Topic:Antioxidants
Antioxidants in horses refer to a group of molecules that help protect cells from oxidative stress caused by reactive oxygen species (ROS). These compounds can be naturally occurring within the horse's body or obtained through diet. Antioxidants play a role in maintaining cellular integrity and supporting overall health by neutralizing free radicals. Common antioxidants relevant to equine health include vitamin E, vitamin C, and glutathione. Their presence and activity in the body are influenced by factors such as diet, exercise, and environmental conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the sources, mechanisms, and potential impacts of antioxidants on equine physiology and well-being.
[Histochemical and biochemical changes in skeletal muscles of rhabdomyolysis-sensitive racehorses following exertion. III: Elevated activity of various antioxidant enzymes]. In this communication, the results of a histochemical and biochemical enzyme study on gluteus medius muscle of horses, sensitive to exertional myopathy, during attacks of rhabdomyolysis are presented. For the biochemical study the biopsy specimens investigated were selected by means of histological and enzyme histochemical staining methods. Dissected specimens were used which contained groups of muscle fibres with a high or low activity of glucose-6-phosphate dehydrogenase. The activity of glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, glutathione reductase, glutathione per...
[Evaluation of the effects of lipids isolated from sublimated mare’s milk on the indicators of lipid metabolism and fatty acid composition of blood plasma, erythrocyte stroma and liver tissue in rats]. During six weeks rats were given a ration containing, as the only source of fat, lipids of sublimated mare's milk that had been stored with or without antioxidants (quercitrol, bisalcophen) during 3 months. The influence of specific quality of the ration fat on lipids and fatty acid composition of lipids in blood plasma, erythrocytic stroma and liver tissue, as well as on lipid peroxidation in the tissues was studied in the test animals. No changes induced by the lipids from sublimated mare's milk were detected in the parameters studied.
The influence of dietary selenium levels on blood levels of selenium and glutathione peroxidase activity in the horse. Twenty mature geldings, averaging 535 kg, were used to determine the influence of dietary selenium (Se) on the blood levels of Se and Se-dependent glutathione peroxidase (SeGSH-Px) activity in the horse. Horses were randomly assigned within breed to four treatments consisting of five horses each and fed a basal diet containing .06 ppm of naturally occurring Se. Diets were supplemented with .05, .10 and .20 ppm Se, as sodium selenite. Blood was drawn for 2 wk before, and for 12 wk following, the inclusion of supplement Se in the diets. Whole blood and plasma Se concentrations and plasma SeGSH-P...
Glutathione peroxidase activity in the blood of healthy horses given different selenium supplementation. Glutathione peroxidase (GSH-px) activity in the blood is correlated to the amount of selenium which was given to the horse. Currently recommended doses of selenium seem to be sufficient in order to prevent selenium deficiency. The blood GSH-px in foals reflects the amount of selenium given to the mare during pregnancy.
Selenium and vitamin E in horses. A survey of selenium and vitamin E concentrations in horses was conducted at four breeding farms in New York. There were no significant changes in mean blood selenium concentrations in horses at the three sampling dates whereas vitamin E concentrations underwent seasonal fluctuations. The mean blood selenium concentration in this survey for horses fed local feed was 7.7 microgram/dl. Horses fed commercial feed had a mean blood selenium concentration of 15.6 microgram/dl. A 0.94 correlation coefficient was found between blood glutatione peroxidase activity and blood selenium concentrations in h...
The effect of binding ions on the oxidation of horse heart ferrocytochrome c. The research explores how different binding ions affect the oxidation speed of horse heart ferrocytochrome c, a protein, by potassium ferricyanide at a constant ionic strength. Studying the Ion Effect […]
Blood glutathione peroxidase activity in horses in relation to muscular dystrophy and selenium nutrition. The activity of glutathione peroxidase, a selenium containing enzyme, was measured in the blood of horses to determine its usefulness as an indicator of selenium status. In 15 horses the enzyme activity was positively related to the blood selenium concentration (P less than .001, r-0.98) over the range of enzyme activities of 8.2 to 140 units (mumoles NADP-oxidised/min/gHb) and selenium concentrations of 0.24 to 2.74 mumol/l. In a group of 8 horses which 2 foals had died with lesions of muscular dystrophy the enzyme activity increased from a mean of 11.8 units before treatment with selenium to...
Autoxidation in milk rich in linoleic acid. II. Modification of the initiation system and control of oxidation. Factors contributing to the initiation of lipid oxidation in cow's and mare's milk containing high levels of polyunsaturated fatty acids were studied. Addition of H2O2 just after milking, in slight excess of the stoichiometric amounts required to destroy ascorbic acid, delayed the development of oxidized flavours in cow's milk high in linoleic acid. Hydrogen peroxide treatment followed by the addition of alpha-or gamma-tocopherols prevented lipid oxidation in cow's milk even when 0.1 mg Cu/l milk was added. When used separately in the presence of Cu these treatments were ineffective as was but...
Digitoxin metabolism by rat liver microsomes. It has been found that NADPH-dependent hydroxylation of dimethylaniline, aniline, p- and o-nitroanisol and lipid peroxidation is inhibited by the tyrosine-copper (II) complex (low molecular weight analog of superoxide dismutase), which is indicative of a possibility of superoxide radicals formation in these reactions. The inhibition of the above-mentioned reactions with Tyr2-Cu2+ is less pronounced or absent, if cumole hydroperoxide is used as cosubstrate instead of NADPH. Differences in the Tyr2-Cu2+ complex effects on the cumule hydroperoxide-dependent xenobiotics hydroxylation and lipid per...
The autoxidation of horse hemoglobin: the effect of glutathione. The reduced glutathione in the erythrocyte was found to inhibit the autoxidation of purified horse hemoglobin. It was observed that much higher concentrations of oxidized glutathione also stabilize hemoglobin. The stabilization by oxidized glutathione most likely involves the formation of a mixed disulfide with the reactive β-93 sulfhydryl groups on the hemoglobin. A similar effect is also observed with N-ethyl- maleimide and HgCl2 which also react with the sulfhydryl groups. The apparent stabilization by reduced glutathione is partially due to the reduction of ferrihemoglobin formed by autox...
Stability of reduced ascorbic acid in mares’ milk. Fifteen samples of mares' milk with initial potencies of from 86 mg to 161 mg of reduced ascorbic acid per liter were stored in the dark at 10°C. They were assayed at daily or longer intervals. Four samples observed for 10 days lost an average of 2.5 mg per liter daily; 4 samples stored 20 days lost 1.8 mg per day; 2 stored 28 days lost 1.3 mg daily; and 3 observed for 33 days lost 1.1 mg per liter per day. These data show that the rate of loss of reduced ascorbic acid from mares' milk is only a fraction of the rate of loss from cows' milk.
L-carnitine added to post-thawed semen acts as an antioxidant and a stimulator of equine sperm metabolism. The objective of this study was to enhance the in vitro sperm quality and in vivo fertility of frozen-thawed equine semen by the addition of l-carnitine (LC) to post-thawed semen. Different concentrations of LC were added to thawed samples to obtain four treatments control and 0.5, 1 and 2 mM LC. In the in vitro experiments, sperm motility and kinematics, membrane integrity and intracellular calcium ion concentration ([Ca ] ) were investigated, and the antioxidant bioactivity of LC was assessed by measuring hydrogen peroxide and nitrite concentrations (NO ). The fertility rate was assessed v...