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1.
J Am Soc Mass Spectrom ; 35(8): 1826-1837, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39057601

RESUMEN

Labeling with deuterium oxide (D2O) has emerged as one of the preferred approaches for measuring the synthesis of individual proteins in vivo. In these experiments, the synthesis rates of proteins are determined by modeling mass shifts in peptides during the labeling period. This modeling depends on a theoretical maximum enrichment determined by the number of labeling sites (NEH) of each amino acid in the peptide sequence. Currently, NEH is determined from one set of published values. However, it has been demonstrated that NEH can differ between species and potentially tissues. The goal of this work was to determine the number of NEH for each amino acid within a given experiment to capture the conditions unique to that experiment. We used four methods to compute the NEH values. To test these approaches, we used two publicly available data sets. In a de novo approach, we compute NEH values and the label enrichment from the abundances of three mass isotopomers. The other three methods use the complete isotope profiles and body water enrichment in deuterium as an input parameter. They determine the NEH values by (1) minimizing the residual sum of squares, (2) from the mole percent excess of labeling, and (3) the time course profile of the depletion of the relative isotope abundance of monoisotope. In the test samples, the method using residual sum of squares performed the best. The methods are implemented in a tool for determining the NEH for each amino acid within a given experiment to use in the determination of protein synthesis rates using D2O.


Asunto(s)
Cromatografía Líquida con Espectrometría de Masas , Animales , Aminoácidos/química , Aminoácidos/análisis , Aminoácidos/metabolismo , Óxido de Deuterio , Cromatografía Líquida con Espectrometría de Masas/métodos , Péptidos/química , Péptidos/análisis , Proteínas/química , Proteínas/análisis , Proteínas/metabolismo
2.
Int J Mol Sci ; 25(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39062977

RESUMEN

The ability of thermoresponsive polymers to respond to temperature with a reversible conformational change makes them promising 'smart' materials for solutions in medical and biotechnological applications. In this work, two such polymers and structural isomers were studied: poly(N-isopropyl acrylamide) (PNiPAm) and poly(2-isopropyl-2-oxazoline) (PiPOx). We compare the critical solution temperatures (CST) of these polymers in D2O and H2O in the presence of Hofmeister series salts, as results obtained under these different solvent conditions are often compared. D2O has a higher dipole moment and electronegativity than H2O, which could significantly alter the CST transition. We used two complementary methods to measure the CST, dynamic light scattering (DLS) and differential scanning calorimetry (DSC) and found that the CST decreased significantly in D2O compared to H2O. In the presence of highly concentrated kosmotropes, the CST of both polymers decreased in both solvents. The influence of the kosmotropic anions was smaller than the water isotope effect at low ionic strengths but considerably higher at physiological ionic strengths. However, the Hofmeister anion effect was quantitatively different in H2O than in D2O, with the largest relative differences observed for Cl-, where the CSTs in D2O decreased more than in H2O measured by DLS but less by DSC. PiPOx was more sensitive than PNiPAm to the presence of chaotropes. It exhibited much higher transition enthalpies and multistep transitions, especially in aqueous solutions. Our results highlight that measurements of thermoresponsive polymer properties in D2O cannot be compared directly or quantitatively to application conditions or even measurements performed in H2O.


Asunto(s)
Polímeros , Solventes , Temperatura , Solventes/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Resinas Acrílicas/química , Óxido de Deuterio/química , Agua/química , Soluciones
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124723, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38941753

RESUMEN

The impact of microbial infections is increasing over time, and it is one of the major reasons for death in both developed and developing countries. colistin is considered as the antibiotic of last choice for infections brought by major multidrug-resistant (MDR), gram-negative bacteria such as Enterobacter species, Acinetobacter species, and Pseudomonas aeruginosa. Existing approaches to diagnose these resistant species are relatively slow and take up to 2 to 3 days. In this work, we propose a novel interdisciplinary method based on Raman spectroscopy and heavy water to identify colistin-resistant microbes. Our hypothesis is based on the fact that resistant bacteria will be metabolically active in the culture medium containing antibiotics and heavy water, and these bacteria will take up deuterium instead of hydrogen to newly synthesized lipids and proteins. This effect will generate a 'C - D' bond-specific Raman spectral marker. Successful identification of this band in the spectral profile can confirm the presence of colistin-resistant bacteria. We have validated the efficacy of this approach in identifying colistin-resistant bacteria spiked in artificial urine and have compared sensitivity at different bacterial concentrations. Overall findings suggest that heavy water can potentially serve as a suitable Raman probe for identifying metabolically active colistin-resistant bacteria via urine under clinically implementable time and can be used in clinical settings after validation.


Asunto(s)
Colistina , Óxido de Deuterio , Espectrometría Raman , Espectrometría Raman/métodos , Óxido de Deuterio/química , Colistina/farmacología , Colistina/química , Antibacterianos/farmacología , Antibacterianos/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
4.
J Exp Biol ; 227(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38916067

RESUMEN

Black soldier fly (Hermetia illucens) larvae are used to upcycle biowaste into insect biomass for animal feed. Previous research on black soldier fly has explored the assimilation of dietary fatty acids (FAs), but endogenous FA synthesis and modification remain comparatively unexplored. This study presents a 1H/2H-NMR methodology for measuring lipid synthesis in black soldier fly larvae using diluted deuterated water (2H2O) as a stable isotopic tracer delivered through the feeding media. This approach was validated by measuring 2H incorporation into the larvae's body water and consequent labelling of FA esterified into triacylglycerols. A 5% 2H enrichment in the body water, adequate to label the FA, is achieved after 24 h in a substrate with 10% 2H2O. A standard feeding trial using an invasive macroalgae was designed to test this method, revealing de novo lipogenesis was lower in larvae fed with macroalgae, probably related to the poor nutritional value of the diet.


Asunto(s)
Óxido de Deuterio , Larva , Espectroscopía de Resonancia Magnética , Algas Marinas , Animales , Larva/metabolismo , Larva/crecimiento & desarrollo , Algas Marinas/metabolismo , Algas Marinas/química , Óxido de Deuterio/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Alimentación Animal/análisis , Ácidos Grasos/metabolismo , Ácidos Grasos/análisis , Lípidos/análisis , Dípteros/metabolismo , Simuliidae/metabolismo , Simuliidae/crecimiento & desarrollo , Dieta/veterinaria
5.
Plant Cell Physiol ; 65(6): 986-998, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38590126

RESUMEN

Isotope labeling coupled with mass spectrometry imaging (MSI) presents a potent strategy for elucidating the dynamics of metabolism at cellular resolution, yet its application to plant systems is scarce. It has the potential to reveal the spatio-temporal dynamics of lipid biosynthesis during plant development. In this study, we explore its application to galactolipid biosynthesis of an aquatic plant, Lemna minor, with D2O labeling. Specifically, matrix-assisted laser desorption/ionization-MSI data of two major galactolipids in L. minor, monogalactosyldiacylglycerol and digalactosyldiacylglycerol, were studied after growing in 50% D2O media over a 15-day time period. When they were partially labeled after 5 d, three distinct binomial isotopologue distributions were observed corresponding to the labeling of partial structural moieties: galactose only, galactose and a fatty acyl chain and the entire molecule. The temporal change in the relative abundance of these distributions follows the expected linear pathway of galactolipid biosynthesis. Notably, their mass spectrometry images revealed the localization of each isotopologue group to the old parent frond, the intermediate tissues and the newly grown daughter fronds. Besides, two additional labeling experiments, (i) 13CO2 labeling and (ii) backward labeling of completely 50% D2O-labeled L. minor in H2O media, confirm the observations in forward labeling. Furthermore, these experiments unveiled hidden isotopologue distributions indicative of membrane lipid restructuring. This study suggests the potential of isotope labeling using MSI to provide spatio-temporal details in lipid biosynthesis in plant development.


Asunto(s)
Araceae , Galactolípidos , Marcaje Isotópico , Galactolípidos/metabolismo , Galactolípidos/biosíntesis , Marcaje Isotópico/métodos , Araceae/metabolismo , Araceae/crecimiento & desarrollo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Óxido de Deuterio/metabolismo
6.
Pflugers Arch ; 476(6): 993-1005, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38438679

RESUMEN

Increase in transendothelial water permeability is an essential etiological factor in a variety of diseases like edema and shock. Despite the high clinical relevance, there has been no precise method to detect transendothelial water flow until now. The deuterium oxide (D2O) dilution method, already established for measuring transepithelial water transport, was used to precisely determine the transendothelial water permeability. It detected appropriate transendothelial water flow induced by different hydrostatic forces. This was shown in four different endothelial cell types. The general experimental setup was verified by gravimetry and absorbance spectroscopy. Determination of transendothelial electrical resistance (TEER) and immunocytochemical staining for proteins of the cell-cell contacts were performed to ensure that no damage to the endothelium occurred because of the measurements. Furthermore, endothelial barrier function was modulated. Measurement of transendothelial water flux was verified by measuring the TEER, the apparent permeability coefficient and the electrical capacity. The barrier-promoting substances cyclic adenosine monophosphate and iloprost reduced TEER and electrical capacity and increased permeability. This was accompanied by a reduced transendothelial water flux. In contrast, the barrier-damaging substances thrombin, histamine and bradykinin reduced TEER and electrical capacity, but increased permeability. Here, an increased water flow was shown. This newly established in vitro method for direct measurement of transendothelial water permeability was verified as a highly precise technique in various assays. The use of patient-specific endothelial cells enables individualized precision medicine in the context of basic edema research, for example regarding the development of barrier-protective pharmaceuticals.


Asunto(s)
Óxido de Deuterio , Óxido de Deuterio/metabolismo , Humanos , Impedancia Eléctrica , Agua/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Permeabilidad , Animales , Endotelio Vascular/metabolismo , Endotelio Vascular/efectos de los fármacos , Permeabilidad Capilar/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos
7.
Transplant Proc ; 56(1): 223-227, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38199859

RESUMEN

The University of Wisconsin (UW) solution is the most effective preservation solution currently used; however, to safely use expanded-criteria donor grafts, a new cold storage solution that alleviates graft injury more effectively is required. We prepared a heavy water (D2O)-containing buffer, Dsol, and observed strong protective effects during extended cold storage of rat hearts and livers. In the current study, we modified Dsol (mDsol) and tested its efficacy. The aim of the present study was to determine whether mDsol could protect the rat liver more effectively than the UW solution and to clarify the roles of D2O and deferoxamine (DFX). Rat livers were subjected to cold storage for 48 hours in test solutions: UW, mDsol, mDsol without D2O or DFX (mDsol-D2O[-], mDsol-DFX[-]), and subsequently reperfused on an isolated perfused rat liver for 90 minutes at 37°C. In the UW group, the liver was dehydrated during cold storage and rapidly expanded during reperfusion. Accordingly, the cumulative weight change was the highest in the UW group, together with augmented portal veinous resistance and ALT leakage and decreased oxygen consumption rate and bile production. These changes were significantly suppressed in the mDsol-treated group. In the mDsol-D2O(-) and mDsol-DFX(-) groups offered partial protection. In conclusion, mDsol appeared to be superior to the UW solution for simple cold storage of the rat liver, presumably due to improved microcirculation in the early phase of reperfusion. Both heavy water and deferoxamine are essential for alleviating seamless organ swelling that occurs during cold storage and subsequent reperfusion.


Asunto(s)
Trasplante de Hígado , Soluciones Preservantes de Órganos , Humanos , Ratas , Animales , Óxido de Deuterio/farmacología , Deferoxamina/farmacología , Hígado , Soluciones Preservantes de Órganos/farmacología , Reperfusión , Glutatión/farmacología , Alopurinol/farmacología , Insulina/farmacología , Rafinosa/farmacología , Preservación de Órganos , Adenosina
8.
Curr Protoc ; 4(1): e970, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38270527

RESUMEN

Raman microscopy is a vibrational imaging technology that can detect molecular chemical bond vibrational signals. Since this signal is originated from almost every vibrational mode of molecules with different vibrational energy levels, it provides spatiotemporal distribution of various molecules in living organisms without the need for any labeling. The limitations of low signal strength in Raman microscopy have been effectively addressed by incorporating a stimulated emission process, leading to the development of stimulated Raman scattering (SRS) microscopy. Furthermore, the issue of low spatial resolution has been resolved through the application of computational techniques, specifically image deconvolution. In this article, we present a comprehensive guide to super-resolution SRS microscopy using an Adam-based pointillism deconvolution (A-PoD) algorithm, complemented by a user-friendly graphical user interface (GUI). We delve into the crucial parameters and conditions necessary for achieving super-resolved images through SRS imaging. Additionally, we provide a step-by-step walkthrough of the preprocessing steps and the use of GUI-supported A-PoD. This complete package offers a user-friendly platform for super-resolution SRS microscopy, enhancing the versatility and applicability of this advanced microscopy technique to reveal nanoscopic multimolecular nature. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Super-resolution stimulated Raman scattering microscopy with graphical user interface-supported A-PoD Support Protocol: Deuterium labeling on cells with heavy water for metabolic imaging.


Asunto(s)
Microscopía , Microscopía Óptica no Lineal , Algoritmos , Óxido de Deuterio , Etiquetado de Productos
9.
Health Phys ; 126(3): 125-133, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38011073

RESUMEN

ABSTRACT: Field experiments were performed to evaluate the deposition velocity of tritium oxide within a forest environment at the Savannah River Site near Aiken, SC. Field releases were designed to guide selection of deposition velocity values for use in safety-basis modeling. Six releases of deuterium oxide were conducted in 2020 and 2021 with corresponding air samples during and following each release. Samples were analyzed to determine the deuterium-to-hydrogen ratio in water and converted to concentrations of deuterium in the air during the experiment. Measurements were compared to prior model simulations to evaluate model performance and deposition velocity estimates. Field releases demonstrated vertical and horizontal mixing of a plume in a forest. Predicted deposition velocities ranged from 2.4 to 5.4 cm s -1 on average. In all cases, model simulations underpredicted deuterium concentration by 1 to 2 orders of magnitude, indicating the model does not sufficiently mix the plume into the forest. While the model underestimated the transfer of material downward through the forest, it does suggest that the model's estimates are conservative for making downwind dose estimates because of lower plume depletion, leading to higher concentration and dose estimates. While the field releases do not cover all possible meteorological conditions, we conclude it is appropriate to use a non-zero deposition velocity when performing safety-basis modeling of tritium oxide based on conservatism within the model. A recommendation of 1.0 cm s -1 as a deposition velocity is made, which is beyond the 95 th percentile value estimated from the prior modeling study.


Asunto(s)
Bosques , Agua , Óxido de Deuterio , Deuterio , Tritio/análisis
10.
Magn Reson Med ; 91(2): 681-686, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37849055

RESUMEN

PURPOSE: Tail-vein catheterization and subsequent in-magnet infusion is a common route of administration of deuterium (2 H)-labeled substrates in small-animal deuterium (D) MR studies. With mice, because of the tail vein's small diameter, this procedure is challenging. It requires considerable personnel training and practice, is prone to failure, and may preclude serial studies. Motivated by the need for an alternative, the time courses for common small-molecule deuterated substrates and downstream metabolites in brain following subcutaneous infusion were determined in mice and are presented herein. METHODS: Three 2 H-labeled substrates-[6,6-2 H2 ]glucose, [2 H3 ]acetate, and [3,4,4,4-2 H4 ]beta-hydroxybutyrate-and 2 H2 O were administered to mice in-magnet via subcutaneous catheter. Brain time courses of the substrates and downstream metabolites (and semi-heavy water) were determined via single-voxel DMRS. RESULTS: Subcutaneous catheter placement and substrate administration was readily accomplished with limited personnel training. Substrates reached pseudo-steady state in brain within ∼30-40 min of bolus infusion. Time constants characterizing the appearance in brain of deuterated substrates or semi-heavy water following 2 H2 O administration were similar (∼15 min). CONCLUSION: Administration of deuterated substrates via subcutaneous catheter for in vivo DMRS experiments with mice is robust, requires limited personnel training, and enables substantial dosing. It is suitable for metabolic studies where pseudo-steady state substrate administration/accumulation is sufficient. It is particularly advantageous for serial longitudinal studies over an extended period because it avoids inevitable damage to the tail vein following multiple catheterizations.


Asunto(s)
Encéfalo , Cola (estructura animal) , Ratones , Animales , Óxido de Deuterio , Deuterio , Cola (estructura animal)/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo
11.
J Biomed Opt ; 28(11): 116001, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38078156

RESUMEN

Significance: Changes in lipid, water, and collagen (LWC) content in tissue are associated with numerous medical abnormalities (cancer, atherosclerosis, and Alzheimer's disease). Standard imaging modalities are limited in resolution, specificity, and/or penetration for quantifying these changes. Short-wave infrared (SWIR) photoacoustic imaging (PAI) has the potential to overcome these challenges by exploiting the unique optical absorption properties of LWC>1000 nm. Aim: This study's aim is to harness SWIR PAI for mapping LWC changes in tissue. The focus lies in devising a reflection-mode PAI technique that surmounts current limitations related to SWIR light delivery. Approach: To enhance light delivery for reflection-mode SWIR PAI, we designed a deuterium oxide (D2O, "heavy water") gelatin (HWG) interface for opto-acoustic coupling, intended to significantly improve light transmission above 1200 nm. Results: HWG permits light delivery >1 mJ up to 1850 nm, which was not possible with water-based coupling (>1 mJ light delivery up to 1350 nm). PAI using the HWG interface and the Visualsonics Vevo LAZR-X reveals a signal increase up to 24 dB at 1720 nm in lipid-rich regions. Conclusions: By overcoming barriers related to light penetration, the HWG coupling interface enables accurate quantification/monitoring of biomarkers like LWC using reflection-mode PAI. This technological stride offers potential for tracking changes in chronic diseases (in vivo) and evaluating their responses to therapeutic interventions.


Asunto(s)
Técnicas Fotoacústicas , Óxido de Deuterio , Técnicas Fotoacústicas/métodos , Diagnóstico por Imagen , Agua , Lípidos
12.
Int J Mol Sci ; 24(20)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37895078

RESUMEN

Mass spectrometry has been an essential technique for the investigation of the metabolic pathways of living organisms since its appearance at the beginning of the 20th century. Due to its capability to resolve isotopically labeled species, it can be applied together with stable isotope tracers to reveal the transformation of particular biologically relevant molecules. However, low-resolution techniques, which were used for decades, had limited capabilities for untargeted metabolomics, especially when a large number of compounds are labelled simultaneously. Such untargeted studies may provide new information about metabolism and can be performed with high-resolution mass spectrometry. Here, we demonstrate the capabilities of high-resolution mass spectrometry to obtain insights on the metabolism of a model plant, Lepidium sativum, germinated in D2O and H218O-enriched media. In particular, we demonstrated that in vivo labeling with heavy water helps to identify if a compound is being synthesized at a particular stage of germination or if it originates from seed content, and tandem mass spectrometry allows us to highlight the substructures with incorporated isotope labels. Additionally, we found in vivo labeling useful to distinguish between isomeric compounds with identical fragmentation patterns due to the differences in their formation rates that can be compared by the extent of heavy atom incorporation.


Asunto(s)
Metabolómica , Espectrometría de Masas en Tándem , Óxido de Deuterio , Marcaje Isotópico/métodos , Metabolómica/métodos , Espectrometría de Masas en Tándem/métodos , Plantas/metabolismo , Isótopos/metabolismo
13.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37834251

RESUMEN

In the heavy petroleum industry, the development of efficient demulsifiers for the effective breaking of interfacially active asphaltenes (IAA)-stabilized water-in-heavy oil (W/HO) emulsions is a highly attractive but challenging goal. Herein, a novel nitrogen and oxygen containing demulsifier (JXGZ) with strong hydrogen bonding has been successfully synthesized through combining esterification, polymerization and amidation. Bottle tests indicated that JXGZ is effectual in quickly demulsifying the IAA-stabilized W/HO emulsions; complete dehydration (100%) to the emulsions could be achieved in 4 min at 55 °C using 400 ppm of JXGZ. In addition, the effects of demulsifier concentration, temperature and time on the demulsification performance of JXGZ are systematically analyzed. Demulsification mechanisms reveal that the excellent demulsification performance of JXGZ is attributed to the strong hydrogen bonding between JXGZ and water molecules (dual swords synergistic effect under hydrogen bond reconstruction). The interaction of the "dual swords synergistic effect" generated by two types of hydrogen bonds can quickly break the non-covalent interaction force (π-π stacking, Van der Waals force, hydrogen bonds) of IAA at the heavy oil-water interface, quickly promote the aggregation and coalescence of water molecules and finally achieve the demulsification of W/HO emulsions. These findings indicate that the JXGZ demulsifier shows engineering application prospects in the demulsification of heavy oil-water emulsions, and this work provides the key information for developing more efficient chemical demulsifiers suitable for large-scale industrial applications.


Asunto(s)
Petróleo , Agua , Emulsiones/química , Enlace de Hidrógeno , Agua/química , Óxido de Deuterio
14.
Toxicol In Vitro ; 93: 105703, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37751786

RESUMEN

OBJECTIVE: Deuterium oxide (D2O) or heavy water is known to have diverse biological activities and have a few therapeutic applications due to its limited toxicity to human subjects. In the present study, we investigated the mechanism of D2O-induced cytotoxicity in non-small cell lung cancer A549 cells. RESULTS: We found that D2O-treatment resulted in cytotoxicity, cell cycle arrest, and apoptosis in A549 cells in a dose-dependent fashion. In contrast, limited cytotoxicity was observed in lung fibroblasts WI38 cells. Moreover, D2O-treatment resulted in the disruption of the cellular microtubule network, accompanied by the generation of ROS. On further investigation, we observed that the intracellular ROS triggered autophagic responses in D2O-treated cells, leading to apoptosis by inhibiting the oncogenic PI3K/ Akt/ mTOR signaling. D2O-treatment was also found to enhance the efficacy of paclitaxel in A549 cells. SIGNIFICANCE: D2O induces autophagy-dependent apoptosis in A549 cells via ROS generation upon microtubule depolymerization and inhibition of PI3K/ Akt/ mTOR signaling. It augments the efficacy of other microtubule-targeting anticancer drug taxol, which indicates the potential therapeutic importance of D2O as an anticancer agent either alone or in combination with other chemotherapeutic drugs.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Células A549 , Óxido de Deuterio/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Apoptosis , Autofagia , Microtúbulos , Fosfatidilinositol 3-Quinasas/metabolismo
15.
Nano Lett ; 23(19): 8907-8913, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37772726

RESUMEN

Proteins are versatile, self-assembling nanoelectronic components, but their hopping conductivity is expected to be influenced by solvent fluctuations. The role of the solvent was investigated by measuring the single molecule conductance of several proteins in both H2O and D2O. The conductance of a homologous series of protein wires decreases more rapidly with length in D2O, indicating a 6-fold decrease in carrier diffusion constant relative to the same protein in H2O. The effect was found to depend on the specific aromatic amino acid composition. A tryptophan zipper protein showed a decrease in conductance similar to that of the protein wires, whereas a phenylalanine zipper protein was insensitive to solvent changes. Tryptophan contains an indole amine, whereas the phenylalanine aromatic ring has no exchangeable protons, so the effect of heavy water on conductance is a consequence of specific D- or H-interactions with the aromatic residues.


Asunto(s)
Proteínas , Triptófano , Óxido de Deuterio , Deuterio/química , Triptófano/química , Proteínas/química , Fenilalanina/química , Protones , Solventes
16.
J Phys Chem B ; 127(38): 8086-8094, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37722111

RESUMEN

D2O is commonly used as a solvent instead of H2O in spectroscopic studies of proteins, in particular, in infrared and nuclear-magnetic-resonance spectroscopy. D2O is chemically equivalent to H2O, and the differences, particularly in hydrogen-bond strength, are often ignored. However, replacing solvent water with D2O can affect not only the kinetics but also the structure and stability of biomolecules. Recent experiments have shown that even the mesoscopic structures and the elastic properties of biomolecular assemblies, such as amyloids and protein networks, can be very different in D2O and H2O. We discuss these findings, which probably are just the tip of the iceberg, and which seem to call for obtaining a better understanding of the H2O/D2O-isotope effect on water-water and water-protein interactions. Such improved understanding may change the differences between H2O and D2O as biomolecular solvents from an elephant in the room to an opportunity for protein research.


Asunto(s)
Proteínas , Agua , Agua/química , Proteínas/química , Solventes/química , Isótopos , Óxido de Deuterio/química
17.
ACS Sens ; 8(10): 3973-3984, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37725347

RESUMEN

Distinguishing between heavy water and regular water has been a continuing challenge since these isotopologues of water have very similar physical and chemical properties. We report the development and evaluation of a simple, inexpensive sensor capable of detecting liquid D2O and other isotopologues of liquid water through the measurement of electrical signals generated from a nanoporous alumina film. This electrical output, consisting of a sharp voltage pulse followed by a separate broad voltage pulse, is present during the application of microliter volumes of liquid. The amplitude and temporal characteristics of these pulses have been combined to enable four diagnostic parameters for sensing D2O and H218O. The sensing mechanism is based on different modification effects on the alumina surface by H2O and D2O, spatially localized variations in the surface potential of alumina induced by isotopically substituted water molecules, combined with the effect of isotopic composition on charge transfer. As a proof-of-concept demonstration, a sensing system has been developed that provides real-time detection of liquid D2O in a stand-alone system.


Asunto(s)
Óxido de Aluminio , Agua , Agua/química , Óxido de Deuterio
18.
Sci Data ; 10(1): 635, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37726365

RESUMEN

Metabolic stable isotope labeling with heavy water followed by liquid chromatography coupled with mass spectrometry (LC-MS) is a powerful tool for in vivo protein turnover studies. Several algorithms and tools have been developed to determine the turnover rates of peptides and proteins from time-course stable isotope labeling experiments. The availability of benchmark mass spectrometry data is crucial to compare and validate the effectiveness of newly developed techniques and algorithms. In this work, we report a heavy water-labeled LC-MS dataset from the murine liver for protein turnover rate analysis. The dataset contains eighteen mass spectral data with their corresponding database search results from nine different labeling durations and quantification outputs from d2ome+ software. The dataset also contains eight mass spectral data from two-dimensional fractionation experiments on unlabeled samples.


Asunto(s)
Hígado , Proteoma , Animales , Ratones , Cromatografía Liquida , Óxido de Deuterio , Espectrometría de Masas en Tándem
19.
Chem Senses ; 482023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37589415

RESUMEN

Deuterium oxide (D2O) is water in which the heavier and rare isotope deuterium replaces both hydrogens. We have previously shown that D2O has a distinctly sweet taste, mediated by the T1R2/T1R3 sweet taste receptor. Here, we explore the effect of heavy water on T1R2 and T1R3 subunits. We show that D2O activates T1R3-transfected HEK293T cells similarly to T1R2/T1R3-transfected cells. The response to glucose dissolved in D2O is higher than in water. Mutations of phenylalanine at position 7305.40 in the transmembrane domain of T1R3 to alanine, leucine, or tyrosine impair or diminish activation by D2O, suggesting a critical role for T1R3 TMD domain in relaying the heavy water signal.


Asunto(s)
Papilas Gustativas , Gusto , Humanos , Óxido de Deuterio , Células HEK293 , Glucosa/farmacología
20.
PeerJ ; 11: e15564, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397014

RESUMEN

Background: Premature ovarian failure (POF) is defined as the cessation of ovarian function before the age of 40 years, imposing a significant health burden on patients. However, effective etiological therapy for POF is scarce. Thus, we aimed to explore the protective role and targets of hydrogen-rich water (HRW) in POF. Methods: Based on cyclophosphamide (CTX)-induced POF rat models, the protective role of HRW treatment was mainly determined through serum 17-ß-estradiol (E2), follicle-stimulating hormone (FSH), anti-mullerian hormone (AMH) levels, ovarian histomorphological analysis, and TUNEL assay. Tandem mass tag (TMT)-based quantitative proteomic analysis was then conducted on ovarian tissues, and the targets of HRW in POF were identified integrating differential expression analysis, functional enrichment analysis, and interaction analysis. Results: In HRW treatment of POF rats, the serum AMH and E2 levels significantly increased, and FSH level significantly reduced, indicating the protective role of HRW. After TMT quantitative proteomic analysis, a total of 16 candidate differentially expressed proteins (DEPs) were identified after the cross analysis of DEPs from POF vs. control and POF+HRW vs. POF groups, which were found to be significantly enriched in 296 GO terms and 36 KEGG pathways. The crucial targets, RT1-Db1 and RT1-Bb, were finally identified based on both protein-protein interaction network and GeneMANIA network. Conclusions: The HRW treatment could significantly alleviate the ovarian injury of POF rats; RT1-Db1 and RT1-Bb are identified as two crucial targets of HRW treatment in POF rats.


Asunto(s)
Óxido de Deuterio , Menopausia Prematura , Insuficiencia Ovárica Primaria , Animales , Femenino , Humanos , Ratas , Hormona Antimülleriana , Hormona Folículo Estimulante , Hidrógeno/farmacología , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/terapia , Proteómica , Óxido de Deuterio/uso terapéutico
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