Peptides are short chains of amino acids that are involved in various biological processes in horses. They function as signaling molecules, influencing physiological activities such as metabolism, immune response, and tissue repair. Peptides can be naturally occurring or synthetically derived, and they may serve as therapeutic agents in veterinary medicine. In equine health, peptides are studied for their potential applications in enhancing performance, supporting recovery, and managing conditions like osteoarthritis. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and potential applications of peptides in the context of equine health and disease management.
Tong T, Bai Y, Liu G, Wang Q, Zhang W, Xiao Y, Xu S, Liu N, Yang T, Wu D.IL-18 is a cytokine originally discovered as an important modulator of immune responses and subsequently shown to be pleiotropic. In this report, we expressed the recombinant equine mature interleukin-18 (rEMIL-18) in E. coli and purified it by nickel affinity gel column chromatography. Purified rEMIL-18 had biological activity commensurate with recombinant human IL-18, as determined by its synergistic effect with recombinant human IL-12 (rhIL-12) on the induction of IFN-gamma gene expression in equine peripheral blood mononuclear cells (PBMC). Following intraperitoneal (i.p.) immunization of ...
Zhang J, Stein DA, Timoney PJ, Balasuriya UB.A significant consequence of equine arteritis virus (EAV) infection of horses is persistence of the virus in a variable percentage of infected stallions. We recently established an in vitro model of EAV persistence in cell culture for the purpose of furthering our understanding of EAV biology in general and viral persistence in the stallion in particular. In this study we investigated whether persistently infected HeLa cells could be cured of EAV infection by treatment with an antisense peptide-conjugated phosphorodiamidate morpholino oligomer (PPMO) designed to target the 5'-terminal region o...
Tóth F, Frank N, Martin-Jiménez T, Elliott SB, Geor RJ, Boston RC.Hyperinsulinaemia is detected in horses with insulin resistance (IR) and has previously been attributed to increased pancreatic insulin secretion. Connecting peptide (C-peptide) can be measured to assess pancreatic function because it is secreted in equimolar amounts with insulin and does not undergo hepatic clearance. Objective: A human double antibody radioimmunoassay (RIA) detects C-peptide in equine serum and concentrations would reflect responses to different stimuli and conditions. Methods: A validation procedure was performed to assess the RIA. Six mature mares were selected and somatos...
Bruhn O, Paul S, Tetens J, Thaller G.Defensins represent an important class of antimicrobial peptides. These effector molecules of the innate immune system act as endogenous antibiotics to protect the organism against infections with pathogenic microorganisms. Mammalian defensins are classified into three distinct sub-families (alpha-, beta- and theta-defensins) according to their specific intramolecular disulfide-bond pattern. The peptides exhibit an antimicrobial activity against a broad spectrum of microorganisms including bacteria and fungi. Alpha-Defensins are primarily synthesised in neutrophils and intestinal Paneth cells....
Pickles KJ, Brooks AC, Rickards KJ, Cunningham FM.N-terminal peptides derived from the anti-inflammatory peptide, annexin-1, inhibit neutrophil function but can also induce pro-inflammatory effects. Although equine annexin-1 has been sequenced, its cellular expression and properties have not been reported. This study has examined whether annexin-1 is present in equine leucocytes and how the N-terminal peptide, Ac2-26, affects equine neutrophil superoxide production. Annexin-1 expression in equine neutrophils and mononuclear cells and the ability of Ac2-26 to activate neutrophil p42/44 MAPK were determined by immunoblotting. Equine neutrophil ...
Timoney JF, DeNegri R, Sheoran A, Forster N.The clonal Streptococcus equi causes equine strangles, a highly contagious suppurative lymphadenopathy and rhinopharyngitis. An important virulence factor and vaccine component, the antiphagocytic fibrinogen binding SeM of S. equi is a surface anchored fibrillar protein. Two recent studies of N. American, Japanese and European isolates have revealed a high frequency of N-terminal amino acid variation in SeM of S. equi CF32 that suggests this region of the protein is subject to immunologic selection pressure. The aims of the present study were firstly to map regions of SeM reactive with convale...
Mitchell JD, Kuc RE, Maguire JJ, Davenport AP.The brain-gut peptide neuromedin U (NMU) is a ligand for the G-protein-coupled receptors, NMU1 and NMU2. In humans, an extended form of this peptide, NMU-25, and the structurally related peptide, neuromedin S (NMS), both produce potent vasoconstriction in isolated blood vessels. The aim of this study was to determine whether NMU fulfilled criteria for controlling vasoreactivity in the equine digital circulation. NMU receptors were characterised in the equine digital artery and vein based on the pharmacological criteria of specific, saturable and high affinity binding. Immunoreactive peptide wa...
Espino-Solis GP, Calderon-Amador J, Calderon-Aranda ES, Licea AF, Donis-Maturano L, Flores-Romo L, Possani LD.A three-dimensional model of the alphaX I-domain of the horse integrin CD11c from dendritic cells provided information for selecting two segments of the primary structure for peptide synthesis. Peptide 1 contains 20 amino acids and peptide 2 has 17 amino acid residues. The first spans from position Thr229 to Arg248 of an alpha-helix segment of the structure, whereas peptide 2 goes from Asp158 to Phe174 and corresponds to an exposed segment of the loop considered to be the metal ion-dependent adhesion site. Murine polyclonal antisera against both peptides were generated and assayed in periphera...
Heuzenroeder MW, Barton MD, Vanniasinkam T, Phumoonna T.The aim of this chapter is to provide a strategy for mapping linear antibody epitopes of protein antigens in order to discover candidates for vaccines or diagnostic tests. A set of overlapping peptides was designed and synthesised based upon a known amino acid sequence of the target protein, virulence-associated protein A (VapA) of the bacterium Rhodococcus equi, an important pulmonary pathogen in foals.The peptides were biotinylated and used in an ELISA to screen immune sera from foals. These biotinylated peptides were coated directly onto micro titre plates that had been pre-coated with Neut...
Chiocchetti R, Bombardi C, Mongardi-Fantaguzzi C, Venturelli E, Russo D, Spadari A, Montoneri C, Romagnoli N, Grandis A.This paper describes the morphology and distribution of the enteric nervous system (ENS) cells and fibres immunoreactive for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene-related peptide (CGRP), NF200kDa (NF200), and S100 protein. The percentages of subclasses of enteric neurons in the total neuronal population were investigated by the use of anti-PGP 9.5 or anti-NSE antibodies. ChAT-IR myenteric plexus (MP) and submucosal plexus (SMP) neurons were 66+/-7% and 74+/-15%, respectively, whereas those cells expressing nNOS-IR were 38+/-7...
Sasaki N, Tsuzuki N, Yamada M, Minami T, Yamada H.This study aimed to establish a standard dose and sample collection time for (13)C phenylalanine and (13)C-Dipeptide breath test in horses. To evaluate dose-dependent effects, healthy horses received 2.5 mg/kg, 5 mg/kg, and 10 mg/kg (13)C phenylalanine dissolved in 1 ml/kg distilled water and 1.25 mg/kg, 2.5 mg/kg, and 5 mg/kg (13)C dipeptide dissolved in 2 ml/ kg distilled water. Tmax was observed during the sample collection time. For (13)C phenylalanine, the standard deviation of Cmax at 5 mg/kg was lower than that of 10 mg/kg. For (13)C dipeptide, the standard deviation of Tmax was the low...
Venugopal CS, Holmes EP, Polikepahad S, Laborde S, Kearney M, Moore RM.The purpose of the study was to compare in vitro airway responses to neurokinin A & B (NKA and NKB) and expression of NK-2 receptors in airways of horses affected and unaffected with recurrent airway obstruction (RAO). Neurokinin-A, an inflammatory mediator belonging to the tachykinin family of neuropeptides, causes bronchoconstriction by binding to NK-2 receptors. Neurokinin-B is a lesser-known neuropeptide that acts on NK-3 receptors. Horses were placed into RAO-affected and RAO-unaffected groups based on their history, clinical scoring, and pulmonary function testing. Lung tissue from e...
de Grauw JC, van de Lest CH, van Weeren PR.Inflammation is an important feature of many joint diseases, and levels of cartilage biomarkers measured in synovial fluid may be influenced by local inflammatory status. Little is known about the magnitude and time course of inflammation-induced changes in cartilage tissue turnover as measured in vivo by synovial fluid markers. We aimed to study temporal changes in concentrations of inflammatory mediators, matrix metalloproteinase activity and cartilage biomarkers over 1 week in joints with experimentally induced inflammation. Methods: Localized inflammation was induced in the intercarpal joi...
Magee C, Foradori CD, Bruemmer JE, Arreguin-Arevalo JA, McCue PM, Handa RJ, Squires EL, Clay CM.The purpose of the present study was to evaluate the effects of kisspeptin (KiSS) on LH and FSH secretion in the seasonally estrous mare and to examine the distribution and connectivity of GnRH and KiSS neurons in the equine preoptic area (POA) and hypothalamus. The diestrous mare has a threshold serum gonadotropin response to iv rodent KiSS decapeptide (rKP-10) administration between 1.0 and 500 microg. Administration of 500 microg and 1.0 mg rKP-10 elicited peak, mean, and area under the curve LH and FSH responses indistinguishable to that of 25 microg GnRH iv, although a single iv injection...
Bruhn O, Cauchard J, Schlusselhuber M, Gelhaus C, Podschun R, Thaller G, Laugier C, Leippe M, Grötzinger J.Defensins are small effector molecules of the innate immune system, synthesised by various organisms including plants and animals. The peptides act as endogenous antibiotics with an antimicrobial activity against a broad spectrum of microbes including bacteria, fungi and viruses. alpha-Defensins are a subgroup of the defensin family, their synthesis is limited to some tissues and furthermore to some mammalian species including the horse. Equine DEFA1 is an enteric alpha-defensin exclusively produced in Paneth cells. The peptide showed an activity against a broad spectrum of microbes, but typic...
Ihm Y, Sparks WO, Lee JH, Cao H, Carpenter S, Wang CZ, Ho KM, Dobbs D.Rev is an essential regulatory protein in the equine infectious anemia virus (EIAV) and other lentiviruses, including HIV-1. It binds incompletely spliced viral mRNAs and shuttles them from the nucleus to the cytoplasm, a critical prerequisite for the production of viral structural proteins and genomic RNA. Despite its important role in production of infectious virus, the development of antiviral therapies directed against Rev has been hampered by the lack of an experimentally-determined structure of the full length protein. We have used a combined computational and biochemical approach to gen...
Ipiña Z, Lussier JG, Theoret CL.To clone full-length equine pigment epithelium-derived factor (PEDF) complementary DNA (cDNA) and to evaluate its temporal expression during repair of wounds in horses. Methods: 4 clinically normal 2-to 3-year-old Standardbred mares. Methods: Full-length equine PEDF cDNA was cloned by screening size-selected cDNA libraries derived from biopsy specimens obtained from the wound edge 7 days after experimental creation of a 6.25-cm(2) full-thickness wound in the skin of the lateral thoracic wall. Expression was evaluated in normal skin and in biopsy specimens obtained weekly from experimentally in...
Keenan DM, Alexander S, Irvine C, Veldhuis JD.Cortisol is an important mediator of physiological stress responses. Hypothalamic CRH and arginine vasopressin (AVP) and pituitary ACTH, in addition to hypothalamic and pituitary cortisol feedback, regulate cortisol secretion. Importantly, joint interactions among the four, rather than the signal of any one hormone, govern this life-preserving axis. Quantifying in vivo strength of such joint interactions has been difficult, especially without direct injection of cortisol, CRH, AVP, or ACTH. The goal of the present research was to estimate these joint feedback and feedforward interactions in vi...
Hobson-Peters J, Toye P, Sánchez MD, Bossart KN, Wang LF, Clark DC, Cheah WY, Hall RA.Using a monoclonal antibody directed to domain I of the West Nile virus (WNV) envelope (E) protein, we identified a continuous (linear) epitope that was immunogenic during WNV infection of horses. Using synthetic peptides, this epitope was mapped to a 19 aa sequence (WN19: E147-165) encompassing the WNV NY99 E protein glycosylation site at position 154. The inability of WNV-positive horse and mouse sera to bind the synthetic peptides indicated that glycosylation was required for recognition of peptide WN19 by WNV-specific antibodies in sera. N-linked glycosylation of WN19 was achieved through ...
Bailat AS, Soutullo AR, García MI, Veaute CM, Garcia L, Racca AL, Malan Borel IS.Gp90 and gp45 synthetic peptides, which mimic conserved sequences of native viral proteins, are recognized by antibodies to equine infectious anemia virus (EIAV) in asymptomatic carrier horses and generate humoral and cellular responses in immunized mice. Cytokine mRNA levels were evaluated in equine peripheral blood mononuclear cells (PBMCs) after in vitro stimulation with gp90 and gp45 with the aim of determining the cytokine profile associated with the proliferative response. Stimulation index (SI) values indicate that 100 and 60% of EIAV-infected horses recognized gp90 and gp45, respective...
Bailly-Chouriberry L, Pinel G, Garcia P, Popot MA, Le Bizec B, Bonnaire Y.Equine growth hormone (eGH) has been available since 1998 as an approved drug (EquiGen-5, Bresagen) containing recombinant eGH (reGH). It is suspected of being illegally administered to racehorses in order to improve physical performance and to speed-up wound healing. Thus it may be considered a doping agent which would require a sensitive and reliable method of identification and confirmation in order to regulate its use in racehorses. reGH differs from the native eGH by an additional methionine at the N-terminal (met-eGH) and has never been unambiguously detected in any type of biological ma...
Hobo S, Niwa H, Anzai T.The reactivity of the proline-glutamic acid-proline-lysine (PEPK) repetition peptide antigen in 3176 serum samples was investigated to evaluate its utility as an antigen for the serological diagnosis of strangles. The reactivity of the sera of horses infected with Streptococcus equi subspecies equi was high when the peptide had several PEPK repetitions. However, as the number of PEPK repetitions increased, the reactivity of the antigen with the sera of horses infected with Streptococcus equi subspecies zooepidemicus also increased. In horses infected experimentally with S equi, the reactivity ...
Guan F, Uboh CE, Soma LR, Birks E, Chen J, You Y, Rudy J, Li X.Recombinant human erythropoietin (rhEPO) and darbepoetin alfa (DPO) are protein-based drugs for the treatment of anemia in humans by stimulating erythrocyte production. However, these agents are abused in human and equine sports due to their potential to enhance performance. This paper describes the first method for differentiation and identification of rhEPO and DPO in equine plasma by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method comprised analyte extraction and enrichment by immunoaffinity separation with anti-rhEPO antibodies, dual digestion by trypsin an...
Iniesta J, Cooper HJ, Marshall AG, Heptinstall J, Walton DJ, Peterson IR.The iodination of proteins remains a useful tool in biochemistry for radiolabelling. However, chemical or enzymatic iodination is difficult to control and can give deleterious polyiodination. Previously, we have shown that electrooxidation with nitrite is a rapid method for the selective nitration of tyrosine residues in proteins. In principle, it should be possible to substitute a number of electrooxidisable anions into the tyrosine phenol ring. Electrochemical iodination is more difficult to control than nitration because the rapid anodic oxidation of I(-) leads to persistent formation of th...
Desantis S, Albrizio M, Ventriglia G, Deflorio M, Guaricci AC, Minoia R, De Metrio G.The presence of the mu-opioid receptor and the type of glycosylation in the third extra-cellular loop of this receptor was investigated in the isthmus of mare oviduct during oestrus by means of immunoblotting and immunohistochemistry combined with enzymatic (N-glycosidase F and O-glycosidase) and chemical (beta-elimination) treatments. Immunoblotting analysis showed that the mu-opioid receptor consists of two peptides with molecular weights of around 65 and 50 kDa. After N-deglycosylation with N-glycosidase F an additional immunoreactive peptide was observed at around 30 KDa. The cleavage of O...
Popot MA, Woolfitt AR, Garcia P, Tabet JC.The insulin-like-growth factor (IGF-I) peptide is considered to be the main indirect marker for growth hormone administration (GH) in a horse. Further to a previous investigation on measurement of IGF-I in plasma samples by mass spectrometry, this study focuses on quantitative and qualitative analysis of intact IGF-I in horse plasma. First, protein-transposing software has been developed for IGF-I to facilitate its quantification by HPLC-electrospray-ion-trap mass spectrometry. Second, product-ion scan experiments on IGF-I have been conducted on standard samples, non-fortified equine plasma sa...
Atasheva S, Garmashova N, Frolov I, Frolova E.Venezuelan equine encephalitis virus (VEEV) represents a continuous public health threat in the United States. It has the ability to cause fatal disease in humans and in horses and other domestic animals. We recently demonstrated that replicating VEEV interferes with cellular transcription and uses this phenomenon as a means of downregulating a cellular antiviral response. VEEV capsid protein was found to play a critical role in this process, and its approximately 35-amino-acid-long peptide, fused with green fluorescent protein, functioned as efficiently as did the entire capsid. We detected a...
Tagmyer TL, Craigo JK, Cook SJ, Even DL, Issel CJ, Montelaro RC.A highly effective attenuated equine infectious anemia virus (EIAV) vaccine (EIAV(D9)) capable of protecting 100% of horses from disease induced by a homologous Env challenge strain (EIAV(PV)) was recently tested in ponies to determine the level of protection against divergent Env challenge strains (J. K. Craigo, B. S. Zhang, S. Barnes, T. L. Tagmyer, S. J. Cook, C. J. Issel, and R. C. Montelaro, Proc. Natl. Acad. Sci. USA 104:15105-15110, 2007). An inverse correlation between challenge strain Env variation and vaccine protection from disease was observed. Given the striking differences in pro...
Kuuranne T, Thomas A, Leinonen A, Delahaut P, Bosseloir A, Schänzer W, Thevis M.Insulin is a peptide hormone consisting of two peptide chains (A- and B-chain) that are cross-linked by two disulfide bonds. To obtain improved pharmacokinetic onset of action profiles of insulin treatment in diabetic patients, recombinant long-, intermediate-, and rapid-acting insulin analogs are produced, in which the C-terminal end of the B-chain plays an especially important role.A review of the veterinary literature reveals the low prevalence of equine type I diabetes mellitus, which indicates that the therapeutic use of insulin in racing horses is unlikely. Although there is no unequivoc...
Hollis AR, Boston RC, Corley KT.Neonatal foals succumb rapidly to hypovolaemic shock in comparison to mature horses; they do not consistently increase their heart rate in response to hypotension and respond differently to fluid administration. The hormonal responses to hypovolaemia in the horse and foal require investigation. Objective: The hormonal responses to hypovolaemia and fluid administration differ between mature and neonatal horses. Methods: Five mature horses and 5 neonatal foals fulfilling predetermined criteria for hypovolaemia, were included in the study. A blood sample was taken at admission and after normalisa...
Hollis AR, Boston RC, Corley KT.Neonatal foals succumb rapidly to hypovolaemic shock in comparison to mature horses; they do not consistently increase their heart rate in response to hypotension and respond differently to fluid administration. The hormonal responses to hypovolaemia in the horse and foal require investigation. Objective: The hormonal responses to hypovolaemia and fluid administration differ between mature and neonatal horses. Methods: Five mature horses and 5 neonatal foals fulfilling predetermined criteria for hypovolaemia, were included in the study. A blood sample was taken at admission and after normalisa...
Schlusselhuber M, Jung S, Bruhn O, Goux D, Leippe M, Leclercq R, Laugier C, Grötzinger J, Cauchard J.Rhodococcus equi, the causal agent of rhodococcosis, is a severe pathogen of foals but also of immunodeficient humans, causing bronchopneumonia. The pathogen is often found together with Klebsiella pneumoniae or Streptococcus zooepidemicus in foals. Of great concern is the fact that some R. equi strains are already resistant to commonly used antibiotics. In the present study, we evaluated the in vitro potential of two equine antimicrobial peptides (AMPs), eCATH1 and DEFA1, as new drugs against R. equi and its associated pathogens. The peptides led to growth inhibition and death of R. equi and ...
Bannai H, Nemoto M, Tsujimura K, Ohta M.An enzyme-linked immunosorbent assay (ELISA) using a synthetic peptide for the E2 glycoprotein was developed for the serodiagnosis of Getah virus infection in horses. To identify an immunogenic epitope, a series of 20-mer peptides (n = 22) for the E2 protein was screened with pooled sera from horses infected with Getah virus. Peptide P11 (PTEEEIDMHTPPDIPDITLL) showed the strongest reaction. ELISA using P11 (E2-P11-ELISA) detected increased antibody levels in all seven experimentally infected horses and in five out of nine vaccinated horses. Out of 28 naturally infected horses, 25 were sero...
Richards SL, Cawley AT, Cavicchioli R, Suann CJ, Pickford R, Raftery MJ.Over recent years threats to racing have expanded to include naturally occurring biological molecules, such as peptides and proteins, and their synthetic analogues. Traditionally, antibodies have been used to enable detection of these compounds as they allow purification and concentration of the analyte of interest. The rapid expansion of peptide-based therapeutics necessitates a similarly rapid development of suitable antibodies or other means of enrichment. Potential alternative enrichment strategies include the use of aptamers, which offer the significant advantage of chemical synthesis onc...
Billinghurst RC, Buxton EM, Edwards MG, McGraw MS, McIlwraith CW.To develop an antibody that specifically recognizes collagenase-cleaved type-II collagen in equine articular cartilage. Methods: Cartilage specimens from horses euthanatized for problems unrelated to the musculoskeletal system. Methods: A peptide was synthesized representing the carboxy- (C-) terminus (neoepitope) of the equine type-II collagen fragment created by mammalian collagenases. This peptide was used to produce a polyclonal antibody, characterized by western analysis for reactivity to native and collagenase-cleaved equine collagens. The antibody was evaluated as an antineoepitope anti...
Schlusselhuber M, Guldbech K, Sevin C, Leippe M, Petry S, Grötzinger J, Giguère S, Cauchard J.The equine antimicrobial peptide eCATH1 previously has been shown to have in vitro activity against antibiotic-susceptible reference strains of Rhodococcus equi and common respiratory bacterial pathogens of foals. Interestingly, eCATH1 was also found to be effective in the treatment of R. equi infection induced in mice. The aim of this study was to assess the in vitro activity of eCATH1 against equine isolates of Gram-negative (Escherichia coli, Salmonella enterica, Klebsiella pneumoniae and Pseudomonas spp.) and Gram-positive (R. equi, Staphylococcus aureus) bacteria resistant to multiple cla...
Albrizio M, Lacalandra GM, Micera E, Guaricci AC, Nicassio M, Zarrilli A.Opioid receptors and endogenous opioid peptides act not only in the control of nociceptive pathways, indeed several reports demonstrate the effects of opiates on sperm cell motility and morphology suggesting the importance of these receptors in the modulation of reproduction in mammals. In this study we investigated the expression of delta opioid receptors on equine spermatozoa by western blot/indirect immunofluorescence and its relationship with sperm cell physiology. Methods: We analyzed viability, motility, capacitation, acrosome reaction and mitochondrial activity in the presence of naltri...
Linke RP, Geisel O, Mann K.Amyloid deposits from equine cutaneous nodular amyloidosis associated with extramedullary plasmacytoma were classified immunohistochemically as equine immunoglobulin lambda-light chain-derived and designated eA lambda (HIP). For chemical identification, the amyloid fibril proteins were separated on Sephadex G-100 in 6M guanidine.HCl. Polypeptides of predominantly 24 kDa and 50 kDa were found by polyacrylamide gel electrophoresis. They have preponderance of immunoglobulin lambda-antigenic determinants as detected by immunodiffusion and immunoblotting. Since the N-terminus of the major proteins ...
Russi RC, Garcia L, Cámara MS, Soutullo AR.Equine infectious anaemia (EIA) is controlled by the identification of seropositive animals. The official diagnostic method is the agar gel immunodiffusion (AGID) test, which detects antibodies against a viral core protein (p26). Although AGID is inexpensive and specific, the report of results takes considerable time and the test has low analytical sensitivity. Objective: To validate our in-house indirect ELISA , following the World Organization of Animal Health (OIE) criteria. Methods: Test validation. Methods: Synthetic peptides gp90 and gp45 were used as antigens in ELISA . Tests used for v...
Araújo-Viel MS, Juliano MA, Oliveira L, Prado ES.The effect of secondary-subsite interactions on the catalytic efficiency of horse urinary kallikrein was studied using as substrates oligopeptides and peptidyl-4-nitroanilides with L-Arg at P1. The known secondary specificity of tissue kallikreins for hydrophobic residues at P2 was also demonstrated for horse urinary kallikrein and a higher preference of this enzyme for L-Phe over L-Leu at P2 was evident. Interaction of subsites S3 with D-Pro and D-Phe enhanced the catalytic efficiency but tripeptidyl-4-nitroanilides with acetyl-D-Pro, L-Pro and acetyl-L-Pro at P3 were no better substrates tha...
Moore RM, Sedrish SA, Holmes EP, Koch CE, Venugopal CS.The objective of this study was to determine and compare the in vitro responses of equine large colon arterial and venous rings to vasodilatory neuropeptides; calcitonin gene-related peptide (CGRP); substance P (SP); vasoactive intestinal polypeptide (VIP); and acetylcholine (ACh), a standard nonpeptide endothelium-dependent vasodilator. Responses of vessel rings to graded concentrations (10(-11) M to 10(-5) M) of each drug were determined in endothelium-intact, denuded, and Nomega-nitro-L-arginine methyl ester (L-NAME, 10(-5) M)-treated rings that were pre-contracted with norepinephrine. Perc...
Ho EN, Kwok WH, Lau MY, Wong AS, Wan TS, Lam KK, Schiff PJ, Stewart BD.A veterinary preparation known as TB-500 and containing a synthetic version of the naturally occurring peptide LKKTETQ has emerged. The peptide segment (17)LKKTETQ(23) is the active site within the protein thymosin β(4) responsible for actin binding, cell migration and wound healing. The key ingredient of TB-500 is the peptide LKKTETQ with artificial acetylation of the N-terminus. TB-500 is claimed to promote endothelial cell differentiation, angiogenesis in dermal tissues, keratinocyte migration, collagen deposition and decrease inflammation. In order to control the misuse of TB-500 in equin...
Brazil TJ, Rossi AG, Haslett C, McGorum B, Dixon PM, Chilvers ER.The synthetic formylpeptide fMLP is widely used as a model chemoattractant and secretagogue for mammalian neutrophils. Despite possessing fMLP receptors, equine neutrophils do not produce superoxide anions in response to fMLP and there is no inflammatory reaction in the horse when fMLP is injected intradermally. The functional capability of these receptors was investigated after pretreatment with recognized priming agents. Purified neutrophils were pretreated with lipopolysaccharide (LPS), platelet-activating factor (PAF), or tumor necrosis factor alpha (TNF-alpha) and superoxide anion generat...
Tencza SB, Islam KR, Kalia V, Nasir MS, Jolley ME, Montelaro RC.The control of equine infectious anemia virus (EIAV) infections of horses has been over the past 20 years based primarily on the identification and elimination of seropositive horses, predominantly by a standardized agar gel immunodiffusion (AGID) assay in centralized reference laboratories. This screening for EIAV-seropositive horses has been to date hindered by the lack of a rapid diagnostic format that can be easily employed in the field. We describe here the development of a rapid solution-phase assay for the presence of serum antibodies to EIAV based on fluorescence polarization (FP) (pat...
Science (New York, N.Y.)June 10, 1994
Volume 264, Issue 5165 1584-1587 doi: 10.1126/science.7515512
Willbold D, Rosin-Arbesfeld R, Sticht H, Frank R, Rösch P.Trans-activator (Tat) proteins regulate the transcription of lentiviral DNA in the host cell genome. These RNA binding proteins participate in the life cycle of all known lentiviruses, such as the human immunodeficiency viruses (HIV) or the equine infectious anemia virus (EIAV). The consensus RNA binding motifs [the trans-activation responsive element (TAR)] of HIV-1 as well as EIAV Tat proteins are well characterized. The structure of the 75-amino acid EIAV Tat protein in solution was determined by two- and three-dimensional nuclear magnetic resonance methods and molecular dynamics calculatio...
Timms M, Hall N, Levina V, Vine J, Steel R.The growth hormone releasing peptides (GHRPs) hexarelin, ipamorelin, alexamorelin, GHRP-1, GHRP-2, GHRP-4, GHRP-5, and GHRP-6 are all synthetic met-enkephalin analogues that include unnatural D-amino acids. They were designed specifically for their ability to stimulate growth hormone release and may serve as performance enhancing drugs. To regulate the use of these peptides within the horse racing industry and by human athletes, a method is presented for the extraction, derivatization, and detection of GHRPs from equine and human urine. This method takes advantage of a highly specific solid-ph...
Zhang J, Wu M, Ma Z, Zhang Y, Cao H.Donkey-hide gelatin is an important traditional Chinese medicine made from donkey skin. Despite decades of effort, identifying the animal materials (donkeys, horses, cattle and pigs) in donkey-hide gelatin remains challenging. In our study, we aimed to identify marker peptides of donkey-hide gelatin and its adulterants and develop a liquid chromatography-tandem mass spectrometry method to identify them. Theoretical marker peptides of four animals (donkeys, horses, cattle and pigs) were predicted and verified by proteomic experiments, and 12 species-specific marker peptides from donkey-hide gel...
Huang L, Palmieri C, Bertin FR.Pituitary pars intermedia dysfunction (PPID) is an endocrinopathy commonly affecting old horses. It is a spontaneously occurring, progressive disease that is still poorly understood. Previous studies have observed neurodegeneration of the dopaminergic inhibition of melanotrophs, which leads to decreased dopamine (DA) in the pars intermedia (PI) and increased pro-opiomelanocortin-derived peptides circulating in plasma. However, rats knockout for the dopamine D2 receptor (D2r) similarly develop PI hypertrophy and hyperplasia. Thus, based on the current pathophysiological theory of PPID, whether ...
Rhalem A, Sahibi H, Lasri S, Johnson WC, Kappmeyer LS, Hamidouch A, Knowles DP, Goff WL.A highly specific and sensitive competitive enzyme-linked immunosorbent assay for detection of specific antibody to Babesia equi in serum from equids was validated for use in Morocco. The assay is based on the specific inhibition of binding of a monoclonal antibody to a conserved epitope within a recombinant parasite peptide by serum from infected animals. The assay was compared to an established indirect immunofluorescence assay, with a concordance of 91%. The assay was used to determine seroprevalence for B. equi infections in donkeys and horses throughout Morocco. A total of 578 sera (163 h...
Li N, Dou S, Feng L, Zhu Q, Lu N.In matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), the analyte is usually distributed unevenly throughout the sample spot. The area with aggregated analyte molecules contributing abundant signal, is termed as "sweet spot", which results in poor detection reproducibility and makes it impossible to quantify analytes without internal standards. We proposed a strategy to eliminate sweet spot in MALDI-MS by using a hydrophobic ordered structure as target. The target is fabricated by creating a hydrophobic silicon nanopillar array and subsequently decorating it uniformly wi...
Scopel e Silva D, de Castro CC, da Silva e Silva F, Sant'anna V, Vargas GD, de Lima M, Fischer G, Brandelli A, da Motta Ade S, Hübner Sde O.P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity a...
Ryan MP, McAuliffe O, Ross RP, Hill C.Lacticin 3147 is a broad-spectrum, two-component, lanthionine-containing bacteriocin produced by Lactococcus lactis DPC3147 which has widespread food and biomedical applications as a natural antimicrobial. Other two-component lantibiotics described to date include cytolysin and staphylococcin C55. Interestingly, cytolysin, produced by Enterococcus faecalis, has an associated haemolytic activity. The objective of this study was to compare the biological activity of lacticin 3147 with cytolysin. The lacticin 3147-encoding determinants were heterologously expressed in Ent. faecalis FA2-2, a plasm...
Schaufuss P, Müller F, Valentin-Weigand P.Haemolytic activities of Trichophyton (T.) mentagrophytes were detected and characterized by qualitative and quantitative assays. On Columbia agar supplemented with blood from horses, cattle or sheep, T. mentagrophytes expressed a strong zone of complete haemolysis. No haemolytic activities could be detected in the closely related T. verrucosum var. ochraceum. The same results were obtained after cultivation of the fungi on sterile cellulose acetate filters placed on the surface on Columbia blood agar. After removal of the filter, complete haemolysis was detected below the colony of T. mentagr...
Xiao T, Zeng J, Zhao C, Hou Y, Wu T, Deng Z, Zheng L.An infant in vitro digestion model was utilized to investigate protein digestion characteristics in human and diverse mammalian milk (i.e., cow, goat, sheep, mare, and camel milk) using electrophoresis and chromatography. Digestive differences among milks were mainly manifested in the infant gastric phase, as evidenced by varying degrees of protein digestion. Notably, proteins (i.e., lactoferrin, serum albumin, and immunoglobulin G-heavy chain) remained partially intact in human milk, whereas these proteins in animal milk were exclusively degraded after gastrointestinal digestion. The peptide ...
Bonicel J, Couchoud P, Foglizzo E, Desnuelle P, Chapus C.The complete sequence of the 96 residues composing horse colipase B has been determined by automated analysis of the intact protein, of two CNBr peptides and two tryptic peptides arising, respectively, from the citraconylated chain and from the unreduced protein. The single histidine of the protein is located at position 29 as in horse colipase A. His86, present in the C-terminal region of the pig cofactor and supposed to play a role in the folding molecule, is not conserved in horse B. Large pieces of the pig and horse B chains were found to be identical or very similar, especially the N-term...
Tsogtgerel M, Komyo N, Murase H, Hannan MA, Watanabe K, Ohtaki T, Tsumagari S, Kawate N, Nambo Y.Insulin-like peptide 3 (INSL3) is an important hormone for testicular descent during embryonic development and a factor for assessing functional status of Leydig cells of testes, but there is limited number of equine studies. Anti-Müllerian hormone (AMH) is a useful diagnostic marker for cryptorchidism in horses. This study aimed to compare serum concentrations and testicular expression intensity of INSL3 and AMH in intact and cryptorchid male horses. Serum INSL3 concentrations in intact (n = 9; mean ± SEM, 19.9 ± 5.9 ng/mL) and noncastrated unilateral cryptorchid (UC) male horses (n...
Yasui T, Fukui K, Nara T, Habata I, Meyer W, Tsukise A.The present study revealed in detail the subcellular localization of lysozyme and beta-defensin in the apocrine glands of the equine scrotal skin, a specific body region. The apocrine glandular cells were equipped with a varying number of secretory granules, a well-developed Golgi apparatus and abundant cisternae of the rough endoplasmic reticulum within their cytoplasm. In these cells, reactive gold particles representing lysozyme were detectable in the secretory granules as well as the Golgi apparatus and elements of the rough endoplasmic reticulum. Additionally, the antimicrobial peptide gr...
Schneider DA, Sayegh AI.There exists individual enteroendocrine cells spread throughout the gastrointestinal mucosa that release specific peptide, as well as nonpeptide, hormones to have various endocrine action on target cells bearing cell surface receptors selectively sensitive to these regulatory substances. Following receptor activation, a series of events is set into motion that serves to transduce the information imparted to the target cell. Such transduction mechanisms are numerous, and may be excitatory or inhibitory to the cell depending upon which G-protein subunits the receptor is coupled.
