Glycosaminoglycans (GAGs) are long unbranched polysaccharides consisting of repeating disaccharide units that are found in various tissues and fluids in horses. They are integral components of connective tissues, contributing to the structural integrity and function of cartilage, tendons, and synovial fluid. GAGs are involved in maintaining joint health and facilitating smooth movement by providing lubrication and shock absorption. Common types of glycosaminoglycans in horses include chondroitin sulfate, dermatan sulfate, and hyaluronic acid. Changes in GAG levels and composition can be indicative of joint disorders or degenerative conditions in horses. This page compiles peer-reviewed research studies and scholarly articles that explore the biochemical properties, physiological roles, and clinical implications of glycosaminoglycans in equine health.
Oikawa M, Katayama Y, Yoshihara T, Kaneko M, Yoshikawa T.The morphology of the arteries in the uterine wall was studied in three multiparous aged mares that had suffered repeated pregnancy failure. The uterine wall arteries exhibited elastosis of the intima or adventitia, or both, resembling "physiological pregnancy sclerosis". In areas affected by elastosis, degeneration of the pre-existing elastic fibres and increased glycosaminoglycans were frequently observed. Newly formed elastic fibres were not evident. Delayed resorption due to disordered metabolic turnover of the elastin was thought to be an important factor in the pathogenesis of the arteri...
Richardson DW, Clark CC.Hexosamine concentration (an index of proteoglycan content), DNA content (an index of cellularity), and [35S]sulfate incorporation (an index of proteoglycan synthesis) of articular cartilage were measured in biopsy specimens from medial proximal sesamoid bone, medial condyle of the third metacarpal bone, and proximal dorsal rim of the proximal phalanx in both metacarpophalangeal joints of 6 adult horses. One limb was then placed in a fiberglass cast that extended down from the proximal portion of the metacarpus and enclosed the hoof; the other limb was not casted. After 30 days of stall confin...
MacDonald MH, Stover SM, Willits NH, Benton HP.Explant cultures were set up, using articular cartilage obtained from metatarsophalangeal joints of 11 horses. Explants from 2 horses were used to determine culture conditions appropriate for tissue viability. The cartilage explants maintained steady-state metabolism of proteoglycans during a 13-day evaluation period. The metabolic response of equine articular cartilage to incubation with recombinant human interleukin 1 (0.01 to 100 ng/ml) was studied, using cartilage obtained from the remaining 9 horses, age of which ranged from 3 months to 20 years. Interleukin 1 induced a dose-dependent rel...
Lapointe JM, Laverty S, Lavoie JP.Case histories, results of synovial fluid analyses, treatment regimens and outcome are described for 15 adult Standardbred horses with confirmed post-injection septic arthritis. Joint sepsis followed injection of corticosteroids, hyaluronic acid, polysulphated glycosaminoglycan, or local anaesthetic. The median interval from injection to appearance of clinical signs was 2.5 days, and median interval from injection to referral was 9 days. The median initial synovial leucocyte count on admission was 57 x 10(9)/litre, but there was a wide range of values (18-258 x 10(9)/litre). The median synovia...
Vachon AM, McIlwraith CW, Powers BE, McFadden PR, Amiel D.Using biodegradable pins, sternal cartilage autografts were fixed into osteochondral defects of the distal radial carpal bone in ten 2 to 3-year-old horses. The defects measured 1 cm2 at the surface and were 4 mm deep. Control osteochondral defects of contralateral carpi were not grafted. After confinement for 7 weeks, horses were walked 1 hour daily on a walker for an additional 9 weeks. Horses were euthanatized at 16 weeks. Half of the repair tissue was processed for histologic and histochemical (H&E and safranin-O fast green) examinations. The other half was used for the following bioch...
Oikawa M, Kaneko M, Yoshikawa T.To elucidate the pathomorphogenesis of extremely shortened small-intestinal villi, occurring spontaneously in neonatal foals, the morphology of the small intestine with stunted villi was studied in eight cases. All intestinal wall elements and the villi were poorly developed. Most villi were found to be extremely short throughout the entire length of the small intestine. The villous core consisted of undifferentiated, fibroblast-like cells held loosely together by ground substance which was rich in glycosaminoglycan. Development of the villous lamina propria was poor with respect to capillarie...
Brusie RW, Sullins KE, White NA, Coffin PC, Parker GA, Anver MR, Rosenberger JL.This study was conducted to determine the efficacy of sodium hyaluronate (SH) with antibiotic therapy and joint lavage for reducing acute inflammatory and degenerative changes induced by septic arthritis. Septic arthritis was induced in six adult horses by inoculating the tarsocrural joints with 1 x 10(4) colony-forming units of Staphylococcus aureus. When clinical signs appeared, trimethoprim-sulphamethoxazole (30 mg/kg bodyweight [bwt] daily) and phenylbutazone (4.4 mg/kg bwt sid) were administered and continued until termination of the study (Treatment Day 18). Twenty-four hours post inocul...
Saari H, Tulamo RM, Konttinen YT, Sorsa T.A high performance liquid chromatography (HPLC) procedure suitable for the simultaneous determination of the molecular size and concentration of macromolecular hyaluronate and proteoglycans in synovial fluid has been developed. Irrigation of the equine tarsocrural joint with 20 ml physiological saline (PSS) caused a mild inflammation with an increase of proteoglycans in the synovial fluid over the baseline arthrocentesis control sample. Proteoglycan and hyaluronate in the synovial fluid did not interact to form hyaluronate-proteoglycan aggregates, but separated as distinct chromatographic peak...
Rashmir-Raven AM, Coyne CP, Fenwick BW, Gaughan EM, Andrews GA, DeBowes RM.The ability of polysulfated glycosaminoglycans (PSGAG) to inhibit the complement cascade was evaluated. The role of complement in inflammation and infection has been well documented. Inhibition of the complement cascade by PSGAG could explain why intra-articularly administered PSGAG diminish diarthrodial joint inflammation and potentiate septic arthritis in horses. Hemolytic complement testing was performed to evaluate the effect of PSGAG on the equine classical and alternate pathways of complement, using rabbit erythrocytes as the target cells. Concentration of PSGAG between 0.2 mg/ml and 0.6...
Caron JP, Eberhart SW, Nachreiner R.Articular cartilage explants from 3 horses were maintained in tissue culture to test the effects of a polysulfated glycosaminoglycan on proteoglycan biosynthesis. Cultures were exposed to concentrations of 0, 50, or 200 micrograms of the drug/ml for either 2 days or 6 days, and labeled with 35S, before measuring the content of sulfated proteoglycan in the culture media and in extracts of cartilage. In a second experiment, the explants were incubated with the isotope and subsequently exposed to the same concentrations of the polysulfated glycosaminoglycan for 4 days. Subsequently, the amount of...
Nixon AJ, Krook LP, Roth JE, King JM.A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. After euthanasia at week 8, the treated and control joints were examined for gross changes, and samples of cartilage and subchondral bone, synovial membrane, and peripheral lymph nodes were examined histologically. Depletion of cartilage ma...
Miksík I, Deyl Z.Skin and aorta collagen specimens of Wistar rats, white mice, beagle dogs, cats, horses, and human necropsies of different ages were examined with respect to the content of glycated products. The data presented show that (a) glycation and accumulation of the chromophore(s) are comparable in collagen samples from different species of comparable age; (b) glycation and pigmented accumulation increase markedly during the first 5-10 years of age; (c) the extent of glycation is different in different tissues (in particular, glycation of aortal collagen is about twice that of skin collagen); and (d) ...
Dyson SJ.This paper describes the clinical and radiographic features, and response to treatment, of 45 horses which showed lameness that was improved by intra-articular anaesthesia of the distal interphalangeal (DIP) joint. Although many horses had poor conformation of the foot of the lame limb, the majority showed no localising clinical signs suggestive of involvement of the DIP joint. Lameness was usually unilateral. No horse with bilateral lameness responded to treatment. Palmar digital nerve blocks frequently improved or alleviated lameness, although in some horses palmar (abaxial sesamoid) nerve b...
Vachon AM, McIlwraith CW, Keeley FW.Periosteal autografts were used for repair of large osteochondral defects in 10 horses aged 2 to 3 years old. In each horse, osteochondral defects measuring 1.0 x 1.0 cm2 were induced bilaterally on the distal articular surface of each radial carpal bone. Control and experimental defects were drilled. Periosteum was harvested from the proximal portion of the tibia and was glued into the principal defects, using a fibrin adhesive. Control defects were glued, but were not grafted. Sixteen weeks after the grafting procedure, the quality of the repair tissue of control and grafted defects was asse...
Ferlazzo AM, Vinci R, Panzera M, Ferlazzo A, Calatroni A.1. The measured values of acid glycosaminoglycan (GAG) concentration in plasma or in serum show significant differences between trained and untrained horses and among sedentary horses and other animal species (cattle, rabbit, sheep). 2. Diurnal variations in serum GAG levels are reported (cattle), and changes in plasma GAG concentrations after road transport (horses) and in late pregnancy (mares, cows), while sex, age and breed do not affect them.
Alwan WH, Carter SD, Bennett D, Edwards GB.Horse articular cartilage glycosaminoglycans (GAGs) were measured in synovial fluids from 48 joints affected with osteoarthritis (OA), 22 normal joints, four joints with osteochondritis, three joints with traumatic arthritis and seven joints infected with bacteria. Serum and urine from individual horses were also examined for the presence of GAGs. High levels of GAGs were found in synovial fluids (SF) from horses with OA. In each case, the level was higher in the synovial fluid than in the serum or urine from the same horse. Horses with OA showed high GAG levels in SF, serum and urine compared...
Varner DD, Forrest DW, Fuentes F, Taylor TS, Hooper RN, Brinsko SP, Blanchard TL.Eighteen fertile mares were used to determine the effects of the oestrous cycle and location in the reproductive tract on the amount and concentration of glycosaminoglycans in luminal fluids. Ovariohysterectomies were performed in 3 groups of 6 mares on Day 3 of behavioural oestrus, within 6 h after ovulation or on Day 8 of dioestrus. The lumina of the uterine horns and oviducts ipsilateral and contralateral to the active ovary were flushed and fluid was aspirated from the dominant follicle in the oestrous preovulation group. Glycosaminoglycans and protein concentrations were measured in these...
Vachon AM, Keeley FW, McIlwraith CW, Chapman P.Articular cartilage specimens from the distal articular surface of 32 radiocarpal bones from 24 2- to 5-year-old horses were analyzed. The total collagen content was determined on the basis of the 4-hydroxyproline content, using a colorimetric method. A method for estimating the proportions of types-I and -II collagen by measuring spectrophotometric densities of specific cyanogen bromide peptide bands from mixtures of types-I and -II collagen on sodium dodecyl sulfate-polyacrylamide gels was used. The cyanogen bromide peptides representative of each collagen types-I and -II were identified. Th...
Little CB, Hilbert BJ, Wickstrom S, Hedlund BE.An alcian blue precipitation method for quantifying the hyaluronic acid (HA) and sulphated glycosaminoglycan concentration (SGAG) in solutions containing both compounds was assessed. The assay was found to be rapid and reliable in solutions containing 0 to 200 mg of HA/dl and 50 to 1,000 micrograms of SGAG/dl, and was not affected by the presence of protein, hemoglobin, or methemoglobin in concentrations normally found in synovial fluid. The HA and SGAG concentrations in intercarpal synovial fluid from 13 clinically normal and 11 arthritic horses were evaluated. A relationship was not found be...
Alwan WH, Carter SD, Bennett D, May SA, Edwards GB.Degradation of cartilage in osteoarthritis of man results in the release of sulphated glycosaminoglycans, particularly keratan sulphate, into tissue fluids. A study was made to evaluate these markers for osteoarthritis in the horse. Synovial fluid and serum levels of keratan sulphate, measured by an ELISA-inhibition technique, and sulphated glycosaminoglycans measured by specific dye binding assay, were found to be significantly increased (P less than 0.001) in joints from horses with osteoarthritis, compared with normal joints. Synovial fluids from joints with infective arthritis also showed ...
Glade MJ.Low molecular weight polysulfated glycosaminoglycan (PSGAG) stimulated net collagen and glycosaminoglycan synthesis by normal and arthritic equine fetlock cartilage tissues in organ culture. Arthritic tissues were more sensitive to PSGAG stimulation. The rates of cartilage-specific type-II collagen and chondroitin sulfate-rich glycosaminoglycan synthesis by confluent chondrocyte cell cultures obtained from normal and arthritic equine cartilage tissues were increased by 25 and 50 mg of PSGAG/ml. Cells from arthritic cartilage were also more sensitive to the presence of PSGAG. In addition, conce...
Richardson DW, Clark CC.Using arthroscopic technique, identical diameter defects were created in the proximal articular surface of both intermediate carpal bones of 6 horses. One of each pair of defects was deepened to penetrate the subchondral plate. Removed cartilage was assayed for [35S] sulfate incorporation, total hexosamine content, and DNA content. Six weeks later, cartilage was harvested and similarly analyzed from the distolateral portion of the radius directly opposite the created lesions and the distomedial portion of the radius distant from the lesion. The repair tissue filling the full-thickness defect a...
van den Heuvel LP, van den Born J, Veerkamp JH, Janssen GH, van de Velden TJ, Monnens LA, Schröder CH, Berden JH.1. Proteoglycans extracted from human and equine glomerular basement membranes (GBM) were purified by ion-exchange chromatography and gel filtration. 2. The glycoconjugates had an apparent molecular mass of 200-400 kDa and consisted of 75% protein and 25% glycosaminoglycan. Glycosidase and HNO2 treatment and the amino sugar and sulfate composition of both proteoglycan preparations identified heparan sulfate (HS) as the predominant saccharide chain. 3. Hydrolysis with trifluoromethanesulfonic acid yielded comparable core proteins with molecular masses of ca 160 and 120 kDa. 4. The HS chains had...
Patterson SD, Bell K.The carbohydrate side chains of the major plasma serpins of the horse and wallaby have been characterized by lectin analyses of protein blots from two-dimensional gels using the major human plasma serpin, alpha 1-protease inhibitor, as a control. Eight lectins were used in the characterization in conjunction with enzymatic deglycosylation of complex and high mannose side chains, chemical desialylation and defucosylation, and one round of 'Smith degradation', all being performed on the nitrocellulose blots. Assuming a standard complex side chain structure, the results of the 21 lectin/treatment...
Gustafson SB, McIlwraith CW, Jones RL.Four groups of 8 horses each had 1 midcarpal joint injected with 33 colony-forming units (CFU) of viable Staphylococcus aureus plus: 1 ml of saline solution (group 1, control), 250 mg of polysulfated glycosaminoglycan (PSGAG, group 2), 100 mg of methylprednisolone acetate (group 3), or 20 mg of sodium hyaulronate (group 4). Horses were euthanatized, and samples were obtained on the basis of clinical signs of septic arthritis that were nonresponsive to phenylbutazone administration. One group-1 horse, all 8 group-2 horses, 3 group-3 horses, and 4 group-4 horses were culture-positive for S aureu...
Gustafson SB, McIlwraith CW, Jones RL, Dixon-White HE.Polysulfated glycosaminoglycan (PSGAG) recently have been reported to potentiate the infectivity of Staphylococcus aureus in horses with experimentally induced septic arthritis. Four groups of 8 horses each had 1 midcarpal joint injected with approximately 33 viable colony-forming units (CFU) of S aureus plus either 1 ml of saline solution (group 1), 250 mg of PSGAG (group 2), 250 mg of PSGAG passed through a 0.6-microns filter (group 3), or 250 mg of PSGAG plus 125 mg of amikacin (group 4). Horses that developed clinical signs consistent with sepsis were euthanatized, and samples were collect...
Welch RD, DeBowes RM, Liepold HW.To evaluate the effects of intra-articular injection of dimethylsulfoxide (DMSO) on normal equine articular structures, 7 adult horses with clinically normal carpi were allotted to 2 treatment groups (group A, n = 4; group B, n = 3). In each horse after collection of synovial fluid samples, the right antebrachial carpal and middle carpal joints were aseptically injected with 2 ml of a 40% solution of 90% medical grade DMSO in lactated Ringer solution, and the corresponding joints of the left forelimb (controls) were injected with 2 ml of lactated Ringer solution. In group-A horses, 2 ml of syn...
Trotter GW, Yovich JV, McIlwraith CW, Norrdin RW.The effect of intramuscular polysulfated glycosaminoglycan (PSG) on repair of cartilage injury was evaluated in eight horses. In each horse, one middle carpal joint had both a partial-thickness and a full-thickness articular cartilage defect created. In the contralateral middle carpal joint, chemical articular cartilage injury was created by intra-articular injection of 50 mg sodium monoiodoacetate (MIA). Horses were divided into two groups for treatment. Group 1 horses (control) received an intramuscular injection of normal saline every four days for a total of seven injections starting seven...
Damm JB, Voshol H, Hård K, Kamerling JP, Vliegenthart JF.The carbohydrate chains of equine fibrinogen were enzymatically released by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F. The oligosaccharides obtained were fractionated by a combination of FPLC and HPLC and analyzed by 500-MHz 1H-NMR spectroscopy. Four monosialo and four disialo diantennary N-acetyllactosamine type of carbohydrate chains occur: (formula; see text)
Verde C, Ferrante M, Simpson MI, Babusci M, Broglia G, Landoni MF.Twelve healthy horses were subject to the monoioidoacetate (MIA) carpitis model, which was allowed to develop for 7 days. The horses were then randomly divided into two groups. Group A (control) received an intramuscular injection of normal saline every 4 days for a total of seven injections while group B received 500 mg of a PSGAG (SYNTEX CSY36) intramuscularly every 4 days for seven treatments. Efficacy of the PSGAG was evaluated by three clinical outcomes: lameness score, carpal circumference and maximum carpal flexion. Clinical outcomes were measured on days -8 (previous to carpitis induct...
Desantis S, Ventriglia G, Zizza S, De Santis T, Di Summa A, De Metrio G, Dell'aquila ME.Equine cumulus-oocyte complexes (COCs) were analyzed by means of 13 lectins to evaluate their glycoconjugate patterns and to verify differences between COCs recovered with compact (Cp) and expanded (Exp) cumulus. Cumulus cells showed a similar staining pattern in both Cp and Exp COCs with all lectins used, except for a higher reactivity with SNA and GSA II in Cp COCs and SBA in Exp COCs. The zona pellucida (ZP) showed (1) uniform staining with MAL II, RCA(120), and SBA in both Cp and Exp COCs, (2) trilaminar binding pattern with WGA as well as higher Con A reactivity in the outer region of bot...
Patterson SD, Bell K.The carbohydrate side chains of the major plasma serpins of the horse and wallaby have been characterized by lectin analyses of protein blots from two-dimensional gels using the major human plasma serpin, alpha 1-protease inhibitor, as a control. Eight lectins were used in the characterization in conjunction with enzymatic deglycosylation of complex and high mannose side chains, chemical desialylation and defucosylation, and one round of 'Smith degradation', all being performed on the nitrocellulose blots. Assuming a standard complex side chain structure, the results of the 21 lectin/treatment...
Klohnen A, Wilson DG, Hendrickson DA, Cooley AJ, MacWilliams PS.To evaluate the bactericidal properties of chlorhexidine diacetate (CHD) after potentiation with EDTA and Tris buffer (EDTA-Tris), and to find a potentiated CHD concentration that would achieve 90 to 100% killing for all bacteria tested. Methods: 6 adult ponies. Methods: Serial dilutions of CHD, CHD in EDTA-Tris and EDTA-Tris alone were evaluated for bactericidal activity against Staphylococcus aureus, Escherichia coli, and Streptococcus zooepidemicus. The tarsocrural joints of 6 ponies were lavaged with either 1 L phosphate-buffered saline solution (control) or 1 L of 0.0005% CHD in EDTA-Tris...
Temple-Wong MM, Raleigh AR, Frisbie DD, Sah RL, McIlwraith CW.To assess whether the combination of hyaluronan, sodium chondroitin sulfate, and -acetyl-d-glucosamine (HCSG) lubricates articular cartilage in vitro and modulates joint lubrication in vivo. Methods: 16 healthy adult horses. Methods: The effects of HCSG injections on SF lubricant properties and joint health, immediately after injury and 2 weeks later, were analyzed by use an equine osteochondral fracture model of post-traumatic osteoarthritis (OA). Middle carpal joints of adult horses were randomly assigned to 1 of 4 surgical treatment groups as follows: normal nonsurgical group (n = 8), norma...
Saari H, Tulamo RM, Konttinen YT, Sorsa T.A high performance liquid chromatography (HPLC) procedure suitable for the simultaneous determination of the molecular size and concentration of macromolecular hyaluronate and proteoglycans in synovial fluid has been developed. Irrigation of the equine tarsocrural joint with 20 ml physiological saline (PSS) caused a mild inflammation with an increase of proteoglycans in the synovial fluid over the baseline arthrocentesis control sample. Proteoglycan and hyaluronate in the synovial fluid did not interact to form hyaluronate-proteoglycan aggregates, but separated as distinct chromatographic peak...
Khatibzadeh SM, Menarim BC, Nichols AEC, Werre SR, Dahlgren LA.Extracellular matrix (ECM) is responsible for tendon strength and elasticity. Healed tendon ECM lacks structural integrity, leading to reinjury. Porcine urinary bladder matrix (UBM) provides a scaffold and source of bioactive proteins to improve tissue healing, but has received limited attention for treating tendon injuries. The objective of this study was to evaluate the ability of UBM to induce matrix organization and tenogenesis using a novel in vitro model. We hypothesized that addition of UBM to tendon ECM hydrogels would improve matrix organization and cell differentiation. Hydrogels se...
Frisbie DD, Sandler EA, Trotter GW, McIlwraith CW.To determine response of interleukin-1alpha (IL-1alpha)-conditioned equine articular cartilage explants to insulin-like growth factor-1 (IGF-1). Sample Population-Cartilage from the trochlea and condyles of the femur of a clinically normal 4-year-old horse. Methods: Effects of IGF-1 (0 to 500 ng/ml) after addition of IL-1alpha were evaluated by assessing matrix responses, using a sulfated glycosaminoglycan (GAG) assay, matrix 35SO4 GAG incorporation, and release of GAG. Mitogenic response was assessed by 3H-thymidine incorporation into DNA and fluorometric assay of total DNA concentration. Res...
Chun J, Kang T, Seo JP, Jeong H, Kim M, Kim BS, Ahn M, Kim J, Shin T.Vomeronasal organ (VNO) is a tubular pheromone sensing organ in which the lumen is covered with sensory and non-sensory epithelia. This study used immunohistochemistry and lectin histochemistry techniques to evaluate developmental changes, specifically of the glycoconjugate profile, in the horse VNO epithelium. Immunostaining analysis revealed PGP9.5 expression in some vomeronasal non-sensory epithelium (VNSE) cells and in the vomeronasal receptor cells of the vomeronasal sensory epithelium (VSE) in fetuses, young foals, and adult horses. OMP expression was exclusively localized in receptor ce...
Gurusinghe S, Hilbert B, Trope G, Wang L, Bandara N, Strappe P.Immortalization of chondrocytes enables long term in vitro culture; however, the chondrogenic capacity of transformed cells varies, thus highlighting the need to develop a proliferative and tuneable chondrocyte cell line where hypertrophic differentiation can be controlled. In this study the SV40 large T antigen and human telomerase reverse transcriptase were employed to immortalize pooled equine chondrocytes through lentiviral vector mediated transduction either singly or on combination. Transformed chondrocytes proliferated stably over multiple passages, but resulted in significantly lower e...
Barnewitz D, Evers A, Zimmermann J, Wilke I, Kaps C, Sittinger M.Degenerative alterations in fetlock joints of the forelimb are common diagnoses for horses. The hyaline cartilage has a low capacity to regenerate and the treatment by veterinarians is often insufficient. As a final result, horses with articular cartilage defects are often not able to take part in competitions anymore. To establish an autologous cartilage repair method, we set artificial lesions (8 mm in diameter) into the fetlock joints of the forelimb of three horses. These defects were closed with autologous chondrocyte implants, which were fixed with titan-suture-anchors. After 3, 12 and 2...
Gnanesh Kumar BS, Rawal A.Secretory immunoglobulin A (sIgA) is the major antibody present in the human milk where it confers passive immunity to neonates. Other than human, non-ruminants such as equine, swine etc., also possess sIgA in milk but detailed characterization is limited. In the present study, we characterized sIgA from donkey milk for amino acid sequence and N-glycosylation through LC-MS/MS analysis. The complete amino acid sequence of alpha chain constant region (C) was elucidated. The sequence analysis of variable regions (V and V) and light chain constant region (C) showed several amino acid substitutions...
Jones CJ, Enders AC, Wooding FP, Dantzer V, Leiser R, Stoddart RW.Using lectin histochemistry on plastic-embedded material, the glycosylation patterns of equine girdle and cup cells, and associated endometrial glands, have been investigated from 37 to 67 days gestation. Results were compared with the glycosylation of the 50-day allantochorionic trophoblast of the established equine placenta that will later form the microcotyledons. The differentiated cup cells, which secrete equine chorionic gonadotropin (eCG), showed a pattern of glycosylation that was distinct both from the progenitor girdle cells and the allantochorionic trophoblast, with granules that bo...
Du J, Eddington N.A sensitive and selective HPLC method for the determination of the disaccharides of chondroitin sulfate in horse and dog plasma was validated. Chondroitin sulfate is degraded by chondroitinase ABC to three primary unsaturated disaccharides, (1) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-D-galactose, (2) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose, and (3) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose, when treated with chondroitinase. Plasma samples (0.5 ml) were treated with 50 mU of chon...
Vergara-Hernandez FB, Panek CL, Nielsen BD, Robison CI, Colbath AC.To determine the effects of clodronate disodium (CLO) on control and recombinant equine interleukin-1β (IL-1β)-treated equine joint tissues. Methods: In vitro experimental study. Methods: Cartilage explants, chondrocytes, and synoviocytes (n = 3 horses). Methods: Monolayer cultures of chondrocytes and synoviocytes from three horses were subjected to: control media (CON), 5 ng/ml CLO (C/low), 50 ng/ml CLO (C/med), 100 ng/ml CLO (C/high), with and without IL-1β, and 10 ng/ml IL-1β (IL) alone for 72 hours. Cartilage explants from three horses were subjected to CON, IL, C/low, and C/...
Sandler EA, Frisbie DD, McIlwraith CW.Previous in vitro pilot studies have defined a potentially beneficial effect of insulin-like growth factor-1 (IGF-1) and triamcinolone acetonide (TA) on interleukin-1 (IL-1)-conditioned equine cartilage. Furthermore, an optimal dose for IGF-1 treatment alone has been documented previously using the same test system as in the current project. Objective: To perform a dose titration of TA on IL-1-conditioned equine articular cartilage explants in the presence of an optimised IGF-1 dose, in order to optimise a triamcinolone concentration for use in combination with IGF-1 for future investigations....
Yeung CC, Svensson RB, Mogensen NMB, Merkel MFR, Schjerling P, Jokipii-Utzon A, Zhang C, Carstensen H, Buhl R, Kjaer M.Physical activity can activate extracellular matrix (ECM) protein synthesis and influence the size and mechanical properties of tendon. In this study, we aimed to investigate whether different training histories of horses would influence the synthesis of collagen and other matrix proteins and alter the mechanical properties of tendon. Samples from superficial digital flexor tendon (SDFT) from horses that were either (a) currently race trained (n = 5), (b) previously race trained (n = 5) or (c) untrained (n = 4) were analysed for matrix protein abundance (mass spectrometry), collage...
Hu L, Li X, Li C, Wang L, Han L, Ni W, Zhou P, Hu S.The gut microbiota is a treasure trove of carbohydrate-active enzymes (CAZymes). To explore novel and efficient CAZymes, we analyzed the 4,142 metagenome-assembled genomes (MAGs) of the horse gut microbiota and found the MAG117.bin13 genome (Bacteroides fragilis) contains the highest number of polysaccharide utilisation loci sites (PULs), indicating its high capability for carbohydrate degradation. Bioinformatics analysis indicate that the PULs region of the MAG117.bin13 genome encodes many hypothetical proteins, which are important sources for exploring novel CAZymes. Interestingly, we discov...
McCarthy MB, Duesterdieck-Zellmer KF, Larson MK.To determine whether Botulinum neurotoxin type A (BoNT-A) ameliorates the effects of interleukin 1 (IL-1) on equine articular cartilage, or exerts negative effects on normal equine articular cartilage homeostasis in vitro. Methods: Articular cartilage explants from 6 healthy femoropatellar joints of 3 adult horses. Methods: Explants were allocated to the IL-1 challenged or unchallenged group, then exposed to 1 of 6 concentrations of BoNT-A (0, 1, 10, 50, 100, or 500 pg/mL) for 96 hours. To assess BoNT-A's effects on inflammation, prostaglandin E2 (PGE2) was measured in media via ELISA. Matrix ...
Collins EA.Four cases of equine lameness were treated with intra-articular polysulphated glycosaminoglycan. Two, two-year-old flat racers were treated conservatively after traumatic injury. They subsequently became lame owing to the formation of new bone and osteophytes. Two older steeplechasers were lame owing to degenerative joint disease. The four horses were treated with intra-articular injections of polysulphated glycosaminoglycans and, after three or four injections, they became clinically sound and were able to continue racing with varying degrees of success.
Fuller CJ, Barr AR, Dieppe PA, Sharif M.An epitope of keratan sulphate (KS) and total glycosaminoglycans (GAG) were measured in synovial fluid samples from joints of 53 horses immediately following humane destruction. Internal examination of the joints post mortem ensured that there was no gross evidence of osteoarthritis or other joint disease. Joints sampled were distal interphalangeal (DIP), proximal interphalangeal (PIP), metacarpophalangeal (MCP), metatarsophalangeal (MTP), tarsometatarsal (TMT), tarsocrural (TC), femoropatellar (FP) and antebrachiocarpal (ABC) joints. The age of each horse was assessed by examination of the te...
Oikawa M, Kaneko M, Yoshikawa T.To elucidate the pathomorphogenesis of extremely shortened small-intestinal villi, occurring spontaneously in neonatal foals, the morphology of the small intestine with stunted villi was studied in eight cases. All intestinal wall elements and the villi were poorly developed. Most villi were found to be extremely short throughout the entire length of the small intestine. The villous core consisted of undifferentiated, fibroblast-like cells held loosely together by ground substance which was rich in glycosaminoglycan. Development of the villous lamina propria was poor with respect to capillarie...
Whyte A, Allen WR.Pre- and post-implantation endometrial tissue was removed from equids at known stages of pregnancy. Thin sections of this material were reacted with fluorescein conjugates of several lectins. Two lectins in particular, with specificities for L-fucose and N-acetylglucosamine, reacted strongly with the endometrial epithelium. The reaction for N-acetylglucosamine occurred in small patches on the endometrial epithelium and extended to cover the entire epithelial surface and endometrial glands after implantation. L-Fucose was observed in larger surface deposits particularly at the openings of endom...
Nixon AJ, Krook LP, Roth JE, King JM.A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. After euthanasia at week 8, the treated and control joints were examined for gross changes, and samples of cartilage and subchondral bone, synovial membrane, and peripheral lymph nodes were examined histologically. Depletion of cartilage ma...
MacDonald MH, Benton HP.To determine the influence of activated equine neutrophils on sulfated glycosaminoglycan metabolism of equine articular cartilage in vitro. Methods: Articular cartilage explants harvested from the metacarpophalangeal joints of 7 horses. Methods: Proteoglycan degradation and synthesis were measured by release of glycosaminoglycan from the explants, and incorporation of [35S]sulfate into newly synthesized glycosaminoglycan. Results: Activated equine neutrophils significantly increased the release of glycosaminoglycan from explant matrix and the magnitude of that response was influenced by durati...
Brama PA, Barneveld A, Karssenberg D, Van Kampen GP, van Weeren PR.A recently developed indenter system that aims at determination of local structural properties of the cartilage surface was evaluated for suitability in the horse. To this aim, maximum indenter force was measured of the articular surface and related to biochemical characteristics of the cartilage at different sites of the distal metacarpal bone (MC). Significant topographical variation exists in structural properties of the articular surface of the MC. The dorsal margin showed a significantly lower maximum indenter force than more centrally located areas, indicating an increased compliance und...
Barr AR, Duance VC, Wotton SF, Waterman AE.The influence of repeated intra-articular injections of sodium hyaluronate and polysulphated glycosaminoglycan on the repair of full-thickness osteochondral defects was examined in the midcarpal joints of ponies. The study showed no significant difference between treated and control groups with regard to total collagen content, uronic acid content or the relative proportions of Type I and Type II collagen in the repair tissue, indicating that the drugs did not affect the biochemical composition of the repair tissue 11 weeks after defect induction.
Okumura M, Fujinaga T.The role of keratan sulphate (KS) as a metabolic marker of cartilage was evaluated using an in vitro model of equine articular cartilage. Articular cartilage was harvested from clinically healthy 6-month-old foals (n = 3). Chondrocytes were centrifuged and cultured as pellets. Chondrocyte pellets were stimulated by insulin-like growth factor-I alpha (IGF-I alpha) or interleukin-1 alpha (IL-1 alpha) for 2 weeks. The concentrations of sulphated glycosaminoglycans (GAG) and KS in the culture media were measured by a 1,9-dimethyl-methylene blue (DMMB) colorimetric assay and an inhibition enzyme-li...
Lettry V, Kawasaki H, Sugaya K, Hosoya K, Takagi S, Okumura M.This study aimed to evaluate a system that identifies cartilage turn over and/or degradation through measurement of a new keratan sulfate (KS) epitope concentration in equine sera. Blood samples were collected from 30 horses, 1 (n = 15) and 2 year-olds (n = 15). Serum samples were analyzed for an epitope of keratan sulfate by 1/20/5D4 (KS5D4) and new epitopes of keratan sulfate using high sensitive keratan sulfate (HSKS), measured by two respective enzyme-linked immunosorbant assays (ELISAs). There was no correlation in serum concentration of KS evaluated using 5D4 and HSKS. Age had no signifi...
