115 research outputs found

    Human adenocarcinoma cell line sensitivity to essential oil phytocomplexes from pistacia species: A multivariate approach

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    Principal component analysis (PCA) multivariate analysis was applied to study the cytotoxic activity of essential oils from various species of the Pistacia genus on human tumor cell lines. In particular, the cytotoxic activity of essential oils obtained from P. lentiscus, P. lentiscus var. chia (mastic gum), P. terebinthus, P. vera, and P. integerrima, was screened on three human adenocarcinoma cell lines: MCF-7 (breast), 2008 (ovarian), and LoVo (colon). The results indicate that all the Pistacia phytocomplexes, with the exception of mastic gum oil, induce cytotoxic effects on one or more of the three cell lines. PCA highlighted the presence of different cooperating clusters of bioactive molecules. Cluster variability among species, and even within the same species, could explain some of the differences seen among samples suggesting the presence of both common and species-specific mechanisms. Single molecules from one of the most significant clusters were tested, but only bornyl-acetate presented cytotoxic activity, although at much higher concentrations (IC50 = 138.5 \ub5g/mL) than those present in the essential oils, indicating that understanding of the full biological effect requires a holistic vision of the phytocomplexes with all its constituents

    Pregnane X receptor and constitutive androstane receptor modulate differently CYP3A-mediated metabolism in earlyand late-stage cholestasis

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    AIM: To ascertain whether cholestasis affects the expression of two CYP3A isoforms (CYP3A1 and CYP3A2) and of pregnane X receptor (PXR) and constitutive androstane receptor (CAR). METHODS: Cholestasis was induced by bile duct ligation in 16 male Wistar rats; whereas 8 sham-operated rats were used as controls. Severity of cholestasis was assessed on histological examination of liver sections, and serum concentrations of albumin, AST, ALT, GGT, ALPK and bilirubin. Gene and protein expressions of PXR, CAR, CYP3A1 and CYP3A2 were assessed by means of qRT-PCR and Western blot, respectively. Alterations in CYP3A activity were measured by calculating the kinetic parameters of 4-OH and 1'-OH-midazolam hydroxylation, marker reactions for CYP3A enzymes. RESULTS: The mRNA and protein expression of CYP3A1 increased significantly in mild cholestasis (P < 0.01). At variance, mRNA and protein expression of CYP3A2 didn't change in mild cholestasis, whereas the expression and activity of both CYP3A1 and CYP3A2 decreased dramatically when cholestasis became severe. Consistently with these observations, the nuclear expression of both PXR and CAR, which was measured because they both translocate into the cell nucleus after their activation, virtually disappeared in the late stage of cholestatic injury, after an initial increase. These results indicate that early- and late-stage cholestasis affects CYP3A-mediated drug metabolism differently, probably as consequence of the different activation of PXR and CAR. CONCLUSION: Early- and late-stage cholestasis affects CYP3A-mediated drug metabolism differently. PXR and CAR might be targeted therapeutically to promote CYP3A-mediated liver detoxification

    Activity of Aloe arborescens leaf extracts: in vitro effects on Human Adenocarcinoma HT-29 cell line and free-radical species.

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    Aloe arborescens Mill. (syn. Candelabra Aloe; Xanthorrhoeaceae) is native to South Africa; in Italy it is grown for ornamental, therapeutic and cosmetic uses. Various Aloe spp. have been used since ancient times and have a well-documented history of use as medicines. Nowadays, it is widely studied as potential anticancer, antidiabetic, antimicrobial and for several other uses. The presence of aloin, aloe-emodin, polysaccharides, mannose and acemannan was reported in whole-leaf preparations. The aim of the present research was to study Aloe arborescens leaf extracts, also to improve the uses of Aloe since many products are marketed also in Western countries. For this purpose, methanolic and ethanolic extracts were obtained from freeze-dried leaves, and then studied using: a) HPLC-DAD analysis to determine aloins and aloe-emodin contents, b) two radical-scavenging assays to assess the radical scavenger activity, and 3) MTT assay on colorectal adenocarcinoma cell line (HT29 cells) to evaluate cell viability

    Alternative evaluation methods for roundness measurements

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    Requirements to roundness tolerances are a part of the geometrical product specifications. However, the definition for the roundness tolerance according to ISO 1101 considering radial deviations only is not sufficient to assure the functionality of many products. In addition, the form of roundness deviations along the circumference plays a significant rule for rotating machine components. Especially periodic deviations cause vibrations that lead to noise and wear. The Fourier analysis and the corresponding amplitude spectrum deliver information about the properties of the form derived from the magnitude of the different harmonics. This information presents a series of results depending on the harmonics. Therefore, a dedicated tolerance definition in most cases in from of a mathematical equation is used. The currently used tolerance definitions are not standardized and difficult to understand. Often, only one amplitude of the spectrum is significantly larger than the others are and effects functionality. In this case, an algorithm that detects the largest amplitude enables an easier tolerance definition

    Western Diet-Induced Metabolic Alterations Affect Circulating Markers of Liver Function before the Development of Steatosis

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    Since nutrition might have a significant impact on liver function, we analyzed the early effect of Western-type diet on hepatic tissue and lipid and drug metabolism in Wistar-Kyoto rats (n = 8); eight rats fed with a standard diet were used as controls. Histological analysis of liver tissue was performed, and plasma biochemical parameters were measured. Plasma concentration of six bile acids was determined by ultra-liquid chromatography-tandem mass spectrometry UHPLC-MS/MS. Hepatic gene expressions of enzymes involved in drug and lipid metabolism were assessed by means of real-time reverse transcription (qRT)-PCR. Liver of rats fed with a Western diet did not show macroscopic histological alterations, but number and diameter of lipid droplets increased, as well as DGAT1, GPAT4, SCD, FASN and SREBP2 expression. Furthermore, Western diet-fed animals showed an increase in the activation of hepatic stellate cells and macrophage number in liver tissue, as well as a significant increase in AST and bilirubin levels (p < 0.01), and in the LDL:HDL cholesterol ratio (p < 0.001). Plasma chenodeoxycholic acid concentration increased significantly, whereas cholic acid decreased (p < 0.05), and cytochrome P450 genes were generally downregulated. Significant changes in hepatic lipid and drug metabolism are early induced by the Western diet, prior to steatosis development. Such changes are associated with a peculiar alteration in circulating bile acids, which could represent an early marker of non-alcoholic fatty liver disease (NAFLD) development

    Anti-HER2 Super Stealth Immunoliposomes for Targeted-Chemotherapy

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    : Liposomes play an important role in the field of drug delivery by virtue of their biocompatibility and versatility as carriers. Stealth liposomes, obtained by surface decoration with hydrophilic polyethylene glycol (PEG) molecules, represented an important turning point in liposome technology, leading to significant improvements in the pharmacokinetic profile compared to naked liposomes. Nevertheless, the generation of effective targeted liposomes - a central issue for cancer therapy - has faced several difficulties and clinical phase failures. Active targeting remains a challenge for liposomes. In this direction, we designed a new Super Stealth Immunoliposomes (SSIL2) composed of a PEG-bi-phospholipids derivative that stabilizes the polymer shielding over the liposomes. Furthermore, its counterpart, conjugated to the fragment antigen-binding of trastuzumab (Fab'TRZ -PEG-bi-phospholipids), is firmly anchored on the liposomes surface and correctly orients outward the targeting moiety. Throughout this study, the performances of SSIL2 are evaluated and compared to classic stealth liposomes and stealth immunoliposomes in vitro in a panel of cell lines and in vivo studies in zebrafish larvae and rodent models. Overall, SSIL2 shows superior in vitro and in vivo outcomes, both in terms of safety and anticancer efficacy, thus representing a step forward in targeted cancer therapy, and valuable for future development. This article is protected by copyright. All rights reserved

    Pharmacological Applications of Bile Acids and Their Derivatives in the Treatment of Metabolic Syndrome

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    Apart from well-known functions of bile acids in digestion and solubilization of lipophilic nutrients and drugs in the small intestine, the emerging evidence from the past two decades identified the role of bile acids as signaling, endocrine molecules that regulate the glucose, lipid, and energy metabolism through complex and intertwined pathways that are largely mediated by activation of nuclear receptor farnesoid X receptor (FXR) and cell surface G protein-coupled receptor 1, TGR5 (also known as GPBAR1). Interactions of bile acids with the gut microbiota that result in the altered composition of circulating and intestinal bile acids pool, gut microbiota composition and modified signaling pathways, are further extending the complexity of biological functions of these steroid derivatives. Thus, bile acids signaling pathways have become attractive targets for the treatment of various metabolic diseases and metabolic syndrome opening the new potential avenue in their treatment. In addition, there is a significant effort to unveil some specific properties of bile acids relevant to their intrinsic potency and selectivity for particular receptors and to design novel modulators of these receptors with improved pharmacokinetic and pharmacodynamic profiles. This resulted in synthesis of few semi-synthetic bile acids derivatives such as 6a-ethyl-chenodeoxycholic acid (obeticholic acid, OCA), norursodeoxycholic acid (norUDCA), and 12-monoketocholic acid (12-MKC) that are proven to have positive effect in metabolic and hepato-biliary disorders. This review presents an overview of the current knowledge related to bile acids implications in glucose, lipid and energy metabolism, as well as a potential application of bile acids in metabolic syndrome treatment with future perspectives
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