Changes in circulatory antioxidant status in horses during prolonged exercise.

Prolonged low-medium intensity exercise is associated with increased oxidative stress in humans. We hypothesized that competitive equine endurance racing would induce changes in circulatory antioxidants and produce systemic oxidative stress. Forty horses competing in a 140-km endurance race in warm conditions [shade temperature 15-19 degrees C; 62-88% relative humidity (%RH)] were sampled before (Pre), immediately after exercise (End) and at approximately 16 h into recovery (+16 h). Plasma ascorbic acid concentration was not different between Pre [11.1 (median); 4.6-20.3 micromol/L (range)] and End [9.7; 3.0-38.9 (range) micromol/L] but was significantly decreased at +16 h (5.5; 2.8-15.5 micromol/L; P < 0.05). Total red cell hemolysate glutathione (TGSH) concentration was significantly reduced by exercise (Pre 1261; 883-1532 micromol/L; End 1065; 757-1334 micromol/L; P < 0.05) and at +16 h recovery (1032; 752-1362 micromol/L; P < 0.05). Glutathione redox ratio was unchanged by exercise but was significantly decreased at +16 h compared with that at both Pre and End (P < 0.05). The concentration of total barbituric acid reactive substances (TBARS) in plasma was increased compared with that at Pre (309; 66-1048 nmol/L), both at End (408; 170-1196 nmol/L; P < 0.05) and +16 h (380; 99-1161 nmol/L; P < 0.05). alpha-Tocopherol was unchanged by exercise or recovery. Mean race speed was 16.5 +/- 1.6 km/h and ranged from 13.9 to 19.7 km/h. Mean speed during competition in horses that completed the full 140 km (n = 28) was significantly correlated with end of exercise ascorbic acid (r = 0.622; P = 0.0004). Although there were increases in creatine phosphokinase (CK), aspartate aminotransferase (AST) and TBARS and a loss of TGSH, this study failed to demonstrate evidence of classical oxidative stress.

[1]  D. Marlin,et al.  Effect of chronic airway inflammation and exercise on pulmonary and systemic antioxidant status of healthy and heaves-affected horses. , 2010, Equine veterinary journal.

[2]  D. Sklan,et al.  Antioxidant status of horses during two 80-km endurance races. , 2002, The Journal of nutrition.

[3]  K. Fallon.  The Acute Phase Response and Exercise: The Ultramarathon as Prototype Exercise , 2001, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[4]  K. Hinchcliff,et al.  Effect of dietary supplements containing antioxidants on attenuation of muscle damage in exercising sled dogs. , 2000, American journal of veterinary research.

[5]  R. Stupnicki,et al.  Iron status in female endurance athletes and in non-athletes. , 2000, International journal of sport nutrition and exercise metabolism.

[6]  Y. Yamazaki,et al.  Vitamin E supplementation attenuates leakage of enzymes following 6 successive days of running training. , 2000, International journal of sports medicine.

[7]  S. Powers,et al.  Analysis of cellular responses to free radicals: focus on exercise and skeletal muscle , 1999, Proceedings of the Nutrition Society.

[8]  T. Art,et al.  Indices of oxidative stress in blood and pulmonary epithelium lining fluid in horses suffering from recurrent airway obstruction. , 1999, Equine veterinary journal.

[9]  M. Taskinen,et al.  A marathon run increases the susceptibility of LDL to oxidation in vitro and modifies plasma antioxidants. , 1999, American journal of physiology. Endocrinology and metabolism.

[10]  E. Chiaradia,et al.  Effect of exercise training, selenium and vitamin E on some free radical scavengers in horses (Equus caballus). , 1999, Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology.

[11]  T. Dutkiewicz,et al.  The influence of exogenous antioxidants and physical exercise on some parameters associated with production and removal of free radicals. , 1999, Die Pharmazie.

[12]  C. Anuradha,et al.  Exercise, depletion of antioxidants and antioxidant manipulation , 1998, Cell biochemistry and function.

[13]  A. Donnelly,et al.  Elevated serum antioxidant capacity and plasma malondialdehyde concentration in response to a simulated half-marathon run. , 1998, Medicine and science in sports and exercise.

[14]  J. Salonen,et al.  Effect of combined coenzyme Q10 and d-alpha-tocopheryl acetate supplementation on exercise-induced lipid peroxidation and muscular damage: a placebo-controlled double-blind study in marathon runners. , 1998, Free radical research.

[15]  L. Lawrence,et al.  Effect of dietary vitamin E supplementation on the integrity of skeletal muscle in exercised horses. , 1997, Journal of animal science.

[16]  T. Vasankari,et al.  Increased serum and low-density-lipoprotein antioxidant potential after antioxidant supplementation in endurance athletes. , 1997, The American journal of clinical nutrition.

[17]  D. Marlin,et al.  Plasma iron in elite horses at rest and after transport , 1996, Veterinary Record.

[18]  P. Mills,et al.  Simultaneous quantitation of oxidised and reduced glutathione in equine biological fluids by reversed-phase high-performance liquid chromatography using electrochemical detection. , 1995, Journal of chromatography. B, Biomedical applications.

[19]  C. Sen.  Oxidants and antioxidants in exercise. , 1995, Journal of applied physiology.

[20]  M. Kanter.  Free radicals, exercise and antioxidant supplementation. , 1994, The Proceedings of the Nutrition Society.

[21]  J. Pepper,et al.  Transient iron-overload with bleomycin-detectable iron present during cardiopulmonary bypass surgery. , 1994, Free radical research.

[22]  J. Keul,et al.  Lipid peroxidation and antioxidative vitamins under extreme endurance stress. , 1994, Acta physiologica Scandinavica.

[23]  H. Hintz,et al.  Effect of vitamin E status on lipid peroxidation in exercised horses. , 1992, Equine veterinary journal.

[24]  J. Sastre,et al.  Exhaustive physical exercise causes oxidation of glutathione status in blood: prevention by antioxidant administration. , 1992, The American journal of physiology.

[25]  F. Kelly,et al.  Time course of vitamin E repletion in the premature infant , 1990, British Journal of Nutrition.

[26]  D. Snow,et al.  Oral administration of ascorbic acid to horses. , 1987, Equine veterinary journal.

[27]  P. Hornsby,et al.  The role of lipid peroxidation and biological antioxidants in the function of the adrenal cortex. Part 1: A background review , 1983, Molecular and Cellular Endocrinology.

[28]  D. Sampson,et al.  Changes in plasma biochemistry in horses competing in a 160 km endurance ride. , 1983, Australian veterinary journal.

[29]  M. Nimmo,et al.  Alterations in blood, sweat, urine and muscle composition during prolonged exercise in the horse , 1982, Veterinary Record.

[30]  D. Marlin,et al.  Muscle ATP loss and lactate accumulation at different work intensities in the exercising Thoroughbred horse , 2004, European Journal of Applied Physiology and Occupational Physiology.

[31]  D. Marlin,et al.  Effects of exercise intensity and environmental stress on indices of oxidative stress and iron homeostasis during exercise in the horse , 2004, European Journal of Applied Physiology and Occupational Physiology.

[32]  C. Behn,et al.  Role of exercise and ascorbate on plasma antioxidant capacity in thoroughbred race horses. , 2001, Comparative biochemistry and physiology. Part A, Molecular & integrative physiology.

[33]  C. Sen,et al.  Antioxidants and physical exercise , 2000 .

[34]  L. Niskanen,et al.  Blood glutathione homeostasis as a determinant of resting and exercise-induced oxidative stress in young men. , 1999, Redox report : communications in free radical research.

[35]  J. Ordóñez‐Llanos,et al.  Ascorbic acid inhibits the increase in low‐density lipoprotein (LDL) susceptibility to oxidation and the proportion of electronegative LDL induced by intense aerobic exercise , 1998, Coronary artery disease.

[36]  M. Lamy,et al.  Blood levels of reduced/oxidized glutathione and plasma concentration of ascorbic acid during eccentric and concentric exercises of similar energy cost. , 1994, Archives internationales de physiologie, de biochimie et de biophysique.