This study aimed to examine the effect of dietary flavonoid isoquercitrin on ovarian granulosa cells using the immortalized human cell line HGL5. Cell viability, survival, apoptosis, release of steroid hormones 17β-estradiol and progesterone, and human transforming growth factor-β2 (TGF-β2) and TGF-β2 receptor as well as intracellular reactive oxygen species (ROS) generation were investigated after isoquercitrin treatment at the concentration range of 5-100 μg.ml-1 . It did not cause any significant change (p>0.05) in cell viability as studied by AlamarBlue assay in comparison to control. No significant change was observed (p>0.05) in the proportion of live, dead and apoptotic cells as revealed by apoptotic assay using flow cytometry. Similarly, the release of 17β-estradiol, progesterone, TGF-β2 and its receptor were not affected significantly (p>0.05) by isoquercitrin as detected by ELISA, in comparison to control. Except for the highest concentration of 100 μg.ml-1 , which led to oxidative stress, isoquercitrin exhibited antioxidative activity at lower concentration used in the study (5, 10, 25, and 50 μg.ml-1 ) by hampering the production of intracellular ROS, in comparison to control, as detected by chemiluminescence assay (p<0.05). Findings of the present study indicate an existence of the antioxidative pathway that involves inhibition of intracellular ROS generation by isoquercitrin in human ovarian granulosa cells., Adriana Kolesárová, Katarína Michalcová, Shubhadeep Roychoudhury, Simona Baldovská, Eva Tvrdá, Jaromír Vašíček, Peter Chrenek, Ľuboslav Sanisló, Vladimír Křen., and Obsahuje bibliografii
The aim of this study was to look for changes in the daily profile of steroid hormones after standardized food intake. Eight young women not taking contraceptives were followed from 5:30 a.m. till 9:30 p.m. before and 1 and 2 h after eating breakfast, snack, lunch, the second snack and dinner. The differences in steroid levels before and after meals were evaluated. As expected, glucose, C-peptide and ghrelin levels changed postprandially. The steroid hormones cortisol, progesterone, pregnenolone and dehydroepiandrosterone showed a decrease after main meals, whereas testosterone and dihydrotestosterone showed no significant dependence on food intake. Estrogen levels did not exhibit a significant nycthemeral rhythm, but estradiol decreased after main meals. In our study the known nycthemeral rhythm of LH, FSH, cortisol, progesterone and pregnenolone after food intake were confirmed, but significant changes after meals were also observed in the levels of cortisol, dehydroepiandrosterone, estradiol and SHBG., B. Rácz, M. Dušková, K. Vondra, M. Šrámková, M. Hill, L. Stárka., and Obsahuje bibliografii
The cyclical effects of hormones during the menstrual cycle (MC) are not just responsible for driving ovulation, but also have significant influence on dietary intake and appetite, as well as psychological and behavioral changes. The aim of our study was to describe changes and relationships between the MC and selected steroids, adipokines and food intake-related hormones. Twenty-seven women with regular menstrual cycles were included in the study, and their hormonal spectrum was measured in regular intervals starting from the first day of their cycle. Classical changes in gonadotropins, estrogens and progesterone during the menstrual cycle are accompanied by less striking but significant changes in 17-hydroxyprogesterone and testosterone. No significant changes show dehydroepiandrosterone and its 7-oxygenated metabolites. Adipokines show a tendency to increase during ovulation, while ghrelin and resistin decrease. There is also a remarkable association of sex hormone-binding globulin on the day of the cycle. Our results demonstrate that changes to adipokines during the menstrual cycle are not substantial, but nonetheless can play a role in the changes of food intake described in the literature. Precise descriptions of physiological changes in healthy women are important in helping us understand the significance of the changes accompanying various pathological states., M. Šrámková, M. Dušková, J. Vítků, J. Včelák, P. Matucha, O. Bradnová, J. de Cordeiro, L. Stárka., and Obsahuje bibliografii
Resistance to steroid hormones presents a serious problem with respect to their mass use in therapy. It may be caused genetically by mutation of genes involved in hormonal signaling, not only steroid receptors, but also other players in the signaling cascade as co-regulators and other nuclear factors, mediating the hormone-born signal. Another possibility is acquired resistance which may develop under long-term steroid treatment, of which a particular case is down regulation of the receptors. In the review recent knowledge is summarized on the mechanism of main steroid hormone action, pointing to already proven or potential sites causing steroid resistance. We have attempted to address following questions: 1) What does stay behind differences among patients as to their response to the (anti)steroid treatment? 2) Why do various tissues/cells respond differently to the same steroid hormone though they contain the same receptors? 3) Are such differences genetically dependent? The main attention was devoted to glucocorticoids as the most frequently used steroid therapeutics. Further, androgen insensitivity is discussed with a particular attention to acquired resistance to androgen deprivation therapy of prostate cancer. Finally the potential causes are outlined of breast and related cancer(s) resistance to antiestrogen therapy., R. Hampl, K. Vondra., and Obsahuje bibliografii
Isoflavones are a subgroup of phytoestrogens, natural plant substances with structure similar to 17-β-estradiol and capable of binding to estrogen receptors (ERs). Isoflavones possess higher affinity to ERβ than to ERα and may have a potency to activate both genomic and non-genomic estrogen signaling pathways. In addition, isoflavones interact with the metabolism of steroid hormones. Therefore, the actions of isoflavones are rather complex and may be related to large number of factors, which are not satisfactorily identified yet. Recently, isoflavones have come into focus of interest due to several reports about their positive effect on human health, in particular prevention of hormone-dependent cancers, cardiovascular diseases, osteoporosis, adverse menopausal manifestations and agerelated cognitive decline. Isoflavones may bring new insights into the mechanisms of physiological regulations and increase the possibilities of medical interventions., L. Pilšáková, I. Riečanský, F. Jagla., and Obsahuje bibliografii a bibliografické odkazy
The mood and behavior of individuals result from an orchestra of many factors. Among them steroids play an important role; however, only several common hormones have been investigated in this respect. It has been demonstrated that some steroid metabolites long considered merely the products of steroid hormone metabolism in fact possess considerable activity in the CNS. For this reason we studied the steroid metabolome including 50 analytes in 20 men with depression, 20 men with anxiety and 30 healthy controls. Significant differences were found not only between controls and men with either depression or anxiety, but also between men with depression and anxiety. Particularly striking were those steroids until now not generally associated with depression or anxiety, namely conjugated steroid forms, especially sulfates., M. Dušková, M. hill, M. Bičíková, M. Šrámková, D. Řípová, P. Mohr, L. Stárka., and Obsahuje bibliografii