Increased homocysteine levels in serum are typical features of neurodegenerative brain diseases including hydrocephalus. The most frequent therapeutic approach consists of the insertion of a shunt, connecting the brain ventricles to an alternative drainage site. To decide whether the patient should undergo this, the lumbar drainage test is usually carried out to distinguish patients who can benefit from the shunt insertion. In searching for other potential biochemical markers for shunt indication we determined homocysteine levels in CSF during the lumbar drainage test. Homocysteine in CSF was measured during the 5-day lumbar drainage test in 27 patients with normal-pressure hydrocephalus (NPH) and in 25 patients with excluded hydrocephalus. A novelized gas chromatography method with flame ionization detection (GC-FID) was developed and evaluated. During the first two days of lumbar drainage, the levels of CSF homocysteine in NPH patients were significantly higher compared to the controls, while on the fifth day, the homocysteine levels in patients with hydrocephalus reached the level of controls. Determination of CSF homocysteine in patients with confirmed or suspected hydrocephalus may serve as an independent marker for deciding on their further treatment strategy., L. Sosvorová, J. Bešťák, M. Bičíková, M. Mohapl, M. Hill, J. Kubárová, R. Hampl., and Obsahuje bibliografii
The general population is potentially exposed to many chemicals that can affect the endocrine system. These substances are called endocrine disruptors (EDs), and among them bisphenol A (BPA) is one of the most widely used and well studied. Nonetheless, there are still no data on simultaneous measurements of various EDs along with steroids directly in the seminal fluid, where deleterious effects of EDs on spermatogenesis and steroidogenesis are assumed. We determined levels of BPA and 3 estrogens using LC-MS/MS in the plasma and seminal plasma of 174 men with different degrees of infertility. These men were divided according their spermiogram values into 4 groups: (1) healthy men, and (2) slightly, (3) moderate, and (4) severely infertile men. Estradiol levels differed across the groups and body fluids. Slightly infertile men have significantly higher BPA plasma and seminal plasma levels in comparison with healthy men (p<0.05 and p<0.01, respectively). Furthermore, seminal BPA, but not plasma BPA, was negatively associated with sperm concentration and total sperm count (-0.27; p<0.001 and -0.24; p<0.01, respectively). These findings point to the importance of seminal plasma in BPA research. Overall, a disruption of estrogen metabolism was observed together with a weak but significant impact of BPA on sperm count and concentration., J. Vitku, L. Sosvorova, T. Chlupacova, R. Hampl, M. Hill, V. Sobotka, J. Heracek, M. Bicikova, L. Starka., and Obsahuje bibliografii
Hormones exert many actions in the brain. Their access and effects in the brain are regulated by the blood-brain barrier (BBB). Hormones as other substances may enter the brain and vice versa either by paracellular way requiring breaching tight junctions stitching the endothelial cells composing the BBB, or by passage through the cells (transcellular way). Hormones influence both ways through their receptors, both membrane and intracellular, present on/in the BBB. In the review the main examples are outlined how hormones influence the expression and function of proteins forming the tight junctions, as well as how they regulate expression and function of major protein transporters mediating transport of various substances including hormone themselves., R. Hampl, M. Bičíková, L. Sosvorová., and Obsahuje bibliografii
Resistance to vitamin D has been known for decades as vitamin D resistant rickets, caused by mutations of the gene encoding for vitamin D receptor (VDR). Findings of extra-skeletal effects of vitamin D and learning of the molecular mechanisms used by its biologically active metabolite calcitriol revealed other ways leading to its impaired sensitivity. Calcitriol takes advantage of both genomic and non-genomic mechanisms through its binding to vitamin D receptor, located not only in the cell nuclei but also in a perinuclear space. On the genomic level the complex of calcitriol bound to VDR binds to the DNA responsive elements of the controlled gene in concert with another nuclear receptor, retinoid X receptor, and expression of the VDR itself is controlled by its own ligand. These elements were found not only in the promotor region, but are scattered over the gene DNA. The gene expression includes a number of nuclear transcription factors which interact with the responsive elements and with each other and learning how they operate would further contribute to revealing causes of the impaired vitamin D sensitivity. Finally, the examples of major disorders are provided, associated with impairment of the vitamin D function and its receptor., L. Máčová, M. Bičíková, R. Hampl., and Obsahuje bibliografii
The levels of four pregnanolone isomers and their polar conjugates and pregnenolone sulfate were measured in the plasma of 13 and 7 women at delivery with subarachnoidal and epidural analgesia, respectively, and in corresponding samples of umbilical plasma using a simple quadrupole GC/MS system with electron impact ionization (pregnenolone isomers), RIA following HPLC separation (pregnenolone) and specific RIA (pregnanolone sulfate). The concentration of epipregnanolone (3b-hydroxy-5b-pregnan-20-one) in both maternal and umbilical plasma was much lower than that of other pregnanolone isomers. The levels of 3b-hydroxy-pregnanolone isomers were significantly higher in the umbilical plasma than in the maternal, while the differences in 3a-hydroxy-isomers were insignificant. The differences in conjugates were insignificant with the exception of allopregnanolone, the levels of which were lower in umbilical plasma. In all the pregnanolone isomers, a significantly lower conjugated/unconjugated steroid ratio was found in the umbilical plasma than in the maternal plasma. In addition, time profiles of the steroids were measured around parturition and in the postpartum period in the maternal serum. Similarly, the levels of polar conjugates of all pregnanolone isomers were followed during parturition. Changes in concentrations of free steroids exhibited a similar pattern, with a fall primarily within the first hour after delivery. The decrease in conjugated steroids was shifted to the interval within the first hour and first day after delivery, and the changes were more pronounced. The time profiles of the conjugated/free steroid ratio exhibited a significant decrease within the first hour and the first day after delivery in all of the isomers investigated. A decrease was also observed in the ratio of 3a/3b- isomers and 5a/5b- isomers around parturition.The possible physiological consequences of the findings are indicated., J. Klak, M. Hill, A. Pařízek, H. Havlíková, M. Bičíková, R. Hampl T. Fait, J. Šulcová V. Pouzar, R. Kancheva, L. Stárka., and Obsahuje bibliografii
Steroid sulfatase (EC 3.1.6.2) is an important enzyme involved in steroid hormone metabolism. It catalyzes the hydrolysis of steroid sulfates into their unconjugated forms. This action rapidly changes their physiological and biochemical properties, especially in brain and neural tissue. As a result, any imbalance in steroid sulfatase activity may remarkably influence physiological levels of active steroid hormones with serious consequences. Despite that the structure of the enzyme has been completely resolved there is still not enough information about the regulation of its expression and action in various tissues. In the past few years research into the enzyme prope ties and regulations has been strongly driven by the discovery of its putative role in the indirect stimulation of the growth of hormone-dependent tumors of the breast and prostate., L. Kříž, M. Bičíková, R. Hampl., and Obsahuje bibliografii a bibliografické odkazy
Normal pressure hydrocephalus (NPH) is one of a few treatable conditions of cognitive decline affecting predominately elderly people. Treatment, commonly based on the ventriculoperitoneal shunt insertion, leads to a partial or complete correction of patient's state, although its effect does not unfortunately always last. The aim of our study was to observe the changes of homocysteine and selected steroids and neurosteroids and follow-up the patients with respect to the duration of the NPH-related dementia improvement. The cerebrospinal fluid and plasma levels of cortisol, cortisone, dehydroepiandrosterone (DHEA), 7α-hydroxy-DHEA, 7β-hydroxy-DHEA, 7-oxo-DHEA, 16α-hydroxy-DHEA (all LC-MS/MS), DHEA-sulphate (DHEAS) (radioimmunoassay) and homocysteine (gas chromatography) were determined in NPH-diagnosed subjects before, during and 6, 12 and 24 months after shunt insertion. The cognitive functions ameliorated after shunt insertion and remain improved within 2 years. Changes in cerebrospinal fluid DHEAS, DHEA and its ratio, cortisone/cortisol and 16α-hydroxy-DHEA and plasma DHEAS, 7β-hydroxy-DHEA, cortisone/cortisol and homocysteine were found. Mentioned changes may contribute to the clarification of NPH pathogenesis. Altered neurosteroids levels are possible indicators to be utilized in the follow-up of NPH subjects. Moreover, plasma homocysteine may serve as an early indicator of NPH-related dementia., L. Sosvorova, M. Mohapl, M. Hill, L. Starka, M. Bicikova, J. Vitku, R. Kanceva, J. Bestak, R. Hampl., and Obsahuje bibliografii