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2. Chronic cigarette smoking alters circulating sex hormones and neuroactive steroids in premenopausal women
- Creator:
- Michaela Dušková, Kateřina Šimůnková, Hill, M., Velíková, M., Kubátová, J., Lyudmila Kantcheva, Hana Kazihnitková, Hruškovičová, H., Pospíšilová, H., Rácz, B., Salátová, M., Veronika Cirmanová, Eva Králíková, Luboslav Stárka, and Antonín Pařízek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, smoking, menstrual cycle, luteal phase, follicular phase, sex hormones, neuroactive steroids, 14, and 612
- Language:
- English
- Description:
- a1_Chronic smoking alters the circulating levels of sex hormones and possibly also the neuroactive steroids. However, the data available is limited. Therefore, a broad spectrum of free and conjugated steroids and related substances was quantified by GC-MS and RIA in premenopausal smokers and in age-matched (38.9±7.3 years of age) non-smokers in the follicular (FP) and luteal phases (LP) of menstrual cycle (10 non-smokers and 10 smokers, in the FP, and 10 non-smokers and 8 smokers in the LP). Smokers in both phases of the menstrual cycle showed higher levels of conjugated 17-hydroxypregnenolone, 5α-dihydroprogesterone, conjugated isopregnanolone, conjugated 5α-pregnane-3β,20α-diol, conjugated androstenediol, androstenedione, testosterone, free testosterone, conjugated 5α-androstane-3α/β,17β-diols, and higher free testosterone index. In the FP, the smokers exhibited higher levels of conjugated pregnenolone, progesterone, conjugated pregnanolone, lutropin, and a higher lutropin/follitropin ratio, but lower levels of cortisol, allopregnanolone, and pregnanolone. In the LP, the smokers exhibited higher levels of free and conjugated 20α-dihydropregnenolone, free and conjugated dehydroepiandrosterone, free androstenediol, 5α-dihydrotestosterone, free and conjugated androsterone, free and conjugated epiandrosterone, free and conjugated etiocholanolone, 7α/β-hydroxy-dehydroepiandrosterone isomers, and follitropin but lower levels of estradiol and sex hormone binding globulin (SHBG) and lower values of the lutropin/follitropin ratio. In conclusion, chronic cigarette smoking augments serum androgens and their 5α/β-reduced metabolites (including GABAergic substances) but suppresses the levels of estradiol in the LP and SHBG and may induce hyperandrogenism in female smokers., a2_The female smokers had pronouncedly increased serum progestogens but paradoxically suppressed levels of their GABA-ergic metabolites. Further investigation is needed concerning these effects., M. Dušková ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Comparison of total and salivary cortisol in a low-dose ACTH (synacthen) test: Influence of three-month oral contraceptives administration to healthy women
- Creator:
- Kateřina Šimůnková, Luboslav Stárka, Martin Hill, Lubomír Kříž, Richard Hampl, and Karel Vondra
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, endokrinologie, kortizol, antikoncepce, endocrinology, cortisol, contraception, low dose ACTH test, salivary cortisol, total serum cortisol, free cortisol, cortisol binding globulin, oral contraceptives, 14, and 612
- Language:
- English
- Description:
- The objective of this study was to evaluate the influence of low-dose combined oral contraception (COC) on basal and stimulated (1 μg ACTH test) levels of serum and salivary cortisol (F), cortisone and on basal serum cortisol binding globulin (CBG), adrenocorticotropic hormone (ACTH), dehydroepiadrosterone (DHEA) and calculated free cortisol in healthy young women. Three-month administration of COC resulted in 1) significant increase of basal (454.0±125.0 to 860.9±179.7 nmol/l) and ACTH-stimulated serum cortisol in 30th min (652.3±60.5 to 1374.1±240.6 nmol/l); 2) no significant change of basal (15.4±7.3 to 18.9±8.5 nmol/l) and ACTH-stimulated salivary cortisol at the 30th min (32.4±8.8 to 32.9±9.0 nmol/l); 3) no significant change of basal serum cortisone (38,8±7.68 to 45.2±24.2 nmol/l) and ACTH-stimulated cortisone at the 30th (34.8±10.9 to 47.0±35.7 nmol/l); 4) significant increase of basal ACTH (17.2±9.0 to 38.2±29.4 ng/l), CBG (991.0±161.0 to 2332.0±428.0 nmol/l), and 5) no significant change of basal DHEA (24.6±15.7 to 22.6±11.7 μmol/l) and calculated basal value for free cortisol (22.8±14.9 to 19.2±6.9nmol/l). In conclusions, higher basal and ACTH-stimulated serum cortisol were found after three-month administration of COC, while basal and stimulated salivary cortisol were not significantly affected. Therefore, salivary cortisol can be used for assessment of adrenal function in women regularly using COC., K. Šimůnková, L. Stárka, M. Hill, L. Kříž, R. Hampl, K. Vondra., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Effects of smoking cessation on hormonal levels in men
- Creator:
- Hruškovičová, H., Michaela Dušková, Kateřina Šimůnková, Hill, M., Pospíšilová, H., Rácz, B., Eva Králíková, Karel Vondra, and Luboslav Stárka
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, steroids, smoking cessation, prediction, body mass index, sex hormone-binding globulin, 14, and 612
- Language:
- English
- Description:
- Chronic smoking can cause imbalance in endocrine homeostasis and impairment of fertility in both sexes. The male reproductive system is more resilient, still the literature provides conflicting results about the influence of smoking on the steroid hormone levels. The data about smoking cessation are limited; there has not yet been a study primarily focused on changes in steroids levels. In our study, we analyzed levels of testosterone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS), cortisol and sex hormone-binding globulin (SHBG) in male smokers and during smoking cessation. Monitored analytes were determined by RIA. The free testosterone index was calculated. Basal samples of men successful and unsuccessful in smoking cessation did not differ and monitored hormones could hardly predict success of smoking cessation. After one year without smoking, a significant BMI increase and SHBG decrease in former smokers was observed. The decrease in total testosterone was non-significant. Changes in SHBG and testosterone did not correlate with BMI, presumably due to the direct effect of smoking cessation., H. Hruškovičová, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Evaluation of hepatic 11β-hydroxysteroid dehydrogenase activity by cortisone acetate test in young adults with diabetes mellitus type
- Creator:
- Kateřina Šimůnková, Richard Hampl, Hill, M., Lubomír Kříž, Jana Vrbíková, Hana Kvasničková, and Karel Vondra
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kortizol, diabetes mellitus, cortisol, cortisone, cortisone acetate test, peripheral metabolism of glucocorticoids, 14, and 612
- Language:
- English
- Description:
- Cortisone acetate test was performed in twelve young adult patients with diabetes mellitus type 1, after dexamethasone administration to suppress endogenous cortisol production. Previous screening revealed that all of the subjects had peak cortisol responses in the range from subnormal to normal, as determined by a low-dose Synacthen test. The aim was to find out whether these patients would exhibit different conversion of cortisone to cortisol by 11β-hydroxysteroid dehydrogenase. Using multifactorial ANOVA the following significant relationships were obtained between cortisol or cortisol/cortisone ratio measured during the test and other para meters examined a) before dexamethasone suppression and b) du ring the test: a) Cortisol at 120 th minute negatively correlated with daily insulin dose and positively with basal aldosterone. Cortisol/cortisone ratio at 60th, 120th, 180th, and 240th minute negatively correlated with basal aldosterone/plasma reni n activity ratio, urinary free cortisol/24 hours and positively with basal dehydroepindrosterone sulphate. b) Cortisol at 120th minute negatively correlated with suppressed basal serum glycemia; cortisol/cortisone ratio during the whole test negatively correlated with supressed basal ACTH. The examination of peripheral metabolism of cortisol using cortisone acetate test in patients with di abetes mellitus type 1 showed adaptive changes of 11β-hydroxysteroid dehydrogenace activity associated with altered cortisol tissue supply., K. Šimůnková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Higher levels of salivary α-amylase predict failure of cessation efforts in male smokers
- Creator:
- Michaela Dušková, Kateřina Šimůnková, Martin Hill, Hruškovičová, H., Petra Hoskovcová, Eva Králíková, and Luboslav Stárka
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, predikce, odvykání kouření, stres (fyziologie), prediction, smoking cessation, stress (physiology), salivary α-amylase, salivary cortisol, 14, and 612
- Language:
- English
- Description:
- The ability to predict the success or failure of smoking cessation efforts will be useful for clinical practice. Stress response is regulated by two primary neuroendocrine systems. Salivary cortisol has been used as a marker for the hypothalamuspituitary- adrenocortical axis and salivary α-amylase as a marker for the sympathetic adrenomedullary system. We studied 62 chronic smokers (34 women and 28 men with an average age of 45.2±12.9 years). The levels of salivary cortisol and salivary α-amylase were measured during the period of active smoking, and 6 weeks and 24 weeks after quitting. We analyzed the men separately from the women. The men who were unsuccessful in cessation showed significantly higher levels of salivary α-amylase over the entire course of the cessation attempt. Before stopping smoking, salivary cortisol levels were higher among the men who were unsuccessful in smoking cessation. After quitting, there were no differences between this group and the men who were successful in cessation. In women we found no differences between groups of successful and unsuccessful ex-smokers during cessation. In conclusions, increased levels of salivary α-amylase before and during smoking cessation may predict failure to quit in men. On the other hand, no advantage was found in predicting the failure to quit in women. The results of our study support previously described gender differences in smoking cessation., M. Dušková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Melatonin negatively correlates with C-peptide after food intake
- Creator:
- Luboslav Stárka, Michaela Dušková, Rácz, B., Kateřina Šimůnková, Martin Hill, and Radmila Kancheva
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, endokrinologie, melatonin, peptidy, příjem potravy, metabolismus sacharidů, biorytmy, endocrinology, peptids, ingestion, sacharide metabolism, biological rhythms, C-peptid, 14, and 612
- Language:
- English
- Description:
- Melatonin plays a key role in the circadian timing system. At present, many other functions of melatonin are known. Question remains whether changes in endogenous melatonin may be associated with food intake. Hence, the levels of melatonin, C-peptide and glucose were followed during a daily regimen (16 hours) including standardized food intake using commercial kits. The diurnal profiles of the hormones and serum glucose were evaluated using ANOVA with Period and Subject as independent factors. Pearson’s correlations and using a multiple stepwise backward regression model consisting of the time factor as a polynomial, and serum C-peptide and glucose assessed the correlations between melatonin and the remaining parameters. Our results showed a significant negative correlation between melatonin and C-peptide. The profile of melatonin was physiological, decreasing after wake-up, showing minor changes during the daytime and increasing in the evening. As documented, lesser alterations were indicated in the course of the melatonin daytime profile, which may reflect periodic food intake. Food intake is not the primary factor influencing the melatonin course. While previous studies have mostly considered the protective effect of melatonin in diabetic subjects, our study brought the results suggesting food intake as a factor contributing to daytime melatonin variation in humans. However, the physiological role of melatonin association with food intake in daytime remains in question and should be further investigated., L. Stárka, M. Dušková, B. Rácz, K. Šimůnková, M. Hill, R. Kancheva., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Response of cortisol metabolites in the insulin tolerance test and synacthen tests
- Creator:
- Kateřina Šimůnková, Michaela Dušková, Mikuláš Kosák, Michal Kršek, Václav Hána, Hill, M., Jandikova, H., Pospíšilová, H., Šrámková, M., Bifulco, E., and Luboslav Stárka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kortizol, cortisol, synacthen test, cortisone, insulin tolerance test, 14, and 612
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Salivary cortisol in low dose (1 μg) ACTH test in healthy women: comparison with serum cortisol
- Creator:
- Kateřina Šimůnková, Richard Hampl, Miroslav Hill, Jiří Doucha, Luboslav Stárka, and Karel Vondra
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, kortizol, physiology, cortisol, low dose ACTH test, salivary cortisol, total serum cortisol, transcortin, 14, and 612
- Language:
- English
- Description:
- To date, a single report has appeared on the use of salivary cortisol for adrenal function testing with a low dose ACTH, although 1 μg has become preferred as a more physiological stimulus than the commonly used 250 μg ACTH test. Our present study was aimed to obtain physiological data on changes of free salivary cortisol after 1 μg ACTH stimulation. This approach was compared with the common method based on the changes of total serum cortisol. Intravenous, low-dose ACTH test was performed in 15 healthy women (aged 22-40 years) with normal body weight, not using hormonal contraceptives, in the follicular phase of the menstrual cycle. Blood and saliva for determination of cortisol were collected before ACTH administration and 30 and 60 min after ACTH administration. Basal concentration of salivary cortisol (mean ± S.E.M., 15.9±1.96 nmol/l) increased after 1 μg ACTH to 29.1±2.01 nmol/l after 30 min, and to 27.4±2.15 nmol/l after 60 min. The differences between basal and stimulated values were highly significant (p<0.0001). The values of salivary cortisol displayed very little interindividual variability (p<0.04) in contrast to total serum cortisol values (p<0.0001) A comparison of areas under the curve (AUC) related to initial values indicated significantly higher AUC values for salivary cortisol than for total serum cortisol (1.89±0.88 vs. 1.22±0.19, p<0.01). Correlation analysis of serum and salivary cortisol levels showed a borderline relationship between basal levels (r=0.5183, p=0.0525); correlations after stimulation were not significant. Low-dose ACTH administration appeared as a sufficient stimulus for increasing salivary cortisol to a range considered as a normal adrenal functional reserve., K. Šimůnková, R. Hampl, M. Hill, J. Doucha, L. Stárka, K. Vondra., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Serum cortisol seems to be a more appropriate marker for adrenocortical reserve evaluation in ACTH test in comparison to salivary cortisol
- Creator:
- Mikuláš Kosák, Václav Hána, Hill, M., Kateřina Šimůnková, Zdeňka Lacinová, Michal Kršek, and Marek, J.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kortizol, cortisol, hypocorticalism, ACTH test, serum cortisol, salivary cortisol, 14, and 612
- Language:
- English
- Description:
- Salivary cortisol reflects the free fraction of serum cortisol. Monitoring salivary cortisol may be a promising alternative method for assessing serum cortisol in some clinical situations. We aimed to compare the reliability of salivary vs. serum cortisol during ACTH test. 84 subjects (mean age 63.2; 24-89 years; n=66 males) suspected for adrenocortical insufficiency underwent an ACTH test. Patients were divided based on peak serum cortisol into hypocortical group with cortisol <500 nmol/l and to reference group cortisol >500 nmol/l. Median serum cortisol levels in reference gr oup were 445, 766, and 902 nmol/l at 0, 30, and 60 minutes, respecti vely, and in hypocortical group were 256, 394, and 453 nmol/l. Median salivary cortisol levels were 19.02, 40.02, and 62.1 nmol/l in reference group, and 9.60, 14.08, and 13.28 nmol/l in hypoco rtical group. Obtained values showed good correlation between serum and salivary cortisol (p<0.0001). The percentage of explained variability R 2 (coefficient of determination for linear model) representing a measure of agreement betwee n experimental values and predictions for repeated measur es ANOVA, was significantly higher (p=0.021) for serum cortisol (R 2 =93.4 %) when compared to the salivary cortisol (R 2 =89.3 %). A stronger discriminating power of serum versus salivary cortisol suggests that it seems to be slightly, but statistically significantly more appropriate marker of adrenocortical reserve in ACTH test., M. Kosák ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public