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.
Almiñana C, Rudolf Vegas A, Tekin M, Hassan M, Uzbekov R, Fröhlich T, Bollwein H, Bauersachs S.Extracellular vesicles (EVs) have been identified in the uterine fluid in different species and have been pointed as key players in the embryo-maternal dialogue, maternal recognition of pregnancy and establishment of pregnancy. However, little is known about the uterine EVs in the mare. Therefore, the present study aimed at characterizing EVs from uterine lavage of cyclic mares by comparing five EVs isolation methods and the combination of them: (1) ultracentrifugation (UC); (2) concentration of lavage volume by Centricon ultrafiltration (CE); (3) the use of CE with different washing steps (ph...
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 ...
McCoy AM, Kemper AM, Boyce MK, Brown MP, Trumble TN.Post-traumatic osteoarthritis (PTOA) is a common and significant problem in equine athletes. It is a disease of the entire joint, with the synovium thought to be a key player in disease onset and progression due to its role in inflammation. The development of effective tools for early diagnosis and treatment of PTOA remains an elusive goal. Altered gene expression represents the earliest discernable disease-related change, and can provide valuable information about disease pathogenesis and identify potential therapeutic targets. However, there is limited work examining global gene expression c...
Ben Hamouda S, Vargas A, Boivin R, Miglino MA, da Palma RK, Lavoie JP.Severe asthma is associated with an increased airway smooth muscle (ASM) mass and altered composition of the extracellular matrix (ECM). Studies have indicated that ECM-ASM cell interactions contribute to this remodeling and its limited reversibility with current therapy. Three-dimensional matrices allow the study of complex cellular responses to different stimuli in an almost natural environment. Our goal was to obtain acellular bronchial matrices and then develop a recellularization protocol with ASM cells. We studied equine bronchi as horses spontaneously develop a human asthma-like disease...
Haythorn A, Young M, Stanton J, Zhang J, Mueller POE, Halper J.Equine degenerative suspensory ligament desmitis (DSLD) is a systemic connective tissue disorder first identified in Peruvian Paso horses but afflicting other horse breeds as well. Inappropriate accumulation of proteoglycans in connective tissues, most prominently in tendons and ligaments, leads to progressive and debilitating lameness and pain. It is largely unknown what drives the overproduction of proteoglycans, but our previous studies suggest involvement of bone morphogenetic protein 2 (BMP2), a member of the transforming growth factor-β (TGFβ) family, impacting synthesis of proteoglyca...
Navarrete F, Wong YS, Cabezas J, Riadi G, ManrÃquez J, Rojas D, Furlanetto Mançanares AC, Rodriguez-Alvarez L, Saravia F, Castro FO.Equine endometrial and adipose mesenchymal stem cells (eMSCs and aMSCs, respectively) were isolated from the same donors of thoroughbred mares. The cells displayed characteristic features of MSCs, including trilineage mesodermal and also neurogenic differentiation. We evaluated the influence of cellular origin on their transcriptome profile. Cellular RNA was isolated and sequenced and extracellular vesicles (EVs) were obtained from conditioned medium of cells cultured in medium depleted of EVs, and their microRNA (miRNA) cargo analyzed by sequencing. Differential expression of mRNAs and EV-miR...
Schmidt S, Abinzano F, Mensinga A, Teßmar J, Groll J, Malda J, Levato R, Blunk T.Identification of articular cartilage progenitor cells (ACPCs) has opened up new opportunities for cartilage repair. These cells may be used as alternatives for or in combination with mesenchymal stromal cells (MSCs) in cartilage engineering. However, their potential needs to be further investigated, since only a few studies have compared ACPCs and MSCs when cultured in hydrogels. Therefore, in this study, we compared chondrogenic differentiation of equine ACPCs and MSCs in agarose constructs as monocultures and as zonally layered co-cultures under both normoxic and hypoxic conditions. ACPCs a...
Zhang C, Svensson RB, Montagna C, Carstensen H, Buhl R, Schoof EM, Kjaer M, Magnusson SP, Yeung CC.Tendon is a highly organized, dense connective tissue that has been demonstrated to have very little turnover. In spite of the low turnover, tendon can grow in response to loading, which may take place primarily at the periphery. Tendon injuries and recurrence of injuries are common in both humans and animals in sports. It is unclear why some areas of the tendon are more susceptible to such injuries and whether this is due to intrinsic regional differences in extracellular matrix (ECM) production or tissue turnover. This study aimed to compare populations of tenocytes derived from the tendon c...
Paterson YZ, Evans N, Kan S, Cribbs A, Henson FMD, Guest DJ.The transcription factor scleraxis (SCX) is expressed throughout tendon development and plays a key role in directing tendon wound healing. However, little is known regarding its role in fetal or young postnatal tendons, stages in development that are known for their enhanced regenerative capabilities. Here we used RNA-sequencing to compare the transcriptome of adult and fetal tenocytes following SCX knockdown. SCX knockdown had a larger effect on gene expression in fetal tenocytes, affecting 477 genes in comparison to the 183 genes affected in adult tenocytes, indicating that scleraxis-depend...
Journal of proteomicsAugust 5, 2020
Volume 228 103927 doi: 10.1016/j.jprot.2020.103927
Chiaradia E, Pepe M, Sassi P, Mohren R, Orvietani PL, Paolantoni M, Tognoloni A, Sforna M, Eveque M, Tombolesi N, Cillero-Pastor B.Osteochondrosis is a developmental orthopedic disease affecting growing cartilage in young horses. In this study we compared the proteomes of equine chondrocytes obtained from healthy and osteochondrotic cartilage using a label-free mass spectrometry approach. Quantitative changes of some proteins selected for their involvement in different functional pathways highlighted by the bioinformatics analysis, were validated by western blotting, while biochemical alterations of extracellular matrix were confirmed via Raman spectroscopy analysis. In total 1637 proteins were identified, of which 59 wer...
Marr N, Hopkinson M, Hibbert AP, Pitsillides AA, Thorpe CT.Three-dimensional imaging modalities for optically dense connective tissues such as tendons are limited and typically have a single imaging methodological endpoint. Here, we have developed a bimodal procedure utilising fluorescence-based confocal microscopy and x-ray micro-computed tomography for the imaging of adult tendons to visualise and analyse extracellular sub-structure and cellular composition in small and large animal species. Results: Using fluorescent immunolabelling and optical clearing, we visualised the expression of the novel cross-species marker of tendon basement membrane, lam...
Jeremiasse B, Matta C, Fellows CR, Boocock DJ, Smith JR, Liddell S, Lafeber F, van Spil WE, Mobasheri A.Chondrocytes are exposed to an inflammatory micro-environment in the extracellular matrix (ECM) of articular cartilage in joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). In OA, degenerative changes and low-grade inflammation within the joint transform the behaviour and metabolism of chondrocytes, disturb the balance between ECM synthesis and degradation, and alter the osmolality and ionic composition of the micro-environment. We hypothesize that chondrocytes adjust their physiology to the inflammatory microenvironment by modulating the expression of cell surface prote...
Changoor A, Garon M, Quenneville E, Bull SB, Gordon K, Savard P, Buschmann MD, Hurtig MB.We aimed to demonstrate that electroarthrography (EAG) measures streaming potentials originating in the cartilage extracellular matrix during load bearing through electrodes adhered to skin surrounding an articular joint. Equine metacarpophalangeal joints were subjected to simulated physiological loads while (1) replacing synovial fluid with immersion buffers of different electrolyte concentrations and (2) directly degrading cartilage with trypsin. An inverse relationship between ionic strength and EAG coefficient was detected. Compared to native synovial fluid, EAG coefficients increased ( &l...
Amaral A, Fernandes C, Rebordão MR, Szóstek-Mioduchowska A, Lukasik K, Gawronska-Kozak B, Telo da Gama L, Skarzynski DJ, Ferreira-Dias G.Neutrophil extracellular traps (NETs) fight endometritis, and elastase (ELA), a protease found in NETs, might induce collagen type I (COL1) accumulation in equine endometrium. Metallopeptidases (MMPs) are involved in extracellular matrix balance. The aim was to evaluate the effects of ELA and sivelestat (selective elastase inhibitor) on MMP-2 and MMP-9 expression and gelatinolytic activity, as well as the potential inhibitory effect of sivelestat on ELA-induced COL1 in equine endometrium. Endometrial explants from follicular (FP) and mid-luteal (MLP) phases were treated for 24 or 48 h with ELA...
Szóstek-Mioduchowska AZ, Baclawska A, Rebordão MR, Ferreira-Dias G, Skarzynski DJ.An increasing number of studies have shown that prostaglandins (PGs) exert multiple regulatory actions in the processes associated to tissue remodeling and fibrosis. Extracellular matrix (ECM) turnover is mediated by matrix metallopeptidases (MMPs). The knowledge about the regulation of their expression in mare endometrium is still limited. Thus, the aim of this study was to investigate whether: (i) profibrotic transforming growth factor (TGF)-β1 modulates PG production in equine endometrium; and (ii) PGE and PGF modulate MMPs, their tissue inhibitors (TIMPs), and collagen 1 (COL1) expression...
Atkinson F, Evans R, Guest JE, Bavin EP, Cacador D, Holland C, Guest DJ.Tendon injuries are a common cause of morbidity in humans. They also occur frequently in horses, and the horse provides a relevant, large animal model in which to test novel therapies. To develop novel cell therapies that can aid tendon regeneration and reduce subsequent reinjury rates, the mechanisms that control tendon tissue regeneration and matrix remodelling need to be better understood. Although a range of chemical cues have been explored (growth factors, media etc.), the influence of the mechanical environment on tendon cell culture has yet to be fully elucidated. To mimic the in vivo e...
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...
Szóstek-Mioduchowska A, Słowińska M, Pacewicz J, Skarzynski DJ, Okuda K.Equine endometrial fibrosis (endometrosis) is described as a degenerative chronic condition in the uterus. Its characteristic feature is excessive deposition of extracellular matrix (ECM) components around the endometrial glands and stroma. Although matrix metallopeptidases (MMPs) that mediate ECM turnover are important factors in the process of fibrosis, knowledge of their expression and regulation in endometrosis is limited. In other species, one of the important regulators of MMPs and tissue inhibitors of MMPs (TIMPs) is transforming growth factor (TGF)-β1. The goal of this study was to de...
Pinto-Cardoso R, Pereira-Costa F, Pedro Faria J, Bandarrinha P, Bessa-Andrês C, Correia-de-Sá P, Bernardo Noronha-Matos J.Chondrocytes and their mesenchymal cell progenitors secrete a variety of bioactive molecules, including adenine nucleotides and nucleosides, but these molecules are not usually highlighted in review papers about the secretome of these cells. Ageing and inflammatory insults compromise chondrocytes ability to keep ATP/adenosine synthesis, release and turnover. Cartilage homeostasis depends on extracellular adenosine levels, which acting via four P1 purinoceptor subtypes modulates the release of pro-inflammatory mediators, including NO, PGE and several cytokines. Native articular cartilage is cha...
Chiaradia E, Pepe M, Orvietani PL, Renzone G, Magini A, Sforna M, Emiliani C, Di Meo A, Scaloni A.Osteochondrosis is a failure of the endochondral ossification that affects developing joints in humans and several animal species. It is a localized idiopathic joint disorder characterized by focal chondronecrosis and growing cartilage retention, which can lead to the formation of fissures, subchondral bone cysts, or intra-articular fragments. Osteochondrosis is a complex multifactorial disease associated with extracellular matrix alterations and failure in chondrocyte differentiation, mainly due to genetic, biochemical, and nutritional factors, as well as traumas. This study describes the mai...
Roth SP, Brehm W, Groß C, Scheibe P, Schubert S, Burk J.Transforming growth factor beta 3 (TGFβ3) promotes tenogenic differentiation and may enhance tendon regeneration in vivo. This study aimed to apply TGFβ3 absorbed in decellularized equine superficial digital flexor tendon scaffolds, and to investigate the bioactivity of scaffold-associated TGFβ3 in an in vitro model. TGFβ3 could effectively be loaded onto tendon scaffolds so that at least 88% of the applied TGFβ3 were not detected in the rinsing fluid of the TGFβ3-loaded scaffolds. Equine adipose tissue-derived multipotent mesenchymal stromal cells (MSC) were then seeded on scaffolds loa...
Grzanna MW, Au RY, Au AY, Rashmir AM, Frondoza CG.Tendinopathy, a common disorder in man and horses, is characterized by pain, dysfunction, and tendon degeneration. Inflammation plays a key role in the pathogenesis of tendinopathy. Tendon cells produce proinflammatory molecules that induce pain and tissue deterioration. Currently used nonsteroidal anti-inflammatory drugs are palliative but have been associated with adverse side effects prompting the search for safe, alternative compounds. This study determined whether tendon-derived cells' expression of proinflammatory cyclooxygenase (COX)-2 and production of prostaglandin E2 (PGE) could be a...
Yang Q, Lopez MJ.The equine hoof dermal-epidermal interface requires progenitor cells with distinct characteristics. This study was designed to provide accurate ultrastructural depictions of progenitor cells isolated from inflamed tissue and normal tissue before and after cryopreservation and following selection of cells expressing both keratin (K) 14 (ectodermal) and cluster of differentiation (CD) 105 (mesodermal). Passage 3 cell ultrastructure was assessed following 2D culture and after 3D culture on decellularized hoof tissue scaffolds. Outcome measures included light, transmission electron, and scanning e...
Yang Q, Pinto VMR, Duan W, Paxton EE, Dessauer JH, Ryan W, Lopez MJ.Damage to an ectodermal-mesodermal interface like that in the equine hoof and human finger nail bed can permanently alter tissue structure and associated function. The purpose of this study was to establish and validate culture of primary progenitor cell isolates from the ectodermal-mesodermal tissue junction in equine hooves, the stratum internum, with and without chronic inflammation known to contribute to lifelong tissue defects. The following were evaluated in hoof stratum internum cell isolates up to 5 cell passages (P): expansion capacity by cell doublings and doubling time; plasticity ...
Inui T, Haneda S, Sasaki M, Furuoka H, Ito M, Yanagawa M, Hiyama M, Tabata Y, Sasaki N.In human cartilage tissue engineering, three-dimensional zirconia substrata have the potential advantage of producing many uniform cell clusters of controlled size without xenobiotic material, allowing easy clinical application. The objective of this study was to evaluate the possibility of using zirconia porous three-dimensional microwell substrata for chondrogenic differentiation of equine bone marrow-derived mesenchymal stem cells (BMMSCs) in vitro. In regular medium, 8 × 10, 2 × 10, and 5 × 10 equine BMMSCs from five thoroughbred horses were cultured on zirconia microwell su...
Szóstek-Mioduchowska AZ, Baclawska A, Okuda K, Skarzynski DJ.Equine endometrosis (endometrial fibrosis) is a degenerative chronic process that occurs in the uterus of the mare and disturbs proper endometrial function. Fibrosis is attributed to excessive deposition of extracellular matrix (ECM) components. The turnover of ECM is mediated by matrix metallopeptidases (MMP). Previously, it was shown that cytokines modulate MMP expression in other tissues and may regulate fibrosis indirectly by attracting inflammatory cells to the site of inflammation and directly on various tissues. However, the regulation of MMP expression in equine endometrosis is still r...
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...
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...
Desantis S, Accogli G, Albrizio M, Rossi R, Cremonesi F, Lange Consiglio A.Equine amniotic mesenchymal cells (eAMCs) are involved in many mechanisms in tissue regenerative processes. Their secreted vesicles are important effectors in a wide array of biological processes, and contribute to in vivo healing of equine tendon lesions and endometrial inflammation. Glycoconjugates are involved in cellular recognition and in the efficient uptake of extracellular vesicles (EVs) by recipient cells. In this study, we evaluated the surface glycosylation pattern of eAMCs and their EVs from the eAMCs released in conditioned medium. We used a microarray procedure in which eAMCs and...
Choi RK, Smith MM, Martin JH, Clarke JL, Dart AJ, Little CB, Clarke EC.Both mechanical and structural properties of tendon change after injury however the causal relationship between these properties is presently unclear. This study aimed to determine the extent of biomechanical change in post-injury tendon pathology and whether the sulphated glycosaminoglycans (glycosaminoglycans) present are a causal factor in these changes. Equine superficial digital flexor tendons (SDF tendons) were surgically-injured in vivo (n=6 injured, n=6 control). Six weeks later they were harvested and regionally dissected into twelve regions around the lesion (equal medial/lateral, pr...
Roth SP, Erbe I, Burk J.Reliable decellularization techniques applicable to tendon tissue play a critical role in the field of current tissue engineering. Particularly, an application as three-dimensional culture model for in vitro research and translational approaches to establish graft-based tendon repair as a routine clinical tool represent two main application fields for decellularized tendon scaffolds. Considering methodological issues of tendon decellularization, one of the major challenges lies in the preservation of the tendon-specific extracellular matrix (ECM) architecture to reflect natural tissue characte...
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...
Melzer M, Schubert S, Müller SF, Geyer J, Hagen A, Niebert S, Burk J.Mesenchymal stromal cells (MSC) represent a promising therapeutic tool for tendon regeneration. Their tenogenic differentiation is crucial for tissue engineering approaches and may support their beneficial effects after cell transplantation . The transforming growth factor (TGF)-, signalling via intracellular Smad molecules, is a potent paracrine mediator of tenogenic induction. Moreover, scaffold topography or tendon matrix components induced tenogenesis via activation of the Rho/ROCK cascade, which, however, is also involved in pathological adaptations in extracellular matrix pathologies. Th...
Thomas CM, Murray R, Sharif M.The purpose of this study was to investigate associations between the extent of chondrocyte apoptosis and expression of the articular cartilage (AC) extracellular matrix (ECM) molecules, cartilage oligomeric matrix protein (COMP) and fibronectin. Methods: Cartilage from four sites (when available) on equine left middle carpal joints (n = 12) were used. Expression of COMP and fibronectin was determined using specific polyclonal antibodies and a biotin-streptavidin/peroxidase method. The intensity of staining for matrix molecules was graded (none, mild, moderate, strong) in each cartilage zone. ...
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...
Peffers MJ, Thornton DJ, Clegg PD.Osteoarthritis is characterized by a loss of extracellular matrix that leads to cartilage degradation and joint space narrowing. Specific proteases, including the aggrecanases ADAMTS-4 and matrix metalloproteinase 3, are important in initiating and promoting cartilage degradation in osteoarthritis. This study investigated protease-specific and disease-specific cleavage patterns of particular extracellular matrix proteins by comparing new peptide fragments, neopeptides, in specific exogenous protease-driven digestion of a crude cartilage proteoglycan extract and an in-vitro model of early osteo...
Amaral A, Fernandes C, Rebordão MR, Szóstek-Mioduchowska A, Lukasik K, Gawronska-Kozak B, Telo da Gama L, Skarzynski DJ, Ferreira-Dias G.Neutrophil extracellular traps (NETs) fight endometritis, and elastase (ELA), a protease found in NETs, might induce collagen type I (COL1) accumulation in equine endometrium. Metallopeptidases (MMPs) are involved in extracellular matrix balance. The aim was to evaluate the effects of ELA and sivelestat (selective elastase inhibitor) on MMP-2 and MMP-9 expression and gelatinolytic activity, as well as the potential inhibitory effect of sivelestat on ELA-induced COL1 in equine endometrium. Endometrial explants from follicular (FP) and mid-luteal (MLP) phases were treated for 24 or 48 h with ELA...
Boeer U, Buettner FF, Klingenberg M, Antonopoulos GC, Meyer H, Haverich A, Wilhelmi M.The limited biocompatibility of decellularized scaffolds is an ongoing challenge in tissue engineering. Here, we demonstrate the residual immunogenicity of an extensively decellularized equine carotid artery (dEAC(intens)) and identify the involved immunogenic components. EAC were submitted to an elaborated intensified decellularization protocol with SDS/sodium desoxycholate for 72 h using increased processing volumes (dEAC(intens)), and compared to dEAC(ord) prepared by an ordinary protocol (40 h, normal volumes). Matrix integrity was checked via correlative volumetric visualization which rev...
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...
Saljic A, Friederike Fenner M, Winters J, Flethøj M, Eggert Eggertsen C, Carstensen H, Dalgas Nissen S, Melis Hesselkilde E, van Hunnik A....Fibroblasts maintain the extracellular matrix homeostasis and may couple to cardiomyocytes through gap junctions and thereby increase the susceptibility to slow conduction and cardiac arrhythmias, such as atrial fibrillation (AF). In this study, we used an equine model of persistent AF to characterize structural changes and the role of fibroblasts in the development of an arrhythmogenic substrate for AF. Methods: Eleven horses were subjected to atrial tachypacing until self-sustained AF developed and were kept in AF for six weeks. Horses in sinus rhythm (SR) served as control. In terminal open...
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,...
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 â...
Svala E, Löfgren M, Sihlbom C, Rüetschi U, Lindahl A, Ekman S, Skiöldebrand E.The molecular aspects of inflammation were investigated in equine articular cartilage explants using quantitative proteomics. Articular cartilage explants were stimulated with interleukin (IL)-1β in vitro for 25 days, and proteins released into cell culture media were chemically labeled with isobaric mass tags and analyzed by liquid chromatography-tandem mass spectrometry. A total of 127 proteins were identified and quantified in media from explants. IL-1β-stimulation resulted in an abundance of proteins related to inflammation, including matrix metalloproteinases, acute phase proteins, comp...
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...
Löfgren M, Svala E, Lindahl A, Skiöldebrand E, Ekman S.Osteoarthritis is an inflammatory and degenerative joint disease commonly affecting horses. To identify genes of relevance for cartilage pathology in osteoarthritis we studied the time-course effects of interleukin (IL)-1β on equine articular cartilage. Articular cartilage explants from the distal third metacarpal bone were collected postmortem from three horses without evidence of joint disease. The explants were stimulated with IL-1β for 27 days and global gene expression was measured by microarray. Gene expression was compared to that of unstimulated explants at days 3, 9, 15, 21 and 27...
Carlson ER, Stewart AA, Carlson KL, Durgam SS, Pondenis HC.To compare the effects of autologous equine serum (AES) and autologous conditioned serum (ACS) on equine articular chondrocyte metabolism when stimulated with recombinant human (rh) interleukin (IL)-1β. Methods: Articular cartilage and nonconditioned and conditioned serum from 6 young adult horses. Methods: Cartilage samples were digested, and chondrocytes were isolated and formed into pellets. Chondrocyte pellets were treated with each of the following: 10% AES, 10% AES and rhIL-1β, 20% AES and rhIL-1β, 10% ACS and rhIL-1β, and 20% ACS and rhIL-1β, and various effects of these treatments...
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...
van Weeren PR, Firth EC, Brommer H, Hyttinen MM, Helminen AE, Rogers CW, Degroot J, Brama PA.Training at a very young age may influence the characteristics of the collagen network of articular cartilage extracellular matrix (ECM) in horses. Objective: To investigate whether increasing workload of foals results in significant changes in the biochemical composition of articular cartilage ECM. Methods: Thoroughbred foals (n = 33) were divided into 2 different exercise groups from age 10 days-18 months. One group (PASTEX; n = 15) was reared at pasture; the other (CONDEX; n = 18) underwent a specific additional training programme that increased workload by 30%. At mean age 18 months, 6 ani...
Zanotto GM, Liesbeny P, Barrett M, Zlotnick H, Frank E, Grodzinsky AJ, Frisbie DD.Microfracture augmentation can be a cost-effective single-step alternative to current cartilage repair techniques. Trypsin pretreatment combined with a growth factor-functionalized self-assembling KLD hydrogel ("functionalized hydrogel") has been shown to improve overall cartilage repair and integration to surrounding tissue in small animal models of osteochondral defects. Microfracture combined with trypsin treatment and a functionalized hydrogel will improve reparative tissue quality and integration as compared with microfracture alone in an equine model. Controlled laboratory study. Bilater...
Walter I, Handler J, Miller I, Aurich C.Periglandular arrangement of myofibroblasts, associated with the deposition of extracellular matrix (ECM), is a cardinal feature of endometrosis in mares. We hypothesized that a disturbance in the expression of matrix degrading enzymes such as matrix metalloproteinases (MMP's) and matrix cross-linking proteins might lead to an imbalance in deposition and degradation of extracellular matrix components and thereby accentuate degeneration. Therefore, distributions of MMP-2, capable of collagen IV and laminin degradation, and tissue transglutaminase (TG2), a cross-linker of extracellular matrix pr...
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...
Johnson A, Smith R, Saxne T, Hickery M, Heinegård D.Previous experiments have shown that addition of fragmented fibronectin can induce cartilage chondrolysis. In this study we investigated the fate of the collagen- and cell-binding molecules Cartilage oligomeric matrix protein (COMP) and chondroadherin. Methods: Equine articular cartilage explants were stimulated with the C-terminal and the N-terminal heparin-binding fragments of fibronectin respectively, and the conditioned media were analysed by both quantitative (ELISA) and qualitative (mass spectrometry, Western blots) methods. Results: Both COMP and chondroadherin were released in a dose-d...
Marr N, Hopkinson M, Hibbert AP, Pitsillides AA, Thorpe CT.Three-dimensional imaging modalities for optically dense connective tissues such as tendons are limited and typically have a single imaging methodological endpoint. Here, we have developed a bimodal procedure utilising fluorescence-based confocal microscopy and x-ray micro-computed tomography for the imaging of adult tendons to visualise and analyse extracellular sub-structure and cellular composition in small and large animal species. Results: Using fluorescent immunolabelling and optical clearing, we visualised the expression of the novel cross-species marker of tendon basement membrane, lam...
Harman RM, Bihun IV, Van de Walle GR.The prevalence of cutaneous fibroproliferative disorders (CFPDs) is high and almost exclusively occurs in humans (keloids and hypertrophic scars) and horses (exuberant granulation tissue), making the horse a valuable translational model for studies on prevention and treatment of human CFPDs. CFPDs arise as a result of dysregulated wound healing characterized by persistently high levels of cytokines, such as transforming growth factor beta 1 (TGF-β1), that contribute to excessive extracellular matrix deposition, and the physical disorganization of dermal fibroblasts (DF). The mesenchymal strom...
Williams ZJ, Velez-Irizarry D, Gardner K, Valberg SJ.Myofibrillar myopathy in humans causes protein aggregation, degeneration, and weakness of skeletal muscle. In horses, myofibrillar myopathy is a late-onset disease of unknown origin characterized by poor performance, atrophy, myofibrillar disarray, and desmin aggregation in skeletal muscle. This study evaluated molecular and ultrastructural signatures of myofibrillar myopathy in Warmblood horses through gluteal muscle tandem-mass-tag quantitative proteomics (5 affected, 4 control), mRNA-sequencing (8 affected, 8 control), amalgamated gene ontology analyses, and immunofluorescent and electron m...
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...
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...
Busschers E, Holt JP, Richardson DW.To determine effects of interleukin (IL)-1 beta and glucocorticoids on total glycosaminoglycan (GAG) loss and aggrecanase-mediated matrix degradation in equine cartilage. Methods: Cartilage from 24 equine cadavers free of sepsis and musculoskeletal disease. Methods: Effects of IL-1 beta, IL-1 beta with glucocorticoids (dexamethasone and triamcinolone, 10(-6) and 10(-7)M), and glucocorticoids alone on degradation of equine articular and nasal cartilage explants were assessed by measuring GAG release in media and GAG content in cartilage. Aggrecanase-mediated cleavage within the interglobular do...