Journal articles: 'Ex vivo oxidation of albumin'

1

Tabata, Fuka, Yasuaki Wada, Satomi Kawakami, and Kazuhiro Miyaji. "Serum Albumin Redox States: More Than Oxidative Stress Biomarker." Antioxidants 10, no. 4 (March 24, 2021): 503. http://dx.doi.org/10.3390/antiox10040503.

Full text

Abstract:

Serum albumin is the most abundant circulating protein in mammals including humans. It has three isoforms according to the redox state of the free cysteine residue at position 34, named as mercaptalbumin (reduced albumin), non-mercaptalbumin-1 and -2 (oxidized albumin), respectively. The serum albumin redox state has long been viewed as a biomarker of systemic oxidative stress, as the redox state shifts to a more oxidized state in response to the severity of the pathological condition in various diseases such as liver diseases and renal failures. However, recent ex vivo studies revealed oxidized albumin per se could aggravate the pathological conditions. Furthermore, the possibility of the serum albumin redox state as a sensitive protein nutrition biomarker has also been demonstrated in a series of animal studies. A paradigm shift is thus ongoing in the research field of the serum albumin. This article provides an updated overview of analytical techniques for serum albumin redox state and its association with human health, focusing on recent findings.

APA, Harvard, Vancouver, ISO, and other styles

2

Ruiz-Perera, Lucia M., Anna L. Höving, Kazuko E. Schmidt, Sule Cenan, Max Wohllebe, Johannes F. W. Greiner, Christian Kaltschmidt, Matthias Simon, Cornelius Knabbe, and Barbara Kaltschmidt. "Neuroprotection Mediated by Human Blood Plasma in Mouse Hippocampal Slice Cultures and in Oxidatively Stressed Human Neurons." International Journal of Molecular Sciences 22, no. 17 (September 3, 2021): 9567. http://dx.doi.org/10.3390/ijms22179567.

Full text

Abstract:

Neuroprotection from oxidative stress is critical during neuronal development and maintenance but also plays a major role in the pathogenesis and potential treatment of various neurological disorders and neurodegenerative diseases. Emerging evidence in the murine system suggests neuroprotective effects of blood plasma on the aged or diseased brain. However, little is known about plasma-mediated effects on human neurons. In the present study, we demonstrate the neuroprotective effect mediated by human plasma and the most abundant plasma–protein human serum albumin against oxidative stress in glutamatergic neurons differentiated from human neural crest-derived inferior turbinate stem cells. We observed a strong neuroprotective effect of human plasma and human serum albumin against oxidative stress-induced neuronal death on the single cell level, similar to the one mediated by tumor necrosis factor alpha. Moreover, we detected neuroprotection of plasma and human serum albumin against kainic acid-induced excitatory stress in ex vivo cultured mouse hippocampal tissue slices. The present study provides deeper insights into plasma-mediated neuroprotection ultimately resulting in the development of novel therapies for a variety of neurological and, in particular, neurodegenerative diseases.

APA, Harvard, Vancouver, ISO, and other styles

3

Travagli, Valter, Iacopo Zanardi, Patrizia Bernini, Stefano Nepi, Leonardo Tenori, and Velio Bocci. "Effects of Ozone Blood Treatment on the Metabolite Profile of Human Blood." International Journal of Toxicology 29, no. 2 (March 2010): 165–74. http://dx.doi.org/10.1177/1091581809360069.

Full text

Abstract:

Metabonomic characterization of the effects caused by ozone and other stressors on normal human blood was performed. Samples of blood obtained from healthy subjects were treated ex vivo with increasing concentrations of ozone and/or with UV radiation and heat. 1H-NMR analysis of plasma samples after treatments showed the quantitative variation of some metabolites and the formation of new metabolites normally absent. Both the increment of some metabolites like formate, acetoacetate, and acetate and the decrement of pyruvate were of particular interest. Moreover, the oxidation of ascorbic acid and the transformation of uric acid into allantoin after ozonation within the therapeutic concentration range were observed. In the ozonated spectra, 2 unidentified peaks appeared at 2.82 ppm and 8.08 ppm. They are related to the direct antioxidant activity of albumin in the presence of ozone and they could be considered as specific markers of the blood ozonation.

APA, Harvard, Vancouver, ISO, and other styles

4

Ma, Qiangzhong, Yawen Wang, Agnes Shuk-Yee Lo, Erica M. Gomes, and Richard P. Junghans. "Cell Density Plays a Critical Role in Ex Vivo Expansion of T Cells for Adoptive Immunotherapy." Journal of Biomedicine and Biotechnology 2010 (2010): 1–13. http://dx.doi.org/10.1155/2010/386545.

Full text

Abstract:

The successful ex vivo expansion of a large numbers of T cells is a prerequisite for adoptive immunotherapy. In this study, we found that cell density had important effects on the process of expansion of T cells in vitro. Resting T cells were activated to expand at high cell density but failed to be activated at low cell density. Activated T cells (ATCs) expanded rapidly at high cell density but underwent apoptosis at low cell density. Our studies indicated that low-cell-density related ATC death is mediated by oxidative stress. Antioxidants N-acetylcysteine, catalase, and albumin suppressed elevated reactive oxygen species (ROS) levels in low-density cultures and protected ATCs from apoptosis. The viability of ATCs at low density was preserved by conditioned medium from high-density cultures of ATCs in which the autocrine survival factor was identified as catalase. We also found that costimulatory signal CD28 increases T cell activation at lower cell density, paralleled by an increase in catalase secretion. Our findings highlight the importance of cell density in T cell activation, proliferation, survival and apoptosis and support the importance of maintaining T cells at high density for their successful expansion in vitro.

APA, Harvard, Vancouver, ISO, and other styles

5

Vujacic-Mirski, Ksenija, Kai Bruns, Sanela Kalinovic, Matthias Oelze, Swenja Kröller-Schön, Sebastian Steven, Milos Mojovic, Bato Korac, Thomas Münzel, and Andreas Daiber. "Development of an Analytical Assay for Electrochemical Detection and Quantification of Protein-Bound 3-Nitrotyrosine in Biological Samples and Comparison with Classical, Antibody-Based Methods." Antioxidants 9, no. 5 (May 6, 2020): 388. http://dx.doi.org/10.3390/antiox9050388.

Full text

Abstract:

Reactive oxygen and nitrogen species (RONS) cause oxidative damage, which is associated with endothelial dysfunction and cardiovascular disease, but may also contribute to redox signaling. Therefore, their precise detection is important for the evaluation of disease mechanisms. Here, we compared three different methods for the detection of 3-nitrotyrosine (3-NT), a marker of nitro-oxidative stress, in biological samples. Nitrated proteins were generated by incubation with peroxynitrite or 3-morpholino sydnonimine (Sin-1) and subjected to total hydrolysis using pronase, a mixture of different proteases. The 3-NT was then separated by high performance liquid chromatography (HPLC) and quantified by electrochemical detection (ECD, CoulArray) and compared to classical methods, namely enzyme-linked immunosorbent assay (ELISA) and dot blot analysis using specific 3-NT antibodies. Calibration curves for authentic 3-NT (detection limit 10 nM) and a concentration-response pattern for 3-NT obtained from digested nitrated bovine serum albumin (BSA) were highly linear over a wide 3-NT concentration range. Also, ex vivo nitration of protein from heart, isolated mitochondria, and serum/plasma could be quantified using the HPLC/ECD method and was confirmed by LC-MS/MS. Of note, nitro-oxidative damage of mitochondria results in increased superoxide (O2•–) formation rates (measured by dihydroethidium-based HPLC assay), pointing to a self-amplification mechanism of oxidative stress. Based on our ex vivo data, the CoulArray quantification method for 3-NT seems to have some advantages regarding sensitivity and selectivity. Establishing a reliable automated HPLC assay for the routine quantification of 3-NT in biological samples of cell culture, of animal and human origin seems to be more sophisticated than expected.

APA, Harvard, Vancouver, ISO, and other styles

6

Vasanthan, T., N. Rochow, F. Mian, T. Codini, B. DeFrance, G. Fusch, S. Samiee-Zafarghandy, and C. Fusch. "LPS from bovine serum albumin drives TNF-α release during ex-vivo placenta perfusion experiments, contaminates the perfusion system but can be effectively removed by oxidative cleaning." Placenta 35, no. 12 (December 2014): 1095–98. http://dx.doi.org/10.1016/j.placenta.2014.10.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Khairallah, Maya, François Labarthe, Bertrand Bouchard, Gawiyou Danialou, Basil J. Petrof, and Christine Des Rosiers. "Profiling substrate fluxes in the isolated working mouse heart using 13C-labeled substrates: focusing on the origin and fate of pyruvate and citrate carbons." American Journal of Physiology-Heart and Circulatory Physiology 286, no. 4 (April 2004): H1461—H1470. http://dx.doi.org/10.1152/ajpheart.00942.2003.

Full text

Abstract:

The availability of genetically modified mice requires the development of methods to assess heart function and metabolism in the intact beating organ. With the use of radioactive substrates and ex vivo perfusion of the mouse heart in the working mode, previous studies have documented glucose and fatty acid oxidation pathways. This study was aimed at characterizing the metabolism of other potentially important exogenous carbohydrate sources, namely, lactate and pyruvate. This was achieved by using 13C-labeling methods. The mouse heart perfusion setup and buffer composition were optimized to reproduce conditions close to the in vivo milieu in terms of workload, cardiac functions, and substrate-hormone supply to the heart (11 mM glucose, 0.8 nM insulin, 50 μM carnitine, 1.5 mM lactate, 0.2 mM pyruvate, 5 nM epinephrine, 0.7 mM oleate, and 3% albumin). The use of three differentially 13C-labeled carbohydrates and a 13C-labeled long-chain fatty acid allowed the quantitative assessment of the metabolic origin and fate of tissue pyruvate as well as the relative contribution of substrates feeding acetyl-CoA (pyruvate and fatty acids) and oxaloacetate (pyruvate) for mitochondrial citrate synthesis. Beyond concurring with the notion that the mouse heart preferentially uses fatty acids for energy production (63.5 ± 3.9%) and regulates its fuel selection according to the Randle cycle, our study reports for the first time in the mouse heart the following findings. First, exogenous lactate is the major carbohydrate contributing to pyruvate formation (42.0 ± 2.3%). Second, lactate and pyruvate are constantly being taken up and released by the heart, supporting the concept of compartmentation of lactate and glucose metabolism. Finally, mitochondrial anaplerotic pyruvate carboxylation and citrate efflux represent 4.9 ± 1.8 and 0.8 ± 0.1%, respectively, of the citric acid cycle flux and are modulated by substrate supply. The described 13C-labeling strategy combined with an experimental setup that enables continuous monitoring of physiological parameters offers a unique model to clarify the link between metabolic alterations, cardiac dysfunction, and disease development.

APA, Harvard, Vancouver, ISO, and other styles

8

Lin, Kun-Chen, Christopher Glenn Wallace, Tsung-Cheng Yin, Pei-Hsun Sung, Kuan-Hung Chen, Hung-I. Lu, Han-Tan Chai, et al. "Shock Wave Therapy Enhances Mitochondrial Delivery into Target Cells and Protects against Acute Respiratory Distress Syndrome." Mediators of Inflammation 2018 (October 21, 2018): 1–16. http://dx.doi.org/10.1155/2018/5425346.

Full text

Abstract:

This study tested the hypothesis that shock wave therapy (SW) enhances mitochondrial uptake into the lung epithelial and parenchymal cells to attenuate lung injury from acute respiratory distress syndrome (ARDS). ARDS was induced in rats through continuous inhalation of 100% oxygen for 48 h, while SW entailed application 0.15 mJ/mm2for 200 impulses at 6 Hz per left/right lung field. In vitro and ex vivo studies showed that SW enhances mitochondrial uptake into lung epithelial and parenchyma cells (allp<0.001). Flow cytometry demonstrated that albumin levels and numbers of inflammatory cells (Ly6G+/CD14+/CD68+/CD11b/c+) in bronchoalveolar lavage fluid were the highest in untreated ARDS, were progressively reduced across SW, Mito, and SW + Mito (allp<0.0001), and were the lowest in sham controls. The same profile was also seen for fibrosis/collagen deposition, levels of biomarkers of oxidative stress (NOX-1/NOX-2/oxidized protein), inflammation (MMP-9/TNF-α/NF-κB/IL-1β/ICAM-1), apoptosis (cleaved caspase 3/PARP), fibrosis (Smad3/TGF-β), mitochondrial damage (cytosolic cytochrome c) (allp<0.0001), and DNA damage (γ-H2AX+), and numbers of parenchymal inflammatory cells (CD11+/CD14+/CD40L+/F4/80+) (p<0.0001). These results suggest that SW-assisted Mito therapy effectively protects the lung parenchyma from ARDS-induced injury.

APA, Harvard, Vancouver, ISO, and other styles

9

Sturtevant, Sarah, Alejandra Macias-Garcia, Sriram Krishnamoorthy, Arjan van der Flier, Alexandra Hicks, and Melanie Demers. "Differential Efficacy of Anti-Sickling and Anti-Inflammatory Mechanisms in a Fluorescent Intravital Microscopy Dorsal Skinfold Vaso-Occlusion Model in Sickle Cell Disease Townes Mice." Blood 134, Supplement_1 (November 13, 2019): 2264. http://dx.doi.org/10.1182/blood-2019-128922.

Full text

Abstract:

Sickle cell disease (SCD) is characterized by acute and repetitive vaso-occlusive crises (VOC). These crises have been hypothesized to occur when blood flow is reduced following obstruction of sickle-shaped red blood cells in the vasculature. However, it is now well established that inflammation, oxidative stress, endothelial activation and pro-coagulation in sickle cell disease patients also contribute to the formation of heterocellular aggregates that can lead to VOC (Vercellotti and Belcher, 2014). Transgenic SCD mice recapitulate the pathology of human disease in response to stimuli such as heme injection and hypoxia/reoxygenation. SCD SS Townes mice, which express human α and sickle γAβS globins, AA Townes mice expressing normal human α and normal γAβA globins and heterozygous AS mice which express only one allele of the γAβS sickle gene were used. To characterize vaso-occlusion in these mice and evaluate the efficacy of different pharmacological mechanisms, we modified the skinfold vaso-occlusion model (Kalambur et al, 2004) using fluorescent intravital microscopy to visualize blood flow occlusion following hemin injection or hypoxia/reoxygenation challenge. Dorsal skinfold chambers were implanted and24 hours post-surgery mice were injected with FITC-dextran for visualization of flowing blood vessels. Skinfold bearing mice were then subjected to hemin treatment (16 μmoles/kg) or hypoxia (7%; 1 hour)/reoxygenation (1 hour) followed by the injection of Alexa fluor 647-labeled albumin to allow quantification of occluded vessels through dual fluorescent image analysis. Following hemin injection, SS mice showed significant ~30% vaso-occlusion in comparison to AA mice with ~8%, whereas the AS mice showed an intermediate phenotype with ~20% vaso-occlusion. Hypoxia/reoxygenation challenge also resulted in significant vaso-occlusion for SS mice (~25%) whereas only 5% was observed in AA mice. Interestingly, AS mice also showed a significant amount of vaso-occlusion (~25%) similar to SS mice when challenged with hypoxia/reoxygenation. Although no sickling can be observed in an ex vivo sickling assay using AS red blood cells, an intermediate amount of free Hemoglobin (Hb) can be detected in the plasma of these mice and rolling can be observed. This suggests that these vaso-occlusive models relate more on the inflammatory and endothelial activation state and are independent of the sickling potential of the red blood cell. We then used our model with hypoxia/reoxygenation challenge to evaluate the effects of dimethyl fumarate (DMF, 15 mpk BID), an anti-P-Selectin antibody (150ug/mouse) and the covalent hemoglobin oxygen affinity modulator GBT-440 (300 mpk). As anti-inflammatory agents, DMF and Anti-P-Selectin significantly reduced vaso-occlusion in SS mice by ~60% compared to the vehicle treated mice, but GBT-440 did not inhibit vaso-occlusion at a dose where a significant reduction in p50 was observed. In conclusion, our data have shown that obstruction of blood flow in the skinfold vaso-occlusion model in SCD Townes mice reflects the vascular inflammatory state of the disease and is independent of the ex vivo capacity of red blood cell to sickle. Disclosures Sturtevant: Sanofi: Employment. Macias-Garcia:Sanofi: Employment. Krishnamoorthy:Sanofi: Employment. van der Flier:Sanofi: Employment. Hicks:Sanofi: Employment. Demers:Sanofi: Employment.

APA, Harvard, Vancouver, ISO, and other styles

10

Jeffs, Joshua W., Shadi Ferdosi, Hussein N. Yassine, and Chad R. Borges. "Ex vivo instability of glycated albumin: A role for autoxidative glycation." Archives of Biochemistry and Biophysics 629 (September 2017): 36–42. http://dx.doi.org/10.1016/j.abb.2017.07.004.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Czartolomna, J., N. F. Voelkel, and S. W. Chang. "Permeability characteristics of isolated perfused rat lungs." Journal of Applied Physiology 70, no. 4 (April 1, 1991): 1854–60. http://dx.doi.org/10.1152/jappl.1991.70.4.1854.

Full text

Abstract:

We examined the factors that influence the permeability characteristics of isolated perfused rat lungs and compared the ex vivo permeability-surface area product (PS) with that obtained in vivo. In lungs perfused for 20 min with homologous blood or a physiological salt solution (PSS) containing 4 g/100 ml albumin, mean PS values, obtained by the single-sample method of Kern et al. [Am. J. Physiol. 245 (Heart Circ. Physiol. 14): H229-H236, 1983], were 9.9 +/- 0.6 (SE) and 6.8 +/- 0.3 cm3.min-1.g wet lung-1.10(-2), respectively. These values were similar to lung PS obtained in intact rats (7.7 +/- 0.4 cm3.min-1.g wet lung-1.10(-2). In perfused lungs, PS values were influenced by the perfusate albumin concentration, the length of perfusion time, and the degree of vascular recruitment. Twenty minutes after lung isolation, PS was 126% higher in lungs perfused with albumin-free PSS containing Ficoll than in lungs perfused with albumin-PSS. Moreover, PS in Ficoll-PSS-perfused lungs increased even higher after 2 h of perfusion, and this time-dependent increase in PS was attenuated by addition of 0.1 g/100 ml albumin to the perfusate. Two hours of ex vivo ventilation with hypoxic (0 or 3% 0(2)) or hyperoxic (95% 0(2)) gas mixture did not affect PS values in perfused lungs. However, PS was elevated in lungs perfused ex vivo with protamine, which causes endothelial cell injury, or in lungs from rats exposed in vivo to human recombinant tumor necrosis factor.(ABSTRACT TRUNCATED AT 250 WORDS)

APA, Harvard, Vancouver, ISO, and other styles

12

Morgan, T. J., M. Vellaichamy, D. M. Cowley, S. L. Weier, B. Venkatesh, and M. A. Jonest. "Equivalent Metabolic Acidosis with Four Colloids and Saline on Ex Vivo Haemodilution." Anaesthesia and Intensive Care 37, no. 3 (May 2009): 407–14. http://dx.doi.org/10.1177/0310057x0903700304.

Full text

Abstract:

Colloid infusions can cause metabolic acidosis. Mechanisms and relative severity with different colloids are incompletely understood. We compared haemodilution acid-base effects of 4% albumin, 3.5% polygeline, 4% succinylated gelatin (all weak acid colloids, strong ion difference 12 mEq/l, 17.6 mEq/l and 34 mEq/l respectively), 6% hetastarch (non-weak acid colloid, strong ion difference zero) and 0.9% saline (crystalloid, strong ion difference zero). Gelatin weak acid properties were tracked via the strong ion gap. Four-step ex vivo dilutions of pre-oxygenated human venous blood were performed to a final [Hb] near 50% baseline. With each fluid, base excess fell to approximately −13 mEq/l. Base excess/[Hb] relationships across dilution were linear and direct (R2 ≥0.96), slopes and intercepts closely resembling saline. Baseline strong ion gap was −0.3 (2.1) mEq/l. Post-dilution increases occurred in three groups: small with saline, hetastarch and albumin (to 3.5 (02) mEq/l, 4.3 (0.3) mEq/l, 3.3 (1.4) mEq/l respectively), intermediate with polygeline (to 12.2 (0.9) mEq/l) and greatest with succinylated gelatin (to 20.8 (1.4) mEq/l). We conclude that, despite colloid weak acid activity ranging from zero (hydroxyethyl starch) to greater than that of albumin with both gelatin preparations, ex vivo dilution causes a metabolic acidosis of identical severity to saline in each case. This uniformity reflects modifications to the albumin and gelatin saline vehicles, in part aimed at pH correction. By proportionally increasing the strong ion difference, these modifications counter deviations from pure saline effects caused by colloid weak acid activity. Extrapolation in vivo requires further investigation.

APA, Harvard, Vancouver, ISO, and other styles

13

Kaul, Dhananjay K., Xiao-du Liu, Xiaoqin Zhang, Li Ma, and Ronald L. Nagel. "Antioxidants Inhibit Sickle Cell Adhesion to Activated Endothelium in an Ex Vivo Preparation." Blood 104, no. 11 (November 16, 2004): 3574. http://dx.doi.org/10.1182/blood.v104.11.3574.3574.

Full text

Abstract:

Abstract In sickle cell anemia (SS), intravascular sickling and attendant transient occlusive events are implicated in the generation of reactive oxygen species (ROS) and vascular endothelial activation. Oxidants (as well as cytokines) result in up-regulation of endothelial adhesion molecules that may lead to increased adhesion of sickle red blood cells (SS RBC) and contribute to vaso-occlusion. We hypothesize that endothelial activation will augment the expression of adhesion molecules involved in SS RBC-endothelium interaction, and that antioxidants will have an inhibitory effect on this interaction. To this end, we have tested selected antioxidants for their efficacy to inhibit SS RBC adhesion in the ex vivo mesocecum vasculature of the rat stimulated by platelet-activating factor (PAF). PAF, a potent inflammatory agent, results in endothelial ROS generation (Suematsu et al. Am. J. Physiol. 1993), as well as in increased adhesion of SS RBCs (Kaul et al. Blood, 2000). Here, we have tested the efficacy of superoxide dismutase (SOD), catalase and polynitroxylated albumin (PNA). While SOD and catalase remove superoxide (O2 ·−) and H2O2, respectively, nitroxides covalently attached to albumin (i.e., PNA) act as intra-vascular SOD mimetic and also facilitate heme-mediated catalytic removal of H2O2. To directly demonstrate the involvement of ROS (O2 •- and H2O2), the ex vivo vasculature was pre-treated with PAF (200 pg/ml in Ringer-albumin solution) followed by infusion with SOD (1500 U in 5 ml Ringer-albumin) or catalase (10,000 U in 5 ml) (each 15-min incubation). The control preparations were incubated with PAF and Ringer-albumin. For experiments involving PNA, the vasculature was first treated with PAF and followed by infusion of PNA or control human serum albumin (HSA) (each 33 mg/ml) diluted in Ringer-albumin solution (incubation 30 min). In PAF or PAF/HSA-treated preparations, infusion of SS RBCs (Hct 30 in Ringer-albumin) caused widespread adhesion of these cells exclusively in postcapillary venules. The adhesion was inversely correlated with vessel diameter, resulting in frequent blockage of small-diameter venules. In contrast, preparations treated with PAF/SOD or PAF/catalase showed a marked decrease in adhesion in venules of all diameters resulting in a significantly lower Y-intercept of the regression line as compared with the control group (p<0.00001). On the other hand, PNA caused almost complete inhibition of SS RBC adhesion in PAF-treated preparation, demonstrating even a greater anti-adhesive efficacy as evidenced by lower Y-intercept (p<0.001–0.0001 vs. SOD and catalase). The decrease in adhesion was accompanied by a significantly lower peripheral resistance (p<0.03–0.018). These results show that antioxidants inhibit SS RBC adhesion to endothelium stimulated by PAF, probably by scavenging and/or blocking PAF-generated oxidants. Thus, blockade of oxidant generation may constitute an effective therapeutic strategy to prevent SS RBC adhesion.

APA, Harvard, Vancouver, ISO, and other styles

14

Aledo, Juan C., and Pablo Aledo. "Susceptibility of Protein Methionine Oxidation in Response to Hydrogen Peroxide Treatment–Ex Vivo Versus In Vitro: A Computational Insight." Antioxidants 9, no. 10 (October 13, 2020): 987. http://dx.doi.org/10.3390/antiox9100987.

Full text

Abstract:

Methionine oxidation plays a relevant role in cell signaling. Recently, we built a database containing thousands of proteins identified as sulfoxidation targets. Using this resource, we have now developed a computational approach aimed at characterizing the oxidation of human methionyl residues. We found that proteins oxidized in both cell-free preparations (in vitro) and inside living cells (ex vivo) were enriched in methionines and intrinsically disordered regions. However, proteins oxidized ex vivo tended to be larger and less abundant than those oxidized in vitro. Another distinctive feature was their subcellular localizations. Thus, nuclear and mitochondrial proteins were preferentially oxidized ex vivo but not in vitro. The nodes corresponding with ex vivo and in vitro oxidized proteins in a network based on gene ontology terms showed an assortative mixing suggesting that ex vivo oxidized proteins shared among them molecular functions and biological processes. This was further supported by the observation that proteins from the ex vivo set were co-regulated more often than expected by chance. We also investigated the sequence environment of oxidation sites. Glutamate and aspartate were overrepresented in these environments regardless the group. In contrast, tyrosine, tryptophan and histidine were clearly avoided but only in the environments of the ex vivo sites. A hypothetical mechanism of methionine oxidation accounts for these observations presented.

APA, Harvard, Vancouver, ISO, and other styles

15

Mapanga, Rudo F., Danzil E. Joseph, Marco Saieva, Florence Boyer, Philippe Rondeau, Emmanuel Bourdon, and M. Faadiel Essop. "Glycation abolishes the cardioprotective effects of albumin during ex vivo ischemia-reperfusion." Physiological Reports 5, no. 2 (January 2017): e13107. http://dx.doi.org/10.14814/phy2.13107.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Musante, Luca, Maurizio Bruschi, Giovanni Candiano, Andrea Petretto, Nazzareno Dimasi, Piero Del Boccio, Andrea Urbani, Giovanni Rialdi, and Gian Marco Ghiggeri. "Characterization of oxidation end product of plasma albumin ‘in vivo’." Biochemical and Biophysical Research Communications 349, no. 2 (October 2006): 668–73. http://dx.doi.org/10.1016/j.bbrc.2006.08.079.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Higginson, Cody J., Marsha R. Eno, Susan Khan, Michael D. Cameron, and M. G. Finn. "Albumin-Oxanorbornadiene Conjugates Formed ex Vivo for the Extended Circulation of Hydrophilic Cargo." ACS Chemical Biology 11, no. 8 (June 27, 2016): 2320–27. http://dx.doi.org/10.1021/acschembio.6b00444.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Fabrizius-Homan, D. J., S. L. Cooper, and D. F. Mosher. "The Ex Vivo Effect of Preadsorbed Vitronectin on Platelet Activation." Thrombosis and Haemostasis 68, no. 02 (1992): 194–202. http://dx.doi.org/10.1055/s-0038-1656348.

Full text

Abstract:

SummaryThe activation of ex vivo canine platelets by preadsorbed vitronectin (VN) was sensitive not only to the polymer substrate utilized but also to the adsorption conditions employed. Lower levels of maximal platelet deposition were obtained for VN-coated silicone rubber (SR) than for other VN-coated substrates with comparable levels of adsorbed VN, but this effect was diminished with increased residence time of VN on the SR surface. Submonolayer and monolayer surface concentrations of VN elicited similar maximal levels of platelet deposition at both short (<3 h) and long (>12 h) residence times, but thrombi were larger and more dense for the submonolayer surface concentrations. VN was also more effective in forming thrombi when adsorbed sequentially before albumin instead of after albumin. To further examine these differences in the nature of adsorbed VN between substrates and adsorption conditions, sodium dodecyl sulfate (SDS) elutability measurements and Fourier transform infrared spectroscopy with attenuated total reflectance optics (FTIR-ATR) evaluations of the adsorbed protein were performed. An SDS solution was able to remove a greater percentage of the VN which was adsorbed to a submonolayer than a monolayer surface concentration when SDS displacement was initiated immediately after adsorption was terminated. However, if the adsorbed protein was allowed to reside on the surface for a length of time before the introduction of the SDS displacing media, a greater percentage of the monolayer surface concentration was removed. The submonolayer surface concentration may be better able to increase its strength of contact with the surface during the added residence time than the monolayer surface concentration. FTIR-ATR spectra of VN showed less structural alterations when it was adsorbing to SR than to a segmented polyurethane, a more thrombogenic material when coated with VN. Thus, the ability of VN to stimulate thrombus formation appeared to correlate with the percentage of VN which was nonelutable by SDS and the amount of structural alterations observed by FTIR-ATR, both of which are indications of its extent of contact with the surface.

APA, Harvard, Vancouver, ISO, and other styles

19

Uchino, S., R. Bellomo, D. Goldsmith, P. Davenport, L. Cole, I. Baldwin, S. Panagiotopoulos, P. Tipping, C. Ronco, and P. Everard. "Cytokine Removal with a Large Pore Cellulose Triacetate Filter: An Ex Vivo Study." International Journal of Artificial Organs 25, no. 1 (January 2002): 27–32. http://dx.doi.org/10.1177/039139880202500105.

Full text

Abstract:

Objective To test the hypothesis that hemofiltration using a new large pore cellulose triacetate hemofilter can achieve effective ultrafiltration of cytokines. Design Ex-vivo study. Setting Laboratory of Intensive Care Unit in tertiary hospital. Subjects Six healthy volunteers. Interventions Blood from 6 volunteers was incubated for 4 hours with 1 mg of endotoxin and then circulated through a closed hemofiltration circuit with a large pore cellulose triacetate hemofilter (nominal cut-off point: 60 kilodaltons). Hemofiltration was conducted at 1 L/h or 6 L/h of ultrafiltrate (UF) flow at the start of extra-corporeal circulation, and after 2 and 4 hours. Samples were taken from the arterial, venous and UF sampling ports. Measurements and main Results IL-Iβ, IL-6, IL-8, IL-10, TNFα, and albumin were measured. Sieving coefficients (SC) above 0.6 were achieved for IL-Iβ and IL-6 and SCs above 0.3 were achieved for IL-8 and TNF-α at 1 L/h. Sieving coefficients of all cytokines (except IL-10, p=0.22) were reduced when the ultrafiltration rate was increased from IL/h to 6 L/h (p<0.01), but the increase in ultrafiltration rate resulted in an overall increase in the clearance of all cytokines (p<0.001). The highest SC for albumin was 0.07 at 4 hours at 1 L/h, and fell to 0.01 at 6 L/h. The SCs for IL-8 fell at 4 hours (p<0.01), but the SCs for other cytokines did not change. No adsorption of cytokines and albumin was observed. Conclusion High volume hemofiltration (HVHF) using a new large pore cellulose triacetate filter achieved cytokine clearances greater than those reported with currently available hemofilters.

APA, Harvard, Vancouver, ISO, and other styles

20

Palomäki, Ari, Kimmo Malminiemi, Tiina Solakivi, and Outi Malminiemi. "Ubiquinone supplementation during lovastatin treatment: effect on LDL oxidation ex vivo." Journal of Lipid Research 39, no. 7 (July 1998): 1430–37. http://dx.doi.org/10.1016/s0022-2275(20)32524-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Migliaccio, Giovanni, Massimo Sanchez, Francesca Masiello, Valentina Tirelli, Lilian Varricchio, Carolyn Whitsett, and Anna Rita Migliaccio. "Humanized Culture Medium for Clinical Expansion of Human Erythroblasts." Cell Transplantation 19, no. 4 (April 2010): 453–69. http://dx.doi.org/10.3727/096368909x485049.

Full text

Abstract:

Ex vivo-generated erythroblasts represent alternative transfusion products. However, inclusion of bovine components in media used for their growth precludes clinical use, highlighting the importance of developing culture media based on pharmaceutical grade reagents. In addition, because adult blood generates ex vivo lower numbers of erythroblasts than cord blood, cord blood has been proposed as the source of choice for ex vivo erythroblast production. To clarify the potential of adult blood to generate erythroblasts ex vivo, experiments were designed to identify growth factors [stem cell factor (SCF), interleukin-3 (IL-3), erythropoietin (EPO), and/or thrombopoietin (TPO)] and the optimal concentration and addition schedule of hormones (dexamethasone and estradiol) sustaining maximal erythroid amplification from adult blood mononuclear cells (MNC) using media with serum previously defined as human erythroid massive amplification culture (HEMAser). Adult MNC stimulated with SCF and IL-3 in combination with EPO generated a 6–12-fold increase in erythroid cells while TPO was ineffective. Dexamethasone and estradiol (both at 10−6 M) exerted partially overlapping but nonredundant functions. Dexamethasone was indispensable in the first 10 days of culture while estradiol was required from day 10 on. The growth factor and hormone combinations identified in HEMAser were then used to formulate a media composed of dialyzed pharmaceutical grade human albumin, human albumin-lipid liposomes, and iron-saturated recombinant human tranferrin (HEMAdef). HEMAdef sustained erythroid amplification as efficiently as HEMAser for cord blood MNC and 10-fold higher than HEMAser for adult blood MNC. In fact, the numbers of erythroblasts generated in HEMAdef by adult MNC were similar to those generated by cord blood MNC. In conclusion, this study identifies growth factors, hormone combinations, and human protein-based media that allow similar levels of ex vivo erythroid expansion from adult and cord blood MNC, paving the way to evaluate adult blood as a source of ex vivo-expanded erythroblasts for transfusion.

APA, Harvard, Vancouver, ISO, and other styles

22

Whitson, B. A., E. Eren, E. Beal, D. Hayes Jr, A. F. Palmer, and S. M. Black. "Polymerized Human Serum Albumin as an Osmotic Molecule to Support Ex-Vivo Lung Perfusion." Journal of Heart and Lung Transplantation 35, no. 4 (April 2016): S178. http://dx.doi.org/10.1016/j.healun.2016.01.494.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Smith, S. F., T. D. Tetley, A. K. Datta, T. Smith, A. Guz, and R. J. Flower. "Lipocortin-1 distribution in bronchoalveolar lavage from healthy human lung: effect of prednisolone." Journal of Applied Physiology 79, no. 1 (July 1, 1995): 121–28. http://dx.doi.org/10.1152/jappl.1995.79.1.121.

Full text

Abstract:

Lipocortin-1 (LC-1; annexin-1) may mediate some anti-inflammatory actions of the glucocorticoids, probably after binding to specific cell surface binding sites. We have quantified LC-1 levels in bronchoalveolar lavage (BAL) fluid and cells collected from seven healthy volunteers before and after 7 days of treatment with an oral glucocorticoid, prednisolone (30 mg/day). Extracellular BAL LC-1 was higher and cellular LC-1 was lower after prednisolone than before [extracellular: before, median 98 ng/mg albumin (range 48–350 ng/mg albumin); after, 236 ng/mg albumin (19–414 ng/mg albumin); P < 0.05. Cellular: before, 23.3 ng/10(6) cells (14.6–26.9 ng/10(6) cells); after, 18.0 ng/10(6) cells (122–268 ng/10(6) cells); P < 0.05]. The distribution of LC-1 within BAL cells ex vivo (cell surface = 25%, cytosol = 50%, membrane = 25%) was unaffected by prednisolone treatment. However, in adherent cells that had been cultured for 4 h, 70–80% of the LC-1 was on the cell surface. In summary, prednisolone appears to promote cellular release of LC-1. The difference in distribution of cellular LC-1 in BAL cells ex vivo and in vitro may reflect adherence and/or activation.

APA, Harvard, Vancouver, ISO, and other styles

24

Crawford, R. S., S. R. Mudaliar, R. R. Henry, and A. Chait. "Inhibition of LDL oxidation in vitro but not ex vivo by troglitazone." Diabetes 48, no. 4 (April 1, 1999): 783–90. http://dx.doi.org/10.2337/diabetes.48.4.783.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Liu, Xinquan, Rashmi P. Mohanty, Esther Y. Maier, Xiujuan Peng, Steven Wulfe, Agnieszka P. Looney, Kyaw L. Aung, and Debadyuti Ghosh. "Controlled loading of albumin-drug conjugates ex vivo for enhanced drug delivery and antitumor efficacy." Journal of Controlled Release 328 (December 2020): 1–12. http://dx.doi.org/10.1016/j.jconrel.2020.08.015.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Altomare, Alessandra, Giovanna Baron, Marta Balbinot, Alessandro Pedretti, Beatrice Zoanni, Maura Brioschi, Piergiuseppe Agostoni, Marina Carini, Cristina Banfi, and Giancarlo Aldini. "In-Depth AGE and ALE Profiling of Human Albumin in Heart Failure: Ex Vivo Studies." Antioxidants 10, no. 3 (February 27, 2021): 358. http://dx.doi.org/10.3390/antiox10030358.

Full text

Abstract:

Advanced glycation end-products (AGEs) and advanced lipoxidation end-products (ALEs), particularly carboxymethyl-lysine (CML), have been largely proposed as factors involved in the establishment and progression of heart failure (HF). Despite this evidence, the current literature lacks the comprehensive identification and characterization of the plasma AGEs/ALEs involved in HF (untargeted approach). This work provides the first ex vivo high-resolution mass spectrometry (HR-MS) profiling of AGEs/ALEs occurring in human serum albumin (HSA), the most abundant protein in plasma, characterized by several nucleophilic sites and thus representing the main protein substrate for AGE/ALE formation. A set of AGE/ALE adducts in pooled HF-HSA samples was defined, and a semi-quantitative analysis was carried out in order to finally select those presenting in increased amounts in the HF samples with respect to the control condition. These adducts were statistically confirmed by monitoring their content in individual HF samples by applying a targeted approach. Selected AGEs/ALEs proved to be mostly CML derivatives on Lys residues (i.e., CML-Lys12, CML-Lys378, CML-Lys402), and one deoxy-fructosyl derivative on the Lys 389 (DFK-Lys 389). The nature of CML adducts was finally confirmed using immunological methods and in vitro production of such adducts further confirmed by mass spectrometry.

APA, Harvard, Vancouver, ISO, and other styles

27

Kuetting, Fabian, Alois Martin Sprinkart, Anton Faron, Lisa Meffert, Christian Jansen, Julian Luetkens, Ulrike Attenberger, and Daniel Kuetting. "Identification of malignant ascites using MR-based T1 mapping." Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020): e16719-e16719. http://dx.doi.org/10.1200/jco.2020.38.15_suppl.e16719.

Full text

Abstract:

e16719 Background: Non-invasive identification of malignant ascites is a challenge in clinical practice.Thus, we decided to assess if an MR-based T1 mapping approach allows non-invasive differentiation of malignant and non-malignant effusions. Methods: In-vitro and ex-vivo MR-examinations were performed on a clinical 1.5T MR-system. T1 mapping was performed with spectroscopy and an adapted modified Look-Locker inversion-recovery (MOLLI) acquisition. For in-vitro experiments 13 titrated solutions with varying albumin content (0 to 200 g/l) were examined. For ex-vivo evaluation 27 ascites/pleural effusion samples from patients with malignancy (19 with histologic tumor confirmation in effusion) and 18 samples from patients without malignancy were examined. All samples underwent histological and laboratory testing. Samples were classified as malignant-positive histology, malignant-negative histology and non-malignant negative histology. Lab values were correlated with T1 maps and receiver operating characteristic (ROC) analysis was used to determine the optimal T1-value threshold to differentiate malignant and non-malignant ascites. Results: In in-vitro analysis both methods showed a high correlation with albumin-content (MOLLI: r = -0.97; Spectroscopy: -0.98). T1-values derived from the reference standard (Spectroscopy) and the MOLLI technique had a high agreement (intraclass correlation single measures: 0,9889, 95% CI: 0,52 to 0,99; average measures: 9,994, 95% CI 0,69 to 0,99). Bland-Altman analysis showed a strong agreement between both methods: 62.5 ± 35 (95% CI: 41.2 to 83.8) Ex-vivo analysis revealed significant differences between T1 values from patients with malignant+ histology (median: 2237; IQR: 2132 to 2327.5) and patients with non malignant- negative histology (median: 2611; IQR: 2548 to 2803, p < 0.0001) as well as between malignant+ histology and all other included patients (median: 2585; IQR: 2503 to 2710, p < 0.0001) Multiple regression analysis of in-vivo results revealed that only albumin content correlated with MOLLI based T1 measurements (p < 0.0001; r = -0.65) ROC analysis for differentiation between malignant and non-malignant effusions (malignant+ histology vs. all other) showed an AUC of 0.897; 95% CI: 0.769 to 0.967). Malignant+ histology vs. non-malignant- histology showed an AUC of 1.000 (cut off Lolli > 2419; 95% CI: 0.905 to 1). Conclusions: T1 Mapping shows excellent correlation with protein content of fluids.MR- T1 mapping allows for non-invasive differentiation of malignant and non-malignant effusions in an ex-vivo set up.

APA, Harvard, Vancouver, ISO, and other styles

28

Ceccaldi, Pierre-Francois, Laurent Gavard, Laurent Mandelbrot, Elisabeth Rey, Robert Farinotti, Jean-Marc Treluyer, and Sophie Gil. "Functional Role of P-Glycoprotein and Binding Protein Effect on the Placental Transfer of Lopinavir/Ritonavir in the Ex Vivo Human Perfusion Model." Obstetrics and Gynecology International 2009 (2009): 1–6. http://dx.doi.org/10.1155/2009/726593.

Full text

Abstract:

Aims. To study the influence of P-glycoprotein (P-glycoprotein, ABCB1, MDR1) function on placental transfer of lopinavir with ritonavir at different albumin concentrations.Methods. Cotyledons were perfused with lopinavir, ritonavir, and the internal control antipyrin, at various albumin concentrations (10, 30, 40 g/L). After the control phase of each experiment, the P-glycoprotein inhibitor ciclosporin A was added at middle perfusion (45 minutes). Fetal Transfer Rate (FTR) and Clearance Index (CLI) were compared between the 2 phases.Results. In the control phase, the clearance index of lopinavir decreased from 0.401±0.058 to 0.007±0.027, as albumin concentrations increased from 10 g/L to higher concentrations (30, 40 g/L). When adding ciclosporin A at physiological albumin concentrations, the clearance index of lopinavir increased significantly 10.3 fold (95% of CI difference [−0.156,−0.002],P=.046) and became positive for ritonavir.Conclusions. Even at high albumin concentrations, inhibition of placental P-glycoprotein increased placental transfer of lopinavir, suggesting that this efflux pump actively reduces placental transfer of the drug. This mechanism may play a role in fetal exposure to maternal antiretroviral therapy.

APA, Harvard, Vancouver, ISO, and other styles

29

Di Gioia, Sante, Joanna Rejman, Salvatore Carrabino, Ida De Fino, Carsten Rudolph, Ann Doherty, Laura Hyndman, et al. "Role of Biophysical Parameters on ex Vivo and in Vivo Gene Transfer to the Airway Epithelium by Polyethylenimine/Albumin Complexes." Biomacromolecules 9, no. 3 (March 2008): 859–66. http://dx.doi.org/10.1021/bm701190p.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Badiou, Cristol, Morena, Bosc, Carbonneau, Dupuy, Descomps, and Canaud. "Vitamin E Supplementation Increases LDL Resistance to ex vivo Oxidation in Hemodialysis Patients." International Journal for Vitamin and Nutrition Research 73, no. 4 (July 1, 2003): 290–96. http://dx.doi.org/10.1024/0300-9831.73.4.290.

Full text

Abstract:

Background: Oxidative stress and alterations in lipid metabolism observed in hemodialysis patients potentiate the low-density lipoprotein (LDL) oxidability, recognized as a key event during early atherogenesis. Objective: To explore the effects of an oral vitamin E supplementation on oxidative stress markers and LDL oxidability in hemodialysis patients. Methods: Fourteen hemodialysis patients and six healthy volunteers were given oral vitamin E (500 mg/day) for six months. Oxidative stress was assessed using: plasma and lipoprotein vitamin E levels [high-performance liquid chromatography (HPLC) procedure]; thiobarbituric acid reactive substances (TBARS, Yaggi method); and copper-induced LDL oxidation. All parameters were evaluated before initiation of vitamin E supplementation, and at three and six months thereafter. Results: At baseline, a significantly higher TBARS concentration and a higher LDL oxidability were observed in hemodialysis patients when compared to controls. After six months of vitamin E supplementation, TBARS and LDL oxidability were normalized in hemodialysis patients. Conclusion: Our data confirm that hemodialysis patients are exposed to oxidative stress and increased susceptibility to ex vivo LDL oxidation. Since oral vitamin E supplementation prevents oxidative stress and significantly increases LDL resistance to ex vivo oxidation, supplementation by natural antioxidants such as vitamin E may be beneficial in hemodialysis patients.

APA, Harvard, Vancouver, ISO, and other styles

31

de Gordoa, Juan Carlos Ruiz, Mertxe de Renobales, Ana del Cerro, Eva Fernández de Labastida, Pilar Amiano, and Miren Dorronsoro. "Habitual fish intake is associated with decreased LDL susceptibility to ex vivo oxidation." Lipids 37, no. 4 (April 2002): 333–41. http://dx.doi.org/10.1007/s11745-002-0900-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Maheshwari, Vaibhav, Xia Tao, Stephan Thijssen, and Peter Kotanko. "Removal of Protein-Bound Uremic Toxins Using Binding Competitors in Hemodialysis: A Narrative Review." Toxins 13, no. 9 (September 4, 2021): 622. http://dx.doi.org/10.3390/toxins13090622.

Full text

Abstract:

Removal of protein-bound uremic toxins (PBUTs) during conventional dialysis is insufficient. PBUTs are associated with comorbidities and mortality in dialysis patients. Albumin is the primary carrier for PBUTs and only a small free fraction of PBUTs are dialyzable. In the past, we proposed a novel method where a binding competitor is infused upstream of a dialyzer into an extracorporeal circuit. The competitor competes with PBUTs for their binding sites on albumin and increases the free PBUT fraction. Essentially, binding competitor-augmented hemodialysis is a reactive membrane separation technique and is a paradigm shift from conventional dialysis therapies. The proposed method has been tested in silico, ex vivo, and in vivo, and has proven to be very effective in all scenarios. In an ex vivo study and a proof-of-concept clinical study with 18 patients, ibuprofen was used as a binding competitor; however, chronic ibuprofen infusion may affect residual kidney function. Binding competition with free fatty acids significantly improved PBUT removal in pre-clinical rat models. Based on in silico analysis, tryptophan can also be used as a binding competitor; importantly, fatty acids or tryptophan may have salutary effects in HD patients. More chemoinformatics research, pre-clinical, and clinical studies are required to identify ideal binding competitors before routine clinical use.

APA, Harvard, Vancouver, ISO, and other styles

33

Benito, Sonia, Susana Buxaderas, and M. Teresa Mitjavila. "Flavonoid metabolites and susceptibility of rat lipoproteins to oxidation." American Journal of Physiology-Heart and Circulatory Physiology 287, no. 6 (December 2004): H2819—H2824. http://dx.doi.org/10.1152/ajpheart.00471.2004.

Full text

Abstract:

Flavonoids are ingested with vegetables and beverages and exert a beneficial effect on cardiovascular disease. Studies in animals in vitro and in humans ex vivo on the resistance of lipoproteins to oxidation are not consistent and the mechanisms by which flavonoids protect against atherosclerosis are a matter of debate. In the present study, we investigated the effects of administering diets containing 0.3% (wt/wt) quercetin, 0.3% (wt/wt) catechin, or 35% (vol/wt) dealcoholated red wine (DRW) for 10 days in healthy rats on markers of oxidative damage in lipoproteins and in plasma. The antioxidant levels in low-density lipoproteins (LDL) or the lag phase, oxidation rate, and maximum level of conjugated dienes during ex vivo LDL oxidation did not differ between control and treated rats. Plasma levels of α-tocopherol and retinol were similar in all groups. The total antioxidant status of the plasma from rats fed either quercetin or DRW diet was higher than in control rats. Only glucuronide and sulfate compounds of quercetin were detected in plasma from rats fed the quercetin-rich diet, and no flavonoids or their metabolites were detected in plasma or LDL from rats fed the catechin- or the DRW-rich diet. No significant differences in malondialdehyde or in conjugated dienes in plasma were observed. These results indicate that although metabolites from quercetin are present in plasma, they are not detected in lipoproteins and do not modify the level of other antioxidants. In conclusion, in the absence of any pathology or of oxidative stress the intake of quercetin, catechin, or DRW did not protect lipoproteins from oxidation ex vivo.

APA, Harvard, Vancouver, ISO, and other styles

34

Sakuma, Tsutomu, Chiharu Tuchihara, Masanobu Ishigaki, Kazuhiro Osanai, Yoshihiro Nambu, Hirohisa Toga, Keiji Takahashi, Nobuo Ohya, Takayuki Kurihara, and Michael A. Matthay. "Denopamine, a β1-adrenergic agonist, increases alveolar fluid clearance in ex vivo rat and guinea pig lungs." Journal of Applied Physiology 90, no. 1 (January 1, 2001): 10–16. http://dx.doi.org/10.1152/jappl.2001.90.1.10.

Full text

Abstract:

The effect of denopamine, a selective β1-adrenergic agonist, on alveolar fluid clearance was determined in both ex vivo rat and guinea pig lungs. Alveolar fluid clearance was measured by the progressive increase in the concentration of Evans blue-labeled albumin over 1 h at 37°C. Denopamine (10−6 to 10−3 M) increased alveolar fluid clearance in a dose-dependent manner in ex vivo rat lungs. Denopamine also stimulated alveolar fluid clearance in guinea pig lungs. Atenolol, a selective β1-adrenergic antagonist, and amiloride, a sodium channel inhibitor, inhibited denopamine-stimulated alveolar fluid clearance. The potency of denopamine was similar to that of similar doses of isoproterenol or terbutaline. Short-term hypoxia (100% nitrogen for 1–2 h) did not alter the stimulatory effect of denopamine. Denopamine (10−4, 10−3 M) increased intracellular adenosine 3′,5′-cyclic monophosphate levels in cultured rat alveolar type II cells. In summary, denopamine, a selective β1-adrenergic agonist, stimulates alveolar fluid clearance in both ex vivo rat and guinea pig lungs.

APA, Harvard, Vancouver, ISO, and other styles

35

Pekov, S. I., A. A. Sorokin, A. A. Kuzin, K. V. Bocharov, D. S. Bormotov, A. S. Shivalin, V. A. Shurkhay, A. A. Potapov, E. N. Nikolaev, and I. A. Popov. "Analysis of phosphatidylcholines alterations in human glioblastoma multiform tissues ex vivo." Biomeditsinskaya Khimiya 67, no. 1 (January 2021): 81–87. http://dx.doi.org/10.18097/pbmc20216701081.

Full text

Abstract:

Significant metabolism alteration is accompanying the cell malignization process. Energy metabolism disturbance leads to the activation of de novo synthesis and beta-oxidation processes of lipids and fatty acids in a cancer cell, which becomes an indicator of pathological processes inside the cell. The majority of studies dealing with lipid metabolism alterations in glial tumors are performed using the cell lines in vitro or animal models. However, such conditions do not entirely represent the physiological conditions of cell growth or possible cells natural variability. This work presents the results of the data obtained by applying ambient mass spectrometry to human glioblastoma multiform tissues. By analyzing a relatively large cohort of primary and secondary glioblastoma samples, we identify the alterations in cells lipid composition, which accompanied the development of grade IV brain tumors. We demonstrate that primary glioblastomas, as well as ones developed from astrocytomas, are enriched with mono- and diunsaturated phosphatidylcholines (PC 26:1, 30:2, 32:1, 32:2, 34:1, 34:2). Simultaneously, the saturated and polyunsaturated phosphatidylcholines and phosphatidylethanolamines decrease. These alterations are obviously linked to the availability of the polyunsaturated fatty acids and activation of the de novo lipid synthesis and beta-oxidation pathways under the anaerobic conditions in the tumor core.

APA, Harvard, Vancouver, ISO, and other styles

36

Mocan, Lucian, Cristian Matea, Flaviu A. Tabaran, Ofelia Mosteanu, Teodora Pop, Cosmin Puia, Lucia Agoston-Coldea, et al. "Selective ex vivo photothermal nano-therapy of solid liver tumors mediated by albumin conjugated gold nanoparticles." Biomaterials 119 (March 2017): 33–42. http://dx.doi.org/10.1016/j.biomaterials.2016.12.009.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Rohiwal, S. S., A. P. Tiwari, G. Verma, and S. H. Pawar. "Preparation and evaluation of bovine serum albumin nanoparticles for ex vivo colloidal stability in biological media." Colloids and Surfaces A: Physicochemical and Engineering Aspects 480 (September 2015): 28–37. http://dx.doi.org/10.1016/j.colsurfa.2015.04.017.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Hnat, Michael, and Roger E. Bawdon. "Transfer of Meropenem in the ex Vivo Human Placenta perfusion Model." Infectious Diseases in Obstetrics and Gynecology 13, no. 4 (2005): 223–27. http://dx.doi.org/10.1155/2005/961356.

Full text

Abstract:

Objectives.To determine maternal-fetal transplacental passage of meropenem in the ex vivo human perfusion model.Study design.Term placentae (n= 6) were collected immediately after delivery. A single cotyledon was localized, perfused and stabilized with physiologic Eagles minimal essential medium containing 3% bovine albumin and heparin as described by Chalier (Chalier JC. Criteria for evaluating perfusion experiments and presentation results. Contrib Gynecol Obstet 1985; 13:32–39). Meropenem was added to the maternal medium in concentrations similar to maternal serum peak and trough levels, then perfused through the maternal circulation of the cotyledon. To assess transfer and accumulation, fluid aliquots from both the maternal and fetal compartments were collected over an hour at defined intervals in an open and closed system. AntipyrineC14was added to the medium in order to calculate the transport fraction and clearance indexes. Meropenem and antipyrineC14concentrations were determined by High-pressure Liquid Chromatography and liquid scintillation, respectively.Results.Mean antipyrine transport fraction was 2.33 + 0.25. Maternal and fetal mean meropenem peak concentrations were 54.3 + 3.3μg/ml and 2.2 + 0.18μg/ml, respectively. Whereas, maternal and fetal mean trough concentrations were 12.7 + 1.3μg/ml and 0.41 + 0.10μg/ml, respectively. Mean peak clearance index was 0.077 + 0.007 and the mean trough was 0.052 + 0.015. Mean accumulation for the peak and trough concentrations of meropenem were 0.9 and 2.95μg/ml, respectively.Conclusions.Transplacental passage of meropenem was incomplete in the ex vivo human placental perfusion model. Accumulation was also noted in the fetal compartment

APA, Harvard, Vancouver, ISO, and other styles

39

Nui, A., T. Katsuramaki, H. Kikuchi, K. Kukita, M. Nagayama, M. Meguro, H. Kimura, M. Isobe, and K. Hirata. "Successful ex Vivo Normothermic Liver Perfusion with Purely Artificial Products using Artificial Blood." International Journal of Artificial Organs 26, no. 1 (January 2003): 46–52. http://dx.doi.org/10.1177/039139880302600108.

Full text

Abstract:

We tried to make an ex vivo functioning liver with an artificial perfusate that consisted of artificial blood in the pig liver. A liver graft from a female pig weighing 20 kg was harvested in the usual manner. The perfusion solution consisted of artificial blood, L-15 medium, distilled water, bovine serum albumin, NaHCO3, NaOH, KCl, human regular insulin, 50% glucose solution, and dexamethasone. The isolated liver was perfused with this oxygenated perfusate through the portal vein at a rate of 300 ml/min for 9 hours. Seven livers were perfused for 9 hours in this system. Five of the livers showed mean oxygen consumption of over 8 ml-02/min during perfusion. Histological findings showed that the hepatic architecture was almost completely preserved and numerous hepatocytes exhibited PAS-positive cytoplasmic glycogen deposits in these livers. These observations indicate that we have succeeded in developing an ex vivo functioning liver with an artificial perfusate employing artificial blood.

APA, Harvard, Vancouver, ISO, and other styles

40

Pool, Merel B. F., Tim L. Hamelink, Harry van Goor, Marius C. van den Heuvel, Henri G. D. Leuvenink, and Cyril Moers. "Prolonged ex-vivo normothermic kidney perfusion: The impact of perfusate composition." PLOS ONE 16, no. 5 (May 18, 2021): e0251595. http://dx.doi.org/10.1371/journal.pone.0251595.

Full text

Abstract:

Normothermic machine perfusion (NMP) of donor kidneys provides the opportunity for improved graft preservation and objective pre-transplant ex-vivo organ assessment. Currently, a multitude of perfusion solutions exist for renal NMP. This study aimed to evaluate four different perfusion solutions side-by-side and determine the influence of different perfusate compositions on measured renal perfusion parameters. Porcine kidneys and blood were obtained from a slaughterhouse. Kidneys underwent NMP at 37°C for 7 hours, with 4 different perfusion solutions (n = 5 per group). Group 1 consisted of red blood cells (RBCs) and a perfusion solution based on Williams’ Medium E. Group 2 consisted of RBCs, albumin and a balanced electrolyte composition. Group 3 contained RBCs and a medium based on a British clinical NMP solution. Group 4 contained RBCs and a medium used in 24-hour perfusion experiments. NMP flow patterns for solutions 1 and 2 were similar, solutions 3 and 4 showed lower but more stable flow rates. Thiobarbituric acid reactive substances were significantly higher in solution 1 and 4 compared to the other groups. Levels of injury marker N-acetyl-β-D glucosaminidase were significantly lower in solution 2 in comparison with solution 3 and 4. This study illustrates that the perfusate composition during NMP significantly impacts the measured perfusion and injury parameters and thus affects the interpretation of potential viability markers. Further research is required to investigate the individual influences of principal perfusate components to determine the most optimal conditions during NMP and eventually develop universal organ assessment criteria.

APA, Harvard, Vancouver, ISO, and other styles

41

Kim, H., S. Kim, D. Kang, H. Yong, S. Lee, J. Jeong, and Y. Choi. "Intraoperative sentinel lymph node identification using novel receptor binding agent (technetium-99m neomannosyl human serum albumin, 99mTc-MSA) in stage I non-small cell lung cancer." Journal of Clinical Oncology 27, no. 15_suppl (May 20, 2009): 7588. http://dx.doi.org/10.1200/jco.2009.27.15_suppl.7588.

Full text

Abstract:

7588 Background: In order to simplify synthesis and labelling procedures and to improve the biological properties, we developed a novel mannose receptor-binding agent, Technetium-99m neomannosyl human serum albumin (99mTc-MSA). This study was designed to test the reliability and feasibility of sentinel nodes identification using this new radioactive agent in stage I non-small cell lung cancer. Methods: A total dose of 1mCi of 99mTc- MSA in 0.2ml was administered in one shot at the peri-tumoral region under the chest CT or bronchoscope guidance 3 hours before surgery in the CT room. Dynamic whole-body SPECT lymphoscintigraphic image was obtained at 30 min after injection and static thoracic SPECT lymphoscintigraphy images were acquired at 1 and 2 hour after injection. During operation, the radioactivity of the lymph nodes was counted with a handheld gamma probe before (in vivo) and after (ex vivo) dissection. Lymph nodes with an ex vivo radioactive count more than 5 times the radioactivity count of the resected lung tissue were identified as sentinel nodes. The correlation between the in vivo and ex vivo results was examined. All harvested lymph nodes were examined histologically. Results: Thirty patients (20 men, 10 women; mean age, 62.6±9.40 years) who were candidates for lobectomy with mediastinal lymph node dissection for stage I non-small cell lung cancer were enrolled consecutively. Sentinel nodes could be detected from 30 minutes to 5 hours after the injection of 99mTc-MSA on lymphoscintigraphy. The mean number of dissected lymph nodes per patients was 20.7±1.30 (8∼41). Among 30 patients, sentinel lymph nodes could be identified in all patients (100%). The mean number of sentinel lymph nodes identified was 2.4±1.04 stations (range, 1∼5) per patient. No false-negative sentinel lymph nodes were detected in any of the 8 patients with N1 or N2 disease (0%). The relationship between in vivo and ex vivo results for mediastinal sentinel lymph nodes showed concurrence in 25 of 30 patients (83.3%). Conclusions: The results of this clinical trial showed that 99mTc-MSA had promising properties for sentinel nodes identification in non-small cell lung cancer. No significant financial relationships to disclose.

APA, Harvard, Vancouver, ISO, and other styles

42

Dumkliang, Ekachai, Tanasait Ngawhirunpat, Theerasak Rojanarata, Prasopchai Patrojanasophon, Boonnada Pamornpathomkul, and Praneet Opanasopit. "Preparation and Evaluation of 6-Maleimidohexanoic Acid Grafted Chitosan Nanoparticles as a Novel Carrier for Intranasal Protein Delivery." Key Engineering Materials 859 (August 2020): 214–19. http://dx.doi.org/10.4028/www.scientific.net/kem.859.214.

Full text

Abstract:

In this study, 6-maleimidohexanoic acid grafted chitosan nanoparticles (MHA-CS NPs) were prepared and evaluated the efficiency of intranasal protein delivery as compared with well-known chitosan nanoparticles (CS NPs). Fluorescein isothiocyanate labelled with bovine serum albumin (FITC-BSA) was used as a model protein. The results indicated that both CS NPs and MHA-CS NPs were positively charged NPs before and after protein loading. The condition for optimal protein loading was 1:6 mass ratio of protein/NPs at 1 h incubation period. The optimal formulations of CS NPs and MHA-CS NPs were evaluated on porcine mucosa as ex vivo. The mucoadhesive and permeation properties of FITC-BSA loaded MHA-CS NPs showed a greater than FITC-BSA loaded CS NPs and FITC-BSA solution, respectively. These ex vivo studies present the potential of MHA-CS NPs as a novel carrier for intranasal protein delivery that will be a candidate for in vivo study.

APA, Harvard, Vancouver, ISO, and other styles

43

Dixon, Brian M., Shi-Hua D. Heath, Robert Kim, Jung H. Suh, and Tory M. Hagen. "Assessment of Endoplasmic Reticulum Glutathione Redox Status Is Confounded by Extensive Ex Vivo Oxidation." Antioxidants & Redox Signaling 10, no. 5 (May 2008): 963–72. http://dx.doi.org/10.1089/ars.2007.1869.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Liu, Wei, Huiyong Yin, Yoko Ogawa Akazawa, Yasukazu Yoshida, Etsuo Niki, and Ned A. Porter. "Ex Vivo Oxidation in Tissue and Plasma Assays of Hydroxyoctadecadienoates:Z,E/E,EStereoisomer Ratios." Chemical Research in Toxicology 23, no. 5 (May 17, 2010): 986–95. http://dx.doi.org/10.1021/tx1000943.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Wauquier, Fabien, Audrey Daneault, Henri Granel, Janne Prawitt, Véronique Fabien Soulé, Juliette Berger, Bruno Pereira, et al. "Human Enriched Serum Following Hydrolysed Collagen Absorption Modulates Bone Cell Activity: from Bedside to Bench and Vice Versa." Nutrients 11, no. 6 (May 31, 2019): 1249. http://dx.doi.org/10.3390/nu11061249.

Full text

Abstract:

Collagen proteins are crucial components of the bone matrix. Since collagen-derived products are widely used in the food and supplement industry, one may raise the question whether collagen-enriched diets can provide benefits for the skeleton. In this study, we designed an innovative approach to investigate this question taking into account the metabolites that are formed by the digestive tract and appear in the circulation after ingestion of hydrolysed collagen. Blood samples collected in clinical and pre-clinical trials following ingestion and absorption of hydrolysed collagen were processed and applied on bone-related primary cell cultures. This original ex vivo methodology revealed that hydrolysed collagen-enriched serum had a direct impact on the behaviour of cells from both human and mouse origin that was not observed with controls (bovine serum albumin or hydrolysed casein-enriched serum). These ex vivo findings were fully in line with in vivo results obtained from a mouse model of post-menopausal osteoporosis. A significant reduction of bone loss was observed in mice supplemented with hydrolysed collagen compared to a control protein. Both the modulation of osteoblast and osteoclast activity observed upon incubation with human or mouse serum ex vivo and the attenuation of bone loss in vivo, clearly indicates that the benefits of hydrolysed collagen for osteoporosis prevention go beyond the effect of a simple protein supplementation.

APA, Harvard, Vancouver, ISO, and other styles

46

Migliaccio, Giovanni, Massimo Sanchez, Francesca Masiello, Valentina Tirelli, Lilian Varricchio, Barbara Ghinassi, Carolyn Whitsett, and Anna Rita Migliaccio. "the γ Isoform of the Glucocorticoid Receptor Is Ontogenetically Activated and Predicts Poor Ex-Vivo Expansion of Erythroid Cells From Adult Blood." Blood 114, no. 22 (November 20, 2009): 642. http://dx.doi.org/10.1182/blood.v114.22.642.642.

Full text

Abstract:

Abstract Abstract 642 Ex-vivo generated erythroblasts (EBs) represent alternative transfusion products. Adult blood (AB) contains numbers of progenitor cells comparable to those present in cord blood (CB) (106 vs 1.8×106 CD34pos cells in average AB and CB donations) but generates lower numbers of erythroblasts (EBs) (∼4.8×108 vs 6.6×1010, respectively) and, in spite of its numerous advantages, is not considered suitable for ex-vivo EB production. To assess the potential of AB to generate EBs ex-vivo, the growth factors [stem cell factor (SCF), interleukin-3 (IL-3) and erythropoietin (EPO)] and optimal concentration and addition schedule of dexamethasone (DXM) and estradiol (ES) sustaining maximal EB amplification from AB mononuclear cells (MNC) were defined using media with serum previously defined as human erythroid massive amplification culture (HEMAser). Adult MNC stimulated with SCF and IL-3 in combination with EPO generated low numbers (fold increase ∼2) of EBs at all stages of maturation. Concentration response studies conducted on MNC from 10 different donors, indicated that the further addition to the cultures of DXM and ES (both at 10-6 M) increased (∼6-12-fold) the numbers of EBs generated. Delayed addition and withdrawal experiments indicated that DXM and ES exerted partially overlapping but non-redundant functions. DXM was indispensable to achieve maximal amplification in the first 10 days of culture while ES was required from day 10 on. To determine if variability in glucocorticoid receptor (GR) expression might affect ex vivo generation of EBs, expression of αa and γ GR isoforms (αaGR and γGR) by EBs from 10 AB and 5 CB was investigated. While EBs from all donors expressed αaGR, γGR was not expressed by EBs obtained from CB and from AB that generated high numbers of EBs ex vivo, suggesting that activation of γGR in EBs is ontogenetically activated in a subset of AB and may predicts poor expansion. Ex vivo produced EBs are megaloblastic (30 to 50 μm). EPO decreased their size from 40.1±1.4 to 11.6±0.3 μm by 96 h (p<0.01). Although still macrocytic (adult normocytic red cells are 8 μm), these cells are smaller than fetal red cells (12.5 μm) and therefore suitable for clinical use. Inclusion of bovine components in HEMAser precludes its use for clinical purposes. Therefore, optimal growth factor and hormone combinations identified in HEMAser were used to formulate a medium composed of pharmaceutical grade human albumin, human albumin-based-lipid liposomes and iron-saturated recombinant human-tranferrin (HEMAdef). HEMAdef sustained EB amplification as efficiently as HEMAser from CB MNC and 10-fold higher than HEMAser from AB MNC. Moreover, the numbers of EBs generated in HEMAdef by adult MNC were similar to those generated by CB MNC (750×106 vs 500×106 per 106 MNC from AB and CB, respectively). Assuming that MNC contain 102-103 EB progenitors (CD34pos cells represent 0.1% of MNC and erythroid progenitors represent 10% of CD34pos cells), it was calculated that the generation of 750×106 EBs from the progenitors present in 106 adult MNC required 19-23 divisions, a number below the theoretical Hayflick's limit for somatic cell divisions of 35. These results indicate that at least a subset of AB donors is suitable to produce ex-vivo erythroid cells for transfusion and that it should be possible, by optimizing HEMAdef components, to further increase the number of EBs that can be generated ex-vivo from AB. Disclosures: No relevant conflicts of interest to declare.

APA, Harvard, Vancouver, ISO, and other styles

47

Seeger, W., U. Schneider, B. Kreusler, E. von Witzleben, D. Walmrath, F. Grimminger, and J. Neppert. "Reproduction of transfusion-related acute lung injury in an ex vivo lung model [see comments]." Blood 76, no. 7 (October 1, 1990): 1438–44. http://dx.doi.org/10.1182/blood.v76.7.1438.1438.

Full text

Abstract:

Abstract Leukoagglutinins are implicated in transfusion-related acute lung injury (TRALI). In the present study, severe lung vascular leakage was reproduced by application of a leukoagglutinating antibody of anti-5b specificity in an ex vivo lung model. The antibody originated from a multiparous donor-plasma, observed to cause noncardiogenic edema during transfusion therapy. Heated full plasma (anti-5b-titer 1/128) or purified immunoglobulin G fraction was used for the studies. Ex vivo isolated rabbit lungs were perfused with albumin buffer, and human granulocytes (PMN) were admixed to the recirculating perfusate. In presence of anti-5b antibody plus 5b-positive PMN plus rabbit plasma as complement-source, severe lung edema occurred after a latent period of 3 to 6 hours. Pulmonary artery pressure was only transiently and moderately increased, and the leakage reaction could be traced back to a several-fold increase in lung vascular permeability. In contrast, no vascular leakage was noted in lungs perfused in the absence of anti-5b antibody, PMN, or rabbit plasma. Moreover, no permeability increase occurred on use of 5b-negative PMN. This reproduction of TRALI in an ex vivo lung model corroborates the role of leukoagglutinating antibodies in initiating PMN-dependent respiratory distress and suggests a contribution of concomitant complement activation.

APA, Harvard, Vancouver, ISO, and other styles

48

Seeger, W., U. Schneider, B. Kreusler, E. von Witzleben, D. Walmrath, F. Grimminger, and J. Neppert. "Reproduction of transfusion-related acute lung injury in an ex vivo lung model [see comments]." Blood 76, no. 7 (October 1, 1990): 1438–44. http://dx.doi.org/10.1182/blood.v76.7.1438.bloodjournal7671438.

Full text

Abstract:

Leukoagglutinins are implicated in transfusion-related acute lung injury (TRALI). In the present study, severe lung vascular leakage was reproduced by application of a leukoagglutinating antibody of anti-5b specificity in an ex vivo lung model. The antibody originated from a multiparous donor-plasma, observed to cause noncardiogenic edema during transfusion therapy. Heated full plasma (anti-5b-titer 1/128) or purified immunoglobulin G fraction was used for the studies. Ex vivo isolated rabbit lungs were perfused with albumin buffer, and human granulocytes (PMN) were admixed to the recirculating perfusate. In presence of anti-5b antibody plus 5b-positive PMN plus rabbit plasma as complement-source, severe lung edema occurred after a latent period of 3 to 6 hours. Pulmonary artery pressure was only transiently and moderately increased, and the leakage reaction could be traced back to a several-fold increase in lung vascular permeability. In contrast, no vascular leakage was noted in lungs perfused in the absence of anti-5b antibody, PMN, or rabbit plasma. Moreover, no permeability increase occurred on use of 5b-negative PMN. This reproduction of TRALI in an ex vivo lung model corroborates the role of leukoagglutinating antibodies in initiating PMN-dependent respiratory distress and suggests a contribution of concomitant complement activation.

APA, Harvard, Vancouver, ISO, and other styles

49

Franke, Maximilian, Michael Bieber, Guido Stoll, and Michael Klaus Schuhmann. "Validity and Efficacy of Methods to Define Blood Brain Barrier Integrity in Experimental Ischemic Strokes: A Comparison of Albumin Western Blot, IgG Western Blot and Albumin Immunofluorescence." Methods and Protocols 4, no. 1 (March 23, 2021): 23. http://dx.doi.org/10.3390/mps4010023.

Full text

Abstract:

The clinical and preclinical research of ischemic strokes (IS) is becoming increasingly comprehensive, especially with the emerging evidence of complex thrombotic and inflammatory interactions. Within these, the blood brain barrier (BBB) plays an important role in regulating the cellular interactions at the vascular interface and is therefore the object of many IS-related questions. Consequently, valid, economic and responsible methods to define BBB integrity are necessary. Therefore, we compared the three ex-vivo setups albumin Western blot (WB), IgG WB and albumin intensity measurement (AIM) with regard to validity as well as temporal and economic efficacy. While the informative value of the three methods correlated significantly, the efficacy of the IgG WB dominated.

APA, Harvard, Vancouver, ISO, and other styles

50

Chowdhury, Golam MI, Lihong Jiang, Douglas L. Rothman, and Kevin L. Behar. "The Contribution of Ketone Bodies to Basal and Activity-Dependent Neuronal Oxidation in Vivo." Journal of Cerebral Blood Flow & Metabolism 34, no. 7 (April 30, 2014): 1233–42. http://dx.doi.org/10.1038/jcbfm.2014.77.

Full text

Abstract:

The capacity of ketone bodies to replace glucose in support of neuronal function is unresolved. Here, we determined the contributions of glucose and ketone bodies to neocortical oxidative metabolism over a large range of brain activity in rats fasted 36 hours and infused intravenously with [2,4- 13 C2]-D-β-hydroxybutyrate (BHB). Three animal groups and conditions were studied: awake ex vivo, pentobarbital-induced isoelectricity ex vivo, and halothane-anesthetized in vivo, the latter data reanalyzed from a recent study. Rates of neuronal acetyl-CoA oxidation from ketone bodies ( VaccoA-kbN) and pyruvate ( VpdhN), and the glutamate-glutamine cycle ( Vcyc) were determined by metabolic modeling of 13C label trapped in major brain amino acid pools. VacCoA-kbN increased gradually with increasing activity, as compared with the steeper change in tricarboxylic acid (TCA) cycle rate ( VtcaN), supporting a decreasing percentage of neuronal ketone oxidation: ˜100% (isoelectricity), 56% (halothane anesthesia), 36% (awake) with the BHB plasma levels achieved in our experiments (6 to 13 mM). In awake animals ketone oxidation reached saturation for blood levels > 17 mM, accounting for 62% of neuronal substrate oxidation, the remainder (38%) provided by glucose. We conclude that ketone bodies present at sufficient concentration to saturate metabolism provides full support of basal (housekeeping) energy needs and up to approximately half of the activity-dependent oxidative needs of neurons.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Ex vivo oxidation of albumin'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles