Four groups of goldfish were exposed to cadmium in a concentration of 20 mg Cd/l water under aquarium conditions. The duration of exposure was 1, 4, 7 and 15 days. It was shown that the activity of superoxide dismutase (SOD) in the red blood cells (RBC) significantly decreased after the first day of cadmium exposure. However, the SOD activity increased after 7 and 15 days of cadmium treatment. Elevated activity of catalase (CAT) was found in erythrocytes of cadmium-treated fishes after 15 days, whereas plasma GOT levels was increased after 7 and 15 days and GPT levels after 1, 4, 7 and 15 days of cadmium treatment. This was accompanied by a significant decrease of blood hemoglobin concentrations (after 15 days) and hematocrit values (after 7 and 15 days). However, the concentration of blood glucose significantly increased after 1, 4, 7 and 15 days of cadmium exposure. These results indicate that cadmium causes oxidative stress and tissue damage in the exposed fishes., R.V. Žikić, A. Š. Štajn, S. Z. Pavlović, B. I. Ognjanović, Z. S. Saičić., and Obsahuje bibliografii
Paraoxonase 1 (PON1) seems to have a relevant role in detoxifying processes and in atherosclerosis. The aim of this study was to determine PON1 activity, the total antioxidant capacity, as well as entire lipid profile in children for screening of possible risk of atherosclerosis development. Serum PON1 arylesterase/paraoxonase activities were determined spectrophotometrically. The total antioxidant capacity of the serum was measured by TEAC method. Parameters of lipid profile were analyzed by routine laboratory methods. It has been shown that PON1 arylesterase/ paraoxonase activities were very similar to values found in adults. In children, no significant correlation between PON1 arylesterase activity and HDL was observed. PON1 paraoxonase activity correlated only with atherogenic index. PON1 arylesterase activity was significantly higher in girls than in boys. The antioxidant capacity was inversely related to the body mass index. In this study, PON1 activity was determined in healthy children aged 11 to 12 years and we found a similarity in PON1 activities of children and adults. Moreover, the results of our study support the hypothesis that higher body weight of children may contribute to a greater risk for development of atherosclerosis in which oxidative stress plays a role., K. Sumegová, Z. Nagyová, I. Waczulíková, I. Žitňanová, Z. Ďuračková., and Obsahuje bibliografii a bibliografické odkazy
We studied the temporal relationships and the patterns of electromyographic activities of the posterior cricoarytenoid and thyreoarytenoid muscles (laryngeal abductor and adductor), the diaphragm and abdominal muscles in anesthetized cats during mechanically induced tracheobronchial and laryngopharyngeal coughs, expiration and aspiration reflexes. The posterior cricoarytenoid muscle activity reached the maxima just before the peak of diaphragmatic activity in both types of cough and aspiration reflexes and slightly before the top of abdominal muscle activity in coughs and the expiration reflex. Thus, this muscle contributes to the inspiratory phase of coughs and aspiration reflex and also to the expulsive phase of coughs and the expiration reflex. The thyreoarytenoid muscle presented strong discharges in the compressive phase of coughs and expiration reflex (during the rising part of the abdominal muscle activity) and in the subsequent laryngoconstriction (following the diaphragmal and/or abdominal muscle activity) in all four reflexes. This muscle was also slightly activated at the beginning of the aspiration reflex. The existence of four phases of the cough reflex is also discussed., I. Poliaček, A. Stránsky, J. Jakuš, H. Baráni, Z. Tomori, E. Halašová., and Obsahuje bibliografii
Recovery from exercise refers to the period between the end of a bout of exercise and the subsequent return to a resting or recovered state. It is a dynamic period in which many physiological changes occur. A large amount of research has evaluated the effect of training on intramuscular lipid metabolism. However, data are limited regarding intramuscular lipid metabolism during the recovery period. In this study, lipid metabolism-related proteins were examined after a single bout of exercise in a time-dependent way to explore the mechanism of how exercise induces intramuscular lipid metabolism adaptation. Firstly, all rats in the exercise group underwent a five-week training protocol (HIIT, five times/week), and then performed a more intense HIIT session after 72 h of the last-time five-week training. After that, rats were sampled in a time-dependent way, including 0 h, 6 h, 12 h, 24 h, 48 h, 72 h, and 96 h following the acute training session. Our results discovered that five weeks of HIIT increased the content of intramuscular triglyceride (IMTG) and enhanced the lipolytic and lipogenesis-related proteins in skeletal muscle. Furthermore, IMTG content decreased immediately post HIIT and gradually increased to baseline levels 48 h postexercise, continuing to over-recover up to 96 h postexercise. Following acute exercise, lipolytic-related proteins showed an initial increase (6-12 h) before decreasing during recovery. Conversely, lipogenesis-related proteins decreased following exercise (6-12 h), then increased in the recovery period. Based on the changes, we speculate that skeletal muscle is predominated by lipid oxidative at the first 12 h postexercise. After this period, lipid synthesis-related proteins increased, which may be the result of body recovery. Together, these results may provide insight into how the lipid metabolism-related signaling changes after chronic and acute HIIT and how protein levels lipid metabolism correlates to IMTG recovery., Min Chen, Lei Zhou, Siyu Chen, Ruonan Shangguan, Yaqian Qu, Jingquan Sun., and Obsahuje bibliografii
The biosynthesis and metabolism of testosterone and cortisol are altered by the high levels of adipose tissue and the constant state of low-grade inflammation of obesity. Resistance exercise (REx) has become one of the main lifestyle interventions prescribed to obese individuals due to its ability to positively influence body composition and some biomarkers, such as cholesterol and insulin resistance. Yet, little research has been done in obese examining the effects of REx on the testosterone and blood cortisol responses, two integral hormones in both exercise and obesity. The obese testosterone response to REx and whether or not it is blunted compared to lean individuals remains elusive. Conflicting findings concerning the blood cortisol response have also been reported, likely due to variance in REx protocol and the level of obesity in the participants in studies. Comparatively, both of these hormones have been extremely well studied in untrained lean males, which could be used as a basis for future research in obese males. However, without this endocrinological information, it is unknown if the current acute REx prescriptions are appropriate for eliciting a favorable acute endocrinological response, and ultimately, a positive chronic adaptation in obese males., C. B. O'Leary, A: C. Hackney., and Obsahuje bibliografii
Principal vasoactive systems - renin-angiotensin system (RAS), sympathetic nervous system (SNS), nitric oxide (NO) and prostanoids - exert their vascular effects through the changes in calcium levels and/or calcium sensitization. To estimate a possible modulation of calcium sensitization by the above vasoactive systems, we studied the influence of acute and chronic blockade of particular vasoactive systems on blood pressure (BP) changes elicited in conscious normotensive rats by acute dose-dependent administration of Rho-kinase inhibitor fasudil. Adult male chronically cannulated Wistar rats were used throughout this study. The acute inhibition of NO synthase (NOS) by L-NAME enhanced BP response to fasudil, the effect being considerably augmented in rats deprived of endogenous SNS. The acute inhibition of prostanoid synthesis by indomethacin modified BP response to fasudil less than the acute NOS inhibition. The chronic NOS inhibition caused moderate BP elevation and a more pronounced augmentation of fasudilinduced BP changes compared to the effect of acute NOS inhibition. This indicates both short-term and long-term NOdependent attenuation of calcium sensitization. Long-term inhibition of RAS by captopril caused a significant attenuation of BP changes elicited by fasudil. In contrast, a long-term attenuation of SNS by chronic guanethidine treatment (in youth or adulthood) had no effect on BP response to fasudil, suggesting the absence of SNS does not affect calcium sensitization in vascular smooth muscle of normotensive rats. In conclusion, renin-angiotensin system contributes to the long-term increase of calcium sensitization and its effect is counterbalanced by nitric oxide which decreases calcium sensitization in Wistar rats., A. Brunová, M. Bencze, M. Behuliak, J. Zicha., and Obsahuje bibliografii
Natural glucocorticoid hydrocortisone was suggested as a potent substitution for dexamethasone in the treatment of bronchopulmonary dysplasia in neonates. The aim of this study was to investigate whether hydrocortisone is able to affect the expression of apoptotic genes and the intensity of naturally occurring cell death in the developing rat hippocampus. Hormone treatment decreased procaspase-3 and active caspase-3 levels as well as DNA fragmentation intensity in the hippocampal formation of one-week-old rats in 6 h after injection. These changes were accompanied by an upregulation of antiapoptotic protein Bcl-XL, while expression of proapoptotic protein Bax remained unchanged. The action of hydrocortisone was glucocorticoid receptor-independent, as the selective glucocorticoid receptor agonist dexamethasone did not affect either apoptotic protein levels or DNA fragmentation intensity in the hippocampal region. The data are the first evidences for in vivo antiapoptotic effects of hydrocortisone in the developing hippocampus., P. N. Menshanov, ... [et al.]., and Obsahuje seznam literatury
Cadmium (Cd), an environmental and industrial pollutant, poses a potential threat and affects many systems in human and animals. Although several reports on Cd toxicity were presented, the acute effect of Cd on systemic and thrombotic events was not reported so far. Cd (2.284 mg/kg) or saline (control) was injected intraperitoneally (ip), and the systemic parameters were assessed in mice. Compared to control group, acute intraperitoneal injection of Cd, in mice showed significant quickening of platelet aggregation (P<0.001) leading to pial cerebral thrombosis. Likewise, Cd exposure caused a significant increase in white blood cell numbers (P<0.05) indicating the occurrence of systemic inflammation. Also, alanine aminotransferase (ALT) (P<0.05) and creatinine (P<0.01) levels were both significantly increased. Interestingly, the superoxide dismutase activity was significantly decreased in Cd treated group compared to control group (P<0.001), suggesting the occurrence of oxidative stress. We conclude that the Cd exposure in mice causes acute thromboembolic events, oxidative stress and alter liver and kidney functions., M.A. Fahim ... [et al.]., and Obsahuje seznam literatury
Parallel glucose measurements in blood and other different tissues give us knowledge about dynamics of glycemia changes, which depend on vascularization, distribution space and local utilization by tissues. Such information is important for the understanding of glucose homeostasis and regulation. The aim of our study was to determine the time-lag between blood, brain, and adipose tissue during rapid glucose changes in a male hHTG rat (n=15). The CGMS sensor Guardian RT (Minimed/Medtronic, USA) was inserted into the brain and into the abdominal subcutaneous tissue. Fixed insulin and variable rate of glucose infusion was used to maintain euglycemia during sensor calibration period. At 0 min, 0.5 g/kg of bolus of glucose was administered, and at 50 min, 5 IU/kg of bolus of insulin was administered. Further glucose and insulin infusion was stopped at this time. The experiment was finished at 130 min and animals were euthanized. The time-shift between glycemia changes in blood, brain, and subcutaneous tissue was calculated by identification of the ideal correlation function. Moreover, the time to achieve 90 % of the maximum glucose excursion after intervention (T90) was measured to compare our data with the literature. The time-lag blood vs. brain and blood vs. subcutaneous tissue was 10 (10; 15) min and 15 (15; 25) min, respectively. The difference was statistically significant (P=0.01). T90 after glucose bolus in brain and subcutaneous tissue was 10 min (8.75; 15) and 15 min (13.75; 21.25), respectively. T90 after insulin bolus in brain and subcutaneous tissue was 10 min (10; 15) and 20 min (20; 27.5), respectively. To the contrary, with literature, our results showed earlier glucose level changes in brain in comparison with subcutaneous tissue after glucose and insulin boluses. Our results suggest that glucose dynamics is different within monitored tissues under rapid changing glucose level and we can expect similar behavior in humans. Improved knowledge about glucose distribution and dynamics is important for avoiding hypoglycemia., M. Žourek, P. Kyselová, D. Čechurová, Z. Rušavý., and Seznam literatury