Determination of response of cortisol and its metabolites to different stimuli may be important for adrenal gland disorders. To date, only one metabolite, cortisone, has been followed in stimulation tests of the adrenal gland. We aimed to describe a response of cortisol metabolites to the standard short Synacthen test (HDST), insulin tolerance test (ITT), low dose Synacthen test (LDST) and medium dose Synacthen test (MDST). Sixty healthy subjects were investigated: 30 men and 30 women. Plasma for measurements of cortisol and its metabolites was obtained before and 30th and 60th min after Synacthen and insulin administration. The cut-off 500 nmol/l of cortisol was reached after stimulation in all of tests, the maximal stimulation level was reached in 60th min in all of the tests except for LDST. The response of cortisol and its metabolites at 30th and 60th min strongly correlated in all of the tests except for LDST. Cortisol and its metabolites increased after stimulation; in contrast, cortisone and its metabolites decreased. We showed that the response of the cortisol metabolites during the Synacthen tests and ITT well correlated, and the MDST showed similar response compared to HDST. The decrease in cortisone metabolites may correspond to the regeneration of cortisol from cortisone in response to stimulation test., K. Simunkova, M. Duskova, M. Kosak, M. Krsek, V. Hana, M. Hill, H. Jandikova, H. Pospisilova, M. Sramkova, E. Bifulco, L. Starka., and Obsahuje bibliografii
We investigated the effects of repeated hyperthermic bouts on the heat shock response of heat s hock protein ( HSP ) 72 in skeletal muscle. Rats were assigned to control and hyperthermia groups which were exposed to heated water at 42 °C. The hyperthermia group was further divided into sub -groups: a single bout (H30) or four bouts of hyperthermia for 30 min (H30x4). There was an increase in HSP72 protein content of the H30 groups in both extensor digitorum longus (EDL) and soleus muscles. Moreover, HSP72 protein expression in H30x4 group was significantly higher than in H30 group in both EDL and soleus muscles. The HSP72 mRNA was markedly increased from control levels in the H30 and H30x4 group in both types of muscles . However, HSP72 mRNA of the H30x4 group was lower than that of the H30 group in soleus muscles. Heat shock response of HSP72 is activate d even after repeated bouts of hyperthermia, with a differential regulation between muscle types., J. Lee, K. Himori, D. Tatebayashi, M. Abe, T. Yamada., and Obsahuje bibliografii
Conventional radiotherapy with X- and γ-rays is one of the common and effective treatments of cancer. High energy hadrons, i.e., charged particles like protons and 12C ions, due to their specific physics and radiobiological advantages are increasingly used. In this study, effectiveness of different radiation types is evaluated on the radio-resistant human HTB140 melanoma cells. The cells were irradiated with γ-rays, the 62 MeV protons at the Bragg peak and in the middle of the spread-out Bragg peak (SOBP), as well as with the 62 MeV/u 12 C ions. The doses ranged from 2 to 24 Gy. Cell survival and proliferation were assessed 7 days after irradiation, whereas apoptosis was evaluated after 48 h. The acquired results confirmed the high radio-resistance of cells, showing better effectiveness of protons than γ-rays. The best efficiency was obtained with 12C ions due to higher linear energy transfer. All analyzed radiation qualities reduced cell proliferation. The highest proliferation was detected for 12C ions because of their large killing capacity followed by small induction of reparable lesions. This enabled unharmed cells to preserve proliferative activity. Irradiations with protons and 12C ions revealed similar moderate pro-apoptotic ability that is in agreement with the level of cellular radio-resistance., A. Ristić-Fira ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
This study aimed to compare the effects of three different resistance exercise models on the quadriceps muscle crosssectional area, as well as on mTOR phosphorylation and other pivotal molecules involved in the upstream regulation of mTOR. Twenty-four male Wistar rats were divided into untrained (control), endurance resistance training, strength resistance training, and hypertrophy resistance training (HRT) groups (n=6). After 12 weeks of training, the red portion of the quadriceps was removed for histological and Western blot analyses. The results showed that the quadriceps weight and cross-sectional areas in the exercised groups were higher than those of the untrained rats. However, the HRT group presented better results than the other two experimental groups. This same pattern was observed for mTOR phosphorylation and for the most pivotal molecules involved in the upstream control of mTOR (increase of PKB, 14-3-3, ERK, p38 MAPK, and 4E-BP1 phosphorylation, and reduction of tuberin, sestrin 2, REDD1, and phospho AMPK). In summary, our study showed that HRT leads to high levels of mTOR phosphorylation as well as of other proteins involved in the upstream regulation of mTOR., T. F. Luciano, S. O. Marques, B. L. Pieri, D. R. de Souza, L. V. Araújo, R. T. Nesi, D. L. Scheffer, V. H. Comin, R. A. Pinho, A. P. Muller, C. T. de Souza., and Obsahuje bibliografii
We studied the psychophysiology of soluble intercellular adhesion molecule-1 (sICAM-1) in 25 apparently healthy middle-aged men who underwent an acute psychosocial stressor three times with one week apart. Measures of the biological stress response were obtained at week one and three. The magnitude of the sICAM-1 stress response showed no habituation between individual visits. At week one, cognitive stress appraisal independently predicted integrated sICAM-1 area under the curve (AUC) between rest, immediately post-stress, and 45 min and 105 min post-stress (β=0.67, p=0.012, ΔR2=0.41). Diastolic blood pressure AUC (β=-0.45, p=0.048, ΔR2=0.21) and heart rate AUC (β=0.44, p=0.055, ΔR2=0.21) were independent predictors of sICAM-1 AUC at week three. Adjustment for hemoconcentration yielded a decrease in sICAM-1 levels from rest to post-stress (p<0.001). Stress responsiveness of plasma sICAM-1 was predicted by stress perception and hemodynamic reactivity and affected by stress-hemoconcentration but unrelated to cortisol reactivity and not readily adapting to repeated stress., R. von Känel, D. Preckel, B. M. Kudielka, J. E. Fischer., and Obsahuje bibliografii a bibliografické odkazy
We present the current state of complex circulatory dynamics model development based on Guyt on’s famous diagram. The aim is to provide an open-source model that will allow the simulation of a number of pathological conditions on a virtual patient including cardiac, respiratory, and kidney failure. The model will also simulate the therapeutic influence of various drugs, infusions of electrolytes, blood transfusion, etc. As a current result of implementation, we describe a co re model of human physiology targeting the systemic circulation, arterial pressure and body fluid regulation, including short- and long-term regulations. The model can be used for educational purposes and general reflection on physiological regulation in path ogenesis of various diseases., J. Kofránek, J. Rusz., and Obsahuje bibliografii
Resveratrol is a polyphenol found in different plant species and having numerous health-promoting properties in animals and humans. However, its protective action against deleterious effects of ethanol is poo rly elucidated. In the present study, the influence of resveratrol (10 mg/kg/day) on some hormones and metabolic parameters was determined in rats ingesting 10 % ethanol solution for two weeks. Blood levels of insulin, glucagon and adiponectin were affecte d by ethanol, however, resveratrol partially ameliorated these changes. Moreover, in ethanol drinking rats, liver lipid accumulation was increased, whereas resveratrol was capable of reducing liver lipid content, probably due to decrease in fatty acid synt hesis. Resveratrol decreased also blood levels of triglycerides and free fatty acids and reduced γ-glutamyl transferase activity in animals ingesting ethanol. These results show that resveratrol, already at low dose, alleviates hormonal and metabolic changes induced by ethanol in the rat and may be useful in preventing and treating some consequences o f alcohol consumption., K. Szkudelska, M. Deniziak, P. Roś, K. Gwóźdź, T. Szkudelski., and Obsahuje bibliografii
Neonatal exposure to hyperoxia alters lung development in mice. We tested if retinoic acid (RA) treatment is capable to affect lung development after hyperoxic injury and to maintain structural integrity of lung. The gene of vascular endothelial growth factor A (VEGF-A) is one of the RA-responsive genes. Newborn BALB/c mice were exposed to room air, 40 % or 80 % hyperoxia for 7 days. One half of animals in each group received 500 mg/kg retinoic acid from day 3 to day 7 of the experiment. At the end of experiment we assessed body weight (BW), lung wet weight (LW), the wet-to-dry lung weight ratio (W/D) and the expression of mRNA for VEGF-A and G3PDH genes. On day 7 the hyperoxia-exposed sham-treated mice (group 80) weighed 20 % less than the room air-exposed group, whereas the 80 % hyperoxic group treated with RA weighed only 13 % less than the normoxic group. W/D values in 80 and 80A groups did not differ, although they both differed from the control group and from 40 groups. There was a significant difference between 40 and 40A groups, but the control group was different from 40 group but not from 40A groups. The 80 and 80A groups had mRNA VEGF-A expression lowered to 64 % and 41 % of the control group. RA treatment of normoxic and mild hyperoxic groups increased mRNA VEGF-A expression by about 50 %. We conclude that the retinoic acid treatment of newborn BALB/c mice exposed for 7 days to 80 % hyperoxia reduced the growth retardation in the 80 % hyperoxic group, reduced the W/D ratio in the 40 % but not in the 80 % hyperoxic group. Higher VEGF-A mRNA expression in the 80 % hyperoxic group treated with RA was not significant compared to the 80 % hyperoxic group., M. Zimová-Herknerová, J. Mysliveček, P. Potměšil., and Obsahuje bibliografii a bibliografické odkazy
The concept of vena contracta space reduction in tricuspid valve position was tested in an animal model. Feasibility of specific artificial obturator body (REMOT) fixed to the right ventricular apex and interacting with tricuspid valve leaflets was evaluated in three different animal studies. Catheter-based technique was used in three series of experiment in 7 sheep. First acute study was designed for evaluation if the screwing mode of guide wire anchoring to the right ventricular apex is feasible for the whole REMOT body fixing. Longer study was aimed to evaluate stability of the REMOT body in desired position when fixing the screwing wire on its both ends (to the right ventricular apex and to the skin in the neck area). X-ray methods and various morphological methods were used. The third acute study was intended to the REMOT body deployment without any fixing wire. In all of 7 sheep the REMOT was successfully inserted into the right heart cavities and then fixed to the ri ght ventricular apex area. When the REMOT was left in situ more than 6 months it was stable, induced adhesion to the tricuspid valve leaflet and was associated with a specific cell invasion. Releasing of the REMOT from the guiding tools was also successfully verified. Deployment of the obturator body in the aim to reduce the tricuspid valve orifice is feasible and well tolerated in the short and longer term animal model. Specific cell colonization including neovascularization of the obturator body was observed., J. Sochman ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The Prague Hereditary Hypercholesterolemic (PHHC) rat is a model of hypercholesterolemia. In previous experiments, it was found to be completely resistant to the development of atherosclerosis. It was assumed that the reverse transport of cholesterol (RCT) might be the reason for this resistance. In this study, RCT was measured in vivo by cholesterol efflux from macrophages to plasma, using previously established methods for RCT in mice (Rader 2003), optimized for measurements in rats. Primary cell culture of macrophages was labeled with 14Ccholesterol and then injected intraperitoneally into rats. Plasma and feces were collected at 24 and 48 h. The plasma 14Ccholesterol levels at both 24 and 48 h were significantly higher in male PHHC rats compared to control Wistar rats. The PHHC rats excreted less 14C-cholesterol in feces in 24 and 48 h compared to Wistar rats. The largest pool of 14C-cholesterol was found in the adipose tissue of PHHC rats and in contrast lower levels of 14Ccholesterol were measured in the liver and muscle tissues of PHHC rats compared with Wistar rats. Increasing release of 14Ccholesterol efflux from macrophages demonstrates accelerated RTC and leads to prevention of atherogenesis in PHHC rats., M. Schmiedtova, M. Heczkova, J. Kovar, I. Kralova Lesna, R. Poledne., and Obsahuje bibliografii