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Homocysteine is an indirect metabolite of methionine metabolism, as well as of creatinine, and it plays an important role in many biochemical processes. Physical effort modifies homocysteine concentration in the blood, as well as the substances taking part in its metabolism. The aim of the study was to assess the influence of intensive efforts of diverse energy changes on the concentrations of homocysteine and the vitamins involved in its metabolism – vit. B6, vit. B12 and folic acid. In the study athletes performed Wingate and progressive test. Before and after tests homocysteine, vitamins B6, B12 and folic acid and creatinine were assayed. Concentration of homocysteine, vit. B12 and creatinine in the blood increased after both tests. Concentration of vit. B6 decreased and folic acid increased after Wingate test while they did not change after a progressive test. Homocysteine concentration negatively correlated with folic acid but positively with creatinine concentration in the blood, as well as with LBM. Regardless of its duration and energetic changes, intensive effort leads to an increase in homocysteine concentration. Correlation of homocysteine with creatinine and the LBM suggest that people with bigger muscle mass can have higher homocysteine concentration in the blood.
The aim of this study was to investigate whether the oxidative stress may be the reason for apoptosis in skeletal muscles in rats. Rats were divided into two groups - controls and exposed to physical exercise. Rats were running on the treadmill at the speed of 1km/h until exhaustion. After the exercise, the concentration of lipid peroxidation markers - malonylodialdehyde and 4- hydroxyalkenes (MDA+4-HDA), and the level of reduced glutathione (GSH) was determined in the homogenates of the extensor digitorum longus (EDL) muscle and slow-twitch (ST) fibres in 2, 6, and 96 h of restitution. Aconitase activity as a marker of oxidative protein modification was determined in ST fibres and EDL muscle. Additionally, apoptosis was detected by the TUNEL technique. A significant increase in MDA+4HDA concentrations in comparison to the control group was noticed in both ST fibres and EDL muscle after 6 h. GSH concentration in 2 and 6 h after exercise was significantly decreased in ST fibres and in EDL muscle in all measurements, when compared to the control group. Aconitase activity in ST fibres and EDL muscle was also significantly decreased 2 h after the exercise when compared to the control group, but increased in 6 h of restitution. Apoptotically-changed nuclei were observed only in EDL fibres. On the basis of the results and the suggested mechanism, it can be thought that the oxidative stress triggers apoptosis in ST fibres and in EDL muscle after exercise and it starts in the mitochondria.
The aim of the research was to assess changes in ghrelin, leptin and free fatty acids (FFA) levels in women’s blood after training. The research was carried out in women aged 45.55 ±11.33 years and with the BMI of 26.49 ±4.49. Health training at 50–66% VO2max took place twice a week for 9 months. In the baseline phase and in the 3rd, 6th and 9th month of the training, body mass and composition were measured, cardiorespiratory fitness was checked after a 10-minute exercise test on a cycloergometer, and fasting levels of ghrelin, leptin and FFA in the serum were assayed and 15 minutes after the exercise test. Body mass was reduced in the 6th month of the training. Fasting ghrelin level increased because of training, leptin and FFA decreased. After single 10-minute exercises performed every 3 months level of ghrelin and FFA increased while leptin decreased. An increase in ghrelin level in the blood after the single exercise can be the result of negative energy expenditure. An increase in fasting ghrelin level after training can be one of the adaptive physiological mechanisms connected with energy saving. A mechanism that is switched on as a result of a long-lasting stimulus that leads to energy losses, reduction in body mass and a decrease in leptin level in the blood.
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Melatonin decreases homocysteine level in blood of rats

39%
Elevated plasma homocysteine level promotes atherosclerosis in blood vessels due to, among others, generation of reactive oxygen species and reduction of nitric oxide bioavailability. The aim of this study was to investigate whether melatonin administration reduces plasma homocysteine level in rats consuming increased doses of methionine in the diet. The trial lasted for two months. The rats were divided into a few groups - 2 groups consisted of animals fed a standard diet, 2 groups consisted of animals fed a diet rich in methionine for one and two months, a group which had methionine removed from the diet in the second month, a group which had methionine removed from the diet and melatonin administered in the second month, a group still fed a diet rich in methonine in the second month and also given melatonin, and a group of animals on a diet rich in methionine for two months and given melatonin at the same time. Hcy, lipid peroxidation markers (MDA+4HNE) and nitric oxide metabolite (NO2-/NO3-) concentrations were determined in the plasma of all the rats. As a result of the tests it was found that plasma Hcy concentration increases in the first month of a methionine-rich diet but then decreases in the second month. MDA+4HNE changes are similar. Melatonin significantly intensifies the effects. The changes of NO2-/NO3- concentrations were noticed especially in the groups receiving melatonin. Elimination of methionine from the feed does not change the value of NO2-/NO3-. NO production increases only after administration of melatonin. On the basis of received results it might be stated that melatonin administration together with a methionine-rich diet significantly decreases Hcy concentration, the level of oxidative stress and increases NO production. It might have some practical implications, especially when the level of endogenous melatonin decreases e.g. in elderly people or people with hyperhomocysteinemia.
The significance of mangane as an environmental pollutant has increased in previous years. In this study the authors present the influence of chronic exposure of mangane on oxidative stress parameters. Depending on the position in the brain, the authors observed the following changes: decrease of GPx and GR activity in the brain stem, similarly in the cerebellum; in the brain’s hemispheres, however, an increase of GST activity and a decrease of GR activity was observed. CAT activity in all these three structures remained at a lower, constant level.
A number of studies have shown that acute physical exercise is associated with the induction of apoptosis not only in skeletal muscle but also in many distant organs. One of the pathogenic agents responsible for exercise-induced damage in many tissues is the generation of oxygen free radicals. The aim of the present study was to examine the influence of exercise-induced oxidative stress on the rat kidney. The analysis was performed on the kidneys of rats subjected to treadmill running until exhaustion. Our results demonstrated that acute exercise led to apoptotic damage of the renal distal tubular cells, although this was not a result of oxidative stress.
Angiotensin converting enzyme gene (ACE) is the most frequently investigated genetic marker in the context of genetic conditioning of athletic predispositions. However, the knowledge of ACE’s potential modifying effect on changes in selected body traits achieved through a training programme is still limited. Therefore, we have decided to check whether selected body mass, body composition variables, oxygen uptake parameters as well as strength/speed parameters observed in physically active participants will be modulated by the ACE I/D polymorphism. The genotype distribution was examined in a group of 201 young healthy women measured for chosen traits before and after the completion of a 12-week moderate-intensive aerobic training programme. Our results revealed the significant genotype × training interactions for VEmax and power of countermovement jump, whereas training improvements were demonstrated for almost all parameters. In addition, main effects of the ACE I/D genotype on TGL, HDL, glucose and 10 m run were observed. A significant increase in VEmax was demonstrated for II and DD genotypes, but not for ID heterozygotes. The greatest gain in power of countermovement jump was observed in II homozygotes, although DD and ID were associated with a significant increase as well. Our study indicated that the polymorphism was associated with changes in VEmax and power of countermovement jump in response to a 12-week aerobic training programme in Caucasian women. However, more experimental studies are needed to establish the ACE gene × physical activity interactions.
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