Topic:Metabolites
Metabolites are small molecules involved in the metabolic processes within a horse's body. They are the intermediates and products of metabolism, encompassing a wide range of compounds, such as amino acids, lipids, carbohydrates, and nucleotides. These molecules play roles in energy production, growth, and cellular repair. The study of equine metabolites, often conducted through metabolomics, provides insights into the physiological and pathological states of horses. Changes in metabolite levels can indicate alterations in metabolic pathways, potentially reflecting health conditions or responses to environmental factors. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, function, and diagnostic potential of metabolites in equine health.
The effect of alphacypermethrin-treated mesh protection against African horse sickness virus vectors on jet stall microclimate, clinical variables and faecal glucocorticoid metabolites of horses. African horse sickness (AHS) is of importance to health and international trade in horses worldwide. During export from and transit through AHS endemic countries or zones, physical and chemical measures to protect horses from the vectors of AHS virus (AHSV) are recommended by the World Organization for Animal Health. Protection of containerized air transport systems for horses (jet stalls) with alphacypermethrin insecticide-treated high density polyethylene mesh is effective in reducing the Culicoides midge vector attack rate. In order to determine the effect of this mesh on jet stall ventilat...
Comprehensive solid-phase extraction of multitudinous bioactive peptides from equine plasma and urine for doping detection. The ability to analyze biological samples for multitudinous exogenous peptides with a single analytical method is desired for doping control in horse racing. The key to achieving this goal is the capability of extracting all target peptides from the sample matrix. In the present study, theory of mixed-mode solid-phase extraction (SPE) of peptides from plasma is described, and a generic mixed-mode SPE procedure has been developed for recovering multitudinous exogenous peptides with remarkable sequence diversity, from equine plasma and urine in a single procedure. Both the theory and the develop...
Online turbulent flow extraction coupled with liquid chromatography-tandem mass spectrometry for high throughput screening of anabolic steroids in horse urine. A high throughput method for simultaneous screening of anabolic steroids and their metabolites (4-esterendione, trenbolone, boldenone, oxandrolone, nandrolone, methandrostenolone, testosterone, 1-androstendione, ethisterone, normethandrolone, methyltestosterone, 16β-Hydroxystanozolol, epitestosterone, bolasterone, norethandrolone, danazol, stanozolol and androstadienone) in equine urine by online turbulent flow extraction coupled with liquid chromatography-tandem mass spectrometry was developed. The use of turbulent flow chromatography could simplify pretreatment of horse urine, which has com...
Evidence of boldenone, nandrolone, 5(10)-estrene-3β-17α-diol and 4-estrene-3,17-dione as minor metabolites of testosterone in equine. The detection of boldenone, nandrolone, 5(10)-estrene-3β,17α-diol, and 4-estrene-3,17-dione in a urine sample collected from a gelding having been treated with testosterone (500 mg 'Testosterone Suspension 100', single dose, injected intramuscularly) in 2009 led the authors' laboratory to suspect that these 'testicular' steroids could be minor metabolites of testosterone in geldings. Administration trials on six castrated horses with Testosterone Suspension 100 confirmed that low levels of boldenone, nandrolone, 5(10)-estrene-3β,17α-diol, and 4-estrene-3,17-dione could indeed be detected ...
Livestock metabolomics and the livestock metabolome: A systematic review. Metabolomics uses advanced analytical chemistry techniques to comprehensively measure large numbers of small molecule metabolites in cells, tissues and biofluids. The ability to rapidly detect and quantify hundreds or even thousands of metabolites within a single sample is helping scientists paint a far more complete picture of system-wide metabolism and biology. Metabolomics is also allowing researchers to focus on measuring the end-products of complex, hard-to-decipher genetic, epigenetic and environmental interactions. As a result, metabolomics has become an increasingly popular "omics" app...
From chromatogram to analyte to metabolite. How to pick horses for courses from the massive web resources for mass spectral plant metabolomics. The grand challenge currently facing metabolomics is the expansion of the coverage of the metabolome from a minor percentage of the metabolic complement of the cell toward the level of coverage afforded by other post-genomic technologies such as transcriptomics and proteomics. In plants, this problem is exacerbated by the sheer diversity of chemicals that constitute the metabolome, with the number of metabolites in the plant kingdom generally considered to be in excess of 200 000. In this review, we focus on web resources that can be exploited in order to improve analyte and ultimately metabol...
Challenges in detecting substances for equine anti-doping. The artificial increase of the physical capability of horses using drugs is well known in racing and other equine sports. Both illicit and therapeutic substances are regarded as prohibited substances in competition in most countries. Some countries make distinctions for a few, specific drugs which are, however, allowed for use in other countries. The primary objective in the case of doping control is the detection of any trace of drug exposure, either parent drug or any of its metabolites, using the most powerful analytical methods which are generally based on chromatographic/mass spectrometri...
Effect of the α2 -receptor agonists medetomidine, detomidine, xylazine, and romifidine on the ketamine metabolism in equines assessed with enantioselective capillary electrophoresis. The combination of ketamine and an α -receptor agonist is often used in veterinary medicine. Four different α -receptor agonists, medetomidine, detomidine, xylazine, and romifidine, which differ in their chemical structure and thus in selectivity for the α -receptor and in the sedative and analgesic potency, are typically employed during surgery of equines. Recovery following anesthesia with ketamine and an α -receptor agonist is dependent on the α -receptor agonist. This prompted us to investigate (i) the inhibition characteristics for the N-demethylation of ketamine to norketamine and (...
Revealing the influence of glucocorticoid treatment on the excretion of anabolic-androgenic steroids in horses through in vitro digestive simulations and an in vivo case study. Anabolic-androgenic steroids (AAS) are strictly forbidden in equine sports because of their stimulating effect on muscle growth and performance. Nevertheless, low levels of AAS have been found in some horses, untreated with AAS. Glucocorticoids (GC), used as an anti-inflammatory therapy and structurally related to AAS, might play a role in this phenomenon. In order to unravel this possible correlation the influence of glucocorticoid treatment on the excretion of AAS was studied both in vivo and in vitro. In vivo effects were investigated by analysing urine samples collected from a gelding trea...
Understanding the response to endurance exercise using a systems biology approach: combining blood metabolomics, transcriptomics and miRNomics in horses. Endurance exercise in horses requires adaptive processes involving physiological, biochemical, and cognitive-behavioral responses in an attempt to regain homeostasis. We hypothesized that the identification of the relationships between blood metabolome, transcriptome, and miRNome during endurance exercise in horses could provide significant insights into the molecular response to endurance exercise. For this reason, the serum metabolome and whole-blood transcriptome and miRNome data were obtained from ten horses before and after a 160 km endurance competition. We obtained a global regulatory ...
Comparison of jugular and transverse facial venous sinus blood analytes in healthy and critically ill adult horses. To compare blood gas, electrolyte, and metabolic analysis results between blood obtained by jugular and transverse facial venous sinus (TFVS) venipuncture in healthy adult horses and sick adult horses presented for emergency evaluation. Methods: Prospective, experimental study, from June 2012 to October 2013. Methods: Large animal university teaching hospital. Methods: Ten healthy adult University-owned horses and 48 client-owned adult horses (≥2 years old) presenting to the large animal hospital emergency service for medical or surgical evaluation of systemic illness. Methods: Venipunctures...
In vitro phase I metabolism of selective estrogen receptor modulators in horse using ultra-high performance liquid chromatography-high resolution mass spectrometry. Selective estrogen receptor modulators (SERMs) are chemicals that possess the anti-oestrogenic activities that are banned 'in' and 'out' of competition by the World Anti-Doping Agency (WADA) in human sports, and by the International Federation of Horseracing Authorities (IFHA) in horseracing. SERMs can be used as performance-enhancing drugs to boost the level of androgens or to compensate for the adverse effects as a result of extensive use of androgenic anabolic steroids (AASs). SERMs have indeed been abused in human sports; hence, a similar threat can be envisaged in horseracing. Numerous an...
Influence of respiratory tract disease and mode of inhalation on detectability of budesonide in equine urine and plasma. OBJECTIVE To evaluate the influence of respiratory tract disease (ie, recurrent airway obstruction [RAO]) and mode of inhalation on detectability of inhaled budesonide in equine plasma and urine samples. ANIMALS 16 horses (8 healthy control horses and 8 horses affected by RAO, as determined by results of clinical examination, blood gas analysis, bronchoscopy, and cytologic examination of bronchoalveolar lavage fluid). PROCEDURES 4 horses of each group inhaled budesonide (3 μg/kg) twice daily for 10 days while at rest, and the remaining 4 horses of each group inhaled budesonide during lunging ...
The Analysis of Phenylbutazone and Its Active Metabolite, Oxyphenbutazone, in Equine Tissues (Muscle, Kidney, and Liver), Urine, and Serum by LC-MS/MS. This study reports the use of two validated LC with tandem MS (MS/MS) methods to study the residue depletion profile of phenylbutazone (PBZ) and its metabolite oxyphenbutazone (OXPBZ) from equine serum, urine, and muscle, kidney, and liver tissues. One LC-MS/MS method, with an LOQ of 1.0 ng/mL for PBZ and 2.0 ng/mL for OXPBZ, was used for the analysis of the two drugs in the biological fluids (equine urine and serum); the other LC-MS/MS method, with an LOQ of 0.5 ng/g for PBZ and OXPBZ, was used for the analysis of the drugs in the equine tissue samples. PBZ was administered intravenously to t...
A comparison of fecal steroid metabolite concentrations between harem and bachelor stallions in a free-Ranging population of przewalski’s horses (Equus ferus przewalskii). The aim of this study was to determine whether concentrations of reproductive steroid hormone metabolites significantly differed between harem stallions and bachelor stallions in the free ranging group of Przewalski's horses (Equus ferus przewalskii) at the Hortobágy National Park in Hungary. Throughout the study, fecal samples were collected from 21 harem stallions and 15 bachelor stallions and analyzed for immunoreactive estrogen and androgen metabolites. Harem stallions demonstrated significantly higher concentrations of estrogen (P < 0.001) and epi-androsterone (P < 0.001), ...
Pharmacokinetics and in vitro efficacy of salicylic acid after oral administration of acetylsalicylic acid in horses. Although acetylsalicylic acid (ASA) is not frequently used as a therapeutic agent in horses, its metabolite SA is of special interest in equestrianism since it is a natural component of many plants used as horse feed. This led to the establishment of thresholds by horse sport organizations for SA in urine and plasma. The aim of this study was to investigate plasma and urine concentrations of salicylic acid (SA) after oral administration of three different single dosages (12.5 mg/kg, 25 mg/kg and 50 mg/kg) of acetylsalicylic acid (ASA) to eight horses in a cross-over designed study. Results:...
A review of designer anabolic steroids in equine sports. In recent years, the potential for anabolic steroid abuse in equine sports has increased due to the growing availability of designer steroids. These compounds are readily accessible online in 'dietary' or 'nutritional' supplements and contain steroidal compounds which have never been tested or approved as veterinary agents. They typically have unusual structures or substitution and as a result may pass undetected through current anti-doping screening protocols, making them a significant concern for the integrity of the industry. Despite considerable focus in human sports, until recently there ...
The relationship of muscle perfusion and metabolism with cardiovascular variables before and after detomidine injection during propofol-ketamine anaesthesia in horses. To study in horses (1) the relationship between cardiovascular variables and muscle perfusion during propofol-ketamine anaesthesia, (2) the physiological effects of a single intravenous (IV) detomidine injection, (3) the metabolic response of muscle to anaesthesia, and (4) the effects of propofol-ketamine infusion on respiratory function. Methods: Prospective experimental study. Methods: Seven standardbred trotters, 5-12 years old, 416-581 kg. Methods: Anaesthesia was induced with intravenous (IV) guaifenesin and propofol (2 mg kg) and maintained with a continuous IV infusion of propofol (0.15...
Pharmacokinetics of dextromethorphan and its metabolites in horses following a single oral administration. Dextromethorphan is an N-methyl-D-aspartate (NMDA) non-competitive antagonist commonly used in human medicine as an antitussive. Dextromethorphan is metabolized in humans by cytochrome P450 2D6 into dextrorphan, which is reported to be more potent than the parent compound. The goal of this study is to describe the metabolism of and determine the pharmacokinetics of dextromethorphan and its major metabolites following oral administration to horses. A total of 23 horses received a single oral dose of 2 mg/kg. Blood samples were collected at time 0 and at various times up to 96 h post drug ad...
Equine hepatocytes: isolation, cryopreservation, and applications to in vitro drug metabolism studies. Despite reports of the successful isolation of primary equine hepatocytes, there are no published data regarding the successful cryopreservation of these isolated cells. In this study, a detailed description of the procedures for isolation, cryopreservation, and recovery of equine hepatocytes are presented. Furthermore, the intrinsic clearance (Cl) and production of metabolites for three drugs were compared between freshly isolated and recovered cryopreserved hepatocytes. Primary equine hepatocytes were isolated using a two-step collagenase perfusion method, with an average cell yield of 2.47...
Pharmacokinetic profiles of the active metamizole metabolites in healthy horses. Metamizole (MT) is an analgesic and antipyretic drug labelled for use in humans, horses, cattle, swine and dogs. MT is rapidly hydrolysed to the active primary metabolite 4-methylaminoantipyrine (MAA). MAA is formed in much larger amounts compared with other minor metabolites. Among the other secondary metabolites, 4-aminoantipyrine (AA) is also relatively active. The aim of this research was to evaluate the pharmacokinetic profiles of MAA and AA after dose of 25 mg/kg MT by intravenous (i.v.) and intramuscular (i.m.) routes in healthy horses. Six horses were randomly allocated to two equally...
Equine atypical myopathy: A metabolic study. Atypical myopathy (AM) is a potentially fatal disease of grazing horses. It is reportedly caused by the ingestion of sycamore seeds containing toxic hypoglycin A. In order to study metabolic changes, serum and urine samples from nine horses with atypical myopathy and 12 control samples from clinically healthy horses were collected and then analysed using a high-performance liquid chromatography coupled with tandem mass spectrometry; serum metabolic profiles as the disease progressed were also studied. Metabolic data were evaluated using unsupervised and supervised multivariate analyses. Signif...
Analysis of phenylbutazone residues in horse tissues with and without enzyme-hydrolysis by LC-MS/MS. Phenylbutazone (PBZ) is permitted to be used for the treatment of musculoskeletal pain and inflammation in race horses but it is not approved for use in horses destined for human consumption. In a recent study initiated in our laboratory to study the disposition of PBZ and its oxyphenbutazone (OXPBZ) metabolite in equine tissues, we compared the effect of an additional enzymatic hydrolysis step with ß-glucuronidase on the results of the analysis for PBZ without enzymatic hydrolysis. Incurred tissue samples obtained from a female horse dosed with PBZ at 8.8 mg/kg for 3 days and sacrificed ...
In vitro analysis of the effect of supplementation with activated charcoal on the equine hindgut. The present study uses in vitro analytical techniques to investigate the effect of activated charcoal on the microbial community of the equine hindgut and the metabolites they produce. Incubations were performed in Wheaton bottles using a 50 ml incubation of a high-energy feed or a low-energy feed, plus bottles with no added food source, together with five levels of activated charcoal (0, 10, 25, 50 or 100 mg per bottle) and fecal samples as a bacterial inoculum. Using this method the rate of gas production, volatile fatty acid and ammonia concentrations, and pH values were analyzed and found ...
Effects of deoxynivalenol (DON), zearalenone (ZEN), and related metabolites on equine peripheral blood mononuclear cells (PBMC) in vitro and background occurrence of these toxins in horses. Both deoxynivalenol (DON), zearalenone (ZEN), and their metabolites are known to modulate immune cells in various species whereby viability and proliferation are influenced. Such effects were rarely examined in horses. Therefore, one aim of the present study was to titrate the inhibitory concentrations of DON, 3-acetyl-DON (3AcDON), de-epoxy-DON (DOM-1), ZEN, and α- and β-zearalenol (ZEL) at which viability and proliferation of equine PBMC were reduced by 50 % (IC50) and 10 % (IC10) in vitro. For evaluation of practical relevance of the in vitro findings, a further aim was to screen horses...
Fecal Glucocorticoid Analysis: Non-invasive Adrenal Monitoring in Equids. Adrenal activity can be assessed in the equine species by analysis of feces for corticosterone metabolites. During a potentially aversive situation, corticotrophin releasing hormone (CRH) is released from the hypothalamus in the brain. This stimulates the release of adrenocorticotrophic hormone (ACTH) from the pituitary gland, which in turn stimulates release of glucocorticoids from the adrenal gland. In horses the glucocorticoid corticosterone is responsible for several adaptations needed to support equine flight behaviour and subsequent removal from the aversive situation. Corticosterone met...
Investigation of the selective androgen receptor modulators S1, S4 and S22 and their metabolites in equine plasma using high-resolution mass spectrometry. Selective androgen receptor modulators (SARMs) are prohibited in sports due to their performance enhancing ability. It is important to investigate the metabolism to determine appropriate targets for doping control. This is the first study where the equine metabolites of SARMs S1, S4 (Andarine) and S22 (Ostarine) have been studied in plasma. Methods: Each SARM was administered to three horses as an intravenous bolus dose and plasma samples were collected. The samples were pretreated with protein precipitation using cold acetonitrile before separation by liquid chromatography. The mass spectrome...
Rapid diagnosis of hypoglycin A intoxication in atypical myopathy of horses. Hypoglycin A (2-amino-3-(2-methylidenecyclopropyl)propanoic acid) is the plant toxin shown to cause atypical myopathy in horses. It is converted in vivo to methylenecyclopropyl acetic acid, which is transformed to a coenzyme A ester that subsequently blocks beta oxidation of fatty acids. Methylenecyclopropyl acetic acid is also conjugated with carnitine and glycine. Acute atypical myopathy may be diagnosed by quantifying the conjugates of methylenecyclopropyl acetic acid plus a selection of acyl conjugates in urine and serum. We describe a new mass spectrometric method for sample volumes of <0...
In vivo and in vitro metabolism of the designer anabolic steroid furazadrol in thoroughbred racehorses. Furazadrol ([1',2']isoxazolo[4',5':2,3]-5α-androstan-17β-ol) is a designer anabolic androgenic steroid that is readily available via the internet. It contains an isoxazole fused to the steroid A-ring which offers metabolic stability and noteworthy anabolic activity raising concerns over the potential for abuse of this compound in equine sports. The metabolism of furazadrol was studied by in vivo and in vitro methods for the first time. Urinary furazadrol 17-sulfate and furazadrol 17-glucuronide metabolites were detected in vivo after a controlled administration and compared with syntheticall...