Enzymes are biological catalysts that facilitate biochemical reactions in horses by lowering the activation energy required for these processes. They are involved in various physiological functions, including digestion, metabolism, and cellular repair. Common enzymes in equine biology include amylase, lipase, and lactate dehydrogenase, each playing a specific role in the breakdown of nutrients and energy production. The activity and concentration of these enzymes can vary in response to different physiological and pathological conditions, serving as potential indicators in veterinary diagnostics. This page compiles peer-reviewed research studies and scholarly articles that explore the function, regulation, and clinical implications of enzymes in equine health.
Holland RA.Using a double beam stopped-flow apparatus, measurements were made of the velocity constant of the reaction CO + Hb --> COHb in solution and in the red cells of human beings, rabbits, horses, and goats. The solution constant (l') at 37 degrees C for human beings was 362 mM(-1) sec.(-1); in other species l' was somewhat lower. Two rabbits, despite having apparently identical hemoglobins had significantly different values for l'. The energy of activation (E) of l' was between 8 and 11 kcal/mole in all cases. The cell reaction constant (l'(c)) at 37 degrees was between 61 and 73 mM(-1) sec.(-1...
Black JA, Leaf G.1. The effects of cyanogen bromide on horse-heart cytochrome c and horse-heart myoglobin have been investigated. Cytochrome c yielded four fragments, of which two were haemopeptides. The two colourless peptides had amino acid compositions corresponding to those that are expected, on the basis of the sequence proposed for horse-heart cytochrome c by Margoliash, Smith, Kreil & Tuppy (1961), from cleavage at both methionine residues. Of the two haemopeptides, one was isolated and shown to be that derived from cleavage at only one methionine residue, that nearer to the C-terminus of the peptid...
Science (New York, N.Y.)June 18, 1965
Volume 148, Issue 3677 1603-1604 doi: 10.1126/science.148.3677.1603
TRUJILLO JM, WALDEN B, O'NEIL P, ANSTALL HB.Distinctly different electrophoretic patterns of red cell glucose-6-phosphate dehydrogenase were resolved from the hemolyzates of horse and donkey erythrocytes. Examination of their reciprocal hybrids, mules and hinnies, showed that the red cells of female mules and female hinnies contain both horse and donkey G-6-PD; the male mule with an X chromosome from its horse mother contained pure horse G-6-PD, whereas the male hinny with the donkey X chromosome contained pure donkey G-6-PD. These findings on the male reciprocal hybrids suggest X-linkage.
KAMINSKI M, GAJOS E.TWENTY-THREE fresh and 28 frozen (1–11 years old) samples of horse sera, 62 frozen donkey sera (3–11 years old), 24 frozen mule sera (2–10 years old), and 1 frozen 2-year-old serum sample of a hinny (offspring of a she-ass by a stallion) were studied by starch- and agar-gel electrophoresis (starch gel: horizontal migration, discontinued buffer system; tris-citrate pH 8.7 and borate 0.3 M, pH 8.2; 2 V/cm for 14 h; 10 samples analysed simultaneously; 0.1 ml. serum mixed with soluble starch Merck; agar gel: 0.8 per cent agar in veronal buffer 0.025 M, pH 8.2; 4.5 V/cm; 2½ h; 10 samples on ...
Svistunenko DA, Dunne J, Fryer M, Nicholls P, Reeder BJ, Wilson MT, Bigotti MG, Cutruzzolà F, Cooper CE.The reactions of hydrogen peroxide with human methemoglobin, sperm whale metmyoglobin, and horse heart metmyoglobin were studied by electron paramagnetic resonance (EPR) spectroscopy at 10 K and room temperature. The singlet EPR signal, one of the three signals seen in these systems at 10 K, is characterized by a poorly resolved, but still detectable, hyperfine structure that can be used to assign it to a tyrosyl radical. The singlet is detectable as a quintet at room temperature in methemoglobin with identical spectral features to those of the well characterized tyrosyl radical in photosystem...
McGorum BC, Murphy D, Love S, Milne EM.The clinicopathological features of 50 cases of equine hepatic disease were reviewed. There was a wide range of clinical signs and at least 50 per cent of the animals exhibited either dull demeanour, anorexia, abdominal pain, cerebral dysfunction and/or weight loss. Life-threatening complications of hepatic failure recorded were: gastric impaction in 10 cases, bilateral laryngeal paralysis in seven cases and coagulopathy in five cases. All the cases had high activities of gamma-glutamyl transferase (GGT) and most had high activities of glutamate dehydrogenase (GLDH) and high concentrations of ...
Flisińska-Bojanowska A, Komosa M, Gill J.1. The diurnal changes in the glucose level and in activity of FDPA, A1AT and AspAT in four pregnant standard-bred mares were studied. 2. As a control four barren mares, were kept and examined in the same conditions. 3. Blood samples were taken every 4 hr for one day, each month, throughout pregnancy, or one year. 4. A diurnal rhythm in activity of A1AT and AspAT in barren mares was found. The pregnancy masked diurnal rhythm in activities of both transaminases. 5. No diurnal rhythm in glucose level and FDPA activity in both groups of mares was observed. 6. Seasonal cyclicity was found in all i...
Nic An Ultaigh S, Ryan MF.Proteinases released during the in vitro maintenance of asynchronous cultures of the free-living nematode Caenorhabditis elegans were characterized on the basis of subunit composition, fluorogenic substrate specificity, inhibitor sensitivity and pH optima. Cysteine proteinases are present in the excretory-secretory products (ESP) as indicated by the hydrolysis of cathepsin fluorogenic substrates and confirmed by immunoblotting. Serine proteinases were predominant as indicated by substrate gel analysis and inhibitor studies. The presence of metallo-proteinases was also indicated by inhibitor st...
Ayo JO, Ake AS, Abimbola AA.The study aimed to evaluate effects of packing (load-carrying) and trekking on hematological and biochemical parameters in donkeys during the hot-dry season. Ten pack donkeys, aged 2-3 years, weighing 93 ± 2.7 kg were enrolled in the study and randomly divided into two groups of five animals each. Group 1 donkeys were subjected to packing + trekking while group 2 trekked only. All the donkeys trekked 20 km thrice, 1-day apart. Blood was collected before and after packing or trekking for hematological evaluation; and serum analyzed for electrolyte concentrations, and aspartate aminotransfera...
Walters B, Trumble TN, Wendt-Hornickle E, Kennedy M, Guedes A.Apoptosis is an important mechanism underlying chondrocyte loss in osteoarthritis that could be affected by modulation of lipid signaling via inhibition of cyclooxygenases (COX) and soluble epoxide hydrolase (sEH). Objective: To determine the impact of inhibiting COX and sEH alone or in combination on apoptosis of equine chondrocytes. Methods: Cultured primary equine chondrocytes were subjected to serum deprivation or incubation with 1 μg/ml tunicamycin for 24 h to induce apoptosis via caspase activation and endoplasmic reticulum (ER) stress, respectively. Cells were treated with the non-se...
HORI J, AOKI K.Electrophoretic studies were made of normal horse and human serum albumins over the pH range 3.6–6.8 and at 25 °. The ionic strength of acetate or phosphate buffer used was 0.1, and the concentration of protein was 0.5% (g./100 ml.). Patterns were usually enantiographic and there were two (N and F1) or three (N, F1, and F2) boundaries in the pH range 3.6–5.2. The areas of the N and F1 boundaries changed continuously with pH, and the area of F2 was almost constant. The results were interpreted, in the same way as was previously done in the case of bovine serum albumin, by the isomerization...
Giacominelli-Stuffler R, Frangipane di Regalbono A, Traversa D, Geurden T, Marcer F, Di Francesco A, Angelini C, di Cesare A, Storelli MM....Leukotrienes are products of the arachidonic acid metabolism and act as potent inflammatory mediators modulating the immune response and various physiological processes. This study evaluated the expression and activity of 5-lipoxygenase (5-LOX), the enzyme that catalyzes the first two steps in the biosynthesis of leukotrienes, in horses infected by larval cyathostomins. Tissue samples from dorsal and ventral colon, and from the cecum were collected from 16 horses slaughtered for human consumption. Samples were analyzed to estimate the burdens of encysted cyathostomin larvae and adult luminal s...
Retamal CA, Dias AJ, Brasil FC, Lanzana FR, López ML.The expression of α-D-mannosidase activity was fluorometrically and electrophoretically assessed in spermatozoa, epididymal fluid and homogenates of stallion epididymal tissue. Enzyme activity had regional differences; it was higher (P<0.05) in samples from the cauda epididymal region than in samples from the proximal caput region (largely composed of efferent ducts). Based on enzyme activity, as a function of pH of the assay substrate, electrophoretic analysis in native and native/SDS-PAGE conditions, and the effect of inhibitors or activators, we inferred the presence of at least two cat...
Berti A, Tremori E, Pazzagli L, Degl'Innocenti D, Camici G, Cappugi G, Manao G, Ramponi G.Acylphosphatase was purified from rat skeletal muscle essentially by gel filtration and high-performance ion-exchange chromatography. The complete amino acid sequence was reconstructed by using the sequence data obtained from tryptic, peptic, and S. aureus V8 protease peptides. The protein consists of 96 amino acid residues and is acetylated at the NH2-terminus. The immunological cross-reactivity of acylphosphatase from rat and horse skeletal muscle was examined by ELISA. The reaction with rabbit antiserum revealed the presence of at least five antigenic sites on rat enzyme, two of which are c...
JENNINGS FW, MULLIGAN W.THE chemical analyses reported in this paper arc the result of an investigation on the sera of thirty normal horses from a heavy draught horse stable in Glasgow. Determinations have been made of scrum proteins (albumin and total globulin), alkaline phosphatase, bilirubin, calcium, magnesium, inorganic phosphate and urea. Estimations of some of these constituents have already been carried out by a number of workers, but in the majority of cases the investigation has been confined to one or two constituents relevant to the problem being studied, and many of the data available are a by-product of...
Oh R, Tamaoki BI.The microsomal fraction (10 000–105 000 × g precipitate) of equine testes was fractionated into the smooth- and the rough-surfaced microsomal subfractions by a sucrose density-gradient centrifugation in the presence of CsCl. The validity of this fractionating procedure was confirmed by electron microscopic examination and also by chemical analysis of the RNA contents in these subfractions. The aromatizing enzyme system (19-hydroxylase and aromatase) which was concentrated in the microsomal fractions among the organellae was found to be localized in the smoothsurfaced microsomal fraction. Th...
Jiménez PA, García L, Adarmes H, González E, Valenzuela MA.ATPase and ADPase activities capable of hydrolyzing nucleoside di- and triphosphates in the presence of Ca2+ are present in synovial membrane of metacarpophalangeal joint mainly associated to membrane fractions. These hydrolytic activities have been considered involved in the inflammatory process where ATP and ADP are inflammatory mediators while adenosine counteracts this effect. Both, subcellular localization and kinetic properties of these nucleotidase activities, suggest that could correspond to single enzyme called ATP-diphosphohydrolase or apyrase. The comparison of the activity on ATP-C...
Blakley BR, Skelley KW.Normal cholinesterase activity in brain tissue was measured in various mammalian and avain species. The cholinesterase activity in the cerebrum of cattle, swine, sheep and horses was approximately 2-3 umoles/min/g of tissue in each instance. The whole brain cholinesterase activity of small feral mammals was approximately 2 to 5 fold greater than the domestic animals. Considerable interspecies variability was present in the feral mammals. Similar variability was also observed in the avian brain cholinesterase determinations. The avian whole brain cholinesterase activities ranged from 9.78 to 21...
Thomas DA, Furman PA.The reverse transcriptase of Equine Infectious Anemia Virus (EIAV) was partially purified from virus particles and appeared to be a heterodimer with subunit molecular masses of 70 kdal and 59 kdal. The polymerase activity of this enzyme had an absolute requirement for a divalent cation, preferring Mg++ over Mn++. Addition of a monovalent cation to the reaction mixture enhanced, but was not required for enzyme activity. Kinetically, the reverse transcriptase of EIAV is similar to the reverse transcriptase of Human Imunodeficiency Virus Type 1 (HIV-1). Both enzymes have similar Km values for 2'-...
van de Lest CH, van den Hoogen BM, van Weeren PR, Brouwers JF, van Golde LM, Barneveld A.Osteochondrosis (OC) is a disturbance in the process of endochondral ossification, a process in which cartilage is mineralised and transformed into bone. In this process different biochemical events occur, of which the cartilage component has been studied so far almost exclusively. In this study we concentrated on the biochemical characterisation of normal and osteochondrotic subchondral bone, by analysis of enzyme activities, DNA content and phospholipids (PL). In subchondral bone, lysyl oxidase and both total and bone alkaline phosphatase activity were significantly increased in all degrees ...
Bourebaba N, Sikora M, Qasem B, Bourebaba L, Marycz K.Equine metabolic syndrome (EMS), which encompasses insulin resistance, low-grade inflammation and predisposition to laminitis is a critical endocrine disorder among the most prevalent conditions affecting horses from different breeds. According to the most recent research, low human sex hormone-binding globulin (SHBG) serum levels correlate with an increased risk of obesity, insulin resistance and diabetes, and may contribute to overall metabolic dysregulations. This study aimed to test whether exogenous SHBG could protect EMS affected adipose-derived stromal stem cells (EqASC) from apoptosis,...
Farooq A, Lee M, Han S, Jung GY, Kim SJ, Jung MY.Brachybacterium species have been identified in various ecological niches and belong to the family within the phylum . In this study, we isolated a novel JHP9 strain from horse feces and compared its kinetic, biochemical, and genomic features with those of other strains. Moreover, comparative genomic analysis using publicly available genomes was performed to determine the properties involved in their ecological adaptation and metabolic potential. Novel species delineation was determined phylogenetically through 16S rRNA gene similarity (up to 97.9%), average nucleotide identity (79.5-82.5%...
Potier JFN, Durham AE, Modi R, Rosenberg W, Dash SA.Liver disease is common in equine practice, and treatment and prognosis are dependent on histopathologic examination of biopsies. Liver biopsy is invasive and expensive which restricts its use. Serum markers are used to predict hepatic fibrosis in humans. This study aimed to investigate the enhanced liver fibrosis (ELF) test, based on serum Hyaluronic Acid (HA), procollagen III N-terminal peptide (PIIINP), and tissue inhibitor of metalloproteinase 1 (TIMP-1) to detect hepatic fibrosis in equids. Four groups were included; two with increased serum concentrations of liver-derived enzymes and a l...
Sun W, Yin Q, Wan H, Gao R, Xiong C, Xie C, Meng X, Mi Y, Wang X, Wang C, Chen W, Xie Z, Xue Z, Yao H, Sun P, Xie X, Hu Z, Nelson DR, Xu Z, Sun X....Horse chestnut (Aesculus chinensis) is an important medicinal tree that contains various bioactive compounds, such as aescin, barrigenol-type triterpenoid saponins (BAT), and aesculin, a glycosylated coumarin. Herein, we report a 470.02 Mb genome assembly and characterize an Aesculus-specific whole-genome duplication event, which leads to the formation and duplication of two triterpenoid biosynthesis-related gene clusters (BGCs). We also show that AcOCS6, AcCYP716A278, AcCYP716A275, and AcCSL1 genes within these two BGCs along with a seed-specific expressed AcBAHD6 are responsible for the fo...
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.Horses competing in cross-country tests are subjected to high physical demands. Within the scope of this prospective longitudinal study, blood values of 20 elite eventing horses were examined before and after two- to four-star cross-country rides. The aim was to find out whether blood-based markers for skeletal muscle and cardiac muscle function change after cross-country exercise. Parameters that provide information about fluid balance, muscle enzymes, metabolites and cardiac muscle-specific markers were investigated. We developed an approach to eliminate the concentration changes caused by r...
Egyptien S, Deleuze S, Ledeck J, Ponthier J.Stallion sperm analysis is indicated for infertility diagnosis, pre-sale expertise, production of fresh or frozen doses, and frozen straw quality control. Various collection methods are described, and numerous assays can be performed on semen. Determining an approach for each of these cases is challenging. This review aims to discuss how to obtain relevant clinical results, answering stallion owners' concerns. Semen can be collected with an artificial vagina on a phantom or a mare, by electro-ejaculation under anesthesia, or after pharmacological induction. The collection method influences the...
Miranda ALS, Antunes BC, Minozzo JC, Lima SA, Botelho AFM, Campos MTG, Chávez-Olórtegui C, Soto-Blanco B.Antivenom production against venom relies on horses being immunized and bled for plasma harvest. One horse can partake in several cycles of antivenom production, which will require years of constant venom and adjuvant inoculation and bleeding. The actual impact on the health of horses that participate in several antivenom-producing cycles is unknown. Therefore, this study aimed to evaluate the general health status of horses that underwent at least six cycles of loxoscelic antivenom production. Seven crossbred horses that had partaken in six to eight complete antivenom-producing cycles were u...
Scantamburlo G, Nofziger C, Paulmichl M, Vanoni S.Because of their importance as companion animals or as racehorses, horses can be treated with various drugs. Although it is known that drug withdrawal times can vary for each horse, pharmacogenetics for these animals has not been adequately studied and requires further development. Since is responsible for the metabolism of 25-30% of drugs in humans, including some used to treat horses, a study of the family in horses was conducted to define its genetic structure as well as its expression pattern in the liver. Unassigned: Genomic DNA extracted from venous blood and mRNA from fresh liver tiss...
Bourebaba L, Kępska M, Qasem B, Zyzak M, Łyczko J, Klemens M, Mularczyk M, Marycz K.Equine metabolic syndrome (EMS) is a steadily growing endocrine disorder representing a real challenge in veterinary practice. As a multifactorial condition, EMS is characterized by three main metabolic abnormalities including insulin resistance, increased adiposity or obesity and hoof laminitis. Adipose tissue dysfunction is recognized as a core pathophysiological determinant of EMS, as it strongly participates to lipotoxicity and systemic metaflammation, both of which have been closely linked to the development of generalized insulin resistance. Besides, sex hormone binding globulin (SHBG) i...
da Rosa G, de Freitas Daudt G, Roman IJ, Cargnelutti JF, Sangioni LA, Flores MM, Vogel FSF.Horses are intermediate hosts of Sarcocystis spp. capable of forming cysts in their musculature. This study aimed to detect sarcocysts and investigate the presence of nucleic acids from Sarcocystis spp. in samples of striated muscles from horses in the State of Rio Grande do Sul, Brazil, necropsied at the Veterinary Pathology Laboratory of the Federal University of Santa Maria. A total of 108 samples were collected from 24 horses and examined through direct examination. Microscopic tissue cysts were observed in three samples: tongue (2) and esophagus (1) from two animals. Extractions were perf...
Ortved KF, Alward L, Cowles B, Linardi R, Barot D, Usimaki A, Fedie JR, Amodie D, Goodrich LR.Alpha 2 macroglobulin (A2M), a multi-functional protein in the plasma protease inhibitor class, regulates proinflammatory cytokines and the clearance of chondrodestructive enzymes in cases of joint injury and osteoarthritis (OA). The purpose of this study was to compare A2M concentrations in equine plasma samples processed by three commercial devices developed for stall-side regenerative joint therapy. Unassigned: Plasma samples were obtained from healthy adult horses ( = 13). Mass spectrometry analysis was used to determine the concentration of protein analytes in each sample. Selected re...
Ding J, Gu B, Meng J, Hu M, Wang W, Liu J.Traditional Chinese medicine (TCM) is widely used in humans and animals, which is very important for health. TCM affects the body 's immunity and changes in intestinal flora. This study was conducted to investigate the effects of dietary Hong-bailanshen (HBLS) supplementation in horses on serum biochemical profile, antioxidant enzymes and gut microbiota. Unassigned: In this study, five horses were selected. On day 0, 14, 28, blood samples and feces were collected on days 0, 14, and 28 to analyse gut microbiota, serum biochemical and redox indexes. Unassigned: The results showed that the additi...
Bujok J, Pavľak A, Walski T, Zigo F, Trochanowska-Pauk N, Bohara R, Miśta D.Combat training of police horses, involving physical activity in the presence of environmental stressors, poses a risk of oxidative stress. This study compared the oxidative imbalance after combat training in horses in the regular police service and in horses that had just been schooled. Blood collection was performed immediately after training and after 16 h rest. The activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant status (TAS) were determined as the markers of enzymatic antioxidant defence. At the same time, lipid peroxidation (TBAR...
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.After submaximal exercise, blood values of eventing horses show physiological reactions. This prospective longitudinal study investigated blood parameters in 20 elite eventing horses before and after two-four-star cross-country rides. Using a mixed model adjusting for plasma volume shift, we assessed exercise-dependent parameters and compared blood values with reference ranges for healthy horses at rest. Following exercise, cortisol, triiodothyronine (T3) and thyroxine (T4) showed short-term increases, and superoxide-dismutase showed a small short-term increase. Hepatic values showed short-ter...
