expression, both in terms of mRNA and protein levels, and a reduced UGT activity after LPS exposure of cell cultures, suggesting a role for endotoxins on UGT regulation mechanisms

Membrane Microvesicles as Actors in the Establishment of a Favorable Prostatic Tumoral Niche: A Role for Activated Fibroblasts and CX3CL1-CX3CR1 Axis

Tumor microenvironment is enriched in plasma membrane microvesicles (MV) shed from all cell types that constitute the tumor mass, reflecting the antigenic profile of the cells they originate from. Fibroblasts and tumor cells mutually communicate within tumor microenvironment. Recent evidences suggest that tumor-derived MVs (TMV) exert a broad array of biological functions in cell-to-cell communication. To elucidate their role in cancer-to-fibroblast cell communication, TMV obtained from two prostate carcinoma cell lines with high and weak metastatic potential (PC3 and LnCaP, respectively) have been characterized. TMV exhibit matrix metalloproteinases (MMP) and extracellular MMP inducer at their surface, suggesting a role in extracellular matrix degradation. Moreover, TMV not only induce the activation of fibroblasts assessed through extracellular signal-regulated kinase 1/2 phosphorylation and MMP-9 up-regulation, increase motility and resistance to apoptosis but also promote MV shedding from activated fibroblasts able in turn to increase migration and invasion of highly metastatic PC3 cells but not LnCaP cells. PC3 cell chemotaxis seems, at least partially, dependent on membrane-bound CX3CL1/fractalkine ligand for chemokine receptor CX3CR1. The present results highlight a mechanism of mutual communication attributable not only to soluble factors but also to determinants harbored by MV, possibly contributing to the constitution of a favorable niche for cancer development. [Cancer Res 2009;69(3):785–93

Cyclooxygenase-2-Derived Prostacyclin Protective Role on Endotoxin-Induced Mouse Cardiomyocyte Mortality

Cardiovascular dysfunction characterizes septic shock, inducing multiple organ failure and a high mortality rate. In the heart, it has been shown an up-regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions with subsequent overproduction of nitric oxide (NO) and eicosanoids. This study is focused on the links between these products of inflammation and cell loss of mouse cardiomyocytes during treatment by the Salmonella typhimurium lipopolysaccharide (LPS) in presence or in absence of NOS or COX inhibitors. LPS induced RelA/NF-κB p65 activation, iNOS and COX-2 up-regulations, resulting in NO and prostacyclin releases. These effects were reversed by the NO-synthase inhibitor and increased by the specific COX-2 inhibitor. Immunostainings with FITC-conjugated anti-Annexin-V and propidium iodide and caspase 3/7 activity assay showed that cardiomyocyte necrosis was inhibited by L-NA during LPS treatment challenge, while apoptosis was induced in presence of both LPS and NS-398. No effect on LPS cellular injury was observed using the specific cyclooxygenase-1 (COX-1) inhibitor, SC-560. These findings strongly support the hypothesis of a link between iNOS-dependent NO overproduction and LPS-induced cell loss with a selective protective role allotted to COX-2 and deriving prostacyclins

New Insights into the Evolution and Gene Structure of the Mitochondrial Carrier Family Unveiled by Analyzing the Frequent and Conserved Intron Positions

Mitochondrial carriers (MCs) belong to a eukaryotic protein family of transporters that in higher organisms is called the solute carrier family 25 (SLC25). All MCs have characteristic triplicated sequence repeats forming a 3-fold symmetrical structure of a six-transmembrane α-helix bundle with a centrally located substrate-binding site. Biochemical characterization has shown that MCs altogether transport a wide variety of substrates but can be divided into subfamilies, each transporting a few specific substrates. We have investigated the intron positions in the human MC genes and their orthologs of highly diversified organisms. The results demonstrate that several intron positions are present in numerous MC sequences at the same specific points, of which some are 3-fold symmetry related. Many of these frequent intron positions are also conserved in subfamilies or in groups of subfamilies transporting similar substrates. The analyses of the frequent and conserved intron positions in MCs suggest phylogenetic relationships not only between close but also distant homologs as well as a possible involvement of the intron positions in the evolution of the substrate specificity diversification of the MC family members

Anti-Ro and anti-La autoantibodies induce TNF-α production by human salivary gland cells: an in vitro study

Obiettivo: Lo scopo di questo studio e stato valutare la produzione di TNF-α, induttore della via estrinseca del processo apoptotico, in seguito al trattamento con gli autoanticorpi anti-Ro ed anti-La isolati da pazienti con sindrome di Sjogren primaria in un modello sperimentale rappresentato dalla linea cellulare di ghiandole salivari umane, A- 253. E stata, inoltre, valutata la presenza sulla superficie di tali cellule di recettori specifici per tale induttore, TNFR1 e TNFR2. Materiali e metodi: Gli autoanticorpi anti-La ed anti-Ro sono stati purificati su una colonna cromatografia ad alta affinita. Le metodiche utilizzate per la valutazione della produzione di TNF-α e lo studio dei recettori di superficie sono state immunofluorescenza, RT-PCR e saggi immunoenzimatici. Risultati: I nostri risultati hanno dimostrato che le cellule A-253 esprimono in superficie i recettori TNFR1 e TNFR2 e che gli autoanticorpi anti-Ro e anti-La sono in grado di indurre la produzione di TNF-α nelle stesse cellule. Conclusioni: Il trattamento con gli autoanticorpi anti-Ro ed anti-La induce la produzione di TNF-α in cellule di ghiandole salivari umane e questo potrebbe spiegare la attivazione della via estrinseca della apoptosi

Caratterizzazione idrogeologica della piana di Metaponto, qualità e rischi di degrado delle acque sotterranee

The study area falls within the Ionian coastal plain (Southern Italy), bounded on the West by the Sinni River and on the East by Bradano River. It covers 40 km along the coast and 6 km inland. The geological and hydrogeological features of the study area and the chemical-physical groundwater characterisation have been inferred from the data analysis of 1130 boreholes. Some aquifers, connected among them, constituted by soils of different geological origin, exist in the area also if the coastal plain aquifer is the most interesting for practical utilisation. Groundwater flow is mainly unconfined inland, where the aquifer is constituted by terraced deposits and confined in the alluvial coastal plain. An upper clayey layer overlies the sandy coastal aquifer characterised by a mean hydraulic conductivity value equal to 2.3 10-4 m/s. Being the direct natural recharge extremely low, the recharge of this coastal aquifer is mainly guaranteed by the discharge from upward aquifers and from the river leakage. The bottom of the aquifer is a silty-clayey bed which lies under the sea level permitting so the seawater intrusion. This phenomenon involves the studied coastal plain for a width of 1-1.5 km on average and it is less evident moving inwards where the altitude of the clayey bottom of the aquifer becomes progressively higher than the sea level. Other chemical-physical data, studied to determine the quality of the waters, showed that the pollution of the groundwater is considered a grave environmental problem for the studied area

La valutazione della vulnerabilità integrata degli acquiferi. La sperimentazione nell'area campione di Corigliano in Salento

Si descrivono le metodologie utilizzate e i risultati conseguiti con uno studio di dettaglio di un’area campione dell’unità idrogeologica del Salento (Puglia), costituita da un vasto acquifero carbonatico mesozoico. Tale area, rappresentativa sia degli aspetti idrogeologici tipici delle zone di alimentazione del Salento sia degli effetti dell'antropizzazione, è sede di nurnerosi pozzi adibiti ad uso potabile. Lo studio è stato finalizzato alla redazione della carta della vulnerabilità dell’acquifero con ii metodo SINTACS. La natura sperimentale dell’applicazione è legata alle peculiarità dell’acquifero salentino e all’assenza di esperienze pregresse per tale contesto. Sono stati effettuati rilievi diretti, prove idrogeologiche e piü cicli di campionarnento idrico ed analisi di laboratorio. I centri di pericolo sono stati censiti sulla base delle banche dati disponibili ed ispezionando ii territorio. L’infiltrazione si è dirnostrata molto rapida, anche laddove l’acquifero non affiora. La vulnerabilità è risultata notevole, da alta a molto elevata. La qualita delle acque, per quanto tuttora buona, si è dimostrata sensibile alla posizione e all’azione dei centri di pericolo. I rischi di degrado qualitativo sono risultati non trascurabili

Implementation of Designed PV Integrated Controlled Converter System

Photovoltaic (PV) energy has increased drastically at an average annual rate of 60% in the last few years. It quickly became an integral part of the power system networks. This increase, in turn, has triggered the evolution of PV power converters with more efficiency and reliability. In this paper, a prototype of the PV integrated controlled converter system is designed, which is applicable in water pumping for irrigation. Main components of this system are floating dual boost converter (FDBC), three-phase voltage source inverter (VSI) and three-phase squirrel cage induction motor (pump). For address the issue of PV voltage fluctuations, a voltage mode controller is designed for the FDBC which regulates the output voltage of the FDBC to a fixed value irrespective of any voltage fluctuations at the PV side