The extracellular matrix (ECM) in horses is a complex network of proteins and polysaccharides that provides structural and biochemical support to surrounding cells. It is a dynamic entity involved in various physiological processes, including tissue repair, development, and homeostasis. In equine biology, the ECM is composed of components such as collagen, elastin, proteoglycans, and glycoproteins, which contribute to the integrity and functionality of tissues like cartilage, tendons, and skin. Alterations in the ECM can influence cellular behavior and are associated with conditions such as osteoarthritis and tendon injuries. This page aggregates peer-reviewed research studies and scholarly articles that explore the composition, function, and implications of the extracellular matrix in equine health and disease.
Fortier LA, Balkman CE, Sandell LJ, Ratcliffe A, Nixon AJ.This study evaluated the constitutive insulin-like growth factor-I (IGF-I) gene expression pattern in spontaneously healing cartilage defects over the course of 16 weeks, and correlated the tissue morphology and matrix gene expression with IGF-I mRNA levels. Full-thickness 15 mm cartilage defects were debrided in the femoral trochlea of both femoropatellar joints of 8 horses and the healing defects examined 2, 4, 8, or 16 weeks after surgery. Samples were harvested for histologic assessment of tissue healing using H&E staining, toluidine blue histochemical reaction for proteoglycan deposition,...
Worster AA, Brower-Toland BD, Fortier LA, Bent SJ, Williams J, Nixon AJ.This study evaluated chondrogenesis of mesenchymal progenitor stem cells (MSCs) cultured initially under pre-confluent monolayer conditions exposed to transforming growth factor-beta1 (TGF-beta1), and subsequently in three-dimensional cultures containing insulin-like growth factor I (IGF-I). Bone marrow aspirates and chondrocytes were obtained from horses and cultured in monolayer with 0 or 5 ng of TGF-beta 1 per ml of medium for 6 days. TGF-beta 1 treated and untreated cultures were distributed to three-dimensional fibrin disks containing 0 or 100 ng of IGF-I per ml of medium to establish fou...
Brooks DE, Komaromy AM, Garcia-Fernandez MC, Cutler TJ, Samuelson DA, Kallberg ME.Purpose To use immunohistochemical techniques to identify and localize the structural macromolecules of the extracellular matrix (ECM) of the normal adult equine lamina cribrosa in order to make comparisons to the extracellular matrix of the lamina cribrosa of horses with glaucoma. METHODS: Normal eyes of five adult horses between 5 and 10 years of age were fixed in 10% neutral buffered formalin and embedded in paraffin. Polyclonal rabbit-derived antibodies against human elastin, laminin, fibrillin-1, and collagen types I, III and IV, and polyclonal goat-derived antibodies against collagen typ...
Song L, Ryan PL, Porter DG, Coomber BL.Relaxin participates in extracellular matrix (ECM) remodeling in many reproductive organs, including the ovary, by regulating proteolytic enzyme activity. Accumulated evidence indicates this action of relaxin is involved in ovarian follicle development and ovulation. Equine follicles are embedded in cortex that is at the center of the ovary and they must expand/emigrate to the fossa, the only site in the ovary for ovulation. Due to the tremendous expansion of the follicle in this species, we hypothesized that ovarian stromal remodeling would be extensive. Therefore, cultured equine ovarian str...
Riley SC, Gibson AH, Leask R, Mauchline DJ, Pedersen HG, Watson ED.Extensive tissue remodelling is required in equine ovaries for follicle growth and development and also migration of the follicle to the ovulatory fossa, where ovulation occurs. The mechanisms for these processes are largely unexplored. Matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs) are important for control of breakdown of extracellular matrix during tissue remodelling. The aims of this study were to determine the pattern and sites of secretion of the gelatinases MMP-2 and -9 and TIMPs into follicular fluid during follicle development in mare ovaries. The pred...
Walter I, Handler J, Reifinger M, Aurich C.Periglandular fibrosis and cystic dilation of uterine glands are associated with equine endometriosis. The presence of extracellular matrix proteins (collagen type I, III and IV, laminin and fibronectin) in healthy and endometriotic specimens was demonstrated by immunohistochemistry. The distribution of collagen I, but not collagen III, was dependent on the stage of the oestrous cycle. The arrangement of collagen I and collagen III in endometriotic specimens was similar to that in normal endometrium. In periglandular fibrosis, collagen IV, laminin and fibronectin deposition outside the basemen...
Davenport CL, Boston RC, Richardson DW.To investigate the effects of enrofloxacin and magnesium deficiency on explants of equine articular cartilage. Methods: Articular cartilage explants and cultured chondrocytes obtained from adult and neonatal horses. Methods: Full-thickness explants and cultured chondrocytes were incubated in complete or magnesium-deficient media containing enrofloxacin at concentrations of 0, 1, 5, 25, 100, and 500 microg/ml. Incorporation and release of sulfate 35S over 24 hours were used to assess glycosaminoglycan (GAG) synthesis and degradation. An assay that measured binding of dimethylmethylene blue dye ...
Brama PA, Tekoppele JM, Bank RA, van Weeren PR, Barneveld A.This study aimed to examine whether biochemical characteristics of juvenile articular cartilage are changing during the first year post partum and whether they can be influenced by exercise at young age. Water, glycosaminoglycan (GAG), DNA, total collagen, hydroxylysine and hydroxylysylpyridinoline (HP) content were measured in articular cartilage of 43 foals that were subdivided into 3 groups (n = 15, 14 and 14) which were subjected to different exercise regimens from one week after birth to age 5 months. At the age of 5 months all foals were weaned and 8 foals were selected randomly from eac...
van den Hoogen BM, van de Lest CH, van Weeren PR, van Golde LM, Barneveld A.In osteochondrosis (OC) the process of endochondral ossification is impaired. Proteoglycans form one of the major components of the extracellular matrix of cartilage and are able to bind calcium. For this reason, proteoglycans are thought to play an important role early in the mineralisation process and may, therefore, be important in the pathogenesis of OC. To investigate possible differences in proteoglycan metabolism, normal and osteochondrotic articular-epiphyseal cartilage was harvested from the hock and stifle joints of 43 foals age 5 and 11 months. The samples were cultured as explants ...
Brama PA, Tekoppele JM, Bank RA, Karssenberg D, Barneveld A, van Weeren PR.The aim of this study was to evaluate topographical differences in the biochemical composition of the extracellular matrix of articular cartilage of the normal equine fetlock joint. Water content, DNA content, glycosaminoglycan (GAG) content and a number of characteristics of the collagen network (total collagen content, levels of hydroxylysine- (Hyl) and the crosslink hydroxylysylpyridinoline, (HP) of articular cartilage in the proximal 1st phalanx (P1), distal 3rd metacarpal bone (MC), and proximal sesamoid bones (PSB) were determined in the left and right fetlock joint of 6 mature horses (a...
Smith RK, Heinegård D.Cartilage oligomeric matrix protein (COMP) is a noncollagenous extracellular matrix protein found predominantly in cartilage, but also in tendon, ligament and meniscus. Studies in man have demonstrated that it may be used as a prognostic marker in rheumatoid arthritis and osteoarthritis. The present study investigated whether tendon injury contributes to serum and tendon sheath synovial fluid levels of COMP in horses. COMP levels, analysed by competitive ELISA, in the digital sheath synovial fluid were more than 10-fold higher than in the serum. Levels were significantly raised when tendon dam...
Herrler A, Stewart F, Crossett B, Pell JM, Ellis PD, Beier HM, Allen WR.An acellular embryonic capsule envelops equine conceptuses between day 6 and day 23 after ovulation. As all of the factors mediating embryo-mother signalling must pass through the capsule, it acts like a 'mailbox'. Therefore, we have started to map the proteins in this special extracellular matrix at the interface between mother and embryo. In the present study, one- and two-dimensional gel electrophoresis were used to examine a range of proteins. Use of western blotting identified three specific proteins in the capsules of equine conceptuses recovered on day 16 after ovulation: insulin-like g...
Birch HL, Bailey JV, Bailey AJ, Goodship AE.Specific tendons show a high incidence of partial central core rupture which is preceded by degeneration. In the performance horse, the superficial digital flexor tendon (SDFT) is most often affected. We have described previously the molecular changes that are associated with degeneration in the central core region of the equine SDFT. The pathophysiological mechanism leading to change in synthetic activity of central zone cells in degenerated tendons is not known. In this study, we test the hypothesis that ageing results in matrix composition changes within the central zone of the SDFT. Extrac...
Carver SE, Heath CA.Equine articular chondrocytes, embedded within a polyglycolic acid nonwoven mesh, were cultured with various combinations of intermittent pressure, fluid flow, and mixing to examine the effects of different physical stimuli on neochondrogenesis from young cells. The cell/polymer constructs were cultured first in 125 ml spinner flasks for 1, 2, or 4 weeks and then in a perfusion system with intermittent pressure for a total of up to 6 weeks. Additional constructs were either cultured for all 6 weeks in the spinner flasks or for 1 week in spinners followed by 5 weeks in the perfusion system with...
Hess S, Gulati R, Peluso JJ.The present studies showed that sequential treatment with equine CG (eCG) and hCG not only induced an increase in ovarian weight, but also caused an estimated 4.6-fold increase in the number of ovarian surface epithelial cells. In addition, eCG-hCG treatment increased ovarian hepatocyte growth factor (HGF) messenger RNA levels. These studies also demonstrated that rat primary ovarian surface epithelial cells as well as a cell line derived from rat ovarian surface epithelium (i.e. ROSE-179 cells) do not express the LH (hCG) receptor. Both of these cells express c-Met, the receptor for HGF. To a...
Jeffcott LB, Henson FM.The importance of osteochondrosis (dyschondroplasia) to the horse industry has been well documented since it was first recorded 50 years ago. The condition is known to be multifactorial in origin, arising from focal failure of endochondral ossification at predilection sites in articular/epiphyseal growth cartilage, but specific information on its aetiopathogenesis is sparse. This paper reviews the current knowledge of growth cartilage metabolism and the process of normal endochondral ossification in the horse. It highlights the localization of various protein products of chondrocytes and the d...
Song L, Porter DG, Coomber BL.Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) play very important roles in extracellular matrix (ECM) remodeling in ovarian follicle growth and ovulation. Equine follicles are embedded in cortex that is at the center of the ovary, and they must expand/emigrate to the fossa, the only site in the ovary for ovulation. Therefore, equine ovarian stromal cells (EOSC) are probably involved in ECM remodeling during follicle growth. This study examined whether cultured EOSC synthesize gelatinases and TIMPs, molecules essential for ECM remodeling in other systems. Results showed...
Birch HL, Bailey AJ, Goodship AE.Injuries to the superficial digital flexor tendon are common in horses required to gallop and jump at speed. Partial rupture of this tendon usually occurs in the central core of the midmetacarpal region and may be preceded by localised degenerative changes. Post mortem examination of apparently normal equine flexor tendons has revealed an abnormal macroscopic appearance in the central core, characterised by a reddish discolouration. We have previously shown that there is also physical damage to the collagen fibres. In the present study we tested the hypothesis that the abnormal appearance is a...
Clegg PD, Jones MD, Carter SD.Loss of articular cartilage, which is the most important pathological lesion occurring in osteoarthritis, has been shown to be enzymatically mediated. The matrix metalloproteinases (MMPs) are a group of enzymes which have been implicated in this degradation of articular cartilage matrix. The use of pharmacological agents to inhibit this catabolic process in the joint is a potential route for therapeutic intervention. The gelatinase MMPs, MMPs-2 and 9, were purified by affinity chromatography from equine cell cultures. The ability of phenylbutazone, flunixin, betamethasone, dexamethasone, methy...
Fortier LA, Nixon AJ, Williams J, Cable CS.To isolate mesenchymal stem cells from adult horses and determine specific monolayer culture conditions required to enhance biochemically and phenotypically defined chondrocytic differentiation. Methods: 2 adult horse bone marrow donors without skeletal or hematologic abnormalities. Methods: Bone marrow was aspirated from the sternebra, and mesenchymal stem cells were isolated by centrifugation and cultured in monolayers. Subcultures were established in 24-well plates on day 13. Culture medium was harvested every 2 days, and culture of 12 of the 24 wells was terminated on day 6 and of the rema...
Johnson PJ, Tyagi SC, Katwa LC, Ganjam VK, Moore LA, Kreeger JM, Messer NT.Samples of connective tissue obtained from the hoof of six laminitic and eight non-laminitic adult horses were analysed zymographically to investigate whether connective tissue matrix metalloproteinases are activated or induced during laminitis. The activity or matrix metalloproteinases was substantially greater in the tissues from the laminitic horses than in the tissues from the non-laminitic horses. A comparison of the collagenolytic activity in the laminitic and control tissues showed that collagenolytic activities corresponding to the 92 kDa (P < 0.001), 72 kDa (P < 0.01) and 66 kDa (P < ...
Platt D, Bird JL, Bayliss MT.In order to identify the pathological processes involved in the destruction of articular cartilage in arthritic diseases, it is first necessary to characterise the normal homeostasis of cartilage in a healthy joint. In particular, normal age-related changes in the biochemistry of cartilage complicate any comparisons that are made between diseased and healthy tissue. There are, however, no reports in the literature detailing the influence of ageing on the biochemistry of proteoglycans in equine articular cartilage. This study addresses the absence of such information by investigating the struct...
Cochrane CA.Abstract Wound models attempt to simulate the natural healing processes in wounds. However, all models have significant limitations due to the complexity of the tissue repair process. Much can be learned from wound models in vitro by the use of cell culture techniques. The horse can provide a suitable naturally occurring model of chronic wound healing because it has many similarities to wound healing encountered in human medicine. The tissue architecture was investigated with regard to extracellular matrix and growth factor distribution during wound healing and growth factors were consisten...
Henson FM, Davies ME, Jeffcott LB.This study describes (1) the histological appearance of dyschondroplasia, the primary lesion of osteochondrosis, in articular cartilage of the horse and (2) the localization of type VI collagen which is an important constituent of the extracellular matrix (ECM). Dyschondroplastic cartilage was identified on the basis of the presence of cartilage cores (i.e., cartilage extending into the subchondral bone) and confirmed with subsequent histological examination. Full-thickness cartilage samples from 57 horses were collected and paraffin embedded. Histological examination was used to examine the n...
Fortier LA, Nixon AJ, Mohammed HO, Lust G.To determine the effects of transforming growth factor-beta 1 (TGF-beta 1) on the synthesis of DNA, collagen, and proteoglycans (PG) by equine chondrocytes. Methods: Articular cartilage obtained from multiple joints of a 4-month-old foal. Methods: Chondrocytes were isolated by collagenase digestion, cultured in monolayer, trypsinized, and implanted at a cellular density of 10 x 10(6) chondrocytes/ml in a three-dimensional fibrin matrix. Chondrocytes in culture were supplemented with TGF-beta 1 at concentrations of 0, 1, 5, or 10 ng/ml in serum-free medium or medium containing fetal bovine seru...
Platt D, Wells T, Bayliss MT.Equine chondrocytes were cultured in vitro for 30 days in ionically gelled alginate beads. The alginate polymerises into a stable gel in the presence of divalent cations (calcium), and rapid depolymerisation in the presence of a calcium chelator releases the viable chondrocytes. The chondrocytes maintained a spherical appearance for 30 days in culture, in marked contrast to monolayer cultures, which develop a dedifferentiated fibroblastic morphology. The major proteoglycan molecule produced by the encapsulated chondrocytes was aggrecan, of similar hydrodynamic size to aggrecan molecules presen...
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...
Kawcak CE, Trotter GW, Frisbie DD, McIlwraith CW.To evaluate the effects of a commercially defined, serum-free medium additive on equine articular cartilage explants, compared with effects of serum-free and serum-supplemented media. Methods: Articular cartilage from a 3-year-old, mixed breed horse euthanatized for reasons other than musculoskeletal disease or sepsis. Methods: Media were changed every 48 hours, and the glycosaminoglycan (GAG) content was determined in media collected at each time point. Glycosaminoglycan synthesis by explant chondrocytes, and residual GAG content of articular cartilage (as a measure of explant GAG loss) were ...
Clarke EJ, Johnson E, Caamaño Gutierrez E, Andersen C, Berg LC, Jenkins RE, Lindegaard C, Uvebrant K, Lundgren-Åkerlund E, Turlo A, James V....Equine osteoarthritis (OA) is a heterogeneous, degenerative disease of the musculoskeletal system with multifactorial causation, characterized by a joint metabolic imbalance. Extracellular vesicles are nanoparticles involved in intracellular communication. Mesenchymal stem cell (MSC) therapy is a form of regenerative medicine that utilizes their properties to repair damaged tissues. Despite its wide use in veterinary practice, the exact mechanism of action of MSCs is not fully understood. The aim of this study was to determine the synovial fluid extracellular vesicle protein cargo following in...
Kisiday JD, Hale BW, Almodovar JL, Lee CM, Kipper MJ, Wayne McIlwraith C, Frisbie DD.Mesenchymal stem cells (MSCs) are present in low density in bone marrow and culture expansion is necessary to obtain sufficient numbers for many proposed therapies. Researchers have characterized MSC growth on tissue culture plastic (TCP), although few studies have explored proliferation on other growth substrates. Using adult equine MSCs, we evaluated proliferation on fibrinogen-rich precipitate (FRP) surfaces created from blood plasma. When seeded at 1 × 10(4) cells/cm(2) and passaged five times over 10 days, MSCs on FRP in medium containing fibroblast growth factor 2 (FGF2) resulted in a ...
Skiöldebrand E, Adepu S, Lützelschwab C, Nyström S, Lindahl A, Abrahamsson-Aurell K, Hansson E.This study aimed to test a novel treatment combination (TC) (equivalent to sildenafil, mepivacaine, and glucose) with disease-modifying properties compared to Celestone® bifas® (CB) in a randomized triple-blinded phase III clinical study in horses with mild osteoarthritis (OA). Joint biomarkers (reflecting the articular cartilage and subchondral bone remodelling) and clinical lameness were used as readouts to evaluate the treatment efficacy. Unassigned: Twenty horses with OA-associated lameness in the carpal joint were included in the study and received either TC (n = 10) or CB (n = ...
Clyne MJ.Proteoglycan degradation is central to the development of degenerative joint disease. Proteoglycans may be degraded by lysosomal enzymes from chondrocytes, synoviocytes or leucocytes. Collagen and matrix degradation occurs either by direct damage or due to degrading enzymes released into synovial fluid. Once the pathological sequence has begun it continues in a cyclic manner unless arrested by the ability of chondrocytes to synthesise sufficient matrix components. Treatment should ideally be directed to this end.
Miranda CMFC, Therrien J, Leonel LCPC, Smith OE, Miglino MA, Smith LC.Equine represents an attractive animal model for musculoskeletal tissue diseases, exhibiting much similarity to the injuries that occur in humans. Cell therapy and tissue bioengineering have been widely used as a therapeutic alternative by regenerative medicine in musculoskeletal diseases. Thus, the aim of this study was to produce an acellular biomaterial of equine skeletal muscle and to evaluate its effectiveness in supporting the in vitro culture of equine induced pluripotency stem cells (iPSCs). Biceps femoris samples were frozen at -20°C for 4 days and incubated in 1% sodium dodecyl s...
Höglund N, Nieminen P, Mustonen AM, Käkelä R, Tollis S, Koho N, Holopainen M, Ruhanen H, Mykkänen A.Equine asthma (EA) is an inflammatory disease of the lower airways driven by mediators released from cells. Extracellular vesicles (EVs) are vehicles for lipid mediators, which possess either pro-inflammatory or dual anti-inflammatory and pro-resolving functions. In this study, we investigated how the respiratory fatty acid (FA) profile reflects airway inflammatory status. The FA composition of bronchoalveolar lavage fluid (BALF), BALF supernatant, and bronchoalveolar EVs of healthy horses (n = 15) and horses with mild/moderate EA (n = 10) or severe EA (SEA, n = 5) was determined w...
Mayet A, Zablotski Y, Roth SP, Brehm W, Troillet A.Equine veterinarians face challenges in treating horses with osteoarthritic joint pain in routine veterinary practice. All common treatment options aim to reduce the clinical consequences of osteoarthritis (OA) characterized by persistent synovitis and progressive degradation of articular cartilage. A range of joint-associated cell types and extracellular matrices are involved in the not yet entirely understood chronic inflammatory process. Regeneration of articular tissues to re-establish joint hemostasis is the future perspective when fundamental healing of OA is the long-term goal. The use ...
Platt D, Wells T, Bayliss MT.Equine chondrocytes were cultured in vitro for 30 days in ionically gelled alginate beads. The alginate polymerises into a stable gel in the presence of divalent cations (calcium), and rapid depolymerisation in the presence of a calcium chelator releases the viable chondrocytes. The chondrocytes maintained a spherical appearance for 30 days in culture, in marked contrast to monolayer cultures, which develop a dedifferentiated fibroblastic morphology. The major proteoglycan molecule produced by the encapsulated chondrocytes was aggrecan, of similar hydrodynamic size to aggrecan molecules presen...
Garvican ER, Salavati M, Smith RKW, Dudhia J.The purpose of this study was to investigate the effect of normal synovial fluid (SF) on exposed endogenous tendon-derived cells (TDCs) and engrafted mesenchymal stem cells (MSCs) within the tendon extracellular matrix. Methods: Explants from equine superficial digital flexor (extra-synovial) and deep digital flexor tendons (DDFTs) from the compressed, intra-synovial and the tensile, extra-synovial regions were cultured in allogeneic or autologous SF-media. Human hamstring explants were cultured in allogeneic SF. Explant viability was assessed by staining. Proliferation of equine monolayer MSC...
Tangyuenyong S, Viriyakhasem N, Peansukmanee S, Kongtawelert P, Ongchai S.Cartilage erosion in degenerative joint diseases leads to lameness in affected horses. It has been reported that andrographolide from Andrographis paniculata inhibited cartilage matrix-degrading enzymes. This study aimed to explore whether this compound protects equine cartilage degradation in the explant culture model and to determine its effect on matrix metalloproteinase-2 (MMP-2) expression, a matrix-degrading enzyme, in equine chondrocyte culture. Equine articular cartilage explant culture was induced by 25 ng/mL interleukin-1β, a key inducer of cartilage degeneration, in cultures with...
Gabryś J, Kij-Mitka B, Sawicki S, Kochan J, Nowak A, Łojko J, Karnas E, Bugno-Poniewierska M.The in vitro maturation (IVM) of equine oocytes is still not efficient and does not yield consistent results. The specific requirements of equine oocytes during this process are still largely unknown, which hinders the development of assisted reproductive techniques (ART) in this species. Because the ovarian follicle microenvironment supports oocytes in their acquisition of developmental competence, follicular fluid seems to be a substantial source of bioactive factors that could support the IVM process. Extracellular vesicles (EVs) are cell-secreted molecules in body fluids that are able to ...
Khatibzadeh SM, Menarim BC, Nichols AE, 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 see...
Warnock JJ, Fox DB, Stoker AM, Beatty M, Cockrell M, Janicek JC, Cook JL.Introduction. Tissue engineering is a new methodology for addressing meniscal injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage formation, however, favorable in vitro culture conditions for synovium must be established in order to achieve this goal. The objective of this study was to determine cellularity, cell distribution, and extracellular matrix (ECM) formation of equine fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application in synovium-based meniscal tissue engineering. Scaffolds included open-cell poly-L-l...
van de Lest CH, Brama PA, van El B, DeGroot J, van Weeren PR.Osteochondrosis (OC) is the most important developmental orthopaedic disease in the horse. Despite some decades of research, much of the pathogenesis of the disorder remains obscure. Increasing knowledge of articular cartilage development in juvenile animals led to the presumption that the role of collagen in OC might be more important than previously thought. To study collagen characteristics of both cartilage and subchondral bone in young (5 and 11 months of age) horses, samples were taken of subchondral bone and articular cartilage from a group of 43 Dutch Warmblood foals and yearlings that...
Frontiers in allergyNovember 26, 2021
Volume 2 762026 doi: 10.3389/falgy.2021.762026
Ben Hamouda S, Miglino MA, de Sá Schiavo Matias G, Beauchamp G, Lavoie JP.Asthma is associated with increased deposition and altered phenotype of airway smooth muscle (ASM) cells. However, little is known about the processes responsible for these changes. It has been suggested that alterations of the extracellular matrix (ECM) contribute to the remodeling of ASM cells in asthma. Three-dimensional matrices allow the study of complex cellular responses to different stimuli in a close-to-natural environment. Thus, we investigated the ultrastructural and genic variations of ASM cells cultured on acellular asthmatic and control bronchial matrices. We studied horses, as ...
Mustonen AM, Lehmonen N, Oikari S, Capra J, Raekallio M, Mykkänen A, Paakkonen T, Rilla K, Niemelä T, Nieminen P.Osteoarthritis (OA) is a degenerative joint disease with inadequately understood pathogenesis leading to pain and functional limitations. Extracellular vesicles (EVs) released by synovial joint cells can induce both pro- and anti-OA effects. Hyaluronic acid (HA) lubricates the surfaces of articular cartilage and is one of the bioactive molecules transported by EVs. In humans, altered EV counts and composition can be observed in OA synovial fluid (SF), while EV research is in early stages in the horse-a well-recognized OA model. The aim was to characterize SF EVs and their HA cargo in 19 horses...
Wintz LR, Lavagnino M, Gardner KL, Sedlak AM, Arnoczky SP.To describe the effect of systemically administered oxytetracycline on the viscoelastic properties of rat tail tendon fascicles (TTfs) to provide a mechanistic rationale for pharmacological treatment of flexural limb deformities in foals. Methods: TTfs from ten 1-month-old and ten 6-month-old male Sprague-Dawley rats. Methods: 5 rats in each age group were administered oxytetracycline (50 mg/kg, IP, q 24 h) for 4 days. The remaining 5 rats in each age group served as untreated controls. Five days after initiation of oxytetracycline treatment, TTfs were collected and their viscoelastic properti...
Sedacca K, Samuelson D, Lewis P.To investigate the uveoscleral (US) pathway in the normal eyes of four domestic spp.: the cat, pig, cow and horse by examining the comparative anatomical structure of anterior US pathway. Methods: Four cats, ten pigs, four cows, eight horses. Methods: Formalin-preserved specimens from anterior uveas of the cat, pig, cow and horse were embedded and serially sectioned sagittally and tangentially and stained with H&E, Masson's trichrome, smooth muscle actin immunolabel, or elastin stain. Results: Spaces between the endings of the outer anterior ciliary body musculature (CBM) formed avenues fo...
Salinas P, Lira-Velásquez D, Bongiorno A, Sandoval C.The aim of this study was to quantify the distribution of aligned and non-aligned collagen in cross-sections of the superficial digital flexor tendon (SDFT) and deep digital flexor tendon (DDFT) in different levels of the distal forelimb of equines diagnosed with NS (Navicular Syndrome). Sixty equine forelimbs were collected. Was compared two groups (NA, Not affected vs. NS-group) by t-Student. Diagnosis of NS was based on clinical and lameness examination, diagnostic analgesia and radiological findings. The proportion of aligned and non-aligned collagens at 2 levels for the SDFT and 3 levels ...
Sun Y, Chen H, Kandel R, Hurtig M.Lesions in cartilage of equine weightbearing joints commonly result in lameness. Cell-based resurfacing techniques are currently being developed for human and veterinary applications. Biopsies of stifle joint cartilage (1 g) were harvested aseptically and chondrocytes were isolated by sequential enzyme digestion. The cells were grown in vitro on filter inserts. Analysis of cultures 8 weeks later showed that the cells had accumulated extracellular matrix and formed a continuous layer of cartilagenous tissue as determined histologically. The cells maintained their phenotype as they synthesised t...
El-Sheikh Ali H, Scoggin K, Murase H, Norris J, Menarim B, Dini P, Ball B.The equine chorioallantois (CA) undergoes complex physical and biochemical changes during labor. However, the molecular mechanisms controlling these changes are still unclear. Therefore, the current study aimed to characterize the transcriptome of equine CA during spontaneous labor and compare it with that of normal preterm CA. Placental samples were collected postpartum from mares with normal term labor (TL group, n = 4) and from preterm not in labor mares (330 days GA; PTNL group, n = 4). Our study identified 4137 differentially expressed genes (1820 upregulated and 2317 downregulat...
Bastos HB, Kretzmann NA, Santos GO, Esmeraldino AT, Rechsteiner SF, Mattos RC, Neves AP.The period from the emergence of a dominant follicle until its formation requires tissue remodeling. Enzymes promoting collagen lysis, such as matrix metalloproteinases (MMPs), are fundamental for the process of extracellular matrix remodeling, which allows changes in ovarian tissue architecture during follicular growth. It has been suggested that the production of these enzymes may be affected by the rise in circulating concentrations of LH, which acts on the ovarian surface epithelium (OSE). The aim of this study was to determine the expression of MMP-1, MMP-2, and LH receptor (LHR) in the o...
Brooks DE, Komaromy AM, Garcia-Fernandez MC, Cutler TJ, Samuelson DA, Kallberg ME.Purpose To use immunohistochemical techniques to identify and localize the structural macromolecules of the extracellular matrix (ECM) of the normal adult equine lamina cribrosa in order to make comparisons to the extracellular matrix of the lamina cribrosa of horses with glaucoma. METHODS: Normal eyes of five adult horses between 5 and 10 years of age were fixed in 10% neutral buffered formalin and embedded in paraffin. Polyclonal rabbit-derived antibodies against human elastin, laminin, fibrillin-1, and collagen types I, III and IV, and polyclonal goat-derived antibodies against collagen typ...
Doyle AJ, Stewart AA, Constable PD, Eurell JA, Freeman DE, Griffon DJ.To determine effects of sodium hyaluronate (HA) on corticosteroid-induced cartilage matrix catabolism in equine articular cartilage explants. Methods: 30 articular cartilage explants from fetlock joints of 5 adult horses without joint disease. Methods: Articular cartilage explants were treated with control medium or medium containing methylprednisolone acetate (MPA; 0.05, 0.5, or 5.0 mg/mL), HA (0.1, 1.0, or 1.5 mg/mL), or both. Proteoglycan (PG) synthesis was measured by incorporation of sulfur 35-labeled sodium sulphate into PGs, and PG degradation was measured by release of radiolabeled PGs...
Koch DW, Schnabel LV.Tendon injuries are common in both veterinary and human clinical patients and result in morbidity, pain, and lost athletic performance. Consequently, utilizing naturally occurring injuries in veterinary patients as a comparative model could inform the development of novel therapies and increase translation for the treatment of human tendon injuries. Mesenchymal stem cells (MSCs) have shown considerable efficacy for the treatment of experimental and clinical superficial digital flexor tendon injury in the horse; however, the reinjury rate following treatment can remain high and MSC efficacy in ...
Hortensius RA, Harley BA.The design of biomaterials for regenerative medicine can require biomolecular cues such as growth factors to induce a desired cell activity. Signal molecules are often incorporated into the biomaterial in either freely-diffusible or covalently-bound forms. However, biomolecular environments in vivo are often complex and dynamic. Notably, glycosaminoglycans (GAGs), linear polysaccharides found in the extracellular matrix, are involved in transient sequestration of growth factors via charge interactions. Biomaterials mimicking this phenomenon may offer the potential to amplify local biomolecular...
Clegg PD, Jones MD, Carter SD.Loss of articular cartilage, which is the most important pathological lesion occurring in osteoarthritis, has been shown to be enzymatically mediated. The matrix metalloproteinases (MMPs) are a group of enzymes which have been implicated in this degradation of articular cartilage matrix. The use of pharmacological agents to inhibit this catabolic process in the joint is a potential route for therapeutic intervention. The gelatinase MMPs, MMPs-2 and 9, were purified by affinity chromatography from equine cell cultures. The ability of phenylbutazone, flunixin, betamethasone, dexamethasone, methy...
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...
Koch DW, Schnabel LV, Ellis IM, Bates RE, Berglund AK.Mesenchymal stem cells (MSCs) secrete paracrine factors and extracellular matrix proteins that contribute to their ability to support tissue healing and regeneration. Both the transcriptome and the secretome of MSCs can be altered by treating the cells with cytokines, but neither have been thoroughly investigated following treatment with the specific cytokine transforming growth factor (TGF)-β2. RNA-sequencing and western blotting were used to compare gene and protein expression between untreated and TGF-β2-treated equine bone marrow-derived MSCs (BM-MSCs). A co-culture system was utilized t...
Marchant EA, Semevolos SA.The marginal transitional zone is peripherally located within the diarthrodial joint, and represents the interface of articular cartilage, periosteum, and the fibrous joint capsule. The purpose of this study is to characterize the protein expression of matrix and molecular regulators in the marginal transitional zone of foals having osteochondrosis (OC) compared to normal foals. Several families of proteins with known roles in cartilage and bone development are investigated, including matrix molecules, Wnt signaling, apoptotic factors and paracrine cell signaling molecules. Our results demonst...