Topic:Biochemistry
The study of biochemistry in horses encompasses the chemical processes and substances that occur within equine organisms. This field investigates the molecular interactions and pathways that are fundamental to horse physiology, including metabolism, enzyme activity, and genetic expression. Key areas of interest include the examination of metabolic disorders, nutrient absorption, and the biochemical basis of muscle function and energy production. Researchers utilize biochemical analysis to understand health and disease mechanisms in horses, contributing to the development of diagnostic tools and therapeutic strategies. This page gathers peer-reviewed studies and scholarly articles that explore various biochemical processes and their implications for equine health and performance.
The effect of training load stress on salivary cortisol concentrations, health parameters and hematological parameters in horses. The performance of sport horses is conditioned not only by the quality of its gene pool, but also by a large number of external factors. The most dominant being nutrition, quality of breeding, level of zootechnical care and the quality of the sports rider and coach. Important factor is the process of individuals' adaptation to the training load occurring during the training itself. This study was focused on the analysis of salivary cortisol levels as well as hematological and biochemical blood parameters in relation to load to which the tested horses were subjected. In the study 14 horses of s...
Pharmacokinetic modelling of orally administered cannabidiol and implications for medication control in horses. Cannabidiol (CBD) products gain increasing popularity amongst animal owners and veterinarians as an alternative remedy for treatment of stress, inflammation or pain in horses. Whilst the use of cannabinoids is banned in equine sports, there is limited information available concerning CBD detection times in blood or urine. The aim of this study was to determine the pharmacokinetic properties of CBD following oral administration in the horse to assist doping control laboratories with interpreting CBD analytical results. Part 1: dose escalation study: Single oral administration of three escalatin...
Effect of dipotassium-ethylenediaminetetraacetic acid or lithium-heparin treatments and storage times on selected clinicopathologic analytes in equine synovial fluid. Sample processing methods and storage time affect the outcome of biochemical analysis. Objectives: We aimed to assess the effects of dipotassium-ethylenediaminetetraacetic acid (K2-EDTA) and lithium-heparin treatments and storage times on selected analytes in equine synovial fluid (SF). Conclusions: The analytes-except for TP-became unstable within a few hours postcollection. Lithium-heparin and K2-EDTA treatments significantly altered ALP, LDH, TNCCs, and pH but not the TP concentrations of equine SF. Studies establishing reference intervals for these analytes based on the anticoagulant used ...
Performance of a manually operated salad spinner centrifuge for serum separation in the healthy domestic horse (Equus caballus) and southern white rhinoceros (Ceratotherium simum). Field veterinarians and researchers studying wild species, such as the southern white rhinoceros, often work in remote areas with limited access to standard laboratory equipment, hindering the ability to measure serum analytes.
Objectives: The first objective was to produce an inexpensive, manually operated centrifuge that could accept standard laboratory tubes by modifying a consumer-grade salad spinner with low-cost materials. The second objective was to compare biochemistry analysis results obtained from equine and southern white rhinoceros serum separated by traditional laboratory and m...
Tissue Specific Distribution and Activation of Sapindaceae Toxins in Horses Suffering from Atypical Myopathy. Equine atypical myopathy is caused by hypoglycin A (HGA) and methylenecyclopropylglycine (MCPrG), the known protoxins of sycamore maple (Acer pseudoplatanus). Various tissues from five atypical myopathy cases were analyzed but only HGA was found. Whether deamination of MCPrG has already occurred in the intestine as the first stage of metabolization has not been investigated. Activation of the protoxins to methylenecyclopropylacetyl (MCPA)-CoA and methylenecyclopropylformyl (MCPF)-CoA, respectively, occurred mainly in the skeletal muscles, as evidenced by very high concentrations of MCPA-carnit...
Effect of Supplementary Feeding on Milk Volume, Milk Composition, Blood Biochemical Index, and Fecal Microflora Diversity in Grazing Yili Mares. Grazing is a common approach to rearing. We investigated the effects of supplementation during grazing on milk yield and composition, blood biochemistry, and fecal microflora in Yili horses. The control mares grazed normally, while those in groups I and II received 1 kg/d of concentrate and 1 kg/d of concentrate + 0.4 kg/d of coated FA, respectively. Milk volumes were significantly higher in groups I and II than in the control group, and among the previous two, milk volumes were significantly higher in group II than in group I. Milk fat, lactose, and protein levels were significantly higher in...
Pharmacokinetics of multiple oral doses of acetaminophen in equine neonates. To determine the pharmacokinetics and clinical safety of acetaminophen after oral administration of 40 mg/kg q 12 hours or 60 mg/kg q 24 hours for 14 days. Methods: 12 healthy light-breed neonatal foals. Methods: 6 foals received acetaminophen at 40 mg/kg q 12 hours and 6 foals received 60 mg/kg q 24 hours for 14 days. The study dates were January 31 to April 15, 2023. Physical examinations were performed daily. Plasma disposition of acetaminophen was determined after the first, mid-point drug administration. Hematology and biochemistry analysis was performed before the study, day 7, and the l...
First evidence of the incorporation of daprodustat and other hypoxia-inducible factor stabilizers into equine hair by passive transfer based on segmental quantitative analysis. Daprodustat is a hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) inhibitor and is used as an erythropoiesis stimulant for the treatment of anemia in humans. In general, administering daprodustat to horses will result in a lifetime ban from both equestrian sports and horseracing by the International Federation of Horseracing Authorities and the Fédération Équestre Internationale, respectively. To control the misuse/abuse of daprodustat, we conducted nasoesophageal administration of daprodustat (100 mg/day for 3 days) to three thoroughbred mares and the post-administration hair ...
Pharmacokinetics and plasma protein binding of a single dose of clodronate disodium are similar for juvenile sheep and horses. To determine the single-dose pharmacokinetics of clodronate disodium (CLO) in juvenile sheep and the plasma protein binding (PPB) of CLO in juvenile sheep and horses. Methods: 11 juvenile crossbred sheep (252 ± 6 days) for the pharmacokinetic study. Three juvenile crossbred sheep (281 ± 4 days) and 3 juvenile Quarter Horses (599 ± 25 days) for PPB analysis. Methods: CLO concentrations were determined using liquid chromatography-mass spectrometry. Pharmacokinetic parameters were calculated by noncompartmental analysis from plasma samples obtained at 0, 0.5, 1, 3, 6, 12, 24, 48, and 72 hours ...
Pharmacokinetics and tolerability of multiple-day oral dosing of mycophenolate mofetil in healthy horses. Additional efficacious immunomodulatory treatment is needed for the management of immune-mediated disease in horses. Mycophenolate mofetil (MMF) is an immunosuppressive drug that warrants assessment as a viable therapeutic agent for horses. Objective: To evaluate the pharmacokinetics (PK) of multiple-day oral dosing of MMF in healthy horses and to determine the tolerability of this dosing regimen. Methods: Six healthy Standardbred mares. Methods: Horses received MMF 10 mg/kg PO q12h for 7 days in the fed state. Serial sampling was performed over 12 hours on Days 1 and 7 with trough sampl...
Assessment of calcium, phosphorus, magnesium, vitamin D and PTH levels in sera of lame horses. Minerals play vital roles in physiologic processes. Calcium, phosphorus and magnesium are common minerals. Secretion, absorption and homeostasis of these minerals are affected by associations between the active vitamin D and parathyroid hormone (PTH). The aim of this study was to assess concentrations of vitamin D, PTH and minerals, such as calcium, phosphorus and magnesium in horse sera, as well as associations of these values with lameness in horses. In the references, the reasons for lameness can be deficiency and imbalance of minerals, and clinical observations also confirm this and there ...
A hydrophobic deep eutectic solvent-based vortex-assisted liquid-liquid microextraction applied for doping control of aromatase inhibitors from equine urine. Aromatase inhibitors (AIs) can indirectly cause increased testosterone in animals, which leads to the improvement of the athletic ability of horses. For the protection of horses and the consideration of fair competition, AIs were listed as prohibited drugs by the Federation Equestre Internationale (FEI). There were several disadvantages using traditional pretreatment methods before analyzing these drugs from biological samples. A rapid and green pretreatment method has been developed by utilizing the hydrophobic deep eutectic solvent (DES)-based vortex-assisted liquid-liquid microextraction (D...
Technical note: Cartilage imaging with sub-cellular resolution using a laboratory-based phase-contrast x-ray microscope. Microscopic imaging of cartilage is a key tool for the study and development of treatments for osteoarthritis. When cellular and sub-cellular resolution is required, histology remains the gold standard approach, albeit limited by the lack of volumetric information as well as by processing artifacts. Cartilage imaging with the sub-cellular resolution has only been demonstrated in the synchrotron environment. Objective: To provide a proof-of-concept demonstration of the capability of a laboratory-based x-ray phase-contrast microscope to resolve sub-cellular features in a cartilage sample. Meth...
Pharmacokinetics of acetaminophen after a single Oral administration of 20 or 40 mg/kg to 7-9 Day-old foals. Acetaminophen is utilized in human infants for pain management and fever. Neonatal foals might benefit from administration of acetaminophen but effective and safe dosage regimens for neonatal foals remains to be determined. Unassigned: The objective was to determine the plasma pharmacokinetics of acetaminophen following oral administration of a single dose of 20 mg/kg or 40 mg/kg to neonatal foals. A secondary objective was to evaluate any changes in hematology and biochemistry profiles. Unassigned: Randomized study. Unassigned: Eight clinically healthy 7-9-day old Quarter Horse foals (3 c...
Cardiac Biomarker Responses to Acute Exercise in Show Jumping Horses. Cardiac biomarkers are useful to identify cardiac muscle variations in human and equine medicine. The aim of this study was to investigate the acute effect of a bout of show jumping training on serum activity of cardiac and muscular biomarkers in healthy athletic horses to include cardiac troponin (cTnI), myoglobin (MB), aspartate amino transferase (AST), alanine amino transferase (ALT), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH). Serum samples were collected from seven Italian Saddle horses (three geldings and four mares; 10 ± 3 years; mean body weight 480 ±70 kg), regular...
Central and Peripheral Fatigue Evaluation during Physical Exercise in Athletic Horses by Means of Raman Spectroscopy. The evaluation of the performance levels in athletic horses is of major importance to prevent sports injuries. Raman spectroscopy is an innovative technique that allows for a rapid evaluation of biomolecules in biological fluids. It also permits qualitative and quantitative sample analyses, which lead to the simultaneous determination of the components of the examined biological fluids. On the basis of this, the Raman spectroscopy technique was applied on serum samples collected from five Italian Saddle horses subjected to a standardized obstacle course preceded by a warm-up to evaluate the ap...
Screening and confirmation of recombinant human follistatin in equine plasma for doping control purposes. Recombinant human follistatin (rhFST) is a potential performance-enhancing agent owing to its stimulating effect on muscle growth. Administration of rhFST to athletes is prohibited in human sports by the World Anti-Doping Agency (WADA) and in horseracing according to Article 6 of the International Agreement on Breeding, Racing and Wagering published by the International Federation of Horseracing Authorities (IFHA). For effective control of the potential misuse of rhFST in flat racing, methods for screening and confirmatory analysis are required. This paper describes the development and validat...
Sex Hormone-Binding Globulin (SHBG) Maintains Proper Equine Adipose-Derived Stromal Cells (ASCs)’ Metabolic Functions and Negatively Regulates their Basal Adipogenic Potential. Sex hormone binding globulin (SHBG) deteriorated expression has been recently strongly correlated to increased level of circulating pro-inflammatory cytokines and insulin resistance, which are typical manifestations of equine metabolic syndrome (EMS). Despite previous reports demonstrated the potential therapeutic application of SHBG for liver-related dysfunctions, whether SHBG might modulate equine adipose-derived stem/stromal cells (EqASCs) metabolic machinery remains unknown. Therefore, we evaluated for the first time the impact of SHBG protein on metabolic changes in ASCs isolated from hea...
Travelling through the Natural Hierarchies of Type I Collagen with X-rays: From Tendons of Cattle, Horses, Sheep and Pigs. Type I collagen physiological scaffold for tissue regeneration is considered one of the widely used biomaterials for tissue engineering and medical applications. It is hierarchically organized: five laterally staggered molecules are packed within fibrils, arranged into fascicles and bundles. The structural organization is correlated to the direction and intensity of the forces which can be loaded onto the tissue. For a tissue-specific regeneration, the required macro- and microstructure of a suitable biomaterial has been largely investigated. Conversely, the function of multiscale structural i...
Evaluation of the effects of medium-term (57-day) omeprazole administration and of omeprazole discontinuation on serum gastrin and serum chromogranin A concentrations in the horse. Rebound gastric hyperacidity (RGH) secondary to hypergastrinemia has been suggested to contribute to the rapid recurrence of equine squamous gastric disease (ESGD) in horses after discontinuation of omeprazole. Objective: To evaluate changes in serum gastrin and chromogranin A (CgA) concentrations in response to medium-term (57-day) omeprazole treatment and after omeprazole discontinuation. Methods: Fourteen mature Thoroughbred racehorses in simulated race training. Methods: Horses received 2.28 g of oral omeprazole PO q24h for 57 days within a 61-day period, excluding a withholding period...
Applicability of 2,4-dinitrophenylhydrazine (DNPH) method of protein oxidative damage measurement in the seminal plasma of canine ( Canis lupus familiaris) and stallion ( Equus caballus). Seminal plasma (SP) proteins are responsible for sperm functional quality. Developing a reliable method to determine the degree of oxidative damage of these proteins is important for establishing semen fertilizing ability. The main aim of the study was to verify the applicability of protein carbonyl derivatives measurement in the SP of canine and stallion, using a method with 2,4-dinitrophenylhydrazine (DNPH). The research material consisted of ejaculates obtained from eight English Springer Spaniels, and from seven half-blood stallions during the breeding and non-breeding season. The content ...
Composition, architecture and biomechanical properties of articular cartilage in differently loaded areas of the equine stifle. Strategies for articular cartilage repair need to take into account topographical differences in tissue composition and architecture to achieve durable functional outcome. These have not yet been investigated in the equine stifle. Objective: To analyse the biochemical composition and architecture of three differently loaded areas of the equine stifle. We hypothesise that site differences correlate with the biomechanical characteristics of the cartilage. Methods: Ex vivo study. Methods: Thirty osteochondral plugs per location were harvested from the lateral trochlear ridge (LTR), the distal int...
High-throughput untargeted screening of biotherapeutic macromolecules in equine plasma by UHPLC-HRMS/MS: Application to monoclonal antibodies and Fc-fusion proteins for doping control. Many innovative biotherapeutics have been marketed in the last decade. Monoclonal antibodies (mAbs) and Fc-fusion proteins (Fc-proteins) have been developed for the treatment of diverse diseases (cancer, autoimmune diseases, and inflammatory disorders) and now represent an important part of targeted therapies. However, the ready availability of such biomolecules, sometimes characterized by their anabolic, anti-inflammatory, or erythropoiesis-stimulating properties, raises concerns about their potential misuse as performance enhancers for human and animal athletes. In equine doping control labo...
Clinical effects of a combination of phenylbutazone and omeprazole on chronic lameness in Mongolian horses. Phenylbutazone (PBZ) is the most commonly used drug to treat symptoms of lameness in horses; however, it is associated with adverse effects such as gastric ulcer syndrome (EGUS). Interestingly, many practitioners prescribe omeprazole (OME) concurrently with PBZ to prevent the development of EGUS. However, the efficacy and safety of this practice in Mongolian horses with chronic lameness remain unknown. Objective: To evaluate the clinical effects of a combination of PBZ and OME on chronic lameness in Mongolian horses. Methods: Randomised block experimental design. Methods: Eighteen Mongolian ho...
Lactate as the sole energy substrate induces spontaneous acrosome reaction in viable stallion spermatozoa. Equine spermatozoa appear to differ from spermatozoa of other species in using oxidative phosphorylation preferentially over glycolysis. However, there is little information regarding effects of different energy sources on measured parameters in equine spermatozoa. Objective: To determine the effect of three individual energy substrates, glucose, pyruvate, and lactate, on motion characteristics, membrane integrity, and acrosomal status of stallion spermatozoa. Methods: Freshly ejaculated stallion spermatozoa were incubated with combinations of glucose (5 mm), pyruvate (10 mm), and lactate (1...
Influence of Rho/ROCK inhibitor Y-27632 on proliferation of equine mesenchymal stromal cells. Mesenchymal stromal cells (MSC) isolated form bone marrow and adipose tissue are the most common cells used for cell therapy of orthopedic diseases. MSC derived from different tissues show differences in terms of their proliferation, differentiation potential and viability in prolonged cell culture. This suggests that there may be subtle differences in intracellular signaling pathways that modulate these cellular characteristics. The Rho/ROCK signaling pathway is essential for many cellular functions. Targeting of this pathway by the ROCK inhibitor Y-27632 has been shown to be beneficial for c...
Characterization of the Glycans of Equine κ-Casein. To study the protein-bound glycans of equine κ-casein, equine sodium caseinate was first obtained from raw mare's milk by acid precipitation and then fractionated by cation-exchange chromatography. The oligosaccharides of the obtained equine κ-casein were analyzed by RP-HPLC-UV-HRMS after β-elimination with simultaneous derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). In addition to the acidic tetrasaccharide derivative Neu5Ac-Gal-[Neu5Ac]-GalNAc-2PMP known from bovine κ-casein, the acidic pentasaccharide derivative Neu5Ac-Gal-[Gal-GlcNAc]-GalNAc-2PMP was identified as the most ab...
Identification and kinetics of microsomal and recombinant equine liver cytochrome P450 enzymes responsible for in vitro metabolism of omeprazole. In humans, omeprazole is metabolised by cytochrome P450 (CYP450) CYP2C19 and CYP3A4 with differences in CYP2C19 genotypes leading to variable response to therapy. Despite a wide use of omeprazole in horses with evidence of variable therapeutic efficiency, information regarding enzymatic metabolism is not currently available. This study aims to describe the in vitro kinetics of omeprazole metabolism and determine which enzyme(s) are responsible for omeprazole metabolism in horses. Omeprazole (0-800 uM) was incubated with liver microsomes and a panel of equine recombinant CYP450s (eq-rCYP). Meta...
Novel Expression of GLUT3, GLUT6 and GLUT10 in Equine Gluteal Muscle Following Glycogen-Depleting Exercise: Impact of Dietary Starch and Fat. Horses have a slow rate of muscle glycogen repletion relative to other species for unknown reasons. Our aim was to determine the expression of glucose transporters () and genes impacting GLUT4 expression and translocation in the gluteal muscle. Five fit Thoroughbred horses performed glycogen-depleting exercises on high-starch (HS, 2869 g starch/day) and low-starch, high-fat diets (LS-HF, 358 g starch/d) with gluteal muscle biopsies obtained before and after depletion and during repletion. Muscle glycogen declined by ≈30% on both diets with little increase during repletion on LS-HF. Transcrip...
A review of current chemistry, pharmacology, and regulation of endogenous anabolic steroids testosterone, boldenone, and nandrolone in horses. Anabolic androgenic steroids are synthetic substances related to the male sex hormones (androgens). These agents promote the growth of skeletal muscle (anabolic effects) and the development of male sexual characteristics (androgenic effects). Anabolic steroids have been illegally used for many years as performance-enhancing drugs in human, equine, and canine sports and as growth promoters in livestock reared to provide meat for human consumption. The analytical challenge to developing effective means of control within these fields has been exacerbated by the reported endogenous nature of some ...