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6. Effects of land use and slope position on selected soil physicochemical properties in Tekorsh Sub-Watershed, East Gojjam Zone, Ethiopia

Author

Bayle Dilnesa, Feyissa Samuel, and Tamiru Solomon

Subjects
physico-chemical, micronutrients, soil parameters, cultivated land, grazing land, Agriculture, Agriculture (General), S1-972
Abstract

In the Tekorsh Sub-Watershed, East Gojjam Zone, Ethiopia, researchers investigated the impact of land use patterns and slope position on selected soil physico-chemical parameters. The study area was arbitrarily divided into three slope positions (higher, middle, and lower), two land uses types (grazing and cultivated land), and two soil depths (0–20 and 20–40 cm) with three replications, based on the in situ field survey. For laboratory analysis, a total of 36 composite samples were obtained. Sand, clay, and silt fraction were highly significantly (P ≤ 0.05) affected by the interaction effect of the three factors. Clay and clay loam were the textural classes of the soil in the study area. The interaction effects of the three factors were highly significant (P ≤ 0.001) affected bulk density (D b), total porosity (TP), organic carbon (OC), available phosphorus (AP), exchangeable (Mg2+, Ca2+, and acidity), cation exchange capacity (CEC), and micronutrients (Fe, Mn, Cu, and Zn). The soils were medium to high (1.22–1.44 g/cm3) in D b, very high (45.66–63.13%) in TP, medium to high (15.72–19.56% v/v) in available water holding capacity, low to medium (1.37–2.91%) in OC, very low (1.65–7.68 mg/kg) in AP, high (4.62–5.36 cmol(+)/kg) in exchangeable Mg2+, very high in CEC (43.60–51.06 cmol(+)/kg), Fe (25.20–52.91 mg/kg), Mn (37.29–105.55 mg/kg), Cu (4.04–7.87 kg/kg), and Zn (0.83 2.53 kg/kg). In general, it was discovered that the majority of the assessed soil properties were better in grazing land than in soils utilized for cultivated land uses, and that the lower slope position was preferable to the upper and middle ones.

Published
2023
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8. Introductory Lecture:In VitroTranslation Analysis of Integral Membrane Proteins

Author

K Melchers, Bayle D, David L. Weeks, K. Bamberg, S. Hallen, and G. Sachs

Subjects
ATPase, Cell Biology, Biology, Biochemistry, Transmembrane protein, Transmembrane domain, Protein structure, Symporter, biology.protein, P-type ATPase, Molecular Biology, Peptide sequence, Integral membrane protein
Abstract

A method of in vitro translation scanning was applied to a variety of polytopic integral membrane proteins, a transition metal P type ATPase from Helicobacter pylori, the SERCA 2 ATPase, the gastric H+,K+ ATPase, the CCK-A receptor and the human ileal bile acid transporter. This method used vectors containing the N terminal region of the gastric H+,K+ ATPase or the N terminal region of the CCK-A receptor, coupled via a linker region to the last 177 amino acids of the beta-subunit of the gastric H+,K+ ATPase. The latter contains 5 potential N-linked glycosylation sites. Translation of vectors containing the cDNA encoding one, two or more putative transmembrane domains in the absence or presence of microsomes allowed determination of signal anchor or stop transfer properties of the putative transmembrane domains by the molecular weight shift on SDS PAGE. The P type ATPase from Helicobacter pylori showed the presence of 8 transmembrane segments with this method. The SERCA 2 Ca2+ ATPase with this method had 9 transmembrane co-translational insertion domains and coupled with other evidence these data resulted in a 11 transmembrane segment model. Translation of segments of the gastric H+,K+ ATPase provided evidence for only 7 transmembrane segments but coupled with other data established a 10 membrane segment model. The G7 protein, the CCK-A receptor showed the presence of 6 of the 7 transmembrane segments postulated for this protein. Translation of segments of the human ileal bile acid transporter showed the presence of 8 membrane insertion domains. However, translation of the intact protein provided evidence for an odd number of transmembrane segments, resulting in a tentative model containing 7 or 9 transmembrane segments. Neither G7 type protein appeared to have an arrangement of sequential topogenic signals consistent with the final assembled protein. This method provides a useful addition to methods of determining membrane domains of integral membrane proteins but must in general be utilized with other methods to establish the number of transmembrane alpha-helices.

Published
1997
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9. Na(+)/H(+) exchanger NHE3 has 11 membrane spanning domains and a cleaved signal peptide: topology analysis using in vitro transcription/translation

Author

Žižak, Mirza, Cavet, M. E., Bayle, D., Tse, C. M., Hallen, S., Sachs, G., and Donowitz, M.

Subjects
Na(+)/H(+) exchanger NHE3, membrane spaning domains, signal peptide, topology analysis, in vitro transcription/translation
Abstract

The transmembrane topology of Na(^+)/H(^+) exchanger NHE3 has been studied using in vitro transcription/translation of two types of fusion vectors designed to test membrane insertion properties of cDNA sequences encoding putative NHE3 membrane spanning domains (msds). These vectors encode N-terminal 101 (HKM0) or 139 (HKM1) amino acids of the H,K-ATPase alpha-subunit, a linker region and a reporter sequence containing five N-linked glycosylation consensus sites in the C-terminal 177 amino acids of the H,K-ATPase beta-subunit. The glycosylation status of the reporter sequence was used as a marker for the analysis of signal anchor and stop transfer properties of each putative msd in both the HKM0 and the HKM1 vectors. The linker region of the vectors was replaced by sequences that contain putative msds of NHE3 individually or in pairs. In vitro transcription/translation was performed using [(^35)S]methionine in a reticulocyte lysate system +/- microsomes, and the translation products were identified by autoradiography following separation using SDS-PAGE. We propose a revised NHE3 topology model, which contains a cleaved signal peptide followed by 11 msds, including extracellular orientation of the N-terminus and intracellular orientation of the C-terminus. The presence of a cleavable signal peptide in NHE3 was demonstrated by its cleavage from NHE3 during translational processing of full-length and truncated NHE3 in the presence of microsomes. Of 11 putative msds, six (msds 1, 2, 4, 7, 10, and 11) acted as both signal anchor and stop transfer sequences, while five (msds 3, 5, 6, 8, and 9) had signal anchor activities when tested alone. Of the latter, 3, 5, 6, and 9 were shown to act as stop transfer sequences after C-terminal extension. The actual membrane orientation of each sequential transmembrane segment of NHE3 was deduced from the membrane location of the N- and C-termini of NHE3. The regions between putative msds 8 and 9 and between msds 10 and 11, which correspond to the fourth and fifth extracellular loops, did not act as msds when tested alone. However, the extension of the fifth extracellular loop with adjacent putative msds showed some membrane-associated properties suggesting that the fifth extracellular loop might be acting as a "P-loop"-like structure.

Published
2000

13. The Topology of the α, β Subunits of the Gastric H/K ATPase

Author

Marie Besancon, Jai Moo Shin, Steve Hersey, Frederic Mercier, Bayle D, Keith Munson, Krister Bamberg, and George Sachs

Subjects
chemistry.chemical_classification, Membrane, Enzyme, chemistry, biology, Stereochemistry, Protein subunit, ATPase, biology.protein, Secretion, Protein secondary structure, Ion transporter, Amino acid
Abstract

Knowledge of the secondary structure of the gastric H/K ATPase,a P type transport ATPase, allows deductions as to the ion transport pathway across the membrane spanning domain of the large, 1033 amino acid catalytic a subunit and as to the site of interaction between the smaller, glycosylated, s subunit and the or subunit. The structure of this region of the enzyme also allows us to understand the molecular basis for inhibition of acid secretion by acid pump inhibitors, such as the substituted benzimidazoles and the K+ competitive type of H/K ATPase inhibitor.

Published
1994
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28. Introductory Lecture: In VitroTranslation Analysis of Integral Membrane Proteins

Author

Bayle, D., Weeks, D., Hallen, S., Melchers, K., Bamberg, K., and Sachs, G.

Abstract

AbstractA method of in vitrotranslation scanning was applied to a variety of polytopic integral membrane proteins, a transition metal P type ATPase from Helicobacter pylori, the SERCA 2 ATPase, the gastric H,KATPase, the CCK-A receptor and the human ileal bile acid transporter. This method used vectors containing the N terminal region of the gastric H,KATPase or the N terminal region of the CCK-A receptor, coupled via a linker region to the last 177 amino acids of the β-subunit of the gastric H,KATPase. The latter contains 5 potential N-linked glycosylation sites. Translation of vectors containing the cDNA encoding one, two or more putative transmembrane domains in the absence or presence of microsomes allowed determination of signal anchor or stop transfer properties of the putative transmembrane domains by the molecular weight shift on SDS PAGE. The P type ATPase from Helicobacter pylorishowed the presence of 8 transmembrane segments with this method. The SERCA 2 Ca2ATPase with this method had 9 transmembrane co-translational insertion domains and coupled with other evidence these data resulted in a 11 transmembrane segment model. Translation of segments of the gastric H,KATPase provided evidence for only 7 transmembrane segments but coupled with other data established a 10 membrane segment model. The G7 protein, the CCK-A receptor showed the presence of 6 of the 7 transmembrane segments postulated for this protein. Translation of segments of the human ileal bile acid transporter showed the presence of 8 membrane insertion domains. However, translation of the intact protein provided evidence for an odd number of transmembrane segments, resulting in a tentative model containing 7 or 9 transmembrane segments. Neither G7 type protein appeared to have an arrangement of sequential topogenic signals consistent with the final assembled protein. This method provides a useful addition to methods of determining membrane domains of integral membrane proteins but must in general be utilized with other methods to establish the number of transmembrane α-helices.

Published
1997
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29. Identification of membrane insertion sequences of the rabbit gastric cholecystokinin-A receptor by in vitro translation.

Author

Bayle, D, Weeks, D, and Sachs, G

Abstract

To determine which amino acid sequences account for transmembrane folding of G7 receptors, the membrane domain of the rabbit cholecystokinin-A (CCK-A) G-protein-coupled receptor has been investigated by in vitro transcription/translation of two types of fusion vectors containing sequences that include putative transmembrane segments. First, the seven putative transmembrane domains of the CCK-A receptor were inserted individually into pGEM vectors beginning with the cDNA encoding the first 101 (HK-M0) or 139 (HK-M1) amino acids of the alpha subunit of the gastric H, K-ATPase. These were separated by the cDNA for the inserted transmembrane domains from the cDNA encoding the last 177 amino acids of the beta subunit of the H,K-ATPase containing five N-linked glycosylation consensus sequences (Bamberg, K., and Sachs, G. (1994) J. Biol. Chem. 269, 16909-16919). Transcription/translation of these fusion vectors in rabbit reticulocyte lysate +/- dog pancreatic microsomes followed by SDS-polyacrylamide gel electrophoresis defined the presence of signal anchor sequences in HK-M0 by glycosylation and stop transfer sequences in HK-M1 by inhibition of glycosylation. Six out of the seven putative transmembrane domains had membrane insertion signals, but no membrane insertion activity was found for the H3 segment in these vectors. To test the effect of specific upstream and downstream sequences on membrane insertion, vectors were also made starting with the cDNA encoding the N terminus of the CCK-A receptor separated from the last 177 amino acids of the H,K-ATPase beta subunit by cDNA encoding CCK-A receptor sequences of different lengths. In addition to transcription/translation, endoglycosidase H treatment was used to verify glycosylation when multiple bands were found in the presence of microsomes. The four positive charges in the loop between H1 and H2 were required for the correct orientation of the first transmembrane domain. The H3 segment acted as a stop transfer sequence only when the whole N terminus and H3 were followed by the positive charges in the cytoplasmic loop between H3 and H4. The activity of H6 as a signal anchor sequence depended on preceding positive charges. These translation data using two types of fusion vectors establish a seven-transmembrane folding model using only in vitro translation for the CCK-A receptor beginning with two signal anchor sequences and then alternating stop transfer and signal anchor insertions. Positive charges between H1 and H2, H3 and H4, and H5 and H6 function as cytoplasmic anchors in the membrane folding of this receptor.

Published
1997

30. Identification of the site of inhibition by omeprazole of a alpha-beta fusion protein of the H,K-ATPase using site-directed mutagenesis.

Author

Lambrecht, N, Corbett, Z, Bayle, D, Karlish, S J, and Sachs, G

Abstract

The alpha subunit of eukaryotic P-type ATPases has ten experimentally defined transmembrane or membrane inserted segments. The fifth and sixth of these are short, not predicted by hydropathy analysis, do not insert independently into microsomal membranes, and are readily removed after tryptic digestion and therefore may be membrane inserted sequences. Acid transport by the gastric H, K-ATPase is covalently inhibited by several substituted pyridyl methylsulfinyl benzimidazoles, such as omeprazole. These act as probes of accessible extracytoplasmic thiols because they are accumulated in the acid transporting gastric vesicles and then convert to thiol reactive, cationic tetracyclic sulfenamides. Inhibition is due mainly to disulfide formation with Cys813 or Cys822 in M5/6 and perhaps with a contribution from Cys892 in the loop between transmembrane segment (TM) 7 and TM8. Identification of the specific cysteine responsible for inhibition should be able to define the turn between M5 and M6. The gastric H,K-ATPase alpha-beta heterodimer was expressed as a fusion protein in HEK 293 cells. Transient transfection resulted in most of the protein being retained in the endoplasmic reticulum with only core glycosylation and minor activity of the ATPase evident. Stable transfection resulted in plasma membrane localization of the protein and complex glycosylation. The transfected but not the control cells displayed cation-stimulated, SCH 28080-inhibited ATPase activity and SCH 28080- and omeprazole-inhibited 86Rb uptake. The two cysteines in M5/6 and Cys892 in the TM7/8 loop were mutated to the amino acids found in the Na,K-ATPase in order to determine which of the three cysteine residues were important for benzimidazole inhibition. Mutation of one, two, or all three cysteines did not alter enzyme activity, 86Rb transport, or SCH 28080 inhibition. Only removal of Cys822 blocked omeprazole inhibition of 86Rb transport. These data suggest that Cys822 is present in a region of the enzyme most easily accessed by the cationic sulfenamide formed by omeprazole, presumably the turn between M5 and M6.

Published
1998

31. The membrane topology of the rat sarcoplasmic and endoplasmic reticulum calcium ATPases by in vitro translation scanning.

Author

Bayle, D, Weeks, D, and Sachs, G

Abstract

The membrane topology of the rat endoplasmic reticulum (ER) and sarcoplasmic reticulum (SR) Ca2+ ATPases were investigated using in vitro transcription/translation of fusion vectors containing DNA sequences encoding putative membrane-spanning domains. The sequences of these Ca2+ ATPases are identical except for the COOH-terminal end, which contains an additional predicted transmembrane segment in the ER ATPase. The M0 and M1 fusion vectors (Bamberg, K., and Sachs, G. (1994) J. Biol. Chem. 269, 16909-16919) encode the NH2-terminal 101 (M0 vector) or 139 (M1 vector) amino acids of the H,K-ATPase alpha subunit followed by a linker region for insertion of putative transmembrane sequences and, finally, the COOH-terminal 177 amino acids of the H,K-ATPase beta subunit containing five N-linked glycosylation consensus sequences. The linker region was replaced by the putative transmembrane domains of the Ca2+ ATPases, either individually or in pairs. Transcription and translation were performed using [35S]methionine in a reticulocyte lysate system in the absence or presence of canine pancreatic microsomes. The translated fusion protein was identified by autoradiography following separation using SDS-polyacrylamide gel electrophoresis. When testing single transmembrane segments, this method detects signal anchor activity with M0 or stop transfer activity with M1. The first four predicted SERCA transmembrane domains acted as both signal anchor and stop transfer sequences. A construct containing the fifth predicted transmembrane segment was able to act only as a stop transfer sequence. The sixth transmembrane segment did not insert cotranslationally into the membrane. The seventh was able to act as both a signal anchor and stop transfer sequence, and the eighth showed stop transfer ability in the M1 vector. The ninth transmembrane segment had both signal anchor and stop transfer capacity, whereas the tenth transmembrane segment showed only stop transfer sequence properties. The eleventh transmembrane sequence, unique to the ER Ca2+ ATPase, had both signal anchor and stop transfer properties. These translation data provide direct experimental evidence for 8 or 9 of the 10 or 11 predicted transmembrane sequences in the current topological models for the SR or ER Ca2+ ATPases, respectively.

Published
1995

34. Susceptibility to oxidation and physicochemical properties of LDL in insulin-dependent diabetics

Author

Feillet, C., Roche, B., Tauveron, I., Bayle, D., Rock, E., Borel, P., Rayssiguier, Y., Thieblot, P., Andre Mazur, Unité de recherche Maladies Métaboliques et Micronutriments (U3M), Institut National de la Recherche Agronomique (INRA), and ProdInra, Migration

Subjects
Lipoproteins, LDL, Male, [SDV] Life Sciences [q-bio], Diabetes Mellitus, Type 1, [SDV]Life Sciences [q-bio], Humans, Middle Aged, Oxidation-Reduction, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

35. Changes in gene expression in the lungs of Mg-deficient mice are related to an inflammatory process

Author

Nasulewicz, A., Zimowska, W., Bayle, D., Stanislaw Dzimira, Madej, J., Rayssiguier, Y., Opolski, A., and Mazur, A.

Subjects
Inflammation, Mice, Inbred C57BL, Mice, Oxidative Stress, Leukocytes, Animals, Down-Regulation, Gene Expression, Female, Magnesium, Lung, Oligonucleotide Array Sequence Analysis, Up-Regulation
Abstract

It has been well documented that experimental hypomagnesemia in rodents evokes, as an early consequence, an inflammatory response. This also leads to the activation of cells producing reactive species of oxygen and, as a result, to the oxidative damage of tissues. Several studies have shown that lungs might be a specific target of Mg deficiency. Here, we report that 3 weeks of Mg deficiency in mice resulted in inflammatory processes in the lungs, including interstitial and perivascular pneumonia, manifested by the infiltration of leukocytes, plasmocytes and histiocytes, as well as the phenomenon of disseminated intravascular coagulation (DIC). These phenomena were accompanied by changes in gene expression assessed by cDNA array. In this study we identified 26 genes significantly changed by Mg deficiency, mostly involved in the anti-oxidative response, regulation of cell cycle and growth, apoptosis as well as cell-cell and cell-matrix interactions. We conclude that these changes are related to the phenomena of inflammatory and oxidative processes and consecutive remodeling occurring in the tissues as a result of Mg deficiency. This may have implications for at least several lung pathologies, including allergies, asthma, SIDS (Sudden Infant Death Syndrome) or facilitate formation of lung metastases.

43. Effects of Acute Physical Fatigue on Gaze Behavior in Expert Badminton Players.

Author

Loiseau Taupin M, Ruffault A, Slawinski J, and Bayle D

Subjects
Humans, Fatigue, Fixation, Ocular, Racquet Sports psychology
Abstract

Perceptual cognitive skills in real game settings, under conditions of fatigue, such as the ability to gather relevant visual information, are key factors in achieving motor goals in sports. The objectives were to evaluate the effects of acute physical fatigue on gaze behavior during a badminton game (Study 1) and in an unfavorable force ratio situation (Study 2). Six international-level badminton players played two sets and unfavorable force ratio situations while wearing eye-tracking glasses before and after a fatiguing task. During the set, fatiguing physical exercise led to fewer fixations per exchange and more fixations on one area of interest. During unfavorable force ratio situations, fatiguing physical exercise led to shorter fixation durations per exchange, shorter fixation durations on two areas of interest, and longer fixation durations on one area of interest. The results showed that gaze behaviors were adapted in acute physical fatigue conditions to maintain performance.

Published
2023
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44. Neural oscillations track natural but not artificial fast speech: Novel insights from speech-brain coupling using MEG.

Author

Hincapié Casas AS, Lajnef T, Pascarella A, Guiraud-Vinatea H, Laaksonen H, Bayle D, Jerbi K, and Boulenger V

Subjects
Adolescent, Adult, Female, Humans, Language, Male, Middle Aged, Motor Cortex physiology, Young Adult, Auditory Perception physiology, Brain physiology, Magnetoencephalography methods, Speech physiology
Abstract

Neural oscillations contribute to speech parsing via cortical tracking of hierarchical linguistic structures, including syllable rate. While the properties of neural entrainment have been largely probed with speech stimuli at either normal or artificially accelerated rates, the important case of natural fast speech has been largely overlooked. Using magnetoencephalography, we found that listening to naturally-produced speech was associated with cortico-acoustic coupling, both at normal (∼6 syllables/s) and fast (∼9 syllables/s) rates, with a corresponding shift in peak entrainment frequency. Interestingly, time-compressed sentences did not yield such coupling, despite being generated at the same rate as the natural fast sentences. Additionally, neural activity in right motor cortex exhibited stronger tuning to natural fast rather than to artificially accelerated speech, and showed evidence for stronger phase-coupling with left temporo-parietal and motor areas. These findings are highly relevant for our understanding of the role played by auditory and motor cortex oscillations in the perception of naturally produced speech., (Copyright © 2021. Published by Elsevier Inc.)

Published
2021
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45. Effects of Acute Physical Fatigue on Gaze Behavior and Performance During a Badminton Game.

Author

Loiseau-Taupin M, Ruffault A, Slawinski J, Delabarre L, and Bayle D

Abstract

In badminton, the ability to quickly gather relevant visual information is one of the most important determinants of performance. However, gaze behavior has never been investigated in a real-game setting (with fatigue), nor related to performance. The aim of this study was to evaluate the effect of fatigue on gaze behavior during a badminton game setting, and to determine the relationship between fatigue, performance and gaze behavior. Nineteen novice badminton players equipped with eye-tracking glasses played two badminton sets: one before and one after a fatiguing task. The duration and number of fixations for each exchange were evaluated for nine areas of interest. Performance in terms of points won or lost and successful strokes was not impacted by fatigue, however fatigue induced more fixations per exchange on two areas of interest (shuttlecock and empty area after the opponent's stroke). Furthermore, two distinct gaze behaviors were found for successful and unsuccessful performance: points won were associated with fixations on the boundary lines and few fixation durations on empty area before the participant's stroke; successful strokes were related to long fixation durations, few fixation durations on empty area and a large number of fixations on the shuttlecock, racket, opponent's upper body and anticipation area. This is the first study to use a mobile eye-tracking system to capture gaze behavior during a real badminton game setting: fatigue induced changes in gaze behavior, and successful and unsuccessful performance were associated with two distinct gaze behaviors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Loiseau-Taupin, Ruffault, Slawinski, Delabarre and Bayle.)

Published
2021
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46. Magnesium Deficiency Alters Expression of Genes Critical for Muscle Magnesium Homeostasis and Physiology in Mice.

Author

Bayle D, Coudy-Gandilhon C, Gueugneau M, Castiglioni S, Zocchi M, Maj-Zurawska M, Palinska-Saadi A, Mazur A, Béchet D, and Maier JA

Subjects
Animals, Disease Models, Animal, Energy Metabolism genetics, Mice, Mice, Inbred C57BL, Muscle Fibers, Skeletal metabolism, Signal Transduction genetics, Cation Transport Proteins metabolism, Homeostasis genetics, Magnesium metabolism, Magnesium Deficiency genetics, Muscle, Skeletal metabolism
Abstract

Chronic Mg 2+ deficiency is the underlying cause of a broad range of health dysfunctions. As 25% of body Mg 2+ is located in the skeletal muscle, Mg 2+ transport and homeostasis systems (MgTHs) in the muscle are critical for whole-body Mg 2+ homeostasis. In the present study, we assessed whether Mg 2+ deficiency alters muscle fiber characteristics and major pathways regulating muscle physiology. C57BL/6J mice received either a control, mildly, or severely Mg 2+ -deficient diet (0.1%; 0.01%; and 0.003% Mg 2+ wt/wt, respectively) for 14 days. Mg 2+ deficiency slightly decreased body weight gain and muscle Mg 2+ concentrations but was not associated with detectable variations in gastrocnemius muscle weight, fiber morphometry, and capillarization. Nonetheless, muscles exhibited decreased expression of several MgTHs ( MagT1 , CNNM2 , CNNM4 , and TRPM6 ). Moreover, TaqMan low-density array (TLDA) analyses further revealed that, before the emergence of major muscle dysfunctions, even a mild Mg 2+ deficiency was sufficient to alter the expression of genes critical for muscle physiology, including energy metabolism, muscle regeneration, proteostasis, mitochondrial dynamics, and excitation-contraction coupling.

Published
2021
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47. Effects of the apple matrix on the postprandial bioavailability of flavan-3-ols and nutrigenomic response of apple polyphenols in minipigs challenged with a high fat meal.

Author

Monfoulet LE, Buffière C, Istas G, Dufour C, Le Bourvellec C, Mercier S, Bayle D, Boby C, Remond D, Borel P, Rodriguez-Mateos A, Milenkovic D, and Morand C

Subjects
Animals, Biological Availability, Diet, High-Fat, Male, Nutrigenomics, Postprandial Period, Random Allocation, Swine, Flavonoids metabolism, Malus, Polyphenols metabolism
Abstract

Food matrix interactions with polyphenols can affect their bioavailability and as a consequence may modulate their biological effects. The aim of this study was to determine if the matrix and its processing would modulate the bioavailability and the postprandial nutrigenomic response to a dietary inflammatory stress of apple flavan-3-ol monomers. We carried out an acute randomized controlled study in minipigs challenged with a high fat meal (HFM) supplemented with raw fruit, puree, or apple phenolic extract with matched content of flavan-3-ol monomers. Fasting and postprandial blood samples were collected over 3 h to quantify flavan-3-ol monomers in sera by UPLC-Q-TOF/MS and to isolate peripheral blood mononuclear cells (PBMCs) for assessing the changes in the gene expression profile using a microarray analysis. When compared to the extract-supplemented meal, the peak of the total flavan-3-ol concentration was reduced by half with both raw apple and puree supplements. The apple matrices also affected the gene expression profile as revealed by the Principal Component Analysis of the microarray data from PBMCs which discriminated the supplementation of HFM with the polyphenol extract from those with raw apples or puree. A total of 309 genes were identified as differentially expressed by the apple-derived products compared to HFM, with 63% modulated only in the presence of the food matrix (apple and puree). The number of differentially modulated genes was higher with the puree (246) than with the unprocessed apple (182). Pathway enrichment analyses revealed that genes affected by the apple-derived products control inflammation and leukocyte transendothelial migration both involved in the onset of atherosclerotic processes. Overall, this study showed that the two apple matrices reduce the postprandial serum concentration of flavon-3-ols whereas they increase the nutrigenomic response of PBMCs. The biological processes identified as modulated by the apple products suggest an attenuation of the transient pro-inflammatory response induced by a HFM. The differences observed between the nutrigenomic responses support that the apple matrix and its processing affect the nutrigenomic response, probably by increasing the bioavailability of other apple phytochemicals. To conclude, this study raises awareness for considering the impact of the food matrix and its processing on the biological response of polyphenols in nutritional studies.

Published
2020
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48. Curcumin modulates endothelial permeability and monocyte transendothelial migration by affecting endothelial cell dynamics.

Author

Monfoulet LE, Mercier S, Bayle D, Tamaian R, Barber-Chamoux N, Morand C, and Milenkovic D

Subjects
Biomechanical Phenomena, Cell Adhesion drug effects, Coculture Techniques, Cytoskeletal Proteins genetics, Cytoskeletal Proteins metabolism, Diffusion Chambers, Culture, Gene Expression Profiling, Human Umbilical Vein Endothelial Cells cytology, Human Umbilical Vein Endothelial Cells metabolism, Humans, MAP Kinase Kinase Kinases antagonists & inhibitors, MAP Kinase Kinase Kinases chemistry, MAP Kinase Kinase Kinases genetics, Microarray Analysis, Molecular Docking Simulation, NF-kappa B antagonists & inhibitors, NF-kappa B chemistry, NF-kappa B genetics, Permeability drug effects, Protein Serine-Threonine Kinases antagonists & inhibitors, Protein Serine-Threonine Kinases chemistry, Protein Serine-Threonine Kinases genetics, Proto-Oncogene Proteins c-akt antagonists & inhibitors, Proto-Oncogene Proteins c-akt chemistry, Proto-Oncogene Proteins c-akt genetics, Pyruvate Dehydrogenase Acetyl-Transferring Kinase, Rheology, Signal Transduction, THP-1 Cells, Tumor Necrosis Factor-alpha antagonists & inhibitors, Tumor Necrosis Factor-alpha pharmacology, Cell Movement drug effects, Curcumin pharmacology, Gene Expression Regulation drug effects, Human Umbilical Vein Endothelial Cells drug effects
Abstract

Curcumin is a phenolic compound that exhibits beneficial properties for cardiometabolic health. We previously showed that curcumin reduced the infiltration of immune cells into the vascular wall and prevented atherosclerosis development in mice. This study aimed to investigate the effect of curcumin on monocyte adhesion and transendothelial migration (TEM) and to decipher the underlying mechanisms of these actions. Human umbilical vein endothelial cells (HUVECs) were exposed to curcumin (0.5-1μM) for 3h prior to their activation by Tumor Necrosis Factor alpha (TNF-α). Endothelial permeability, monocyte adhesion and transendothelial migration assays were conducted under static condition and shear stress that mimics blood flow. We further investigated the impact of curcumin on signaling pathways and on the expression of genes using macroarrays. Pre-exposure of endothelial cells to curcumin reduced monocyte adhesion and their transendothelial migration in both static and shear stress conditions. Curcumin also prevented changes in both endothelial permeability and the area of HUVECs when induced by TNF-α. We showed that curcumin modulated the expression of 15 genes involved in the control of cytoskeleton and endothelial junction dynamic. Finally, we showed that curcumin inhibited NF-κB signaling likely through an antagonist interplay with several kinases as suggested by molecular docking analysis. Our findings demonstrate the ability of curcumin to reduce monocyte TEM through a multimodal regulation of the endothelial cell dynamics with a potential benefit on the vascular endothelial function barrier., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Published
2017
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49. DHA-derived oxylipins, neuroprostanes and protectins, differentially and dose-dependently modulate the inflammatory response in human macrophages: Putative mechanisms through PPAR activation.

Author

Bosviel R, Joumard-Cubizolles L, Chinetti-Gbaguidi G, Bayle D, Copin C, Hennuyer N, Duplan I, Staels B, Zanoni G, Porta A, Balas L, Galano JM, Oger C, Mazur A, Durand T, and Gladine C

Subjects
Animals, COS Cells, Cells, Cultured, Chlorocebus aethiops, Cytokines genetics, Cytokines metabolism, Dose-Response Relationship, Drug, Drug Evaluation, Preclinical, Gene Expression drug effects, Humans, Lipopolysaccharides pharmacology, Macrophages drug effects, Macrophages metabolism, Anti-Inflammatory Agents pharmacology, Docosahexaenoic Acids pharmacology, Macrophages immunology, Neuroprostanes pharmacology, Oxylipins pharmacology
Abstract

Whereas the anti-inflammatory properties and mechanisms of action of long chain ω3 PUFAs have been abundantly investigated, research gaps remain regarding the respective contribution and mechanisms of action of their oxygenated metabolites collectively known as oxylipins. We conducted a dose-dependent and comparative study in human primary macrophages aiming to compare the anti-inflammatory activity of two types of DHA-derived oxylipins including the well-described protectins (NPD1 and PDX), formed through lipoxygenase pathway and the neuroprostanes (14-A 4t - and 4-F 4t -NeuroP) formed through free-radical mediated oxygenation and expected to be new anti-inflammatory mediators. Considering the potential ability of these DHA-derived oxylipins to bind PPARs and knowing the central role of these transcription factors in the regulation of macrophage inflammatory response, we performed transactivation assays to compare the ability of protectins and neuroprostanes to activate PPARs. All molecules significantly reduced mRNA levels of cytokines such as IL-6 and TNF-α, however not at the same doses. NPD1 showed the most effect at 0.1µM (-14.9%, p<0.05 for IL-6 and -26.7%, p<0.05 for TNF-α) while the three other molecules had greater effects at 10µM, with the strongest result due to the cyclopentenone neuroprostane, 14-A 4t -NeuroP (-49.8%, p<0.001 and -40.8%, p<0.001, respectively). Part of the anti-inflammatory properties of the DHA-derived oxylipins investigated could be linked to their activation of PPARs. Indeed, all tested oxylipins significantly activated PPARγ, with 14-A 4t -NeuroP leading to the strongest activation, and NPD1 and PDX also activated PPARα. In conclusion, our results show that neuroprostanes and more especially cyclopentenone neuroprostanes have potent anti-inflammatory activities similar or even more pronounced than protectins supporting that neuroprostanes should be considered as important contributors to the anti-inflammatory effects of DHA., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Published
2017
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50. Intracerebral γ modulations reveal interaction between emotional processing and action outcome evaluation in the human orbitofrontal cortex.

Author

Jung J, Bayle D, Jerbi K, Vidal JR, Hénaff MA, Ossandon T, Bertrand O, Mauguière F, and Lachaux JP

Subjects
Cerebral Cortex physiology, Epilepsy, Frontal Lobe physiopathology, Epilepsy, Frontal Lobe psychology, Female, Frontal Lobe pathology, Humans, Middle Aged, Brain Waves physiology, Electroencephalography methods, Emotions physiology, Frontal Lobe physiology, Photic Stimulation methods, Psychomotor Performance physiology
Abstract

The orbitofrontal cortex (OFC) plays a key role not only in processing emotions but also in monitoring performance outcome. Although the neuroanatomical substrates underlying each of the two processes have been extensively investigated, they have predominantly been probed separately and therefore a precise knowledge of the functional overlap within the multiple OFC sub-portions involved is still lacking. Here, we explore the neural dynamics mediating performance monitoring and emotional processing using direct intracranial EEG (iEEG) recordings from multiple OFC sites of an epileptic patient. Neural activity was recorded during two experiments. The first task required processing of emotional faces and the second investigated action outcome evaluation based on a visual feedback on the subject's performance. Task-related neural dynamics were assessed using modulations of high frequency responses in the gamma-band (50-150Hz). Our results reveal that processing negative facial emotions as well as receiving negative feedback both elicited gamma-band responses in the lateral OFC. By contrast, the mid-OFC was selectively activated for positive feedback. Furthermore, we also found significant gamma-band deactivation in the gyrus rectus during processing of negative feedback. Our findings provide novel evidence for an intricate valence-selective interaction between the networks mediating emotion processing and performance monitoring in human OFC and support the hypothesis of a tight relationship between gamma-band activity and behavior., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Published
2011
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