Biochemical and Antioxidant Changes in Plasma and Erythrocytes of Pentathlon Horses Before and After Exercise

Abstract

Physical exercise in the horse induces a series of normal physiological and biochemical adaptations. Increasing metabolism and oxygen uptake may induce oxidative stress in various organs. The aim of this study was to examine exercise-induced changes in some plasma and RBC biochemical and antioxidant variables in pentathlon horses. Blood samples were taken from 14 horses before, immediately after, and 24 hours after competing in two 1-minute runs of intense exercise over jumps. The peak intensity periods were preceded by a 20-minute warm-up and separated by a 20-minute break. The following plasma biochemical analytes were determined: total protein, uric acid, and lactate concentrations, and lactate dehydrogenase (LDH) and creatine kinase (CK) activities. Total antioxidant status (TAS) and the ferric reducing ability of plasma (FRAP) also were measured. Thiobarbituric acid-reactive substances (TBARS), reduced glutathione (GSH), and total protein concentrations, and glutathione peroxidase (GSHPx) and superoxide dismutase (SOD) activities were determined in RBC hemolysates. Significantly increased concentrations of total protein, lactate, and FRAP, and increased activities of CK and LDH were observed immediately postexercise compared with pre-exercise samples (P<0.05). All results returned to approximately initial values after 24 hours of rest. RBC GSH and TBARS concentrations did not change immediately after exercise, but decreased after 24 hours of rest (P<0.05). Plasma uric acid and FRAP values were positively correlated in a linear model (r = 0.78). In summary, the type of exercise applied in this study, which can be considered quite usual for pentathlon horses, caused detectable biochemical and lipid peroxidative changes in plasma and RBCs. FRAP and TAS values changed in opposite directions, indicating that when antioxidant capacity is assessed using different methods, highly different results may be obtained.

Biochemical responses to a non-standard exercise in horses trained for jumping

“…Williams et al (2004) found that GSHPx activity in mU/mg of TP was significantly increased (P < 0.05) but no change was found in the concentration of α-tocopherol, which was adjusted to albumin due to changes in body fluid redistribution during endurance exercise. Similarly to our findings, when expressed as units per g of TP, Balogh et al (2001) found unchanged activity of GSHPx and SOD (both in U/g of TP), and unaffected index of lipid peroxidation (in mmol/g of TP) in pentathlon competition finishing horses, but the index of lipid peroxidation was decreased after 24 h of rest.…”

Cytogenetic and oxidative alterations after exposure of cultured human whole blood cells to lithium metaborate dehydrate

“…And the capacity in plasma is related to production or intake of antioxidants. Hence, it monitors the action potential to increased or normal status of reactive oxygen species (Miller et al 1993;Lantos et al 1997;Ghiselli et al 2000;Balogh et al 2001). This study reported that LMD treatments at low concentrations (5, 10, 20 and 40 lg/ml) caused significant increase of TAC levels, while TOS levels were not affected.…”

Exercise-induced Modifications on Haematochemical and Electrophoretic Parameters During 1600 and 2000 Meters Trot Races in Standardbred Horses

“…It is well known that activities of various enzymes, particularly of creatine kinase and glutamate pyruvate transaminases, increase following muscle damage o r strenuous muscular exercise (Balogh et al, 2001).…”