Sleep Pattern Interference in the Cognitive Performance of Lusitano Horses.

Like most mammalian, polyphasic sleep, equine sleep can be divided into two phases: the REM (rapid eye movement) phase and the NREM (non-rapid eye movement) phase. For this study, a randomized crossover experiment was conducted using ten purebred Lusitano horses, all dressage athletes aged from three to seven years old. The horses were filmed before the intervention to characterize their sleep patterns. REM sleep deprivation was achieved by not letting the horses attain sternal or lateral recumbency for three consecutive days, totaling 72 h. A spatial memory task and a visual attention test were performed. A recording time of 48 h appeared to be long enough to characterize the sleep patterns of the stalled horses. The total recumbency time of the studied population was lower than that previously reported in horses. Although the recumbency times before and after the intervention were similar, there was a tendency shown by the delta (p = 0.0839) towards an increased time needed to resolve spatial memory tasks in the sleep-deprived group. Future studies may deepen the understanding of horse sleep requirements and patterns, and the effects of environmental changes on horse sleep.

Ultimobranchial body cyst in an adult horse: clinical, histopathologic, and immunohistochemical features.

A 9-y-old Mangalarga Marchador gelding was referred to a veterinary hospital because of a swelling on the upper right side of the neck. Ultrasound examination revealed a multilocular structure adjacent to the thyroid gland with low echogenic content suggestive of fluid. The mass was removed surgically. Histologically, the cystic cavities in the surgical sample were filled with abundant eosinophilic secreta and lined by cuboidal, segmentally ciliated, columnar epithelium with interspersed goblet cells. Segmental crowding of the multilayered lining of the cyst was noted. Immunohistochemistry suggested the presence of both C cells and follicular cells, given the positivity of the immunomarkers calcitonin and TTF-1, respectively. The histogenesis of ultimobranchial cysts is uncertain. Based on clinical, histopathologic, and immunohistochemical identification, the cystic structure in this case is compatible with an ultimobranchial body cyst.

Chondrocyte Homeostasis and Differentiation: Transcriptional Control and Signaling in Healthy and Osteoarthritic Conditions.

Chondrocytes are the main cell type in articular cartilage. They are embedded in an avascular, abundant, and specialized extracellular matrix (ECM). Chondrocytes are responsible for the synthesis and turnover of the ECM, in which the major macromolecular components are collagen, proteoglycans, and non-collagen proteins. The crosstalk between chondrocytes and the ECM plays several relevant roles in the regulation of cell phenotype. Chondrocytes live in an avascular environment in healthy cartilage with a low oxygen supply. Although chondrocytes are adapted to anaerobic conditions, many of their metabolic functions are oxygen-dependent, and most cartilage oxygen is supplied by the synovial fluid. This review focuses on the transcription control and signaling responsible for chondrocyte differentiation, homeostasis, senescence, and cell death and the changes that occur in osteoarthritis. The effects of chondroitin sulfate and other molecules as anti-inflammatory agents are also approached and analyzed.

Chondrogenic potential of mesenchymal stem cells from horses using a magnetic 3D cell culture system.

BACKGROUND: Mesenchymal stem cells (MSCs) represent a promising therapy for the treatment of equine joint diseases, studied due to their possible immunomodulatory characteristics and regenerative capacity. However, the source of most suitable MSCs for producing cartilage for regenerative processes in conjunction with biomaterials for an enhanced function is yet to be established. AIM: To compare the chondrogenicity of MSCs derived from synovial fluid, bone marrow, and adipose tissue of horses, using the aggrecan synthesis. METHODS: MSCs from ten horses were cultured, phenotypic characterization was done with antibodies CD90, CD44 and CD34 and were differentiated into chondrocytes. The 3D cell culture system in which biocompatible nanoparticles consisting of gold, iron oxide, and poly-L-lysine were added to the cells, and they were forced by magnets to form one microspheroid. The microspheroids were exposed to a commercial culture medium for 4 d, 7 d, 14 d, and 21 d. Proteoglycan extraction was performed, and aggrecan was quantified by enzyme-linked immunosorbent assay. Keratan sulfate and aggrecan in the microspheroids were identified and localized by immunofluorescence. RESULTS: All cultured cells showed fibroblast-like appearance, the ability to adhere to the plastic surface, and were positive for CD44 and CD90, thus confirming the characteristics and morphology of MSCs. The soluble protein concentrations were higher in the microspheroids derived from adipose tissue. The aggrecan concentration and the ratio of aggrecan to soluble proteins were higher in microspheroids derived from synovial fluid than in those derived from bone marrow, thereby showing chondrogenic superiority. Microspheroids from all sources expressed aggrecan and keratan sulfate when observed using confocal immunofluorescence microscopy. All sources of MSCs can synthesize aggrecan, however, MSCs from synovial fluid and adipose tissue have demonstrated better biocompatibility in a 3D environment, thus suggesting chondrogenic superiority. CONCLUSION: All sources of MSCs produce hyaline cartilage; however, the use of synovial liquid or adipose tissue should be recommended when it is intended for use with biomaterials or scaffolds.

Nephrosplenic Space Ablation in Horses After Homologous Pericardium Implant Using a Laparoscopic Stapler.

This study aimed to describe and evaluate a laparoscopic technique to promote nephrosplenic space ablation in horses using a homologous pericardium implant, preserved in 98% glycerin and fixed using laparoscopic polydioxanone staples. In this experimental study, six Arabian horses without previous related abdominal diseases were used. The surgical procedures were performed in the standing position under sedation with alpha-2 agonists and opioids, associated with local infiltration of the local anesthetic in the portal sites. The horses were restrained in a stock, and the left flanks were clipped and aseptically prepared. Three portals were created on the left flank, and the homologous pericardium implant, measuring 10 × 5 cm, was introduced into the abdominal cavity covering the nephrosplenic space, positioned between the dorsal border of the spleen and perirenal fascia, fixed with polydioxanone staples using a laparoscopic stapler. Physical examination and blood and peritoneal fluid sample collection were performed on days 0, 1, 3, 7, 14, 30, and 60 of the postoperative period, and an exploratory laparoscopy was performed on day 60 to assess the effectiveness of the technique and eventual complications. There were no difficulties or significant complications during the surgical procedure, and the total average time to perform was 49.83 minutes (±10.19). In the postoperative period, there was a significant increase (P < .05) in the plasma fibrinogen concentration on days 7 and 14 compared with the preoperative moment. The total nucleated cell count in the peritoneal fluid increased (P < .05) on days 1, 3, 7, 14, and 30. After 60 days of the surgical procedure, the physical examination and laboratory data were within the normal range. Exploratory laparoscopy performed on day 60 revealed complete occlusion of the nephrosplenic space, and it was not possible to differentiate the pericardium implant from the scar tissue, not even in the histological evaluation performed on the collected samples. In two horses, omentum adhesion was observed in the region where the implant was fixed, and in two others, a synechia was observed between the implant area and mesocolon without association with clinical complications. The animals were followed up for 36 months at surgery, and no colic signs were observed along this period. It was concluded that the technique of ablation of the nephrosplenic space, using homologous pericardium preserved in 98% glycerin, fixed by polydioxanone staples by laparoscopy, was simple to perform, effective, and free of clinical complications during the period of evaluation, and its use may be indicated as a surgical option in clinical cases of horses with recurrent nephrosplenic entrapment.

Hyaluronic acid has chondroprotective and joint-preserving effects on LPS-induced synovitis in horses.

The intra-articular use of hyaluronic acid (HA) for the treatment of synovitis and osteoarthritis is still controversial. As a consequence, corticosteroids remain the most frequently employed therapeutic agents, despite their potential systemic and local deleterious effects. This study examined the anti-inflammatory, antioxidant, and chondroprotective activities of low and high molecular weight hyaluronic acid (LMW-HA and HMW-HA) on lipopolysaccharide (LPS)-induced synovitis in horses compared to triamcinolone acetonide (TA). LPS was injected in the metacarpophalangeal joints, which were treated intra-articularly with either TA (as control) or LMW-HA or HMW-HA. Joint clinical evaluation and synovial fluid (SF) analysis were performed at 0, 8, 24, and 48 h. The white blood cell counts (WBC), prostaglandin E2 (PGE2), interleukin (IL)-1, IL-6, IL-10, tumor necrosis factor-α, chondroitin sulfate (CS) and HA concentrations, oxidative burst, and HA molecular weights were measured. TA reduced the lameness, swelling, and PGE2 release but increased the SF CS concentrations enormously at 24h and 48h, and decreased the SF HA modal molecular weight. These results indicate the breakdown of articular cartilage aggrecan and SF HA. In contrast, LMW-HA and HMW-HA were less effective in reducing the inflammation symptoms, but preserved the joints because only a modest increase in CS occurred at 24 h, decreasing at 48 h, and the SF HA was maintained. The HA-treatment also had anti-inflammatory actions, and LMW-HA was the most effective in reducing the release of cytokine. In summary, the HA treatment inhibited efficiently the digestion of cartilage proteoglycans and SF HA breakdown.

Does Double Centrifugation Lead to Premature Platelet Aggregation and Decreased TGF-ß1 Concentrations in Equine Platelet-Rich Plasma?

Blood-derived autologous products are frequently used in both human and equine medicine to treat musculoskeletal disorders. These products, especially the platelet-rich plasma (PRP), may contain high concentrations of growth factors (GFs), and thus improve healing in several tissues. Nevertheless, the procedures for preparation of PRP are currently non-standardized. Several protocols, which are based on distinct centrifugation patterns (rotation speed and time), result in PRPs with different characteristics, concerning platelet and GFs concentrations, as well as platelet activation. The aim of the present study was to compare two different protocols for PRP preparation: protocol (A) that is based on a single-centrifugation step; protocol (B), which included two sequential centrifugation steps (double-centrifugation). The results here reported show that the double-centrifugation protocol resulted in higher platelet concentration, while leukocytes were not concentrated by this procedure. Although platelet activation and aggregation were increased in this protocol in comparison to the single-centrifugation one, the TGF-ß1 concentration was also higher. Pearson's correlation coefficients gave a significant, positive correlation between the platelet counts and TGF-ß1 concentration. In conclusion, although the double-centrifugation protocol caused premature platelet aggregation, it seems to be an effective method for preparation of PRP with high platelet and TGF-ß1 concentrations.

Effects of blood-derived products and sodium hyaluronate on equine synovial fluid cells and on synovial fluid from osteochondrotic joints of horses after arthroscopy and administration of treatment.

OBJECTIVE: To compare effects of platelet-rich plasma (PRP), interleukin-1 receptor antagonist protein (IRAP), autologous processed plasma (APP), and sodium hyaluronate treatments on synovial fluid cells in vitro and on synovial fluid obtained from osteochondrotic joints of horses. SAMPLE: Synovial fluid cells from 8 healthy equine tibiotarsal joints (in vitro experiment) and synovial fluid samples from 40 tibiotarsal joints of 25 horses with osteochondrosis dissecans (in vivo experiment). PROCEDURES: Effects of various treatments on concentrations of prostaglandin (PG) E2, interleukin (IL)-1ß, tumor necrosis factor-α, IL-10, and IL-1 receptor antagonist (IL-1ra) were analyzed in cell medium supernatant, and production of reactive oxygen species was analyzed by use of flow cytometry. In an in vivo experiment, synovial fluid samples were collected before and 48 hours after arthroscopy and treatment administration (8 joints/treatment) and evaluated to determine concentrations of hyaluronic acid, chondroitin sulfate, PGE2, tumor necrosis factor-α, IL-1, IL-10, and IL-1ra. RESULTS: All in vitro treatments reduced reactive oxygen species production, PRP increased PGE2 concentrations, and PRP, IRAP, and APP increased IL-1ra concentrations. Only IRAP and APP increased IL-1 concentrations. For the in vivo experiment, PRP increased and IRAP decreased PGE2 concentrations in synovial fluid after arthroscopy. All treatments increased IL-1ra concentrations, but only sodium hyaluronate resulted in a significant increase in concentration, compared with the concentration for untreated joints. Also, IRAP reduced hyaluronic acid breakdown in synovial fluid. CONCLUSIONS AND CLINICAL RELEVANCE: PRP should be used with caution in the period immediately after arthroscopy and treatment of osteochondrotic joints of horses. All treatments had antioxidant effects. Sodium hyaluronate, APP, and IRAP might help ameliorate joint inflammation.

Physiotherapy protocol during initial postoperative period of arthroscopy in horses / Protocolo fisioterápico durante o período pós-operatório inicial de cirurgia artroscópica em equinos

This study evaluated the effects of a physiotherapy protocol applied in joints with osteochondritis dissecans submitted to arthroscopy. Twelve horses totaling twenty joints were used and divided into two uniform groups, according to articular lesion grade. Treated Group (TG) received the physiotherapy protocol (cryotherapy, passive rage motion and controlled exercise) that initiate just after anesthetic recovery and extended for five days. Control Group (CG) remained resting in stall during the same period. Physical examination and synovial fluid analysis were used to evaluate the treatment. The synovial fluid examination consisted of physical analysis (color, aspect, and viscosity), mucin clot evaluation, Serum Amyloid A, Prostaglandin E2 and urea concentration. Synovial samples were collected by arthrocentesis at the beginning of the surgical procedure (D1), 48 hours (D3) and 96 hours (D5) after surgery. Before arthroscopy and daily during the postoperative period joints were evaluated by physical exam: superficial temperature (°C), range of motion (degrees) and circumference (centimeters). The joint physical examination showed no significant difference between groups and neither along the days for the same group. The parameters of synovial fluid showed difference over the moments in each group but didn't have difference between groups. Color and aspect had the same patterns across moments, in CG fluid had significant change when compared D1 with D3 (color and aspect: p<0.001) and D5 (color: p<0.001; aspect: p<0.05) becoming mostly bloody and cloudy in D3 and D5. However in TG the difference was significant just between D1 and D3 (color and aspect: p<0.05), showing an improvement of synovial fluid in D5 (color and aspect: p<0.05). Viscosity and mucin clot evaluation showed significant change in CG between D1 and D3 (viscosity: p<0.01; mucin clot: p<0.05) and between D1 and D5 (viscosity: p<0.01;mucin clot: p<0.01). In TG no significant difference of viscosity and mucin clot was observed over the moments, showing an early improvement of synovial fluid quality. The Serum Amyloid A concentration showed an extremely significant increase in CG (p<0.001) when compared D1 (1217.13±664.47µg/mL) and D3 (42423.80±52309.31µg/mL). The comparison between D1 and D5 in CG, and across moments in TG, had no statistical difference. The PGE2 eicosanoid remained statistically unchanged all over the time. Urea showed significant increase in D3 when compared to D1 (p<0.001) in CG, and had no variation in TG. The physiotherapy protocol minimized the inflammatory mediators and provided minor alterations in synovial fluid after arthroscopy.(AU)

Este estudo avaliou os efeitos de um protocolo fisioterápico, aplicado em articulações com osteocondrite dissecante, submetidas à artroscopia. Foram utilizados 12 cavalos, totalizando 20 articulações, divididas em dois grupos homogêneos de acordo com a graduação da lesão articular. O grupo tratado (GT) recebeu o protocolo fisioterápico (crioterapia, movimentação passiva e exercício controlado) que se iniciou imediatamente após a recuperação anestésica e se estendeu por cinco dias. O grupo controle (GC) permaneceu em repouso na baia, pelo mesmo período. Exame físico da articulação e análise do líquido sinovial foram utilizados para avaliar o tratamento. O exame do líquido sinovial consistiu em análise física (cor, aspecto e viscosidade), avaliação do coágulo de mucina e concentrações de amiloide sérica A, prostaglandina E2 e ureia. Amostras de líquido sinovial foram colhidas por artrocentese no início do procedimento cirúrgico (D1) e após 48 (D3) e 96 horas (D5) do procedimento cirúrgico. Antes da artroscopia e diariamente no período pós-operatório, as articulações foram avaliadas por exame físico: temperatura superficial (°C), ângulo de flexão (graus), circunferência (centímetros). A avaliação física das articulações não apresentou diferença significativa entre os grupos nem ao longo dos dias em cada grupo. Nas análises do líquido sinovial, observou-se uma variação diferente entre os momentos em cada grupo porém sem diferença significativa entre os grupos. A cor e o aspecto tiveram resultados semelhantes ao longo do tempo, no GC houve uma alteração significativa quando comparados D1 e D3 (cor e aspecto: p<0,001) e D1 e D5 (cor: p<0,001; aspecto: p<0,05) tornando-se sanguinolento e turvo na maioria das amostras em D3 e D5. Já no GT, houve diferença significativa apenas entre D1 e D3 (cor e aspecto: p<0,05), demonstrando melhora no líquido sinovial em D5 (cor e aspecto: p<0,05). A viscosidade e o coágulo de mucina apresentou alteração significativa no GC entre D1 e D3 (viscosidade: p<0,01; coágulo de mucina: p<0,05) e entre D1 e D5 (viscosidade e coágulo de mucina: P<0,01). No grupo tratado não foram observadas alterações significativas em viscosidade e coágulo de mucina, ao longo dos momentos, demonstrando uma melhora precoce na qualidade do líquido sinovial. A amiloide sérica A apresentou um aumento extremamente significante no GC (p<0,001) quando comparados D1 (1217,13±664,47µg/dL) e D3 (42423,80±52309,31µg/dL). Quando comparados D1 e D5 no GC e ao longo do tempo no GT não foram observadas diferenças significativas. A concentração de PGE2 permaneceu sem alterações. As mensurações de ureia apresentaram aumento significativo em D3 quando comparado a D1 (p<0,001) no GC e não apresentou variação no GT. O protocolo fisioterápico minimizou os mediadores inflamatórios e proporcionou menor alteração do líquido sinovial após artroscopia.(AU)

Short- and long-term effects of platelet-rich plasma upon healthy equine joints: Clinical and laboratory aspects.

This study aimed to verify whether transient inflammatory reactions incited by the administration of intra-articular platelet-rich plasma (PRP) affected joint components through short- and long-term in vivo evaluation of inflammatory biomarkers and extracellular matrix degradation products in synovial fluid. The effects of PRP were analyzed in a short phase protocol (SPP) and in a prolonged phase protocol (PPP), using saline-injected joints as controls. In the SPP, higher white blood cell counts and prostaglandin E2 and total protein concentrations were observed in the synovial fluid of PRP-treated joints (P < 0.05). There were no differences between the interleukin-1ß, interleukin-1 receptor antagonist protein, tumor necrosis factor-α, chondroitin sulfate, or hyaluronic acid concentrations between PRP and saline injected joints. In the PPP, there were no differences in evaluated parameters between groups. PRP injection elicits a mild and self-limiting inflammatory response shortly after administration, without long-term deleterious effects on joint homeostasis.

Effets à court et à long terme de le plasma riche en plaquettes sur les articulations sains chez les équines : aspects cliniques et laboratoiren. Cette étude a pour but de vérifier si les réactions inflammatoires passagères induites par l'administration intra articulaire de Plasma Enrichi en Plaquettes (PRP) affectent les composants articulaires. Les bio-marqueurs de l'inflammation et les produits de dégradation de la matrice extracellulaire ont été évalués in vivo, dans le liquide synovial, à court et long terme. Les effets du PRP ont été analysés lors d'un protocole court terme et lors d'un protocole long terme et les articulations contrôles ont été injectées avec du liquide physiologique. Le protocole court terme a révélé des comptages de globules blancs et de prostaglandine E2, ainsi que des concentrations en protéines totales plus élevés dans le liquide synovial des articulations traitées au PRP (P < 0,05). Cependant, aucune différence de concentration en interleukine-1 bêta, en protéine antagoniste des récepteurs à l'interleukine-1, en facteur de nécrose tumorale alpha, en chondroïtine sulfate et en acide hyaluronique n'a été notée entre les articulations injectées au PRP et les articulations contrôles. Le protocole long terme n'a démontré aucune différence des paramètres évalués entre les deux groupes. L'injection de PRP provoque une réponse inflammatoire légère et auto-limitante rapidement après l'administration, sans effet délétère sur l'homéostasie de l'articulation à long terme.(Traduit par les auteurs).

Platelet-rich plasma in orthopedic therapy: a comparative systematic review of clinical and experimental data in equine and human musculoskeletal lesions.

BACKGROUND: This systematic review aimed to present and critically appraise the available information on the efficacy of platelet rich plasma (PRP) in equine and human orthopedic therapeutics and to verify the influence of study design and methodology on the assumption of PRP's efficacy. We searched Medline, PubMed, Embase, Bireme and Google Scholar without restrictions until July 2013. Randomized trials, human cohort clinical studies or case series with a control group on the use of PRP in tendons, ligaments or articular lesions were included. Equine clinical studies on the same topics were included independently of their design. Experimental studies relevant to the clarification of PRP's effects and mechanisms of action in tissues of interest, conducted in any animal species, were selected. RESULTS: This review included 123 studies. PRP's beneficial effects were observed in 46.7% of the clinical studies, while the absence of positive effects was observed in 43.3%. Among experimental studies, 73% yielded positive results, and 7.9% yielded negative results. The most frequent flaws in the clinical trials' designs were the lack of a true placebo group, poor product characterization, insufficient blinding, small sampling, short follow-up periods, and adoption of poor outcome measures. The methods employed for PRP preparation and administration and the selected outcome measures varied greatly. Poor study design was a common feature of equine clinical trials. From studies in which PRP had beneficial effects, 67.8% had an overall high risk of bias. From the studies in which PRP failed to exhibit beneficial effects, 67.8% had an overall low risk of bias. CONCLUSIONS: Most experimental studies revealed positive effects of PRP. Although the majority of equine clinical studies yielded positive results, the human clinical trials' results failed to corroborate these findings. In both species, beneficial results were more frequently observed in studies with a high risk of bias. The use of PRP in musculoskeletal lesions, although safe and promising, has still not shown strong evidence in clinical scenarios.

Autologous processed plasma: cytokine profile and effects upon injection into healthy equine joints.

This experimental controlled study was performed to evaluate the composition of autologous processed plasma (APP), and the effects of APP intra-articular injection into healthy equine metacarpophalangeal joints. The effects on joints were analysed with a short-phase protocol and a prolonged-phase protocol using saline-injected joints as controls. For the short protocol, horses received one intra-articular APP injection. Synovial fluid samples were collected prior to the injection and 3, 6, 24, 48, and 16 h after treatment. For the prolonged protocol, the joints received three weekly injections of APP, and samples were collected at 0, 7, 14, 21, and 28 days before APP administration. IL1-ra level was found to be increased in APP compared to plasma. Upon intra-articular administration of APP, transient (up to 24 h) increases in white blood cell (WBC) counts along with elevated protein and prostaglandin E2 (PGE2) concentrations were observed in the treated joints. Over the 28-day observation period, APP did not elicit changes relative to baseline levels, but WBC counts, PGE2 and chondroitin sulphate concentrations were lower than those found in the control. In conclusion, APP intra-articular injection induced a mild and transitory inflammatory response but no inflammation reaction was observed over a longer period of treatment and observation.

Evaluation of chitosan-GP hydrogel biocompatibility in osteochondral defects: an experimental approach.

BACKGROUND: Articular cartilage, because of its avascular nature, has little capacity for spontaneous healing, and tissue engineering approaches, employing different biomaterials and cells, are under development. Among the investigated biomaterials are the chitosan-based hydrogels. Although thoroughly studied in other mammalian species, studies are scarce in equines. So, the aim of the present study was to investigate the biocompatibility of chitosan-GP in horse joints submitted to high mechanical loads. RESULTS: An osteochondral defect was created by arthroscopy in the medial surface of lateral trochlea of talus of left or right leg, randomly selected, from six healthy geldings. The defect was filled up with chitosan-GP. The contralateral joint received an identical defect with no implant. The chondral fragment removed to produce the defect was collected, processed and used as the "Initial" sample (normal cartilage) for histology, immunohistochemistry, and metabolic labelling of PGs. After 180 days, the repair tissues were collected, and also analyzed. At the end of the experiment (180 days after lesion), the total number of cells per field in repair tissues was equal to control, and macrophages and polymorphonuclear cells were not detected, suggesting that no significant inflammation was present. These cells were able to synthesize type II collagen and proteoglycans (PGs). Nevertheless, the cell population in these tissues, both in presence of chitosan-GP and in untreated controls, were heterogeneous, with a lower proportion of type II collagen-positives cells and some with a fibroblastic aspect. Moreover, the PGs synthesized in repair tissues formed in presence or absence of chitosan-GP were similar to those of normal cartilage. However, the chitosan-GP treated tissue had an disorganized appearance, and blood vessels were present. CONCLUSIONS: Implanted chitosan-GP did not evoke an important inflammatory reaction, and permitted cell growth. These cells were able to synthesize type II collagen and PGs similar to those synthesized in normal cartilage and in healing tissue without implant, indicating its chondrocyte nature.

Relevance of synovial fluid chondroitin sulphate as a biomarker to monitor polo pony joints.

Osteoarthritis (OA) of the metacarpophalangeal joint is the most common articular disease in polo ponies leading to early retirement. A biomarker that would discriminate between pathological and physiological changes secondary to exercise could be helpful in OA prevention. The aim of this study was to investigate the effects of polo training on synovial fluid biomarkers of inflammation and cartilage turnover in polo ponies of different skill levels. Synovial fluid samples were collected from metacarpophalangeal joints of polo ponies before and during the polo season (320 d). Nucleated cells, soluble protein, prostaglandin E2 (PGE2), glycosaminoglycans (GAG), and urea were measured. The main synovial fluid GAG are chondroitin sulphate (CS, ~25 µg/mL) and hyaluronic acid (HA, ~400 µg/mL). After a polo match, a transitory increase in protein and PGE2, but not CS and HA, occurred (expressed as urea ratio), returning to basal levels in 24 h. During the polo season, the number of synovial fluid nucleated cells was always in the normal range. Increases in protein and HA occurred during the initial 40 to 80 d, returning to basal levels afterwards. In contrast, in polo prospects the concentration of CS steadily increased during the season. Long-term follow-up revealed that the synovial fluid CS was significantly higher in polo ponies that developed joint diseases within 24 months following our study. In conclusion, CS seems to be an early marker of articular cartilage damage.

L'arthrose (OA) de l'articulation métacarpophalangienne est la maladie articulaire la plus fréquente chez les poneys de polo menant à la retraite anticipée. Un biomarqueur qui était discriminateur entre les changements pathologiques et physiologiques secondaires au exercice pourrait être utile pour la prévention de l'OA. L'objectif de la présente étude était examiner les effets de l'activité de polo sur les biomarqueurs de l'inflammation et de le métabolisme de la cartilage dans le liquide synovial des poneys de polo de différents niveaux de qualification. Le SF était obtenu à partir de les articulations métacarpophalangiennes de poneys de polo, avant et pendant la saison de polo (320 jours). Les cellules nucléés, protéine soluble, prostaglandine E2 (PGE2), glycosaminoglycanes (GAG) et l'urée ont été mesurés. Les principaux GAG de le liquide synovial sont le chondroïtine sulfate (CS, ~25 µg/mL) et l'acide hyaluronique (HA, ~400 µg/mL). Après un match de polo, ocorru une augmentation transitoire de la protéine et de la PGE2, mais pas de CS et de HA (exprimé comme le raison d'urée), qui a retourné aux niveaux basal dans 24 h. Pendant la saison de polo, le numero de cellules nucléés dans le liquide synovial était toujours normaux. La protéine et le HA augmentaient pendant les premiers 40­80 jours, mais tous les deux sont retournés aux niveaux de base plus tard. En contraste, dans le group de jeunes poneys (G1), la concentration de CS a augmenté régulièrement pendant la saison. Accompagnant à long terme avait révéle que le CS de liquide synovial était significativement plus élevée chez les poneys de polo que, dans les 24 mois suivants, avaient developpé des maladies articulaires. En conclusion, le CS du liquide synovial semble être un marqueur précoce des destructions de la cartilage articulaire.(Traduit par les auteurs).

Lipopolysaccharide-induced inhibition of transcription of tlr4 in vitro is reversed by dexamethasone and correlates with presence of conserved NFκB binding sites.

Engagement of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) is a master trigger of the deleterious effects of septic shock. Horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. Analysis of tlr4 promoters revealed high similarity among LPS-sensitive species (human, chimpanzee, and horse) and low similarity with LPS-resistant species (mouse and rat). Four conserved nuclear factor kappa B (NFκB) binding sites were found in the tlr4 promoter and two in the md2 promoter sequences that are likely to be targets for dexamethasone regulation. In vitro treatment of equine peripheral blood mononuclear cells (eqPBMC) with LPS decreased transcripts of tlr4 and increased transcription of md2 (myeloid differentiation factor 2) and cd14 (cluster of differentiation 14). Treatment with dexamethasone rescued transcription of tlr4 after LPS inhibition. LPS-induced transcription of md2 was inhibited in the presence of dexamethasone. Dexamethasone alone did not affect transcription of tlr4 and md2.

Do blood components affect the production of reactive oxygen species (ROS) by equine synovial cells in vitro? / Os componentes do sangue afetam a produção de (ERO) pelas células sinoviais de equinos in vitro?

Blood-derived products are commonly administered to horses and humans to treat many musculoskeletal diseases, due to their potential antioxidant and anti-inflammatory effects. Nevertheless, antioxidant effects have never been shown upon horse synovial fluid cells in vitro. If proved, this could give a new perspective to justify the clinical application of blood-derived products. The aim of the present study was to investigate the antioxidant effects of two blood-derived products - plasma (unconditioned blood product - UBP) and a commercial blood preparation (conditioned blood product - CBP)¹ - upon stimulated equine synovial fluid cells. Healthy tarsocrural joints (60) were tapped to obtain synovial fluid cells; these cells were pooled, processed, stimulated with lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA), and evaluated by flow cytometry for the production of reactive oxygen species (ROS). Upon addition of any blood-derived product here used - UBP and CBP - there was a significant decrease in the oxidative burst of synovial fluid cells (P<0.05). There was no difference between UBP and CBP effects. In conclusion, treatment of stimulated equine synovial cells with either UBP or CBP efficiently restored their redox equilibrium.

Produtos derivados do sangue são comumente usados, tanto no homem como em cavalos, para tratar diversas doenças musculoesqueléticas, principalmente devido a seus efeitos antioxidantes e anti-inflamatórios. Contudo, efeitos antioxidantes nunca foram demonstrados em células de líquido sinovial in vitro. Caso esses efeitos sejam efetivamente demonstrados, uma nova perspectiva para justificar a aplicação clínica desses produtos poderia surgir. Sendo assim, o objetivo do presente estudo foi investigar os efeitos antioxidantes de dois produtos derivados de sangue - plasma (produto de sangue não condicionado - UBP) e uma preparação comercial de sangue (produto de sangue condicionado - CBP)¹ - sobre células estimuladas extraídas do líquido sinovial de equinos. Articulações tibiotársicas saudáveis (60) foram puncionadas para a obtenção de células de líquido sinovial; essas células foram concentradas, processadas, estimuladas com lipopolissacarídeos (LPS) ou forbol 12-miristato 13-acetato (PMA), e avaliadas por citometria de fluxo quanto à produção de espécies reativas de oxigênio (ROS). Após a adição de ambos os produtos derivados do sangue - UBP ou CBP - ocorreu uma significativa queda no burst oxidativo em células do líquido sinovial (P<0,05). Não houve diferença entre os efeitos de UBP e CBP. Em conclusão, tratamento de células estimuladas do líquido sinovial de equinos com UBP ou CBP restaurou eficientemente o equilíbrio redox das células.

Urinary glycosaminoglycans in horse osteoarthritis. Effects of chondroitin sulfate and glucosamine.

Our objectives were to characterize the urinary excretion of glycosaminoglycans (GAGs) in horse osteoarthritis, and to investigate the effects of chondroitin sulfate (CS) and glucosamine (GlcN) upon the disease. Urinary GAGs were measured in 47 athletic horses, 20 healthy and 27 with osteoarthritis. The effects of CS and GlcN were investigated in mild osteoarthritis. In comparison to normal, urinary GAGs were increased in osteoarthritis, including mild osteoarthritis affecting only one joint. Treatment with CS+GlcN led to a long lasting increase in the urinary CS and keratan sulfate (KS), and significant improvement in flexion test of tarsocrural and metacarpophalangeal joints was observed. In conclusion, urinary CS and KS seems to reflect the turnover rates of cartilage matrix proteoglycans, and the measurement of these compounds could provide objective means of evaluating and monitoring joint diseases.

Identificação dos níveis séricos do fator de crescimento tipo insulina 1 em potros com osteocondrose / Identification of insulin-like growth factor-I serum levels in foals with osteo-chondrosis

A osteocondrose é uma das doenças ortopédicas do desenvolvimento mais comuns em cavalos, e deve ser encarada como uma desordem multifatorial. Caracteriza-se por ser uma doença dinâmica, onde o processo de reparo inicia-se quase que imediatamente após a formação da lesão osteocondral. A intensidade e eficácia deste reparo são fortemente relacionados à idade, e estão associados a reposição dos componentes da matriz cartilagínea. Uma vez que o fator de crescimento tipo insulina-1 (IGF-1) age regulando o crescimento da cartilagem articular, este estudo objetivou descrever os níveis séricos de IGF-I, insulina e glicose em potros Puro Sangue Lusitano hígidos ou com osteocondrose, desde o nascimento até 18 meses de idade. Dos potros acompanhados, 76,08 por cento apresentaram sinais radiográficos de osteocondrose com um mês de idade, porém somente 16,2 por cento mantiveram as lesões aos 18 meses. As concentrações de IGF-1 alcançaram picos entre 14 e 16 meses, equivalente ao início da puberdade. As concentrações de IGF-1 nos potros com osteocondrose foram menores que potros sadios, aos 2 e 5 meses (P<0,05), e os de insulina aos 2 meses (P<0,05). Em criatórios com alta ocorrência de osteocondrose recomenda-se que as mensurações dos níveis séricos de IGF-1 e insulina ocorram durante os primeiros 6 meses de idade, para que haja tempo hábil de se estabelecer medidas profiláticas e de tratamento.

Osteochondrosis is the most common orthopaedic developmental disorder in horses and has been traditionally defined as a multifactorial disease. The disease had a very dynamic character in which the repair process starts almost immediately after the lesion has formed. The intensity and efficacy of this repair process is strongly age-related and is determined by the turnover rate of the components of the extracellular matrix of the articular cartilage. Since the insulin-like growth factor-I (IGF-1) acts regulating the growth of articular cartilage, this study aimed to describe the serum levels of IGF-1, insulin and glucose in healthy Lusitano foals and foals with osteochondrosis, from birth to 18 months of age. At one month 76.08 percent of the foals showed radiographic signs of osteochondrosis, but at age of 18 months the percentage dropped to 16.2 percent. The IGF-1 concentrations reached peak values at age of 14 to 16 months, equivalent to the onset of puberty. The IGF-1 concentrations in foals with osteochondrosis were lower than in healthy 2 to 5-month-old foals (P<0.05), and the insulin at age of 2 months (P<0.05). On farms with high incidence of osteocondrosis is recommended that measurement of serum IGF-1 and insulin occur during the first 6 months of age, to have enough time to establish preventive and therapeutic measures.

Bilateral sinus cysts in a filly treated by endoscopic sinus surgery.

Bilateral cysts in the frontal and caudal maxillary sinuses in a filly treated by endoscopic sinus surgery (sinoscopy) and triangulation technique are described. Sinoscopy has the advantage of being a minimally invasive technique and permits a complete inspection of the frontal and maxillary sinuses, which is not possible through flap sinusotomy.