Gene expression in horses involves the process by which information from a gene is used to synthesize functional gene products, such as proteins, that contribute to the horse's physiological and developmental processes. This process is fundamental to understanding how genetic information is translated into observable traits in horses. Gene expression studies in equines can provide insights into various aspects of horse biology, including growth, metabolism, immune response, and adaptation to environmental changes. Researchers utilize techniques such as RNA sequencing and quantitative PCR to analyze gene expression patterns in different tissues and under various conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and implications of gene expression in equine biology and health.
Riveroll AL, Skyba-Lewin S, Lynn KD, Mubyeyi G, Abd-El-Aziz A, Kibenge FST, Kibenge MJT, Cohen AM, Esparza-Gonsalez B, McD￮ L, Montelpare WJ.Adipose-derived stem cells (ADSCs) are used in tissue regeneration therapies. The objective of this study is to identify stable reference genes (RGs) for use in gene expression studies in a characterized equine adipose-derived mesenchymal stem cell (EADMSC) differentiation model. ADSCs were differentiated into adipocytes (ADs) or osteoblasts (OBs), and the proteomes from these cells were analyzed by liquid chromatography tandem mass spectrometry. Proteins that were stably expressed in all three cells types were identified, and the mRNA expression stabilities for their corresponding genes were ...
Yu J, Wang Z, Wang F, Yang G, Cheng J, Ji C, Li M, Liu B, Wang Y, Dang R.Testicular development and spermatogenesis are tightly regulated by the number of genes and noncoding genes, and mRNAs and lncRNAs play vital roles in regulating posttranscriptional gene expression. However, mRNAs and lncRNAs have not been systematically identified in the testes of donkeys. In this study, mRNA and lncRNA expression profiles in the testes of DeZhou donkeys between 2 months and 2 years of age were comprehensively analysed by RNA sequencing. We identified 56,605 lncRNAs and 61,857 mRNAs by gene expression analysis, and 21,845 lncRNAs (p < .05) and 14,109 mRNAs (p < .0...
Pechanec MY, Beall JM, Katzman S, Maga EA, Mienaltowski MJ.Tendinopathies remain the leading contributor to career-ending injuries in horses because of the complexity of tendon repair. As such, cell-based therapies like injections of adipose-derived mesenchymal stem cells (ADMSCs, or MSCs) into injured tendons are becoming increasingly popular though their long-term efficacy on a molecular and wholistic level remains contentious. Thus, we co-cultured equine MSCs with intrinsic (tendon proper) and extrinsic (peritenon) tendon cell populations to examine interactions between these cells. Gene expression for common tenogenic, perivascular, and differenti...
Bone reportsJanuary 5, 2023
Volume 18 101653 doi: 10.1016/j.bonr.2023.101653
Grissom SK, Semevolos SA, Duesterdieck-Zellmer K.The objective of this study is to better understand the pathogenesis of early equine osteochondrosis (OC) by identifying differences in gene and protein expression of extracellular matrix components and regulators in normal and diseased cartilage and bone, focusing on the osteochondral junction and cells surrounding the cartilage canals. We expected to find an upregulation of matrix metalloproteinases and a decrease in extracellular matrix constituent expression along the osteochondral junction and cells surrounding the cartilage canals in OC samples. Paraffin-embedded osteochondral samples (6...
Naboulsi R, Cieślak J, Headon D, Jouni A, Negro JJ, Andersson G, Lindgren G.Gene expression differences can assist in characterizing important underlying genetic mechanisms between different phenotypic traits. However, when population-dense tissues are studied, the signals from scarce populations are diluted. Therefore, appropriately choosing a sample collection method that enriches a particular type of effector cells might yield more specific results. To address this issue, we performed a polyA-selected RNA-seq experiment of domestic horse () plucked-hair samples and skin biopsies. Then, we layered the horse gene abundance results against cell type-specific marker ge...
Smith EJ, Beaumont RE, McClellan A, Sze C, Palomino Lago E, Hazelgrove L, Dudhia J, Smith RKW, Guest DJ.Tendon injuries occur commonly in both human and equine athletes, and poor tendon regeneration leads to functionally deficient scar tissue and an increased frequency of re-injury. Despite evidence suggesting inadequate resolution of inflammation leads to fibrotic healing, our understanding of the inflammatory pathways implicated in tendinopathy remains poorly understood, meaning successful targeted treatments are lacking. Here, we demonstrate IL-1β, TNFα and IFN-γ work synergistically to induce greater detrimental consequences for equine tenocytes than when used individually. This includes ...
Padoan E, Ferraresso S, Pegolo S, Barnini C, Castagnaro M, Bargelloni L.Mild equine asthma (MEA) and severe equine asthma (SEA) are two of the most frequent equine airway inflammatory diseases, but knowledge about their pathogenesis is limited. The goal of this study was to investigate gene expression differences in the respiratory tract of MEA- and SEA-affected horses and their relationship with clinical signs. Methods: Clinical examination and endoscopy were performed in 8 SEA- and 10 MEA-affected horses and 7 healthy controls. Cytological and microbiological analyses of bronchoalveolar lavage (BAL) fluid were performed. Gene expression profiling of BAL fluid wa...
Padjasek M, Qasem B, Cisło-Pakuluk A, Marycz K.Cyclosporine A (CsA) is a selective and reversible immunosuppressant agent that is widely used as a medication for a wide spectrum of diseases in humans such as graft versus host disease, non-infectious uveitis, rheumatoid arthritis, psoriasis, and atopic dermatitis. Furthermore, the CsA is used to treat keratoconjunctivitis sicca, chronic superficial keratitis, immune-mediated keratitis and equine recurrent uveitis in animals. The selective activity of Cyclosporine A (CsA) was demonstrated to be an immunomodulation characteristic of T-lymphocyte proliferation and inhibits cytokine gene expres...
Diel de Amorim M, Bramer SA, Rajamanickam GD, Klein C, Card C.Our objectives were to examine changes in endometrial and luteal gene expression during estrus, diestrus, pregnancy and treatments to induce luteolysis and putatively induce luteostasis. Groups were: Diestrus (DIEST), Estrus (ESTR), Pregnant (PREG), Oxytocin (OXY), Carbetocin (CARB), and Meclofenamic acid (MFA). Blood was obtained from day (D)12 to D15 for measurement of oxytocinase, also referred to as leucyl-cysteinyl aminopeptidase (LNPEP) and progesterone. Luteal biopsies were obtained on D12 and D15 and an endometrial biopsy on D15. Real-time RT-PCR was performed for the following genes: ...
Sage SE, Nicholson P, Peters LM, Leeb T, Jagannathan V, Gerber V.The transcriptomic profile of a cell population can now be studied at the cellular level using single-cell mRNA sequencing (scRNA-seq). This novel technique provides the unprecedented opportunity to explore the cellular composition of the bronchoalveolar lavage fluid (BALF) of the horse, a species for which cell type markers are poorly described. Here, scRNA-seq technology was applied to cryopreserved equine BALF cells. Analysis of 4,631 cells isolated from three asthmatic horses in remission identified 16 cell clusters belonging to six major cell types: monocytes/macrophages, T cells, B/plasm...
Hernandez SM, Begum L, Keller LE, Fu Q, Zhang S, Fortier LA.To identify chondroprotective factors as potential disease-modifying osteoarthritis treatments using an unbiased, bottom-up proteomics approach. Methods: Paired equine cartilage explants and synovial membrane were collected postmortem from 4 horses with no history of lameness and grossly normal joints at necropsy. Methods: Six groups were established: cartilage, synoviocytes, and cartilage + synoviocytes (coculture), all with or without interleukin (IL)-1β. The catabolic effect of IL-1β was verified by glycosaminoglycan (GAG) released from cartilage into media by 1,9-dimethyl-methylene blue ...
Ząbek T, Witarski W, Semik-Gurgul E, Szmatoła T, Kowalska K, Samiec M.Ex vivo expansion of chondrocytes in monolayer (ML) culture for therapeutic purposes is burdened with difficulties related to the loss of cartilaginous phenotype. Epigenetic mechanisms responsible for regulation of gene expression are believed to underlie chondrocyte dedifferentiation. We have inspected the relevance of DNA methylation alterations for passage-related differential expression of NFATC1 gene involved in hard connective tissue turnover and development, NADSYN1 influencing redox metabolism, and JAK3 - an important driver of inflammation. We have assessed relative amount of transcri...
Loux S, Robles M, Chavatte-Palmer P, de Mestre A.Development and the subsequent function of the fetal membranes of the equine placenta require both complex and precise regulation of gene expression. Advancements in recent years in bioinformatic techniques have allowed more extensive analyses into gene expression than ever before. This review starts by combining publically available transcriptomic data sets obtained from a range of embryonic, placental and maternal tissues, with previous knowledge of equine placental development and physiology, to gain insights into key gene families relevant to placentation in the horse. Covering the whole o...
Fukuda K, Kuroda T, Tamura N, Mita H, Miyata H, Kasashima Y.This study aimed to verify the effects of platelet lysate (PL) administration on the repair of injured horse tissue. Skeletal muscle injuries were induced in 26 Thoroughbreds by bupivacaine administration. PL or saline was administered 1 day (1D) after injury. Muscle samples from 22 horses injected with PL or saline were obtained by needle biopsy at 2, 3, 4, or 7 days (2D, 3D, 4D, or 7D, respectively) after injury, and growth-factor concentrations and muscle regeneration-associated gene expression levels were determined. Intact samples were similarly collected before injury, and samples of inj...
Domingues RR, Ginther OJ, Gomez-Leon V, Castro T, Wiltbank MC.In heifers and mares, multiple pulses of prostaglandin F2alpha (PGF) are generally associated with complete luteal regression. Although PGF pulses occur before and during luteolysis, little is known about the role of minor PGF pulses during preluteolysis on subsequent luteal and endometrial PGF production that may initiate luteolysis. Heifers (n = 7/group) and mares (n = 6/group) were treated with a single minor dose of PGF (3.0 and 0.5 mg, respectively) during mid-luteal phase (12 and 10 days postovulation respectively). After treatment, a transient decrease in progesterone (P4) con...
Castro T, Jacob JC, Domingues RR, Ginther OJ.Prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) are involved in equine embryo mobility throughout the uterus on Days 11-15 (ovulation = Day 0). On a day (Day 12) of maximal embryo mobility in pregnant mares (n = 13) and before luteolysis in nonbred mares (n = 10), gene expressions were compared between the uterine horns that did and did not contain the mobile embryo and between pregnant and nonbred mares. A cytobrush was used to collect an endometrial sample from the middle of each uterine horn. In nonbred mares, there was no difference for any of the considered gene expressions ...
Patterson Rosa L, Mallicote MF, MacKay RJ, Brooks SA.Macrolide drugs are the treatment of choice for infections, despite severe side-effects temporary anhidrosis as a. To better understand the molecular biology leading to macrolide induced anhidrosis, we performed skin biopsies and Quantitative Intradermal Terbutaline Sweat Tests (QITSTs) in six healthy pony-cross foals for three different timepoints during erythromycin administration-pre-treatment (baseline), during anhidrosis and post-recovery. RNA sequencing of biopsies followed by differential gene expression analysis compared both pre and post normal sweating timepoints to the erythromycin...
Arévalo-Turrubiarte M, Baratta M, Ponti G, Chiaradia E, Martignani E.Mesenchymal stem cells (MSCs) have been used therapeutically in equine medicine. MSCs release extracellular vesicles (EVs), which affect cell processes by inhibiting cell apoptosis and regulating inflammation. To date, little is known about equine EVs and their regenerative properties. Objective: To characterise equine MSC-derived extracellular vesicles (EVs) and evaluate their effect on equine chondrocytes treated with pro-inflammatory cytokines in vitro. Methods: In vitro experiments with randomised complete block design. Methods: Mesenchymal stem cells from bone marrow, adipose tissue, and ...
Haneda S, Dini P, Esteller-Vico A, Scoggin KE, Squires EL, Troedsson MH, Daels P, Nambo Y, Ball BA.A sufficient vascular network within the feto-maternal interface is necessary for placental function. Several pregnancy abnormalities have been associated with abnormal vascular formations in the placenta. We hypothesized that growth and expansion of the placental vascular network in the equine () placenta is regulated by estrogens (estrogen family hormones), a hormone with a high circulating concentration during equine gestation. Administration of letrozole, a potent and specific inhibitor of aromatase, during the first trimester (D30 to D118), decreased circulatory estrone sulfate concentrat...
Rouge M, Elkhatib R, Delalande C, Cognié J, Reigner F, Barriere P, Deleuze S, Cousty M, Legendre F, Galera P, Hanoux V, Bouraima-Lelong H.Although vitamin D acts in various biological processes, it plays a critical role in the maintenance of bone health, and regulates calcium homeostasis. In humans and rodents, the main tissues involved in vitamin D metabolism are the liver and the kidneys, however it has been shown that the testis has strongly participated in its bioactivation. Indeed, in these different species, enzymes metabolizing vitamin D (CYP27A1, CYP27B1 and CYP2R1) have been demonstrated in this tissue. Moreover, men with hypogonadism have shown a decrease in circulating levels of vitamin D. In equine species, the castr...
Walters M, Skovgaard K, Andersen PH, Heegaard PMH, Jacobsen S.The role of resident cells such a synoviocytes and chondrocytes in intra-articular inflammation is well-characterized, however the in vivo gene expression patterns of cells (predominantly leukocytes) in the synovial fluid (SF) of an inflamed joint have never previously been investigated. The aim of this study was to investigate gene expression in SF leukocytes from the inflamed joint cavity after intra-articular lipopolysaccharide (LPS) injection in horses to improve our understanding of the temporal regulation of the intra-articular inflammatory response. Gene expression was investigated in S...
Goszczynski DE, Tinetti PS, Choi YH, Ross PJ, Hinrichs K.Embryonic genome activation and dosage compensation are major genetic events in early development. Combined analysis of single embryo RNA-seq data and parental genome sequencing was used to evaluate parental contributions to early development and investigate X-chromosome dynamics. In addition, we evaluated dimorphism in gene expression between male and female embryos. Evaluation of parent-specific gene expression revealed a minor increase in paternal expression at the 4-cell stage that increased at the 8-cell stage. We also detected eight genes with allelic expression bias that may have an imp...
Mok CH, MacLeod JN.Within developing synovial joints, interzone and anlagen cells progress through divergent chondrogenic pathways to generate stable articular cartilage and transient hypertrophic anlagen cartilage, respectively. Understanding the comparative cell biology between interzone and anlagen cells may provide novel insights into emergent cell-based therapies to support articular cartilage regeneration. The aim of this study was to assess the kinetics of gene expression profiles in these skeletal cell lines after inducing chondrogenesis in culture. Interzone and anlagen cells from seven equine fetuses w...
Vercelli C, Tursi M, Miretti S, Giusto G, Gandini M, Re G, Valle E.Laminitis is one of the most devastating diseases in equine medicine, and although several etiopathogenetic mechanisms have been proposed, few clear answers have been identified to date. Several lines of evidence point towards its underlying pathology as being metabolism-related. In the carbonyl stress pathway, sugars are converted to methylglyoxal (MG)-a highly reactive α-oxoaldehyde, mainly derived during glycolysis in eukaryotic cells from the triose phosphates: D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. One common hypothesis is that MG could be synthesized during the dig...
Gaesser AM, Underwood C, Linardi RL, Even KM, Reef VB, Shetye SS, Mauck RL, King WJ, Engiles JB, Ortved KF.Autologous protein solution (APS) has been used anecdotally for intralesional treatment of tendon and ligament injuries, however, its use in these injuries has never been studied . Our objective was to evaluate the effect of APS on tendon healing in an equine superficial digital flexor (SDF) tendonitis model. We hypothesized intralesional injection of APS would result in superior structural and biomechanical healing. SDF tendonitis was induced in both forelimbs of eight horses using collagenase injection. One forelimb was randomly assigned to receive an intralesional injection of APS, while th...
Bradbery AN, Coverdale JA, Hammer CJ, Dunlap KA, Leatherwood JL, Satterfield MC.Skeletal muscle plays an integral role in the ability of a horse to perform at high levels. Shifts in skeletal muscle development in response to maternal plane of nutrition may have substantial and lasting impacts on athletic performance and whole-body metabolism. Therefore, sixteen Quarter Horse mares were used in a completely randomized design and maintained at a body condition score (BCS) 6 until start of third trimester. On d 235 of gestation, mares were randomly assigned to receive one of two dietary treatments with a diet formulated to meet requirements during late gestation (CON; n = ...
Oreff GL, Fenu M, Vogl C, Ribitsch I, Jenner F.For research on tendon injury, many different animal models are utilized; however, the extent to which these species simulate the clinical condition and disease pathophysiology has not yet been critically evaluated. Considering the importance of inflammation in tendon disease, this study compared the cellular and molecular features of inflammation in tenocytes of humans and four common model species (mouse, rat, sheep, and horse). While mouse and rat tenocytes most closely equalled human tenocytes' low proliferation capacity and the negligible effect of inflammation on proliferation, the wound...
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...
Jiang Z, Chen JW, Haughan J, Stefanovski D, Soma LR, Robinson MA.Extracorporeal shockwave therapy (ESWT) is a treatment applied to musculoskeletal injuries in equine athletes to alleviate pain and accelerate healing. ESWT also causes acute tissue damage. Therefore, its ability to act as an analgesic and cause tissue damage potentially increases the risk of a catastrophic event if used shortly before a strenuous competition such as horseracing. While ESWT is prohibited by many racing jurisdictions within 10 days prior to competition, a test to detect whether a horse has received ESWT is needed. ESWT changes the protein levels of inflammatory mediators in bl...
Turlo AJ, McDermott BT, Barr ED, Riggs CM, Boyde A, Pinchbeck GL, Clegg PD.Osteoarthritis (OA) is a disease of the entire joint but the relationship between pathological events in various joint tissues is poorly understood. We examined concurrent changes in bone, cartilage, and synovium in a naturally occurring equine model of joint degeneration. Joints (n = 64) were grossly assessed for palmar/plantar osteochondral disease (POD) in racehorses that required euthanasia for unrelated reasons and assigned a grade of 0 (n = 34), 1 (n = 17), 2 or 3 (n = 13) using a recognized grading scheme. Synovium, cartilage, and subchondral bone were collected for hist...
Nieto JE, MacDonald MH, Braim AE, Aleman M.Horses are exquisitely sensitive to bacterial endotoxin and endotoxaemia is common in colic cases. In this study, gene expression of inflammatory cytokines was characterised in the blood of healthy horses following i.v. administration of lipopolysaccharide (LPS). Six horses received an LPS infusion and 6 controls received an equivalent volume of saline. Gene expression of genes encoding interleukin (IL)-1alpha, IL-1beta, IL-6, IL-8, and tumour necrosis factor-alpha (TNF-alpha) was quantified by real-time PCR. Gene expression of all inflammatory cytokines was upregulated following administratio...
Tung JT, Arnold CE, Alexander LH, Yuzbasiyan-Gurkan V, Venta PJ, Richardson DW, Caron JP.To determine the effects of prostaglandin E2 (PGE2) on recombinant equine interleukin (IL)-1beta-stimulated expression of matrix metalloproteinases (MMP 1, MMP 3, MMP 13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP 1) in vitro. Methods: Cultured equine chondrocytes. Methods: Stationary monolayers of first-passage chondrocytes were exposed to graduated concentrations of PGE2 with or without a subsaturating dose (50 pg/ml) of recombinant equine IL-1beta (reIL-1beta) to induce expression of MMP 1, MMP 3, MMP 13, and TIMP 1, followed by RNA isolation and northern blotting. In subseque...
Carmona JU, Ríos DL, López C, Álvarez ME, Pérez JE, Bohórquez ME.Platelet-rich plasma (PRP) preparations are a common treatment in equine osteoarthritis (OA). However, there are controversies regarding the ideal concentration of platelets and leukocytes in these biological substances necessary to induce an adequate anti-inflammatory and anabolic response in articular cartilage. The aims were to study the influence of leukocyte- and platelet-rich gel (L-PRG) and pure platelet-rich gel (P-PRG) supernatants on the histological changes of cartilage, the degree of chondrocyte apoptosis, the production of hyaluronan (HA) and the gene expression of nuclear factor ...
Oreff GL, Fenu M, Vogl C, Ribitsch I, Jenner F.For research on tendon injury, many different animal models are utilized; however, the extent to which these species simulate the clinical condition and disease pathophysiology has not yet been critically evaluated. Considering the importance of inflammation in tendon disease, this study compared the cellular and molecular features of inflammation in tenocytes of humans and four common model species (mouse, rat, sheep, and horse). While mouse and rat tenocytes most closely equalled human tenocytes' low proliferation capacity and the negligible effect of inflammation on proliferation, the wound...
Textor JA, Clark KC, Walker NJ, Aristizobal FA, Kol A, LeJeune SS, Bledsoe A, Davidyan A, Gray SN, Bohannon-Worsley LK, Woolard KD, Borjesson DL.Distal extremity wounds are a significant clinical problem in horses and humans and may benefit from mesenchymal stem cell (MSC) therapy. This study evaluated the effects of direct wound treatment with allogeneic stem cells, in terms of gross, histologic, and transcriptional features of healing. Three full-thickness cutaneous wounds were created on each distal forelimb in six healthy horses, for a total of six wounds per horse. Umbilical cord-blood derived equine MSCs were applied to each wound 1 day after wound creation, in one of four forms: (a) normoxic- or (b) hypoxic-preconditioned cells ...
de Laat MA, Pollitt CC, Kyaw-Tanner MT, McGowan CM, Sillence MN.The reason why a sustained high concentration of insulin induces laminitis in horses remains unclear. Cell proliferation occurs in the lamellae during insulin-induced laminitis and in other species high concentrations of insulin can activate receptors for the powerful cell mitogen, insulin-like growth factor (IGF)-1. The first aim of this study was to determine if IGF-1 receptors (IGF-1R) are activated in the hoof during insulin-induced laminitis. Gene expression for IGF-1R and the insulin receptor (InsR) was measured using qRT-PCR, in lamellar tissue from control horses and from horses underg...
Schneberger D, Caldwell S, Suri SS, Singh B.Toll-like receptor 9 (TLR9) has been found to be the main receptor to respond to bacterial DNA in a wide variety of species. Recent work has shown that TLR9 is expressed in a diverse set of cells within the lung. However, much of this data has been centered on human and mouse cell culture lines or primary cultures and very little is known of TLR9 expression in intact lung, especially that of the horse. Here we show that TLR9 is expressed in the lungs of horses in a wide variety of cells. In particular, we note expression in pulmonary intravascular macrophages (PIMs), alveolar macrophages, bron...
Miyabara S, Yuda Y, Kasashima Y, Kuwano A, Arai K.Tenomodulin has been recognized as a biomarker for tendon differentiation, and its gene expression is regulated by several transcription factors including Scleraxis and Mohawk. In this study, we found a novel regulatory mechanism of tenomodulin expression. Equine bone marrow-derived mesenchymal stem cells (BMSCs) in monolayer culture showed a low mRNA level of tenomodulin in comparison with the level in the tendon. When cultured in collagen gel containing a glycogen synthase kinase-3 (GSK-3) inhibitor (BIO), expression of tenomodulin in BMSCs increased up to the level in the tendon. Participat...
Tew SR, McDermott BT, Fentem RB, Peffers MJ, Clegg PD.Messenger RNA (mRNA) decay rates control not only gene expression levels, but also responsiveness to altered transcriptional input. We undertook this study to examine transcriptome-wide posttranscriptional regulation in both normal and osteoarthritic (OA) human articular chondrocytes. Methods: Human articular chondrocytes were isolated from normal or OA tissue. Equine articular chondrocytes were isolated from young or old horses at a commercial abattoir. RNA decay was measured across the transcriptome in human cells by microarray analysis following an actinomycin D chase. Messenger RNA levels ...
Naccache F, Metzger J, Distl O.Osteochondrosis (OC) is an injury to cartilage canals with a following necrosis in the growth cartilage, from there it can develop to osteochondrosis dissecans (OCD). Due to its high impact in the equine industry, new insights into predisposing factors and potential high-risk genetic variants are warranted. This article reviews advancements in quantitative and molecular genetics in refining estimation of genetic parameters and identifying predisposing genetic loci. Heritabilities were highest for hock OC with estimates at 0.29-0.46 in Hanoverian warmblood and Norwegian trotters, whereas in Tho...
Velloso Alvarez A, Boone LH, Pondugula SR, Caldwell F, Wooldridge AA.Autologous conditioned serum (ACS) and autologous protein solution (APS) are newer therapeutic options for osteoarthritis (OA). Co-culture of cartilage and synovium stimulated with IL-1β produces a similar physiologic response to tissues from naturally-ocurring OA. The study objective was to investigate the effects of ACS, APS, and triamcinolone (TA) on inflammatory and catabolic gene expression of inflamed joint tissues in co-culture. Blood was collected and processed for ACS and APS from six horses. Cartilage and synovial explants were harvested from the stifle, placed in co-culture, and tr...
Ranera B, Remacha AR, Álvarez-Arguedas S, Romero A, Vázquez FJ, Zaragoza P, Martín-Burriel I, Rodellar C.Mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (AT-MSCs) are being applied to equine cell therapy. The physiological environment in which MSCs reside is hypoxic and does not resemble the oxygen level typically used in in vitro culture (20% O2). This work compares the growth kinetics, viability, cell cycle, phenotype and expression of pluripotency markers in both equine BM-MSCs and AT-MSCs at 5% and 20% O2. Results: At the conclusion of culture, fewer BM-MSCs were obtained in hypoxia than in normoxia as a result of significantly reduced cell division. Hypoxi...
Barrey E, Mucher E, Jeansoule N, Larcher T, Guigand L, Herszberg B, Chaffaux S, Guérin G, Mata X, Benech P, Canale M, Alibert O, Maltere P, Gidrol X.Several cases of myopathies have been observed in the horse Norman Cob breed. Muscle histology examinations revealed that some families suffer from a polysaccharide storage myopathy (PSSM). It is assumed that a gene expression signature related to PSSM should be observed at the transcriptional level because the glycogen storage disease could also be linked to other dysfunctions in gene regulation. Thus, the functional genomic approach could be conducted in order to provide new knowledge about the metabolic disorders related to PSSM. We propose exploring the PSSM muscle fiber metabolic disorder...
Martin AM, Elliott JA, Duffy P, Blake CM, Ben Attia S, Katz LM, Browne JA, Gath V, McGivney BA, Hill EW, Murphy BA.Circadian rhythms are innate 24-h cycles in behavioral and biochemical processes that permit physiological anticipation of daily environmental changes. Elucidating the relationship between activity rhythms and circadian patterns of gene expression may contribute to improved human and equine athletic performance. Six healthy, untrained mares were studied to determine whether locomotor activity behavior and skeletal muscle gene expression reflect endogenous circadian regulation. Activity was recorded for three consecutive 48-h periods: as a group at pasture (P), and individually stabled under a ...
Toth AM, Geisler C, Aumiller JJ, Jarvis DL.In an effort to produce processed, soluble Western equine encephalitis virus (WEEV) glycoproteins for subunit therapeutic vaccine studies, we isolated twelve recombinant baculoviruses designed to express four different WEEV glycoprotein constructs under the transcriptional control of three temporally distinct baculovirus promoters. The WEEV glycoprotein constructs encoded full-length E1, the E1 ectodomain, an E26KE1 polyprotein precursor, and an artificial, secretable E2E1 chimera. The three different promoters induced gene expression during the immediate early (ie1), late (p6.9), and very lat...
Zou X, Zou L, Foldager C, Bendtsen M, Feng W, Bünger CE.To elucidate the molecular mechanisms of spinal fusion with different graft materials during an anterior lumbar interbody fusion, we examined the gene-expression profiles after implantation of equine bone protein extract, rhBMP-2 and autograft using microarray technology and data analysis, including hierarchical clustering, self-organizing maps (SOM), KEGG pathway and Biological process GO analyses in a porcine model. The results suggest that equine bone protein extract exhibited a more similar expression pattern with autograft than that of rhBMP-2. rhBMP-2 recruits progenitor cells, prolifera...
Katavolos P, Ackerley CA, Viel L, Clark ME, Wen X, Bienzle D.Horses are prone to recurrent airway obstruction (RAO), an inflammatory lung disease induced by repeated exposure to environmental mold, dust, and bacterial components. Active disease manifests with mucus hyperproduction, neutrophilic inflammation, bronchoconstriction, and coughing. Chronically affected animals have lung remodeling characterized by smooth muscle hyperplasia, collagen deposition, lymphoid hyperplasia, and impaired aerobic performance. Clara cell secretory protein (CCSP) counters inflammation in the lung, hence we hypothesized that CCSP depletion is a key feature of RAO in horse...
Belknap JK, Giguère S, Pettigrew A, Cochran AM, Van Eps AW, Pollitt CC.Recent research has indicated that inflammation plays a role in the early stages of laminitis and that, similar to organ failure in human sepsis, early inflammatory mechanisms may lead to downstream events resulting in lamellar failure. Characterisation of the type of immune response (i.e. innate vs. adaptive) is essential in order to develop therapeutic strategies to counteract these deleterious events. Objective: To quantitate gene expression of pro-inflammatory cytokines known to be important in the innate and adaptive immune response during the early stages of laminitis, using both the bla...
Lansade L, Valenchon M, Foury A, Neveux C, Cole SW, Layé S, Cardinaud B, Lévy F, Moisan MP.The use of environmental enrichment (EE) has grown in popularity over decades, particularly because EE is known to promote cognitive functions and well-being. Nonetheless, little is known about how EE may affect personality and gene expression. To address this question in a domestic animal, 10-month-old horses were maintained in a controlled environment or EE for 12 weeks. The control horses (n = 9) lived in individual stalls on wood shaving bedding. They were turned out to individual paddocks three times a week and were fed three times a day with pellets or hay. EE-treated horses (n =...
Zhang YW, Davis EG, Bai J.Quantitative reverse transcription polymerase chain reaction (RT-PCR) has become a basic, reliable and sensitive modern technique, in both biological research and clinical diagnosis, for investigation of gene expression and validation of cDNA microarray analysis. Accurate mRNA quantification using quantitative RT-PCR commonly requires data normalization through stable housekeeping genes (HKGs). Selection of HKGs for data normalization is critical for accurate mRNA quantification. Our objective was to evaluate a set of candidate HKGs as internal controls for gene expression studies using quanti...
Jacobson E, Dart AJ, Mondori T, Horadogoda N, Jeffcott LB, Little CB, Smith MM.It is not known how extensively a localised flexor tendon injury affects the entire tendon. This study examined the extent of and relationship between histopathologic and gene expression changes in equine superficial digital flexor tendon after a surgical injury. One forelimb tendon was hemi-transected in six horses, and in three other horses, one tendon underwent a sham operation. After euthanasia at six weeks, transected and control (sham and non-operated contralateral) tendons were regionally sampled (medial and lateral halves each divided into six 3 cm regions) for histologic (scoring and ...
Donadeu FX, Fahiminiya S, Esteves CL, Nadaf J, Miedzinska K, McNeilly AS, Waddington D, Gérard N.Several aspects of equine ovarian physiology are unique among domestic species. Moreover, follicular growth patterns are very similar between horses and humans. This study aimed to characterize, for the first time, global gene expression profiles associated with growth and preovulatory (PO) maturation of equine dominant follicles. Granulosa cells (GCs) and theca interna cells (TCs) were harvested from follicles (n = 5) at different stages of an ovulatory wave in mares corresponding to early dominance (ED; diameter ≥22 mm), late dominance (LD; ≥33 mm) and PO stage (34 h after administration...
Roth SP, Schubert S, Scheibe P, Groß C, Brehm W, Burk J.Age-related degenerative changes in tendon tissue represent a common cause for acute tendon pathologies. Although the regenerative potential of multipotent mesenchymal stromal cells (MSC) was reported to restore functionality in injured tendon tissue, cellular mechanisms of action remain partly unclear. Potential tenogenic differentiation of applied MSC is affected by various intrinsic and extrinsic factors. The current study presents an in vitro model to evaluate the combined extrinsic effects of decellularized equine tendon matrix, transforming growth factor beta 3 (TGFβ3) and bone morphoge...
Brosnahan MM, Miller DC, Adams M, Antczak DF.The invasive trophoblast cells of the equine placenta migrate into the endometrium to form endometrial cups, dense accumulations of trophoblast cells that produce equine chorionic gonadotropin between days 40 and 120 of normal pregnancy. The mechanisms by which the trophoblast cells invade the endometrium while evading maternal immune destruction are poorly defined. A gene expression microarray analysis performed on placental tissues obtained at day 34 of gestation revealed a >900-fold upregulation of mRNA encoding the cytokine IL-22 in chorionic girdle relative to noninvasive chorion. Quan...
Novakofski KD, Berg LC, Bronzini I, Bonnevie ED, Poland SG, Bonassar LJ, Fortier LA.The prevalence of osteoarthritis (OA) varies between joints. Cartilage in eight different joints was evaluated to elucidate the disparate susceptibilities between joints to post-traumatic OA (PTOA) and provide evidence for joint-specific clinical treatments. The hypothesis was that cartilage in different joints would have varying cell death and anabolic gene expression profiles after injury. Methods: Adult equine cartilage explants were harvested from shoulder (SH), elbow (EL), carpal (CA), metacarpophalangeal (MC), patellofemoral (FP), tarsal (TA), metatarsophalangeal (MT), and proximal inter...
Peffers MJ, Milner PI, Tew SR, Clegg PD.SOX9 is a transcription factor that is essential for cartilage extracellular matrix (ECM) formation. Osteoarthritis (OA) is characterised by a loss of cartilage ECM. In chondrocytes SOX9 gene expression is regulated by osmotic loading. Here we characterise SOX9 mRNA regulation through static and cyclical application of hyperosmotic conditions in normal and OA monolayer equine chondrocytes. Furthermore, we investigate whether extracellular signal-regulated protein kinase (ERK)1/2 mitogen-activated protein kinases (MAPK) pathways have a role in this regulation of SOX9. Methods: Equine chondrocyt...
Ungru J, Blüher M, Coenen M, Raila J, Boston R, Vervuert I.Fifteen obese ponies were used in a body weight (BW) reduction programme (BWRP, daily energy intake: 7.0-8.4 MJ/100 kg BW). A frequently sampled intravenous glucose tolerance test was used to assess insulin sensitivity. Subcutaneous adipose tissue biopsies of the tail head were obtained for mRNA gene expression profiles of adiponectin, retinol-binding protein 4 (RBP4), interleukin 6 (IL-6) and macrophage activation marker (CD68) before and after BWRP. Blood samples were analysed for serum leptin, serum RBP4 and plasma adiponectin. Significant BW losses occurred with 7 MJ DE/100 kg BW. Serum le...
Karagianni AE, Kapetanovic R, Summers KM, McGorum BC, Hume DA, Pirie RS.Alveolar macrophages (AMs) are the first line of defence against pathogens in the lungs of all mammalian species and thus may constitute appropriate therapeutic target cells in the treatment and prevention of opportunistic airway infections. Therefore, acquiring a better understanding of equine macrophage biology is of paramount importance in addressing this issue in relation to the horse. Objective: To compare the transcriptome of equine AMs with that of equine peritoneal macrophages (PMs) and to investigate the effect of lipopolysaccharide (LPS) on equine AM. Methods: Gene expression study o...
Campos-Chillon F, Farmerie TA, Bouma GJ, Clay CM, Carnevale EM.We hypothesised that advanced mare age is associated with follicle and oocyte gene alterations. The aims of the study were to examine quantitative and temporal differences in mRNA for LH receptor (LHR), amphiregulin (AREG) and epiregulin (EREG) in granulosa cells, phosphodiesterase (PDE) 4D in cumulus cells and PDE3A, G-protein-coupled receptor 3 (GPR3), growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and mitochondrial (mt) DNA in oocytes. Samples were collected from dominant follicles of Young (3-12 years) and Old (≥20 years) mares at 0, 6, 9 and 12h after admi...
Gebhardt S, Merkl M, Herbach N, Wanke R, Handler J, Bauersachs S.The equine endometrium exhibits characteristic morphological and functional changes during the estrous cycle controlled by the interplay of progesterone and estradiol. A microarray analysis of endometrial tissue samples derived from five time points of the estrous cycle (Day [D] 0, D3, D8, D12, and D16) was performed to study the dynamics of equine endometrial gene expression. Statistical analysis revealed 4996 genes differentially expressed during the estrous cycle. Clustering of similar expression profiles was performed to find groups of coregulated genes. This revealed eight major profiles:...
