Entrenamiento y adaptación muscular: sustratos y vías metabólicas para la producción de energía

Three isoforms of MyHc have been characterized in the skeletal muscle of adult equines at the proteins level: types I, IIA and IIX. The distribution of these MyHCs defines three pure kinds of fibre which contain a single isoform (I+IIA and IIAX). The hybrid fibres IIAX exist in the locomotive muscles as a permanent and significant population. The adjusting response may take different forms depending on the nature of the stimulus: hypertrophy, reorganization (restructuring) without hypertrophy and a combined answer, when restructuring joins hypertrophy. The equines may take the most of different energetic subtrates, some of which are used immediately after the ingest, while others are stored in the liver, the muscles or adipose tissue in order to be used later. The muscular glycogen and the glucose may be degraded aerobically through the aerobic pathway or through the anaerobic pathway, while in the endurance exercises the use of fatty acids is accomplished from the degradation of fat stored in the subcutaneous cellular tissue. The oxidative metabolism measures the function of the cardiovascular and respiratory systems. On the contrary, the anaerobic metabolism involves only the muscular tissue.Tres isoformas de MyHC han sido caracterizadas en músculo esquelético de equinos adultos a nivel proteico: tipo I, IIA y IIX. La distribución de estas MyHCs definen tres tipos puros de fibras que contienen una sola isoforma (tipo I, IIA y IIX) y dos tipos de fibras híbridas que expresan dos isoformas (I+IIA y IIAX). Las fibras híbridas IIAX existen en los músculos locomotores como una población estable y significativa. Dependiendo de la naturaleza del estímulo, la respuesta adaptativa puede tomar diferentes formas: hipertrofia, remodelación sin hipertrofia y respuesta mixta, cuando se combina la remodelación con la hipertrofia. Los equinos pueden aprovechar diferentes sustratos energéticos, algunos de los cuales son utilizados en forma inmediata tras la ingesta, mientras que otros son almacenados en el hígado, músculos y tejido adiposo para ser usados en otro momento. El glucógeno muscular y la glucosa pueden ser degradados por la vía aeróbica (oxidativa) o la anaeróbica lactacida (glucolítica), mientras que en ejercicios de resistencia la utilización de ácidos grasos se realiza a partir de la degradación de triglicéridos almacenados en el tejido celular subcutáneo. El metabolismo oxidativo mide la función de los sistemas cardiovascular y respiratorio. En cambio, el metabolismo anaeróbico solo involucra al tejido muscular.Facultad de Ciencias Veterinaria

Entrenamiento y adaptación muscular: sustratos y vías metabólicas para la producción de energía

Three isoforms of MyHc have been characterized in the skeletal muscle of adult equines at the proteins level: types I, IIA and IIX. The distribution of these MyHCs defines three pure kinds of fibre which contain a single isoform (I+IIA and IIAX). The hybrid fibres IIAX exist in the locomotive muscles as a permanent and significant population. The adjusting response may take different forms depending on the nature of the stimulus: hypertrophy, reorganization (restructuring) without hypertrophy and a combined answer, when restructuring joins hypertrophy. The equines may take the most of different energetic subtrates, some of which are used immediately after the ingest, while others are stored in the liver, the muscles or adipose tissue in order to be used later. The muscular glycogen and the glucose may be degraded aerobically through the aerobic pathway or through the anaerobic pathway, while in the endurance exercises the use of fatty acids is accomplished from the degradation of fat stored in the subcutaneous cellular tissue. The oxidative metabolism measures the function of the cardiovascular and respiratory systems. On the contrary, the anaerobic metabolism involves only the muscular tissue.Tres isoformas de MyHC han sido caracterizadas en músculo esquelético de equinos adultos a nivel proteico: tipo I, IIA y IIX. La distribución de estas MyHCs definen tres tipos puros de fibras que contienen una sola isoforma (tipo I, IIA y IIX) y dos tipos de fibras híbridas que expresan dos isoformas (I+IIA y IIAX). Las fibras híbridas IIAX existen en los músculos locomotores como una población estable y significativa. Dependiendo de la naturaleza del estímulo, la respuesta adaptativa puede tomar diferentes formas: hipertrofia, remodelación sin hipertrofia y respuesta mixta, cuando se combina la remodelación con la hipertrofia. Los equinos pueden aprovechar diferentes sustratos energéticos, algunos de los cuales son utilizados en forma inmediata tras la ingesta, mientras que otros son almacenados en el hígado, músculos y tejido adiposo para ser usados en otro momento. El glucógeno muscular y la glucosa pueden ser degradados por la vía aeróbica (oxidativa) o la anaeróbica lactacida (glucolítica), mientras que en ejercicios de resistencia la utilización de ácidos grasos se realiza a partir de la degradación de triglicéridos almacenados en el tejido celular subcutáneo. El metabolismo oxidativo mide la función de los sistemas cardiovascular y respiratorio. En cambio, el metabolismo anaeróbico solo involucra al tejido muscular.Facultad de Ciencias Veterinaria

Entrenamiento y adaptación muscular: sustratos y vías metabólicas para la producción de energía

Three isoforms of MyHc have been characterized in the skeletal muscle of adult equines at the proteins level: types I, IIA and IIX. The distribution of these MyHCs defines three pure kinds of fibre which contain a single isoform (I+IIA and IIAX). The hybrid fibres IIAX exist in the locomotive muscles as a permanent and significant population. The adjusting response may take different forms depending on the nature of the stimulus: hypertrophy, reorganization (restructuring) without hypertrophy and a combined answer, when restructuring joins hypertrophy. The equines may take the most of different energetic subtrates, some of which are used immediately after the ingest, while others are stored in the liver, the muscles or adipose tissue in order to be used later. The muscular glycogen and the glucose may be degraded aerobically through the aerobic pathway or through the anaerobic pathway, while in the endurance exercises the use of fatty acids is accomplished from the degradation of fat stored in the subcutaneous cellular tissue. The oxidative metabolism measures the function of the cardiovascular and respiratory systems. On the contrary, the anaerobic metabolism involves only the muscular tissue.Tres isoformas de MyHC han sido caracterizadas en músculo esquelético de equinos adultos a nivel proteico: tipo I, IIA y IIX. La distribución de estas MyHCs definen tres tipos puros de fibras que contienen una sola isoforma (tipo I, IIA y IIX) y dos tipos de fibras híbridas que expresan dos isoformas (I+IIA y IIAX). Las fibras híbridas IIAX existen en los músculos locomotores como una población estable y significativa. Dependiendo de la naturaleza del estímulo, la respuesta adaptativa puede tomar diferentes formas: hipertrofia, remodelación sin hipertrofia y respuesta mixta, cuando se combina la remodelación con la hipertrofia. Los equinos pueden aprovechar diferentes sustratos energéticos, algunos de los cuales son utilizados en forma inmediata tras la ingesta, mientras que otros son almacenados en el hígado, músculos y tejido adiposo para ser usados en otro momento. El glucógeno muscular y la glucosa pueden ser degradados por la vía aeróbica (oxidativa) o la anaeróbica lactacida (glucolítica), mientras que en ejercicios de resistencia la utilización de ácidos grasos se realiza a partir de la degradación de triglicéridos almacenados en el tejido celular subcutáneo. El metabolismo oxidativo mide la función de los sistemas cardiovascular y respiratorio. En cambio, el metabolismo anaeróbico solo involucra al tejido muscular.Facultad de Ciencias Veterinaria

Green route for the isolation and purification of hyrdoxytyrosol, tyrosol, oleacein and oleocanthal from extra virgin olive oil

Extra virgin olive oil (EVOO) phenols represent a significant part of the intake of antioxidants and bioactive compounds in the Mediterranean diet. In particular, hydroxytyrosol (HTyr), tyrosol (Tyr), and the secoiridoids oleacein and oleocanthal play central roles as anti-inflammatory, neuro-protective and anti-cancer agents. These compounds cannot be easily obtained via chemical synthesis, and their isolation and purification from EVOO is cumbersome. Indeed, both processes involve the use of large volumes of organic solvents, hazardous reagents and several chromatographic steps. In this work we propose a novel optimized procedure for the green extraction, isolation and purification of HTyr, Tyr, oleacein and oleocanthal directly from EVOO, by using a Natural Deep Eutectic Solvent (NaDES) as an extracting phase, coupled with preparative high-performance liquid chromatography. This purification method allows the total recovery of the four components as single pure compounds directly from EVOO, in a rapid, economic and ecologically sustainable way, which utilizes biocompatible reagents and strongly limits the use or generation of hazardous substances

Effects of chemical ischemia on purine nucleotides, free radical generation, lipids peroxidation and intracellular calcium levels in C 2C12 myotube derived from mouse myocytes

To elucidate the mechanisms of ischemia-mediated myopathy using in vitro model, changes of purine nucleotides, membrane lipid peroxidation(TBARS), intracellular calcium ([Ca2+]i)levels, generation of free radicals, and deoxyribonucleic acid (DNA) fragmentation were examined in mouse-derived C2C12 myotubes under the condition with an inhibition of glycolytic and oxidative metabolism as the ischemic condition. In purine nucleotides, intracellular adenosine triphosphate (ATP) and guanosine triphosphate (GTP) concentrations rapidly and significantly decreased after the treatment with ischemia. No remarkable differences were observed in other purine nucleotides, with the exception of inosine monophosphate (IMP) and extracellular hypoxanthine levels, both of which increased significantly during the ischemia. The lactate dehydrogenase activity in culture supernatant of C2C12 myotubes increased significantly from 2 to 4 hr after the ischemia. On the generation of free radicals, no spectrum was detected in supernatants throughout the observation period, whereas supernatant TBARS concentration increased rapidly and significantly after the ischemia. The relative intensity of [Ca2+]i significantly increased after the ischemia. On the fragmented deoxyribonucleic acid(DNA), no TUNEL positive cells was detected in C2C12 myotubes after 1 hr of the ischemia, however the positive cell percentage subsequently increased. From these results, it was suggested that the ischemic condition induced changes of membrane permeability and increase of [Ca2+]i, both of which lead to cell membrane damage, although a free radical generation was not detected. The ischemic condition also induced the release of substrate hypoxanthine for free radical generation and might initiate the apoptotic pathway in C2C12 myotubes.Facultad de Ciencias Veterinaria

Relationship between Resting and Recovery Heart Rate in Horses

In endurance racing the heart rate (HR) of horses in the veterinary gates has to reach a maximum set to continue racing. There is no literature on the relationship between resting HR (HRresting) and HR after exercise (HRrecovery). This relationship was examined in seven horses and the results were related to their v4 (speed at which the blood lactate concentration is 4 mmol/L). Horses were submitted to an exercise test to determine v4. Thereafter, horses were exercised on a treadmill in randomized order for 10 and 60 min at different speeds. HR was measured before exercise and several times until 30 min of recovery. The relationship between HRresting and HRrecovery was significant in 16 out of 35 comparisons. There were no significant relationships between the v4 of the horses and their HRresting and between v4 and HRrecovery after 10 min of exercise, regardless of the speed of exercise, with one exception. The relationship between the v4 of the horses and their HRrecovery after 60 min of exercise was significant in the fifth minute after exercise at 3.5 m/s only. Conclusion: Because HRresting and HRrecovery are often related, pre-determined arbitrary HRrecovery values may not allow for fair competition during endurance racing.Facultad de Ciencias Veterinaria

Effects of chemical ischemia on purine nucleotides, free radical generation, lipids peroxidation and intracellular calcium levels in C 2C12 myotube derived from mouse myocytes

To elucidate the mechanisms of ischemia-mediated myopathy using in vitro model, changes of purine nucleotides, membrane lipid peroxidation(TBARS), intracellular calcium ([Ca2+]i)levels, generation of free radicals, and deoxyribonucleic acid (DNA) fragmentation were examined in mouse-derived C2C12 myotubes under the condition with an inhibition of glycolytic and oxidative metabolism as the ischemic condition. In purine nucleotides, intracellular adenosine triphosphate (ATP) and guanosine triphosphate (GTP) concentrations rapidly and significantly decreased after the treatment with ischemia. No remarkable differences were observed in other purine nucleotides, with the exception of inosine monophosphate (IMP) and extracellular hypoxanthine levels, both of which increased significantly during the ischemia. The lactate dehydrogenase activity in culture supernatant of C2C12 myotubes increased significantly from 2 to 4 hr after the ischemia. On the generation of free radicals, no spectrum was detected in supernatants throughout the observation period, whereas supernatant TBARS concentration increased rapidly and significantly after the ischemia. The relative intensity of [Ca2+]i significantly increased after the ischemia. On the fragmented deoxyribonucleic acid(DNA), no TUNEL positive cells was detected in C2C12 myotubes after 1 hr of the ischemia, however the positive cell percentage subsequently increased. From these results, it was suggested that the ischemic condition induced changes of membrane permeability and increase of [Ca2+]i, both of which lead to cell membrane damage, although a free radical generation was not detected. The ischemic condition also induced the release of substrate hypoxanthine for free radical generation and might initiate the apoptotic pathway in C2C12 myotubes.Facultad de Ciencias Veterinaria

Ventilatory equivalent in the horse

Se evaluaron e interpretaron las modificaciones del equivalente ventilatorio para el oxígeno (VE/VO2), producidas por una carga de trabajo hasta fatiga en seis equinos sangre pura de carrera (SPC). Los equinos fueron ejercitados con una carga de trabajo escalonada hasta 15 metros por segundo, con un 3% de pendiente, sobre una cinta ergométrica (Mustang 2200) y el VE/VO2 se registró con una máscara facial y dos sensores ultrasónicos conectados a un ergoespirómetro (Metasoft modelo Cortex Biofisyc ®). Nuestros resultados, indican diferencias estadísticamente significativas (P2. Cuando las cargas de trabajo que se comparan son de similar intensidad (10.5 a 15 m/s), las diferencias dejan de ser estadísticamente significativas (P>0,05). Los resultados revelan, que el VE/VO2 en los SPC, sufre modificaciones producidas por una carga de trabajo escalonada hasta fatiga y se comportaría de forma diferente a lo reportado por la bibliografía para los seres humanos. La diferencia en los equinos radica en que una vez superado el 60% del consumo máximo de oxígeno (VO2max), el VE/ VO2 sigue disminuyendo y no aumenta como sucede en los humanos, esto demostraría una mayor eficiencia en el intercambio gaseoso en los equinos.SThe evaluation and interpretation of ventilatory equivalent for oxygen (VE/VO2) was made in six horses. The horses were exercised strenuously until 15 meters per second (m/s) on a treadmill, and the VE/VO2 was registered with an ergospyrometer Metasoft model Cortex Biofisyc. The values were significantly dependent on the workload (P2 within similar work intensities, starting at 6.5 m/s and until 4 m/s during cold down, no significant differences were found. VE/VO2 values in horses in the present study are different than those reported in humans. As a major difference with humans, a diminution in the VE/VO2 values was maintained even after a 60 % of the VO2 max was reached.Facultad de Ciencias Veterinaria

DNA damage in leukocytes of equines subjected to physical effort

En los últimos años se ha observado un creciente interés por el estudio de los efectos beneficiosos y perjudiciales asociados al ejercicio. El objetivo del presente trabajo fue establecer la existencia de daño en el ADN en leucocitos circulantes de equinos sometidos a un test de ejercicio de alta intensidad y corta duración. La determinación del daño en el ADN se realizó mediante el ensayo cometa versión alcalina. Se usaron 5 equinos. Se extrajeron muestras de sangre al comenzar el ejercicio, al alcanzar la velocidad máxima, al finalizar el ejercicio y a los 30 días post ejercicio. Simultáneamente se realizaron ergoespirometrías continuas para determinar el consumo de oxígeno durante el ejercicio. La frecuencia relativa de células con daño en el ADN fue 0,122, 0,240, 0,210 y 0,100, mientras que el índice de daño en el ADN fue 11,8, 28,4, 23 y 10,4 UA. Se observaron incrementos significativos con respecto al tiempo basal y 30 días post ejercicio cuando los animales alcanzaron la máxima velocidad y al finalizar el ejercicio (p< 0,05). Se observó una alta correlación entre el consumo de oxígeno y las células con daño (r= 0,905), así como con el índice de daño (r= 0,935). Estos resultados sugieren que los factores inductores de daño genotóxico se producen mayoritariamente durante el esfuerzo físico y que probablemente se deban a radicales libres del oxígeno.In recent years there has been a growing interest in the study of the beneficial and harmful effects associated with exercise. The aim of this study was to establish the existence of DNA damage in circulating leukocytes of horses undergoing high intensity and short term physical activity by using the alkaline comet assay. Five horses subjected to a standardized exercise test were used. Samples were collected before starting the exercise, at the point of reaching maximal speed, at the end of the test and 30 days post exercise. Simultaneously, oxygen consumption during the exercise test was measured. The relative frequency of cells with DNA damage was 0.122, 0.240, 0.210 and 0.100, respectively. DNA damage index was 11,8, 28,4, 23 and 10,4 UA, respectively. Significant increases were observed from baseline time and 30 days after exercise when the animals reached maximum speed and at the end of the exercise (p< 0.05). These results suggest that genotoxic damage inducing factors occur mainly during physical fatigue, and that this is probably due to oxygen free radicals.Facultad de Ciencias Veterinaria

DNA damage in leukocytes of equines subjected to physical effort

En los últimos años se ha observado un creciente interés por el estudio de los efectos beneficiosos y perjudiciales asociados al ejercicio. El objetivo del presente trabajo fue establecer la existencia de daño en el ADN en leucocitos circulantes de equinos sometidos a un test de ejercicio de alta intensidad y corta duración. La determinación del daño en el ADN se realizó mediante el ensayo cometa versión alcalina. Se usaron 5 equinos. Se extrajeron muestras de sangre al comenzar el ejercicio, al alcanzar la velocidad máxima, al finalizar el ejercicio y a los 30 días post ejercicio. Simultáneamente se realizaron ergoespirometrías continuas para determinar el consumo de oxígeno durante el ejercicio. La frecuencia relativa de células con daño en el ADN fue 0,122, 0,240, 0,210 y 0,100, mientras que el índice de daño en el ADN fue 11,8, 28,4, 23 y 10,4 UA. Se observaron incrementos significativos con respecto al tiempo basal y 30 días post ejercicio cuando los animales alcanzaron la máxima velocidad y al finalizar el ejercicio (p< 0,05). Se observó una alta correlación entre el consumo de oxígeno y las células con daño (r= 0,905), así como con el índice de daño (r= 0,935). Estos resultados sugieren que los factores inductores de daño genotóxico se producen mayoritariamente durante el esfuerzo físico y que probablemente se deban a radicales libres del oxígeno.In recent years there has been a growing interest in the study of the beneficial and harmful effects associated with exercise. The aim of this study was to establish the existence of DNA damage in circulating leukocytes of horses undergoing high intensity and short term physical activity by using the alkaline comet assay. Five horses subjected to a standardized exercise test were used. Samples were collected before starting the exercise, at the point of reaching maximal speed, at the end of the test and 30 days post exercise. Simultaneously, oxygen consumption during the exercise test was measured. The relative frequency of cells with DNA damage was 0.122, 0.240, 0.210 and 0.100, respectively. DNA damage index was 11,8, 28,4, 23 and 10,4 UA, respectively. Significant increases were observed from baseline time and 30 days after exercise when the animals reached maximum speed and at the end of the exercise (p< 0.05). These results suggest that genotoxic damage inducing factors occur mainly during physical fatigue, and that this is probably due to oxygen free radicals.Facultad de Ciencias Veterinaria