References of "Oprenyeszk, Frédéric"
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See detailDes champignons contre l'arthrose
Henrotin, Yves ULg; Oprenyeszk, Frédéric ULg

Article for general public (2016)

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See detailGuérir l'arthrose grâce au champignon de Paris
Henrotin, Yves ULg; Oprenyeszk, Frédéric ULg

Article for general public (2016)

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See detailMise au point d'un biomatériau à base de chitosan pour le traitement de l'arthrose
Oprenyeszk, Frédéric ULg

Doctoral thesis (2015)

L'arthrose est une pathologie dont la prévalence est élevée avec un retentissement socioéconomique important. À ce jour, les traitements de l’arthrose sont essentiellement symptomatiques. Le remplacement ... [more ▼]

L'arthrose est une pathologie dont la prévalence est élevée avec un retentissement socioéconomique important. À ce jour, les traitements de l’arthrose sont essentiellement symptomatiques. Le remplacement de l'articulation arthrosique par une prothèse est réservé aux formes les plus évoluées de la maladie. Dans ce contexte, il existe un réel besoin de nouveaux traitements bien tolérés et capables de prévenir ou de retarder la progression de la maladie. Dans ce but, nous avons développé des nouveaux biomatériaux sous la forme de billes ou d'hydrogel composés de chitosan d'origine non animale. Dans la première partie de ce travail, nous avons étudié in vitro le comportement des chondrocytes humains, provenant de cartilage arthrosique, incorporés dans des billes de chitosanalginate. Nous avons mesuré la quantité de médiateurs pro-infl ammatoires, cataboliques et anaboliques produite par les chondrocytes. Dans la deuxième partie, nous avons étudié les effets des billes de chitosan-alginate, injectées dans l’articulation, sur la progression de l’arthrose induite chez le lapin par section du ligament croisé antérieur. In vitro, nous avons mis en évidence les effets bénéfi ques et prometteurs des billes de chitosanalginate sur le métabolisme des chondrocytes humains arthrosiques. Dans ces conditions, ils produisaient moins de médiateurs infl ammatoires et cataboliques tout en maintenant la synthèse de composants spécifi ques de la matrice du cartilage. L'étude chez le lapin a montré que l’injection des billes de chitosan-alginate dispersées dans un hydrogel de chitosan prévenait le pincement de l’interligne articulaire - évalué sur une radiographie standard - et réduisait de façon signifi cative la gravité des lésions histologiques du cartilage ainsi que la synovite. En conclusion, la bille de chitosan-alginate est une matrice intéressante pour la thérapie cellulaire des lésions du cartilage et représente une alternative à l’acide hyaluronique pour la viscosupplémentation. [less ▲]

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See detailChitosan enriched three-dimensional matrix reduces inflammatory and catabolic mediators production by human chondrocytes
Oprenyeszk, Frédéric ULg; Sanchez, Christelle ULg; Dubuc, Jean-Emile et al

in PLoS ONE (2015), 10(5),

This in vitro study investigated the metabolism of human osteoarthritic (OA) chondrocytes encapsulated in a spherical matrix enriched of chitosan. Human OA chondrocytes were encapsulated and cultured for ... [more ▼]

This in vitro study investigated the metabolism of human osteoarthritic (OA) chondrocytes encapsulated in a spherical matrix enriched of chitosan. Human OA chondrocytes were encapsulated and cultured for 28 days either in chitosan-alginate beads or in alginate beads. The beads were formed by slowly passed dropwise either the chitosan 0.6%- alginate 1.2% or the alginate 1.2% solution through a syringe into a 102 mM CaCl2 solution. Beads were analyzed histologically after 28 days. Interleukin (IL)-6 and -8, prostaglandin (PG) E2, matrix metalloproteinases (MMPs), hyaluronan and aggrecan were quantified directly in the culture supernatant by specific ELISA and nitric oxide (NO) by using a colorimetric method based on the Griess reaction. Hematoxylin and eosin staining showed that chitosan was homogeneously distributed through the matrix and was in direct contact with chondrocytes. The production of IL-6, IL-8 and MMP-3 by chondrocytes significantly decreased in chitosan-alginate beads compared to alginate beads. PGE2 and NO decreased also significantly but only during the first three days of culture. Hyaluronan and aggrecan production tended to increase in chitosan-alginate beads after 28 days of culture. Chitosan-alginate beads reduced the production of inflammatory and catabolic mediators by OA chondrocytes and tended to stimulate the synthesis of cartilage matrix components. These particular effects indicate that chitosan-alginate beads are an interesting scaffold for chondrocytes encapsulation before transplantation to repair cartilage defects. [less ▲]

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See detailPrevention of Synovial Membrane Inflammation & Cartilage Degradation by a Novel Chitosan
Henrotin, Yves ULg; Oprenyeszk, Frédéric ULg; Dubuc, Jean-Emile et al

Conference (2015, May 10)

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See detailDevelopment and evaluation in vitro and in vivo of injectable hydrolipidic gels with sustained-release properties for the management of articular pathologies such as osteoarthritis.
Réeff, Jonathan; Oprenyeszk, Frédéric ULg; Franck, Thierry ULg et al

in International Journal of Pharmaceutics (2015), 490

This study aimed to evaluate glycerol monooleate (GMO) as a carrier to develop viscoelastic and injectable sustained-release drug delivery systems. The potential pro- and antioxidant activity of the ... [more ▼]

This study aimed to evaluate glycerol monooleate (GMO) as a carrier to develop viscoelastic and injectable sustained-release drug delivery systems. The potential pro- and antioxidant activity of the developed hydrolipidic gels were evaluated by measuring the production of ROS by polymorphonuclear leukocytes (PMNs). In addition, the biocompatibility and effectiveness of two selected gel candidates were evaluated in vivo by evaluating the benefit of a single intraarticular injection of these new treatments in a model of osteoarthritis in rabbits. The in vitro study demonstrated that the carrier F1 did not have a pro-oxidative effect and even protected PMNs against natural auto-activation, regardless of the incorporation of either clonidine chlorhydrate or betamethasone dipropionate. The in vivo study demonstrated that F1 and F1-BDP induced a loss of cartilage quality in comparison to the control and reference groups but that the lesions of cartilage observed were generally mild, with not much full-depth erosion. Moreover, no exacerbating inflammation was observed when considering the synovial membranes and the PGE2 and CRP levels. These results seemed to demonstrate that the sustained-release formulation based on GMO could be well-tolerated after intraarticular injection. Moreover, it could have the potential to prevent inflammatory conditions while sustaining drug activity locally over weeks. [less ▲]

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See detailProtective effect of a new CHITOSAN BIOMATERIAL against the development of experimental osteoarthritis lesions in rabbit
Oprenyeszk, Frédéric ULg; Chausson, M; Maquet, V et al

Conference (2013, November 23)

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See detailThe intra-articular injection of alginate-chitosan beads in an hydrogel prevents the development of osteoarthritis in ACLT model
Oprenyeszk, Frédéric ULg; Chausson, M; Maquet, V et al

Conference (2013, September 16)

Purpose To evaluate the effects of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in a viscous thermogelling chitosan-based (H) hydrogel on the development of osteoarthritis (OA) in ... [more ▼]

Purpose To evaluate the effects of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in a viscous thermogelling chitosan-based (H) hydrogel on the development of osteoarthritis (OA) in rabbit. Materials & Methods OA was surgically induced by the transection of the anterior cruciate ligament (ACLT) in rabbits. One week after surgery, animals received a single intra-articular injection (900 µl) of AC beads in H hydrogel (group I), H hydrogel alone (group II) or saline (group III). OA development was followed by X-rays. Blood samples were collected throughout the study to measure biological markers (PGE2 and CRP). Macroscopic observation and histological evaluation of articular cartilage and synovial membrane were performed 6 weeks after surgery. Results The X-rays analysis showed a significant decrease (p <0.05) of the Kellgren and Lawrence score in group I (1.5 ± 0.2) compared with group II (2.2 ± 0.5) and group III (3.0 ± 0.4). The size and the severity of the macroscopic OA cartilage lesion tended to decrease in group I compared to the other groups. The histological global score that refers to all compartments of the knee joint was significantly decreased in group I (11.0 ± 0.7) compared to group II (14.4 ± 0.6, p <0.01) and group III (14.8 ± 0.6, p <0.001). The injection of AC beads in H hydrogel also tended to reduce the synovial membrane inflammation. No significant variation of PGE2 and CRP serum levels were observed in each after 6 weeks follow-up whatever the treatment injected. Conclusion This study showed that AC beads dispersed in H hydrogel prevented OA in ACL transection rabbit model. This effect was not observed with the hydrogel alone, suggesting that AC beads play a role in joint protection. The preventive effect was observed in all joint compartments indicating a global protective effect of this new implantable biomaterial. [less ▲]

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See detailProtective effect of a new biomaterial against the development of experimental osteoarthritis lesions in rabbit: a pilot study evaluating the intra-articular injection of alginate-chitosan beads dispersed in an hydrogel.
Oprenyeszk, Frédéric ULg; Chausson, Mickael; Maquet, Véronique et al

in Osteoarthritis and Cartilage (2013), 21(8), 1099-1107

Objective: This study aimed to evaluate the structural benefit of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in an hydrogel (H) derived from chitosan on the development of ... [more ▼]

Objective: This study aimed to evaluate the structural benefit of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in an hydrogel (H) derived from chitosan on the development of osteoarthritis (OA) in rabbit. Design: OA was induced by the surgical transection of the anterior cruciate ligament in rabbits. Animals received a single intra-articular injection (900 μl) of AC beads in H hydrogel, H hydrogel alone or saline one week after surgery. OA development was followed by X-rays. Blood samples were collected throughout the study to measure biological markers (PGE2 and CRP). Macroscopic observation and histological evaluation of articular cartilage and synovial membrane were performed 6 weeks after surgery. Results: AC beads in H hydrogel prevented from the development of OA based on the reduction of the Kellgren & Lawrence (K&L) score. It also significantly reduced the histological score of cartilage lesion severity. This effect was homogenous on every joint compartment. It was due to a significant effect on cartilage structure and cellularity scores. The injection of AC beads in H hydrogel also tended to reduce the synovial membrane inflammation. No significant variation of biological markers was noted. Conclusions: The present pilot study provides interesting and promising results for the use of AC beads in H hydrogel in animal. It indeed prevented the development of OA cartilage lesions without inflammatory signs. The potencies of this biomaterial to protect OA joint should be further documented. It could then represent a new alternative for viscosupplementation in human OA management. [less ▲]

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See detailThe intra-articular injection of a new chitosan biomaterial prevents the progression of osteoarthritis in ACLT rabbit model
Oprenyeszk, Frédéric ULg; Chausson, Mickael; Maquet, Véronique et al

in Osteoarthritis and Cartilage (2013, April), 21(Supplement April 2013), 69

Purpose To evaluate the effects of a single intra-articular injection of a new biomaterial consisting in a mix of alginate-chitosan (AC) beads and a viscous thermogelling chitosan-based (H) hydrogel on ... [more ▼]

Purpose To evaluate the effects of a single intra-articular injection of a new biomaterial consisting in a mix of alginate-chitosan (AC) beads and a viscous thermogelling chitosan-based (H) hydrogel on cartilage lesion in osteoarthritis (OA) rabbit model. These effects were compared to those obtained with the intra-articular injection of either chitosan-based (H) hydrogel without the AC bead or saline solution. Methods OA was surgically induced by the transection of the anterior cruciate ligament (ACLT) in HYLA albino rabbits. One week after surgery, animals were randomly divided into 3 groups: group I (n=7): mix of AC beads and H hydrogel; group II (n=7): H hydrogel alone; group III (n=7): saline solution (control). The treatments (900 µl) were injected intra-articularly. X-rays from the right knee were performed before surgery, at the time of injection and at sacrifice. The standard radiographs were acquired in extension and scored by the Kellgren and Lawrence (K&L) scale. After 6 weeks, animals were euthanized and the right joint was dissected. The macroscopic evaluation of cartilage from femoral condyles and tibial plateaus stained with India ink was done. Histological sections stained with Safranine-O/fast green from bearing areas of each compartment were evaluated according to the OARSI histological score. Briefly, the evaluation considered: staining of the cartilage matrix (0-6), cartilage structure (0-11), chondrocyte density (0-4) and cluster formation (0-3), where 0 represented a normal situation and 24 points the maximum severity score. Blood samples were collected the day of injection and prior the sacrifice. Prostaglandin E2 (PGE2) and C-reactive protein (CRP) were measured in serum using immunoassays. Results The X-rays analysis showed a significant decrease (p <0.05) of the K&L score in group I (AC beads and H hydrogel; 1.5 ± 0.2) compared with group II (H hydrogel; 2.2 ± 0.5) and group III (saline solution; 3.0 ± 0.4). The size and the severity of the macroscopic OA cartilage lesion tended to decrease in group I compared to the other groups. The histological global score that refers to all compartments of the knee joint was significantly decreased in group I (11.0 ± 0.7) compared to group II (14.4 ± 0.6, p <0.01) and group III (14.8 ± 0.6, p <0.001). No significant variation of PGE2 and CRP serum levels were observed in each after 6 weeks follow-up whatever the treatment injected. Conclusions This study showed that a biphasic hydrogel composed by AC beads and H hydrogel prevented OA in rabbit with ACL transection. This effect was not observed with the hydrogel alone, suggesting that AC beads play a role in joint protection. The preventive effect was observed in all joint compartments indicating a global protective effect of this new viscosupplementation. [less ▲]

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See detailAlginate-chitosan hydrogel beads decrease inflammatory and anabolic mediators produced by human chondrocytes
Oprenyeszk, Frédéric ULg; Sanchez, Christelle ULg; Dubuc, Jean-Emile et al

Poster (2012, September 17)

Introduction Osteoarthritis (OA) is the most prevalent arthritic disease. It is characterized by the degradation of articular cartilage accompanied by the inflammation of the synovial membrane and ... [more ▼]

Introduction Osteoarthritis (OA) is the most prevalent arthritic disease. It is characterized by the degradation of articular cartilage accompanied by the inflammation of the synovial membrane and sclerosis of subchondral bone. OA produces pain and loss of joint function. Today, there is no treatment to cure OA or to delay effectively its progression. Current treatments are mainly based on alleviation of painful symptoms but are unable to restore the cartilage. The development of new scaffold for tissue engineering is a promising approach. Herein, we report the effects of alginate-chitosan hydrogel (AC) beads on the metabolism of chondrocytes. Materials and Methods Human chondrocytes were isolated from OA cartilage and cultured either in AC beads or in alginate (A) beads. AC beads were prepared using chitosan (KiOmedine-CsU ultra-pure chitosan from KitoZyme, Herstal, Belgium) and alginate. The two polymer solutions were prepared separately before being mixed together. Cells were added to the polymer mixture and the cell-containing beads prepared by precipitation in a calcium chloride solution. The chondrocytes embedded in the beads were then cultured in a well defined culture medium for up to 28 days. Cell viability was determined by quantifying the release of lactate deshydrogenase (LDH) in the culture supernatant. Interleukin (IL)-6 and -8, prostaglandin E2 (PGE2), matrix metalloprotease (MMP)-3 and aggrecan were measured by specific ELISA. Finally, nitric oxide (NO) was measured by the Griess reaction. Results Histological analysis of AC beads showed chondrocytes in contact with chitosan trabeculae that were homogeneously distributed in the alginate matrix. LDH level remained below the limit of detection over the culture duration suggesting that AC had no cytotoxic effect. By comparison with culture in A beads, chondrocytes in AC beads produced significantly higher amounts of aggrecan but lowered the levels of MMP-3, NO, IL-6, IL-8 and PGE2. Discussion The contact between cells and AC beads components led us to hypothesize that chitosan has beneficial effects such as anti-inflammatory, anti-catabolic and stimulating effects on cartilage matrix components. Conclusion These particular effects indicate that AC beads are potentially new carriers for cell transplantation, particularly to repair cartilage defects. They could be further developed under various formulations, such as microbeads in combination with hydrogel for efficient viscossuplementation. [less ▲]

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See detailAdvances in biomaterials to repair cartilage
Maquet, Véronique; Chausson, Mickael; Gautier, Sandrine et al

Conference (2012, April 19)

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