The local concentration of glucocorticoids is intensively regulated by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD 1). Human 11β-HSD 1 also reversibly catalyzes the inter-conversion of 7α-hydroxy- and 7β-hydroxy-dehydroepiandrosterone (DHEA) into 7-oxo-DHEA. The cohort of 282 obese adolescents, 154 girls (median age 15.31 years, range 14.17-16.68 years) and 128 boys (median age 14.95 years, range 13.87-16.16 years), BMI (Body Mass Index) >90th percentile was examined. In samples collected before and after one month of reductive diet therapy, circulating levels of steroids were analyzed by liquid chromatography-tandem mass spectrometry and radioimmunoassay methods. The model of the treatment efficacy prediction was calculated. A significant reduction in circulating levels of cortisone, E2 and increased levels of 7β-hydroxy-DHEA after the reductive treatment was observed. Levels of cortisol, DHEA, DHT sustained without any significant change. The predictive Orthogonal Projections to Latent Structures (OPLS) model explained 20.1 % of variability of BMI, z-score change by the basal levels of 7α-hydroxy-DHEA, DHEA, cortisol and E2 as the strongest predictors. Reduced levels of circulating cortisone and reduced ratios of oxygenated/reduced metabolites reflect increased reductase activity of 11β-HSD 1 with reduced BMI, z-score. We hypothesize whether these changes can be attributed to the altered activity of 11β-HSD 1 in the liver., L. Máčová, L. Sosvorová, J. Vítků, M. Bičíková, M. Hill, H. Zamrazilová, B. Sedláčková, L. Stárka /., and Obsahuje bibliografii
Steroids are important marker s in pregnancy. Although estimating their levels separately in umbilical arterial (UA) and venous blood (UV) enable more precise insights into the functioning fetoplacental unit compared to using mixed umbilical blood (UM), selective aspiration of UA and UV is technically more demanding than collecting UM. We measured the levels of 67 unconjugated steroids and steroid polar conjugates in UA and UV using GC-MS in 80 women giving birth within weeks 28 to 42 of gestation. The samples were sorted into three groups: women entering labor within weeks 28- 32 (group A, n=19), weeks 33-37 (group B, n=19), and weeks 38-42 (group C, n=42) of gestation, respectively. The preterm labo rs were due to pathologies unrelated to steroid status. Most unconjugated steroids exhibited pronounced arteriovenous differences (AVD). The AVD were less distinct in more stable steroid conjugates. Most steroids positively correlate with gestational age, but unconjugated 5 β -reduced pregnanes show negative correlations, as do testosterone and androstenediol, substrates for the placental synthesis of estrogens. Tight correlations be tween steroids in UA and UV indicate that steroid measurements in UA, UV and UM can be accurately derived from each other, which is important for the diagnostics of steroid related diseases in newborns., A. Pašková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
It has been reported that the major function of the sterol regulatory element binding protein 2 (SREBP-2) is to activate preferentially cholesterol biosynthesis in liver and adipose tissue rather than fatty acid synthesis. In the current study, we analyzed the effects of overexpression of human dominantpositive SREBP-2 transgene under control of PEPCK promoter in the spontaneously hypertensive rat (SHR) on lipid and glucose metabolism. Transgenic overexpression of SREBP-2 was associated with significantly higher hepatic triglycerides (20.4±0.9 vs. 17.0±0.05 μmol/g, P<0.05) but not cholesterol (10.6±0.4 vs. 10.9±0.4 μmol/g) and decreased relative weight of epididymal fat pad (0.73±0.03 vs. 0.830.03, P<0.05). In addition, muscle triglyceride (15.8±3.7 vs. 8.5±1.2 μmol/g, P<0.001) and cholesterol (3.6±0.5 vs. 2.1±0.1 μmol/g, P<0.05) concentrations were significantly increased in transgenic rats when compared to SHR controls. Ectopic fat accumulation was associated with significantly increased serum glucose levels (6.4±0.1 vs. 5.9±0.1 mmol/l, P<0.005) and reduced insulin levels (1.78±0.33 vs. 2.73±0.37 nmol/l, P<0.05) in transgenic rats. These results provide evidence for important role of SREBP-2 in regulation of lipid and glucose metabolism., V. Landa, V. Zídek, P. Mlejnek, M. Šimáková, J. Šilhavý, J. Trnovská, L. Kazdová, M. Pravenec., and Obsahuje bibliografii
The STESYS2 software is a new version of the IBM PC software supporting interactive stereological measurements. In comparison with the previous STESYS, it is enhanced by a number of useful options, e.g. on-line image input via a TV camera coupled with a microscope operating under MS Windows OS. The main advantage, when compared with other such software packages, is the design of the STESYS2 as a module of the freeware image processing system Image Tool which provides a user-friendly environment including a number of image processing and preprocessing routines. Capabilities of the STESYS2 are illustrated by a practical example: estimation of the surface area of capillaries in the terminal villi of human placenta by the Sandau spatial grid method., Z. Tomori, L. Matis, P. Karen, L. Kubínová, I. Krekule., and Obsahuje bibliografii
Quaternary ammonium salts, besides having an inhibitory effect which was studied by Králová eí al. (1992), exhibited at low concentrations a stimulating effect upon the oxygen evolution rate in spinách chloroplasts. The stimulation is caused by changes in arrangement of thylakoid membranes due to a detergent-like effect of the compoimds.
The effects of 5 pmols of adipokinetic hormone (Lom-AKH-I) on both the locomotion and mobilization of lipids were studied in 10-day-old diapausing adult females of the short-winged (brachypterous) morph of Pyrrhocoris apterus (L.). The results revealed that AKH stimulation of locomotion in this bug is wing-morph independent. The stimulatory effect of AKH on locomotion was shown to be positively correlated with its effect on lipid mobilization., Radomír Socha, Dalibor Kodrík, Rostislav Zemek, and Lit