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.
Weidmeyer CE, Solter PF.The Incstar(R) SPQ II human haptoglobin (Hpt) (Incstar Corporation, Stillwater, MN) immunoturbidimetric assay was validated for the determination of serum and plasma Hpt concentrations in dogs and horses. The anti-human Hpt antiserum supplied with the assay, displayed monospecificity to both dog and horse serum Hpt by immunoelectrophoresis and Western blotting techniques. The automated immunoturbidimetric assay results correlated well with the cyanmethemoglobin binding assay (r=0.953 for canine serum and r=0.941 for equine serum), and had excellent precision at both high and low serum Hpt conc...
Thomas PG, Ignotz GG, Ball BA, Brinsko SP, Currie WB.Adhesion of equine spermatozoa to homologous oviduct epithelial cells (OEC) in vitro results in specific changes in spermatozoa and OEC function. To test the hypothesis that adhesion of spermatozoa affects protein synthesis and secretion by OEC, the following treatment groups were established in culture: OEC with culture medium only; control spermatozoa in culture medium only; OEC in coculture with spermatozoa; and OEC and spermatozoa in coculture, but physically separated by a microporous membrane. The experiment was replicated within each of 4 ejaculates from 3 stallions. De novo protein sec...
Bell K, Arthur H, Breen M.Eleven apparent mutations of the equine plasma transferrin and esterase gene (10 in TF and one in ES) were found in an analysis of approximately 240,000 thoroughbred horses. Eight of the transferrin mutations produced variants not previously recognized in horses. In the two remaining transferrin mutations and the esterase mutation, reduced plasma concentrations of the proteins were demonstrated by immunological techniques and together with the family data indicated the existence of 'null' alleles.
Dillon AM, Heath MF.Protein tyrosine phosphorylation (PTP) in thrombin- and platelet-activating factor (PAF)-stimulated equine platelet activation was investigated in the absence and presence of 2 protein tyrosine kinase inhibitors (PTKIs), methyl 2,5-dihydroxycinnamate (MDHC) and genistein. Washed equine platelets aggregated irreversibly in response to thrombin or PAF in an agonist concentration dependent fashion. MDHC produced an MDHC concentration and time dependent inhibitory effect on rate and extent of thrombin- and PAF-induced aggregations, whereas the effect of genistein on the same parameters was only ge...
McConaghy FF, Hodgson DR, Evans DL, Rose RJ.Significant alterations in plasma electrolyte concentrations have been reported in horses following prolonged exercise, resulting from loss of hypertonic sweat. Sweat was collected from 10 horses undergoing a 10 week training programme; 5 at moderate intensity, to speeds of 10 m/s and 5 at low intensity, to speeds of 5 m/s. Sweat was collected from 2 sites in response to a submaximal exercise test (30 min at 50% VO2max and during an adrenaline infusion (dose mean +/- s.d.; 0.3 +/- 0.05 g/kg over 30 min). Sweat samples were analysed for sodium, chloride, potassium, protein, magnesium, calcium a...
Cardier J, Romano E, Soyano A.Iron and ferritin impair a variety of immunological functions. To evaluate the effect of ferritin iron content on rat lymphocyte proliferative response, isoferritins that differ in their iron content and isoelectric point (pI) were isolated from iron overload rat livers by ultracentrifugation (isoferritins with high iron content and low pI) or crystallization (isoferritins with low iron content and high pI) methods. Additionally, commercial horse splenic ferritin (with a lower pI and higher iron content than rat isoferritins) was also tested. Proliferative response to Con A was decreased in a ...
Yee S, Peyton DH.The redistribution of the initially-formed myoglobin heme-insertion isomers from the initially formed 50/50 mixture to the equilibrium ratio of 90/10 has long been assumed to occur by one of two mechanisms, both of which require the rupture of the heme iron-protein bond (La Mar, G.N., Toi, H. and Krishnamoorthi, K. (1984) J. Am. Chem. Soc. 106, 6395-6401). In this study we compared the use of nuclear magnetic resonance and optical spectroscopic techniques as methods for studying the reorientation of heme within myoglobin. We found that kinetics determinations of the heme insertion isomer redis...
Vagnoni KE, Ginther OJ, Lunn DP.Chorionic girdle cells are a highly invasive subpopulation of trophoblast cells of the equine conceptus. By Day 35 (Day 0 = day of ovulation), cells of the chorionic girdle adhere to the uterine epithelium and begin to invade the endometrial wall. Invasive cells must attach to extracellular matrix proteins, secrete proteinases capable of degrading matrix, and migrate through the degraded matrix; invasion is largely dependent on the proteinase activity of the cells. The objective, therefore, was to develop an in vitro system to examine the mechanisms of equine chorionic girdle cell invasion thr...
Satoh M, Fujinaga T, Okumura M, Hagio M.To measure the concentration of serum amyloid A (sAA) protein in horses, a sensitive and highly reproducible sandwich (ELISA) was established, using affinity purified SAA antibody. Results of the ELISA were found to have a high correlation (r = 0.95) with those of the single radial immunodiffusion test. Equine SAA concentration was measured by use of this ELISA. In clinically normal horses, the concentration of SAA was high immediately after birth to 2 weeks of age. After that, SAA concentration had periodic fluctuations in the range of approximately 1.0 to 30 micrograms/ml. Mean (+/- SD)) con...
Braun J, Hochi S, Oguri N, Sato K, Torres-Boggino F.Three experiments were conducted to evaluate the effect of different macromolecule components (egg yolk, skim milk, and BSA) in a widely employed extender for cryopreservation of horse semen. Spermatozoal motility (MOT) and the percentage of spermatozoa with an intact plasma membrane (IPM) were evaluated in frozen-thawed samples. In the first experiment (four Draft Horse stallions, four ejaculates each) a standard freezing extender containing 20% whole egg yolk was modified by replacing extender components (glucose-EDTA solution, 11% lactose solution) with an increasing volume of a skim milk d...
Griko YV, Freire E, Privalov G, van Dael H, Privalov PL.The energetics of the temperature-induced unfolding of equine lysozyme was studied calorimetrically and compared with that of two structurally homologous proteins: hen egg white lysozyme and alpha-lactalbumin. The structure of each of these proteins is characterized by the presence of a deep cleft that divides the molecule into two regions called the alpha and beta domains. In equine lysozyme and alpha-lactalbumin the latter domain specifically binds Ca2+. It is shown that, in contrast to hen egg white lysozyme in which the alpha and beta domains unfold as a single cooperative unit, in equine ...
Theodorakis JL, Armes LG, Margoliash E.beta-Thiopropionyl derivatives of horse cytochrome c singly modified at each of 18 different lysine epsilon-amino groups have been prepared using sulfosuccinimidyl-2-(biotinamido)ethyl-1,3-dithiopropionate and purified to homogeneity by high-pressure liquid chromatography. These derivatives were characterized by determination of: (i) the location of the modification; (ii) reduction potentials; (iii) visible and NMR spectra: and by (iv) measurement of electron transfer activity with cytochrome-c oxidase. No significant changes in structure were indicated, except for the ferric forms of the deri...
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...
Whalley JM, Love DN, Tewari D, Field HJ.A series of recombinant baculoviruses containing genes for glycoproteins C, D, H and L of equine herpesvirus 1 (EHV-1) have been constructed, and the EHV-1 products characterised by gel electrophoresis and immunoblotting. The EHV-1 glycoproteins expressed in insect cells were similar but not identical in apparent sizes to those expressed in EHV-1 infected mammalian cells. Each of the EHV-1 products was recognised by convalescent equine sera, indicating that they were all targets for an equine immune response. Mice immunised with baculovirus-expressed EHV-1 gD and gC acquired an enhanced abilit...
Crabb BS, Studdert MJ.A series of truncated equine herpesvirus 1 (EHV1) glycoprotein C (gC) molecules was examined for use as serodiagnostic antigens for EHV1 and EHV4. Small regions of EHV1 glycoprotein C, an immunodominant EHV1 glycoprotein, were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins using the bacterial expression vector pGEX-2T. Sera obtained from horses, including sera from specific-pathogen-free (SPF) foals, following exposure to either EHV1, EHV4 or both viruses were used. Several of the fusion proteins were shown to encompass EHV1 specific epitopes while others enco...
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...
Calvete JJ, Mann K, Schäfer W, Sanz L, Reinert M, Nessau S, Raida M, Töpfer-Petersen E.We report the complete amino acid sequence of HSP-1, a major protein isolated from stallion seminal plasma or acid extracts of ejaculated spermatozoa. The protein consists of 121 amino acids organized in two types of homologous repeats arranged in the pattern AA'BB'. Each of the 13-15-residue A-type repeats contains two O-linked oligosaccharide chains. The B-type repeats span 44-47 amino acids each, are not glycosylated, and have the consensus pattern of the gelatin-binding fibronectin type-II module. This domain also occurs in the major bovine seminal plasma heparin-binding proteins PDC-109 (...
Collatos C, Barton MH, Prasse KW, Moore JN.Components of the coagulation and fibrinolytic cascades, prothrombin and activated partial thromboplastin times, endotoxin activity, and albumin concentration were measured in blood and peritoneal fluid from 20 healthy horses and from 153 horses with acute gastrointestinal tract diseases at admission. Overall, 77% (117/153) of affected horses survived to discharge from the hospital, and 85% (82/97) of horses discharged were reported to be normal 9 to 14 months later. Significant differences in hemostatic factors were more common in peritoneal fluid than in blood. Tissue plasminogen activator, ...
Marti E, Szalai G, Bucher K, Dobbelaere D, Gerber H, Lazary S.In order to isolate a part of the immunoglobulin E (IgE) heavy chain cDNA of the horse, primers have been designed based upon well conserved sequences in humans, sheep and rats. The PCR resulted in a 500 bp fragment which hybridised with a human IgE constant region probe. The fragment was cloned and sequenced and its derived protein sequence compared with the corresponding sequences in humans, sheep and mice. Most amino acids common to these three species are also shared by the horse.
Thomas PG, Ignotz GG, Ball BA, Miller PG, Brinsko SP, Currie B.Oviduct epithelial cells (OEC) increasingly are used to support embryonic development and to study gamete interactions with the female reproductive tract in vitro. This series of experiments was designed to characterize monolayers derived from oviduct epithelium. Epithelial cells harvested from the isthmus and ampulla of the oviducts of five estrous mares were cultured with or without the basal lamina extract, Matrigel. Within each group OEC were cultured in the presence of either estradiol-17 beta or a carrier control. All groups were subcultured three times. Epithelial cell morphology and fu...
Ochoa M, Bárcena J, de la Luna S, Melero JA, Douglas AR, Nieto A, Ortín J, Skehel JJ, Portela A.Characterization of the epitopes recognized by 21 monoclonal antibodies (MAbs) specific for the influenza A virus PA (13 MAbs) and PB2 (8 MAbs) polypeptides (Bárcena et al. (1994) J. Virol. 68, 6900-6909) raised against denatured polypeptides produced in E. coli is described. MAbs were characterized by: (1) competitive binding ELISAs; (2) mapping of the protein regions that specify their binding sites; and (3) analyses of their ability to recognize the corresponding viral protein in a number of viral isolates. Five and three non-overlapping antigenic areas were defined by the anti-PA and anti...
Dillon AM, Heath MF.The effects of the protein tyrosine kinase inhibitors tyrphostins B42 and B46 on equine platelet function and protein tyrosine phosphorylation (PTP) were assessed. Tyrphostins B42 and B46 (both at 100 microM concentration) produced significant inhibition of thrombin-stimulated equine platelet aggregation. The effect of tyrphostin B46 was also time-dependent. The same concentration of these inhibitors produced very little or no inhibition of platelet-activating factor (PAF)-induced aggregation. The effects of tyrphostins B42 and B46 on thrombin- and PAF-stimulated PTP were generally similar, al...
Wagner B, Radbruch A, Richards C, Leibold W.In order to define equine immunoglobulins (Igs) and to produce monoclonal reference Igs we fused equine peripheral blood mononuclear cells with X63-Ag8.653 non Ig producing murine myeloma cells. A total of 29 equine Ig producing equi-murine heterohybridomas were obtained, of which ten expressed equine Ig for more than 3 months. One of these heterohybridoma lines produced monoclonal IgM, an equine isotype which has not been available in monoclonal form before. Four lines secreted equine IgG of two distinct Ig heavy chain types as assessed by the molecular weight (MW), while the remaining five l...
Foygel K, Spector S, Chatterjee S, Kahn PC.Volume changes among the unfolded (U), native (N), and molten globule (MG) conformations of horse heart ferricytochrome c have been measured. U to N (pH 2 to pH 7) was determined in the absence of added salt to be -136 +/- 5 mL/mol protein. U to MG (pH 2, no added salt to pH 2, 0.5 M KCl) yielded + 100 +/- 6 mL/mol. MG to N was broken into two steps, N to NClx at pH 7 by addition of buffered KCl to buffered protein lacking added salt (NClx = N interacting with an unknown number, X, of chloride ions), and MG to NClx by jumping MG at pH 2 in 0.5 M KCl to pH7 at the same salt concentration. The d...
Telford EA, Watson MS, Aird HC, Perry J, Davison AJ.The complete DNA sequence of equine herpesvirus 2 (EHV-2) strain 86/67 was determined. The genome is 184,427 bp in size and has a base composition of 57.5% G + C. Unusually for a herpesvirus, about a third of the sequence distributed in several large blocks appears not to encode proteins. The 79 open reading frames that were identified as probably polypeptide-coding are predicted to encode 77 distinct proteins. Amino acid sequence comparisons confirmed that EHV-2 is a gamma-herpesvirus that is genetically collinear with herpesvirus saimiri (HVS; a gamma 2-herpesvirus) and Epstein-Barr virus (E...
Parraga ME, Carlson GP, Thurmond M.The present retrospective study was undertaken to determine the frequency of hypoproteinemia and hypoalbuminemia in horses with natural occurring severe liver disease. The study represents a review of case records and laboratory data of 84 horses presented with acute or chronic liver disease to the University of California Veterinary Medical Teaching Hospital between 1973 and 1991. Forty horses (48%) had serum protein concentrations above the maximum reference value (7.7 g/dL). The increase in serum protein concentration was associated with hyperglobulinemia (P = .00005, R2 = .80). Only 13% (1...
Sticker LS, Thompson DL, Fernandez JM, Bunting LD, DePew CL.Sixteen light horse mares were fed diets of bermudagrass hay and a corn/cottonseed hull-based supplement formulated to contain either 100% (control) or 50% (restricted) of the protein and(or) energy requirements for maintenance in a 2 x 2 factorial arrangement of treatments. Plasma IGF-I, prolactin, cortisol, triiodothyronine, and thyroxine were monitored for 33 d. On the 27th d, frequent blood samples were drawn throughout the day for the measurement of growth hormone (GH), and on the 29th d, an epinephrine challenge and an i.v. glucose tolerance test (IVGTT) were performed in the morning and...
Barsuren E, Namkhai B, Kong HS.The objective of this study was to assess differences in serum protein expression profiles of Przewalski's (Mongolian wild horse) and thoroughbred horses using proteome analysis. The serum proteins were separated by two-dimensional electrophoresis (2-DE) and five different gene products were identified. Proteins represented by the five spots were identified by matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS)/MS technology. The identities of all proteins were deduced based on their similarity to proteins in the human plasma protein database. Three pr...
Varhac R, Antalík M.A relation between pH-induced conformational transitions of horse heart ferricytochrome c and the kinetics of external ligand coordination to heme iron was investigated by optical spectroscopy, circular dichroism and viscometry. The dependencies of both the association, k (a), and dissociation rate constants of cyanide binding on pH were determined from kinetic measurements. The association rate constant exhibits a bell-shaped form of dependence on pH in the region where this protein unfolds. The maximum of the dependence of k (a) on pH is found to be coincident with the pK values of conformat...
Kydd JH, Case R, Minke J, Audonnet JC, Wagner B, Antczak DF.Cytotoxic T-lymphocytes (CTLs) are associated with protective immunity against disease caused by equid herpesvirus type 1 (EHV-1). However, the EHV-1 target proteins for CTLs are poorly defined. This limits the development of vaccine candidates designed to stimulate strong CTL immunity. Here, classical CTL assays using lymphocytes from horses of three defined MHC class I types that experienced natural infection with EHV-1 and a modified vaccinia virus construct containing an EHV-1 gene encoding the immediate-early (IE) protein are reported. Horses homozygous for the equine leukocyte antigen (E...
Viitanen M, Bird J, Maisi P, Smith R, Tulamo RM, May S.As a prerequisite for the identification of navicular disease markers, the concentrations of cartilage oligomeric matrix protein (COMP), total glycosaminoglycans (GAG), hyaluronan, metalloproteinases (MMP) 2 and 9 and total protein were measured in synovial fluid samples obtained from the distal interphalangeal joint (DIP), the metacarpophalangeal joint (MCP) and the navicular bursa of 24 horses. Mean GAG, COMP and total protein levels were significantly higher in the DIP joint and in the navicular bursa compared to the MCP joint. Hyaluronan content was lower. MMP -2 activity was present in al...
Greube A, Müller K, Töpfer-Petersen E, Herrmann A, Müller P.Seminal plasma of mammalians contains, among others, proteins that are characterized by the fibronectin (Fn) type II module. Our knowledge about the structure and the physiological function of seminal Fn type II proteins mainly originates from studies on PDC-109, the bovine representative of this protein family. The present work focuses on the equine protein SP-1/2 (also named HSP-1/2) with particular emphasis on its interaction with lipid membranes by employing the intrinsic protein fluorescence and a number of spin-labeled and fluorescent lipid analogues. The results indicate that the intera...
Canisso IF, Loux S, Scoggin KE, Squires EL, Troedsson MH, Ball BA.Characterisation of fetal fluids in healthy and disease states of pregnant mares can help to unravel the pathophysiology and to identify putative markers of disease. Thus, this study aimed to compare the protein composition of: (1) amniotic and allantoic fluids of healthy mares obtained immediately after euthanasia and (2) allantoic fluid harvested via centesis before and after experimental induction of placentitis via transcervical inoculation of Streptococcus equi ssp zooepidemicus in healthy mares. Fetal fluids were analysed with a high-throughput proteomic technique after in-gel digestion....
Mask TA, Schoenecker KA, Kane AJ, Ransom JI, Bruemmer JE.Immunocontraception with porcine ZP (pZP) can be an effective means of fertility control in feral horses. Previous studies suggest that antibodies produced after pZP vaccination may both inhibit fertilization and cause follicular dysgenesis. Zonastat-H, PZP-22, and SpayVac are three pZP vaccines proposed for use in horses. Although all these vaccines contain the pZP antigen, variations in antigen preparation and vaccine formulation lead to differences in antigenic properties among them. Likewise, despite numerous efficacy and safety studies of Zonastat-H and PZP-22, the contraceptive mechanism...
Wardle EN.Assessment of changes in activity of the reticuloendothelial system (RES), including the mesangial cells of the kidney, has been made by means of clearance studies of human aggregated gamma-globulin and of colloidal gold, during the course of horse serum sickness nephritis. RES blockade was found after protein loading and at the phase of circulating immune complexes. At other times RES activity was normal or increased. “Mesangial saturation” may have important implications for human nephritis.
Choi YH, Gibbons JR, Canesin HS, Hinrichs K.Prospective studies were conducted to help define procedural factors affecting in vitro embryo production via intracytoplasmic sperm injection (ICSI) of equine oocytes. In experiment 1, use of 10% fetal bovine serum as a protein source in embryo culture medium resulted in a higher blastocyst rate than did use of a combination of 3% fetal bovine serum, 3% equine preovulatory follicular fluid, and 4% human serum substitute (37% vs. 15%, respectively, P < 0.05). In experiment 2, the effect of zinc supplementation (0, 0.5, 1, or 1.5 μg/mL) during IVM was examined. There were no significant di...
Li J, Zhao Y, Mi J, Yi Z, Holyoak GR, Wu R, Wang Z, Zhu Y, Zeng S.Endometritis is a common disease in donkeys that causes economic losses to donkey farms and the common cause is bacterial infection. Uterine flush fluid proteomics has been used to study protein biomarkers associated with endometritis in mares. As a convenient diagnostic tool, serum proteomics has not been studied yet in equine species with endometritis. This study is aiming to evaluate the serum proteomics in jennies with and without endometritis and identify potential proteins as biomarker for endometritis diagnosis. Nine donkeys recruited into this study were diagnosed of bacterial (Escheri...
Carraway KL, Colton DG, Shin BC, Triplett RB.Bovine and equine erythrocytes have been studied by three different surface modification techniques to investigate the accessibility of the surface components to the external medium. Lactoperoxidase labeling of equine erythrocytes results in a significant labeling of only one membrane component, a 100 000-mol.wt polypeptide corresponding to the membrane-spanning Component III of human erythrocytes. The major sialoglycoprotein of the equine erythrocyte is not labeled. This is in contradistinction to the situation for human and bovine cells, where both components are labeled. The equine membrane...
Flowers CC, Flowers SP, Jennings SR, O'Callaghan DJ.Previous studies (C. C. Flowers and D. J. O'Callaghan, 1992, Virology 190, 307-315) employed peptide-specific antibodies to identify the product of the glycoprotein D (gD) gene of equine herpesvirus 1 strain Kentucky A (KyA). gD polypeptides of 55 and 58 kDa were detected in EHV-1-infected L-M cells, and the 58-kDa protein was observed in the membrane fraction of EHV-1 virions. In this report, the kinetics of synthesis and processing of gD polypeptides are described. One-hour pulse-labeling of EHV-1-infected L-M cells revealed that gD proteins are first detected at 6 hr after infection and tha...
Patterson SD, Bell K.Twelve equine protease inhibitory alleles, PiE, H, J, K, L2, O, P, Q, R, V, X, Z, have been characterized in terms of isoelectric point, molecular mass and inhibitory activity to bovine trypsin and chymotrypsin by ISO-DALT electrophoresis. Protein maps for 20 Pi alleles including those of the eight 'Thoroughbred' alleles (PiF, G, I, L, N, S1, S2, U) have now been determined. Five pairs of alleles, S1/S2, G/K, L/L2, P/R and U/Z, possessed varying numbers of common proteins ranging from one protein in the case of G/K and L/L2 to six in the case of U/Z. Based on these results and studies of the a...
Ramery E, Fievez L, Fraipont A, Bureau F, Lekeux P.The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses' airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immunohistochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cell...
Chen CH, Albers JJ.The abilities of apolipoprotein A-I species isolated from humans, horses, sheep, goats and rabbits to activate purified human lecithin-cholesterol acyltransferase and the enzyme from homologous plasmas and plasma of other mammalian species were compared. Each purified apolipoprotein A-I species was individually incorporated into phosphatidylcholine/cholesterol vesicles by the cholate dialysis method to form proteoliposome common substrates (apolipoprotein A-I/phosphatidylcholine/cholesterol molar ratio of 1:250:12.5) for the enzyme activity assay. All apolipoprotein A-I species tested had the ...
Tkachenko AG, Winston GW.Preincubation of horse liver alcohol dehydrogenase (HLADH) with the oxidative agent, tert-butyl hydroperoxide (tBOOH) results in a twofold stimulation of the ethanol dehydrogenase activity of this enzyme. This stimulation was dependent on tBOOH concentration up to 100 mM; above this concentration tBOOH did not further stimulate ethanol oxidation by HLADH. Active-site-directed reagents and classical ADH binary complexes were used to probe the possible mechanism of this activating effect. The rate and extent of stimulation by tBOOH is strongly reduced by binary complexes with NAD(+) or NADH, who...
Main AR.The kinetic and structural relationships of eight electrophoretically pure mammalian serum and liver serine carboxylesterases (CE) and cholinesterases (ChE) have been studied. Eight CE's and ChE's, which were fully resolved but only partially purified, provided additional information. Five of the electrophoretically pure esterases were monomeric, and of these, four belonged to a new and widely distributed class. These four monomeric esterases hydrolyzed choline esters, but at widely differing rates. Thus two were termed monomeric butyrylcholinesterases, mBuChE I and II, and two were monomeric ...
Cittadini A, Domínguez R, Sarriés MV, Pateiro M, Lorenzo JM.This study aimed to evaluate the effect of the total or partial replacement of NaCl by a commercial low-salt mixture Pansalt® (T1) or Kombu (L. ochroleuca) seaweed powder (T2), respectively, on the quality properties of dry-cured foal "cecina". Salt reformulation unaffected fat percentages, decreased (P < 0.001) moisture and ash contents, while protein amounts increased (P < 0.001) in the T2 batch. Considering the physicochemical variables, any significant differences were observed among batches, except for a*, water activity, and springiness values. T1 and T2 samples presented a si...
Depuydt E, Chiers K, Van Hecke L, Saunders J, Martens A, Pille F, Spaas JH.Injuries to equine tendons and ligaments are career-compromising, causing reduced performance and premature retirement. Promising treatment alternatives have been investigated in the field of mesenchymal stem cells (MSCs). In this study, the tissue adherence and protein expression of tenogenic primed mesenchymal stem cells (tpMSCs) after administration to ex vivo tendon and ligament explants is investigated. First, collagen type I (COL I) and smooth muscle actin (SMA) expression was assessed in cytospins prepared from native MSCs and tpMSCs. Second, equine superficial digital flexor tendon and...
Törneke MK, Ingvast-Larsson JC, Johansson JM, Appelgren LE.To determine pharmacokinetics of terbutaline in healthy horses and to relate serum terbutaline concentrations with the drug's pharmacodynamic effects. Methods: 6 healthy horses. Methods: Horses were given terbutaline i.v. (10 microg/kg of body weight) and, 1 week later, p.o. (100 microg/kg). Responses to drug administration (eg, heart rate and serum lactate concentration) were measured. Serum terbutaline concentration was measured by means of gas chromatography with mass spectrometry. Protein binding was determined in vitro. Results: Following i.v. administration, median maximum serum terbutal...
Klomkleaw W, Kasashima Y, Fuller GA, Kobayashi A, Yoshihara T, Oikawa MA, Izumisawa Y, Yamaguchi M.An anatomical study of horse lumbrical muscle (Lm) was carried out by light and electron microscopy in combination with immunochemical and cytochemical methods. Paraffin sections were subjected to haematoxylin and eosin (H & E) and Masson's trichrome staining for morphometric analysis. Paraffin sections were also used for immunostaining by anti-PGP 9.5 for reaction with nerve-protein associated-structures, anti-heat-shock protein 70 (hsp 70) for detection of gene expression changes, anti-fast myosin for the determination of muscle fibre types, and for detection of apoptotic gene expression...
Yamamoto M, Nakagawa K, Fujiwara K, Shimizu A, Ikeguchi M, Ikeguchi M.Equine β-lactoglobulin (ELG) assumes non-native helices during refolding and in partially folded states. Previously, circular dichroism (CD) combined with site-directed mutagenesis identified helical regions in the acid- and cold-denatured states of ELG. It is also known that a fragment of ELG, CHIBL (residues 88-142), has a structure similar to that of the cold-denatured state. For the study reported herein, the structure of a shorter fragment, CHIBLΔF (residues 97-142), was investigated by CD and nuclear magnetic resonance spectroscopy. The secondary chemical shifts clearly showed that non...
Graham-Thiers PM, Kronfeld DS, Kline KA.Dietary protein during conditioning and exercise must support additional needs while avoiding adverse metabolic effects. Ten Arabian horses were assigned randomly to 2 diets formulated to contain 7.5 or 14.5% crude protein and 12% fat. The low-protein diet (LP) was supplemented with lysine and threonine to match the levels of these amino acids in the high-protein diet (HP). Feed intake averaged 8.1 kg/day. Dietary cation-anion difference was 181.6 and 260.4 mmol/kg for high and low protein, respectively. Following 9 weeks conditioning, horses performed a repeated sprint test: 3 min walk at 1.5...
Ouellette AL, Evans RJ, Heath MF.Endotoxaemia is the leading cause of death in horses. Disseminated intravascular coagulation (DIG), stimulated by induced monocyte proteins, is a prominent feature. Monocyte-platelet cellular interactions are central to the vascular dysfunction produced by circulating endotoxin and are implicated in many thrombotic diseases in the horse. This study reports that endotoxin (0.01-10 microg ml(-1)) and blood platelets (2.5 x 10(7) - 1 x 10(8) ml(-1)) are potent inducers of expression and activity of monocyte tissue factor (TF), the primary activator of the blood coagulation protease cascade. The c...
Leadon DP, Jeffcott LB, Rossdale PD.Total calcium, total protein, albumin and globulin content were determined in 49 samples of mammary secretions from 37 crossbred and Thoroughbred mares. The mares were divided into three categories: Group 1--post partum samples from spontaneous full term Thoroughbred deliveries (n = 20); Group 2--pre- and post partum samples from spontaneous full term Thoroughbred deliveries (n = 6); Group 3--pre- and post partum samples from induced premature deliveries in crossbred mares (n = 11). Calcium concentrations of the mammary secretions proved useful in predicting full term and also in assessment of...
Gabay R, Rozen S, Samokovlisky A, Amor Y, Rosenfeld R, Kohen F, Amsterdam A, Berger P, Ben-Menahem D.CGβ subunits comprise a unique carboxyl-terminal peptide (CTP) that has multiple O-linked glycans and extends serum half-life of the protein. It has evolved by incorporating a previously untranslated region of the LHβ gene into the reading frame. Although CTP-like sequences are encrypted in the LHβ genes of several mammals, the CGβ subunit developed only in primates and equids. To study this restriction in evolution, we examined whether the cryptic CTP decoded from the bovine LHβ gene (boCTP) possesses key characteristics of the human (h) CGβ-CTP. The boCTP does not impede several crucia...
Liang FT, Granstrom DE, Timoney JF, Shi YF.We report a simple, economical, and efficient protocol for protein purification from cells. First, proteins of cell lysates were separated by standard sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and electroblotted to protein-blotting membrane. The blots were stained with Coomassie blue or developed by immunoblotting to visualize specific proteins. The bands corresponding to those visible by immunoblotting were excised from the dye-stained blots and subjected to isoelectric focusing. The focused gel was stained with Coomassie blue. Finally, the stained bands were excise...
Davis SL, Graf M, Morrison CA, Hall TR, Swift PJ.The chemical nature and variations in serum concentrations of growth hormone binding protein (GHBP) from humans, rabbits, and rodents have been reported. To date little is known about the GHBP of domestic animals. Therefore, we initiated these studies to determine whether a serum GHBP was present in domestic animals and to purify the binding protein (BP) from serum of selected species. Using a dextran-coated charcoal separation assay, specific growth hormone (GH) binding was demonstrated in ovine, bovine, chicken, human, goose, porcine, and equine serum (listed in sequence from lowest to highe...
Rutllant J, Meyers SA.It is generally accepted that spermatozoa become functionally mature during epididymal transit. The objective of this study was to determine whether the cellular location of equine PH-20 is modified during epididymal transit and, if so, the mechanism for such modification. Sperm were isolated from caput and cauda epididymal regions from stallions undergoing castration (n = 7) and used as whole sperm cell or subjected to nitrogen cavitation for isolation of plasma membrane proteins. Both caput and cauda sperm and sperm protein extracts were subjected to N-deglycosylation, O-deglycosylation, or ...
Iddagoda J, Gunasekara P, Handunnetti S, Jeewandara C, Karunatilake C, Malavige GN, de Silva R, Dasanayake D.It is clinically important to identify allergens in Artocarpus heterophyllus (jackfruit), Moringa oleifera (moringa), Trianthema portulacastrum (horse purslane) and Syzygium samarangense (rose apple). This study included 7 patients who developed anaphylaxis to jackfruit (1), moringa (2), horse purslane (3) and rose apple (1). We sought to determine allergens in the edible ripening stages of jackfruit (tender, mature, and ripened jackfruit) and seeds, edible parts of moringa (seeds, seedpod, flesh inside seedpod, and leaves), horse purslane leaves and ripened rose apple fruit. The persistence o...
