References of "Franck, Thierry"
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See detailCombined method for the sequential measurement of (1) the enzymatically active fraction and (2) the total amount of an enzyme
Serteyn, Didier ULg; Deby-Dupont, Ginette; Franck, Thierry ULg et al

Patent (2009)

The present invention is related to a combined method and kit (or device) for the sequential measurement of the enzymatically active fraction and the total amount of an enzyme [(such as myeloperoxidase ... [more ▼]

The present invention is related to a combined method and kit (or device) for the sequential measurement of the enzymatically active fraction and the total amount of an enzyme [(such as myeloperoxidase (MPO)] in a sample, and that find improved applications in veterinary and human health fields. [less ▲]

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See detailRelationship between biochemical markers and radiographic scores in the evaluation of the osteoarticular status of Warmblood stallions
Verwilghen, Denis ULg; Busoni, Valeria ULg; Gangl, Monika et al

in Research in Veterinary Science (2009), 87(2), 319-28

Establishing the osteoarticular status of the horse is often performed by means of radiological screening of the animals. Widespread blood sampling could reveal to be an interesting alternative to this ... [more ▼]

Establishing the osteoarticular status of the horse is often performed by means of radiological screening of the animals. Widespread blood sampling could reveal to be an interesting alternative to this procedure which is time consuming and sometimes technically difficult. The aim of this study was to investigate the relationship between the radiological status of the horses and the levels of biochemical markers of cartilage degradation and synovial inflammation. A specific radiological scoring and classification system was therefore developed and applied on 63 stallions presented for studbook admission. Additionally, groups of horses were established according to the occurrence of osteochondrosis, degenerative joint disease and distal interphalangeal joint effusion. Insulin growth factor-I, myeloperoxidases, Coll2-1 and Coll2-1NO(2) were used as blood markers. The combination of the blood parameters did not seem to correlate with the used scoring system. Coll2-1NO(2) levels however tended to increase with poorer radiological class and this could therefore potentially be a useful predictor of the osteoarticular status in the horse. Coll2-1 levels were significantly higher in the degenerative joint disease group. A high percentage of horses with distal interphalangeal joint effusion was present in this study and was associated with decreased IGF-I and increased Coll2-1 levels. [less ▲]

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See detailA new easy method for specific measurement of active myeloperoxidase in human biological fluids and tissue extracts
Franck, Thierry ULg; Kohnen, Stephan; Zouaoui Boudjeltia, Karim et al

in Talanta (2009), 80

The SIEFED (“Specific Immunological Extraction Followed by Enzymatic Detection”) method already developed for the specific detection of the activity of equine myeloperoxidase (MPO) was adapted for the ... [more ▼]

The SIEFED (“Specific Immunological Extraction Followed by Enzymatic Detection”) method already developed for the specific detection of the activity of equine myeloperoxidase (MPO) was adapted for the specific measurement of active human MPO in biological fluids or tissue extracts. [less ▲]

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See detailEquine neutrophil elastase in plasma, laminar tissue, and skin of horses administered black walnut heartwood extract.
de la Rebière de Pouyade, Geoffroy ULg; Riggs, L. M.; Moore, J. N. et al

in Veterinary immunology and immunopathology (2009)

Laminitis is a local manifestation of a systemic inflammatory response that is characterized by neutrophil activation and movement of neutrophils into the laminar tissues. Given the evidence for the ... [more ▼]

Laminitis is a local manifestation of a systemic inflammatory response that is characterized by neutrophil activation and movement of neutrophils into the laminar tissues. Given the evidence for the involvement of neutrophils in the development of laminitis, we measured concentrations of neutrophil elastase, a serine protease released from the azurophilic granules of neutrophils, in plasma, skin and laminar tissues obtained from control horses and horses given black walnut heartwood extract (BWHE) to induce laminitis. Healthy horses (5-15 years old) were randomly assigned to 4 groups: 3 experimental groups given BWHE via nasogastric tube, and a control group given an equal volume of water. The experimental groups consisted of horses euthanized 1.5h (n=5), 3h (n=6) or 12h (n=10) after BWHE administration. Control horses (n=7) were euthanized 12h after intragastric administration of water. Plasma samples were collected in all horses of the control and 12h BWHE groups at 0, 1, 2, 3, 4, 6, 8, 10, and 12h after treatment, and laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia in all 1.5 and 3h BWHE horses, in 6 of the 12h BWHE horses and in 5 of the control horses. Plasma and tissue concentrations of neutrophil elastase were determined using an equine specific ELISA, and statistical significance was set at p<0.05. Plasma concentrations of neutrophil elastase in the BWHE group were significantly higher at 6 and 8h compared to the control group and at 8 and 10h compared to time 0. Concentrations of neutrophil elastase in skin and laminar tissue were significantly higher in the 3 and 12h BWHE groups compared to the control group. Concentrations of neutrophil elastase were significantly higher in the skin than in the lamina in the 12h BWHE horses. The administration of BWHE thus results in significant increases in the concentration of neutrophil elastase in the circulation, skin and laminar tissue. These results confirm a role for neutrophils in the developmental phase of laminitis, and the systemic nature of the inflammatory process. Furthermore, neutrophil elastase may play a key role in the disintegration of the hoof basal membrane and be a target for the development of new treatments for laminitis. [less ▲]

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See detailActivation of equine neutrophils by phorbol myristate acetate or N-formyl-methionyl-leucyl-phenylalanine induces a different response in reactive oxygen species production and release of active myeloperoxidase.
Franck, Thierry ULg; Kohnen, Stéphane; de la Rebière de Pouyade, Geoffroy ULg et al

in Veterinary Immunology and Immunopathology (2009)

Neutrophil (PMN) contribution to the acute inflammatory processes may lead to an excessive generation of reactive oxygen metabolites species (ROS) and secretion of granule enzymes. We compared the effects ... [more ▼]

Neutrophil (PMN) contribution to the acute inflammatory processes may lead to an excessive generation of reactive oxygen metabolites species (ROS) and secretion of granule enzymes. We compared the effects of either phorbol myristate acetate (PMA) or N-formyl-methionyl-leucyl-phenylalanine (fMLP) in combination with a pre-treatment by cytochalasin B (CB) on the production of ROS and the release of total and active myeloperoxidase (MPO) by isolated equine PMNs. The ROS production was assessed by lucigenin dependent chemiluminescence (CL) and ethylene release by alpha-keto-gamma-methylthiobutyric acid (KMB) oxidation. In the supernatant of activated PMNs, total equine MPO was measured by ELISA and active MPO by the SIEFED (Specific Immunologic Extraction Followed by Enzymatic Detection) technique that allows for the study of the interaction of a compound directly with the enzyme. The stimulation of PMNs with CB-fMLP only modestly increased the release of MPO, but more than 70% of released MPO was active. PMA stimulation markedly increased the production of ROS and release of MPO, but more than 95% of released MPO was inactive. When PMNs were pre-incubated with superoxide dismutase (SOD) prior to PMA activation, the lucigenin enhanced CL, which is linked to the superoxide anion (O(2)(-)) production, was much more decreased than KMB oxidation, linked to the hydroxyl-like radical production. The addition of SOD prior to the activation of PMNs by PMA also limited the loss of the activity of released MPO. These results confirm the key role of O(2)(-) generation in the ROS cascade in PMN and reveal its critical role on MPO inactivation. [less ▲]

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See detailVariations of plasmatic concentrations of Insulin-like Growth Factor-I in post-pubescent horses affected with developmental osteochondral lesions.
Verwilghen, Denis ULg; Vander Heyden, Laurent ULg; Franck, Thierry ULg et al

in Veterinary Research Communications (2009)

Developmental osteochondral lesions are often encountered in the equine population and are a major cause of lameness. Different growth factors that act systemically as well as locally regulate the growth ... [more ▼]

Developmental osteochondral lesions are often encountered in the equine population and are a major cause of lameness. Different growth factors that act systemically as well as locally regulate the growth of cartilage. Among them is Insulin-like Growth Factor I that has been demonstrated to promote chondrocyte growth and differentiation and that has been shown to influence cartilage repair. The aims of this study were to investigate differences in circulating plasma levels of Insulin-like Growth Factor-I in post-pubescent horses affected with developmental osteochondral lesions compared to unaffected ones. Significantly higher values of circulating Insulin-like Growth Factor-I levels were found in the affected group (n = 82) compared to controls (n = 86). This result may still reflect an earlier imbalance in IGF-I levels from horses with developmental osteochondral lesions considering the aetiopathological link which has been made between IGF-I and the occurrence of osteochondrosis. However, other studies have shown increased expression of IGF-I after cartilage damage. The higher levels found in this study could be due to a healing response of the cartilage to the damage caused by the osteochondral lesions. [less ▲]

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See detailEffect de l'entraînement sur la fonction mitochondriale musculaire du cheval d'endurance
Votion, Dominique ULg; Fraipont, Audrey ULg; Franck, Thierry ULg et al

in 35eme Journee de la Recherche Equine, jeudi 26 fevrier 2009, Paris, France (2009)

Athletic ability of endurance horses is intimately linked to muscle oxidative capacity. Microbiopsies of triceps brachii (TB) and gluteus medius (GM) were collected before and after 10 weeks of training ... [more ▼]

Athletic ability of endurance horses is intimately linked to muscle oxidative capacity. Microbiopsies of triceps brachii (TB) and gluteus medius (GM) were collected before and after 10 weeks of training in 7 endurance horses to assess the feasibility of studying training effect with the use of microbiopsies. Oxygen consumption of permeabilized fibers was evaluated by high resolution respirometry (HRR) with a titration protocol that defines the activity of the mitochondrial complexes. Differences among muscles before and after training as well as training effect were assessed by Wilcoxon matched pairs test (P<0.05). No complications occurred following microbiopsies in any horse. The in situ oxidative capacity of the TB and GM increased with training. No difference was found between the TB and GM when one horse was excluded from the statistical analysis. Indeed, this horse showed signs of exercise intolerance before sampling (after the training period) which were associated to a low rate of respiration in GM but not in TB. Results of this study showed that HRR may be used to follow training effect and suggest that metabolic impairment might be detected with HRR. [less ▲]

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See detailIn vivo administration of acepromazine or promethazine to horse decreases the reactive oxygen species production response of subsequently isolated neutrophils to stimulation with phorbol myristate acetate
Péters, Fabrice; Franck, Thierry ULg; Pequito, Manuel et al

in Journal of Veterinary Pharmacology & Therapeutics (2009)

The previous experiments have shown that some phenothiazines have antioxidant and anti-inflammatory properties in vitro. In this study the inhibition of the production of reactive oxygen species (ROS) by ... [more ▼]

The previous experiments have shown that some phenothiazines have antioxidant and anti-inflammatory properties in vitro. In this study the inhibition of the production of reactive oxygen species (ROS) by neutrophils was studied in two groups of horses, which received a dose of 0.1 mg⁄ kg of either acepromazine or promethazine intravenously. Blood samples were collected before (T0) and 0.5, 1, 3 and 5 h after drug administration. The chemiluminescence (CML) response of neutrophils was measured ex vivo in the presence of luminol for a period of 10 min and the maximum CML value (peak value) recorded. There was a significant inhibition of the ROS production in the acepromazine treated group (49% inhibition) at 5 h after administration and in the promethazine group (24% inhibition) at 3 h after administration (P < 0.05 vs. T0). These findings are of therapeutic relevance in the use of phenothiazines in equine patients with inflammatory diseases where neutrophil activation and ROS production are implicated. [less ▲]

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See detailMethod for co-purification of equine neutrophil elastase and myeloperoxidase from a limited blood volume.
de la Rebière de Pouyade, Geoffroy ULg; Serteyn, Didier ULg; Deby, Ginette ULg et al

in Research in Veterinary Science (2009)

Neutrophil myeloperoxidase (MPO) and elastase can be released in severe inflammatory diseases and cause tissue injuries. Equine enzymes have already been individually purified from large blood quantities ... [more ▼]

Neutrophil myeloperoxidase (MPO) and elastase can be released in severe inflammatory diseases and cause tissue injuries. Equine enzymes have already been individually purified from large blood quantities. We describe the isolation of both enzymes from a same limited blood volume. Both MPO and elastase were extracted by crushing PMN isolated by centrifugation on a percoll-gradient from a 460ml blood collection. MPO and elastase were separated by an ionic exchange chromatography phase and further purified by gel filtration chromatography on Superdex 200 and 75, respectively. Enzymes were identified in the collected fractions by specific enzymatic assays. The final purity was verified by electrophoresis. Specific activity was improved to 19.92 and 34.3x for elastase (final yield: 340mug) and MPO (final yield: 130mug), respectively, during the procedure. Results show the possibility of isolating both enzymes from the same blood sample with a sufficient yield and purity for future studies on their implication and interaction during inflammatory diseases. [less ▲]

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See detailLes nouveaux outils d’investigation des myopathies « typiques » et atypique.
Votion, Dominique ULg; van Galen, Gaby; Deby-Dupont, Ginette et al

(2008, October)

This paper aims at describing new investigation tools that are currently under development. Oxymetry, electron spin resonance and myeloperoxidase assays may be applied on muscle sample taken by ... [more ▼]

This paper aims at describing new investigation tools that are currently under development. Oxymetry, electron spin resonance and myeloperoxidase assays may be applied on muscle sample taken by microbiopsy as well as on culture of myocytes. In a next future, these tools should improve our knowledge of the pathophysiological mechanisms involved in clinical and subclinical equine myopathies. [less ▲]

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See detailEquine frozen semen parameters in relation with total myeloperoxidase concentration
Ponthier, Jérôme ULg; Franck, Thierry ULg; Mottart, Evelyne et al

in Animal Reproduction Science (2008, September 15)

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See detailMyeloperoxidase Assay in Plasma and Peritoneal Fluid of Horses with Gastrointestinal Disease
Grulke, Sigrid ULg; Franck, Thierry ULg; Gangl, Monika et al

in Canadian Journal of Veterinary Research = Revue Canadienne de Recherche Vétérinaire (2008), 72(1), 37-42

Gastrointestinal disorders, especially strangulating intestinal obstructions, are still a major cause of illness and death in the horse. Circulating lipopolysaccharides may activate both neutrophils and ... [more ▼]

Gastrointestinal disorders, especially strangulating intestinal obstructions, are still a major cause of illness and death in the horse. Circulating lipopolysaccharides may activate both neutrophils and monocytes. The activated neutrophils release myeloperoxidase (MPO), a specific enzyme with strong oxidative activity. The aim of this study was to evaluate MPO concentrations in the plasma and peritoneal fluid (PF) of horses with colic and to check the hypothesis that these concentrations would be higher in a case of strangulating obstruction than in cases of nonstrangulating disease. By using a specific enzyme-linked immunosorbent assay for equine MPO, we determined the MPO concentrations in horses admitted to a clinic for colic. Horses with nonstrangulating or strangulating obstruction of the large intestine (NSLI or SLI), strangulating obstruction of the small intestine (SSI), or inflammatory bowel disease (IBD) were compared with healthy horses. The horses with SLI, SSI, or IBD had significantly higher MPO levels in plasma and PF than did those in the other 2 groups. The mean plasma level was significantly higher in the horses with NSLI than in the healthy horses. High MPO values in PF indicated necrotic bowel. These results show that neutrophil activation occurs during nonstrangulating and strangulating intestinal obstruction in horses and that the plasma and PF MPO concentrations may be a marker of the severity of the disease. [less ▲]

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See detailInhibitory effect of curcuminoids and tetrahydrocurcuminoids on equine activated neutrophils and myeloperoxidase activity
Franck, Thierry ULg; Kohnen, Stephan ULg; Grulke, Sigrid ULg et al

in Physiological Research (2008), 57(4), 577-587

In the horse, the inflammation response to various pathologies (intestinal strangulations, laminitis, etc.) involves an excessive stimulation of the polymorphonuclear neutrophils releasing reactive oxygen ... [more ▼]

In the horse, the inflammation response to various pathologies (intestinal strangulations, laminitis, etc.) involves an excessive stimulation of the polymorphonuclear neutrophils releasing reactive oxygen species (ROS) and myeloperoxidase (MPO). The aim of the present work was to study the effect of natural polyphenols, curcuminoids and tetrahydrocurcuminoids (THC) on isolated stimulated equine neutrophils and on the activity of purified MPO. The ROS production and the release of MPO by activated neutrophils were measured by chemiluminescence and ELISA techniques, respectively. The activity of purified MPO was measured by studying its nitration, chlorination or oxidation capacity and by using an original method called SIEFED allowing the study of drug interaction with the enzyme without interferences of the medium. Curcuminoids and THC had dose-dependent inhibitory effects on ROS production and MPO release by activated neutrophils and on purified MPO activity. We suggest that the higher efficacy of curcuminoids versus THC could be explained, at least partially, by its chemical structure: the conjugated double bounds and the plane structure of curcuminoids made easier the neutralization of the radical species generated by activated neutrophils and the interaction of the drug with the active site of MPO. These inhibitory effects of curcuminoids on the oxidant activity of equine neutrophils and on MPO activity open therapeutic perspectives in equine pathologies with excessive inflammatory reactions. [less ▲]

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See detailEffects of Unfractionated and Fractionated Heparins on Myeloperoxidase Activity and Interactions with Endothelial Cells: Possible Effects on the Pathophysiology of Equine Laminitis
de la Rebière de Pouyade, Geoffroy ULg; Franck, Thierry ULg; Dupont, Ginette ULg et al

in Veterinary Journal (2007), 178(1), 62-69

As heparins are sometimes used to prevent equine laminitis, the interactions between equine neutrophil myeloperoxidase (MPO), unfractionated (UFH) and fractionated low molecular weight (LMWH) heparins and ... [more ▼]

As heparins are sometimes used to prevent equine laminitis, the interactions between equine neutrophil myeloperoxidase (MPO), unfractionated (UFH) and fractionated low molecular weight (LMWH) heparins and digital endothelium have been investigated. The effects of the heparins on purified equine MPO activity were tested by immunocapture followed by enzymatic detection. Endothelium-MPO interactions were assessed by measuring total and active MPO uptake by arterial and venous digital endothelial cells in culture with or without the addition of heparins. A dose-dependent MPO inhibition by UFH and LMWH was seen, with the greatest reduction in MPO activity noted with the highest concentration of LMWH. The MPO capture was greater in arterial cells, but heparins better inhibited MPO capture in venous cells. The activity of cell-bound MPO was almost completely suppressed by the heparins, and no differences were observed between UFH and LMWH. The results confirm the anti-inflammatory properties of heparins and allow a better understanding of the potential role of MPO in laminitis. [less ▲]

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See detailResveratrol inhibits the activity of equine neutrophil Myeloperoxidase by a direct interaction with the enzyme
Kohnen, Stephan ULg; Franck, Thierry ULg; Van Antwerpen, Pierre et al

in Journal of Agricultural and Food Chemistry (2007), 55(20), 8080-8087

Resveratrol is a polyphenolic antioxidant present in beverage and food known for its multiple protective effects. We report the inhibitory effects of resveratrol on equine myeloperoxidase (MPO), a hemic ... [more ▼]

Resveratrol is a polyphenolic antioxidant present in beverage and food known for its multiple protective effects. We report the inhibitory effects of resveratrol on equine myeloperoxidase (MPO), a hemic peroxidase present in the granules of the neutrophils involved in the inflammatory response. Resveratrol inhibited the production of reactive oxygen species (ROS) by stimulated equine neutrophils by acting as a direct scavenger of the ROS released by the cells but did not modify the degranulation of the stimulated neutrophils as the amounts of released MPO were unchanged. Resveratrol strongly inhibited the chlorination, oxidation, and nitration activities of MPO in a dose-dependent manner. By an original technique of specific immunological extraction followed by enzymatic detection (SIEFED), we demonstrated that resveratrol inhibited the peroxidasic activity of the MPO measured by a direct interaction such as the fixation of resveratrol on the enzyme. The observation of a decrease of the accumulation of compound II suggested that resveratrol acts as an electron donor for MPO reduction. [less ▲]

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See detailPlasma concentration of insulin-like growth factor I (IGF-I) in growing Ardenner horses suffering from juvenile digital degenerative osteoarthropathy
Lejeune, Jean-Philippe ULg; Franck, Thierry ULg; Gangl, Monika et al

in Veterinary Research Communications (2007), 31(2), 185-195

Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to ... [more ▼]

Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to affect the anabolism of cartilage matrix molecules. A group of 30 Ardenner horses reared under standardized conditions from weaning were evaluated periodically from 15 to 28 months of age to detect the early manifestations of the disease. At the end of this period, horses were classified in two pathological groups related to the degree of interphalangeal degenerative osteoarthropathy based on clinical and radiographic evaluations: healthy (46.7%) and pathological (53.3%) horses. Seven sequential blood samples were taken from each horse (during the evaluation period) to study the variation of IGF-I plasma concentration. We tested the variations of the IGF-I plasma concentration during growth, and the effect of sex and of pathological classes. Significant variations were observed during the research period, with a maximum value corresponding to spring and a minimum in autumn. A significant reduction of the IGF-I plasma concentration was also observed in the pathological horses (433.5 +/- 19.5 ng/ml) compared to the healthy horses (493.9 +/- 18.2 ng/ml). An alteration in the level of this growth factor could induce a disregulation of the mechanisms involved in the local control of joint and bone tissue development. [less ▲]

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See detailNeutrophil myeloperoxidase measurements in plasma, laminar tissue, and skin of horses given black walnut extract
Riggs, L. M.; Franck, Thierry ULg; Moore, J. N. et al

in American Journal of Veterinary Research (2007), 68(1), 81-86

Objective-To compare measurements of myeloperoxidase (MPO) in plasma, laminar tissues, and skin obtained from control horses and horses given black walnut heartwood extract (BWHE). Animals-22 healthy 5 ... [more ▼]

Objective-To compare measurements of myeloperoxidase (MPO) in plasma, laminar tissues, and skin obtained from control horses and horses given black walnut heartwood extract (BWHE). Animals-22 healthy 5- to 15-year-old horses. Procedures-Horses were randomly assigned to 4 groups as follows: a control group given water (n = 5) and 3 experimental groups given BWHE (17) via nasogastric intubation Experimental groups consisted of 5, 6, and 6 horses that received BWHE and were euthanatized at 1.5, 3, and 12 hours after intubation, respectively. Control horses were euthanatized at 12 hours after intubation. Plasma samples were obtained hourly for all horses. Laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia. Plasma and tissue MPO concentrations were determined via an ELISA; tissue MPO activity was measured by use of specific immunologic extraction followed by enzymatic detection. Results-Tissues and plasma of horses receiving BWHE contained significantly higher concentrations of MPO beginning at hour 3. Laminar tissue and skin from horses in experimental groups contained significantly higher MPO activity than tissues from control horses. Concentrations and activities of MPO in skin and laminar tissues were similar over time. Conclusions and Clinical Relevance-in horses, BWHE administration causes increases in MPO concentration and activity in laminar tissue and skin and the time of increased MPO concentration correlates with emigration of WBCs from the vasculature. These findings support the hypothesis that activation of peripheral WBCs is an early step in the pathogenesis of acute laminitis. [less ▲]

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See detailAre COX-2 Inhibitors Active on Intracellular Oxidative Processes? A Study on In Vitro and Cellular Models
Mouithys-Mickalad, Ange ULg; Deby-Dupont, Ginette; Deby, Carol et al

Book published by Nova Science Publishers, Inc. (2006)

In the last years, there has been an increasing interest of using cyclooxygenase-2 (COX-2) inhibitors to treat the inflammatory pain and chronic inflammatory diseases such as osteoarthritis and rheumatoid ... [more ▼]

In the last years, there has been an increasing interest of using cyclooxygenase-2 (COX-2) inhibitors to treat the inflammatory pain and chronic inflammatory diseases such as osteoarthritis and rheumatoid arthritis. The beneficial effects were to avoid the secondary adverse effects such as bleeding and gastric irritation, generally observed with aspirin and conventional NSAIDs. COX-1 is constitutively expressed in most tissues and involved in the regulation of normal homeostatic functions, while COX-2 is not detected in most tissues but induced by inflammatory stimuli. These outcomes motivated the commercial development of selective COX-2 inhibitors. Recent data suggested that the COX-2 enzyme can be expressed within atherosclerotic lesions and could play a crucial role in various types of cancers, by the way of its activity on the ROS production, gene transcription and prostaglandin (PGE2) production. Consequently, the COX-2 enzyme has become a real target for the study of various classes of compounds and specially the possible additional properties of COX-2 inhibitors. We and other groups have already investigated the pro or antioxidant profile of conventional NSAIDs and some COX-2 inhibitors. With the recent withdrawal of two compounds of the coxib’s family (rofecoxib and celecoxib), for adverse cardiovascular events, concerns regarding the safety of all COX-2 inhibitors have been raised. To answer to these concerns, different approaches were developed by studying on in vitro models, the potential inhibiting-or-stimulating activities on oxidative phenomena of new drugs with already recognized therapeutic effects. Preliminary data obtained with COX-2 inhibitors showed a moderate inhibiting effect on the intracellular oxidant processes and others a stimulating activity. New hypotheses for the treatment of inflammation are now suggested for compounds like nimesulide and its analogous, which are selective towards COX-2 with little activity on COX-1. Here, we reported the in vitro effects of some Cox-2 inhibitors, in comparison with traditional drugs (ibuprofen, diclofenac and aceclofenac) by using two cellular models: a human lung type II alveolar cell line (A549) and a human promonocyte cell line (THP-1). The direct interactions between the drugs and ROS were also investigated in cell-free systems. [less ▲]

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