Psychophysiological response to social stressors : relevance of sex and age

Understanding the factors involved in the psychophysiological response of people in acute stressful situations is crucial to the prevention and treatment of stress-related health problems. We aim to integrate the results of studies investigating the role of sex and age in the inter-individual variability in several biomarkers of the stress response Methods: We summarize the main findings of our research group and other laboratories regarding sex and age-related differences in the psychophysiological response to psychosocial stress. Results: Sexrelated differences in the stress response are observed in blood pressure and cortisol, but not in heart rate, heart rate variability, or salivary alphaamylase. Additionally, age may explain differences in cortisol levels and basal sympathetic nervous system activity. Conclusions: The results highlight the importance of taking sex and age into account in order to understand the stress response and its possible negative effects on health. Antecedentes: entender los factores involucrados en la respuesta psicofisiológica ante situaciones de estrés agudo es crucial para prevenir y tratar problemas de salud relacionados con el estrés. El objetivo es integrar los resultados de estudios en humanos relacionados con el papel del sexo y la edad en las diferencias individuales en la respuesta de estrés en diferentes biomarcadores. Metodología: se integran los principales resultados de nuestro grupo de investigación y de otros laboratorios centrados en las diferencias debidas al sexo y la edad en la respuesta psicofisiológica a situaciones de estrés psicosocial. Resultados: se observan diferencias en la respuesta de estrés entre hombres y mujeres en presión sanguínea y en niveles de cortisol, pero no en frecuencia cardíaca, variabilidad de la frecuencia cardíaca y alfa-amilasa. Además, la edad influye en los niveles de cortisol y en la actividad basal del sistema nervioso simpático. Conclusiones: los resultados ponen de manifiesto la importancia de tener en cuenta el sexo y la edad de los participantes para poder entender la respuesta de estrés y sus posibles efectos en salud

Efectos del ejercicio físico agudo sobre la respuesta psicofisiológica al estrés: papel modulador de la condición física

La revisión realizada sobre la literatura científica muestra que el ejercicio físico agudo modifica la respuesta psicofisiológica al estrés. Los estudios de laboratorio han empleado diversas variables para estudiar los cambios en estas respuestas. Las variables fisiológicas más estudiadas han sido las cardiovasculares, en las que se produce una respuesta disminuida ante estresores cuando previamente se ha realizado ejercicio. De igual modo, se ha descrito una reducción de la ansiedad tras realizar actividad física de forma puntual. Los cambios en testosterona, en cortisol y en el cociente de ambas hormonas en respuesta al ejercicio físico han sido estudiados y utilizados como indicadores de la adaptación al ejercicio físico y de la respuesta al estrés. La mayor parte de la investigación indica que la condición física modula estas respuestas, obteniéndose en aquellos sujetos con buena forma física resultados positivos sobre la respuesta al estrés y por extensión sobre la salud.Acute physical exercise has been proved to change the psychophysiological stress response. Laboratory research has used several variables to study these responses. Among the most studied physiological variables are cardiovascular measures which decrease in response to stressors carried out after physical exercise. Likewise, a decrease in anxiety has been described after acute bouts of physical exercise. Changes in testosterone, in cortisol and in its ratio in response to physical exercise have been used as indexes of physical exercise adaptation as well as stress response markers. The effects on all these responses are modulated by physical fitness, with better stress responses in subjects in good physical form

Marcadores hormonales del síndrome de sobreentrenamiento

Los programas de entrenamiento deportivo pretenden mejorar el rendimiento mediante la exposición a cargas de trabajo de intensidad creciente. Sin embargo, ocasionalmente se produce una desadaptación, el denominado Síndrome de Sobreentrenamiento (SSE), que perjudica gravemente el rendimiento y la salud del deportista. Para el diagnóstico del SSE se ha reecurrido a diversos marcadores entre los que cabe destacar los hormonales. La monitorización de las hormonas implicadas en la regulación de las respuestas de estrés permite evaluar el grado de adaptación al entrenamiento. Se concluye que el cociente testosterona/cortisol es, actualmente, el marcador con más posibilidades de ser utilizado como instrumento disgnóstico. Sin embargo, se requiere más investigación para clarificar los criterios y las condiciones de su aplicación a diversas especialidades deportivas. Además, se considera el uso complementario de indicadores psicológicos y la necesidad de estudiar las interrelaciones entre ambos tipos de marcadores para comprender más cabalmente la naturaleza e implicaciones globales del síndromeTraining programmes aim to improve sports performance through workloads of increasing intensity. However, sometimes an imbalance appears, the so called Overtraining Syndrome (OTS), which produces enhanced fatigability, health problems and seriously impairs performance. The ability to differentiate between the desadaptative state of OTS and the appropiate adaptation to training, which also frequently involves fatigue states, is a main problem. For this the assessment of the degree of adaptation to training. Testosterone/cortisol ratio is currently the marker with more possibilities to be used as a diagnostic instrument. However, more research is necessary in order to clarify the criteria and conditions to apply it. In addition, psychological indicators could complement the detection and prevention of this syndrome. The analyses of the interrelationships between physiological and psychological markers is claimed to better understand the nature and global implications of this syndrom

Indicadores psicológicos de sobreentrenamiento y agotamiento

El estado de agotamiento producido fundamentalmente por un sobreentrenamiento, aunque facilitado por otros estresores incluídos los extradeportivos, provoca una amplia síntomatología junto a un deterioro del rendimiento, que impiden a algunos deportistas mantener o superar sus marcas previas. Por ello, ha aumentado el número de investigaciones orientadas a la detección de indicadores que tracen de forma correcta el límite entre la adaptación al entrenamiento y el agotamiento. Los marcadores biológicos disponibles actualmente no proporcionan un criterio unánimemente aceptado para definir este límite, por lo que la investigación se ha orientado al uso de algunos indicadores psicológicos, que ofrecen resultados prometedores. Concretamente, en este trabajo se revisan los estudios que han utilizado instrumentos psicológicos (RPE, POMS y algunas escalas específicas) para la evaluación de los síntomas del sobreentrenamiento.An excessive training can prevent the maintenance or improvement of the previous sports performance. This drop in the performance is mainly due to the overtraining, and it is usually called overtraining syndrome, staleness or fatigue. Because of the negative effects of this state, recent research has focused on the boundary between adaptation or disadaptation to training. Biological and psychological markers have been used for detecting overtraining. Recently, several psychological ratings have been employed in this field. This paper critically reviews psychological tools used for detecting psychological disruption produced by erroneous training programmes. In concrete, we will analyse results obtained from the Rate of Perceived Exertion (RPE), the Profile of Mood States (POMS), complaint indexes, and symptoms and well-being scales

Personality and Hypothalamic–Pituitary–Adrenal Axis in Older Men and Women

Personality has been related to health and mortality risk, which has created interest in the biological pathways that could explain this relationship. Although a dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis has been associated with health outcomes and aging, few studies have explored the association between personality and HPA axis functioning in older adults. In addition, it has been suggested that sex could moderate the relationship between personality and HPA axis functioning. Thus, our aim was to analyze the relationship between the big five personality traits and the diurnal cortisol pattern in older adults, as well as sex differences in this relationship. To do so, 79 older people (40 men and 39 women) from 59 to 81 years old (M = 69.19, SD = 4.60) completed the NEO-Five-Factor Inventory (FFI) to measure neuroticism, conscientiousness, extraversion, openness, and agreeableness. Saliva samples were provided on three consecutive days (awakening; 15, 30, and 45 min post-awakening; and bedtime) in order to analyze the diurnal cortisol pattern and, specifically, two cortisol indexes: the cortisol awakening response (CAR) and the diurnal cortisol slope (DCS). Results showed that neuroticism and conscientiousness moderated the diurnal cortisol pattern. Thus, individuals with higher neuroticism and lower conscientiousness scores showed higher bedtime cortisol levels, suggesting a less healthy diurnal cortisol pattern. Regarding the cortisol indexes, higher neuroticism and lower conscientiousness were related to greater CAR and DCS. Sex moderated the association between extraversion and the DCS. Specifically, higher extraversion was related to a lower DCS only in women. Openness and agreeableness were not related to the diurnal cortisol pattern. In conclusion, our results show that in older adults, neuroticism is a vulnerability factor for HPA axis dysregulation, with possible adverse effects on health. By contrast, conscientiousness, and extraversion only in women, appear to be protective factors of HPA axis functioning, with potential beneficial effects on health

Acute psychosocial stress effects on memory performance : relevance of age and sex

In recent decades, there has been a growing interest in investigating the effects of chronic and acute stress on cognitive processes, especially memory performance. However, research focusing on acute stress effects has reported contradictory findings, probably due to the many factors that can moderate this relationship. In addition to factors related to the individual, such as sex and age, other factors, such as the type of memory assessed, can play a critical role in the direction of these effects. This review summarizes the main findings of our research group and others about the effects of acute psychosocial stress on memory performance in young and older people of both sexes, taking into account the type and phase of memory assessed. In our opinion, an approach that addresses individual factors and other factors related to the type of stressor and temporal relationship between exposure to the stressor and performance will contribute to better understanding the mechanisms underlying the complex relationship between acute stress and memory. Finally, some new directions for future studies on this research topic are suggested

Pairwise gene GO-based measures for biclustering of high-dimensional expression data

Background: Biclustering algorithms search for groups of genes that share the same behavior under a subset of samples in gene expression data. Nowadays, the biological knowledge available in public repositories can be used to drive these algorithms to find biclusters composed of groups of genes functionally coherent. On the other hand, a distance among genes can be defined according to their information stored in Gene Ontology (GO). Gene pairwise GO semantic similarity measures report a value for each pair of genes which establishes their functional similarity. A scatter search-based algorithm that optimizes a merit function that integrates GO information is studied in this paper. This merit function uses a term that addresses the information through a GO measure. Results: The effect of two possible different gene pairwise GO measures on the performance of the algorithm is analyzed. Firstly, three well known yeast datasets with approximately one thousand of genes are studied. Secondly, a group of human datasets related to clinical data of cancer is also explored by the algorithm. Most of these data are high-dimensional datasets composed of a huge number of genes. The resultant biclusters reveal groups of genes linked by a same functionality when the search procedure is driven by one of the proposed GO measures. Furthermore, a qualitative biological study of a group of biclusters show their relevance from a cancer disease perspective. Conclusions: It can be concluded that the integration of biological information improves the performance of the biclustering process. The two different GO measures studied show an improvement in the results obtained for the yeast dataset. However, if datasets are composed of a huge number of genes, only one of them really improves the algorithm performance. This second case constitutes a clear option to explore interesting datasets from a clinical point of view.Ministerio de Economía y Competitividad TIN2014-55894-C2-