Influence of the regulatory system mediated by adenosine A3 receptors on the functioning of erythropoiesis and thrombopoiesis was studied by means of evaluation of the numbers and attributes of peripheral blood erythrocytes and platelets, as well as of erythroid bone marrow progenitor cells in adenosine A3 receptor knock-out (Adora3tm1Jbsn/Adora3tm1Jbsn, A3AR(-/-)) mice and their wild-type C57BL/6 counterparts, both males and females. Minor but statistically significant disturbances in the properties of erythrocytes, namely in the parameters of mean erythrocyte volume and mean erythrocyte hemoglobin were observed in A3AR(-/-) mice. In addition, adenosine A3 receptor knock-out mice were found to exhibit an expressive, statistically significant decrease of their blood platelet count, amounting to 17 % and 21 % in males and females, respectively. This decrease in platelet levels was accompanied by a significant 17 % decline in the plateletcrit in both sexes. The obtained data can help to define therapeutic applications based on the principle of adenosine receptor signaling., M. Hofer, ... [et al.]., and Obsahuje seznam literatury
Escherichia coli (2x104 bacteria) of the non-pathogenic O86 strain or enteropathogenic O55 strain were administered into the pig amniotic cavity at 79 to 86 days of gestation for six or ten hours. Translocation of bacteria into fetal lungs was confirmed by cultivation as well as by light and electron microscopy. Infection caused an influx of macrophages that were immunostained in cryostat sections by monoclonal antibody recognizing calprotectin., I. Šplíchal, I. Trebichavský, A. Šplíchalová, L. Dítětová, M. Zahradníčková., and Obsahuje bibliografii
Clinical studies showed that GABAB receptor agonists improve symptoms in patients with gastroesophageal reflux disease. One proposed mechanism of this effect is direct inhibition of the gastroesophageal vagal tension mechanosensors by GABAB agonists leading to reduction of reflux. In addition to tension mechanosensors, the vagal nodose ganglion supplies the esophagus with nociceptive C-fibers that likely contribute to impairment of esophageal reflex regulation in diseases. We hypothesized that GABAB agonists inhibit mechanically-induced activation of vagal esophageal nodose C-fibers in baseline and/or in sensitized state induced by inflammatory mediators. Ex vivo extracellular recordings were made from the esophageal nodose C-fibers in the isolated vagally-innervated guinea pig esophagus. We found that the selective GABAB agonist baclofen (100- 300 μM) did not inhibit activation of esophageal nodose C-fibers evoked by esophageal distention (10-60 mmHg). The mechanical response of esophageal nodose C-fibers can be sensitized by different pathways including the stimulation of the histamine H1 receptor and the stimulation the adenosine A2A receptor. Baclofen failed to inhibit mechanical sensitization of esophageal nodose Cfibers induced by histamine (100 μM) or the selective adenosine A2A receptor agonist CGS21680 (3 nM). Our data suggest that the direct mechanical inhibition of nodose C-fibers in the esophagus is unlikely to contribute to beneficial effects of GABAB agonists in patients with esophageal diseases., M. Brozmanová, ... [et al.]., and Obsahuje seznam literatury
Strenuous exercise induces delayed-onset muscle damage including oxidative damage of cellular components. Oxidative stress to muscle cells impairs glucose uptake via disturbance of insulin signaling pathway. We investigated glucose uptake and insulin signaling in relation to oxidative protein modification in muscle after acute strenuous exercise. ICR mice were divided into sedentary and exercise groups. Mice in the exercise group performed downhill running exercise at 30 m/min for 30 min. At 24 hr after exercise, metabolic performance and insulin-signaling proteins in muscle tissues were examined. In whole body indirect calorimetry, carbohydrate utilization was decreased in the exercised mice along with reduction of the respiratory exchange ratio compared to the rested control mice. Insulin-stimulated uptake of 2-deoxy-[3 H]glucose in damaged muscle was decreased after acute exercise. Tyrosine phosphorylation of insulin receptor substrate (IRS)-1 and phosphatidyl-3-kinase/Akt signaling were impaired by exercise, leading to inhibition of the membrane translocation of glucose transporter 4. We also found that acute exercise caused 4-hydroxy-nonenal modification of IRS-1 along with elevation of oxidative stress in muscle tissue. Impairment of insulin-induced glucose uptake into damaged muscle after strenuous exercise would be related to disturbance of insulin signal transduction by oxidative modification of IRS-1., W. Aoi ... [et al.]., and Obsahuje seznam literatury
a1_We have investigated expression of skeletal calsequestrin (CSQ1) and fiber type composition in normal and regenerated fast and slow skeletal muscles and in the left heart ventricles of euthyroid (EU), hypothyroid (HY) and hyperthyroid (TH) adult inbred Lewis strain rats. The CSQ1 level was determined by SDS-PAGE followed by Western blot analysis. CSQ1 gene expression was assessed using reverse transcription and subsequent real time polymerase chain reaction. Muscle regeneration was achieved by intramuscular grafting of either soleus or extensor digitorum longus (EDL) from 3- to 4-week-old rats to either EDL or soleus muscle of 2-month-old rats. The fiber type composition was assessed by a stereological method applied to stained muscle cross sections. We found that the protein and mRNA levels for CSQ1 were highest in the EDL muscle, the relative CSQ1 protein levels in the soleus muscle were two times lower and the transcript levels more than 5 times lower compared to the EDL. In the left heart ventricle, protein isoform and CSQ1 transcript were also present, although at protein level, CSQ1 was hardly detectable. TH status increased and HY status decreased the expression of CSQ1 in the EDL, but its relative levels in the soleus and in the heart did not change. The regenerated soleus transplanted into EDL, as well as EDL transplanted into soleus exhibited protein and mRNA levels of CSQ1 corresponding to the host muscle and not to the graft source. TH status increased the percentages of the fastest 2X/D and 2B fibers at the expense of slow type 1 and fast 2A fibers in the EDL and that of fast 2A fibers in the soleus at the expense of slow type 1 fibers. HY status led to converse fiber type changes., a2_We suggest that the observed changes in CSQ1 levels in TH and HY compared to EU rats can be related to fiber type changes caused by alteration of the thyroid status rather than to the direct effect of thyroid hormones on CSQ1 gene expression., T. Soukup ... [et al.]., and Obsahuje seznam literatury
Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP/HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7), myristoleic (14:1n-5) and trans-palmitoleic acid (16:1n-7t). Negative correlation was found with baseline oleic acid (18:1n-9). Lower baseline monounsaturated fatty acids (14:1n-5, 16:1n-7 and trans 16:1n-7) in adipose tissue triglycerides predict better weight maintenance. Lower oleic acid predicts lower weight decrease. These findings suggest a specific role of monounsaturated fatty acids in weight management and as weight change predictors., M. Kunešová, ... [et al.]., and Obsahuje seznam literatury
This study evaluates bone mineral density (BMD) and trabecular bone score (TBS) in relationship with new markers of chronic kidney disease (CKD), fibroblast growth factor 23 (FGF23), and klotho. The patients in this cross-sectional study were divided as follows: group A -patients in stages G1-3; group B -patients in stages G4 - 5 according to KDIGO. Plasma levels of soluble klotho and FGF23 were determined by ELISA. Bone mineral density (BMD) and trabecular bone score (TBS) were measured. 74 patients with CKD (mean age 68.8 years) were included in the study. Higher levels of FGF23 were observed in group B (N=15) compared to group A (N=59; p=0.001) were observed. FGF23 was higher in group A compared to group B. Significant difference in TBS within the first 3 stages of CKD was observed (mean TBS in G1=1.375 vs. G2=1.340 vs. G3a=1.24; p<0.05) and negative correlation of FGF23 and TBS (R=-0.33; p=0.05) and positive correlation between klotho and TBS (R=0.419; p=0.04) was observed. This study confirmed that FGF23 and klotho are associated with TBS, but TBS reflects a decrease in kidney function only in the first 3 stages of CKD. Thus, FGF23 and klotho together with TBS are promising markers of early trabecular bone impairment in CKD., Zuzana Kužmová, Martin Kužma, Andrea Gažová, Magdaléna Kovářová, Peter Jackuliak, Zdenko Killinger, Ján Kyselovič, Juraj Payer., and Obsahuje bibliografii
Aluminofluoride complexes (AlFx) form spontaneously in aqueous solutions containing fluoride and traces of aluminum ions and appear to act as phosphate analogs. These complexes have become widely utilized in laboratory investigations of various guanine nucleotide-binding proteins. Reflecting on many laboratory studies, a new mechanism of fluoride and aluminum action on the cellular level is being suggested. The long-term synergistic effects of these ions in living environment and their hidden danger for human health are not yet fully recognized., A. Strunecká, O. Strunecký, J. Patočka., and Obsahuje bibliografii
The review shows the significance of blood pressure regulation studies conducted during several decades at the Department of Physiology, Faculty of Medicine, Masaryk University, Brno. Continuous non-invasive blood pressure measurement was first introduced and patented here and, with the obtained data, the first spectral analysis of blood pressure was performed. This method was used in many different physiological studies on the relationship of blood pressure regulation to circulatory parameters, breathing, and baroreflex sensitivity. The article deals with studies on risk stratification of sudden cardiac death according to decreased baroreflex sensitivity, 24-hour heart rate variability, the amount of extrasystoles and late potentials. Importance of the new method of determination of one summation risk index is described here. A summary of the new conception of the relationship between low baroreflex sensitivity and hypertension is presented. Here, not only pathological changes of the vessel wall but also increased sympathetic activity and genetic predisposition play a role. Importance of studies conducted in young adults is highlighted, as inherited BRS decrease contributes to earlier blood pressure increase in the young. This research is highly topical, since prevention of hypertension in childhood is possible. Recent studies are dedicated to blood pressure regulation in young diabetics., Z. Nováková., and Obsahuje seznam literatury