Collagen is a structural protein found abundantly in the connective tissues of horses, including skin, tendons, ligaments, and cartilage. It contributes to the strength and elasticity of these tissues, playing a significant role in maintaining structural integrity. Collagen fibers are composed of amino acid chains, primarily glycine, proline, and hydroxyproline, which form a triple helix structure. In horses, collagen is involved in various physiological processes, including tissue repair and regeneration. Changes in collagen composition and structure can be associated with conditions such as joint disorders and tendon injuries. This page compiles peer-reviewed research studies and scholarly articles that explore the synthesis, function, and clinical implications of collagen in equine health.
Rosa MCB, Campos MEST, Albuquerque AS, Braz MS, Mapele RO, de Oliveira MCG, Toma HS, Ferraz PFP, Pereira RN, Raymundo DL.Skin wounds in horses, particularly in the distal extremities, often heal slowly due to mechanical stress, compromised perfusion, and excessive fibroplasia. This study evaluated the effects of topical Croton lechleri (CL) cream, alone or in combination with nitroglycerin, on the healing of skin wounds in the metatarsal region of horses. Six mares received six standardized wounds in each region and were treated with: saline solution, nitroglycerin (0.1 or 1 mg/mL), CL (1 or 10 µg/mL), or CL + nitroglycerin (10 µg/mL + 1 mg/mL). Wound contraction, histology, and bacterial culture were evaluate...
Partusch L, Rutland CS, Martens A, Du Cheyne C, De Spiegelaere W, Michler JK.Exuberant granulation tissue (EGT) is a second intention wound healing disorder. It commonly occurs in the distal limb of horses. EGT causes significant increase in the duration and cost of treatment, potentially leading to the decision not to pursue treatment and euthanize the patient. The underlying pathomechanisms of this fibroproliferative disorder remain unclear, particularly in terms of collagen composition and the association between myofibroblasts and blood vessels. This study investigated the collagen composition in naturally occurring EGT following trimming in 19 horses (EGT group). ...
Kranenburg LC, Reinke KS, van den Broek J, Zaal EA, van den Boom R, van Doorn DA.Hydrolysed collagen is used as a supplement for horses with osteoarthritis, hoof horn growth problems, and gastric ulcers. To determine the oral availability of a specific hydrolysed collagen supplement and the appropriate dose, six Warmblood mares were fed two different concentrations of the supplement: 100 g HC (C), 50 g HC (C), and a control of 0 g HC (C) during one week in a randomised cross-over design. On day 7, 14 and 21, blood sampling for amino acid (AA) analysis was performed, just prior to feeding the supplement (t = 0) and every hour after feeding for 8 h (t = 1-8). Statistical ana...
Samol MA, Barrett MF, Frisbie DD.Significant distal interphalangeal joint (DIPJ) pathology, particularly affecting soft tissue and articular cartilage, is often not identifiable on radiographs but can be accompanied by joint capsule enthesopathy on the middle phalanx (P2), which can be readily identified. Objective: To explore frequency and correlations between DIPJ capsule enthesopathy identified on magnetic resonance imaging (MRI) and radiographs and DIPJ articular cartilage abnormalities and other concurrent soft tissue or osseous pathology within the foot found on MRI. Methods: Retrospective descriptive case series. Metho...
Böck MJ, Fernandez TJ, Pereira VP, da Veiga ML, de Mello Bertoncheli Dos Santos C, de Morais-Pinto L.We examined 52 horse aortas to characterize the morphological aspects of the aortic bulb wall and the ascending aorta. The morphometric data were analyzed using ImageJ®-Fiji 1.5 software. The Tunica intima was composed of endotheliocytes with scarce cytoplasm and ellipsoid nuclei, supported by a collagenous subendothelial stratum. The Tunica media was composed entirely of fascicles of vascular smooth muscle cells interspersed with bundles of collagen fibers and elastic lamellae, characterizing the aortic medial lamellar unit. The Tunica adventitia consisted of two distinct sub-layers: the ext...
Durgam S.The mid-metacarpal SDFT, intrasynovial DDFT and suspensory ligament are frequently injured soft tissues in the equine athlete. The mid-metacarpal SDFT exhibits a hierarchical structure and encounters repetitive strains at its functional limit. The intrasynovial DDFT possesses fibrocartilage where opposing bony surfaces to facilitate resistance-free gliding and contains chondrocyte-like cells embedded in a proteoglycan-rich ECM. While suspensory ligament enthesis injuries are common, collagen and non-collagen ECM structure-function specializations at the bone-ligament interface are understudied...
Koch DW.Our understanding of tendon homeostasis and repair following injury has made great strides through basic science, clinical veterinary medicine, and preclinical translational research. We have now gleaned a greater understanding of the cellular and matrix dynamics that are being orchestrated within the tendon, which provide therapeutic opportunities. This article will focus on how utilizing the horse and equine tissues have advanced our understanding of tendinopathy and the cellular and matrix dynamics at play while also identifying continued gaps in our knowledge where the horse as a veterinar...
Clarke EJ, Jensen A, Gillen AM, Bardell D, Senior M, Anderson JR, Peffers MJ.To determine the protein composition of equine platelet-rich plasma (PRP) and PRP-derived extracellular vesicles (EVs) and evaluate their effects on tendon inflammation in vitro. As tendon injuries are common in horses and treatment with PRP derived from the horse's own blood shows promise, but outcomes vary due to inconsistent composition. PRP contains EVs that facilitate cell communication. Unassigned: From December 2022 through May 2023, equine plasma (n = 3, adult) was isolated via double centrifugation and PRP produced using a commercial kit. Extracellular vesicles were isolated using dif...
Santiviparat S, Suthithanakom S, Bhanpattanakul S, Srisuwattanasagul S, Melde K, Stout TAE, Tharasanit T.Advances in endometrial tissue engineering have enabled the combination of modified scaffolding materials with modern cell culture technologies. Genipin and three-dimensional (3D) printing have advanced cell-tissue engineering by enabling the precise layering of cell-containing matrices while ensuring low cytotoxicity. This study aimed to advance equine endometrial tissue engineering by designing customized collagen scaffolds using 3D printing technology, while optimizing the genipin concentration to avoid toxicity. Genipin was tested at concentrations of 4, 2, 1, 0.5, 0.25, 0.125, and 0 mM on...
Marine L, Wilfried P, Joëlle P, Justine J, Axel D, Vinciane T, Benoît V, Laurent G, Luc G, Jean-François K, Nadine A.In situ injection of mesenchymal stem cells appears as a promising treatment of tendinopathies. Tendon-derived mesenchymal stem cells (TDSCs) are widely studied and show a lot of interesting characteristics for clinical use. The aim of this study is to confirm the tenogenic potential of cryopreserved TDSCs and to confirm their ability to produce type I and/or type III collagens fibers in culture. Tendon-derived mesenchymal stem cells are harvested from the tendon no later than 72 h post-mortem. Their tenogenic potential has been assessed by quantitative reverse transcriptase polymerase chain ...
Martinez-Saez L, Marín-García PJ, Llobat ML.Osteochondrosis (OC) is a frequent manifestation of developmental orthopaedic disease, and its severe clinical presentation is known as OC dissecans (OCD). OC is defined as a disruption of the endochondral ossification process in the epiphyseal cartilage, and this disease has been reported in different mammalian species, including humans, dogs, pigs, and horses. OCD is an important cause of lameness in sport horses and is a common cause of impaired orthopaedic potential, whose clinical signs may be of minimal magnitude or manifest as severe joint effusion or clinically noticeable lameness. The...
Pawlina-Tyszko K, Semik-Gurgul E, Podstawski P, Herc W, Witkowski M, Ropka-Molik K.Alterations in the genes involved in the creation of the extracellular matrix (ECM) were observed in our earlier transcriptome studies of sarcoids and their cell culture model. For a complete characterization of the underlying molecular pathways, it is imperative to comprehend the involvement of ECM modifications in the oncogenic transformation of sarcoid fibroblasts. Thus, the aim of this investigation was to describe the expression patterns of a set of genes that are essential for the rearrangements of the extracellular matrix, namely collagen genes, and elucidate possible mechanisms underly...
Carmona JU, López C.(1) Background: Tendon and ligament injuries are a leading cause of lameness in horses, with significant economic implications. Platelet-rich plasma (PRP) has gained attention for its regenerative potential, but its efficacy remains uncertain due to inconsistent study designs and reporting. (2) Methods: This systematic review, following the PRISMA guidelines, evaluated 22 studies (clinical and experimental) to assess the safety and efficacy of PRP in treating equine tendon and ligament injuries. The risk of bias was analyzed using the ROBINS-I and RoB 2.0 tools. (3) Results: PRP demonstrated a...
Ishikawa Y, Tufa SF, Keene DR, Bächinger HP, Winand NJ.Mutations in the collagen-modifying enzyme lysyl hydroxylase 1 (LH1) cause Warmblood Fragile Foal Syndrome (WFFS) in horses. We investigated the impact of this mutation on collagen structure and function. Our results show that LH1 deficiency leads to reduced lysine hydroxylation, altered collagen fibril organization, and tissue abnormalities resembling human Ehlers-Danlos syndrome. These findings highlight the critical role of LH1 in collagen biosynthesis and provide insights into the pathogenesis of WFFS.
Ana A, Agnieszka S, Marta CP, Pawel K, Dariusz S, Graça FD, Szóstek-Mioduchowska A.Equine endometrosis is a major cause of infertility in mares and is characterized by degenerative, functional and fibrotic changes in the endometrium with increased collagen (COL) deposition. Transforming growth factor (TGF)-β1 is one of the major pro-fibrotic factors involved in the excessive deposition of extracellular matrix (ECM) components in the equine endometrium. It has been demonstrated that ovarian steroids, specifically 17β-estradiol (E2) and progesterone (P4), not only regulate the cyclicity of the estrous cycle, but also have been implicated as anti- or pro-fibrotic factors. Thi...
Wu J, Na H, Bai F, Li S, Gao H, Sha R.Horse bone is rich in collagen, with a composition similar to that of human collagen. Collagen peptides supply nutrients needed for human growth that act as antioxidants, lower blood pressure. This study explored the extraction of collagen and the preparation of collagen short peptides from Mongolian horse bones. Bones were collected from horses of varying ages, and the collagen content along with calcium salt distribution were observed through staining and imaging analyses. Next, the bones were processed into a powder and then subjected to ultra-high-pressure processing for degreasing. The de...
Cerveira-Pinto M, Wójtowicz A, Pires MA, Kordowitzki P, Skarzynski D, Ferreira-Dias G, Szóstek-Mioduchowska A, Amaral A.Increased synthesis and deposition of collagen (COL) in the extracellular matrix (ECM) of equine endometrium contributes to endometrosis. Toll-like receptors (TLRs) are transmembrane receptors involved in the innate immune response, recognized for their role in antigen recognition and previously associated with equine endometritis. The TLRs not only recognize pathogen-associated molecular patterns but also regulate inflammations, fibrosis and cancer. The aim of this study was to explore the relationship between TLR expression at different stages of Kenney and Doig's (K-D) grading and COL1 exp...
Correa-Piña BA, Castillo-Paz AM, Davila U, Rodriguez-Garcia ME.The aim of this work is to investigate the changes in the physicochemical properties of hydroxyapatite (HAp) extracted from horse humerus bones of different ages (1, 3, 6, and 8 years) subjected to low temperature calcination (600°C). Thermal analysis revealed significant mass loss due to water, collagen, organic compounds, carbonates, and age-related magnesium out-diffusion. Higher fat content in older bones contributed to increased mass loss. Phosphorus content remained constant across age groups, while calcium and sodium showed age-related fluctuations. Magnesium levels decreased with ag...
Centeno LAM, Bastos HBA, Bueno VLC, Trentin JM, Fiorenza M, Panziera W, Winter GHZ, Kretzmann NA, Fiala-Rechsteiner S, Mattos RC, Rubin MIB.Equine endometrosis is a degenerative and predominantly fibrotic condition resulting from progressive and irreversible multifactorial causes that influence the endometrium of mare. Tissue remodeling in the equine endometrium occurs as part of the pathogenesis of endometrosis, a process characterized by a shift in extracellular matrix (ECM) components. The relationship between matrix metalloproteinases and their specific inhibitors is crucial for the remodeling process. Collagen play a significant role in maintaining a healthy uterus and may promote fibrotic processes. The aim of this study was...
Damone J, Bass L, Gadomski B, Rao S, Frank C, Moorman VJ.The equine digital cushion (DC) has been a poorly understood structure regarding its mechanical properties and composition. The objective of this study was to develop a sampling technique and to compare the biomechanical and histologic properties of DC between lame and non-lame forelimbs. Both forefeet from horses with induced carpal lameness were radiographed prior to humane euthanasia. Radiographs were used to guide sample collection of two, post-mortem, midline DC samples, palmar and dorsal, via an 8mm biopsy punch. Samples were subjected to compressive testing to determine elastic modulus....
Heidari N, Faragher RGA, Pattison G, Dudhia J, Smith RKW.Tendinopathy is a common age-related disease which causes significant morbidity for both human athletes and performance horses. In the latter, the superficial digital flexor tendon is an excellent model for human tendinopathies because it is a functional homologue of the human Achilles tendon and a primary site of injuries with strong similarities to the human disease. Corticosteroids have been previously used clinically to treat tendinopathic inflammation, but they upregulate the p53-p21 axis with concomitant reductions in cell proliferation and collagen synthesis in human tenocytes. This phe...
Rajabimashhadi Z, Gallo N, Russo F, Ghiyami S, Mele C, Giordano ME, Lionetto MG, Salvatore L, Lionetto F.In recent years, significant academic and commercial interest has focused on collagen derived from horse tendons, with potential applications across diverse sectors such as medicine, pharmaceuticals, and cosmetics. Nano collagen, with its enhanced wound penetration, improved cell contact, and heightened cellular regeneration and repair capabilities due to its high surface area, holds promise for a wide range of applications. In this study, we present a novel method for producing nano collagen from the equine tendon. Our approach is characterized by its speed, affordability, simplicity and envi...
Skedros JG, Dayton MR, Cronin JT, Mears CS, Bloebaum RD, Wang X, Bachus KN.Many bones experience bending, placing one side in net compression and the other in net tension. Because bone mechanical properties are relatively reduced in tension compared with compression, adaptations are needed to reduce fracture risk. Several toughening mechanisms exist in bone, yet little is known of the influences of secondary osteon collagen/lamellar 'morphotypes' and potential interplay with intermolecular collagen cross-links (CCLs) in prevalent/predominant tension- and compression-loaded regions. Paired third metacarpals (MC3s) from 10 adult horses were prepared for mechanical test...
Dubuc J, Schneider MJ, Dubuc V, Richard H, Pinsard M, Bancelin S, Legare F, Girard C, Laverty S.Investigate meniscal extracellular matrix degradation. Equine menisci ( = 34 from 17 horses) were studied. Site-matched sections were cut and scored from three regions (ROIs; = 102) and stained for histology, proteoglycan (safranin O and fast green), aggrecan, and collagen cleavage (NITEGE, DIPEN, and C1,2C antibodies, respectively). Picrosirius red and second harmonic generation microscopy were performed to investigate collagen ultrastructure. A total of 42 ROIs met the inclusion criteria and were included in the final analysis. The median (range) ROI histological score was 3 (0-9), providin...
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...
Santiviparat S, Swangchan-Uthai T, Stout TAE, Buranapraditkun S, Setthawong P, Taephatthanasagon T, Rodprasert W, Sawangmake C, Tharasanit T.To better understand molecular aspects of equine endometrial function, there is a need for advanced in vitro culture systems that more closely imitate the intricate 3-dimensional (3D) in vivo endometrial structure than current techniques. However, development of a 3D in vitro model of this complex tissue is challenging. This study aimed to develop an in vitro 3D endometrial tissue (3D-ET) with an epithelial cell phenotype optimized by treatment with a Rho-associated protein kinase (ROCK) inhibitor. Equine endometrial epithelial (eECs) and mesenchymal stromal (eMSCs) cells were isolated separat...
Gaesser AM, Usimaki AIJ, Barot DA, Linardi RL, Molugu S, Musante L, Ortved KF.Mesenchymal stem cell (MSC) extracellular vesicles (EVs) have emerged as a biotherapeutic for osteoarthritis; however, manufacturing large quantities is not practical using traditional monolayer (2-D) culture. We aimed to examine the effects of 3-D and 2-D culture 2 types of media: Dulbecco modified Eagle medium and a commercially available medium (CM) on EV yield. Methods: Banked bone marrow-derived MSCs (BM-MSCs) from 6 healthy, young horses were used. Methods: 4 microcarriers (collagen-coated polystyrene, uncoated polystyrene, collagen-coated dextran, and uncoated dextran) were tested in st...
Smith EJ, Beaumont RE, Dudhia J, Guest DJ.Tissue fibrosis following tendon injury is a major clinical problem due to the increased risk of re-injury and limited treatment options; however, its mechanism remains unclear. Evidence suggests that insufficient resolution of inflammation contributes to fibrotic healing by disrupting tenocyte activity, with the NF-κB pathway being identified as a potential mediator. Equine embryonic stem cell (ESC) derived tenocytes may offer a potential cell-based therapy to improve tendon regeneration, but how they respond to an inflammatory environment is largely unknown. Our findings reveal for the firs...
Miglio A, Falcinelli E, Cappelli K, Mecocci S, Mezzasoma AM, Antognoni MT, Gresele P.Training has a significant effect on the physiology of blood coagulation in humans and in horses. Several hemostatic changes have been reported after exercise in the horse but data available are inconclusive. The aim of this study was to investigate platelet activation and primary platelet-related hemostasis modifications in young never-trained Thoroughbreds in the first incremental training period in order to improve knowledge on this topic. Twenty-nine clinically healthy, untrained, 2-year-old Thoroughbred racehorses were followed during their incremental 4-month sprint exercise training. Bl...
Michotte M, Raes E, Oosterlinck M.The diagnostic value of plain radiography for diagnosing synovial penetration in limb wounds near synovial structures has not been determined. Objective: To assess diagnostic accuracy of plain radiography to identify synovial penetration in horses with traumatic limb wounds. Methods: Retrospective case study. Methods: Case records of horses presented to the Faculty of Veterinary Medicine of Ghent University (2011-2021) with limb wounds near synovial structures were categorised in groups with and without synovial penetration using results of synovial fluid analysis and surgical findings. Plain ...
Frisbie DD, Oxford JT, Southwood L, Trotter GW, Rodkey WG, Steadman JR, Goodnight JL, McIlwraith CW.The current study investigated healing of large full-thickness articular cartilage defects during the first 8 weeks with and without penetration of the subchondral bone using microfracture in an established equine model of cartilage healing. Chondral defects in the weightbearing portion of the medial femoral condyle were made bilaterally; one defect in each horse was microfractured whereas the contralateral leg served as the control. The expression of cartilage extracellular matrix components (Types I and II collagen and aggrecan) was evaluated using histologic techniques, reverse transcriptio...
Fortier LA, Mohammed HO, Lust G, Nixon AJ.Composites of chondrocytes and polymerised fibrin were supplemented with insulin-like growth factor-I (IGF-I) during the arthroscopic repair of full-thickness cartilage defects in a model of extensive loss of cartilage in horses. Repairs facilitated with IGF-I and chondrocyte-fibrin composites, or control defects treated with chondrocyte-fibrin composites alone, were compared before death by the clinical appearance and repeated analysis of synovial fluid, and at termination eight months after surgery by tissue morphology, collagen typing, and biochemical assays. The structure of cartilage was ...
Schnabel LV, Mohammed HO, Miller BJ, McDermott WG, Jacobson MS, Santangelo KS, Fortier LA.Platelet rich plasma (PRP) has recently been investigated for use in tissue regeneration studies that seek to utilize the numerous growth factors released from platelet alpha-granules. This study examined gene expression patterns, DNA, and collagen content of equine flexor digitorum superficialis tendon (SDFT) explants cultured in media consisting of PRP and other blood products. Blood and bone marrow aspirate (BMA) were collected from horses and processed to obtain plasma, PRP, and platelet poor plasma (PPP). IGF-I, TGF-beta1, and PDGF-BB were quantified in all blood products using ELISA. Ten...
Caliari SR, Harley BA.Current surgical and tissue engineering approaches for treating tendon injuries have shown limited success, suggesting the need for new biomaterial strategies. Here we describe the development of an anisotropic collagen-glycosaminoglycan (CG) scaffold and use of growth factor supplementation strategies to create a 3D platform for tendon tissue engineering. We fabricated cylindrical CG scaffolds with aligned tracks of ellipsoidal pores that mimic the native physiology of tendon by incorporating a directional solidification step into a conventional lyophilization strategy. By modifying the freez...
Schnabel LV, Lynch ME, van der Meulen MC, Yeager AE, Kornatowski MA, Nixon AJ.Tendinitis remains a catastrophic injury among athletes. Mesenchymal stem cells (MSCs) have recently been investigated for use in the treatment of tendinitis. Previous work has demonstrated the value of insulin-like growth factor-I (IGF-I) to stimulate cellular proliferation and tendon fiber deposition in the core lesion of tendinitis. This study examined the effects of MSCs, as well as IGF-I gene-enhanced MSCs (AdIGF-MSCs) on tendon healing in vivo. Collagenase-induced bilateral tendinitis lesions were created in equine flexor digitorum superficialis tendons (SDFT). Tendons were treated with ...
Wilke MM, Nydam DV, Nixon AJ.Mesenchymal stem cells (MSCs) provide an important source of pluripotent cells for musculoskeletal tissue repair. This study examined the impact of MSC implantation on cartilage healing characteristics in a large animal model. Twelve full-thickness 15-mm cartilage lesions in the femoropatellar articulations of six young mature horses were repaired by injection of a self-polymerizing autogenous fibrin vehicle containing mesenchymal stem cells, or autogenous fibrin alone in control joints. Arthroscopic second look and defect biopsy was obtained at 30 days, and all animals were euthanized 8 month...
Thorpe CT, Streeter I, Pinchbeck GL, Goodship AE, Clegg PD, Birch HL.Little is known about the rate at which protein turnover occurs in living tendon and whether the rate differs between tendons with different physiological roles. In this study, we have quantified the racemization of aspartic acid to calculate the age of the collagenous and non-collagenous components of the high strain injury-prone superficial digital flexor tendon (SDFT) and low strain rarely injured common digital extensor tendon (CDET) in a group of horses with a wide age range. In addition, the turnover of collagen was assessed indirectly by measuring the levels of collagen degradation mark...
Frisbie DD, Trotter GW, Powers BE, Rodkey WG, Steadman JR, Howard RD, Park RD, McIlwraith CW.To evaluate the effect of arthroscopic subchondral bone microfracture on healing of large chondral defects in horses. Methods: Short- (4 months) and long-term (12 months) in vivo experimental chondral defect model. Methods: 10 horses, aged 2 to 5 years. Methods: Each horse had a 1 cm2 full-thickness chondral defect created in both radial carpal bones and both medial femoral condyles. One carpus and one femoral condyle of each horse had the subchondral bone plate under the defect perforated using an orthopedic awl. All horses were exercised, five horses were evaluated after 4 months and five ho...
Angele P, Abke J, Kujat R, Faltermeier H, Schumann D, Nerlich M, Kinner B, Englert C, Ruszczak Z, Mehrl R, Mueller R.Collagen-based scaffolds are appealing products for the repair of cartilage defects using tissue engineering strategies. The present study investigated the species-related differences of collagen scaffolds with and without 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS)-crosslinking. Resistance against collagenase digestion, swelling ratio, amino acid sequence, shrinkage temperature, ultrastructural matrix morphology, crosslinking density and stress-strain characteristics were determined to evaluate the physico-chemical properties of equine- and bovine-collagen...
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...
Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL.To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. Methods: 8 horses. Methods: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were...
Frisbie DD, Al-Sobayil F, Billinghurst RC, Kawcak CE, McIlwraith CW.To discriminate between changes in biomarkers with exercise compared to changes in biomarkers with osteoarthritis (OA) in exercising horses. Methods: Sixteen, 2-year-old horses were randomly assigned either to an exercise-alone (n=8) or OA-affected (also exercised) (n=8) group. All horses had both mid-carpal joints arthroscoped and OA induced in one mid-carpal joint in the OA-affected joints of OA-affected horses. Two weeks after surgery all horses commenced a strenuous exercise program on a high-speed treadmill. Clinical outcomes and synovial fluid and serum biomarkers, were evaluated weekly....
Bosch G, van Schie HT, de Groot MW, Cadby JA, van de Lest CH, Barneveld A, van Weeren PR.Tendon injuries are notorious for their slow and functionally inferior healing. Intratendinous application of platelet-rich plasma (PRP) has been reported to stimulate the repair process of tendon injuries, but there is little conclusive evidence for its effectiveness. A placebo-controlled experimental trial was performed to test the hypothesis that a single intratendinous PRP treatment enhances the quality of tendon repair, as evidenced by improved biochemical, biomechanical, and histological tissue properties. In six horses, tendon lesions were created surgically in the Superficial Digital F...
Kisiday JD, Kopesky PW, Evans CH, Grodzinsky AJ, McIlwraith CW, Frisbie DD.Bone marrow mesenchymal stem cells (BM-MSCs) and adipose-derived progenitor cells (ADPCs) are potential alternatives to autologous chondrocytes for cartilage resurfacing strategies. In this study, the chondrogenic potentials of these cell types were compared by quantifying neo-tissue synthesis and assaying gene expression and accumulation of extracellular matrix (ECM) components of cartilage. Adult equine progenitor cells encapsulated in agarose or self-assembling peptide hydrogels were cultured in the presence or absence of TGFbeta1 for 3 weeks. In BM-MSCs-seeded hydrogels, TGFbeta1 stimulate...
Sivaguru M, Durgam S, Ambekar R, Luedtke D, Fried G, Stewart A, Toussaint KC.Fourier transform-second harmonic generation (FT-SHG) imaging is used as a technique for evaluating collagenase-induced injury in horse tendons. The differences in collagen fiber organization between normal and injured tendon are quantified. Results indicate that the organization of collagen fibers is regularly oriented in normal tendons and randomly organized in injured tendons. This is further supported through the use of additional metrics, in particular, the number of dark (no/minimal signal) and isotropic (no preferred fiber orientation) regions in the images, and the ratio of forward-to-...
Malda J, Benders KE, Klein TJ, de Grauw JC, Kik MJ, Hutmacher DW, Saris DB, van Weeren PR, Dhert WJ.Articular cartilage defects are common after joint injuries. When left untreated, the biomechanical protective function of cartilage is gradually lost, making the joint more susceptible to further damage, causing progressive loss of joint function and eventually osteoarthritis (OA). In the process of translating promising tissue-engineering cartilage repair approaches from bench to bedside, pre-clinical animal models including mice, rabbits, goats, and horses, are widely used. The equine species is becoming an increasingly popular model for the in vivo evaluation of regenerative orthopaedic ap...
Vidal MA, Robinson SO, Lopez MJ, Paulsen DB, Borkhsenious O, Johnson JR, Moore RM, Gimble JM.To compare the chondrogenic potential of adult equine mesenchymal stem cells derived from bone marrow (MSCs) or adipose tissue (ASCs). Methods: In vitro experimental study. Methods: Adult Thoroughbred horses (n=11). Methods: BM (5 horses; mean [+/-SD] age, 4+/-1.4 years) or adipose tissue (6 horses; mean age, 3.5+/-1.1 years) samples were obtained. Cryopreserved MSCs and ASCs were used for pellet cultures in stromal medium (C) or induced into chondrogenesis+/-transforming growth factor-3 (TGFbeta(3)) and bone morphogenic factor-6 (BMP-6). Pellets harvested after 3, 7, 14, and 21 days were exam...
Thorpe CT, Peffers MJ, Simpson D, Halliwell E, Screen HR, Clegg PD.Tendon is a simple aligned fibre composite, consisting of collagen-rich fascicles surrounded by a softer interfascicular matrix (IFM). The composition and interactions between these material phases are fundamental in ensuring tissue mechanics meet functional requirements. However the IFM is poorly defined, therefore tendon structure-function relationships are incompletely understood. We hypothesised that the IFM has a more complex proteome, with faster turnover than the fascicular matrix (FM). Using laser-capture microdissection and mass spectrometry, we demonstrate that the IFM contains more ...
Hirst SJ, Martin JG, Bonacci JV, Chan V, Fixman ED, Hamid QA, Herszberg B, Lavoie JP, McVicker CG, Moir LM, Nguyen TT, Peng Q, Ramos-Barbón D....Increased airway smooth muscle (ASM) mass is perhaps the most important component of the airway wall remodeling process in asthma. Known mediators of ASM proliferation in cell culture models fall into 2 categories: those that activate receptors with intrinsic receptor tyrosine kinase activity and those that have their effects through receptors linked to heterotrimeric guanosine triphosphate-binding proteins. The major candidate signaling pathways activated by ASM mitogens are those dependent on extracellular signal-regulated kinase and phosphoinositide 3'-kinase. Increases in ASM mass may also...
Bi X, Yang X, Bostrom MP, Camacho NP.Significant complications in the management of osteoarthritis (OA) are the inability to identify early cartilage changes during the development of the disease, and the lack of techniques to evaluate the tissue response to therapeutic and tissue engineering interventions. In recent studies several spectroscopic parameters have been elucidated by Fourier transform infrared imaging spectroscopy (FT-IRIS) that enable evaluation of molecular and compositional changes in human cartilage with progressively severe OA, and in repair cartilage from animal models. FT-IRIS permits evaluation of early-stag...
Bi X, Li G, Doty SB, Camacho NP.The orientation of collagen molecules is an important determinant of their functionality in connective tissues. The objective of the current study is to establish a method to determine the alignment of collagen molecules in histological sections of cartilage by polarized Fourier transform infrared imaging spectroscopy (FT-IRIS), a method based on molecular vibrations. Methods: Polarized FT-IRIS data obtained from highly oriented tendon collagen were utilized to calibrate the derived spectral parameters. The ratio of the integrated areas of the collagen amide I/II absorbances was used as an ind...
Carter CA, Jolly DG, Worden CE, Hendren DG, Kane CJ.Nonhealing wounds of the lower equine limb represent a challenging model. The platelet is a natural source of a myriad of growth factors and cytokines that promote wound healing. This study evaluates the potential of platelet derived factors to enhance wound healing in the lower equine limb. Platelets were isolated from horse blood and activated with thrombin, a process known to induce growth factor release. This produced a platelet gel composed of platelet-rich plasma (PRP). To test this all-natural wound healant, 2.5-cm(2) full thickness cutaneous wounds were created below the knee and hock ...
Mansfield J, Yu J, Attenburrow D, Moger J, Tirlapur U, Urban J, Cui Z, Winlove P.A combination of two-photon fluorescence (TPF), second harmonic generation (SHG) and coherent anti-Stokes Raman scattering (CARS) imaging has been used to investigate the elastin fibre network in healthy equine articular cartilage from the metacarpophalangeal joint. The elastin fibres were identified using their intrinsic two-photon fluorescence and immuno-staining was used to confirm the identity of these fibres. SHG was used to reveal the collagen matrix and the collagen fibre orientations were determined from their SHG polarization sensitivity, while CARS was used to clearly delineate the c...
Taylor SE, Vaughan-Thomas A, Clements DN, Pinchbeck G, Macrory LC, Smith RK, Clegg PD.There is a paucity of data regarding molecular markers that identify the phenotype of the tendon cell. This study aims to quantify gene expression markers that distinguish between tendon fibroblasts and other mesenchymal cells which may be used to investigate tenogenesis. Methods: Expression levels for 12 genes representative of musculoskeletal tissues, including the proposed tendon progenitor marker scleraxis, relative to validated reference genes, were evaluated in matched samples of equine tendon (harvested from the superficial digital flexor tendon), cartilage and bone using quantitative P...
Hegewald AA, Ringe J, Bartel J, Krüger I, Notter M, Barnewitz D, Kaps C, Sittinger M.Mesenchymal stem cells (MSC) have the potential to differentiate into distinct mesenchymal tissues including cartilage, which suggest these cells as an attractive cell source for cartilage tissue engineering approaches. Our objective was to study the effects of TGF-beta1, hyaluronic acid and synovial fluid on chondrogenic differentiation of equine MSC. For that, bone marrow was aspirated from the tibia of one 18-month-old horse (Haflinger) and MSC were isolated using percoll-density centrifugation. To promote chondrogenesis, MSC were centrifuged to form a micromass and were cultured in a mediu...
Broeckx S, Zimmerman M, Crocetti S, Suls M, Mariën T, Ferguson SJ, Chiers K, Duchateau L, Franco-Obregón A, Wuertz K, Spaas JH.Degenerative joint disease (DJD) is a major cause of reduced athletic function and retirement in equine performers. For this reason, regenerative therapies for DJD have gained increasing interest. Platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) were isolated from a 6-year-old donor horse. MSCs were either used in their native state or after chondrogenic induction. In an initial study, 20 horses with naturally occurring DJD in the fetlock joint were divided in 4 groups and injected with the following: 1) PRP; 2) MSCs; 3) MSCs and PRP; or 4) chondrogenic induced MSCs and PRP. The ho...
Visser J, Levett PA, te Moller NC, Besems J, Boere KW, van Rijen MH, de Grauw JC, Dhert WJ, van Weeren PR, Malda J.Decellularized tissues have proven to be versatile matrices for the engineering of tissues and organs. These matrices usually consist of collagens, matrix-specific proteins, and a set of largely undefined growth factors and signaling molecules. Although several decellularized tissues have found their way to clinical applications, their use in the engineering of cartilage tissue has only been explored to a limited extent. We set out to generate hydrogels from several tissue-derived matrices, as hydrogels are the current preferred cell carriers for cartilage repair. Equine cartilage, meniscus, a...
Williams IF, McCullagh KG, Silver IA.During tissue response to injury the glycoproteins fibronectin and Type III collagen are synthesized in increased amounts. We have studied the distribution of these molecules in the healing tendon at various times after injury by comparison with that of the major constituent of normal tendon, Type I collagen. Immunofluorescent localization demonstrated the presence of fibronectin throughout the tendon within one week after injury. Staining was found in the matrix, both around capillaries and around fibroblast-like cells. Fibronectin was still apparent in the healing tendon at one month after i...
Romero A, Barrachina L, Ranera B, Remacha AR, Moreno B, de Blas I, Sanz A, Vázquez FJ, Vitoria A, Junquera C, Zaragoza P, Rodellar C.Several therapies have been investigated for equine tendinopathies, but satisfactory long term results have not been achieved consistently and a better understanding of the healing mechanism elicited by regenerative therapies is needed. The aim of this study was to assess the separate effects of autologous bone marrow (BM) and adipose tissue (AT) derived mesenchymal stem cells (MSCs), and platelet rich plasma (PRP), for treating lesions induced in the superficial digital flexor tendon (SDFT) of horses. Lesions were created surgically in both SDFTs of the forelimbs of 12 horses and were treated...
Caliari SR, Harley BA.Biomolecular environments encountered in vivo are complex and dynamic, with combinations of biomolecules presented in both freely diffusible (liquid-phase) and sequestered (bound to the extracellular matrix) states. Strategies for integrating multiple biomolecular signals into a biomimetic scaffold provide a platform to simultaneously control multiple cell activities, such as motility, proliferation, phenotype, and regenerative potential. Here we describe an investigation elucidating the influence of the dose and mode of presentation (soluble, sequestered) of five biomolecules (stromal cell-de...
