Possible intracellular effect of the new water-soluble form of curcumin (NDS27) on the oxidant response of stimulated neutrophils
Derochette, Sandrine ; Mouithys-Mickalad, Ange ; et al
Poster (2012, April 18)
Neutrophils (PMNs) are involved in host defense against infections through the production of reactive oxygen species (ROS) to kill pathologic agents. But, an excessive ROS production, called “oxidative ... [more ▼]
Neutrophils (PMNs) are involved in host defense against infections through the production of reactive oxygen species (ROS) to kill pathologic agents. But, an excessive ROS production, called “oxidative stress” is associated with tissue damages and development of chronic or acute inflammatory diseases. PMNs are prime therapeutic targets to control inflammatory events associated to ROS production. Nowadays, there is a growing interest for the use of polyphenolic molecules to modulate the inflammatory response. The aim of this work was to study the antioxidant effect of NDS27 (1), a new highly water-soluble form of the polyphenolic molecule curcumin, on in vitro stimulated equine PMNs. NDS27 (10-6 to 10-4 M) was pre-incubated with cells and eliminated before their activation. The ability of NDS27 to enter into the cells was checked by HPLC from the cellular extracts. The intracellular ROS production by phorbol myristate acetate (PMA) stimulated PMNs was measured by fluorescence using 2’,7’-dichlorofluorescin diacetate. Lucigenin dependent chemiluminescence was used to measure extracellular ROS production. Additionally, the effect of NDS27 was tested on the activity of myeloperoxidase (MPO), a hemic enzyme contributing to the oxidant response of neutrophils. The activity of the released MPO by cytochalazine B (CB) and N-formyl-methionyl-leucyl-phenylalanine (fMLP) stimulated PMNs was measured by SIEFED (“Specific Immunologic Extraction Followed by Enzymatic Detection”) (2). The HPLC results showed that NDS27 enters into PMNs and interacts with their membrane. NDS27 significantly and dose-dependently inhibited the ROS production in neutrophils without affecting their viability. Likewise, the activity of MPO released by PMNs was lowered by NDS27. Overall, our findings demonstrate that the membrane of neutrophils is permeable to NDS27 or interacts with the drug, suggesting that its inhibitory effect on ROS production is mainly associated to an intracellular effect probably by acting on the enzymes implied in respiratory burst like NADPH oxidase and MPO. The modulatory effect of NDS27 towards the oxidant activity of cells involved in immune and inflammatory response open therapeutic perspectives to control equine or human pathologies with excessive inflammatory reactions. 1. Neven et al. 2011, Patent Application Publication: US2011/0257126 A1 2. Serteyn et al. 2005, European Patent Specification : EP1711817 B1 [less ▲]Detailed reference viewed: 28 (4 ULg)
Systemisch-entzuendliche Reaktion beim Hochleistungssportpferd
Sandersen, Charlotte ; Lejeune, Jean-Philippe ; Votion, Dominique et al
Book published by Leipziger Blaue Hefte (2012)Detailed reference viewed: 25 (6 ULg)
Myeloperoxidase in Equine Semen: Concentration and Localization during Freezing Processing
Ponthier, Jérôme ; ; Franck, Thierry et al
in Journal of Equine Veterinary Science (2012), (32), 32-37
Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutro- phils during degranulation or after lysis. Post-thaw semen contains MPO, and concen- tration of this enzyme is associated ... [more ▼]
Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutro- phils during degranulation or after lysis. Post-thaw semen contains MPO, and concen- tration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozenethawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifuga- tion, and after cooling down to 4 C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4 C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO. [less ▲]Detailed reference viewed: 51 (11 ULg)
Assessment of reactive oxygen species production in cultured equine skeletal myoblasts in response to conditions of anoxia followed by reoxygenation with or without exposure to peroxidases.
Ceusters, Justine ; Mouithys-Mickalad, Ange ; de la Rebière de Pouyade, Geoffroy et al
in American Journal of Veterinary Research (2012), 73(3), 426-434
Objective—To culture equine myoblasts from muscle microbiopsy specimens, examine myoblast production of reactive oxygen species (ROS) in conditions of anoxia followed by reoxygenation, and assess the ... [more ▼]
Objective—To culture equine myoblasts from muscle microbiopsy specimens, examine myoblast production of reactive oxygen species (ROS) in conditions of anoxia followed by reoxygenation, and assess the effects of horseradish peroxidase (HRP) and myeloperoxidase (MPO) on ROS production. Animals—5 healthy horses (5 to 15 years old). Procedures—Equine skeletal myoblast cultures were derived from 1 or 2 microbiopsy specimens obtained from a triceps brachii muscle of each horse. Cultured myoblasts were exposed to conditions of anoxia followed by reoxygenation or to conditions of normoxia (control cells). Cell production of ROS in the presence or absence of HRP or MPO was assessed by use of a gas chromatography method, after which cells were treated with a 3,3′-diaminobenzidine chromogen solution to detect peroxidase binding. Results—Equine skeletal myoblasts were successfully cultured from microbiopsy specimens. In response to anoxia and reoxygenation, ROS production of myoblasts increased by 71%, compared with that of control cells. When experiments were performed in the presence of HRP or MPO, ROS production in myoblasts exposed to anoxia and reoxygenation was increased by 228% and 183%, respectively, compared with findings for control cells. Chromogen reaction revealed a close adherence of peroxidases to cells, even after several washes. Conclusions and Clinical Relevance—Results indicated that equine skeletal myoblast cultures can be generated from muscle microbiopsy specimens. Anoxia-reoxygenation– treated myoblasts produced ROS, and production was enhanced in the presence of peroxidases. This experimental model could be used to study the damaging effect of exercise on muscles in athletic horses. [less ▲]Detailed reference viewed: 53 (27 ULg)
Relationship between exercise-induced systemic inflammatory like reaction and racing performance in endurance horses
Serteyn, Didier ; Caudron, Isabelle ; Lejeune, Jean-Philippe et al
in Comparative Exercise Physiology (2012), 8(3/4), 213218
This study showed that systemic inflammatory like reaction is not clearly related to performance but also to horse-related factors such as intinsic capacity or training.Detailed reference viewed: 22 (8 ULg)
Antioxidant and anti-inflammatory activities of Ribes nigrum extracts.
Tabart, Jessica ; Franck, Thierry ; Kevers, Claire et al
in Food Chemistry (2012), 131(4), 1116-1122
Blackcurrant berries contain high amounts of flavonoids with various health benefits as anti-inflammatory properties attributed to their antioxidant potential. Leaves and buds actually used to produce ... [more ▼]
Blackcurrant berries contain high amounts of flavonoids with various health benefits as anti-inflammatory properties attributed to their antioxidant potential. Leaves and buds actually used to produce food supplement could also exhibit such interesting properties. <br />In the literature, various methods are often used and valid indicators of the antioxidant potential of dietary substances. However these assays do not provide evidence that antioxidants have in vivo or ex vivo activity when consumed. To obtain biologically relevant information, the antioxidant activities of the extracts were evaluated on cellular models implicating the measurement of blood haemolysis, the Cellular Antioxidant Activity on endothelial cells and the anti-inflammatory activities on isolated equine stimulated neutrophils and purified myeloperoxidase. <br />These tests generally showed that the blackcurrant leaf extract have the highest antioxidant and <br />anti-inflammatory (inhibition of MPO activity and ROS production on activated neutrophils) capacities correlated to the highest total phenolics content. [less ▲]Detailed reference viewed: 121 (39 ULg)
Effect of myeloperoxidase and anoxia/reoxygenation on mitochondrial respiratory function of cultured primary equine skeletal myoblasts.
Ceusters, Justine ; Mouithys-Mickalad, Ange ; Franck, Thierry et al
in Mitochondrion (2012)
Horses are particularly sensitive to excessive inflammatory reaction where myeloperoxidase, a marker of inflammation, may contribute to mitochondrial dysfunctions. This study investigated the interaction ... [more ▼]
Horses are particularly sensitive to excessive inflammatory reaction where myeloperoxidase, a marker of inflammation, may contribute to mitochondrial dysfunctions. This study investigated the interaction between myeloperoxidase and cultured primary equine skeletal myoblasts, particularly its effect on mitochondrial respiration combined or not with anoxia followed by reoxygenation (AR). We showed that active myeloperoxidase entered into the cells, interacted with mitochondria and decreased routine and maximal respirations. When combined with AR, myeloperoxidase caused a further decrease of these respiratory parameters while the leak increased. Our results indicate that myeloperoxidase amplifies the mitochondrial damages initiated by AR phenomenon and alters the mitochondrial function. [less ▲]Detailed reference viewed: 27 (11 ULg)
Antioxidant and anti-inflammatory like properties of benzoic acid analogs on the oxidant response of neutrophils: structure/redox potential relationship study.
Franck, Thierry ; Mouithys-Mickalad, Ange ; Robert, Thierry et al
in Free Radical Biology & Medicine (2012), 53(supplement 1),
We investigated the antioxidant capacity of phenolic acid derivatives by measuring their capacity to prevent ABTS oxidation and evaluating their anti-inflammatory like-properties on the oxidant response ... [more ▼]
We investigated the antioxidant capacity of phenolic acid derivatives by measuring their capacity to prevent ABTS oxidation and evaluating their anti-inflammatory like-properties on the oxidant response of neutrophils, especially on superoxide anion production and the activity of myeloperoxidase (MPO), an oxidant enzyme present and released by the primary granules of neutrophils. The superoxide anion production by PMA-stimulated neutrophils was measured by lucigenin-enhanced chimiluminescence (CL) and the activity of MPO by SIEFED to study the potential interaction of a molecule with the enzyme without interferences due to medium. The antioxidant and anti-inflammatory activities of the phenolic compounds were correlated to their redox potentials measured by voltammetry method, and discussed in relation to their molecular structure. The ability of the phenolic molecules to decrease ABTS oxidation and CL production was inversely correlated to their redox potential increasing as follows: propyl gallate > gallic acid > caffeic acid > 3,4-dihydroxybenzoic acid > ferulic acid > syringic acid > 2,6-dihydroxybenzoic acid > salicylic acid > benzoic acid. The number of hydroxyl groups (3) and their position (catechol) were essential for the efficacy of the molecules as stoichiometric antioxidants or scavengers. On MPO activity, the inhibitory capacity of the molecules was not really correlated with their redox potential and increased as follows: gallic acid > caffeic acid > 2,6-dihydroxybenzoic acid > propyl gallate > ferulic acid = syringic acid > 3,4-dihydroxybenzoic acid = salicylic acid > benzoic acid. The number of OH groups and the elongation of the carboxyl group were essential for the inhibition of MPO activity, probably by facilitating the interaction with the MPO active site or structure. The redox potential measurement seems to be a good technique to select stoichiometric antioxidants, but not anti-catalytic ones. [less ▲]Detailed reference viewed: 80 (14 ULg)
Polyphenol Content and Modulatory Activities of Some Tropical Dietary Plant Extracts on the Oxidant Activities of Neutrophils and Myeloperoxidase
Tsumbu, César Ndele ; ; Tits, Monique et al
in International Journal of Molecular Sciences (2012), 13(1), 628-650Detailed reference viewed: 62 (21 ULg)
Antioxidant and Antiradical Activities of Manihot esculenta Crantz (Euphorbiaceae) Leaves and Other Selected Tropical Green Vegetables Investigated on Lipoperoxidation and Phorbol-12-myristate-13-acetate (PMA) Activated Monocytes
Tsumbu, César Ndele ; ; Tits, Monique et al
in Nutrients (2011), 3(9), 818-838
Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae), Manihot esculenta Crantz (Euphorbiaceae) and Pteridium aquilinum (Dennstaedtiaceae) leaves are currently consumed as vegetables by ... [more ▼]
Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae), Manihot esculenta Crantz (Euphorbiaceae) and Pteridium aquilinum (Dennstaedtiaceae) leaves are currently consumed as vegetables by migrants from sub-Saharan Africa living in Western Europe and by the people in the origin countries, where these plants are also used in the folk medicine. Manihot leaves are also eaten in Latin America and some Asian countries. This work investigated the capacity of aqueous extracts prepared from those vegetables to inhibit the peroxidation of a linoleic acid emulsion. Short chain, volatile C-compounds as markers of advanced lipid peroxidation were measured by gas chromatography by following the ethylene production. The generation of lipid hydroperoxides, was monitored by spectroscopy using N-N′-dimethyl-p-phenylene-diamine (DMPD). The formation of intermediate peroxyl, and other free radicals, at the initiation of the lipid peroxidation was investigated by electron spin resonance, using α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as spin trap agent. The ability of the extracts to decrease the cellular production of reactive oxygen species (ROS) in “inflammation like” conditions was studied by fluorescence technique using 2′,7′-dichlorofluorescine-diacetate as fluorogenic probe, in a cell model of human monocytes (HL-60 cells) activated with phorbol ester. Overall the extracts displayed efficient concentration-dependent inhibitory effects. Their total polyphenol and flavonoid content was determined by classic colorimetric methods. An HPLC-UV/DAD analysis has clearly identified the presence of some polyphenolic compounds, which explains at least partially the inhibitions observed in our models. The role of these plants in the folk medicine by sub-Saharan peoples as well as in the prevention of oxidative stress and ROS related diseases requires further consideration. [less ▲]Detailed reference viewed: 211 (9 ULg)
Evaluation of the antioxidant activity of passion fruit (Passiflora edulis and Passiflora alata) extracts on stimulated neutrophils and myeloperoxidase activity assays
; Serteyn, Didier ; et al
in Food Chemistry (2011), 128Detailed reference viewed: 90 (9 ULg)
Specific Immuno Extraction Followed by Enzymatic Detection (SIEFED), a new tool to measure active myeloperoxidase in complex media and to screen potential inhibitors of this enzyme.
Serteyn, Didier ; Mouithys-Mickalad, Ange ; et al
in The 7th International Human Peroxidase Meeting, 22-25 May 2011, Brussels (2011, May 25)
A method called SIEFED (“Specific Immuno Extraction Followed by Enzymatic Detection”) was developed for the specific measurement of myeloperoxidase (MPO) activity without interference of the sample medium ... [more ▼]
A method called SIEFED (“Specific Immuno Extraction Followed by Enzymatic Detection”) was developed for the specific measurement of myeloperoxidase (MPO) activity without interference of the sample medium. In this method, MPO is first extracted out of aqueous or biological samples by its capture by immobilized anti-MPO antibodies. A washing step then allows to eliminate the solution or biological fluid with interfering materials (proteins, lipids, reducing or oxidizing molecules, ...) and in a last step the activity of MPO bound to its antibodies is measured by using a sensitive detection system containing a fluorogenic substrate, hydrogen peroxide and nitrite as reaction enhancer. SIEFED is a method of choice to measure easily, quantitatively, and specifically the active part of MPO present in biological samples or complex media. Results obtained with this technique applied to biological samples emphasize the importance to distinguish the total MPO concentration of a sample obtained by ELISA from the active part of MPO, which is the real witness of the oxidant potential of the enzyme. SIEFED is also a powerful tool to study compounds or natural extracts that could have an inhibitory effect on the activity of MPO. Since the potential inhibitor is first incubated with the enzyme solution, and further eliminated by washing after the immunocapture of MPO, the tested compound or extract cannot interfere with the chromogenic substrate used to measure the activity of MPO or with products derived from the enzyme activity. Thus, an inhibitory effect could only be attributed to a direct interaction of the tested compound with the enzyme, either on the active site or another key position of the structure. In conclusion, the SIEFED technique opens new perspectives to study pathologies in which the release of active MPO is relevant and to select interesting compounds or extracts able to modulate the MPO activity. [less ▲]Detailed reference viewed: 58 (10 ULg)
Effect of benzoic acid analogs on myeloperoxidase activity measured by a new technique to study their direct interaction with the enzyme.
Franck, Thierry ; ; Mouithys-Mickalad, Ange et al
Poster (2011, May)
Myeloperoxidase (MPO) plays a key role in inflammatory response and constitutes a target for new drug development. The effects of some benzoic acid analogs were studied on the specific activity of human ... [more ▼]
Myeloperoxidase (MPO) plays a key role in inflammatory response and constitutes a target for new drug development. The effects of some benzoic acid analogs were studied on the specific activity of human MPO measured by SIEFED (“Specific Immunologic Extraction Followed by Enzymatic Detection”), an original method that consists of incubation of the compound with MPO, followed by capture of the enzyme by specific antibodies, washing (elimination of the compounds) and enzymatic detection of the immunocaptured enzyme. The compounds tested at 10-4, 10-5 and 10-6 M were studied in terms of structure activity relationship. Gallic acid (3,4,5-trihydroxybenzoic acid) with 3 hydroxyl groups had an important dose dependent inhibitory effect on MPO activity. Other molecules with less or without hydroxyl groups [3,4-dihydroxybenzoic acid, 2-hydroxybenzoic acid (salicylic acid) and benzoic acid] had rather an activator effect at 10-5 and 10-6 M. 2,4,6-Trihydroxybenzoic acid, with two hydroxyl groups adjacent to the carboxyl group, had a less efficient inhibitory effect. Caffeic acid (3,4-dihydroxycinnamic acid) with a propenoic acid group presented a dose dependent inhibitory effect on MPO activity contrary to its analog 3,4-dihydroxybenzoic acid. The esterification of the carboxyl group of gallic acid to obtain propyl gallate induced an activation of MPO at 10-5 and 10-6 M. Finally, the substitution of one or two hydroxyl groups by methoxyl ones (ferulic and syringic acids) decreased the efficiency of the molecules on the enzyme inhibition. The SIEFED technique appears as an innovative pharmacological tool to study the direct interaction of compounds with MPO. Number and position of hydroxyl groups and the extension of the carboxyl group of benzoic acid play a crucial role in the inhibition of MPO activity probably by facilitating the interaction with the active site or another elements of the enzyme structure. [less ▲]Detailed reference viewed: 32 (3 ULg)
Flow cytometric detection of myeloperoxidase in horse neutrophils: a novel technique in equine diagnostic research.
; Franck, Thierry ; et al
in Veterinary Immunology and Immunopathology (2011), 144(3-4), 417-22
Myeloperoxidase (MPO) is a protein of interest due to its involvement in equine pathologies. Until now, results in equine diagnostic research were achieved through extracellular MPO detection. However ... [more ▼]
Myeloperoxidase (MPO) is a protein of interest due to its involvement in equine pathologies. Until now, results in equine diagnostic research were achieved through extracellular MPO detection. However, studying the cellular MPO content in neutrophils has revealed important insights in human diseases. This study aimed to develop a technique for the specific detection of MPO on the single cell level defining a flow cytometric protocol for the detection of both equine surface-bound and cellular MPO. Both indirect and direct labeling techniques are described which include the comparison of two secondary antibodies and two linking-fluorochromes, respectively. [less ▲]Detailed reference viewed: 10 (4 ULg)
Clinical significance of active myeloperoxidase in carotid atherosclerotic plaques
GACH, Olivier ; Magne, Julien ; Franck, Thierry et al
in International Journal of Cardiology (2011), 152(1), 149-151Detailed reference viewed: 36 (15 ULg)
Coll2-1, Coll2-1NO2 and myeloperoxidase concentrations in the synovial fluid of equine tarsocrural joints affected with osteochondrosis.
Verwilghen, Denis ; ; et al
in Veterinary Research Communications (2011), 35(7), 401-8
The measurement of biomarkers that reflect cartilage breakdown is a powerful tool for investigating joint damage caused by disease or injury. Particularly in cases of osteochondrosis, synovial ... [more ▼]
The measurement of biomarkers that reflect cartilage breakdown is a powerful tool for investigating joint damage caused by disease or injury. Particularly in cases of osteochondrosis, synovial concentrations of these biomarkers may reveal the presence of osteoarthritic changes. Coll2-1, Coll2-1 NO2 and myeloperoxidase have recently been introduced in equine osteoarticular research but comparison between the concentrations of these markers in OCD affected and healthy joints has not been made. Therefore, this study aimed at reporting the synovial concentrations of these biomarkers in joints affected with osteochondral fragments in the tarsocrural joint compared to unaffected joints. Myeloperoxidase and Coll2-1NO2 revealed to have similar levels between affected joints and controls. However, in contrast to previous studies using C2C the present study demonstrated that synovial levels of Coll2-1 were significantly elevated in tarsocrural joints affected with osteochondrosis. Thus, Coll2-1 may be an earlier marker of cartilage degeneration than other cartilage degradation markers that have been previously used in equine medicine. [less ▲]Detailed reference viewed: 14 (3 ULg)
Relationship between arthroscopic joint evaluation and the levels of Coll2-1, Coll2-1NO(2), and myeloperoxidase in the blood and synovial fluid of horses affected with osteochondrosis of the tarsocrural joint.
Verwilghen, Denis ; ; et al
in Osteoarthritis and Cartilage (2011), 19(11), 1323-9
OBJECTIVE: To evaluate the levels of plasmatic and synovial Coll2-1, Coll2-1NO(2) and myeloperoxidase (MPO) in horses with osteochondral lesions of the tarsocrural joint and to investigate how these ... [more ▼]
OBJECTIVE: To evaluate the levels of plasmatic and synovial Coll2-1, Coll2-1NO(2) and myeloperoxidase (MPO) in horses with osteochondral lesions of the tarsocrural joint and to investigate how these levels relate to arthroscopic findings of inflammation and degeneration. MATERIALS AND METHODS: Venous blood and synovial fluid samples were collected from 63 horses presented for arthroscopic removal of osteochondral fragments in the tarsocrural joint. Prior to removal of the osteochondral fragment, an exploration of the joint was performed and an inflammatory and degenerative score was determined. The blood and synovial levels of Coll2-1, Coll2-1NO(2) and MPO were also measured. The effects of the arthroscopic evaluation (inflammatory and degenerative classes) on the blood and synovial markers were evaluated using a linear model (GLM procedure), and correlations between biochemical markers in the blood and synovial fluid and the arthroscopic evaluation (inflammatory and degenerative classes) were established (Pearson's correlations). RESULTS: Significantly higher levels of Coll2-1 were detected in synovial fluid of higher degenerative classes. There was a significant correlation between the degenerative score and the synovial levels of Coll2-1 (r=0.27). According to the logistic regression model, there was a significant effect of the degenerative class on synovial levels of Coll2-1. CONCLUSIONS: Coll2-1 correlates well with the degenerative state of tarsocrural joints as evaluated by arthroscopy. This marker can therefore be classified as a burden-of-disease marker in the assessment of joint disease in horses. [less ▲]Detailed reference viewed: 22 (8 ULg)
Inhalation with NDS27 attenuates pulmonary neutrophilic inflammation in recurrent airway obstruction
Sandersen, Charlotte ; ; Franck, Thierry et al
in Veterinary Record : Journal of the British Veterinary Association (2011)Detailed reference viewed: 49 (22 ULg)
Do polyamines increase the antioxidant capacity of hyperhydric shoots ?
Franck, Thierry ; Tabart, Jessica ; Kevers, Claire et al
in 4th international workshop - cost action FA0605 - Book of abstracts - Limassol 17-19 November (2011)Detailed reference viewed: 20 (3 ULg)
Benefits of napping and an extended duration of recovery sleep on alertness and immune cells after acute sleep restriction.
; ; et al
in Brain, Behavior & Immunity (2011), 25(1), 16-24
Understanding the interactions between sleep and the immune system may offer insight into why short sleep duration has been linked to negative health outcomes. We, therefore, investigated the effects of ... [more ▼]
Understanding the interactions between sleep and the immune system may offer insight into why short sleep duration has been linked to negative health outcomes. We, therefore, investigated the effects of napping and extended recovery sleep after sleep restriction on the immune and inflammatory systems and sleepiness. After a baseline night, healthy young men slept for a 2-h night followed by either a standard 8-h recovery night (n=12), a 30-min nap (at 1 p.m.) in addition to an 8-h recovery night (n=10), or a 10-h extended recovery night (n=9). A control group slept 3 consecutive 8-h nights (n=9). Subjects underwent continuous electroencephalogram polysomnography and blood was sampled every day at 7 a.m. Leukocytes, inflammatory and atherogenesis biomarkers (high-sensitivity C-reactive protein, interleukin-8, myeloperoxidase, fibrinogen and apolipoproteins ApoB/ApoA), sleep patterns and sleepiness were investigated. All parameters remained unchanged in the control group. After sleep restriction, leukocyte and - among leukocyte subsets - neutrophil counts were increased, an effect that persisted after the 8-h recovery sleep, but, in subjects who had a nap or a 10-h recovery sleep, these values returned nearly to baseline. Inflammatory and atherogenesis biomarkers were unchanged except for higher myeloperoxidase levels after sleep restriction. The increased sleepiness after sleep restriction was reversed better in the nap and extended sleep recovery conditions. Saliva cortisol decreased immediately after the nap. Our results indicate that additional recovery sleep after sleep restriction provided by a midday nap prior to recovery sleep or a sleep extended night can improve alertness and return leukocyte counts to baseline values. [less ▲]Detailed reference viewed: 24 (2 ULg)