3,298 research outputs found

    Measurement of H<sub>2</sub>O<sub>2</sub> within living drosophila during aging using a ratiometric mass spectrometry probe targeted to the mitochondrial matrix

    Get PDF
    Hydrogen peroxide (H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt;) is central to mitochondrial oxidative damage and redox signaling, but its roles are poorly understood due to the difficulty of measuring mitochondrial H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; in vivo. Here we report a ratiometric mass spectrometry probe approach to assess mitochondrial matrix H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; levels in vivo. The probe, MitoB, comprises a triphenylphosphonium (TPP) cation driving its accumulation within mitochondria, conjugated to an arylboronic acid that reacts with H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; to form a phenol, MitoP. Quantifying the MitoP/MitoB ratio by liquid chromatography-tandem mass spectrometry enabled measurement of a weighted average of mitochondrial H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; that predominantly reports on thoracic muscle mitochondria within living flies. There was an increase in mitochondrial H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; with age in flies, which was not coordinately altered by interventions that modulated life span. Our findings provide approaches to investigate mitochondrial ROS in vivo and suggest that while an increase in overall mitochondrial H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt; correlates with aging, it may not be causative

    Polymer based silver nanocomposites as versatile solid film and aqueous emulsion SERS substrates

    Get PDF
    Nanocomposites containing Ag nanoparticles (average diameter similar to 11 nm) dispersed in poly(tertbutylacrylate) were prepared by in situ polymerization via miniemulsions and constitute active and versatile SERS substrates. The use of this synthetic strategy enables the dual use of the final composites as SERS substrates, both as aqueous emulsions and as cast films, shown here by several measurements using thiosalicylic acid as the testing analyte. The main advantage of these types of materials is related to the potential to scale up and the widespread use of handy substrates, using technology already available. This requires homogeneous composite substrates with SERS activity and this was demonstrated here by means of confocal Raman microscopy. Finally, a series of experiments were carried out on Ag/polymer nanocomposites submitted to temperature variations below and above the polymer glass transition temperature (T(g)) in order to conclude about the effect of temperature processing conditions on the composites' SERS activity.FCT- SFRH/BD/66460/2009FCT- SFRH/BPD/66407/2009FCT- PTDC/QUI/67712/ 2006RNME-Pole UA-FCT Project REDE/1509/RME/200

    Ezetimibe/Simvastatin 10/20 mg versus Rosuvastatin 10 mg in high-risk hypercholesterolemic patients stratified by prior statin treatment potency

    Get PDF
    <p>Abstract</p> <p>Objective</p> <p>This <it>post-hoc </it>analysis compared the lipid-altering efficacy of Ezetimibe/Simvastatin 10/20 mg (EZ/Simva) versus Rosuvastatin 10 mg (Rosuva) in patients stratified by statin potency/dose prior to randomization.</p> <p>Methods</p> <p>Patients with elevated low-density lipoprotein cholesterol (LDL-C) despite prior statin treatment (n = 618) were randomized 1:1 to EZ/Simva 10/20 mg or Rosuva 10 mg for 6 weeks. Percent change from baseline in lipids and attainment of lipid targets were assessed within each subgroup (low potency n = 369, high potency n = 249). Consistency of the treatment effect across subgroups was evaluated by testing for treatment-by-subgroup interaction. No multiplicity adjustments were made.</p> <p>Results</p> <p>Significant treatment-by-subgroup interaction occurred for LDL-C (p = 0.013), total cholesterol (p = 0.025), non-HDL-C (p = 0.032), and apolipoprotein B (p = 0.016) with greater between-treatment differences in favor of EZ/Simva observed in patients from the high potency stratum vs low potency stratum. Individual and triple target attainment was higher for Eze/Simva compared with Rosuva in both strata.</p> <p>Conclusions</p> <p>Compared with Rosuva, switching to EZ/Simva provided greater reductions in LDL-C, total cholesterol, non-HDL-C and apolipoprotein B and higher target attainment in patients on prior statin treatment, regardless of potency, although patients treated with higher potency statins prior to randomization experienced greater between treatment differences in favor of EZ/Simva.</p> <p>Trial Registration</p> <p>Registered at ClinicalTrials.gov: NCT00479713</p

    Efficacy of Ezetimibe/Simvastatin 10/20 mg Versus Rosuvastatin 10 mg in High-Risk Patients With or Without Obesity

    Get PDF
    Introduction: This post-hoc analysis compared the effects of switching to ezetimibe/simvastatin 10/20 mg (EZE/SIMVA) or rosuvastatin 10 mg (ROSUVA) in high-risk hypercholesterolemic patients with/without obesity. Methods: Patients (n=618) at high-risk for coronary heart disease with elevated low-density lipoprotein cholesterol (LDL-C) ≥2.59 and ≤4.92 mmol/L, while on a statin, entered a 6-week open-label stabilization/screening period during which they continued on the same statin. Patients were then randomized 1:1 to double-blind EZE/SIMVA 10/20 mg or ROSUVA 10 mg for 6 weeks. Patients were classified as non-obese (n=437) or obese (n=180) based on body mass index 0.050 for all). Conclusions: In this post-hoc analysis of high-risk patients with elevated LDL-C, despite prior use of statin therapy, switching to EZE/SIMVA 10/20 mg versus ROSUVA 10 mg provided superior reductions in LDL-C, TC, and non-HDL-C in obese and non-obese patients

    Long-term treatment with chaethomellic acid A reduces glomerulosclerosis and arteriolosclerosis in a rat model of chronic kidney disease

    Get PDF
    The high prevalence of end-stage renal disease emphasizes the failure to provide therapies to effectively prevent and/or reverse renal fibrosis. Therefore, the aim of this study was to evaluate the effect of long-term treatment with chaethomellic acid A (CAA), which selectively blocks Ha-Ras farnesylation, on renal mass reduction-induced renal fibrosis. Male Wistar rats were sham-operated (SO) or subjected to 5/6 renal mass reduction (RMR). One week after surgery, rats were placed in four experimental groups: SO:SO rats without treatment (n = 13); SO + CAA: SO rats treated with CAA (n = 13); RMR:RMR rats without treatment (n = 14); and RMR + CAA:RMR rats treated with CAA (n = 13). CAA was intraperitoneally administered in a dose of 0.23 μg/kg three times a week for six months. Renal fibrosis was evaluated by two-dimensional ultrasonography and histopathological analysis. The kidneys of the RMR animals treated with CAA showed a significantly decrease in the medullary echogenicity (p < 0.05) compared with the RMR rats that received no treatment. Glomerulosclerosis and arteriolosclerosis scores were significantly lower (p < 0.001) in the RMR + CAA group when compared with the RMR group. There were no significant differences in interstitial fibrosis, interstitial inflammation and tubular dilatation scores between the RMR + CAA and RMR groups. These data suggest that CAA can be a potential future drug to attenuate the progression of chronic kidney disease.This work is supported by : European Investment Funds by FEDER/COMPETE/POCI– Operacional Competitiveness and Internacionalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT - Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013; and by European Investment Funds by FEDER/COMPETE/POCI– Operacional Competitiveness and Internacionalization Programme, under Project POCI-01-0145-FEDER-016728 and National Funds by FCT - Portuguese Foundation for Science and Technology, under the project PTDC/DTP-DES/6077/2014.info:eu-repo/semantics/publishedVersio

    Lipid-based nanostructures as a strategy to enhance curcumin bioaccessibility: behavior under digestion and cytotoxicity assessment

    Get PDF
    The aim of this study was to evaluate the behavior of different lipid-based nanostructures during in vitro digestion, in particular on curcumins bioaccessibility, and to access their potential toxicity. Solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions (NE) were submitted to harmonized static in vitro digestion and their cytotoxicity and cellular transport were evaluated using Caco-2 cell line. NE presented the highest curcumins bioaccessibility followed by NLC and SLN, 71.1%, 63.7% and 53.3%, respectively. Free fatty acids percentage increased in the following order: NLC ? NE < SLN. Non-digested nanostructures and excipients presented no cytotoxicity; however, digested NE and NLC presented cytotoxicity due to MCT oil, which presented cytotoxicity after digestion. The apparent permeability coefficient of NLC was higher than SLN and NE. These results showed that lipid-based nanostructures physical state and composition have a high influence on particles' behavior during digestion, and on their cytotoxicity/intestinal permeability, and highlights the importance of conducting cytotoxicity assessments after in vitro digestion. This work contributes to a better understanding of the behavior of lipid-based nanostructures under digestion/adsorption, and this knowledge will be useful in design of nanostructures that afford both safety and an increased bioactive compounds bioavailability.Acknowledgments Raquel F. S. Goncalves acknowledge the Foundation for Science and Technology (FCT) for her fellowship (SFRH/BD/140182/2018) . This study was supported by Foundation for Science and Technology (FCT) under the scope of Project PTDC/AGRTEC/5215/2014, the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020Programa Operacional Regional do Norte. Funding from INTERFACE Programme through the Innovation, Technology and Circular Economy Fund (FITEC) and iNova4Health, a program also financially supported by Fundacao para a Ciencia eTecnologia, is also gratefully acknowledged.info:eu-repo/semantics/publishedVersio
    corecore