• MeSH
• cirkadiánní rytmus - signální peptidy a proteiny MeSH
• kritický stav * MeSH
• lidé MeSH
• melatonin * analýza   krev   MeSH
• prospektivní studie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• zprávy MeSH

OBJECTIVE: To evaluate changes in the expression of clock genes and melatonin levels in patients with idiopathic REM sleep behavior disorder (RBD) as a potential early stage of synucleinopathies. METHODS: We assessed the rhythmicity of circadian clock genes using real time-quantitative polymerase chain reaction and 24-h blood melatonin profiles using radio-immunoassay in 10 RBD patients and nine age-matched controls. RESULTS: The RBD patients did not show circadian rhythmicity for clock genes Per2, Bmal1, and Nr1d1 but the rhythmicity of Per 1 remained, and the amplitude of Per3 was diminished. The 24-h melatonin rhythm did not differ between RBD patients and healthy control subjects. Melatonin profile in RBD patients was delayed by 2 h compared to controls, the habitual sleep phases were phase delayed by about 1 h, however no phase shift occurred in any of the clock genes studied. The control group had stable acrophases of melatonin rhythms of approximately 5 h whereas the RBD patients had a more dispersed range over 11 h. CONCLUSIONS: Our results suggest that RBD could be associated with altered expression of clock genes and delayed melatonin secretion. Thus, we argue that circadian system dysregulation could play a role in RBD.

• MeSH
• cirkadiánní proteiny Period genetika   MeSH
• cirkadiánní rytmus genetika   MeSH
• exprese genu * MeSH
• jaderné receptory - podrodina 1, skupina D, člen 1 genetika   MeSH
• lidé MeSH
• melatonin krev   metabolismus   MeSH
• polysomnografie MeSH
• porucha chování v REM spánku genetika   MeSH
• proteiny CLOCK genetika   MeSH
• průzkumy a dotazníky MeSH
• senioři MeSH
• stadia spánku genetika   MeSH
• transkripční faktory ARNTL genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder with a complex pathogenesis and a common occurrence of comorbid diseases such as depression. It is accepted that the presence of the ε4 allele of the gene that encodes apolipoprotein E (APOE) is the strongest genetic risk factor for the development of sporadic AD. Melatonin, cortisol, homocysteine, and prolactin are presumed to be risk factors or biomarkers for stress- and age-related disorders. OBJECTIVE: The interplay between the APOE genotype and plasma biomarkers was examined in patients with AD presenting with or without depression to contribute to understanding the interdependence of various molecular mechanisms in the pathophysiology of AD. METHOD: The APOE genotype and morning plasma melatonin, cortisol, homocysteine, and prolactin concentrations were measured in 85 patients with AD and 44 elderly controls. RESULTS: A significant association between AD and the allele (ε4) or genotype (ε3/ε4 or ε4/ε4) frequencies of APOE was confirmed. Plasma homocysteine and cortisol levels were significantly increased in patients with AD compared to those in controls, independent of the presence of comorbid depressive symptoms or the severity of dementia. Significantly lower plasma melatonin concentration was found in patients with AD but not in controls, who were noncarriers of the APOE ε4 allele, regardless of the presence of depression or the severity of dementia in AD. CONCLUSION: Our findings indicate the existence of a little-known specific APOE-mediated mechanism that increases the plasma melatonin level in a subgroup of patients with AD who are carriers of the APOE ε4 allele.

• MeSH
• Alzheimerova nemoc krev   genetika   MeSH
• apolipoproteiny E genetika   MeSH
• biologické markery krev   MeSH
• genotyp MeSH
• homocystein krev   MeSH
• hydrokortison krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• melatonin krev   MeSH
• prolaktin krev   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Light is an important environmental factor that controls the regulation of physiological functions of organisms. Melatonin is considered as one of the major hormones that play an important role in protecting body from many harmful effects and acts as a powerful anti-oxidant source to controlling the levels of antioxidant enzymes within the body. The main objectives of this work were to study the effect of 1) photoperiod changes and 2) exogenous melatonin hormone treatment on the sperm properties, body and testis weight, embryo characteristics, and concentration level of melatonin and testosterone in treated rat serum. This study has been conducted using thirty-six male rats and one hundred and twenty female rats. Animals were divided into six groups, each group containing six males and twenty female rats. Our results showed a significant influence of photoperiod changes on the melatonin and testosterone hormones concentration in rats serum, body weight only, while the other characteristics not affected. As for the effect of melatonin it has been found that the movement of sperm in GIII and IV, as well as embryos absorbed and newborns weight traits has been significantly affected, while the rest of the properties were not significantly affected by melatonin treatment.

• MeSH
• fotoperioda * MeSH
• krysa rodu rattus MeSH
• melatonin krev   farmakologie   MeSH
• novorozená zvířata MeSH
• potkani Wistar MeSH
• rozmnožování účinky léků   fyziologie   MeSH
• spermie účinky léků   metabolismus   MeSH
• světlo * MeSH
• těhotenství MeSH
• testis účinky léků   metabolismus   MeSH
• testosteron krev   MeSH
• tma * MeSH
• velikost orgánu účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

A pineal cyst is a benign affection of the human pineal gland on the borderline between pathology and normality. Only a small percentage of patients present with symptoms and a surgical treatment is indicated in highly selected cases. A melatonin secretion in patients with a pineal cyst before and after a pineal cyst resection has not been studied yet and the effect of surgery on human metabolism is unknown. The present study examined melatonin, cortisol and blood glucose secretion profiles perioperatively in a surgical group of 4 patients. The control group was represented by 3 asymptomatic patients with a pineal cyst. For each patient, 24-h circadian secretion curves of melatonin, cortisol and glycemia were acquired. An analysis of melatonin profiles showed an expected diurnal pattern with the night peak in patients before the surgery and in the control group. In contrast, melatonin levels in patients after the surgery were at their minimum throughout the whole 24-h period. The cortisol secretion was substantially increased in patients after the surgery. Blood glucose sampling showed no statistically significant differences. Clinical results demonstrated statistically significant headache relief measured by Visual Analogue Scale in patients after the surgery. Despite the small number of examined patients, we can conclude that patients with a pineal cyst preserved the physiological secretion of the hormone melatonin while patients who underwent the pineal cyst resection experienced a loss of endogenous pineal melatonin production, which equated with pinealectomy. Surprisingly, cortisol secretion substantially increased in patients after the surgery.

• MeSH
• biologické markery krev   MeSH
• bolesti hlavy MeSH
• cirkadiánní rytmus fyziologie   MeSH
• cysty krev   chirurgie   MeSH
• dospělí MeSH
• epifýza mozková metabolismus   chirurgie   MeSH
• hydrokortison krev   sekrece   MeSH
• lidé středního věku MeSH
• lidé MeSH
• melatonin krev   sekrece   MeSH
• mladý dospělý MeSH
• nádory mozku MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

To improve the knowledge in chronophysiology we investigated the causal link between the most important physiological variable studied until now; ten Sarda ewes and ten Sarda goats, pluriparus not pregnant and no lactating, were used. Animals were housed under natural environmental conditions in a common stall, alfalfa hay and water were available ad libitum. Each animal was equipped with an Actiwatch-Mini® for recording total activity. Blood samples were collected every 4 h over a 48 h period for the assessment of melatonin concentration. Rectal temperature was recorded with a digital thermometer immediately before the blood sampling at each data point. Single cosinor method showed a daily rhythm of studied variables. Higher MESOR and amplitude values of melatonin and rectal temperature were observed in sheep than in goats. The diurnal acrophase of locomotor activity was statistically different from the nocturnal acrophase of melatonin and rectal temperature, with no differences between the two species. Robustness was statistically lower in total locomotor activity in comparison with the others two variables, with a differences due to species in melatonin daily rhythm. In conclusion, in small ruminants, melatonin and rectal temperature daily rhythms are strictly correlated, and are not associated with the locomotor activity rhythm.

• MeSH
• cirkadiánní rytmus * fyziologie   MeSH
• kozy fyziologie   MeSH
• melatonin * krev   MeSH
• multivariační analýza MeSH
• ovce fyziologie   MeSH
• pohybová aktivita fyziologie   MeSH
• tělesná teplota * fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

The influence of steroid hormones on food intake is well described. However, there are only a few studies on the effect of food intake on steroid levels. The study involved eight non-smoker women (average age 29.48±2.99 years; average BMI 21.3±1.3 kg/m2); they did not use any kind of medication affecting steroidogenesis. We analysed the influence of four various stimuli on the levels of steroid hormones and melatonin. During their follicular phase of menstrual cycle, each woman had an oral glucose tolerance test (OGTT), intravenous glucose tolerance test (IVGTT), a standard breakfast and psyllium (a non-caloric fibre). Cortisol declined during each test, which is a physiological decline in the morning hours. In all tests (except of the application of the non-caloric fibre, psyllium), however, this decline was modified. After the standard breakfast there was an increase in cortisol at 40th minute. The OGTT and IVGTT tests led to a plateau in cortisol levels. Testosterone levels and those of other steroid hormones showed no relationships to tested stimulations. Oral and intravenous glucose have influenced physiological decline of melatonin levels. During the IVGTT test, melatonin levels started to increase at 20th minute, reaching a maximum at 40th minute. The OGTT test led to a delayed increase in melatonin levels, compared to IVGTT. Despite the fact that we performed the tests in the morning hours, when steroid hormone levels physiologically start to change due to their diurnal rhythm, we still found that food intake influences some of the hormone levels.

• MeSH
• cirkadiánní rytmus fyziologie   MeSH
• dehydroepiandrosteron krev   MeSH
• dospělí MeSH
• energetický příjem fyziologie   MeSH
• glukózový toleranční test MeSH
• hydrokortison krev   MeSH
• lidé MeSH
• melatonin krev   MeSH
• přijímání potravy fyziologie   MeSH
• testosteron krev   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The aim of the study was to establish and optimize an electrochemical method for the assay of low-molecular-weight antioxidants (LMWA). We used square-wave vol¬tammetry (at 0–1.1 V) on screen-printed sensors with C working electrodes. Optimum parameters were: potential step and amplitude 5 mV and frequency 1 Hz. Ascorbic acid, trolox, N-acetylcysteine and melatonin were used as standard antioxidants to test the linearity and sensitivity of the method. Limits of detection were 0.09 mmol l–1 for ascorbic acid, 0.04 mmol l–1 for melatonin, 0.03 mmol l–1 for trolox, and 0.07 mmol l–1 for N-acetylcysteine. 20 ??????l samples were used. The suitability of the method for the assay was confirmed by the standard ferric reducing ability of plasma test. Both methods correlated well (correlation coefficient 0.9778).

• MeSH
• antioxidancia * analýza   MeSH
• chemické techniky analytické metody   přístrojové vybavení   využití   MeSH
• cystein analýza   krev   MeSH
• elektrochemické techniky * metody   přístrojové vybavení   využití   MeSH
• glutathion analýza   krev   MeSH
• krevní plazma * MeSH
• kyselina askorbová * analýza   krev   MeSH
• kyselina močová analýza   krev   MeSH
• lidé MeSH
• melatonin analýza   krev   MeSH
• metody pro přípravu analytických vzorků metody   přístrojové vybavení   MeSH
• oxidační stres MeSH
• reaktivní formy kyslíku chemie   MeSH
• tokoferoly analýza   krev   MeSH
• vitamin A analýza   krev   MeSH
• volné radikály chemie   MeSH
• Check Tag
• lidé MeSH

Impaired daily rhythms in vertebrate physiology occur with age. Particularly, age-related changes in melatonin and serotonin rhythms and hypercortisolemia have been reported to be linked to age-related disorders. This study was aimed at assessing the effect of a Jerte Valley cherry-based nutraceutical product (patent no ES 2342141 B1), which contains high levels of tryptophan, serotonin, and melatonin, on the serum melatonin, serotonin, corticosterone, and total antioxidant capacity (TAC) levels in young and old ring doves (Streptopelia risoria) and rats (Rattus norvegicus) as representatives of animals with diurnal and nocturnal habits, respectively. The animals consumed the cherry product for 10 days. Serum melatonin, serotonin, corticosterone, and TAC were measured with commercial ELISA kits. The consumption of the cherry product induced a significant increase in the circulating levels of melatonin and serotonin, as well as in the serum TAC and a significant decrease in the circulating levels of corticosterone in both species and groups of age as compared to their respective values in the control groups. The consumption of a Jerte Valley cherry-based nutraceutical product may help to counteract the decrease in melatonin and serotonin and the increase in oxidative stress, suggesting a potential health benefit especially in aged populations where these parameters have been found to be altered.

• MeSH
• antioxidancia MeSH
• cirkadiánní rytmus fyziologie   genetika   účinky léků   MeSH
• Columbidae MeSH
• ELISA metody   využití   MeSH
• experimenty na zvířatech MeSH
• financování organizované MeSH
• kortikosteron krev   MeSH
• Malpighiaceae MeSH
• melatonin izolace a purifikace   krev   MeSH
• potkani Wistar MeSH
• serotonin izolace a purifikace   krev   MeSH
• stárnutí MeSH
• statistika jako téma MeSH
• věkové faktory MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH

Three spectral components with periods of about (~) 0.41, ~0.5 and ~1.0 year had been found with serially independent sampling in human circulating melatonin. The time series consisted of around-the-clock samples collected for 24 hours at 4-hour intervals from different patients over several years. Some of these components had been found to be circadian stage-dependent, the daytime measurements following mostly a circannual variation, whereas a half-year characterized the nighttime samples. The latter were incorporated into a circasemiannual map. The relative brevity of the series prevented a check for the coexistence of all three spectral components, even if each component seemed to have a raison d'etre. In time series of transdisciplinary data, a 1.00-year synchronized component is interpreted as representing the seasons. The half-year may qualify the circannual waveform, but it is also a signature of geomagnetics. An ~0.41-year (~5-month) component is the signature of solar flares. It has been called a cis-half-year (cis = on this side of a half-year) and may be detected only intermittently. Charles L. Wolff predicted the existence, among others, of ~0.42- and ~0.56-year components as beat periods of rotations at different solar latitudes.The multiple components characterizing circulating melatonin could also be found in a (to our knowledge unique) data set of a clinically healthy scientist (RBS). Herein, we focus on vascular data self-measured by RBS as he aged from ~20 to ~60 years. A multi-component model consisting of cosine curves with periods of 0.41, 0.50 and 1.00 year was fitted to weekly means of systolic (S) and diastolic (D) blood pressure (BP) and heart rate (HR) collected ~5 times a day over 39 years by RBS. All three components can coexist for a while, although all of them are nonstationary in their characteristics and come and go by the criterion of statistical significance.Intermittently, BP and HR are synchronized selectively with one or the other aspect of RBS' physical environment, namely the seasons (at ~1.0 year), earth magnetism (at ~0.5 year) and/or solar flares (at ~0.42 year). Cosmic-biotic transfer of information, albeit hardly of energy (the biospheric amplitudes are very small) may be mediated in this set of frequency windows. As found earlier, RBS' circulation is also frequency-trapped environmentally in multidecadal windows, HR being locked into the transtridecadal Brückner, or rather Brückner-Egeson-Lockyer, BEL sunspot and terrestrial weather cycle, while his BP follows Hale's didecadal cycle in the changing polarity of sunspots.The ~0.41-year HR cycle may be associated with changes in solar flares, the cis-half-year amplitude of HR showing a cross-correlation coefficient of 0.79 with the total solar flare index (from both solar hemispheres) at a lag of ~3.2 years. The superposed time courses of these two variables indicate the presence of a shared Horrebow-Arago-Schwabe sunspot cycle of ~11 years, the cis-half-year in HR being more prominent after the total solar flare index reaches its ~11-year peak. Differences in the time-varying behavior of BP vs. HR are also described.

• MeSH
• ambulantní monitorování krevního tlaku MeSH
• časové faktory MeSH
• chronobiologické jevy fyziologie   MeSH
• cirkadiánní rytmus fyziologie   MeSH
• financování organizované MeSH
• krevní tlak fyziologie   MeSH
• lidé MeSH
• magnetismus MeSH
• melatonin fyziologie   krev   MeSH
• roční období MeSH
• sluneční aktivita MeSH
• srdeční frekvence fyziologie   MeSH
• Země (planeta) MeSH
• Check Tag
• lidé MeSH