Proteins are essential macromolecules that play diverse roles in the physiology and health of horses. They are composed of amino acids and are involved in various biological processes, including tissue growth, repair, and the synthesis of enzymes and hormones. Dietary proteins are a key component of equine nutrition, influencing muscle development, immune function, and overall performance. Horses require a balanced intake of essential amino acids, which must be obtained through their diet, as they cannot be synthesized endogenously. This page compiles peer-reviewed research studies and scholarly articles that explore the types, functions, and dietary requirements of proteins in horses, as well as their impact on equine health and performance.
Lamikanra A, Myers KA, Ferris N, Mitrophanous KA, Carroll MW.Lentiviral-based vectors hold great promise as gene delivery vehicles for the treatment of a wide variety of diseases. We have previously reported the development of a nonprimate lentiviral vector system based on the equine infectious anaemia virus (EIAV), which is able to efficiently transduce dividing and nondividing cells both in vitro and in vivo. Here, we report on the application of EIAV vectors for the systemic delivery of an antibody fusion protein designed for the treatment of cancer. The therapeutic potential of a single chain antibody against the tumour-associated antigen, 5T4, fuse...
Nieto JE, Aldridge BM, Beldomenico PM, Aleman M, Snyder JR.To determine the nucleotide sequence of the equine intestinal fatty acid binding protein (I-FABP) gene, its expression in various regions of the gastrointestinal tract, and the use of measuring I-FABP in horses with colic. Animals-86 horses with colic. Methods: The mRNA sequence for the I-FABP gene was obtained by use of a rapid amplification of complementary DNA ends technique. Comparative I-FABP gene expression was quantitated by use of a real-time reverse transcription-polymerase chain reaction assay. Amounts of I-FABP in abdominal fluid and plasma were measured by use of an ELISA kit. Asso...
Dahlgren LA, Nixon AJ.To define a portion of the nucleotide sequences of each of the 6 insulin-like growth factor (IGF) binding proteins (IGFBPs) in horses and describe patterns of messenger RNA (mRNA) and protein expression for IGFBPs in normal equine tendons. Methods: 7 horses. Methods: Total RNA was extracted from the tensile region of normal superficial digital flexor tendons and reverse transcribed into complimentary DNA (cDNA). The cDNA was amplified via PCR, and products representing portions of each IGFBP were cloned and sequenced. Nucleotide sequences were used to deduce the amino acid sequences, and both ...
Dahlgren LA, Brower-Toland BD, Nixon AJ.To clone the 5' end of type III collagen and describe its pattern of mRNA and protein expression in normal and healing tendons in horses. Methods: 14 healthy adult horses. Methods: The tensile region of collagenase-injured superficial digital flexor tendons was harvested at intervals from 1 to 24 weeks after injury. Total RNA was reverse-transcribed into cDNA for cloning and sequencing of type III collagen. Equine-specific nucleic acid probes were developed and used for northern blot analysis and in situ hybridization. Type III collagen protein and cyanogen bromide-cleaved collagen peptides we...
Regis WC, Fattori J, Santoro MM, Jamin M, Ramos CH.The work in the literature on apomyoglobin is almost equally divided between horse and sperm whale myoglobins. The two proteins share high homology, show similar folding behavior, and it is often assumed that all folding phenomena found with one protein will also be found with the other. We report data at equilibrium showing that horse myoglobin was 2.1 kcal/mol less stable than sperm whale myoglobin at pH 5.0, and aggregated at high concentrations as measured by gel filtration and analytical ultracentrifugation experiments. The higher stability of sperm whale myoglobin was identified for both...
Grignard E, Morin J, Vernet P, Drevet JR.We report here on the cloning of cDNAs coding bovine and equine orthologs of mouse epididymis-restricted and sperm-bound glutathione peroxidase 5 (GPX5), a selenium-independent member of the multigenic GPX family in mammals. The complete sequence of bovine GPX5 as well as a partial sequence of the equine GPX5 were characterized, conceptually translated and aligned with other known mammalian GPX5 proteins. Using Northern blotting assays, we show that the level of expression of GPX5 is high in bovine but low in equine and that in both species the regionalization of GPX5 expression in epididymis ...
Bhuyan AK, Rao DK, Prabhu NP.Proteins meet with the stipulations of Levinthal. Two test tube variants of ferrocytochrome c (ferrocyt c) whose thermodynamic stabilities are vastly different refold to the same global minimum under a given final native condition, and they do so quickly at rates that do not reflect a strong dependence on the thermodynamic driving force. The transition-state ensemble is more unfolded-like, and the folding barrier offered is energetically sizable. The experiments involve neutral- (pH 7) and alkaline ferrocyt c pH (12.7), whose aqueous stabilities are 18 (+/-0.3) and 3 (+/-0.5) kcal mol(-)(1), r...
Albrecht RA, Kim SK, O'Callaghan DJ.The equine herpesvirus 1 (EHV-1) EICP27 protein cooperates with either the immediate-early (IE) or the EICP0 protein to synergistically trans-activate viral promoters. GST-pulldown and co-immunoprecipitation assays revealed that the EICP27 protein's cooperation with the IE or the EICP0 protein involves its physical interaction with these viral proteins. In the case of the IE-EICP27 protein interaction, IE residues 424 to 826 and EICP27 residues 41 to 206 harbor the interactive domains. Electrophoretic mobility shift assays (EMSA) suggested that the EICP27 protein is not a sequence-specific DNA...
Legardinier S, Duonor-Cérutti M, Devauchelle G, Combarnous Y, Cahoreau C.Equine luteinizing hormone (eLH) and chorionic gonadotropin (eCG) are composed of identical alpha and beta polypeptide chains, but eCG subunits are much more heavily glycosylated and sialylated. Consequently, eCG exhibits a much longer half-life than eLH in blood. Recombinant eLH/CG, expressed in Sf9 and Mimic insect cells, were compared with one another and to the natural hormones eCG and eLH. Mimic cells are stably-transformed Sf9 cells, expressing five mammalian genes encoding glycosyltransferases involved in the synthesis of complex N-carbohydrate chains. Recombinant eLH/CG expressed in Mi...
Hornyák A, Dénes B, Szeredi L, Dencsö L, Rusvai M.Two monoclonal antibodies against the Bucyrus strain of equine arteritis virus (EAV) were produced, and according to immunoperoxidase reaction following Western blot of electrophoresed EAV structural proteins, they recognized the nucleocapsid (N) protein antigen (14-kDa protein). Besides reacting with the blotted polypeptide, the antibodies of the two clones (designated 1H1 and 4G6) selected from 576 have shown high affinity and specificity to intracellular virus antigen as well. Both antibodies reacted with the representatives of the different subtypes of equine arteritis virus providing a su...
Gutmann S, Zawatzky R, Müller M.Interferon-gamma (IFN-gamma) is a key cytokine in cell-mediated immunity. To measure IFN-gamma production of equine lymphocytes (eqIFN-gamma), we developed a quantitative ELISA. Monoclonal antibodies (mAb) were produced against bacterially derived eqIFN-gamma. The mAbs recognised recombinant and lymphocyte-derived eqIFN-gamma in ELISA, Western blotting, as well as flow cytometric and microscopic analysis. In contrast to bacterially derived material, mammalian and insect cell-derived eqIFN-gamma was biologically active but could be neutralised by one of the monoclonal antibodies. Unexpectedly, ...
Arai K, Misumi K, Carter SD, Shinbara S, Fujiki M, Sakamoto H.Cartilage oligomeric matrix protein (COMP) is abundant within cartilage; its turnover and/or degradation have been investigated in various equine joint diseases and it has been suggested that COMP fragmentation might be useful for monitoring such conditions. Objective: To determine whether COMP metabolism is compromised in equine osteoarthritis (OA) and whether COMP degradation is a useful joint marker representing cartilage destruction. Objective: A monoclonal antibody (mAb) with a higher affinity for degraded COMP allows discrimination of diseased joints by quantifying COMP levels and fragme...
Krishnan A, Wilson A, Sturgeon J, Siedlecki CA, Vogler EA.A systematic study of water-air (liquid-vapor, LV) interfacial tension gamma(lv) of blood plasma and serum derived from four different mammalian species (human, bovine, ovine and equine) reveals nearly identical concentration-dependence (dgamma(lv)/dlnC(B); where C(B) is plasma/serum dilution expressed in v/v concentration units). Comparison of results to a previously-published survey of purified human-blood proteins further reveals that dgamma(lv)/dlnC(B) of plasma and serum is surprisingly similar to that of purified protein constituents. It is thus concluded that any combination of blood-pr...
León G, Lomonte B, Gutiérrez JM.Early adverse reactions occur in a number of patients treated with heterologous antivenoms and have been associated with anticomplementary activity (ACA). In order to reduce the ACA of equine whole IgG antivenoms produced by caprylic acid fractionation, three different fractionation protocols were compared: (a) routine caprylic acid fractionation; (b) caprylic acid fractionation followed by beta-propiolactone treatment; and (c) caprylic acid fractionation followed by ion-exchange chromatography using a quaternary ammonium membrane. The three protocols yielded products with similar physicochemi...
Malisauskas M, Ostman J, Darinskas A, Zamotin V, Liutkevicius E, Lundgren E, Morozova-Roche LA.In amyloid diseases, it is not evident which protein aggregates induce cell death via specific molecular mechanisms and which cause damage because of their mass accumulation and mechanical properties. We showed that equine lysozyme assembles into soluble amyloid oligomers and protofilaments at pH 2.0 and 4.5, 57 degrees C. They bind thioflavin-T and Congo red similar to common amyloid structures, and their morphology was monitored by atomic force microscopy. Molecular volume evaluation from microscopic measurements allowed us to identify distinct types of oligomers, ranging from tetramer to oc...
Karlström A, Jacobsson K, Flock M, Flock JI, Guss B.Strangles is a serious disease in horses caused by Streptococcus equi subspecies equi. In this study, genes encoding putative extracellular proteins in this subspecies have been identified using signal sequence phage display. Among these, one showed similarities to the SclB protein, a member of the collagen-like proteins of Streptococcus pyogenes. The novel gene denoted sclC encodes a protein, SclC, of 302 amino acids, containing typical features found in cell wall-anchored proteins in Gram-positive bacteria. Based on similarities to the S. pyogenes collagen-like proteins the mature SclC prote...
Sayasith K, Bouchard N, Boerboom D, Brown KA, Doré M, Sirois J.Ovulation is accompanied by a marked infiltration of leukocytes into thecal layers after the gonadotropin surge. P-selectin is known to play a critical role in the initial steps of leukocyte recruitment from the bloodstream during inflammation. Thus, the objective was to investigate the potential regulation of P-selectin by gonadotropins in equine preovulatory follicles. The full-length equine P-selectin cDNA was cloned by a combination of reverse transcription-polymerase chain reaction (RT-PCR) and 5'- and 3'-rapid amplification of cDNA ends. Results showed that equine P-selectin cDNA encodes...
O'Rourke JP, Olsen JC, Bunnell BA.Gene transfer into hematopoietic cells may allow correction of a variety of hematopoietic and metabolic disorders. Optimized HIV-1 based lentiviral vectors have been developed for improved gene transfer and transgene expression into hematopoietic cells. However, the use of HIV-1 based vectors for human gene therapy may be limited due to ethical and biosafety issues. We report that vectors based on the non-primate equine infectious anemia virus (EIAV) transduce a variety of human hematopoietic cell lines and primary blood cells. To investigate optimization of gene expression in hematopoietic ce...
Chan CP, Wan TS, Watkins KL, Pelsers MM, Van der Voort D, Tang FP, Lam KH, Mill J, Yuan Y, Lehmann M, Hempel A, Sanderson JE, Glatz JF, Renneberg R.Fatty acid-binding protein (FABP) holds promise for early detection of tissue injury. This small protein (15kD) appears earlier in the blood than large proteins after cell damage. Combined its characteristics of high concentration tissue contents and low normal plasma values provide the possibility of a rapid rise above the respective reference values, and thus an early indication of the appearance of tissue injury. A general review was presented on the current status of different types of FABP for the detection of tissue injury in patients with myocardial injury, brain injury and also in athl...
Flaminio MJ, Yen A, Antczak DF.Observations in early equine pregnancy clearly reveal maternal immune recognition of and response to the presence of the conceptus. Nevertheless, both maternal cellular and humoral responses appear ineffective in destroying the developing placenta and fetus in early pregnancy. Our previous studies had shown that the pre-conditioned medium generated from the culture of equine invasive trophoblast inhibited mitogen-induced lymphocyte proliferation and the expression of cytokine messenger RNA in vitro. Those findings also suggested that lymphocytes might have been halted in the G0/G1 phase of the...
O'Donovan LH, McMonagle EL, Taylor S, Argyle DJ, Nicolson L.Interleukin 18 (IL-18) is a cytokine capable of induction of IFNgamma, granulocyte monocyte-colony stimulating factor (GM-CSF), TNFalpha and IL-1 in immunocompetent cells. Equine and feline plasmid vectors expressing pro-IL-18, mature IL-18 and IL-18 fused to a synthetic signal sequence from human IL-1beta receptor antagonist protein (ILRAP), ILRAP-IL-18, have been generated. In vitro protein expression of these constructs was compared by Western blot analysis. These data demonstrated that ILRAP-IL-18 protein was secreted readily from transfected chinese hamster ovary (CHO) cells. A simple bio...
Cauchard J, Sevin C, Ballet JJ, Taouji S.The aim of this study was to evaluate serum IgG antibody levels and opsonizing activity in foals from pregnant mares immunized with either proteins from an R. equi strain containing virulence-associated protein A (VapA), an immunodominant surface-expressed lipoprotein encoded by a virulence plasmid crucial for virulence in foals, or a whole killed virulent R. equi preparation. Forty-eight pregnant mares were distributed into three groups, i.e. 24 immunized with R. equi VapA protein antigen associated with a water-based nanoparticle adjuvant (Montanide IMS 3012), 8 immunized with whole killed R...
Mancheño JM, Jayne S, Kerfelec B, Chapus C, Crenon I, Hermoso JA.Horse pancreatic lipase-related proteins PLRP1 and PLRP2 are produced by the pancreas together with pancreatic lipase (PL). Sequence-comparison analyses reveal that the three proteins possess the same two-domain organization: an N-terminal catalytic domain and a C-terminal domain, which in PL is involved in colipase binding. Nevertheless, despite the high level of sequence identity found, they exhibit distinct enzymatic properties. The intrinsic sensitivity of the peptide bond between Ser245 and Thr246 within the flap region of PLRP2 to proteolytic cleavage probably complicates PLRP2 crystalli...
Olsman AF, Huurdeman CM, Jansen WL, Haaksma J, Sloet van Oldruitenborgh-Oosterbaan MM, Beynen AC.In a cross-over study with six mature horses, the effect of iso-energetic replacement of dietary glucose by beet pulp on macronutrient digestibility, nitrogen metabolism and mineral absorption was studied. The test ration contained 25% beet pulp in the total dietary dry matter. Beet pulp feeding significantly lowered crude fat and non-structural carbohydrate digestibility, but had no significant effect on digestibility of other macronutrients, faecal and urinary nitrogen excretion and the faecal to urinary nitrogen excretion quotient. However, on the beet pulp diet, plasma ammonia and creatini...
Miller I, Friedlein A, Tsangaris G, Maris A, Fountoulakis M, Gemeiner M.We constructed a reference two-dimensional protein map for horse (Equus caballus) serum. The serum proteins were separated by two-dimensional electrophoresis (2-DE); 29 different gene products were identified. Proteins represented by 25 spots/spot groups were identified by tandem nanoelectrospray mass spectrometry (MS), four by matrix-assisted laser desorption ionization time-of-flight (TOF) MS and one was sequenced by TOF-TOF technology. The identities of four proteins were deduced by similarity to the human plasma protein database. In selected cases, i.e. the immunoglobulins, immunoblotting ...
Fock U, Jockusch BM, Schubert WD, Hinssen H.The actin-binding protein gelsolin is highly conserved in vertebrates and exists in two isoforms, a cytoplasmic and an extracellular variant, generated by alternative splicing. In mammals, these isoforms differ only by an N-terminal extension in plasma gelsolin, a short sequence of up to 25 amino acids. Cells and tissues may contain both variants, as plasma gelsolin is secreted by many cell types. The tertiary structure of equine plasma gelsolin has been elucidated, but without any information on the N-terminal extension. In this paper, we present topographical data on the N-terminal extension...
Corda M, Era B, Fais A, Casu M.The potentiality of xenon's sensitivity to its local magnetic environment is thoroughly investigated to probe internal structural differences between pig and horse metmyoglobin (MMb). These MMb's differ by 14 amino acids. One of these, Ile142 in horse MMb, is located in the proximal cavity, which is the xenon-binding site in horse MMb, and is replaced by Met142 in pig MMb. Specific and non-specific xenon-protein interactions are investigated here by 129Xe NMR chemical shifts and relaxation rate in aqueous solutions of pig MMb as a function of the xenon and protein concentrations. The results a...
Martinez I, Barrera JC, Rodriguez LL, Wertz GW.Vesicular stomatitis virus (VSV) is the most common cause of vesicular disease outbreaks in livestock throughout the Western Hemisphere. Two major serotypes, Indiana and New Jersey, cause epidemic disease in pigs, cattle, and horses. We generated recombinant viruses derived from the Indiana serotype genome that were engineered to contain and express: (1) a single copy of the glycoprotein gene from the Indiana serotype (VSIV-GI); (2) a single copy of the glycoprotein gene from the New Jersey serotype (VSIV-GNJ); or (3) two copies of the glycoprotein gene, one from each of the two major VSV sero...
Luo J, Bruice TC.Molecular dynamics and cross-correlation analysis of the horse liver alcohol dehydrogenase HLADH.NAD(+).PhCH(2)O(-) complex has established anticorrelated motions between the NAD(+)-binding domain and other portions of the enzyme. Four pairs of anticorrelated interactions are (i and ii) cofactor-binding domain: C(alpha) of V292 and the CG1 of V203 with C7 of PhCH(2)O(-); (iii) cofactor-binding domain: amide carbonyl oxygen of I318 with amide N of H67; and (iv) cofactor domain: C(alpha) of T178 with carbonyl oxygen of L141. The average distances between pairs are 9.2 A for i, 8.2 A for ii, 14.7...
Miranda G, Mahé MF, Leroux C, Martin P.The principal components of the protein fraction in pony mare's milk have been successfully identified and partially characterized using proteomic tools. Skimmed pony mare's milk was fractionated by either reversed phase-high-performance liquid chromatography (RP-HPLC) on a C4 column or a bi-dimensional separation technique coupling RP-HPLC in the first dimension and sodium dodecyl sulfate-polyacrylamide electrophoresis (SDS-PAGE) in the second dimension (two-dimensional RP-HPLC/SDS-PAGE). The fractions thus obtained were analyzed by Edman N-terminal microsequencing and mass determination, wit...
Pepin K, Momose F, Ishida N, Nagata K.Heat shock protein 90 (Hsp90), a molecular chaperone, is ubiquitous and involved in numerous cellular processes. To contribute to the relatively small collection of vertebrate Hsp90 sequences in the gene data bank, we cloned and sequenced horse (Equus caballus) Hsp90 alpha and beta cDNAs. This enabled identification of horse-specific primers for development of a convenient PCR-based method that could monitor horse stress tolerance. We analyzed the sequence data comparatively and phylogenetically with other Hsp90 cDNA sequences, and identified vertebrate-specific and isoform-specific conserved ...
Westermann CM, Dorland L, van Diggelen OP, Schoonderwoerd K, Bierau J, Waterham HR, van der Kolk JH.Earlier research on ten horses suffering from the frequently fatal disorder atypical myopathy showed that MADD (multiple acyl-CoA dehydrogenase deficiency) is the biochemical derangement behind atypical myopathy. From five horses that died as a result of this disease and seven healthy control horses, urine and plasma were collected ante mortem and muscle biopsies were obtained immediately post-mortem (2 patients and 7 control horses), to analyse creatine, purine and carbohydrate metabolism as well as oxidative phosphorylation. In patients, the mean creatine concentration in urine was increased...
Rapacz-Leonard A, Leonard M, Chmielewska-Krzesińska M, Paździor-Czapula K, Janowski T.Major histocompatibility protein class I (MHC-I) is believed to be expressed in the horse allantochorion only in limited areas at limited times. However, its expression has only been investigated in early pregnancy with non-quantitative techniques that cannot reliably detect small amounts of protein. To quantify the relative expression of MHC-I in the allantochorion and endometrium during days 90-240 of pregnancy (PREG), parturition with physiological delivery of fetal membranes (PHYS), and parturition with retention of these membranes (FMR). Also, to visualize protein expression and determine...
Theoret CL, Barber SM, Gordon JR.To describe the localization of immunoreactive transforming growth factor (TGF)-beta1 in both normal skin and full-thickness dermal wounds of the limb and the thorax of the horse. Methods: Six full-thickness excisional wounds were created on the lateral aspect of one metacarpal region and on the midthoracic area of each horse. Sequentially collected tissue specimens from wound margins were assessed for TGF-beta1 expression by immunohistochemistry. Methods: Four horses (2 to 4 years of age). Methods: A neutralizing monoclonal anti-human TGF-beta1 antibody was used to detect the spatial expressi...
León G, Lomonte B, Gutiérrez JM.Early adverse reactions occur in a number of patients treated with heterologous antivenoms and have been associated with anticomplementary activity (ACA). In order to reduce the ACA of equine whole IgG antivenoms produced by caprylic acid fractionation, three different fractionation protocols were compared: (a) routine caprylic acid fractionation; (b) caprylic acid fractionation followed by beta-propiolactone treatment; and (c) caprylic acid fractionation followed by ion-exchange chromatography using a quaternary ammonium membrane. The three protocols yielded products with similar physicochemi...
Karagianni AE, Eaton SL, Kurian D, Cillán-Garcia E, Twynam-Perkins J, Raper A, Wishart TM, Pirie RS.Airway inflammation is highly prevalent in horses, with the majority of non-infectious cases being defined as equine asthma. Currently, cytological analysis of airway derived samples is the principal method of assessing lower airway inflammation. Samples can be obtained by tracheal wash (TW) or by lavage of the lower respiratory tract (bronchoalveolar lavage (BAL) fluid; BALF). Although BALF cytology carries significant diagnostic advantages over TW cytology for the diagnosis of equine asthma, sample acquisition is invasive, making it prohibitive for routine and sequential screening of airway ...
Orino K, Miura T, Muto S, Watanabe K.Canine and equine ferritin H and L subunit cDNA clones were obtained using reverse transcriptase-polymerase chain reaction (RT-PCR) and TA cloning from various tissues. Canine liver and spleen ferritin H subunit cDNA clones contained an open reading frame for the same 182-amino acid protein as that reported in canine brain ferritin H subunit cDNA although there were substitutions in the 3'-noncoding regions. Ferritin L subunit cDNA clones from canine liver, spleen, and kidney showed identical coding sequences encoding the 174-amino acid protein except for a single nucleotide substitution in ki...
Kitaoka Y, Endo Y, Mukai K, Aida H, Hiraga A, Takemasa T, Hatta H.To evaluate the effects of a single incremental exercise test (IET) on mRNA expression and protein content of monocarboxylate transporter (MCT) 1 and MCT4 in the gluteus medius muscle of Thoroughbreds. Methods: 12 Thoroughbreds (6 males and 6 females; age, 3 to 4 years). Methods: Horses underwent an IET before and after 18 weeks of high-intensity exercise training (HIT). Horses were exercised at 90% of maximal oxygen consumption for 3 minutes during the initial 10 weeks of HIT and 110% of maximal oxygen consumption for 3 minutes during the last 8 weeks of HIT. Gluteus medius muscle biopsy spec...
Lee GKC, Tessier L, Bienzle D.The Salivary Scavenger and Agglutinin (SALSA) protein is an innate immune protein with various alleged functions, including the regulation of inflammation and tissue remodeling. Transcriptomic studies of severe equine asthma (SEA) showed downregulation of the gene encoding SALSA in bronchial epithelium of asthmatic compared to non-asthmatic horses. This study aimed to characterize expression of SALSA in equine tissues by immunohistochemistry (IHC), corroborate potential differences in epithelial gene expression between asthmatic and non-asthmatic horses, and assess the structure of equine SALS...
Christmann U, Hite RD, Witonsky SG, Elvinger F, Werre SR, Thatcher CD, Tan RH, Buechner-Maxwell VA.Surfactant alterations are described in horses after exercise, anesthesia, and prolonged transport, in horses with recurrent airway obstruction, and in neonatal foals. The effect of horse age or bronchoalveolar lavage fluid (BALF) sample characteristics on surfactant is unknown. Objective: To evaluate surfactant phospholipid composition and function in healthy horses, and to investigate the influence of age and BALF sample characteristics on surfactant. Methods: Seventeen healthy horses 6-25 years of age maintained on pasture year-round. Methods: BALF was collected by standard procedures and w...
Li Y, Yao J, Chang M, Nikolic D, Yu L, Yager JD, Mesecar AD, van Breemen RB, Bolton JL.Catechol-O-methyltransferase (COMT) plays an important role in the inactivation of biologically active and toxic catechols. It has been shown that COMT is genetically polymorphic with a wild-type and variant form where a valine has been substituted with a methionine. Several, but not all, epidemiological studies have shown that women, homozygous with the variant form, have an increased risk of developing breast cancer. Previously, we showed that 4-hydroxyequilenin (4-OHEN), a cytotoxic/genotoxic equine catechol estrogen metabolite, is both a substrate of COMT and an irreversible inhibitor of t...
Manao G, Camici G, Stefani M, Berti A, Cappugi G, Liguri G, Nassi P, Ramponi G.Acylphosphatase was purified from horse muscle by a new procedure involving an affinity chromatography step and subsequent ion-exchange chromatography. This procedure was considerably milder than the preceding one, gave an overall yield of about 60% of activity and permitted isolation of three molecular forms with acylphosphatase activity. All these enzymatic forms are tightly bound to Sepharose 4B-linked anti-horse muscle acylphosphatase antibodies. Two of these forms (Ho1 and Ho3) are present in larger amounts: Ho1 corresponds to the enzyme purified according to the older procedure; this enz...
Ferreira LVO, Kamura BDC, Oliveira JPM, Chimenes ND, Carvalho M, Santos LAD, Dias-Melicio LA, Amorim RL, Amorim RM.Schwann cells (SCs) are essential for the regenerative processes of peripheral nerve injuries. However, their use in cell therapy is limited. In this context, several studies have demonstrated the ability of mesenchymal stem cells (MSCs) to transdifferentiate into Schwann-like cells (SLCs) using chemical protocols or co-culture with SCs. Here, we describe for the first time the in vitro transdifferentiation potential of MSCs derived from equine adipose tissue (AT) and equine bone marrow (BM) into SLCs using a practical method. In this study, the facial nerve of a horse was collected, cut into ...
Soma LR, Behrend E, Rudy J, Sweeney RW.The disposition of flunixin meglumine administered IV at a dosage of 1.1 mg/kg was described by a 2-compartment model; the alpha and beta half-lives (t1/2) were 0.61 and 1.5 hours, respectively. When administered IV at a rate of 2.2 mg/kg, the disposition was best described by a 3-compartment model, and the alpha, beta, and lambda t1/2 were 0.16, 1.52, and 6.00 hours, respectively. The zero-time plasma concentrations after flunixin meglumine was administered at 1.1 and 2.2 mg/kg were 9.3 +/- 0.76 and 21.5 +/- 7.4 mg/L, respectively. The bioavailability after oral administration of 1.1 mg/kg wa...
Welsch U, Schumacher U, Buchheim W, Schinko I, Jenness P, Patton S.A specific secretory product of the lactating mammary gland are triglyceride fat globules which are enveloped by a very complex membrane, the milk fat globule membrane (MFGM). In different mammalian species (man, rhesus monkey, horse, goat, sheep, cow, grey seal, camel, alpaka) the glycoproteins of this membrane have been analyzed by gel electrophoresis, Western blotting and lectin histochemistry. A remarkable intra- and interspecific variability of these glycoproteins has been detected pointing to so far unknown physiological adaptions, which may play a role in the intestine of the new born. ...
Wang W, Mukai K, Takahashi K, Ohmura H, Takahashi T, Hatta H, Kitaoka Y.The aim of this study was to investigate effects of short-term hypoxic training on lactate metabolism in the gluteus medius muscle of Thoroughbreds. Using crossover design (3 months washout), eight Thoroughbred horses were trained for 2 weeks in normoxia (F O = 21%) and hypoxia (F O = 18%) each. They ran at 95% maximal oxygen consumption (V̇O ) on a treadmill inclined at 6% for 2 min (3 days/week) measured under normoxia. Before and after each training period, all horses were subjected to an incremental exercise test (IET) under normoxia. Following the 2-week trainings, V̇O in IET ...
Fouchécourt S, Charpigny G, Reinaud P, Dumont P, Dacheux JL.Prostaglandin D2 synthase (PGDS) is a major epididymal secretory protein in several species. We quantified PGDS in ram and bull semen using a specific antiserum. Strong variations in PGDS concentration existed between animals. In the bull, the highest concentrations were found preferentially in animals with normal or high fertility, as was previously suggested. However, low concentrations were found in males with all ranges of fertility, suggesting that the function of PGDS either is not necessary for male fertility or can be assumed by other proteins when its concentration is low. In the ram ...
Mobasheri A, Critchlow K, Clegg PD, Carter SD, Canessa CM.Equine laminitis is a multifactorial connective tissue disorder with major implications for the welfare of horses. There are few published studies on phenotypic markers for identification of equine laminar keratinocytes using immunohistochemical techniques. Objective: To establish whether the epithelial sodium channel (ENaC) and the GLUT1 and GLUT4 facilitative glucose transporters may be used as phenotypic markers for identification of equine laminar keratinocytes using immunohistochemical techniques to monitor changes in the keratinocyte population in laminitis. Methods: Histology and immuno...
Stewart F, Charleston B, Crossett B, Barker PJ, Allen WR.An apparently unique protein produced in large quantities by the endometrium of the mare which adheres to, or is incorporated into, the acellular capsule that surrounds the equine conceptus in early pregnancy, has been characterized and partially sequenced. It has a molecular mass of approximately 18 kDa on SDS-PAGE gels and is nonglycosylated as assessed by a sensitive carbohydrate detection kit. Comparison of its first 24 amino-terminal amino acids with all entries in the databases failed to show any significant identity with any other protein sequence. Secretion of the protein appears to be...
Okada A, Suganuma S, Badr Y, Omatsu T, Mizutani T, Ohya K, Fukushi H.VP22 is a major tegument protein of equine herpesvirus type 1 (EHV-1). In the present study, we examined functions of VP22 in EHV-1 replication by viral protein expression analyses in cells infected with the VP22-deficient virus. The expressions of several viral proteins in the cells infected with the VP22-deficient virus were lower than those in the cells infected with the parent virus. One of the weakly expressed proteins was identified as ICP4, which is a major regulatory protein encoded by an immediate early gene of EHV-1. A real-time PCR analysis showed that the mRNA expression of ICP4 wa...
Koepf EK, Hewitt J, Vo H, Macgillivray RT, Burtnick LD.We have generated and characterized the cDNA from equine smooth muscle that encodes gelsolin, an actin-modulating protein. Overlapping cDNA clones synthesized by the reverse transcriptase/polymerase chain reaction and clones isolated from a horse genomic library provided the complete primary structure for the intracellular isoform of gelsolin, while cDNA complemented with protein sequence data produced the full-length primary transcript of the gelsolin isoform found circulating in equine plasma. The deduced amino acid sequences of the intracellular and secreted versions of equine gelsolin infe...
Sayasith K, Bouchard N, Doré M, Sirois J.The progressive rise in gonadotropins prior to ovulation triggers a marked increase in intrafollicular levels of prostaglandin F(2alpha)(PGF(2alpha)), which is known to interact with PGF(2alpha) receptor (FP). Little is known about the regulation of FP during ovulation. This study was undertaken to characterize the equine FP and its gonadotropin-dependent regulation in preovulatory follicles prior to ovulation. The full-length equine FP encodes a 366-amino acid protein that is 82-93% homologous to other species. Using semi-quantitative RT-PCR/Southern blot, we showed that FP mRNA expression wa...
D'Silva C.Equine liver glutathione S-transferase has been shown to consist of two identical subunits of apparent Mr 25,500 and a pl of 8.9. Kinetic data at pH 6.5 with 1-chloro-2,4-dinitrobenzene as a substrate suggests a random rapid-equilibrium mechanism, which is supported by inhibition studies using glutathione analogues. S-(p-Bromobenzyl)glutathione and the corresponding N alpha-, CGlu- and CGly-substituted derivatives have been found, at pH 6.5, to be linear competitive inhibitors, with respect to GSH, of glutathione transferase. N-Acetylation of S-(p-bromobenzyl)glutathione decreases binding by 1...
Amit T, Dibner C, Barkey RJ.The present study was undertaken to identify and characterize the diversity and species distribution of soluble prolactin binding-protein (PRL-BP) and growth hormone-binding protein (PRL-BP) in mammalian milk. We previously divided mammalian serum GH-BP into four main groups and identified a GH-BP with shared lactogenic/somatogenic properties in rabbit, horse, dog, pig and cat (Type III species). Here we describe PRL-BP in milk of Type III species and show it is relatively conserved within the group, having similar characteristics in terms of binding affinity for hGH (0.74-5.5 x 10(10) M(-1)),...
Calvete JJ, Reinert M, Sanz L, Töpfer-Petersen E.Boar and stallion seminal plasmas were fractionated using affinity chromatography on heparin-Sepharose. In both species, among other proteins, the heparin-binding (H+) and non-heparin-binding (H-) fractions each contained glycoforms of either porcine PSP-I or equine HSP-1 and HSP-2. However, porcine H+/PSP-I eluted as a monomeric protein, whereas H-/PSP-I formed a heterodimer with PSP-II, another major seminal plasma protein. On the other hand, the stallion proteins H+/HSP-1 and H+/HSP-2 eluted together as an aggregate of relative molecular mass (M(r)) 90,000, whereas H-/HSP-1 and H-/HSP-2 elu...
Park DH, Plapp BV.The E and S isoenzymes of horse liver alcohol dehydrogenase differ by 10 amino acid residues, but only the S isoenzyme is active on 3 beta-hydroxysteroids. This functional difference was correlated to the differences in structures of the isoenzymes by characterizing a series of chimeric enzymes, which could represent intermediates in the evolution of catalytic activity. Deletion of Asp-115 from the E isoenzyme created the E/D115 delta enzyme that is active on steroids. The deletion alters the substrate binding pocket by moving Leu-116, which sterically hinders binding of steroids in the E isoe...
Elroy NN, Rogers J, Mafi GG, VanOverbeke DL, Hartson SD, Ramanathan R.Our objectives were to determine the non-enzymatic metmyoglobin reduction properties of bovine, porcine, and equine myoglobins and to characterize the effects of pre-incubation of 4-hydroxy-2-nonenal (HNE) with myoglobins on non-enzymatic metmyoglobin reduction in vitro. Purified bovine, porcine, and equine metmyoglobins (0.05 mM) were reduced at pH 5.6 and 7.4 in the presence or absence of HNE. Rates of metmyoglobin reduction were monitored by spectrophotometry, and myoglobin adducts were characterized by high-resolution mass-spectrometry. Results showed that the species origins of individual...
Saman E, Breugelmans K, Heyndrickx L, Merregaert J.The genome of equine infectious anemia virus (EIAV) contains several small open reading frames (ORFs), the importance of which in the development of the virus is not clear. We investigated the possibility that the largest of these ORFs (ORF S3) is expressed during the course of the viral infection. The ORF S3 information was expressed in Escherichia coli, and the antigen was used to raise monospecific antiserum. A 20-kDa protein expressed in cells producing EIAV was identified as the gene product of ORF S3. Furthermore, sera from EIAV-infected animals specifically recognized this protein, indi...
Pirhonen A, Linnala-Kankkunen A, Mënpää PH.P1 protamines isolated from ejaculated human, stallion, bull, boar and ram spermatozoa and P2 protamines from human and stallion spermatozoa were subjected, after alkaline phosphatase treatment, to in vitro phosphorylation reactions using cAMP-dependent protein kinase (PKA) and protein kinase C (PKC). All P1 protamines were phosphorylated by PKA, whereas P2 protamines were phosphorylated only by PKC. In addition, human, stallion and boar, but not bull and ram, P1 protamines were phosphorylated by PKC. After phosphoamino acid analysis, the protamines showing positive signals for phosphoserine (...
Turki I, Hammami A, Kharmachi H, Mousli M.Human and equine rabies immunoglobulins are currently available for passive immunization against rabies. However, these are hampered by the limited supply and some drawbacks. Advances in antibody engineering have led to overcome issues of clinical applications and to improve the protective efficacy. In the present study, we report the generation of a trivalent single-chain Fv (scFv50AD1-Fd), that recognizes the rabies virus glycoprotein, genetically fused to the trimerization domain of the bacteriophage T4 fibritin, termed 'foldon' (Fd). scFv50AD1-Fd was expressed as soluble recombinant protei...
