Interrelations between acute and chronic exercise and the immune and endocrine systems

Interaction between the endocrine and immune system is necessary to regulate our health. However, under some conditions, stress hormones can overstimulate or suppress the immune system, resulting in harmful consequences (1). Stress is often considered negative, yet it is an intrinsic part of everyday life. Stress is not clearly defined; it is context-specific and depends on the nature of factors that challenge our body. Internal stimuli will elicit different stress reactions compared with external stimuli (1). Similarly, some stressors will induce responses that may benefit survival, whereas others will cause disturbances that may endanger our health. Stress also depends on how our bodies perceive and respond to stressful stimuli (1).

Managing the transition : the role of optimism and self-efficacy for first-year Australian university students

Students making the transition from high school to university often encounter many stressors and new experiences. Many students adjust successfully to university; however, some students do not, often resulting in attrition from the university and mental health issues. The primary aim of the current study was to examine the effects that optimism, self-efficacy, depression, and anxiety have on an individual's life stress and adaptation to university. Eighty-four first-year, full-time students from the Queensland University of Technology (60 female, 24 male) who had entered university straight from high school completed the study. Participants completed a questionnaire assessing their levels of optimism, self-efficacy, depression, anxiety, perceived level of life stress and adaptation to university. In line with predictions, results showed that optimism, depression, and anxiety each had a significant relationship with students’ perceived level of stress. Furthermore, self-efficacy and depression had a significant relationship with adaptation to university. We conclude that students with high levels of optimism and low levels of depression and anxiety will adapt better when making the transition from high school to university. In addition, students with high levels of self-efficacy and low levels of depression will experience less life stress in their commencement year of university. The implications of this study are outlined.

Psychological predictors of injury among elite athletes

Objectives: To establish injury rates among a population of elite athletes, to provide normative data for psychological variables hypothesised to be predictive of sport injuries, and to establish relations between measures of mood, perceived life stress, and injury characteristics as a precursor to introducing a psychological intervention to ameliorate the injury problem. Methods: As part of annual screening procedures, athletes at the Queensland Academy of Sport report medical and psychological status. Data from 845 screenings (433 female and 412 male athletes) were reviewed. Population specific tables of normative data were established for the Brunel mood scale and the perceived stress scale. Results: About 67% of athletes were injured each year, and about 18% were injured at the time of screening. Fifty percent of variance in stress scores could be predicted from mood scores, especially for vigour, depression, and tension. Mood and stress scores collectively had significant utility in predicting injury characteristics. Injury status (current, healed, no injury) was correctly classified with 39% accuracy, and back pain with 48% accuracy. Among a subset of 233 uninjured athletes (116 female and 117 male), five mood dimensions (anger, confusion, fatigue, tension, depression) were significantly related to orthopaedic incidents over the preceding 12 months, with each mood dimension explaining 6–7% of the variance. No sex differences in these relations were found. Conclusions: The findings support suggestions that psychological measures have utility in predicting athletic injury, although the relatively modest explained variance highlights the need to also include underlying physiological indicators of allostatic load, such as stress hormones, in predictive models.

Psychological screening and injury among elite athletes

The purpose of the present investigation was to evaluate the effectiveness of the psychological component of the Queensland Academy of Sport (QAS) Health Screening Questionnaire in screening for injury/illness characteristics among elite athletes. In total, 793 scholarship athletes (409 females and 384 males) ranging in age from 11 to 41 years (M = 19, SD = 4.4) across 20 sports at the QAS in Brisbane, Australia, completed the QAS Health Screening Questionnaire. Psychological risk factors examined were life stress and mood, as measured by the Perceived Stress Scale - 10 (PSS-10) and the Brunel Mood Scale (BRUMS) respectively, in addition to disordered eating behaviours and history of diagnosed psychological disorders. Medical risk factors examined included asthma and back pain. Single-factor MANOVAs showed multivaritate effects for injury, second injury, back pain, asthma, anxiety disorder diagnosis, and fasting. Discriminant function analyses demonstrated that life stress and mood scores had significant utility in correctly classifying injury and second injury status, asthma, back pain, anxiety, and eating disorder diagnosis, in addition to the use of fasting and vomiting as weight control methods. The present findings suggest that the psychology component of the QAS Health Screening Questionnaire demonstrates significant utility as a screening tool regarding injury/illness characteristics among elite athletes.

Psychological predictors of injury in elite athletes

The Queensland Academy of Sport (QAS) supports over 600 high-level athletes across 20 sports. Given the high cost of injuries (e.g., time out of sport and consequent detraining, expense of rehabilitation, adverse social and economic effects), comprehensive injury management and prevention has become a priority for the QAS. Considering the potential for developing cost-effective, preventative programs, knowledge gained by examination of psychological screening predictors of injury may also prove beneficial for the broader sports medicine community. Aims were to: Objectively summarise existing injury characteristics, including the creation of population-specific norms for scholarship holders at the QAS. Assess relationships between injuries, specific medical factors (e.g., asthma, back pain) and psychological risk factors including life stress, mood, previous psychological diagnoses and disordered eating behaviour over a three-year period. Evaluate the effectiveness of the psychological component of the QAS Health Screening Questionnaire.

Coping style and ecstasy use motives as predictors of current mood symptoms in ecstasy users

Background Elevated depressive and anxiety symptoms during childhood and adolescence have been associated with greater risk of later ecstasy use. Ecstasy users have reported using ecstasy to reduce depression or worry, or to escape. While these findings suggest that some people use ecstasy as a form of self-medication, limited research has been conducted examining the relationship between affective symptoms, coping styles and drug use motives in ecstasy users. This cross-sectional study aimed to determine if coping style and/or ecstasy use motives are associated with current mood symptoms in ecstasy users. Methods A community sample (n = 184) of 18–35 year olds who had taken ecstasy at least once in the past 12 months completed self-report measures of depression, anxiety, ecstasy use motives and coping styles. Timeline followback methods were used to collect information on lifetime ecstasy, recent drug use and life stress. Trauma exposure was measured using the Composite International Diagnostic Interview—Trauma List. Results Coping motives for ecstasy use and an emotion-focused coping style were significantly associated with current depressive and anxiety symptoms. Emotion-focused coping mediated the relationship between a history of trauma and current anxiety symptoms and moderated the relationship between recent stressful life events and current depressive symptoms. Conclusions These findings highlight the importance of interventions targeting motives for ecstasy use, and providing coping skills training for managing stressful life events among people with co-occurring depressive/anxiety symptoms and ecstasy use.

Aspectos psicossociais do impedimento laboral por motivos de saúde em trabalhadores de cozinhas industriais

Este estudo teve por objetivo investigar a relação trabalho / saúde em trabalhadores de cozinhas industriais, focalizando o aspecto socioeconômico e outras dimensões da vida social (estresse no trabalho e eventos de vida produtores de estresse), incluindo-se morbidade (obesidade, doenças crônicas e transtornos mentais comuns), condição laboral (incômodos ambientais e acidentes de trabalho) e comportamentos relacionados à saúde (consumo alimentar, tabagismo e álcool). Utilizando dados coletados nos nove Restaurantes Populares do Estado do Rio de Janeiro, apresentam-se três artigos. O primeiro descreve a população de estudo, considerando três grupos ocupacionais: Administrativos, Cozinheiros e Copeiros, e os Auxiliares de Serviços Gerais. O segundo artigo investiga a associação entre as características psicossociais e o impedimento laboral por motivos de saúde, considerando uma análise hierarquizada e, finalmente, o terceiro artigo discute a certificação da reprodutibilidade, na população de estudo, do questionário sueco da versão para o português do Demand-Control Questionnaire (DCQ), utilizado para avaliar estresse no ambiente de trabalho. Os homens representaram 62,7% do total de trabalhadores. A idade média dos funcionários foi de 35,1 anos, (DP=10,3). A renda familiar líquida foi de até dois salários mínimos para 60% dos trabalhadores. Obteve-se para o tempo de trabalho em cozinhas, uma média de 59,8 meses, tendo variado de um mínimo de 2 meses e máximo de 30 anos. A prevalência de doenças que tinham diagnóstico médico foi de 15,0% para Doença Osteomusculares Relacionadas ao Trabalho (DORT); 14,3% para Hipertensão Arterial Sistêmica; 12,7% para Gastrite; e, 2,1% para Diabete Mellitus tipo II. O acidente de trabalho corte foi relatado por 20,2% dos trabalhadores, seguido de contusão com 16,0%. A prevalência de acidentes de trabalho foi mais expressiva entre os ASG. A prevalência de impedimento laboral por motivos de saúde foi de 10,8%. Os modelos resultantes das análises multivariadas de associação entre impedimentos das atividades laborais e as variáveis que permaneceram no modelo final após o ajustes das variáveis indicaram que aqueles que referiram estado geral de saúde regular e ruim tiveram uma razão de prevalência de três para impedimento das atividades laborais comparados aos de muito bom e bom estado geral de saúde (RP: 3,59; IC:1,44-8,97). Os trabalhadores que exerciam suas atividades nos restaurante localizados na área 2 (Bangu, Central do Brasil, Maracanã e Niterói) apresentaram RP:2,38; IC:1,15-4,91) para ausências no trabalho quando comparados aos da área 1 (Barra Mansa, Campos, Itaboraí, Duque de Caxias e Nova Iguaçu). A confiabilidade da escala do DCQ, teste-reteste, produziu um Coeficiente de Correlação Intraclasse para as dimensões: demanda psicológica, controle do trabalho e apoio social no trabalho de 0,70, 0,68 e 0,80, respectivamente, sendo considerados bom. Este estudo reforça a importância dos aspectos psicossociais na ocorrência do impedimento por motivos de saúde e contribui para o conhecimento dessas relações. Sugere-se realizar estudos com desenho longitudinal, que permitam aprofundar o conhecimento sobre os determinantes psicossociais do trabalho e o absenteísmo.

Efeitos do controle de temperatura e da vimpocetina sobre os déficits neurocomportamentais decorrentes do estresse por separação materna em camundongos suíços neonatos

O estresse durante o desenvolvimento está associado com diversas desordens neurocomportamentais, que podem persistir ao longo da vida. A hiperatividade é um dos transtornos comportamentais que, com maior frequência, observa-se em humanos submetidos ao estresse precoce. Esse transtorno pode ser a manifestação clínica predominante, ou mesclar-se com déficit de atenção, impulsividade e retardo da aprendizagem, constituindo o Transtorno de Déficit de Atenção e Hiperatividade (TDAH), com número de casos diagnosticados em ascensão. Diversos protocolos experimentais utilizam a separação materna (SM) de roedores neonatos para mimetizar as consequências do estresse precoce em humanos. Esta predileção por roedores recém-nascidos se deve à sua equivalência aproximada com fetos humanos no terceiro trimestre da gestação em termos de neurodesenvolvimento, quando ocorre o maior crescimento do Sistema Nervoso Central fetal. Neste trabalho, camundongos suíços neonatos foram submetidos a sessões diárias de isolamento com separação materna, entre o 2 e o 10 dias de vida pós-natal (PN2 a PN10), variando-se a temperatura de isolamento dos filhotes, que permaneciam sem aquecimento (na temperatura do biotério, entre 22 e 25C) ou eram mantidos aquecidos a 37C durante essas sessões. Portanto, foram três grupos experimentais: isolamento aquecido com SM; isolamento não aquecido com SM; e controle. Os animais do grupo controle foram pesados em PN2 e PN10 e, prontamente, devolvidos às progenitoras. Todos os animais foram desmamados e sexados em PN21, não sendo perturbados até a realização dos testes neurocomportamentais, a partir de PN30, que incluíram os Testes de Campo Aberto e de Esquiva Inibitória. Num segundo estudo, foram realizadas dosagens séricas da corticosterona basal e dos hormônios tireoidianos nos três grupos experimentais, em PN6, PN10 e PN30. Finalmente, num terceiro estudo, camundongos do grupo controle e do grupo submetido ao isolamento não aquecido com SM foram tratados com vimpocetina (20g/kg), um neuroprotetor potencial, ou com veículo (Dimetilsulfóxido), a fim de avaliar os efeitos da vimpocetina na atividade locomotora. O 1 estudo demonstrou que a temperatura foi um fator crítico para a manifestação de hiperatividade locomotora no Teste do Campo Aberto, que ocorreu, somente, nos animais do grupo submetido ao isolamento não aquecido. Adicionalmente, não houve diferenças entre os grupos experimentais no Teste da Esquiva Inibitória, quanto à memória e à aprendizagem. O 2 estudo demonstrou que a temperatura do isolamento influenciou os níveis da corticosterona basal e dos hormônios tireoidianos em PN10 e em PN30. No 3 estudo, a vimpocetina reduziu a hiperatividade locomotora no grupo de animais submetidos ao isolamento não aquecido com SM. De todo o exposto, conclui-se que o isolamento com SM de camundongos suíços neonatos à temperatura de 22 a 25C aumentou a atividade locomotora nesses animais, e que a vimpocetina foi capaz de atenuar esse comportamento, sem aumento da mortalidade. Finalmente, considerando-se o maior risco de desenvolvimento do TDAH em crianças e adolescentes com históricos de prematuridade, levanta-se a hipótese de que o estresse térmico pelo frio seja um dos fatores envolvidos na fisiopatogenia da hiperatividade nesses casos.

Novel insights into the role of the GABAB receptor in depression and anxiety

The GABAB receptor is a functional heterodimer comprising the GABAB1 and GABAB2 subunits, with the GABAB1 subunit displaying two major isoforms, GABAB(1a) and GABAB(1b). Preclinical findings have strongly implicated the GABAB receptor in stress-related psychiatric disorders, however, the precise contribution of the GABAB receptor in depression and anxiety disorders remains unknown. Emerging data suggest that the interaction between adverse environmental conditions, such as early life stress, and a specific genetic composition can increase the risk to develop psychiatric disorders in adulthood. This thesis investigated the role of the GABAB receptor alone or in combination with early-life stress (maternal separation), in modulating antidepressant like and anxiety-related behaviours. Pharmacological blockade of the GABAB receptor with CGP52432 had antidepressant-like behavioural effects. Moreover, mice lacking the GABAB(1b) receptor subunit isoform exhibited antidepressant-like behaviours in adulthood but anxiety-like behaviour in early-life. In response to maternal separation, GABAB(1a)-/- mice exhibited early-life stress-induced anhedonia, a core symptom of depression, while GABAB(1b)-/- mice exhibited a more resilient phenotype. Moreover, when compared with wildtype or GABAB(1a)-/- mice, GABAB(1b)-/- mice that underwent maternal separation exhibited enhanced stressinduced neuronal activation in the hippocampus and in the nucleus accumbens (NAcc), a critical area for anhedonia thus suggesting that enhanced stress-induced neuronal activation in the hippocampus and NAcc in GABAB(1b)-/- mice may be important for their antidepressant-like phenotype and their resilience to stress-induced anhedonia. Pharmacological blockade of GABAB receptor and GABAB(1b) receptor subunit isoform loss of function increased adult hippocampal cell proliferation, thus suggesting that increased hippocampal neurogenesis could be a potential mechanism for the antidepressant-like effects of GABAB receptor antagonists and GABAB(1b) receptor subunit isoform disruption. Finally, this thesis investigated whether the expression of several genes involved in hippocampal neurogenesis or the antidepressant response were altered in the mouse hippocampus following chronic treatment with a GABAB receptor antagonist.

An examination of the impact of dietary lipids on behaviour and neurochemistry

The molecular and cellular basis of stress pathology remains an important research question in biological science. A better understanding of this may enable the development of novel approaches for the treatment of stress-related disorders. There is a considerable body of scientific evidence suggesting that dietary lipids, phospholipids and omega-3 polyunsaturated fatty acids (n-3 PUFAs), have therapeutic potential for certain psychiatric disorders. Thus, we proposed n-3 PUFAs as a novel strategy for the prevention or amelioration of stress-related disorders. We hypothesised that these compounds would improve behavioural and neurobiological responses and alter gut microbial composition. Furthermore, we proposed a new mechanism of action exerted by n-3 PUFAs using an in vitro model of stress. Lastly, we explored the protective effects of both phospholipids and n-3 PUFAs against neuroinflammation, which has been shown to contribute to the development of stress-related disorders. We provide further evidence that glucocorticoids, inflammation and early-life stress induce vulnerability to psychopathologies. Specifically, we have demonstrated that corticosterone (CORT) alters cortical neuron and astrocyte percentage composition, reduces brain-derived-neuronal factor (BDNF) expression, and induces glucocorticoid receptor (GR) down-regulation in mixed cortical cultures. Interestingly, we found that lipopolysaccharide (LPS) treatment resulted in an over-expression of pro-inflammatory cytokines in cortical astrocyte cultures. Moreover, we demonstrate that early-life stress induces changes to the monoaminergic and immune systems as well as altered neuroendocrine response to stressors later in life. In addition, we found that early-life stress alters the gut microbiota in adulthood. These data demonstrate that n-3 PUFAs can attenuate CORT-induced cellular changes, but not those caused by LPS, within the cerebral cortex. Similarly, phospholipids were unable to reverse LPS-induced inflammation in cultured astrocytes. In addition, this thesis proposes that n-3 PUFAs may prevent the development or lessen the symptoms of mental illnesses, ameliorating anxiety- and depressive-like symptoms as well as cognitive effects, particularly when administered during neurodevelopment. Such effects may be mediated by GR activation as well as by modification of the gut microbiota composition. Taken together, our findings suggest that n-3 PUFAs have therapeutic potential for stress-related disorders and we provide evidence for the mechanisms by which they may exert these effects. These findings contribute to an exciting and growing body of research suggesting that nutritional interventions may have an important role to play in the treatment of stress-related psychiatric conditions.

The importance of the gestation period for welfare of lambs: Maternal stressors and lamb vigour and wellbeing

The prenatal period is of critical importance in defining how individuals respond to their environment throughout life. Stress experienced by pregnant females has been shown to have detrimental effects on offspring behaviour, health and productivity. The sheep has been used extensively as a model species to inform human studies. However, in the farmed environment, the consequences for the lamb of the imposition of prenatal stresses upon the ewe have received much less attention. The stressors that pregnant ewes are most frequently exposed to include sub-optimal nutrition and those related to housing, husbandry and environment which may be either acute or chronic. A systematic review of the literature was adopted to identify material which had production-relevant maternal stressors and lamb outcomes. The current review focussed upon the lamb up to weaning around the age of 100 days and the results clearly demonstrate that stressors imposed upon the ewe have implications for offspring welfare and performance. Maternal under-nutrition (UN) in the last third of pregnancy consistently impaired lamb birth-weight and subsequent vigour and performance, while earlier UN had a variable effect on performance. Feeding the ewe above requirements did not have positive effects on lamb performance and welfare. Social and husbandry stressors such as transport, shearing, mixing and physiological treatments designed to mimic acute stress which would be considered disadvantageous for the ewe had positive or neutral effects for the lamb, highlighting a potential conflict between the welfare of the ewe and her lamb. This review also identified considerable gaps in knowledge, particularly in respect of the impact of disease upon the ewe during pregnancy and interactions between different stressors and the responses of ewe and lamb.

Board invited review:The importance of the gestation period for welfare of calves: Maternal stressors and difficult births

The prenatal period is of critical importance in defining how individuals respond to their environment throughout life. Stress experienced by pregnant females has been shown to have detrimental effects on offspring biology in humans and a variety of other species. It also is becoming increasingly apparent that prenatal events can have important consequences for the behavior, health, and productivity of offspring in farmed species. Pregnant cattle may experience many potentially important stressors, for instance, relating to their social environment, housing system and physical environment, interactions with humans and husbandry procedures, and their state of health. We examined the available literature to provide a review of the implications of prenatal stress for offspring welfare in cattle. The long-term effects of dystocia on cattle offspring also are reviewed. To ensure a transparent and repeatable selection process, a systematic review approach was adopted. The research literature clearly demonstrates that prenatal stress and difficult births in beef and dairy cattle both have implications for offspring welfare and performance. Common husbandry practices, such as transport, were shown to influence offspring biology and the importance of environmental variables, including thermal stress and drought, also were highlighted. Maternal disease during pregnancy was shown to negatively impact offspring welfare. Moreover, dystocia-affected calves suffer increased mortality and morbidity, decreased transfer of passive immunity, and important physiological and behavioral changes. This review also identified considerable gaps in our knowledge and understanding of the effects of prenatal stress in cattle. © 2012 American Society of Animal Science. All rights reserved.

Exactitude du rappel de la qualité de vie préopératoire chez les femmes opérées pour une incotinence urinaire à l'effort

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Stresse em expatriados : transpor as fronteiras de si

Esta investigação teve como objetivo avaliar a perceção da Qualidade de Vida nas suas várias dimensões, e como esta pode estar associada à Satisfação no Trabalho. Pretende-se avaliar ainda a relação entre Stresse e a Satisfação no Trabalho, assim como a relação entre perceção do trabalho em contexto de expatriação e a satisfação no trabalho. Na recolha dos dados na plataforma on-line Qualtrics obtivemos 101 questionários válidos. O questionário é constituído pelas seguintes escalas: a WHOQOL-Bref, a 23 QVS de Vaz Serra (2000a), cinco itens da escala de satisfação do trabalho de Lima e colaboradores (1994), e o questionário de expatriados de Camara (2011). Os resultados permitiram concluir que a satisfação com a expatriação apresenta uma relação positiva com a qualidade de vida, assim como também é positiva a relação da satisfação com a perceção do contexto de expatriação. Encontra-se também uma relação negativa da satisfação com o stresse. Com base nos resultados obtidos concluiu-se que a satisfação no trabalho com um processo de expatriação no ponto de vista de quem é o expatriado, depende de vários elementos combinados, sendo, todavia, a maior responsabilidade deste processo atribuída à qualidade de vida.

Vulnerabilidade ao Stresse Profissional e Qualidade de Vida no Trabalho : Estudo empírico numa amostra de cuidadores/as formais de pessoas portadoras de deficiência Cláudia Marques Caçote Leiria

Portugal é dos países com maior índice de stresse da UE, sendo a profissão dos/as cuidadores/as de pessoas deficientes uma das que apresenta maior vulnerabilidade ao stresse profissional em deterioramento da Qualidade de Vida no Trabalho (QVT). Este trabalho visou analisar a relação entre vulnerabilidade ao stresse profissional e QVT nos/as cuidadores/as formais das IPSS de Ourém, com resposta na área da deficiência. A amostra foi composta por 225 colaboradores/as formais. Neste estudo aplicaram-se os instrumentos o inventários QVT de Rafael & Lima (2007) e 23 QVS de Vaz Serra (2000). Os resultados demonstraram que é inexistente a correlação entre QVT (frequência) e vulnerabilidade ao stresse e salientaram a importância do apoio social e familiar no trabalho para a promoção de QVT, sendo o stresse profissional dependente das variáveis habilitações literárias, categoria profissional e tempo de serviço.