Glycolysis is a metabolic pathway that involves the enzymatic breakdown of glucose to produce energy in the form of adenosine triphosphate (ATP) in horses. This process occurs in the cytoplasm of cells and is a critical component of cellular metabolism, providing energy for various physiological activities. Glycolysis consists of a series of ten enzyme-catalyzed reactions that convert glucose into pyruvate, with the concomitant production of ATP and nicotinamide adenine dinucleotide (NADH). In horses, glycolysis is particularly important during periods of intense exercise or when rapid energy production is required. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and physiological implications of glycolysis in equine muscle tissue and overall metabolic health.
Gong W, Ding W, Bou T, Shi L, Lin Y, Shi X, Wu H, Li Z, Dugarjaviin M, Bai D.Ferulic acid (FA), a natural antioxidant and major active component in Angelica sinensis, has beneficial effects on skeletal muscle health; however, its role in modulating muscle fiber type composition Mongolian horse remains unclear. In this study, we found that FA promotes the proliferation of Mongolian horse skeletal muscle satellite cell (MuSCs), upregulates the expression of fast-twitch muscle marker genes (e.g., MYH2), and downregulates the expression of slow-twitch markers (e.g., MYH7). RNA-seq revealed that FA activates the HIF-1 signaling pathway, significantly increasing PDK1 express...
Ortiz-Rodriguez JM, Bucci D, Tovar-Pascual L, Granata S, Spinaci M, Nesci S.Sperm metabolism consists of a sophisticated network of biochemical reactions and varies between species, resulting in different metabolic strategies for ATP production to maintain sperm functionality. ATP can be produced through glycolysis or in the mitochondria by oxidative phosphorylation (OXPHOS). Since OXPHOS is the predominant metabolic pathway in horses spermatozoa, various assessments of mitochondrial activity are used to evaluate fertility, utilizing techniques such as fluorescent probes analysed via microscopy or flow cytometry, and polarographic electrode assays to measure current f...
Takahashi K, Mukai K, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.Evidence suggests that positive pacing strategy improves exercise performance and fatigue tolerance in athletic events lasting 1-5 min. This study investigated muscle metabolic responses to positive and negative pacing strategies in Thoroughbred horses. Eight Thoroughbred horses performed 2 min treadmill running using positive (1 min at 110% maximal O uptake [V̇Omax], followed by 1 min at 90% V̇Omax) and negative (1 min at 90% V̇Omax, followed by 1 min at 110% V̇Omax) pacing strategies. The arterial-mixed venous O difference did not significantly differ between the two strategies. Pl...
Zhang X, Geng A, Cao D, Dugarjaviin M. Horses are susceptible to oxidative stress during strenuous endurance exercise, leading to muscle fatigue and damage. Mulberry leaf flavonoids (MLFs) possess significant antioxidant properties. However, the antioxidant efficacy of MLFs can be influenced by the extraction process, and their impact on HO-induced oxidative stress in equine skeletal muscle satellite cells (ESMCs) remains unexplored. Our study employed three extraction methods to obtain MLFs: ultrasound-assisted extraction (CEP), purification with AB-8 macroporous resin (RP), and n-butanol extraction (NB-EP). We assessed the prot...
Kruse CJ, Dieu M, Renaud B, François AC, Stern D, Demazy C, Burteau S, Boemer F, Art T, Renard P, Votion DM.Equine atypical myopathy (AM) is a severe environmental intoxication linked to the ingestion of protoxins contained in seeds and seedlings of the sycamore maple (Acer pseudoplatanus) in Europe. The toxic metabolites cause a frequently fatal rhabdomyolysis syndrome in grazing horses. Since these toxic metabolites can also be present in cograzing horses, it is still unclear as to why, in a similar environmental context, some horses show signs of AM, whereas others remain clinically healthy. Label-free proteomic analyses on the serum of 26 diseased AM, 23 cograzers, and 11 control horses were per...
Myćka G, Ropka-Molik K, Cywińska A, Szmatoła T, Stefaniuk-Szmukier M.Recent studies have shown that in Arabian horse muscle, long-term exercise-induced expression of genes related to fatty acid degradation and the downregulation of genes belonging to the glycolysis/gluconeogenesis and insulin signalling pathways. Long-lasting physical exertion may trigger the metabolism to switch the main energy source from carbohydrates to lipids due to higher caloric content. Objective: To describe the metabolism adaptation at the whole transcriptome of blood to endurance effort in Arabian horses. Methods: In vivo experiment. Methods: Venous blood samples from 10 Arabian hors...
Bou T, Ding W, Ren X, Liu H, Gong W, Jia Z, Zhang X, Dugarjaviin M, Bai D.Traditional Mongolian endurance training is an effective way to improve the athletic ability of the horse for endurance events and is widely used. This incorporates aerobic exercise and intermittent fasting and these altered physiologic conditions are associated with switches between muscle fibre types. Objective: To better understand the adaption of horse skeletal muscle to traditional Mongolian endurance training from muscle fibre characteristics and transcriptional levels and to explore possible molecular mechanisms associated with the endurance performance of horses. Methods: Before-after ...
Ramírez-Agámez L, Hernández-Avilés C, Ortíz I, Love CC, Varner DD, Hinrichs K.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...
Zhang J, Zhao L, Fu Y, Liu F, Wang Z, Li Y, Zhao G, Sun W, Wu B, Song Y, Li S, Hao C, Wuyun B, Wu R, Liu M, Cao G, Nashun B, Surani MA, Sun Q, Bao S....The mule is the interspecific hybrid of horse and donkey and has hybrid vigor in muscular endurance, disease resistance, and longevity over its parents. Here, we examined adult fibroblasts of mule (MAFs) compared with the cells from their parents (donkey adult fibroblasts and horse adult fibroblasts) (each species has repeated three independent individuals) in proliferation, apoptosis, and glycolysis and found significant differences. We subsequently derived mule, donkey, and horse doxycycline (Dox)-independent induced pluripotent stem cells (miPSCs, diPSCs, and hiPSCs) from three independent ...
Valberg SJ, Williams ZJ, Finno CJ, Schultz A, Velez-Irizarry D, Henry ML, Gardner K, Petersen JL.Both type 1 (PSSM1) and type 2 polysaccharide storage myopathy (PSSM2) are characterised by aggregates of abnormal polysaccharide in skeletal muscle. Whereas the genetic basis for PSSM1 is known (R309H GYS1), the cause of PSSM2 in Quarter Horses (PSSM2-QH) is unknown and glycogen concentrations not defined. Objective: To characterise the histopathological and biochemical features of PSSM2-QH and determine if an associated monogenic variant exists in genes known to cause glycogenosis. Methods: Retrospective case control. Methods: Sixty-four PSSM2-QH, 30 PSSM1-QH and 185 control-QH were identifi...
Miglio A, Maslanka M, Di Tommaso M, Rocconi F, Nemkov T, Buehler PW, Antognoni MT, Spitalnik SL, D'Alessandro A.The use of omics technologies in human transfusion medicine has improved our understanding of the red blood cell (RBC) storage lesion(s). Despite significant progress towards understanding the storage lesion(s) of human RBCs, a comparison of basal and post-storage RBC metabolism across multiple species using omics technologies has not yet been reported, and is the focus of this study. Blood was collected in a standard bag system (CPD-SAG-Mannitol) from dogs (n=8), horses, bovines, and donkeys (n=6). All bags were stored at 4°C for up to 42 days (i.e., the end of the shelf life in Italian vete...
Gupta S, Vohra S, Sethi K, Gupta S, Bera BC, Kumar S, Kumar R.High cytotoxicity and increasing resistance reports of existing chemotherapeutic agents against T. evansi have raised the demand for novel, potent, and high therapeutic index molecules for the treatment of surra in animals. In this regard, repurposing approach of drug discovery has provided an opportunity to explore the therapeutic potential of existing drugs against new organism. With this objective, the macrocyclic lactone representative, ivermectin, has been investigated for the efficacy against T. evansi in the axenic culture medium. To elucidate the potential target of ivermectin in T. ev...
Han L, Lan T, Lu Y, Zhou M, Li H, Lu H, Wang Q, Li X, Du S, Guan C, Zhang Y, Sahu SK, Qian P, Zhang S, Zhou H, Guo W, Chai H, Wang S, Liu Q, Liu H....The evolution of parasites is often directly affected by the host's environment. Studies on the evolution of the same parasites in different hosts are of great interest and are highly relevant to our understanding of divergence. Methods: Here we performed whole-genome sequencing of Parascaris univalens from different Equus hosts (horses, zebras and donkeys). Phylogenetic and selection analyses were performed to study the divergence and adaptability of P. univalens. Results: At the genetic level, multiple lines of evidence indicate that P. univalens is mainly separated into two clades (horse-de...
Peña FJ, O'Flaherty C, Ortiz Rodríguez JM, Martín Cano FE, Gaitskell-Phillips G, Gil MC, Ortega Ferrusola C.Significance: Proper functionality of the spermatozoa depends on the tight regulation of their redox status; at the same time these cells are highly energy demanding and in the energetic metabolism, principally in the electron transport chain in the mitochondria, reactive oxygen species are continuously produced, in addition to that observed in the Krebs cycle and during the β-oxidation of fatty acids. Recent Advances: In addition, in glycolysis, elimination of phosphate groups from glyceraldehyde 3-phosphate and dihydroxyacetone phosphate results in the byproducts glyoxal (G) and methylglyox...
Lanier CJ, Taintor JS, Christopherson PW, Spangler EA.Acidemia in sick or injured horses is often due to lactic acid accumulation. Alterations in platelet function and hemostasis are among numerous deleterious effects caused by decreased physiologic pH. Objective: We aimed to evaluate the effect of hyperlactatemia and resultant acidemia on platelet aggregation in equine whole blood using impedance aggregometry. Methods: Platelet aggregation was measured using the Multiplate analyzer in whole blood from 34 healthy horses at baseline and after in vitro addition of lactic acid to adjust the pH. Platelet aggregation of each sample was quantified by t...
Mukai K, Kitaoka Y, Takahashi Y, Takahashi T, Takahashi K, Ohmura H.We investigated whether moderate-intensity training of horses in moderate hypoxia for 4 weeks elicits greater adaptations in exercise performance, aerobic capacity, and glycolytic/oxidative metabolism in skeletal muscle compared to normoxic training. In a randomized crossover study design, seven untrained Thoroughbred horses (5.9 ± 1.1 years, 508 ± 9 kg) completed 4 weeks (3 sessions/week) of two training protocols consisting of 3-min cantering at 70% of maximal oxygen consumption ( ) in hypoxia (HYP; F O = 14.7%) and normoxia (NOR; F O = 21.0%) with a 4-month washout period....
Henry ML, Velez-Irizarry D, Pagan JD, Sordillo L, Gandy J, Valberg SJ.Horses have one of the highest skeletal muscle oxidative capacities amongst mammals, which, combined with a high glycolytic capacity, could perturb redox status during maximal exercise. We determined the effect of 30 d of oral coenzyme Q10 and N-acetyl-cysteine supplementation (NACQ) on muscle glutathione (GSH), cysteine, ROS, and coenzyme Q10 concentrations, and the muscle proteome, in seven maximally exercising Thoroughbred horses using a placebo and randomized cross-over design. Gluteal muscle biopsies were obtained the day before and 1 h after maximal exercise. Concentrations of GSH, cyste...
The study investigates the changes in meat organoleptic characteristics and sarcoplasmic proteins of 3 horse muscles during aging. Longissimus lumborum (LL), semimembranosus (SM) and semitendinosus (ST) muscles, were removed from 12 Italian Heavy Draft Horse carcasses and aged for 1, 3, 6, 9 and 14 days. The lowest values of hardness and chewiness were found in LL muscle. During aging, a decrease of hardness was observed in ST muscle reaching the lowest value at 14 days. 2DE revealed a decrease of 15 sarcoplasmic protein spots in all muscles. Muscle-differences were found at 14 days. An inc...
A deep knowledge on metabolic response of athlete horse to exercise is of paramount importance for the development of optimal training programs to attain equilibrium between good performance and animal welfare. This study investigated the dynamic change of metabolic, clotting times and peripheral indices of central fatigue in horses competing in an official 44 km endurance race. From 6 horses blood samples were collected at rest (T), within 5 minutes from the end of race (T), after 30, 60 minutes after the end of race (T and T) to investigate the values of blood lactate, glucose, platelet...
Vercelli C, Tursi M, Miretti S, Giusto G, Gandini M, Re G, Valle E.Laminitis is one of the most devastating diseases in equine medicine, and although several etiopathogenetic mechanisms have been proposed, few clear answers have been identified to date. Several lines of evidence point towards its underlying pathology as being metabolism-related. In the carbonyl stress pathway, sugars are converted to methylglyoxal (MG)-a highly reactive α-oxoaldehyde, mainly derived during glycolysis in eukaryotic cells from the triose phosphates: D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. One common hypothesis is that MG could be synthesized during the dig...
Peña FJ, Ortiz-Rodríguez JM, Gaitskell-Phillips GL, Gil MC, Ortega-Ferrusola C, Martín-Cano FE.An overview of the sperm metabolism is presented; using the stallion as a model we review glycolysis, Krebs Cycle and oxidative phosphorylation, paying special attention to the interactions among them. In addition, metabolism implies a series of coordinated oxidation-reduction reactions and in the course of these reactions reactive oxygen species (ROS) and reactive oxoaldehydes are produced ; the electron transport chain (ETC) in the mitochondria is the main source of the anion superoxide and hydrogen peroxide, while glycolysis produces 2-oxoaldehydes such as methylglyoxal as byproducts; due t...
Ohmura H, Mukai K, Takahashi Y, Takahashi T.Thoroughbreds have high maximal oxygen consumption and show hypoxemia and hypercapnia during intense exercise, suggesting that the peripheral environment in skeletal muscle may be severe. Changes in metabolites following extreme alterations in the muscle environment in horses after exercise may provide useful evidence. We compared the muscle metabolites before and after supramaximal exercise to fatigue in horses. Six well-trained horses ran until exhaustion in incremental exercise tests. Biopsy samples were obtained from the gluteus medius muscle before and immediately after exercise for capil...
Ortiz-Rodríguez JM, Martín-Cano FE, Gaitskell-Phillips GL, Silva A, Ortega-Ferrusola C, Gil MC, Peña FJ.Energy metabolism in spermatozoa is complex and involves the metabolism of carbohydrate fatty acids and amino acids. The ATP produced in the electron transport chain in the mitochondria appears to be crucial for both sperm motility and maintaining viability, whereas glycolytic enzymes in the flagella may contribute to ATP production to sustain motility and velocity. Stallion spermatozoa seemingly use diverse metabolic strategies, and in this regard, a study of the metabolic proteome showed that Gene Ontology terms and Reactome pathways related to pyruvate metabolism and the Krebs cycle were pr...
de Meeûs d'Argenteuil C, Boshuizen B, Oosterlinck M, van de Winkel D, De Spiegelaere W, de Bruijn CM, Goethals K, Vanderperren K, Delesalle CJG.Equine bioenergetics have predominantly been studied focusing on glycogen and fatty acids. Combining omics with conventional techniques allows for an integrative approach to broadly explore and identify important biomolecules. Friesian horses were aquatrained (n = 5) or dry treadmill trained (n = 7) (8 weeks) and monitored for: evolution of muscle diameter in response to aquatraining and dry treadmill training, fiber type composition and fiber cross-sectional area of the M. pectoralis, M. vastus lateralis and M. semitendinosus and untargeted metabolomics of the M. pectoralis and M. vastus late...
Lee HY, Kim JY, Kim KH, Jeong S, Cho Y, Kim N.Horses have been studied for exercise function rather than food production, unlike most livestock. Therefore, the role and characteristics of tissue landscapes are critically understudied, except for certain muscles used in exercise-related studies. In the present study, we compared RNA-Seq data from 18 Jeju horse skeletal muscles to identify differentially expressed genes (DEGs) between tissues that have similar functions and to characterize these differences. We identified DEGs between different muscles using pairwise differential expression (DE) analyses of tissue transcriptome expression d...
Sánchez-Calabuig MJ, Fernández-González R, Hamdi M, Smits K, López-Cardona AP, Serres C, Macías-García B, Gutiérrez-Adán A.Equine embryos exhibit an unusual pattern of glucose tolerance in vitro and are currently cultured in hyperglycaemic conditions. Objective: Our main objective was to analyse the effect of different glucose concentrations on in vitro-produced equine embryo development and quality. Methods: Experiments comparing in vitro and in vivo produced embryos. Methods: Oocytes (n = 641) were collected from post-mortem ovaries, matured in vitro and fertilised by intracytoplasmic sperm injection (ICSI). Embryo culture was divided from Day 0 to Day 4 and from Day 4 to Day 9 in three groups: 5-10 (5 and 10...
Aitken RJ, Gregoratos D, Kutzera L, Towney E, Lin M, Wilkins A, Gibb Z.MTT is widely used in biology as a probe for cell viability by virtue of its ability to generate deposits of insoluble formazan at sites of intense oxidoreductase activity. This response is generally held to reflect mitochondrial redox activity; however, extra-mitochondrial MTT reduction has also been recorded in certain cell types. Given this background, we set out to determine the major sites of formazan deposition in mammalian spermatozoa. In the mouse, most MTT reduction took place within the extensive mitochondrial gyres, with a single minor site of formazan deposition on the sperm head. ...
Wang W, Mukai K, Takahashi K, Ohmura H, Takahashi T, Hatta H, Kitaoka Y.The aim of this study was to investigate effects of short-term hypoxic training on lactate metabolism in the gluteus medius muscle of Thoroughbreds. Using crossover design (3 months washout), eight Thoroughbred horses were trained for 2 weeks in normoxia (F O = 21%) and hypoxia (F O = 18%) each. They ran at 95% maximal oxygen consumption (V̇O ) on a treadmill inclined at 6% for 2 min (3 days/week) measured under normoxia. Before and after each training period, all horses were subjected to an incremental exercise test (IET) under normoxia. Following the 2-week trainings, V̇O in IET ...
Lewis N, Hinrichs K, Leese HJ, McG Argo C, Brison DR, Sturmey R.Horses are one of the few species, beside humans, in which assisted reproductive technology has important clinical applications. Furthermore, the horse can serve as a valuable model for the study of comparative reproductive biology. Here we present the first comprehensive characterisation of energy metabolism and mitochondrial efficiency in equine cumulus-oocyte complexes (COCs) during in vitro maturation (IVM), as determined using a combination of non-invasive consumption and release assays and mitochondrial function analysis. These data reveal notable species-specific differences in the rate...
da Silveira BP, Gressler LT, Cargnelutti JF, Bordin AI, de Vargas AC.The ability of Rhodococcus equi to survive in macrophages and cause pneumonia in foals depends on vapA and rhbC genes, which produce the virulence-associated protein A (VapA) and the rhequichelin siderophore, respectively. Virulent R. equi acquires Fe from transferrin by unknown mechanisms. Our objectives were to determine the role of GAPDH in Fe homeostasis, to further characterize GAPDH, rhbC, and vapA expression under iron homeostasis, and to document the occurrence of rhbC gene in R. equi isolates. Therefore, vapA + R. equi was cultured under excessive, physiologic, and restricted iron c...
Gibb Z, Lambourne SR, Aitken RJ.The relationship between stallion fertility and oxidative stress remains poorly understood. The purpose of this study was to identify criteria for thoroughbred fertility assessment by performing a logistical regression analysis using "dismount" sperm parameters as predictors and weekly per-cycle conception rate as the dependent variable. Paradoxically, positive relationships between fertility and oxidative stress were revealed, such that samples that produced pregnancies exhibited higher rates of 8-hydroxy-2'-deoxyguanosine release (1490.2% vs. 705.5 pg/ml/24 h) and lower vitality (60.5% vs. 6...
Plaza Davila M, Martin Muñoz P, Tapia JA, Ortega Ferrusola C, Balao da Silva C C, Peña FJ.Mitochondria have been proposed as the major source of reactive oxygen species in somatic cells and human spermatozoa. However, no data regarding the role of mitochondrial ROS production in stallion spermatozoa are available. To shed light on the role of the mitochondrial electron transport chain in the origin of oxidative stress in stallion spermatozoa, specific inhibitors of complex I (rotenone) and III (antimycin-A) were used. Ejaculates from seven Andalusian stallions were collected and incubated in BWW media at 37 °C in the presence of rotenone, antimycin-A or control vehicle. Incubation...
Rome LC, Sosnicki AA, Goble DO.1. To explore how maximum velocity of shortening (Vmax) of fibres varies within one muscle and how Vmax varies with body size, we measured Vmax of muscle fibres from soleus muscle of a large animal, the horse. 2. Vmax was determined by the slack test on skinned single muscle fibres at 15 degrees C during maximal activation (pCa = 5.2). The fibre type was subsequently determined by a combination of single-cell histochemistry and gel electrophoresis of the myosin light chains. 3. Vmax values for the type I, IIA and IIB muscle fibres were 0.33 +/- 0.04 muscle lengths/s (ML/s) (+/- S.E.M., n = 6),...
McCue ME, Valberg SJ, Miller MB, Wade C, DiMauro S, Akman HO, Mickelson JR.Polysaccharide storage myopathy (PSSM) is a novel glycogenosis in horses characterized by abnormal glycogen accumulation in skeletal muscle and muscle damage with exertion. It is unlike glycogen storage diseases resulting from known defects in glycogenolysis, glycolysis, and glycogen synthesis that have been described in humans and domestic animals. A genome-wide association identified GYS1, encoding skeletal muscle glycogen synthase (GS), as a candidate gene for PSSM. DNA sequence analysis revealed a mutation resulting in an arginine-to-histidine substitution in a highly conserved region of G...
Westhoff D, Kamp G.Evidence is provided that the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase is covalently linked to the fibrous sheath. The fibrous sheath is a typical structure of mammalian spermatozoa surrounding the axoneme in the principal piece of the flagellum. More than 90% of boar sperm glyceraldehyde 3-phosphate dehydrogenase activity is sedimented after cell disintegration by centrifugation. Detergents, different salt concentrations or short term incubation with chymotrypsin do not solubilize the enzyme, whereas digestion with trypsin or elastase does. Short term incubation with trypsin...
Binns MM, Boehler DA, Lambert DH.One hundred and eighty-nine Thoroughbred horses that had won Graded Stakes races in North America were genotyped with the Illumina Equine SNP50 bead chip. Association tests using PLINK to determine whether any SNPs were associated with optimum racing distance (7 furlongs and under compared to 8-10 furlongs) identified a locus on ECA18 that was statistically significant (-log 10 EMP2=1.63) at the genome-wide level following permutation analysis (10,000 permutations). Bioinformatic analysis revealed that the two ECA18 SNPs with the highest statistical significance spanned the MSTN (myostatin) lo...
Peña FJ, Ortiz-Rodríguez JM, Gaitskell-Phillips GL, Gil MC, Ortega-Ferrusola C, Martín-Cano FE.An overview of the sperm metabolism is presented; using the stallion as a model we review glycolysis, Krebs Cycle and oxidative phosphorylation, paying special attention to the interactions among them. In addition, metabolism implies a series of coordinated oxidation-reduction reactions and in the course of these reactions reactive oxygen species (ROS) and reactive oxoaldehydes are produced ; the electron transport chain (ETC) in the mitochondria is the main source of the anion superoxide and hydrogen peroxide, while glycolysis produces 2-oxoaldehydes such as methylglyoxal as byproducts; due t...
Plancade S, Clark A, Philippe C, Helbling JC, Moisan MP, Esquerré D, Le Moyec L, Robert C, Barrey E, Mach N.An integrated analysis of gut microbiota, blood biochemical and metabolome in 52 endurance horses was performed. Clustering by gut microbiota revealed the existence of two communities mainly driven by diet as host properties showed little effect. Community 1 presented lower richness and diversity, but higher dominance and rarity of species, including some pathobionts. Moreover, its microbiota composition was tightly linked to host blood metabolites related to lipid metabolism and glycolysis at basal time. Despite the lower fiber intake, community type 1 appeared more specialized to produce ace...
Davila MP, Muñoz PM, Bolaños JM, Stout TA, Gadella BM, Tapia JA, da Silva CB, Ferrusola CO, Peña FJ.To investigate the hypothesis that oxidative phosphorylation is a major source of ATP to fuel stallion sperm motility, oxidative phosphorylation was suppressed using the mitochondrial uncouplers CCCP and 2,4,-dinitrophenol (DNP) and by inhibiting mitochondrial respiration at complex IV using sodium cyanide or at the level of ATP synthase using oligomycin-A. As mitochondrial dysfunction may also lead to oxidative stress, production of reactive oxygen species was monitored simultaneously. All inhibitors reduced ATP content, but oligomycin-A did so most profoundly. Oligomycin-A and CCCP also sign...
Rivero JL, Ruz A, Martí-Korff S, Estepa JC, Aguilera-Tejero E, Werkman J, Sobotta M, Lindner A.This study examined the effects of the intensity and duration of exercise on the nature and magnitude of training adaptations in muscle of adolescent (2-3 yr old) racehorses. Six thoroughbreds that had been pretrained for 2 mo performed six consecutive conditioning programs of varying lactate-guided intensities [velocities eliciting blood lactate concentrations of 2.5 mmol/l (v2.5) and 4 mmol/l (v4), respectively] and durations (5, 15, 25 min). Pre- and posttraining gluteus muscle biopsies were analyzed for myosin heavy chain content, fiber-type composition, fiber size, capillarization, and fi...
Gibb Z, Aitken RJ.In vitro sperm storage is a necessary part of many artificial insemination or in vitro fertilization regimes for many species, including the human and the horse. In many situations spermatozoa are chilled to temperatures between 4 and 10°C for the purpose of restricting the metabolic rate during storage, in turn, reducing the depletion of ATP and the production of detrimental by-products such as reactive oxygen species (ROS). Another result of lowering the temperature is that spermatozoa may be "cold shocked" due to lipid membrane phase separation, resulting in reduced fertility. To overcome ...
Ropka-Molik K, Stefaniuk-Szmukier M, Z Ukowski K, Piórkowska K, Bugno-Poniewierska M.It has been found that Arabian and Thoroughbred horses differ in muscle fiber structure and thus in physiological changes occurring in muscles during exercise. The aim of the present study was to identify the global gene expression modifications that occur in skeletal muscle following a training regime to prepare for flat racing. Whole transcriptomes of muscle (gluteus medius) were compared between three time points of tissue collection: T (untrained horses), T (horses after intense gallop phase), and T (horses at the end of racing season), 23 samples in total. The numerous groups of exercise-...
Meyers S, Bulkeley E, Foutouhi A.The biological nature of age-related declines in fertility in males of any species, including stallions, has been elusive. In horses, the economic costs to the breeding industry are frequently extensive. Mitochondrial function in ejaculated sperm, which is essential for sperm motility, is reflected by adenosine triphosphate production, mitochondrial oxidative efficiency and production of reactive oxygen species, and that this balance may become compromised in ageing stallions and during the process of cryopreservation. This presentation will focus on mitochondrial integrity and function as an ...
Armstrong RB, Essén-Gustavsson B, Hoppeler H, Jones JH, Kayar SR, Laughlin MH, Lindholm A, Longworth KE, Taylor CR, Weibel ER.The purpose of this study was to describe the relationships between 16 physiological, biochemical, and morphological variables presumed to relate to the oxidative capacity in quadriceps muscles or muscle parts in Standardbred horses. The variables included O2 delivery (blood flow) and mean capillary transit time (MTT) during treadmill locomotion at whole animal maximal O2 consumption (VO2max, 134 +/- 2 ml.min-1 x kg-1), capillary density and capillary-to-fiber ratio, myoglobin concentration, oxidative enzyme activities, glycolytic enzyme activities, fiber type populations, and fiber size. Thes...
Votion DM, Fraipont A, Goachet AG, Robert C, van Erck E, Amory H, Ceusters J, de la Rebière de Pouyade G, Franck T, Mouithys-Mickalad A, Niesten A....Limited information exists about the muscle mitochondrial respiratory function changes that occur in horses during an endurance season. Objective: To determine effects of training and racing on muscle oxidative phosphorylation (OXPHOS) and electron transport system (ETS) capacities in horses with high resolution respirometry (HRR). Methods: Mitochondrial respiration was measured in microbiopsies taken from the triceps brachii (tb) and gluteus medius (gm) muscles in 8 endurance horses (7 purebred Arabians and 1 crossbred Arabian) before training (T0), after two 10 week training periods (T1, T2)...
Snow DH, Harris RC, Gash SP.Four thoroughbred horses performed 4 gallops (G1-G4) with intervals of 5 min. With one exception, gallops were sustained at maximal speed over 620 m. Muscle biopsy samples of the middle gluteal and brachiocephalicus were taken before, during, and after exercise and assayed for ATP and intermediary metabolites. The results showed a major involvement of the brachiocephalicus, in addition to the middle gluteal, during galloping. In three horses, who were clearly fatigued, muscle ATP decreased by up to 50% by the end of G4. This was matched by an equal rise in inosine 5'-monophosphate. Pronounced ...
Harvey JW.Deficiencies of enzymes involved in erythrocyte metabolism can have significant effects on erythrocyte function and survival. Animals with pyruvate kinase (PK) or phosphofructokinase (PFK) deficiencies have shortened erythrocyte life spans and regenerative anemia. PK-deficient dogs (but not PK-deficient cats) develop progressive myelofibrosis and osteosclerosis of bone marrow and hemochromatosis and cirrhosis of the liver. PFK-deficient dogs have sporadic episodes of hyperventilation-induced intravascular hemolysis and hemoglobinuria. Cytochrome b5 reductase (Cb5R) deficiency in dogs and cats ...
Swegen A, Lambourne SR, Aitken RJ, Gibb Z.Media used for equine sperm storage often contain relatively high concentrations of glucose, even though stallion spermatozoa preferentially utilize oxidative phosphorylation (OXPHOS) over glycolysis to generate ATP and support motility. Rosiglitazone is an antidiabetic compound that enhances metabolic flexibility and glucose utilization in various cell types, but its effects on sperm metabolism are unknown. This study investigated the effects of rosiglitazone on stallion sperm function in vitro, along with the possible role of AMP-activated protein kinase (AMPK) in mediating these effects. Sp...
Harris RC, Marlin DJ, Snow DH.To define the metabolic response to maximal exercise in the thoroughbred horse under field conditions, muscle biopsies and venous blood samples were taken from five horses after a single 800-m gallop and from four horses after a single 2,000-m gallop. Muscle and blood samples were also collected during 60 min of recovery. After exercise muscle ATP contents were decreased by 30 +/- 7 (SD) and 47 +/- 3% after the 800- and 2,000-m gallops, respectively. As indicators of purine catabolism, ammonia and uric acid increased in plasma, the accumulation being greater after the 2,000-m gallop. Blood amm...
Gunn HM.Histochemical profiles of individual muscle fibres were established using myosin adenosine triphosphatase (myosin ATPase), succinate dehydrogenase (SDHase), and glycogen phosphorylase (GPase) reactions in three muscles (semitendinosus, diaphragm, and pectoralis transversus) of the horse and dog. The major histochemical difference between fibres lies in their myosin ATPase activity; fibres can be subdivided into those with a high and those with a low activity. In horse muscle, all fibres have a high activity of GPase. In the diaphragm and pectoralis transversus, all fibres have a high SDHase ac...
Bousfield GR, Sugino H, Ward DN.The beta subunits of equine lutropin and equine chorionic gonadotropin were incubated in 0.013 N HCl for 30 min at 110 degrees C and separated into two fragments by reverse-phase high performance liquid chromatography. The amino acid and carbohydrate compositions of both fragments from each subunit were analyzed. The results demonstrated that equine lutropin-beta has a glycosylated COOH-terminal extension that differs only in carbohydrate composition from the COOH-terminal portion of equine chorionic gonadotropin-beta. This is the first demonstration of a glycosylated COOH-terminal extension i...
Essén-Gustavsson B, Lindholm A.Muscle biopsies were taken from the middle gluteus muscle of 36 Standardbred horses. Twelve of the horses were inactive, while 24 were actively trained and raced. Twelve of the trained horses were moderate performers, with a mean racing time of 1 min 21 secs per km (741 m/min) and the other 12 were excellent performers, with a mean racing time of 1 min 16 secs per km (789 m/min). The percentage and mean area of Type I fibres were similar in all three groups of horses. Marked differences were found among the subgroups of Type II fibres. The well-trained horses had a higher proportion of Type II...
Williams TM, Dobson GP, Mathieu-Costello O, Morsbach D, Worley MB, Phillips JA.To establish a skeletal muscle profile for elite sprinters, we obtained muscle biopsy samples from the vastus lateralis, gastrocnemius and soleus of African cheetahs (Acinonyx jubatus). Muscle ultrastructure was characterized by the fiber type composition and mitochondrial volume density of each sample. Maximum enzyme activity, myoglobin content and mixed fiber metabolite content were used to assess the major biochemical pathways. The results demonstrate a preponderance of fast-twitch fibers in the locomotor muscles of cheetahs; 83% of the total number of fibers examined in the vastus laterali...
Jones JH, Lindstedt SL.Body size fundamentally affects maximal locomotor performance in mammals. Comparisons of performances of different-sized animals yield different results if made using relative, rather than absolute scales. Absolute speed may be a reasonable way to evaluate the locomotor performance of an animal that must escape predators in real time. However, comparisons of metabolic power in animals of different size can only be made meaningfully on a mass-specific basis. Numerous factors associated with the mechanics, energetics, and storage of elastic energy during locomotion change with body size, which r...
Eto D, Yamano S, Mukai K, Sugiura T, Nasu T, Tokuriki M, Miyata H.We hypothesize that high intensity training for Thoroughbred horses that have been subjected to conventional training could further improve the metabolic properties of the middle gluteal muscle. Nine well-trained horses were subjected to high intensity (80-100% Vdot;O(2)max, 5 minx2) training for 12 weeks. Biopsy samples were obtained from the muscle before and after 4 and 12 weeks of training. Three of the 9 horses did not complete the training programme. In the remaining 6 horses, activities of succinic dehydrogenase (SDH), phosphofructokinase (PFK) and 3-hydroxy acyl CoA dehydrogenase (HAD)...
de Meeûs d'Argenteuil C, Boshuizen B, Oosterlinck M, van de Winkel D, De Spiegelaere W, de Bruijn CM, Goethals K, Vanderperren K, Delesalle CJG.Equine bioenergetics have predominantly been studied focusing on glycogen and fatty acids. Combining omics with conventional techniques allows for an integrative approach to broadly explore and identify important biomolecules. Friesian horses were aquatrained (n = 5) or dry treadmill trained (n = 7) (8 weeks) and monitored for: evolution of muscle diameter in response to aquatraining and dry treadmill training, fiber type composition and fiber cross-sectional area of the M. pectoralis, M. vastus lateralis and M. semitendinosus and untargeted metabolomics of the M. pectoralis and M. vastus late...
Yamano S, Eto D, Sugiura T, Kai M, Hiraga A, Tokuriki M, Miyata H.To determine the effect of growth and training on metabolic properties in muscle fibers of the gluteus medius muscle in adolescent Thoroughbred horses. Methods: Twenty 2-year-old Thoroughbreds. Methods: Horses were randomly assigned to 2 groups. Horses in the training group were trained for 16 weeks, and control horses were kept on pasture without training. Samples were obtained by use of a needle-biopsy technique from the middle gluteus muscle of each horse before and after the training period. Composition and oxidative enzyme (succinic dehydrogenase [SDHI) activity of each fiber type were de...
Harris RC, Marlin DJ, Snow DH, Harkness RA.The effect of 2 min treadmill exercise, at speeds of 6-12 m.s-1 on an incline of 5 degrees, upon muscle adenine nucleotide loss and lactate accumulation was studied in six Thoroughbred horses. Minimal change occurred in the adenosine triphosphate (ATP) content of the middle gluteal muscle at speeds of 10 m.s-1 or less, but significant loss (up to 47%) had occurred in all horses by 12 m.s-1. The decline in ATP significantly correlated with the accumulation of muscle lactate, beginning shortly after the accumulation of 40 mmol.kg-1 dry muscle lactate. Decline in muscle ATP was mirrored closely b...
Mikami T, Kashiwagi M, Tsuchihashi K, Daino T, Akino T, Gasa S.Equine brain gangliosides were isolated and their structures were characterized, to examine whether equine brain has N-glycolyl neuraminic acid in gangliosides, since other mammals predominantly possess N-acetyl neuraminic acid in brain gangliosides, and equine erythrocytes and organs except the brain have gangliosides exclusively containing N-glycolyl neuraminic acid. The gangliosides purified from the brain were identified by proton NMR spectroscopy and mass spectrometry, as well as GLC, resulting in their identification as GM4, GM3, GM2, GM1, GD1a, GD1b, and GT1b. Of these gangliosides, GM3...
