Biochemical and Antioxidant Changes in Plasma, Serum, and Erythrocytes of Horses before and after a Jumping Competition

Identification of mulberry leaf flavonoids and evaluating their protective effects on H2O2-induced oxidative damage in equine skeletal muscle satellite cells

Introduction: 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 H2O2-induced oxidative stress in equine skeletal muscle satellite cells (ESMCs) remains unexplored. Methods: 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 protective effects of these MLFs on H2O2-induced oxidative stress in ESMCs and analyzed the MLF components using metabolomics. Results: The results revealed that pre-treatment with MLFs dose-dependently protected ESMCs against H2O2-induced oxidative stress. The most effective concentrations were 0.8 mg/mL of CEP, 0.6 mg/mL of RP, and 0.6 mg/mL of NB-EP, significantly enhancing EMSC viability (p < 0.05). These optimized MLF concentrations promoted the GSH-Px, SOD and T-AOC activities (p < 0.05), while reducing MDA production (p < 0.05) in H2O2-induced ESMCs. Furthermore, these MLFs enhanced the gene expression, including Nrf2 and its downstream regulatory genes (TrxR1, GPX1, GPX3, SOD1, and SOD2) (p < 0.05). In terms of mitochondrial function, ESMCs pre-treated with MLFs exhibited higher basal respiration, spare respiratory capacity, maximal respiration, ATP-linked respiration compared to H2O2-induced ESMCs (p < 0.05). Additionally, MLFs enhanced cellular basal glycolysis, glycolytic reserve, and maximal glycolytic capacity (p < 0.05). Metabolomics analysis results revealed significant differences in mulberrin, kaempferol 3-O-glucoside [X-Mal], neohesperidin, dihydrokaempferol, and isobavachalcone among the three extraction processes (p < 0.05). Discussion: Our study revealed that MLFs enhance antioxidant enzyme activity, alleviate oxidative damage in ESMCs through the activation of the Nrf2 pathway, and improve mitochondrial respiration and cell energy metabolism. Additionally, we identified five potential antioxidant flavonoid compounds, suggesting their potential incorporation into the equine diet as a strategy to alleviate exercise-induced oxidative stress.

Effects of ozone therapy on hematological, biochemical, and oxidative stress parameters of vaquejada athlete horses

ABSTRACT Ozone therapy is a technique used in several specialties of equine medicine; however, there are few studies on its use in vaquejada (cowboy competition) athlete horses. This study aims to evaluate the potential effect of ozone gas administered by two different routes on hematological and biochemical values and the oxidative stress marker in vaquejada athlete horses. For this, nine healthy equines that followed a training protocol and underwent two treatments were used with an 8-day wash-out between them. The major ozonated autohemotherapy (MOA) treatment group received a volume of 600ml of the O2-O3 mixture at a concentration of 60 µg/mL, and the rectal insufflation (RI) treatment group received 5mL of gas per kg of body weight at a concentration of 15µg/kg performed every 24h on three consecutive days. Results were significant for RBC, hematocrit, and hemoglobin in the hematological variables, and AST and lactate for biochemical and malondialdehyde variables. No statistically significant differences were found in comparisons between treatment groups. Thus, we can conclude that there is no difference between the two therapies, indicating that the two techniques are effective for the application of ozone therapy in horses competing for vaquejada.

Effects of Vitamin E and Coenzyme Q10 Supplementation on Oxidative Stress Parameters in Untrained Leisure Horses Subjected to Acute Moderate Exercise

The effects of antioxidant supplements on exercise-induced oxidative stress have not been investigated in untrained leisure horses. We investigated the effects of 14-day supplementation with vitamin E (1.8 IU/kg/day), coenzyme Q₁₀ (CoQ₁₀; ubiquinone; 800 mg/day), and a combination of both (the same doses as in mono-supplementation) on the blood levels of CoQ₁₀, vitamin E, and oxidative stress parameters in untrained leisure horses subjected to acute moderate exercise. Correlations between lipid peroxidation and muscle enzyme leakage were also determined. Forty client-owned horses were included in the study, with 10 horses in each of the antioxidant and placebo (paraffin oil) groups. Blood parameters were measured before supplementation, before and immediately after exercise, and after 24 h of rest. The differences in individual parameters between blood collection times and groups were analysed with linear mixed models (p ˂ 0.05). None of the supplemented antioxidants affected vitamin E and CoQ₁₀ concentrations, oxidative stress parameters, or serum muscle enzymes. Lipid peroxidation occurred in horses supplemented with placebo and CoQ₁₀ but not in horses supplemented with vitamin E or the combination of both antioxidants. These results suggest that vitamin E alone or in combination with CoQ₁₀ prevented lipid peroxidation in untrained leisure horses subjected to acute moderate exercise.

Daytime Evaluation of Oxidative Stress and Behavioural Parameters of Donkeys (Equus asinus) During The Hot-Dry and Cold-Dry (Harmattan) Season in a Tropical Savannah

The aim of the study was to evaluate oxidative stress and behavioural responses of donkeys during the cold-dry and hot-dry seasons. Thirty donkeys divided into three groups of ten donkeys each according to their age served as experimental subjects. During each season, behavioural and blood parameters of the donkeys were evaluated three times with an interval of one week at 06:00 h, 12:00 h and 18:00 h (GMT+1). During the hot-dry season, the peak dry-bulb temperature (DBT) value of 36.00 ± 1.00°C was recorded at 12:00 h, indicating that the season induced heat stress. The time spent feeding demonstrated diurnal fluctuations in adult, yearling and foal donkeys, with the highest time occurring at 12:00 h in both seasons. The malondialdehyde (MDA) concentrations in adults (2.34 ± 0.14 nMol/L), yearlings (2.28 ± 0.19 nMol/L) and foals (3.48 ± 0.17 nMol/L) during the hot-dry season were significantly (P < 0.05) higher, when compared to the corresponding values (0.96 ± 0.09, 1.18 ± 0.10 and 1.82 ± 0.10 nMol/L, respectively) recorded during the cold-dry season. At 0.3% NaCl-concentration, the percentage haemolysis obtained during the hot-dry season in adult (90.33 ± 0.49%), yearling (91.24 ± 0.88%) and foal (97.44 ± 0.24%) donkeys were significantly (P < 0.05) higher than the corresponding values (78.53 ± 0.98, 78.67 ± 0.58 and 88.23 ± 0.47%, respectively), recorded during the cold-dry season. In conclusion, the hot-dry season induced heat stress in the donkeys, resulting in a decrease in time spent on feeding and oxidative stress, as evidenced by high erythrocyte MDA concentration and percentage haemolysis.

Dataset concerning haematological and biochemical parameters changes in show jumping horses subjected to exercise and plasmapheresis session

This article presents data on the effect of plasmapheresis on clinical, haematological and biochemical parameters in horses following exercise and after a plasmapheresis session. This blood filtration technique was realised on six jumping horses (plasmapheresis group) that underwent three consecutive days of graded physical exercise. The control group (n = 6) went through the same exercise but was not subjected to the plasmapheresis session. Blood was sampled before and after each exercise, also at the beginning and the end of plasmapheresis session. The presented data was obtained by measuring clinical and haemato-biochemical parameters in both groups. The heart and respiratory rates and rectal temperature were recorded. In addition, the number of red blood and white cells, platelets also of lymphocytes, monocytes, eosinophils and granulocytes were counted. Other haematological parameters including, hemoglobin concentration, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration were determined. Concerning the biochemical parameters, the concentrations of albumin, globulin, total protein, glucose, alkaline phosphatase, aspartate aminotransferase, gamma glutamyl transferase, total bilirubin, lactate, creatinine kinase, urea, creatinine, calcium, sodium and potassium were measured. All parameters data were analyzed by a two-way repeated measures analysis of variance followed by Holm-Sidak post-hoc procedure to evaluate the effect of plasmapheresis and time. This paper contains data related to and supporting research articles currently published entitled "Plasmapheresis effect on haematological and biochemical parameters in athletic horses subjected to exercise" (Daden et al., 2019) [1].

Effect of prolonged submaximal exercise on serum oxidative stress biomarkers (d-ROMs, MDA, BAP) and oxidative stress index in endurance horses

Background

Oxidative stress (OS) associated with an intense exercise may have a negative influence on equine health. The aim of this study was to determine the effects of endurance races on oxidative and antioxidative status of horses by evaluating changes in reactive oxygen metabolites (d-ROMs), malondialdehyde (MDA), biological antioxidant potential (BAP) and oxidative stress index (OSI) values. The study was carried out on 53 race starts (28 individual horses) competing at different endurance races according to distance (40 and 80 km) and difficulty (easy and demanding). Blood samples were taken before and after the race.

Results

Compared to levels of OS serum biomarkers before the race, an increase in values of d-ROMs (P <  0.01), MDA (P <  0.01), and BAP (P <  0.001), and a decrease in OSI (P <  0.001) have been noted after the race. Contrary to other measured biomarkers, BAP did not show significant individual effects of horses. Horses competing at shorter races have shown a significant change in d-ROMs (P = 0.002), BAP (P <  0.001) and OSI (P = 0.004), whereas those competing at longer races in MDA (P = 0.002), BAP (P <  0.001) and OSI (P <  0.001) post-race values. Endurance racing induced changes in values of d-ROMs, BAP and OSI during both easy and demanding races.

Conclusions

Changes in all measured OS biomarkers indicate that prolonged aerobic exercise during endurance race could contribute to the imbalance between oxidants and antioxidants in horses, mainly characterised by a pronounced antioxidant response. Biological antioxidant potential was found to be the most reliable biomarker of OS in endurance horses in the present study.

Biochemical response to physical exercise in show-jumping horses

The information on the biochemical response of horses submitted to physical exercise by jumping over obstacles is limited and controversial. The purpose of the present study was to monitor the change in activity of muscle enzymes creatine kinase (CK), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), as well as the serum concentrations of triacylglycerols, cholesterol and creatinine in performance horses. Correlations between study parameters were also estimated. Six healthy Hanoverian geldings were submitted to physical exercise similar to a competition consisting of jumping over barriers over four consecutive days. The applied exercise induced increases of biochemical parameters CK, AST, ALT, triacylglycerols, total cholesterol and creatinine within the reference ranges. The changes in these parameters reflected the changes in skeletal muscle and kidney functions as well as alterations in the type of used energy. Negative correlations were established between CK and ALT at 2 hours, and between triacylglycerols and total cholesterol during the entire period of the study. Also, a positive association was established between СK and AST at 24 hours and between total cholesterol and creatinine before exercise, and at 0 and 2 hours post-exercise. The data from the present study could be utilised as guidelines for prevention and early detection of metabolic disturbances in show jumping horses.

Transport induced inflammatory responses in horses

Deleterious response to road transport is an important problem in equine practice. It determines different physiological, immunological and metabolic changes which lead to increased susceptibility to several disorders such as pneumonia, diarrhea, colics, laminitis, injuries and rhabdomyolisis. The aim of our study was to look for possible relationships between transportation of female young and older horses over a long and short distance and an inflammatory state reflected by an increase of acute phase protein concentration, oxidative stress and muscle injury. The study was conducted on 24 cold-blooded female horses divided into four groups. Six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 550 km, six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 50 km. Plasma and serum were obtained from blood samples taken before transportation (T0), immediately after transportation (T1) and at an abattoir during slaughter (T2). In these samples fibrinogen, MDA, AST and CK were assessed. Fibrinogen increased in all studied groups especially in fillies after long distance transportation, where it reached 205±7.07 mg/dl before transportation, 625±35.35 mg/dl after transportation, and 790±14.14 mg/dl during slaughter. MDA concentrations rose after transportation and reached the maximal level during slaughter. CK activity was more elevated after short transportation in younger horses, whereas initial activity of AST was higher in older horses. We estimated that intensified responses from acute phase, oxidative stress and muscle injury parameters indicated an inflammatory state.

Short- and long-term effect of oral administration of micellized natural vitamin E (D-α-tocopherol) on oxidative status in race horses under intense training

This study tested the effect of micellized vitamin E (D-α-tocopherol; 1,400 IU/d) administered 12 and 1 h orally before training for 1 d (ST-VitE) or 8 d (LT-VitE) compared with an unsupplemented control (CONTROL) on plasma α-tocopherol, thiobarbithuric acid-reactive substances (TBARS), total glutathione (GSHt), and trolox equivalent antioxidant capacity (TEAC) in 10 race horses. Different sampling times [immediately before training (BEF) and after intense training (END) or 8 h after recovery (+8h)] were investigated. Plasma α-tocopherol concentration was greater in the ST-VitE group than the CONTROL group at +8h (P < 0.05). Natural vitamin E supplementation increased plasma α-tocopherol (P < 0.001) in the LT-VitE group by approximately 1.6-fold at BEF, END, and +8h. In all groups, TBARS tended to be slightly greater (P = 0.087) immediately after training when compared with values BEF or +8h and the lowest TBARS values were observed at +8h in LT-VitE. Vitamin E supplementation did not affect the GSHt concentrations at BEF, END, or +8h. The TEAC values were modified by the vitamin E administration (P = 0.010). The greatest TEAC was found in the LT-VitE group at all sampling times and similar concentrations were reached in the ST-VitE group at +8h. The CONTROL group was not able to maintain TEAC after training (P < 0.001), indicating consumption of antioxidants (mainly vitamin E) and consequently oxidative stress because of the antioxidant system being overwhelmed by a reduced antioxidant supply. In conclusion, micellized natural vitamin E at 1,400 IU/d for 8 d efficiently increased plasma α-tocopherol concentration of race horses undergoing intense training conditions and maintained the general oxidative status.

Antioxidant status in elite three-day event horses during competition

The objective of this study was to determine if competition intensity would have an effect on antioxidant status in horses before and during a three-day event. Body weight, body condition score, and blood was sampled from CCI2* (n = 19) and CCI3* (n = 23) horses before the start of dressage, 20 to 30 min following cross-country, and 18–24 h after cross-county. Data were analyzed using a PROC MIXED in SAS. There were no differences between CCI2* and CCI3* horses during competition for plasma cortisol, lactate, α-tocopherol, retinol, or erythrocyte glutathione peroxidase. After cross-country, CCI3* horses had higher serum creatine kinase (P = 0.003) and aspartate aminotransferase (P < 0.0001) than the CCI2* horses. Plasma β-carotene was higher in the CCI2* horses compared to the CCI3* horses (P = 0.0001). Total erythrocyte glutathione was also higher in the CCI2* horses versus CCI3* horses (P < 0.0001). These results are the first report of antioxidant status of horses competing in this level of a three-day event. The changes in antioxidant and muscle enzymes observed between divisions are likely due to the increased anaerobic and musculoskeletal demand on the upper level horses and the fitness required to compete at that level.