Thesis (PH. D.)--Michigan State University. Dept. of Psychology, 2008. / Title from PDF t.p. (viewed on Sept. 8, 2009) Includes bibliographical references (p. 157-178). Also issued in print.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xii, 153 p.; also includes graphics (some col.) Includes bibliographical references (p. 132-153). Available online via OhioLINK's ETD Center

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 198-229).

Το μεταβολικό σύνδρομο, αποτελεί ένα σύνολο διαταραχών, όπως η κοιλιακή παχυσαρκία, η υπεργλυκαιμία, η χαμηλή HDL χοληστερόλη (HDL-C), τα αυξημένα τριγλυκερίδια (ΤRG) και η υπέρταση. Αν και η συχνότητα του παρουσιάζεται συνεχώς αυξανόμενη παγκοσμίως, η παθογένειά του, καθώς και τα διαγνωστικά κριτήρια, παραμένουν όχι σαφώς προσδιορισμένα. Φαίνεται να σχετίζεται με τη δραστηριότητα του άξονα ΥΥΕ, όμως ο υποκείμενος μηχανισμός παραμένει ασαφής. Σκοπός της παρούσης μελέτης ήταν να διερευνήσουμε τη λειτουργία του άξονα ΥΥΕ σε ασθενείς με μεταβολικό σύνδρομο και να εξετάσουμε αν η δραστηριότητα του άξονα ΥΥΕ σχετίζεται με τα επί μέρους στοιχεία του μεταβολικού συνδρόμου. Υλικό και Μέθοδος: Μελετήθηκαν 159 συνολικά άτομα, τα οποία χωρίστηκαν σε δύο ομάδες. Η πρώτη ομάδα (ομάδα ατόμων με μεταβολικό σύνδρομο) περιελάμβανε 86 άτομα με μεταβολικό σύνδρομο, 48 άνδρες και 38 γυναίκες, μέσης ηλικίας 52.2±7.6 έτη, mean±SD, και με δείκτη σωματικής μάζας 30.5±5.35 kg/m², mean±SD. Η δεύτερη ομάδα (ομάδα ελέγχου) περιελάμβανε 73 υγιή άτομα (μάρτυρες), 19 άνδρες και 54 γυναίκες, μέσης ηλικίας 49.9±7.5 έτη, mean±SD, και με δείκτη μάζας σώματος 27.9±4.42 kg/m², mean±SD. Οι δύο ομάδες ήταν συγκρίσιμες ως προς την ηλικία. Όλα τα άτομα υπεβλήθησαν σε δοκιμασία ανοχής 75g γλυκόζης από το στόμα (OGTT) μετά από νηστεία 12 ωρών, και δείγματα αίματος ελήφθησαν για τον προσδιορισμό της ACTH, της κορτιζόλης, της ινσουλίνης, του C-πεπτιδίου και της γλυκόζης. Τα επίπεδα κορτιζόλης ορού μετά από δοκιμασία ολονύκτιας καταστολής με 1mg δεξαμεθαζόνης (DXM) μετρήθηκαν και στις δύο ομάδες. Αποτελέσματα: Οι ασθενείς με μεταβολικό σύνδρομο είχαν στατιστικώς σημαντικά υψηλότερα επίπεδα κορτιζόλης ορού μετά από ολονύκτια δοκιμασία καταστολής με δεξαμεθαζόνη σε σχέση με τους υγιείς μάρτυρες. Καθ’όλη τη διάρκεια της δοκιμασίας ΟGTT τα επίπεδα της ΑCTH πλάσματος ήταν υψηλότερα στην ομάδα με μεταβολικό σύνδρομο σε σύγκριση με την ομάδα ελέγχου, ενώ τα επίπεδα κορτιζόλης ορού ήταν συγκρίσιμα μεταξύ των δύο ομάδων. Σε όλους τους χρόνους της δοκιμασίας OGTT τα επίπεδα της γλυκόζης, της ινσουλίνης και του C-πεπτιδίου ήταν στατιστικώς σημαντικά υψηλότερα στην ομάδα με μεταβολικό σύνδρομο σε σύγκριση με την ομάδα ελέγχου. Επίσης, η ΑCTH κατά τη δοκιμασία OGTT παρουσίασε στατιστικώς σημαντική θετική συσχέτιση με το μεταβολικό σύνδρομο και τα περισσότερα στοιχεία του, ενώ δεν βρέθηκε συσχέτιση μεταξύ της κορτιζόλης κατά τη διάρκεια της δοκιμασίας OGTT και του μεταβολικού συνδρόμου. Συμπεράσματα: Ο άξονας ΥΥΕ φαίνεται να είναι περισσότερο δραστήριος στους ασθενείς με μεταβολικό σύνδρομο, όπως αποδεικνύεται από τα υψηλότερα επίπεδα κορτιζόλης μετά από ολονύκτια δοκιμασία καταστολής με δεξαμεθαζόνη και τα αυξημένα επίπεδα ACTH κατά τη διάρκεια της δοκιμασίας OGTT. Το εύρημα αυτό ενισχύει την άποψη ότι υφίσταται «λειτουργική» υπερκορτιζολαιμία στην εκδήλωση του μεταβολικού συνδρόμου. / Metabolic syndrome (MetS) is correlated with the activity of Hypothalamic-Pituitary-Adrenal axis (HPA) but the underlying mechanism still remains elusive.The aim of this study was to investigate the HPA axis function in patients with MetS. Materials/Methods: This case-control study included 159 people. They were divided into 2 groups. The first group included 73 healthy volunteers (control group: 19 male, 54 female, mean±SD: 49.9±7.5 years old, with BMI: 27.9±4.42 kg/m2) and the second group included 86 patients with MetS (case group: 48 male, 38 female, mean±SD: 52.2±7.6 years old, with BMI: 30.5±5.35 kg/m2). An oral glucose tolerance test (OGTT) was performed for all subjects after a 12-h overnight fast, and blood samples were obtained for determination of ACTH, cortisol, insulin, C-peptide, and glucose levels. Serum cortisol after an overnight dexamethasone suppression test was determined in both groups. Results: Patients with MetS had serum cortisol levels after an overnight dexamethasone suppression test significantly higher than controls. During OGTT plasma ACTH levels were higher at all time points in patients with MetS compared to controls, whereas serum cortisol levels were comparable between the 2 groups. Plasma ACTH during OGTT was also correlated with most of the components of MetS. Conclusions: The HPA axis in patients with MetS seems to be more active as evidenced by the higher cortisol levels after the overnight dexamethasone suppression test and by the higher ACTH levels during OGTT. This functional hypercortisolism might be involved in the pathogenesis of the metabolic syndrome.

abstract: Dysregulated cortisol has been linked to a variety of adverse physical and psychological consequences. Stressors in the childhood family environment can influence cortisol activity throughout development. For example, research has shown that both infants and children of depressed mothers exhibit altered levels of cortisol compared to infants and children of non-depressed mothers. It is unclear, however, whether exposure to maternal depression in childhood and adolescence is related to cortisol activity at later stages of development. The current study examined the longitudinal relation between maternal depressive symptoms during late childhood (9-12 years old) and adolescence (15-19 years old) and cortisol activity in offspring in young adulthood (24- 28 years old) in a sample of 40 young adults and their mothers. Maternal depressive symptoms were prospectively assessed at four time points across the 15 year study. Cortisol samples were collected from young adult offspring at the final time point. Findings revealed that higher levels of maternal depressive symptoms during late childhood were associated with lower total cortisol output in young adulthood. Results suggest that attenuated cortisol levels, which put these young adults at risk for a variety of stress-related physical and psychological illnesses, may be a long-term consequence of exposure to maternal depression,. Depressive symptoms in mothers during their child's adolescence, however, did not relate to cortisol output. These findings suggest a sensitive period in late childhood during which the development of HPA activity may be susceptible to the environmental stressor of maternal depression. / Dissertation/Thesis / M.A. Psychology 2011

La réduction du temps de sommeil est un phénomène de plus en plus courant. Un faisceau de données expérimentales et épidémiologiques suggère qu'un manque de sommeil pourrait être un facteur de risque d'obésité et de diabète. Dans un premier temps, puisque des modifications de l'axe Hypothalamo-Hypophyso-Surrénalien (HHS) pourraient sous- tendre la relation entre le manque de sommeil et les maladies métaboliques, j'ai évalué les effets de 2 nuits courtes sur ce système chez des jeunes hommes en bonne santé. Nous avons montré que 2 nuits de 4h au lit altéraient l'activité spontanée et la réactivité de l'axe HHS et que l'ampleur des altérations était corrélée à l'importance de la privation de sommeil. Dans un deuxième temps, j'ai tenté de déterminer si une extension de sommeil pouvait avoir des effets bénéfiques chez des jeunes obèses dormant habituellement peu. Nos résultats préliminaires montrent que par simple extension du temps passé au lit, des obèses dormant habituellement 6h, étaient capables de dormir 8h, une durée associée au plus faible risque d'obésité dans les études épidémiologiques, que leur appétit pour les aliments gras et salés et le grignotage diminuaient, que leurs taux de polypeptide pancréatique, une hormone anorexigène, étaient augmentés, et que leur prise calorique lors d'un buffet à volonté était d'autant plus diminuée que leur temps de sommeil était augmenté. Ce travail souligne l'importance d'une durée de sommeil suffisante pour une bonne santé métabolique et suggère que l'optimisation du sommeil pourrait constituer une alternative peu coûteuse pour la prévention et la prise en charge des maladies métaboliques / Voluntary sleep restriction is increasingly common in modern socities. Evidence from epidemiological and experimental studies suggest that sleep loss may be a risk factor for obesity and type 2 diabetes. First, since the modifications in Hypothalamic-Pituitary-adrenal (HPA) axis activity may underlie the relationship between sleep loss and metabolic diseases, 1 evaluated the effect of 2 short nights on this system in healthy lean young men. We showed that 2 nights of 4h in bed impaired spontaneous activity and the reactivity of the HPA axis and that the magnitude of these alterations was related of the severity of sleep loss. 1n a second step, 1 sought to determine if sleep extension could have a beneficial effect in young obese short sleepers. Our preliminary results showed that, by a simple bedtime extension, obese subjects usually sleeping 6h were able to sleep 8h, a duration associated with the lowest risk obesity risk in epidemiological studies. Moreover, their appetite for sweets and fat food, and snacking were decreased, the levels of pancreatic polypeptide, an anorexigenic hormone, were increased and the more they slept, the less they consumed calories at an ad libitum buffet. This work highlights the importance of getting enough sleep to maintain a good metabolic health and suggest that sleep optimization may have implications for novel public health interventions

abstract: Sleep is essential for physical and psychological health. Sleep has also been linked to the daily patterns of key stress-responsive physiological systems, specifically the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS). Extant research examining sleep and diurnal patterns of cortisol, the primary end product of the HPA axis, is inconsistent. Moreover, it is not clear how specific aspects of sleep behavior (e.g., sleep duration, sleep quality, sleep variability) are related to specific components of diurnal cortisol rhythms. Salivary alpha-amylase (sAA) has been recognized as a surrogate marker of ANS activity, but limited research has explored relations between sleep and sAA diurnal rhythms. The current study utilized a modified ecological momentary assessment protocol to examine within- and between-person relations between multiple facets of sleep behavior using multiple methods (e.g., subjective report, actigraphy) and salivary cortisol and sAA. First year college students (N = 76) provided saliva samples and diary entries five times per day over the course of three days. Sleep was assessed via questionnaire, through daily diaries, and monitored objectively using actigraphy over a four day period. Between-person results revealed that shorter average sleep duration and greater sleep variability was related to lower levels of waking cortisol and flatter diurnal slopes across the day. Within-person results revealed that on nights when individuals slept for shorter durations than usual they also had lower levels of waking cortisol the next day. Sleep was not related to the cortisol awakening response (CAR) or diurnal patterns of sAA, in either between-person or within-person analyses. However, typical sleep behaviors measured via questionnaire were related to waking levels of sAA. Overall, this study provides a greater understanding of how multiple components of sleep, measured in naturalistic environments, is related to cortisol and sAA diurnal rhythms, and how day-to-day, within-person changes in sleep duration contribute to daily variations in cortisol. / Dissertation/Thesis / Masters Thesis Psychology 2015

Made available in DSpace on 2014-06-11T19:22:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-03-21Bitstream added on 2014-06-13T20:07:59Z : No. of bitstreams: 1 pauli_jr_me_rcla.pdf: 1649366 bytes, checksum: 582a2977521476b101c59041c4c0ec5e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Existem consideráveis evidências demonstrando que tanto animais quanto humanos tratados com glicocorticóides freqüentemente apresentam anormalidades no metabolismo de carboidratos, proteínas e gorduras. Os objetivos do presente estudo foram: 1) investigar as adaptações endócrino-metabólicas em ratos submetidos ao exercício físico agudo e crônico de natação associado com a administração de dexametasona durante 10 semanas. 2) analisar os efeitos do treinamento associado à utilização de baixas doses de dexametasona na funcionalidade do eixo hipotálamo-hipófise-adrenal. Com os resultados obtidos concluímos que: 1) baixa dose de dexametasona promove diversos efeitos colaterais no metabolismo intermediário. O uso crônico deste esteróide tem um importante papel no desenvolvimento da resistência à insulina periférica. A insulino resistência é um importante fator para o desenvolvimento do diabetes mellitus, hipertensão, menor tolerância aos carboidratos, e alteração lipídica; 2) o exercício regular de natação promove aumento na sensitividade à insulina e reverte estes aspectos. Alem disso, o treinamento físico promove o aumento dos estoques de energia no músculo e fígado e contribui para um menor acúmulo de tecido adiposo epididimal; 3) o exercício pode ainda preponderar sobre o feedback negativo da dexametasona na ativação do eixo hipotálamo-hipofisiário-adrenal em ratos. / There is considerable evidence that abnormalities of carbohydrate, protein and fat metabolism occur frequently to both animals and humans treated with glucocorticoid. The aims of this study were: 1) to investigate the endocrine-metabolic adaptations in rats submitted to acute and chronic swimming exercise associate to administration of dexamethasone during 10 weeks; 2) to analyze the effects of training associate to low-dose dexamethasone on the hypothalamic-pituitary-adrenal axis. The results obtained led us to conclude that: 1) Low-dose of dexamethasone promotes several side effects in intermediary metabolism. The chronic use of this steroid has an important role in the development of peripheral insulin resistance. Insulin resistance may be an important factor for the development of diabetes mellitus, hypertension, impaired carbohydrate tolerance, and lipid alteration; 2) the regular swimming exercise promoted increased insulin sensitivity and reverted this aspect. Moreover, physical training increased energy stores in muscle and liver and contributed to the lower adipose epididimal tissue accumulation; 3) Therefore, exercise can override the dexamethasone negative feedback of hypothalamy-pituitary-adrenal axis activation in rats.

Orientador: Eliete Luciano / Banca: Gustavo Puggina Roggato / Banca: Maria Alice Rostom de Mello / Resumo: Existem consideráveis evidências demonstrando que tanto animais quanto humanos tratados com glicocorticóides freqüentemente apresentam anormalidades no metabolismo de carboidratos, proteínas e gorduras. Os objetivos do presente estudo foram: 1) investigar as adaptações endócrino-metabólicas em ratos submetidos ao exercício físico agudo e crônico de natação associado com a administração de dexametasona durante 10 semanas. 2) analisar os efeitos do treinamento associado à utilização de baixas doses de dexametasona na funcionalidade do eixo hipotálamo-hipófise-adrenal. Com os resultados obtidos concluímos que: 1) baixa dose de dexametasona promove diversos efeitos colaterais no metabolismo intermediário. O uso crônico deste esteróide tem um importante papel no desenvolvimento da resistência à insulina periférica. A insulino resistência é um importante fator para o desenvolvimento do diabetes mellitus, hipertensão, menor tolerância aos carboidratos, e alteração lipídica; 2) o exercício regular de natação promove aumento na sensitividade à insulina e reverte estes aspectos. Alem disso, o treinamento físico promove o aumento dos estoques de energia no músculo e fígado e contribui para um menor acúmulo de tecido adiposo epididimal; 3) o exercício pode ainda preponderar sobre o feedback negativo da dexametasona na ativação do eixo hipotálamo-hipofisiário-adrenal em ratos / Abstract: There is considerable evidence that abnormalities of carbohydrate, protein and fat metabolism occur frequently to both animals and humans treated with glucocorticoid. The aims of this study were: 1) to investigate the endocrine-metabolic adaptations in rats submitted to acute and chronic swimming exercise associate to administration of dexamethasone during 10 weeks; 2) to analyze the effects of training associate to low-dose dexamethasone on the hypothalamic-pituitary-adrenal axis. The results obtained led us to conclude that: 1) Low-dose of dexamethasone promotes several side effects in intermediary metabolism. The chronic use of this steroid has an important role in the development of peripheral insulin resistance. Insulin resistance may be an important factor for the development of diabetes mellitus, hypertension, impaired carbohydrate tolerance, and lipid alteration; 2) the regular swimming exercise promoted increased insulin sensitivity and reverted this aspect. Moreover, physical training increased energy stores in muscle and liver and contributed to the lower adipose epididimal tissue accumulation; 3) Therefore, exercise can override the dexamethasone negative feedback of hypothalamy-pituitary-adrenal axis activation in rats / Mestre

No description available.