Brayden D.J.,University College Dublin |
Brayden D.J.,Conway Institute |
Cryan S.-A.,Royal College of Surgeons in Ireland |
Cryan S.-A.,Trinity College Dublin |
And 3 more authors.
Drug Discovery Today | Year: 2015
High-content analysis (HCA) provides quantitative multiparametric cellular fluorescence data. From its origins in discovery toxicology, it is now addressing fundamental questions in drug delivery. Nanoparticles (NPs), polymers, and intestinal permeation enhancers are being harnessed in drug delivery systems to modulate plasma membrane properties and the intracellular environment. Identifying comparative mechanistic cytotoxicity on sublethal events is crucial to expedite the development of such systems. NP uptake and intracellular routing pathways are also being dissected using chemical and genetic perturbations, with the potential to assess the intracellular fate of targeted and untargeted particles in vitro. As we discuss here, HCA is set to make a major impact in preclinical delivery research by elucidating the intracellular pathways of NPs and the in vitro mechanistic-based toxicology of formulation constituents. © 2015 Elsevier Ltd.
Wallace M.,Conway Institute |
Wallace M.,Food For Health Ireland |
Hashim Y.Z.H.-Y.,Food For Health Ireland |
Hashim Y.Z.H.-Y.,International Islamic University Malaysia |
And 6 more authors.
Human Reproduction | Year: 2010
Background Characterization of the normal degree of physiological variation in the metabolomic profiles of healthy humans is a necessary step in the development of metabolomics as both a clinical research and diagnostic tool. This study investigated the effects of the menstrual cycle on 1H nuclear magnetic resonance (NMR) derived metabolomic profiles of urine and plasma from healthy women.Method SIn this study, 34 healthy women were recruited and a first void urine and fasting blood sample were collected from each woman at four different time points during one menstrual cycle. Serum hormone levels were used in combination with the menstrual calendar to classify the urine and plasma samples into five different phases i.e. menstrual, follicular, periovulatory, luteal and premenstrual. The urine and plasma samples were analysed using 1H NMR spectroscopy and subsequent data were analysed using principal component analysis (PCA) and partial least squares discriminant analysis.Result SPCA of the urine spectra showed no separation of samples based on the phases of the menstrual cycle. Multivariate analysis of the plasma spectra showed a separation of the menstrual phase and the luteal phase samples (R2 = 0.61, Q2 = 0.41). Subsequent analysis revealed a significant decrease in levels of glutamine, glycine, alanine, lysine, serine and creatinine and a significant increase in levels of acetoacetate and very low density lipoprotein (VLDL CH2) during the luteal phase.Conclusion SThese Result s establish a need to control for metabolic changes that occur in plasma due to the menstrual cycle in the design of future metabolomic studies involving premenopausal women.
Saldova R.,Conway Institute |
Fan Y.,University College Dublin |
Fitzpatrick J.M.,Materials Misericordiae University Hospital |
Watson R.W.G.,University College Dublin |
Rudd P.M.,Conway Institute
Glycobiology | Year: 2011
One of the most urgent requirements in prostate cancer diagnosis is the development of a blood-based test which would be able to distinguish prostate cancer from benign prostate hyperplasia (BPH). Previously published results found a significant difference between specific glycan levels in patients with advanced prostate cancer and healthy controls. N-Glycans from the whole serum glycoproteins were measured using our fully quantitative high-throughput N-glycan analysis in combination with exoglycosidase digestions in sera from 13 BPH and 34 prostate cancer samples (17 Gleason score 5 and 17 Gleason score 7). The levels of core-fucosylated biantennary glycans and α2-3- linked sialic acids were significantly increased in prostate cancer patients compared with patients with BPH. Triantennary trigalactosylated glycans and tetraantennary tetrasialylated glycans with outer arm fucose were significantly decreased, and tetraantennary tetrasialylated glycans increased in Gleason 7 compared with Gleason 5. All these glycans can distinguish prostate cancer patients from BPH or Gleason 7 from Gleason 5 prostate cancer patients better than the current clinical test, prostatespecific antigen; therefore, their measurement may provide a new noninvasive approach to diagnose prostate cancer. However, additional validation studies would need to be carried out to further support this finding. Decreases in triantennary trigalactosylated glycans and/or bisected corefucosylated biantennary monosialylated glycans and increases in tetraantennary tetrasialylated glycans correlate with perineural invasion, which could further help to diagnose tumor spread and predict patients' survival. © The Author 2010. Published by Oxford University Press.
Stead D.A.,University of Aberdeen |
Walker J.,University of Aberdeen |
Holcombe L.,Imperial College London |
Gibbs S.R.S.,Imperial College London |
And 5 more authors.
Proteomics | Year: 2010
Candida glabrata is a major fungal pathogen of humans, and the virulence of C. glabrata is increased by inactivation of the transcription factor, Ace2. Our previous examination of the effects of Ace2 inactivation upon the intracellular proteome suggested that the hypervirulence of C. glabrata ace2 mutants might be caused by differences in the secretome. Therefore in this study we have characterised the C. glabrata secretome and examined the effects of Ace2 inactivation upon this extracellular proteome. We have identified 31 distinct proteins in the secretome of wild-type C. glabrata cells by MS/MS of proteins that were precipitated from the growth medium and enriched by affinity chromatography on concanavalin A. Most of these proteins are predicted to be cell wall proteins, cell wall modifying enzymes and aspartyl proteinases. The endochitinase Cts1 and the endoglucanase Egt2 were not detected in the C. glabrata secretome following Ace2 inactivation. This can account for the cell separation defect of C. glabrata ace2 cells. Ace2 inactivation also resulted in the detection of new proteins in the C. glabrata secretome. The release of such proteins might contribute to the hypervirulence of ace2 cells. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.
Gibbons H.,Conway Institute |
Gibbons H.,Food For Health Ireland |
O'Gorman A.,Conway Institute |
O'Gorman A.,Food For Health Ireland |
And 2 more authors.
Current Opinion in Lipidology | Year: 2015
Purpose of Review: Metabolomics is emerging as a powerful tool for studying metabolic processes and in recent years, the applications in the area of nutrition have risen rapidly. The present review gives an overview of the current applications in the field of nutrition and identifies areas in need of advancement. Recent Findings: Applications in nutrition research can in general be divided into three main areas: identification of dietary biomarkers, study of diet-related diseases and identification of biomarkers of disease and application to dietary intervention studies as a tool to identify molecular mechanisms. Summary: Metabolomics has made a significant impact on all the areas identified above and is set to have a major impact on the study of diet-health relationships. Copyright © 2015 Wolters Kluwer Health, Inc.
Buhmann H.,University of Zürich |
Le Roux C.W.,Conway Institute |
Le Roux C.W.,Gothenburg University |
Bueter M.,University of Zürich
Best Practice and Research: Clinical Gastroenterology | Year: 2014
Currently the only effective treatment for morbid obesity with a proven mortality benefit is surgical intervention. The underlying mechanisms of these surgical techniques are unclear, but alterations in circulating gut hormone levels have been demonstrated to be at least one contributing factor. Gut hormones seem to communicate information from the gastrointestinal tract to the regulatory appetite centres within the central nervous system (CNS) via the so-called 'Gut-Brain-Axis'. Such information may be transferred to the CNS either via vagal or non-vagal afferent nerve signalling or directly via blood circulation. Complex neural networks, distributed throughout the forebrain and brainstem, are in control of feeding and energy homoeostasis. This article aims to review how appetite is potentially regulated by these gastrointestinal hormones. Identification of the underlying mechanisms of appetite and weight control may pave the way to develop better surgical techniques and new therapies in the future. © 2014 Elsevier Ltd. All rights reserved.
Krause M.,Institute of Technology Tallaght |
Krause M.,Conway Institute |
Rodrigues-Krause J.,Institute of Technology Tallaght |
Rodrigues-Krause J.,Conway Institute |
And 7 more authors.
Metabolism: Clinical and Experimental | Year: 2012
Background and Aims: Nitric oxide (NO·) exerts key regulatory functions including vasodilation and glucose uptake. Thus reduced NO· levels are associated with insulin resistance and hypertension. In this preliminary work we aimed to measure the levels of NO· metabolites in serum and skeletal muscle of obese and non-obese subjects, with or without type 2 diabetes mellitus (T2DM). Methods: Fifteen sedentary male participants [7 obese controls (C) vs 5 obese and 3 non-obese T2DM; age 54 ± 9 years] were selected according to their BMI (> 30 kg/m2 for obese and 23-27 kg/m2 for non-obese participants) and evaluated for fasted values of blood glucose, HbA1c, lipid profile, serum CRP (C-reactive protein), erythrocyte glutathione (GSH) metabolism, plasma adiponectin, leptin and cytokines (TNF-α and INFγ), serum and skeletal muscle nitric oxide metabolites (nitrite and nitrates; tNOx) and skeletal muscle nNOS and iNOS expression. Body composition was measured by whole body DEXA and muscle microbiopsy was performed in the vastus lateralis. Results: We found that serum tNOx (total nitrite/nitrate; μmol/L) was lower in obese T2DM group (12.7 ± 3.5) when compared with their controls (21.1 ± 2.4), although the non-obese group presented higher concentration of tNOx (33.8 ± 7.2). Skeletal muscle nNOS was higher in obese controls, lower in non-obese T2DM and undetected in obese T2DM. On the other hand, expression of iNOS had an inverse relationship with nNOS, showing higher expression in obese T2DM, decrease in non-obese T2DM and absence in obese control group. tNOx levels (μmol/mg protein) were decreased in the non-obese T2DM group (12.07 ± 0.59) when compared with the obese control (21.68 ± 6.2) and the obese T2DM group (26.3 ± 7.26). Conclusion: We conclude that the decreased serum NO · production in obese T2DM patients seems to be associated with adipose mass as lower adiposity was associated with normal NO · which was reduced in the skeletal muscle of the non-obese T2DM patients. We suggest that the lower adiposity (and higher adiponectin) in non-obese T2DM could be responsible for differential levels of NO · production and insulin resistance. © 2012 Elsevier Inc. All rights reserved.
Rowan S.C.,Conway Institute |
Keane M.P.,St Vincents University Hospital |
Gaine S.,National University of Ireland |
McLoughlin P.,Conway Institute
The Lancet Respiratory Medicine | Year: 2016
Pulmonary hypertension is a well recognised complication of chronic hypoxic lung diseases, which are among the most common causes of death and disability worldwide. Development of pulmonary hypertension independently predicts reduced life expectancy. In chronic obstructive pulmonary disease, long-term oxygen therapy ameliorates pulmonary hypertension and greatly improves survival, although the correction of alveolar hypoxia and pulmonary hypertension is only partial. Advances in understanding of the regulation of vascular smooth muscle tone show that chronic vasoconstriction plays a more important part in the pathogenesis of hypoxic pulmonary hypertension than previously thought, and that structural vascular changes contribute less. Trials of existing vasodilators show that pulmonary hypertension can be ameliorated and systemic oxygen delivery improved in carefully selected patients, although systemic hypotensive effects limit the doses used. Vasoconstrictor pathways that are selective for the pulmonary circulation can be blocked to reduce hypoxic pulmonary hypertension without causing systemic hypotension, and thus provide potential targets for novel therapeutic strategies. © 2016 Elsevier Ltd.
O'Brien K.,Trinity College Dublin |
Lowry M.C.,Trinity College Dublin |
Corcoran C.,Trinity College Dublin |
Martinez V.G.,Trinity College Dublin |
And 6 more authors.
Oncotarget | Year: 2015
Exosomes (EVs) have relevance in cell-to-cell communication carrying protumorigenic factors that participate in oncogenesis and drug resistance and are proposed to have potential as self-delivery systems. Advancing on our studies of EVs in triple-negative breast cancer, here we more comprehensively analysed isogenic cell line variants and their EV populations, tissues cell line variants and their EV populations, as well as breast tumour and normal tissues. Profiling 384 miRNAs showed EV miRNA content to be highly representative of their cells of origin. miRNAs most substantially down-regulated in aggressive cells and their EVs originated from 14q32. Analysis of miR-134, the most substantially down-regulated miRNA, supported its clinical relevance in breast tumours compared to matched normal breast tissue. Functional studies indicated that miR-134 controls STAT5B which, in turn, controls Hsp90. miR-134 delivered by direct transfection into Hs578Ts(i)8 cells (in which it was greatly down-regulated) reduced STAT5B, Hsp90, and Bcl-2 levels, reduced cellular proliferation, and enhanced cisplatin-induced apoptosis. Delivery via miR-134-enriched EVs also reduced STAT5B and Hsp90, reduced cellular migration and invasion, and enhanced sensitivity to anti-Hsp90 drugs. While the differing effects achieved by transfection or EV delivery are likely to be, at least partly, due to specific amounts of miR-134 delivered by these routes, these EV-based studies identified miRNA-134 as a potential biomarker and therapeutic for breast cancer.
Newsholme P.,Conway Institute
Advances in Experimental Medicine and Biology | Year: 2010
Pancreatic β-cells are often referred to as "fuel sensors" as they continually monitor and respond to dietary nutrients, under the modulation of additional neurohormonal signals, in order to secrete insulin to best meet the needs of the organism. β-cell nutrient sensing requires metabolic activation, resulting in production of stimulus-secretion coupling signals that promote insulin biosynthesis and release. The primary stimulus for insulin secretion is glucose, and islet β-cells are particularly responsive to this important nutrient secretagogue, It is important to consider individual effects of different classes of nutrient or other physiological or pharmacological agents on metabolism and insulin secretion. However, given that β-cells are continually exposed to a complex milieu of nutrients and other circulating factors, it is important to also acknowledge and examine the interplay between glucose metabolism and that of the two other primary nutrient classes, the amino acids and fatty acids. It is the mixed nutrient sensing and outputs of glucose, amino and fatty acid metabolism that generate the metabolic coupling factors (MCFs) involved in signaling for insulin exocytosis. Primary MCFs in the β-cell include ATP, NADPH, glutamate, long chain acyl-CoA and diacylglycerol and are discussed in detail in this article. © Springer Science+Business Media B.V. 2010.