The impact of early repeated pain experiences on stress responsiveness and emotionality at maturity in rats.

PubMed

Page, Gayle G; Blakely, Wendy P; Kim, Miyong

2005-01-01

The intensive care necessary for premature newborns is characterized by multiple procedures, many of which are painful. Given emerging evidence that such early pain during this time of high brain plasticity may affect long-term neurodevelopmental and social-emotional functioning, this study explored the impact of early repeated pain on emotionality and stress responsivity at maturity. From birth through postnatal day 7, Fischer 344 pups underwent either paw needle prick every day versus every other day or daily paw touch, or were left unperturbed. Each paw received the designated perturbation once per day. At maturity, some animals underwent emotionality testing: either a 4-day series of open field exposures or a single elevated plus-maze (EPM) exposure. The paw prick groups exhibited less open field habituation and occupied the EPM open arms more. Two weeks later, all animals were either subjected to forced swim or not. At 1h post-swim, animals underwent either blood withdrawal for plasma corticosterone (CS) levels and ex vivo natural killer cell activity (NKCA) or were injected intravenously with radiolabeled NK-sensitive syngeneic MADB106 tumor cells and assessed for lung tumor retention. Sex was a major factor in the manifestation of perturbation-related differences in the biologic outcomes. Whereas postnatal pain differentially affected baseline tumor retention between males and females, only males exhibited perturbation-related differences in swim stress-induced increases in tumor retention and CS. Finally, male-female differences were evident in CS, NKCA, and tumor responses to swim stress. These findings suggest that early pain affects neurodevelopmental function in the mature organism; however, these relationships are complicated by sex differences, the postnatal pain schedule, and the outcome measured.

Individual Differences in Biological Stress Responses Moderate the Contribution of Early Peer Victimization to Subsequent Depressive Symptoms

PubMed Central

Rudolph, Karen D.; Troop-Gordon, Wendy; Granger, Douglas A.

2011-01-01

Rationale Some children who are exposed to early peer victimization become depressed, whereas others are resilient. Understanding individual differences in responses to early adversity, such as victimization, is critical for developing both comprehensive theoretical models and effective interventions. Objectives This study examined whether individual differences in biological stress responses (i.e., activation of the hypothalamic-pituitary-adrenal axis and autonomic nervous system) moderated the contribution of peer victimization to depressive symptoms across a one-year period. Methods Children (N = 132; M age = 9.46 years, SD = .33) completed measures of peer victimization and depressive symptoms, and rated their ruminative responses (i.e., persistent thoughts about negative task-related emotion and experiences) to a laboratory-based social challenge task involving two conflict-of-interests situations with an unfamiliar peer. Children’s saliva was collected prior to, and following, participation in the task, and was later assayed for cortisol and alpha amylase [sAA]. Results Victimization interacted with levels of cortisol measured in anticipation of the task to predict task-related rumination and depressive symptoms one year later, adjusting for initial symptoms. Specifically, victimization served as a risk factor for rumination and depressive symptoms in children with heightened but not dampened anticipatory cortisol; yet, heightened anticipatory cortisol was protective against rumination and depressive symptoms in low-victimized children. Victimization also predicted subsequent depressive symptoms in girls with high sAA reactivity across the task. Conclusions This study advances contemporary theory and research by implicating individual variation in biological stress responses as one determinant of sensitivity to the mental health effects of early adversity. PMID:20505926

Impact of chronic maternal stress during early gestation on maternal-fetal stress transfer and fetal stress sensitivity in sheep.

PubMed

Dreiling, Michelle; Schiffner, Rene; Bischoff, Sabine; Rupprecht, Sven; Kroegel, Nasim; Schubert, Harald; Witte, Otto W; Schwab, Matthias; Rakers, Florian

2018-01-01

Acute stress-induced reduction of uterine blood flow (UBF) is an indirect mechanism of maternal-fetal stress transfer during late gestation. Effects of chronic psychosocial maternal stress (CMS) during early gestation, as may be experienced by many working women, on this stress signaling mechanism are unclear. We hypothesized that CMS in sheep during early gestation augments later acute stress-induced decreases of UBF, and aggravates the fetal hormonal, cardiovascular, and metabolic stress responses during later development. Six pregnant ewes underwent repeated isolation stress (CMS) between 30 and 100 days of gestation (dGA, term: 150 dGA) and seven pregnant ewes served as controls. At 110 dGA, ewes were chronically instrumented and underwent acute isolation stress. The acute stress decreased UBF by 19% in both the CMS and control groups (p < .05), but this was prolonged in CMS versus control ewes (74 vs. 30 min, p < .05). CMS increased fetal circulating baseline and stress-induced cortisol and norepinephrine concentrations indicating a hyperactive hypothalamus-pituitary-adrenal (HPA)-axis and sympathetic-adrenal-medullary system. Increased fetal norepinephrine is endogenous as maternal catecholamines do not cross the placenta. Cortisol in the control but not in the CMS fetuses was correlated with maternal cortisol blood concentrations; these findings indicate: (1) no increased maternal-fetal cortisol transfer with CMS, (2) cortisol production in CMS fetuses when the HPA-axis is normally inactive, due to early maturation of the fetal HPA-axis. CMS fetuses were better oxygenated, without shift towards acidosis compared to the controls, potentially reflecting adaptation to repeated stress. Hence, CMS enhances maternal-fetal stress transfer by prolonged reduction in UBF and increased fetal HPA responsiveness.

ATM-dependent E2F1 accumulation in the nucleolus is an indicator of ribosomal stress in early response to DNA damage

PubMed Central

Jin, Ya-Qiong; An, Guo-Shun; Ni, Ju-Hua; Li, Shu-Yan; Jia, Hong-Ti

2014-01-01

The nucleolus plays a major role in ribosome biogenesis. Most genotoxic agents disrupt nucleolar structure and function, which results in the stabilization/activation of p53, inducing cell cycle arrest or apoptosis. Likewise, transcription factor E2F1 as a DNA damage responsive protein also plays roles in cell cycle arrest, DNA repair, or apoptosis in response to DNA damage through transcriptional response and protein–protein interaction. Furthermore, E2F1 is known to be involved in regulating rRNA transcription. However, how E2F1 displays in coordinating DNA damage and nucleolar stress is unclear. In this study, we demonstrate that ATM-dependent E2F1 accumulation in the nucleolus is a characteristic feature of nucleolar stress in early response to DNA damage. We found that at the early stage of DNA damage, E2F1 accumulation in the nucleolus was an ATM-dependent and a common event in p53-suficient and -deficient cells. Increased nucleolar E2F1 was sequestered by the nucleolar protein p14ARF, which repressed E2F1-dependent rRNA transcription initiation, and was coupled with S phase. Our data indicate that early accumulation of E2F1 in the nucleolus is an indicator for nucleolar stress and a component of ATM pathway, which presumably buffers elevation of E2F1 in the nucleoplasm and coordinates the diversifying mechanisms of E2F1 acts in cell cycle progression and apoptosis in early response to DNA damage. PMID:24675884

ATM-dependent E2F1 accumulation in the nucleolus is an indicator of ribosomal stress in early response to DNA damage.

PubMed

Jin, Ya-Qiong; An, Guo-Shun; Ni, Ju-Hua; Li, Shu-Yan; Jia, Hong-Ti

2014-01-01

The nucleolus plays a major role in ribosome biogenesis. Most genotoxic agents disrupt nucleolar structure and function, which results in the stabilization/activation of p53, inducing cell cycle arrest or apoptosis. Likewise, transcription factor E2F1 as a DNA damage responsive protein also plays roles in cell cycle arrest, DNA repair, or apoptosis in response to DNA damage through transcriptional response and protein-protein interaction. Furthermore, E2F1 is known to be involved in regulating rRNA transcription. However, how E2F1 displays in coordinating DNA damage and nucleolar stress is unclear. In this study, we demonstrate that ATM-dependent E2F1 accumulation in the nucleolus is a characteristic feature of nucleolar stress in early response to DNA damage. We found that at the early stage of DNA damage, E2F1 accumulation in the nucleolus was an ATM-dependent and a common event in p53-suficient and -deficient cells. Increased nucleolar E2F1 was sequestered by the nucleolar protein p14ARF, which repressed E2F1-dependent rRNA transcription initiation, and was coupled with S phase. Our data indicate that early accumulation of E2F1 in the nucleolus is an indicator for nucleolar stress and a component of ATM pathway, which presumably buffers elevation of E2F1 in the nucleoplasm and coordinates the diversifying mechanisms of E2F1 acts in cell cycle progression and apoptosis in early response to DNA damage.

Early Social Deprivation and the Social Buffering of Cortisol Stress Responses in Late Childhood: An Experimental Study

ERIC Educational Resources Information Center

Hostinar, Camelia E.; Johnson, Anna E.; Gunnar, Megan R.

2015-01-01

The goal of the present study was to investigate the role of early social deprivation in shaping the effectiveness of parent support to alleviate hypothalamic-pituitary-adrenal (HPA)-axis-stress responses of children (ages 8.9-11, M = 9.83 years, SD = 0.55). The sample was equally divided between children who had been adopted internationally from…

Responses to Interpersonal Stress: Normative Changes Across Childhood and the Impact of Peer Victimization

PubMed Central

Troop-Gordon, Wendy; Sugimura, Niwako; Rudolph, Karen D.

2016-01-01

This research examined the development of stress responses across 2nd to 6th grades and whether exposure to peer victimization alters stress response trajectories. Youth (338 girls; 298 boys; M age = 7.97 years, SD = .37) reported on stress responses; teachers and youth reported on peer victimization. Latent growth curve modeling revealed an increase in effortful engagement responses and a decrease in disengagement and involuntary engagement responses during this period. Peer victimization disrupted these normative trajectories, resulting in less effortful engagement and more effortful disengagement and involuntary stress responses in early adolescence. These findings suggest that early peer victimization sensitizes youth to stress by interfering with the development of effective coping and fostering maladaptive stress responses. PMID:27709602

The Long-term Impact of Early Life Pain On Adult Responses to Anxiety and Stress: Historical Perspectives and Empirical Evidence

PubMed Central

Victoria, Nicole C.; Murphy, Anne Z.

2016-01-01

Approximately 1 in 6 infants are born prematurely each year. Typically, these infants spend 25 days in the Neonatal Intensive Care Unit (NICU) where they experience 10–18 painful and inflammatory procedures each day. Remarkably, pre-emptive analgesics and/or anesthesia are administered less than 25% of the time. Unalleviated pain during the perinatal period is associated with permanent decreases in pain sensitivity, blunted cortisol responses and high rates of neuropsychiatric disorders. To date, the mechanism(s) by which these long-term changes in stress and pain behavior occur, and whether such alterations can be prevented by appropriate analgesia at the time of insult, remains unclear. Work in our lab using a rodent model of early life pain suggests that inflammatory pain experienced on the day of birth blunts adult responses to stress- and pain-provoking stimuli, and dysregulates the hypothalamic pituitary adrenal (HPA) axis in part through a permanent upregulation in central endogenous opioid tone. This review focuses on the long-term impact of neonatal inflammatory pain on adult anxiety- and stress-related responses, and underlying neuroanatomical changes in the context of endogenous pain control and the HPA axis. These two systems are in a state of exaggerated developmental plasticity early in postnatal life, and work in concert to respond to noxious or aversive stimuli. We present empirical evidence from animal and clinical studies, and discuss historical perspectives underlying the lack of analgesia/anesthetic use for early life pain in the modern NICU. PMID:26210872

Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response

PubMed Central

Brosschot, Jos F.; Thayer, Julian F.

2018-01-01

Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always “on” but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS) states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories. PMID:29518937

Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response.

PubMed

Brosschot, Jos F; Verkuil, Bart; Thayer, Julian F

2018-03-07

Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always "on" but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS) states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

Early-Life Stress Affects Stress-Related Prefrontal Dopamine Activity in Healthy Adults, but Not in Individuals with Psychotic Disorder

PubMed Central

Kasanova, Zuzana; Hernaus, Dennis; Vaessen, Thomas; van Amelsvoort, Thérèse; Winz, Oliver; Heinzel, Alexander; Pruessner, Jens; Mottaghy, Felix M.

2016-01-01

Early life stress may have a lasting impact on the developmental programming of the dopamine (DA) system implicated in psychosis. Early adversity could promote resilience by calibrating the prefrontal stress-regulatory dopaminergic neurotransmission to improve the individual’s fit with the predicted stressful environment. Aberrant reactivity to such match between proximal and distal environments may, however, enhance psychosis disease risk. We explored the combined effects of childhood adversity and adult stress by exposing 12 unmedicated individuals with a diagnosis of non-affective psychotic disorder (NAPD) and 12 healthy controls (HC) to psychosocial stress during an [18F]fallypride positron emission tomography. Childhood trauma divided into early (ages 0–11 years) and late (12–18 years) was assessed retrospectively using a questionnaire. A significant group x childhood trauma interaction on the spatial extent of stress-related [18F]fallypride displacement was observed in the mPFC for early (b = -8.45, t(1,23) = -3.35, p = .004) and late childhood trauma (b = -7.86, t(1,23) = -2.48, p = .023). In healthy individuals, the spatial extent of mPFC DA activity under acute psychosocial stress was positively associated with the severity of early (b = 7.23, t(11) = 3.06, p = .016) as well as late childhood trauma (b = -7.86, t(1,23) = -2.48, p = .023). Additionally, a trend-level main effect of early childhood trauma on subjective stress response emerged within this group (b = -.7, t(11) = -2, p = .07), where higher early trauma correlated with lower subjective stress response to the task. In the NAPD group, childhood trauma was not associated with the spatial extent of the tracer displacement in mPFC (b = -1.22, t(11) = -0.67), nor was there a main effect of trauma on the subjective perception of stress within this group (b = .004, t(11) = .01, p = .99). These findings reveal a potential mechanism of neuroadaptation of prefrontal DA transmission to early life

Multi-Wave Prospective Examination of the Stress-Reactivity Extension of Response Styles Theory of Depression in High-Risk Children and Early Adolescents

ERIC Educational Resources Information Center

Abela, John R. Z.; Hankin, Benjamin L.; Sheshko, Dana M.; Fishman, Michael B.; Stolow, Darren

2012-01-01

The current study tested the stress-reactivity extension of response styles theory of depression (Nolen-Hoeksema "Journal of Abnormal Psychology" 100:569-582, 1991) in a sample of high-risk children and early adolescents from a vulnerability-stress perspective using a multi-wave longitudinal design. In addition, we examined whether obtained…

Maternal Influences on Youth Responses to Peer Stress

ERIC Educational Resources Information Center

Abaied, Jamie L.; Rudolph, Karen D.

2011-01-01

Understanding how youths develop particular styles of responding to stress is critical for promoting effective coping. This research examined the prospective, interactive contribution of maternal socialization of coping and peer stress to youth responses to peer stress. A sample of 144 early adolescents (mean age = 12.44 years, SD = 1.22) and…

Early transcriptional changes in the reef-building coral Acropora aspera in response to thermal and nutrient stress.

PubMed

Rosic, Nedeljka; Kaniewska, Paulina; Chan, Chon-Kit Kenneth; Ling, Edmund Yew Siang; Edwards, David; Dove, Sophie; Hoegh-Guldberg, Ove

2014-12-02

Changes to the environment as a result of human activities can result in a range of impacts on reef building corals that include coral bleaching (reduced concentrations of algal symbionts), decreased coral growth and calcification, and increased incidence of diseases and mortality. Understanding how elevated temperatures and nutrient concentration affect early transcriptional changes in corals and their algal endosymbionts is critically important for evaluating the responses of coral reefs to global changes happening in the environment. Here, we investigated the expression of genes in colonies of the reef-building coral Acropora aspera exposed to short-term sub-lethal levels of thermal (+6°C) and nutrient stress (ammonium-enrichment: 20 μM). The RNA-Seq data provided hundreds of differentially expressed genes (DEGs) corresponding to various stress regimes, with 115 up- and 78 down-regulated genes common to all stress regimes. A list of DEGs included up-regulated coral genes like cytochrome c oxidase and NADH-ubiquinone oxidoreductase and up-regulated photosynthetic genes of algal origin, whereas coral GFP-like fluorescent chromoprotein and sodium/potassium-transporting ATPase showed reduced transcript levels. Taxonomic analyses of the coral holobiont disclosed the dominant presence of transcripts from coral (~70%) and Symbiodinium (~10-12%), as well as ~15-20% of unknown sequences which lacked sequence identity to known genes. Gene ontology analyses revealed enriched pathways, which led to changes in the dynamics of protein networks affecting growth, cellular processes, and energy requirement. In corals with preserved symbiont physiological performance (based on Fv/Fm, photo-pigment and symbiont density), transcriptomic changes and DEGs provided important insight into early stages of the stress response in the coral holobiont. Although there were no signs of coral bleaching after exposure to short-term thermal and nutrient stress conditions, we managed to detect

Impact of early life stress on the pathogenesis of mental disorders: relation to brain oxidative stress.

PubMed

Schiavone, Stefania; Colaianna, Marilena; Curtis, Logos

2015-01-01

Stress is an inevitable part of human life and it is experienced even before birth. Stress to some extent could be considered normal and even necessary for the survival and the regular psychological development during childhood or adolescence. However, exposure to prolonged stress could become harmful and strongly impact mental health increasing the risk of developing psychiatric disorders. Recent studies have attempted to clarify how the human central nervous system (CNS) reacts to early life stress, focusing mainly on neurobiological modifications. Oxidative stress, defined as a disequilibrium between the oxidant generation and the antioxidant response, has been recently described as a candidate for most of the observed modifications. In this review, we will discuss how prolonged stressful events during childhood or adolescence (such as early maternal separation, parental divorce, physical violence, sexual or psychological abuses, or exposure to war events) can lead to increased oxidative stress in the CNS and enhance the risk to develop psychiatric diseases such as anxiety, depression, drug abuse or psychosis. Defining the sources of oxidative stress following exposure to early life stress might open new beneficial insights in therapeutic approaches to these mental disorders.

Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways.

PubMed

Dues, Dylan J; Andrews, Emily K; Schaar, Claire E; Bergsma, Alexis L; Senchuk, Megan M; Van Raamsdonk, Jeremy M

2016-04-01

In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage.

Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

PubMed Central

Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

2016-01-01

In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage. PMID:27053445

The long-term impact of early life pain on adult responses to anxiety and stress: Historical perspectives and empirical evidence.

PubMed

Victoria, Nicole C; Murphy, Anne Z

2016-01-01

Approximately 1 in 6 infants are born prematurely each year. Typically, these infants spend 25 days in the Neonatal Intensive Care Unit (NICU) where they experience 10-18 painful and inflammatory procedures each day. Remarkably, pre-emptive analgesics and/or anesthesia are administered less than 25% of the time. Unalleviated pain during the perinatal period is associated with permanent decreases in pain sensitivity, blunted cortisol responses and high rates of neuropsychiatric disorders. To date, the mechanism(s) by which these long-term changes in stress and pain behavior occur, and whether such alterations can be prevented by appropriate analgesia at the time of insult, remains unclear. Work in our lab using a rodent model of early life pain suggests that inflammatory pain experienced on the day of birth blunts adult responses to stress- and pain-provoking stimuli, and dysregulates the hypothalamic pituitary adrenal (HPA) axis in part through a permanent upregulation in central endogenous opioid tone. This review focuses on the long-term impact of neonatal inflammatory pain on adult anxiety- and stress-related responses, and underlying neuroanatomical changes in the context of endogenous pain control and the HPA axis. These two systems are in a state of exaggerated developmental plasticity early in postnatal life, and work in concert to respond to noxious or aversive stimuli. We present empirical evidence from animal and clinical studies, and discuss historical perspectives underlying the lack of analgesia/anesthetic use for early life pain in the modern NICU. Copyright © 2015 Elsevier Inc. All rights reserved.

Responses to Interpersonal Stress: Normative Changes Across Childhood and the Impact of Peer Victimization.

PubMed

Troop-Gordon, Wendy; Sugimura, Niwako; Rudolph, Karen D

2017-03-01

This research examined the development of stress responses across second to sixth grades and whether exposure to peer victimization alters stress response trajectories. Youth (338 girls; 298 boys; M age  = 7.97 years, SD = .37) reported on stress responses; teachers and youth reported on peer victimization. Latent growth curve modeling revealed an increase in effortful engagement responses and a decrease in disengagement and involuntary engagement responses during this period. Peer victimization disrupted these normative trajectories, resulting in less effortful engagement and more effortful disengagement and involuntary stress responses in early adolescence. These findings suggest that early peer victimization sensitizes youth to stress by interfering with the development of effective coping and fostering maladaptive stress responses. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Early Social Deprivation and the Social Buffering of Cortisol Stress Responses in Late Childhood: An Experimental Study

PubMed Central

Hostinar, Camelia E.; Johnson, Anna E.; Gunnar, Megan R.

2015-01-01

The goal of the present study was to investigate the role of early social deprivation in shaping the effectiveness of parent support to alleviate hypothalamic-pituitary-adrenal (HPA) axis stress responses of children (ages 8.9–11, M = 9.83 years, SD = .55). The sample was equally divided between children who had been adopted internationally from orphanage care by age 5 (N = 40) and an age- and gender-matched group of non-adopted children (N = 40). On average, internationally adopted children were invited to the laboratory 7.6 years post-adoption (SD = 1.45). We experimentally manipulated the provision of parent support during the 5-minute speech preparation period before a modified Trier Social Stress Test (TSST) and examined its effect on levels of salivary cortisol secreted in response to this laboratory stressor. All participants were randomly assigned to receive support from their parent or a stranger. Analyses revealed a significant interaction of support condition and group such that parent support significantly dampened the cortisol stress response in non-adopted children compared to support from a stranger, whereas the cortisol response curves of post-institutionalized children did not differ between the parent and stranger support conditions. Cortisol reactivity for PI children in both conditions was lower than that of non-adopted children in the stranger support condition. Social deprivation during the first few years of life may shape neurobehavioral development in ways that reduce selective responses to caregivers versus strangers. PMID:26322485

Attentional avoidance of fearful facial expressions following early life stress is associated with impaired social functioning.

PubMed

Humphreys, Kathryn L; Kircanski, Katharina; Colich, Natalie L; Gotlib, Ian H

2016-10-01

Early life stress is associated with poorer social functioning. Attentional biases in response to threat-related cues, linked to both early experience and psychopathology, may explain this association. To date, however, no study has examined attentional biases to fearful facial expressions as a function of early life stress or examined these biases as a potential mediator of the relation between early life stress and social problems. In a sample of 154 children (ages 9-13 years) we examined the associations among interpersonal early life stressors (i.e., birth through age 6 years), attentional biases to emotional facial expressions using a dot-probe task, and social functioning on the Child Behavior Checklist. High levels of early life stress were associated with both greater levels of social problems and an attentional bias away from fearful facial expressions, even after accounting for stressors occurring in later childhood. No biases were found for happy or sad facial expressions as a function of early life stress. Finally, attentional biases to fearful faces mediated the association between early life stress and social problems. Attentional avoidance of fearful facial expressions, evidenced by a bias away from these stimuli, may be a developmental response to early adversity and link the experience of early life stress to poorer social functioning. © 2016 Association for Child and Adolescent Mental Health.

Psychoneuroimmunology of Early-Life Stress: The Hidden Wounds of Childhood Trauma?

PubMed Central

Danese, Andrea; J Lewis, Stephanie

2017-01-01

The brain and the immune system are not fully formed at birth, but rather continue to mature in response to the postnatal environment. The two-way interaction between the brain and the immune system makes it possible for childhood psychosocial stressors to affect immune system development, which in turn can affect brain development and its long-term functioning. Drawing from experimental animal models and observational human studies, we propose that the psychoneuroimmunology of early-life stress can offer an innovative framework to understand and treat psychopathology linked to childhood trauma. Early-life stress predicts later inflammation, and there are striking analogies between the neurobiological correlates of early-life stress and of inflammation. Furthermore, there are overlapping trans-diagnostic patterns of association of childhood trauma and inflammation with clinical outcomes. These findings suggest new strategies to remediate the effect of childhood trauma before the onset of clinical symptoms, such as anti-inflammatory interventions and potentiation of adaptive immunity. Similar strategies might be used to ameliorate the unfavorable treatment response described in psychiatric patients with a history of childhood trauma. PMID:27629365

Global transcriptome analysis of grapevine (Vitis vinifera L.) leaves under salt stress reveals differential response at early and late stages of stress in table grape cv. Thompson Seedless.

PubMed

Upadhyay, Anuradha; Gaonkar, Tulsi; Upadhyay, Ajay Kumar; Jogaiah, Satisha; Shinde, Manisha P; Kadoo, Narendra Y; Gupta, Vidya S

2018-05-31

Among the different abiotic stresses, salt stress has a significant effect on the growth and yield of grapevine (Vitis vinifera L.). In this study, we employed RNA sequence based transcriptome analysis to study salinity stress response in grape variety Thompson Seedless. Salt stress adversely affected the growth related and physiological parameters and the effect on physiological parameters was significant within 10 days of stress imposition. A total of 343 genes were differentially expressed in response to salt stress. Among the differentially expressed genes (DEGs) only 42 genes were common at early and late stages of stress. The gene enrichment analysis revealed that GO terms related to transcription factors were over-represented. Among the DEGs, 52 were transcription factors belonging to WRKY, EREB, MYB, NAC and bHLH families. Salt stress significantly affected several pathways like metabolic pathways, biosynthesis of secondary metabolites, membrane transport development related pathways etc. 343 DEGs were distributed on all the 19 chromosomes, however clustered regions of DEGs were present on chromosomes 2, 5, 6 and 12 suggesting probable QTLs for imparting tolerance to salt and other abiotic stresses. Real-time PCR of selected genes in control and treated samples of grafted and own root vines demonstrated that rootstock influenced expression of salt stress responsive genes. Microsatellite regions were identified in ten selected salt responsive genes and highly polymorphic markers were identified using fifteen grape genotypes. This information will be useful for the identification of key genes involved in salt stress tolerance in grape. The identified DEGs could also be useful for genome wide analysis for the identification of polymorphic markers for their subsequent use in molecular breeding for developing salt tolerant grape genotypes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Leaf Responses to Mild Drought Stress in Natural Variants of Arabidopsis1[OPEN

PubMed Central

Clauw, Pieter; Coppens, Frederik; De Beuf, Kristof; Dhondt, Stijn; Van Daele, Twiggy; Maleux, Katrien; Storme, Veronique; Clement, Lieven; Gonzalez, Nathalie; Inzé, Dirk

2015-01-01

Although the response of plants exposed to severe drought stress has been studied extensively, little is known about how plants adapt their growth under mild drought stress conditions. Here, we analyzed the leaf and rosette growth response of six Arabidopsis (Arabidopsis thaliana) accessions originating from different geographic regions when exposed to mild drought stress. The automated phenotyping platform WIWAM was used to impose stress early during leaf development, when the third leaf emerges from the shoot apical meristem. Analysis of growth-related phenotypes showed differences in leaf development between the accessions. In all six accessions, mild drought stress reduced both leaf pavement cell area and number without affecting the stomatal index. Genome-wide transcriptome analysis (using RNA sequencing) of early developing leaf tissue identified 354 genes differentially expressed under mild drought stress in the six accessions. Our results indicate the existence of a robust response over different genetic backgrounds to mild drought stress in developing leaves. The processes involved in the overall mild drought stress response comprised abscisic acid signaling, proline metabolism, and cell wall adjustments. In addition to these known severe drought-related responses, 87 genes were found to be specific for the response of young developing leaves to mild drought stress. PMID:25604532

High novelty-seeking rats are resilient to negative physiological effects of the early life stress.

PubMed

Clinton, Sarah M; Watson, Stanley J; Akil, Huda

2014-01-01

Exposure to early life stress dramatically impacts adult behavior, physiology, and neuroendocrine function. Using rats bred for novelty-seeking differences and known to display divergent anxiety, depression, and stress vulnerability, we examined the interaction between early life adversity and genetic predisposition for high- versus low-emotional reactivity. Thus, bred Low Novelty Responder (bLR) rats, which naturally exhibit high anxiety- and depression-like behavior, and bred High Novelty Responder (bHR) rats, which show low anxiety/depression together with elevated aggression, impulsivity, and addictive behavior, were subjected to daily 3 h maternal separation (MS) stress postnatal days 1-14. We hypothesized that MS stress would differentially impact adult bHR/bLR behavior, physiology (stress-induced defecation), and neuroendocrine reactivity. While MS stress did not impact bHR and bLR anxiety-like behavior in the open field test and elevated plus maze, it exacerbated bLRs' already high physiological response to stress - stress-induced defecation. In both tests, MS bLR adult offspring showed exaggerated stress-induced defecation compared to bLR controls while bHR offspring were unaffected. MS also selectively impacted bLRs' (but not bHRs') neuroendocrine stress reactivity, producing an exaggerated corticosterone acute stress response in MS bLR versus control bLR rats. These findings highlight how genetic predisposition shapes individuals' response to early life stress. Future work will explore neural mechanisms underlying the distinct behavioral and neuroendocrine consequences of MS in bHR/bLR animals.

Early life thermal stress: Impact on future thermotolerance, stress response, behavior, and intestinal morphology in piglets exposed to a heat stress challenge during simulated transport

USDA-ARS?s Scientific Manuscript database

Study objectives were to evaluate the impact of early life thermal stress (ELTS) on thermoregulation, stress, and intestinal health of piglets subjected to a future heat stress (HS) challenge during simulated transport. Approximately 7 d after farrowing, 12 first parity gilts and their litters were ...

Habitat odor can alleviate innate stress responses in mice.

PubMed

Matsukawa, Mutsumi; Imada, Masato; Aizawa, Shin; Sato, Takaaki

2016-01-15

Predatory odors, which can induce innate fear and stress responses in prey species, are frequently used in the development of animal models for several psychiatric diseases including post-traumatic stress disorder (PTSD) following a life-threatening event. We have previously shown that odors can be divided into at least three types; odors that act as (1) innate stressors, (2) as innate relaxants, or (3) have no innate effects on stress responses. Here, we attempted to verify whether an artificial odor, which had no innate effect on predatory odor-induced stress, could alleviate stress if experienced in early life as a habitat odor. In the current study, we demonstrated that the innate responses were changed to counteract stress following a postnatal experience. Moreover, we suggest that inhibitory circuits involved in stress-related neuronal networks and the concentrations of norepinephrine in the hippocampus may be crucial in alleviating stress induced by the predatory odor. Overall, these findings may be important for understanding the mechanisms involved in differential odor responses and also for the development of pharmacotherapeutic interventions that can alleviate stress in illnesses like PTSD. Copyright © 2015 Elsevier B.V. All rights reserved.

Acquisition of English word stress patterns in early and late bilinguals

NASA Astrophysics Data System (ADS)

Guion, Susan G.

2004-05-01

Given early acquisition of prosodic knowledge as demonstrated by infants' sensitivity to native language accentual patterns, the question of whether learners can acquire new prosodic patterns across the life span arises. Acquisition of English stress by early and late Spanish-English and Korean-English bilinguals was investigated. In a production task, two-syllable nonwords were produced in noun and verb sentence frames. In a perception task, preference for first or last syllable stress on the nonwords was indicated. Also, real words that were phonologically similar to the nonwords were collected. Logistic regression analyses and ANOVAs were conducted to determine the effect of three factors (syllable structure, lexical class, and stress patterns of phonologically similar words) on the production and perception responses. In all three groups, stress patterns of phonologically similar real words predicted stress on nonwords. For the two other factors, early bilinguals patterned similarly to the native-English participants. Late Spanish-English bilinguals demonstrated less learning of stress patterns based on syllabic structure, and late Korean-English bilinguals demonstrated less learning of stress patterns based on lexical class than native-English speakers. Thus, compared to native speakers, late bilinguals' ability to abstract stress patterns is reduced and affected by the first language. [Work supported by NIH.

Systems biology meets stress ecology: linking molecular and organismal stress responses in Daphnia magna

PubMed Central

Heckmann, Lars-Henrik; Sibly, Richard M; Connon, Richard; Hooper, Helen L; Hutchinson, Thomas H; Maund, Steve J; Hill, Christopher J; Bouetard, Anthony; Callaghan, Amanda

2008-01-01

Background Ibuprofen and other nonsteroidal anti-inflammatory drugs have been designed to interrupt eicosanoid metabolism in mammals, but little is known of how they affect nontarget organisms. Here we report a systems biology study that simultaneously describes the transcriptomic and phenotypic stress responses of the model crustacean Daphnia magna after exposure to ibuprofen. Results Our findings reveal intriguing similarities in the mode of action of ibuprofen between vertebrates and invertebrates, and they suggest that ibuprofen has a targeted impact on reproduction at the molecular, organismal, and population level in daphnids. Microarray expression and temporal real-time quantitative PCR profiles of key genes suggest early ibuprofen interruption of crustacean eicosanoid metabolism, which appears to disrupt signal transduction affecting juvenile hormone metabolism and oogenesis. Conclusion Combining molecular and organismal stress responses provides a guide to possible chronic consequences of environmental stress for population health. This could improve current environmental risk assessment by providing an early indication of the need for higher tier testing. Our study demonstrates the advantages of a systems approach to stress ecology, in which Daphnia will probably play a major role. PMID:18291039

Tissue-Specific Expression of DNA Methyltransferases Involved in Early-Life Nutritional Stress of Chicken, Gallus gallus

PubMed Central

Kang, Seong W.; Madkour, Mahmoud; Kuenzel, Wayne J.

2017-01-01

DNA methylation was reported as a possible stress-adaptation mechanism involved in the transcriptional regulation of stress responsive genes. Limited data are available on effects of psychological stress and early-life nutritional stress on DNA methylation regulators [DNMTs: DNA (cytosine-5)-methyltransferase 1 (DNMT1), DNMT1 associated protein (DMAP1), DNMT 3 alpha (DNMT3A) and beta (DNMT3B)] in avian species. The objectives of this study were to: (1) investigate changes in expression of DNMT1, DMAP1, DNMT3A, and DNMT3B following acute (AS) or chronic immobilization stress (CS); (2) test immediate effect of early-life nutritional stress [food deprivation (FD) for 12 h (12hFD) or 36 h (36hFD) at the post-hatching period] on expression of DNA methylation regulators and glucocorticoid receptor (GR), and the long-term effect of early-life nutritional stress at 6 weeks of age. Expression of DNMTs and plasma corticosterone (CORT) concentration decreased by CS compared to AS (p < 0.05), indicating differential roles of DNA methylation regulators in the stress response. Plasma CORT at 12hFD and 36hFD birds increased compared to control birds (12hF and 36hF), but there were no significant differences in plasma CORT of 12hFD and 36hFD birds at 6 weeks of age compared to 6 week controls. DNMT1, DMAP1, and DNMT3B expression in the anterior pituitary increased by 12hFD, but decreased at 36hFD compared to their controls (P < 0.05). In liver, DNMT1, DNMT3A, and DNMT3B expression decreased by 12hFD, however, no significant changes occurred at 36hFD. Expression of DMAP1, DNMT3A, and DNMT3B in anterior pituitary and DMAP1 and DNMT3A expression in liver at 6 weeks of age were higher in 36hFD stressed birds compared to controls as well as 12hFD stressed birds. Hepatic GR expression decreased by 12hFD and increased by 36hFD (p < 0.05). Expression patterns of GR in the liver of FD stress-induced birds persisted until 6 weeks of age, suggesting the possible lifelong involvement of liver

Inhibition of anandamide hydrolysis dampens the neuroendocrine response to stress in neonatal rats subjected to suboptimal rearing conditions.

PubMed

McLaughlin, Ryan Joseph; Verlezza, Silvanna; Gray, Jennifer Megan; Hill, Matthew Nicholas; Walker, Claire-Dominique

2016-01-01

Exposure to stress during early development can exert profound effects on the maturation of the neuroendocrine stress axis. The endocannabinoid (ECB) system has recently surfaced as a fundamental component of the neuroendocrine stress response; however, the effect of early-life stress on neonatal ECB signaling and the capacity to which ECB enhancement may modulate neonatal stress responses is relatively unknown. The present study assessed whether exposure to early-life stress in the form of limited access to nesting/bedding material (LB) from postnatal (PND) day 2 to 9 alters neuroendocrine activity and hypothalamic ECB content in neonatal rats challenged with a novel immobilization stressor. Furthermore, we examined whether inhibition of fatty acid amide hydrolase (FAAH), the enzyme responsible for the degradation of anandamide (AEA) affects neuroendocrine responses in PND10 pups as a function of rearing conditions. Neonatal rats showed a robust increase in corticosterone (CORT) and adrenocorticotropin hormone (ACTH) secretion in response to immobilization stress, which was significantly blunted in pups reared in LB conditions. Accordingly, LB pups exhibited reduced stress-induced Fos immunoreactivity in the paraventricular nucleus of the hypothalamus, with no significant differences in hypothalamic ECB content. Administration of the FAAH inhibitor URB597 (0.3 mg/kg, ip) 90 min prior to immobilization stress significantly dampened stress-induced CORT release, but only in pups reared in LB conditions. These results suggest that rearing in restricted bedding conditions dampens the neuroendocrine response to stress, while augmenting AEA mitigates stress-induced alterations in glucocorticoid secretion preferentially in pups subjected to early-life stress.

Analysis of Brassica oleracea early stage abiotic stress responses reveals tolerance in multiple crop types and for multiple sources of stress.

PubMed

Beacham, Andrew M; Hand, Paul; Pink, David Ac; Monaghan, James M

2017-12-01

Brassica oleracea includes a number of important crop types such as cabbage, cauliflower, broccoli and kale. Current climate conditions and weather patterns are causing significant losses in these crops, meaning that new cultivars with improved tolerance of one or more abiotic stress types must be sought. In this study, genetically fixed B. oleracea lines belonging to a Diversity Fixed Foundation Set (DFFS) were assayed for their response to seedling stage-imposed drought, flood, salinity, heat and cold stress. Significant (P ≤ 0.05) variation in stress tolerance response was found for each stress, for each of four measured variables (relative fresh weight, relative dry weight, relative leaf number and relative plant height). Lines tolerant to multiple stresses were found to belong to several different crop types. There was no overall correlation between the responses to the different stresses. Abiotic stress tolerance was identified in multiple B. oleracea crop types, with some lines exhibiting resistance to multiple stresses. For each stress, no one crop type appeared significantly more or less tolerant than others. The results are promising for the development of more environmentally robust lines of different B. oleracea crops by identifying tolerant material and highlighting the relationship between responses to different stresses. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Stress-related cortisol responsivity modulates prospective memory.

PubMed

Glienke, K; Piefke, M

2017-12-01

It is known that there is inter-individual variation in behavioural and physiological stress reactions to the same stressor. The present study aimed to examine the impact of cortisol responsivity on performance in a complex real life-like prospective memory (PM) paradigm by a re-analysis of data published previously, with a focus on the taxonomy of cognitive dimensions of PM. Twenty-one male subjects were stressed with the Socially Evaluated Cold Pressor Test (SECPT) before the planning of intentions. Another group of 20 males underwent a control procedure. Salivary cortisol was measured to assess the intensity of the biological stress response. Additionally, participants rated the subjective experience of stress on a 5-point rating scale. Stressed participants were post-hoc differentiated in high (n = 11) and low cortisol responders (n = 10). Cortisol niveau differed significantly between the two groups, whereas subjective stress ratings did not. PM performance of low cortisol responders was stable across time and the PM performance of controls declined. High cortisol responders showed a nominally weaker PM retrieval across the early trails and significantly improved only on the last trial. The data demonstrate for the first time that participants with a low cortisol responsivity may benefit from stress exposure before the planning phase of PM. PM performance of high cortisol responders shows a more inconsistent pattern, which may be interpreted in the sense of a recency effect in PM retrieval. Alternatively, high cortisol responses may have a deteriorating effect on PM retrieval, which disappeared on the last trials of the task as a result of the decrease of cortisol levels across time. Importantly, the data also demonstrate that the intensity of cortisol responses does not necessarily correspond to the intensity of the mental experience of stress. © 2017 British Society for Neuroendocrinology.

Changes in the Phosphoproteome and Metabolome Link Early Signaling Events to Rearrangement of Photosynthesis and Central Metabolism in Salinity and Oxidative Stress Response in Arabidopsis1

PubMed Central

Chen, Yanmei; Hoehenwarter, Wolfgang

2015-01-01

Salinity and oxidative stress are major factors affecting and limiting the productivity of agricultural crops. The molecular and biochemical processes governing the plant response to abiotic stress have often been researched in a reductionist manner. Here, we report a systemic approach combining metabolic labeling and phosphoproteomics to capture early signaling events with quantitative metabolome analysis and enzyme activity assays to determine the effects of salt and oxidative stress on plant physiology. K+ and Na+ transporters showed coordinated changes in their phosphorylation pattern, indicating the importance of dynamic ion homeostasis for adaptation to salt stress. Unique phosphorylation sites were found for Arabidopsis (Arabidopsis thaliana) SNF1 kinase homolog10 and 11, indicating their central roles in the stress-regulated responses. Seven Sucrose Non-fermenting1-Related Protein Kinase2 kinases showed varying levels of phosphorylation at multiple serine/threonine residues in their kinase domain upon stress, showing temporally distinct modulation of the various isoforms. Salinity and oxidative stress also lead to changes in protein phosphorylation of proteins central to photosynthesis, in particular the kinase State Transition Protein7 required for state transition and light-harvesting II complex proteins. Furthermore, stress-induced changes of the phosphorylation of enzymes of central metabolism were observed. The phosphorylation patterns of these proteins were concurrent with changes in enzyme activity. This was reflected by altered levels of metabolites, such as the sugars sucrose and fructose, glycolysis intermediates, and amino acids. Together, our study provides evidence for a link between early signaling in the salt and oxidative stress response that regulates the state transition of photosynthesis and the rearrangement of primary metabolism. PMID:26471895

Regulation of Adult Neurogenesis and Plasticity by (Early) Stress, Glucocorticoids, and Inflammation

PubMed Central

Lucassen, Paul J.; Oomen, Charlotte A.; Naninck, Eva F.G.; Fitzsimons, Carlos P.; van Dam, Anne-Marie; Czeh, Boldizsár; Korosi, Aniko

2015-01-01

Exposure to stress is one of the best-known negative regulators of adult neurogenesis (AN). We discuss changes in neurogenesis in relation to exposure to stress, glucocorticoid hormones, and inflammation, with a particular focus on early development and on lasting effects of stress. Although the effects of acute and mild stress on AN are generally brief and can be quickly overcome, chronic exposure or more severe forms of stress can induce longer lasting reductions in neurogenesis that can, however, in part, be overcome by subsequent exposure to exercise, drugs targeting the stress system, and some antidepressants. Exposure to stress, particularly during the sensitive period of early life, may (re)program brain plasticity, in particular, in the hippocampus. This may increase the risk to develop cognitive or anxiety symptoms, common to brain diseases like dementia and depression in which plasticity changes occur, and a normalization of neurogenesis may be required for a successful treatment response and recovery. PMID:26330520

Physiological and biochemical stress responses in grassland species are influenced by both early-season ozone exposure and interspecific competition.

PubMed

Scebba, Francesca; Canaccini, Francesca; Castagna, Antonella; Bender, Jürgen; Weigel, Hans-Joachim; Ranieri, Annamaria

2006-08-01

The effects of two-year early season ozone exposure on physiological and biochemical stress response were investigated in model plant communities. Achillea millefolium and Veronica chamaedrys target plants were grown in monocultures and in mixed cultures with Poa pratensis (phytometer) and exposed in open-top chambers over two years for five weeks to charcoal-filtered (CF) air plus 25 nl l(-1) O3 (control) and non-filtered (NF) air plus 50 nl l(-1) O3. Significant O3 effects were detected in different physiological and biochemical parameters, evidencing interspecific differences in metabolic stress responses and a strong influence of the competition factor. O3 induced strong oxidative effects in Achillea irrespective to the different growth modality. Veronica showed less O3-induced effects in monoculture than when grown in competition with the phytometer. Poa exhibited a different behaviour against O3 depending on the species in competition, showing an overall higher sensitivity to O3 when in mixture with Achillea.

Sexually Dimorphic Responses to Early Adversity: Implications for Affective Problems and Autism Spectrum Disorder

PubMed Central

Davis, Elysia Poggi; Pfaff, Donald

2014-01-01

During gestation, development proceeds at a pace that is unmatched by any other stage of the lifecycle. For these reason the human fetus is particularly susceptible not only to organizing influences, but also to pathogenic disorganizing influences. Growing evidence suggests that exposure to prenatal adversity leads to neurological changes that underlie lifetime risks for mental illness. Beginning early in gestation, males and females show differential developmental trajectories and responses to stress. It is likely that sex-dependent organization of neural circuits during the fetal period influences differential vulnerability to mental health problems. We consider in this review evidence that sexually dimorphic responses to early life stress are linked to two developmental disorders: affective problems (greater female prevalence) and autism spectrum disorder (greater male prevalence). Recent prospective studies illustrating the neurodevelopmental consequences of fetal exposure to stress and stress hormones for males and females are considered here. Plausible biological mechanisms including the role of the sexually differentiated placenta are discussed. We consider in this review evidence that sexually dimorphic responses to early life stress are linked to two sets of developmental disorders: affective problems (greater female prevalence) and autism spectrum disorders (greater male prevalence). PMID:25038479

Evidence establishing a link between prenatal and early-life stress and asthma development.

PubMed

Rosa, Maria José; Lee, Alison G; Wright, Rosalind J

2018-04-01

The objective of this review is to provide an update on our evolving understanding of the effects of stress in pregnancy and during early development on the onset of asthma-related phenotypes across childhood, adolescence, and into early adulthood. Accumulating evidence over the past 2 decades has established that prenatal and early-life psychological stress and stress correlates (e.g., maternal anxiety or depression) increase the risk for childhood respiratory disorders. Recent systematic reviews and meta-analyses including numerous prospective epidemiological and case-control studies substantiate a significant effect of prenatal stress and stress in early childhood on the development of wheeze, asthma, and other atopic-related disorders (eczema and allergic rhinitis), with many studies showing an exposure-response relationship. Offspring of both sexes are susceptible to perinatal stress, but effects differ. The impact of stress on child wheeze/asthma can also be modified by exposure timing. Moreover, coexposure to prenatal stress can enhance the effect of chemical stressors, such as prenatal traffic-related air pollution, on childhood respiratory disease risk. Understanding complex interactions among exposure dose, timing, child sex, and concurrent environmental exposures promises to more fully characterize stress effects and identify susceptible subgroups. Although the link between perinatal stress and childhood asthma-related phenotypes is now well established, pathways by which stress predisposes children to chronic respiratory disorders are not as well delineated. Mechanisms central to the pathophysiology of wheeze/asthma and lung growth and development overlap and involve a cascade of events that include disrupted immune, neuroendocrine, and autonomic function as well as oxidative stress. Altered homeostatic functioning of these integrated systems during development can enhance vulnerability to asthma and altered lung development. Mechanistic studies that

Analgesia for early-life pain prevents deficits in adult anxiety and stress in rats.

PubMed

Victoria, Nicole C; Karom, Mary C; Murphy, Anne Z

2015-01-01

Previous studies in rats have established that inflammatory pain experienced on the day of birth (P0) decreases sensitivity to acute noxious, anxiety- and stress-provoking stimuli. However, to date, the impact of early-life pain on adult responses to chronic stress is not known. Further, the ability of morphine, administered at the time of injury, to mitigate changes in adult behavioral and hormonal responses to acute or chronic stressors has not been examined. P0 male and female Sprague-Dawley rat pups were given an intraplantar injection of 1% carrageenan or handled in an identical manner in the presence or absence of morphine. As adults, rats that experienced early-life pain displayed decreased sensitivity to acute stressors, as indicated by increased time in the inner area of the Open Field, and increased latency to immobility and decreased time immobile in the Forced Swim Test (FST). An accelerated return of corticosterone to baseline was also observed. Morphine administration at the time of injury completely reversed this 'hyporesponsive' phenotype. By contrast, following 7 days of chronic variable stress, injured animals displayed a 'hyperresponsive' phenotype in that they initiated immobility and spent significantly more time immobile in the FST than controls. Responses to chronic stress were also rescued in animals that received morphine at the time of injury. These data suggest that analgesia for early-life pain prevents adult hyposensitivity to acute anxiety- and stress-provoking stimuli and increased vulnerability to chronic stress, and have important clinical implications for the management of pain in infants. © 2014 S. Karger AG, Basel.

Psychometric Evaluation of the Ford Insomnia Response to Stress Test (FIRST) in Early Pregnancy.

PubMed

Gelaye, Bizu; Zhong, Qiu-Yue; Barrios, Yasmin V; Redline, Susan; Drake, Christopher L; Williams, Michelle A

2016-04-15

To evaluate the construct validity and factor structure of the Spanish-language version of the Ford Insomnia Response to Stress Test questionnaire (FIRST-S) when used in early pregnancy. A cohort of 647 women were interviewed at ≤ 16 weeks of gestation to collect information regarding lifestyle, demographic, and sleep characteristics. The factorial structure of the FIRST-S was tested through exploratory and confirmatory factor analyses (EFA and CFA). Internal consistency and construct validity were also assessed by evaluating the association between the FIRST-S with symptoms of depression, anxiety, and sleep quality. Item response theory (IRT) analyses were conducted to complement classical test theory (CTT) analytic approaches. The mean score of the FIRST-S was 13.8 (range: 9-33). The results of the EFA showed that the FIRST-S contained a one-factor solution that accounted for 69.8% of the variance. The FIRST-S items showed good internal consistency (Cronbach α = 0.81). CFA results corroborated the one-factor structure finding from the EFA; and yielded measures indicating goodness of fit (comparative fit index of 0.902) and accuracy (root mean square error of approximation of 0.057). The FIRST-S had good construct validity as demonstrated by statistically significant associations of FIRST-S scores with sleep quality, antepartum depression and anxiety symptoms. Finally, results from IRT analyses suggested excellent item infit and outfit measures. The FIRST-S was found to have good construct validity and internal consistency for assessing vulnerability to insomnia during early pregnancy. © 2016 American Academy of Sleep Medicine.

Systems Biology Analysis of Zymomonas mobilis ZM4 Ethanol Stress Responses

PubMed Central

Yang, Shihui; Pan, Chongle; Tschaplinski, Timothy J.; Hurst, Gregory B.; Engle, Nancy L.; Zhou, Wen; Dam, PhuongAn; Xu, Ying; Rodriguez, Miguel; Dice, Lezlee; Johnson, Courtney M.; Davison, Brian H.; Brown, Steven D.

2013-01-01

Background Zymomonas mobilis ZM4 is a capable ethanologenic bacterium with high ethanol productivity and ethanol tolerance. Previous studies indicated that several stress-related proteins and changes in the ZM4 membrane lipid composition may contribute to ethanol tolerance. However, the molecular mechanisms of its ethanol stress response have not been elucidated fully. Methodology/Principal Findings In this study, ethanol stress responses were investigated using systems biology approaches. Medium supplementation with an initial 47 g/L (6% v/v) ethanol reduced Z. mobilis ZM4 glucose consumption, growth rate and ethanol productivity compared to that of untreated controls. A proteomic analysis of early exponential growth identified about one thousand proteins, or approximately 55% of the predicted ZM4 proteome. Proteins related to metabolism and stress response such as chaperones and key regulators were more abundant in the early ethanol stress condition. Transcriptomic studies indicated that the response of ZM4 to ethanol is dynamic, complex and involves many genes from all the different functional categories. Most down-regulated genes were related to translation and ribosome biogenesis, while the ethanol-upregulated genes were mostly related to cellular processes and metabolism. Transcriptomic data were used to update Z. mobilis ZM4 operon models. Furthermore, correlations among the transcriptomic, proteomic and metabolic data were examined. Among significantly expressed genes or proteins, we observe higher correlation coefficients when fold-change values are higher. Conclusions Our study has provided insights into the responses of Z. mobilis to ethanol stress through an integrated “omics” approach for the first time. This systems biology study elucidated key Z. mobilis ZM4 metabolites, genes and proteins that form the foundation of its distinctive physiology and its multifaceted response to ethanol stress. PMID:23874800

Early Life Stress, Mood, and Anxiety Disorders.

PubMed

Syed, Shariful A; Nemeroff, Charles B

2017-02-01

Early life stress has been shown to exert profound short- and long-term effects on human physiology both in the central nervous system and peripherally. Early life stress has demonstrated clear association with many psychiatric disorders including major depression, posttraumatic stress disorder, and bipolar disorder. The Diagnostic and Statistics Manuel of Mental Disorders (DSM) diagnostic categorical system has served as a necessary framework for clinical service, delivery, and research, however has not been completely matching the neurobiological research perspective. Early life stress presents a complex dynamic featuring a wide spectrum of physiologic alterations: from epigenetic alterations, inflammatory changes, to dysregulation of the hypothalamic pituitary axis and has further added to the challenge of identifying biomarkers associated with psychiatric disorders. The National Institute of Mental Health's proposed Research Domain Criteria initiative incorporates a dimensional approach to assess discrete domains and constructs of behavioral function that are subserved by identifiable neural circuits. The current neurobiology of early life stress is reviewed in accordance with dimensional organization of Research Domain Criteria matrix and how the findings as a whole fit within the Research Domain Criteria frameworks.

Metabolic Response to Heat Stress in Late-Pregnant and Early Lactation Dairy Cows: Implications to Liver-Muscle Crosstalk.

PubMed

Koch, Franziska; Lamp, Ole; Eslamizad, Mehdi; Weitzel, Joachim; Kuhla, Björn

2016-01-01

Climate changes lead to rising temperatures during summer periods and dramatic economic losses in dairy production. Modern high-yielding dairy cows experience severe metabolic stress during the transition period between late gestation and early lactation to meet the high energy and nutrient requirements of the fetus or the mammary gland, and additional thermal stress during this time has adverse implications on metabolism and welfare. The mechanisms enabling metabolic adaptation to heat apart from the decline in feed intake and milk yield are not fully elucidated yet. To distinguish between feed intake and heat stress related effects, German Holstein dairy cows were first kept at thermoneutral conditions at 15°C followed by exposure to heat-stressed (HS) at 28°C or pair-feeding (PF) at 15°C for 6 days; in late-pregnancy and again in early lactation. Liver and muscle biopsies and plasma samples were taken to assess major metabolic pathway regulation using real-time PCR and Western Blot. The results indicate that during heat stress, late pregnant cows activate Cahill but reduce Cori cycling, prevent increase in skeletal muscle fatty acid oxidation, and utilize increased amounts of pyruvate for gluconeogenesis, without altering ureagenesis despite reduced plane of nutrition. These homeorhetic adaptations are employed to reduce endogenous heat production while diverting amino acids to the growing fetus. Metabolic adaptation to heat stress in early lactation involves increased long-chain fatty acid degradation in muscle peroxisomes, allowance for muscle glucose utilization but diminished hepatic use of amino acid-derived pyruvate for gluconeogenesis and reduced peroxisomal fatty acid oxidation and ATP production in liver of HS compared to PF cows in early lactation. Consequently, metabolic adaptation to heat stress and reduced feed intake differ between late pregnancy and early lactation of dairy cows to maintain energy supply for fetus development or milk production

Metabolic Response to Heat Stress in Late-Pregnant and Early Lactation Dairy Cows: Implications to Liver-Muscle Crosstalk

PubMed Central

Eslamizad, Mehdi; Weitzel, Joachim; Kuhla, Björn

2016-01-01

Climate changes lead to rising temperatures during summer periods and dramatic economic losses in dairy production. Modern high-yielding dairy cows experience severe metabolic stress during the transition period between late gestation and early lactation to meet the high energy and nutrient requirements of the fetus or the mammary gland, and additional thermal stress during this time has adverse implications on metabolism and welfare. The mechanisms enabling metabolic adaptation to heat apart from the decline in feed intake and milk yield are not fully elucidated yet. To distinguish between feed intake and heat stress related effects, German Holstein dairy cows were first kept at thermoneutral conditions at 15°C followed by exposure to heat-stressed (HS) at 28°C or pair-feeding (PF) at 15°C for 6 days; in late-pregnancy and again in early lactation. Liver and muscle biopsies and plasma samples were taken to assess major metabolic pathway regulation using real-time PCR and Western Blot. The results indicate that during heat stress, late pregnant cows activate Cahill but reduce Cori cycling, prevent increase in skeletal muscle fatty acid oxidation, and utilize increased amounts of pyruvate for gluconeogenesis, without altering ureagenesis despite reduced plane of nutrition. These homeorhetic adaptations are employed to reduce endogenous heat production while diverting amino acids to the growing fetus. Metabolic adaptation to heat stress in early lactation involves increased long-chain fatty acid degradation in muscle peroxisomes, allowance for muscle glucose utilization but diminished hepatic use of amino acid-derived pyruvate for gluconeogenesis and reduced peroxisomal fatty acid oxidation and ATP production in liver of HS compared to PF cows in early lactation. Consequently, metabolic adaptation to heat stress and reduced feed intake differ between late pregnancy and early lactation of dairy cows to maintain energy supply for fetus development or milk production

Early sensory over-responsivity in toddlers with autism spectrum disorders as a predictor of family impairment and parenting stress.

PubMed

Ben-Sasson, A; Soto, T W; Martínez-Pedraza, F; Carter, A S

2013-08-01

Sensory over-responsivity (SOR) affects many individuals with autism spectrum disorders (ASD), often leading to stressful encounters during daily routines. This study describes the associations between early SOR symptoms and the longitudinal course of restrictions in family life activities and parenting stress across three time-points in families raising a child with ASD (n = 174). Covariates were child diagnostic severity, emotional problems, and maternal affective symptoms. At time 1 mean chronological age was 28.5 months. Children were administered the Autism Diagnostic Observation Schedule (ADOS) and Mullen Scales of Early Learning (MSEL). Parents completed the Infant Toddler Sensory Profile (ITSP), Infant-Toddler Social Emotional Assessment (ITSEA), Beck Anxiety Index (BAI), and the Center for Epidemiologic Studies Depression Inventory (CES-D) at time 1; and the Parenting Stress Index (PSI) and Family Life Impairment Scale (FLIS) at the three annual time-points. Latent Growth Curve Models indicated that higher SOR scores on the ITSP at time 1 were associated with higher initial levels of family life impairment and parenting stress and with a smaller magnitude of change over time. These associations were independent of severity of ADOS social-communication symptoms, MSEL composite score, ITSEA externalizing and anxiety symptoms, and maternal affective symptoms as measured by the BAI and CES-D. On average FLIS and PSI did not change over time, however, there was significant individual variability. Concurrently, SOR at time 1 explained 39-45% of the variance in family stress and impairment variables. An evaluation of SOR should be integrated into the assessment of toddlers with ASD considering their role in family life impairment and stress. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

Children's cortisol responses to a social evaluative laboratory stressor from early to middle childhood.

PubMed

Leppert, Katherine A; Kushner, Marissa; Smith, Victoria C; Lemay, Edward P; Dougherty, Lea R

2016-12-01

This study examined the stability of children's cortisol responses to a social evaluative laboratory stressor from early to middle childhood. Ninety-six children (51 males) completed stress-inducing laboratory tasks and provided five salivary cortisol samples in early (W1) and middle (W2) childhood. Although W1 cortisol responses did not predict W2 cortisol responses, children's cortisol responses demonstrated change: compared to their W1 cortisol responses, children's W2 cortisol responses demonstrated an increased slope and more negative quadratic curvature. Furthermore, child psychiatric symptoms at W1 moderated the stability of children's cortisol responses. Children with fewer preschool psychiatric symptoms demonstrated greater inter-individual and intra-individual stability, whereas children with higher preschool psychiatric symptoms and comorbidity demonstrated systematic inter-individual and intra-individual instability in cortisol responses over time. Findings suggest a developmental shift toward increasing cortisol stress responses from early to middle childhood and highlight preschool psychopathology as a moderator of stability in children's cortisol responses over time. © 2016 Wiley Periodicals, Inc.

Early Childhood Stress and Child Age Predict Longitudinal Increases in Obesogenic Eating Among Low-Income Children.

PubMed

Miller, Alison L; Gearhardt, Ashley N; Retzloff, Lauren; Sturza, Julie; Kaciroti, Niko; Lumeng, Julie C

2018-01-31

To identify whether psychosocial stress exposure during early childhood predicts subsequent increased eating in the absence of hunger (EAH), emotional overeating, food responsiveness, and enjoyment of food. This was an observational longitudinal study. Among 207 low-income children (54.6% non-Hispanic white, 46.9% girls), early childhood stress exposure was measured by parent report and a stress exposure index calculated, with higher scores indicating more stress exposure. Eating behaviors were measured in early (mean, 4.3; standard deviation, 0.5 years) and middle (mean, 7.9; standard deviation, 0.7 years) childhood. Observed EAH was assessed by measuring kilocalories of palatable food the child consumed after a meal. Parents reported on child eating behaviors on the Child Eating Behavior Questionnaire. Child weight and height were measured and body mass index z score (BMIz) calculated. Multivariable linear regression, adjusting for child sex, race/ethnicity, and BMIz, was used to examine the association of stress exposure with rate of change per year in each child eating behavior. Early childhood stress exposure predicted yearly increases in EAH (β = 0.14; 95% confidence interval, 0.002, 0.27) and Emotional Overeating (β = 0.14; 95% confidence interval, 0.008, 0.27). Stress exposure was not associated with Food Responsiveness (trend for decreased Enjoyment of Food; β = -0.13; 95% confidence interval, 0.002, -0.26). All child obesogenic eating behaviors increased with age (P < .05). Early stress exposure predicted increases in child eating behaviors known to associate with overweight/obesity. Psychosocial stress may confer overweight/obesity risk through eating behavior pathways. Targeting eating behaviors may be an important prevention strategy for children exposed to stress. Copyright © 2018 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

The influence of social environment in early life on the behavior, stress response, and reproductive system of adult male Norway rats selected for different attitudes to humans.

PubMed

Gulevich, R G; Shikhevich, S G; Konoshenko, M Yu; Kozhemyakina, R V; Herbeck, Yu E; Prasolova, L A; Oskina, I N; Plyusnina, I Z

2015-05-15

The influence of social disturbance in early life on behavior, response of blood corticosterone level to restraint stress, and endocrine and morphometric indices of the testes was studied in 2-month Norway rat males from three populations: not selected for behavior (unselected), selected for against aggression to humans (tame), and selected for increased aggression to humans (aggressive). The experimental social disturbance included early weaning, daily replacement of cagemates from days 19 to 25, and subsequent housing in twos till the age of 2months. The social disturbance increased the latent period of aggressive behavior in the social interaction test in unselected males and reduced relative testis weights in comparison to the corresponding control groups. In addition, experimental unselected rats had smaller diameters of seminiferous tubules and lower blood testosterone levels. In the experimental group, tame rats had lower basal corticosterone levels, and aggressive animals had lower hormone levels after restraint stress in comparison to the control. The results suggest that the selection in two directions for attitude to humans modifies the response of male rats to social disturbance in early life. In this regard, the selected rat populations may be viewed as a model for investigation of (1) neuroendocrinal mechanisms responsible for the manifestation of aggression and (2) interaction of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal systems in stress. Copyright © 2015 Elsevier Inc. All rights reserved.

Early life stress confers lifelong stress susceptibility in mice via ventral tegmental area OTX2.

PubMed

Peña, Catherine J; Kronman, Hope G; Walker, Deena M; Cates, Hannah M; Bagot, Rosemary C; Purushothaman, Immanuel; Issler, Orna; Loh, Yong-Hwee Eddie; Leong, Tin; Kiraly, Drew D; Goodman, Emma; Neve, Rachael L; Shen, Li; Nestler, Eric J

2017-06-16

Early life stress increases risk for depression. Here we establish a "two-hit" stress model in mice wherein stress at a specific postnatal period increases susceptibility to adult social defeat stress and causes long-lasting transcriptional alterations that prime the ventral tegmental area (VTA)-a brain reward region-to be in a depression-like state. We identify a role for the developmental transcription factor orthodenticle homeobox 2 ( Otx2 ) as an upstream mediator of these enduring effects. Transient juvenile-but not adult-knockdown of Otx2 in VTA mimics early life stress by increasing stress susceptibility, whereas its overexpression reverses the effects of early life stress. This work establishes a mechanism by which early life stress encodes lifelong susceptibility to stress via long-lasting transcriptional programming in VTA mediated by Otx2 . Copyright © 2017, American Association for the Advancement of Science.

Long-term programing of psychopathology-like behaviors in male rats by peripubertal stress depends on individual's glucocorticoid responsiveness to stress.

PubMed

Walker, Sophie E; Sandi, Carmen

2018-02-07

Experience of adversity early in life and dysregulation of hypothalamus-pituitary-adrenocortical (HPA) axis activity are risk factors often independently associated with the development of psychopathological disorders, including depression, PTSD and pathological aggression. Additional evidence suggests that in combination these factors may interact to shape the development and expression of psychopathology differentially, though little is known about underlying mechanisms. Here, we studied the long-term consequences of early life stress exposure on individuals with differential constitutive glucocorticoid responsiveness to repeated stressor exposure, assessing both socio-affective behaviors and brain activity in regions sensitive to pathological alterations following stress. Two rat lines, genetically selected for either low or high glucocorticoid responsiveness to repeated stress were exposed to a series of unpredictable, fear-inducing stressors on intermittent days during the peripuberty period. Results obtained at adulthood indicated that having high glucocorticoid responses to repeated stress and having experience of peripuberty stress independently enhanced levels of psychopathology-like behaviors, as well as increasing basal activity in several prefrontal and limbic brain regions in a manner associated with enhanced behavioral inhibition. Interestingly, peripuberty stress had a differential impact on aggression in the two rat lines, enhancing aggression in the low-responsive line but not in the already high-aggressive, high-responsive rats. Taken together, these findings indicate that aberrant HPA axis activity around puberty, a key period in the development of social repertoire in both rats and humans, may alter behavior such that it becomes anti-social in nature.

Early Life Stress: Effects on the Regulation of Anxiety Expression in Children and Adolescents.

PubMed

Burkholder, Amanda R; Koss, Kalsea J; Hostinar, Camelia E; Johnson, Anna E; Gunnar, Megan R

2016-11-01

This study examined children's ( N = 79; 9-10 years) and adolescents' ( N = 82; 15-16 years) ability to regulate their emotion expressions of anxiety as they completed a modified version of the Trier Social Stress Test for Children (TSST-C). Approximately half in each age group were internationally adopted from institutional care ( N = 79) and half were non-adopted, age-matched peers ( N = 82). Institutional care was viewed as a form of early life stress. Coders who were reliable and blind to group status watched videos of the session to assess anxiety expressions using the Child and Adolescent Stress and Emotion Scale developed for this study. Children exhibited more expressions of anxiety than adolescents, and youth adopted from institutions showed more expressions of anxiety than their non-adopted counterparts. The role of early life stress on observed anxiety expressions remained significant after controlling for differences in age, physiological stress responses measured through salivary cortisol reactivity, and self-reports of stress during the TSST-C. This suggests possible deficits in the regulation of expressive behavior for youth with early life stress histories, which cannot be explained by experiencing the task as more stressful.

Early Life Stress: Effects on the Regulation of Anxiety Expression in Children and Adolescents

PubMed Central

Burkholder, Amanda R; Koss, Kalsea J.; Hostinar, Camelia E; Johnson, Anna E.; Gunnar, Megan R

2017-01-01

This study examined children’s (N = 79; 9–10 years) and adolescents’ (N = 82; 15–16 years) ability to regulate their emotion expressions of anxiety as they completed a modified version of the Trier Social Stress Test for Children (TSST-C). Approximately half in each age group were internationally adopted from institutional care (N = 79) and half were non-adopted, age-matched peers (N = 82). Institutional care was viewed as a form of early life stress. Coders who were reliable and blind to group status watched videos of the session to assess anxiety expressions using the Child and Adolescent Stress and Emotion Scale developed for this study. Children exhibited more expressions of anxiety than adolescents, and youth adopted from institutions showed more expressions of anxiety than their non-adopted counterparts. The role of early life stress on observed anxiety expressions remained significant after controlling for differences in age, physiological stress responses measured through salivary cortisol reactivity, and self-reports of stress during the TSST-C. This suggests possible deficits in the regulation of expressive behavior for youth with early life stress histories, which cannot be explained by experiencing the task as more stressful. PMID:28584408

Maternal sensitivity and infant autonomic and endocrine stress responses.

PubMed

Bosquet Enlow, Michelle; King, Lucy; Schreier, Hannah Mc; Howard, Jamie M; Rosenfield, David; Ritz, Thomas; Wright, Rosalind J

2014-07-01

Early environmental exposures may help shape the development of the autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis, influencing vulnerability for health problems across the lifespan. Little is known about the role of maternal sensitivity in influencing the development of the ANS in early life. To examine associations among maternal sensitivity and infant behavioral distress and ANS and HPA axis reactivity to the Repeated Still-Face Paradigm (SFP-R), a dyadic stress task. Observational repeated measures study. Thirty-five urban, sociodemographically diverse mothers and their 6-month-old infants. Changes in infant affective distress, heart rate, respiratory sinus arrhythmia (RSA), and T-wave amplitude (TWA) across episodes of the SFP-R were assessed. A measure of cortisol output (area under the curve) in the hour following cessation of the SFP-R was also obtained. Greater maternal insensitivity was associated with greater infant sympathetic activation (TWA) during periods of stress and tended to be associated with greater cortisol output following the SFP-R. There was also evidence for greater affective distress and less parasympathetic activation (RSA) during the SFP-R among infants of predominantly insensitive mothers. Caregiving quality in early life may influence the responsiveness of the sympathetic and parasympathetic branches of the ANS as well as the HPA axis. Consideration of the ANS and HPA axis systems together provides a fuller representation of adaptive versus maladaptive stress responses. The findings highlight the importance of supporting high quality caregiving in the early years of life, which is likely to promote later health. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exercise-Induced Oxidative Stress Responses in the Pediatric Population

PubMed Central

Avloniti, Alexandra; Chatzinikolaou, Athanasios; Deli, Chariklia K.; Vlachopoulos, Dimitris; Gracia-Marco, Luis; Leontsini, Diamanda; Draganidis, Dimitrios; Jamurtas, Athanasios Z.; Mastorakos, George; Fatouros, Ioannis G.

2017-01-01

Adults demonstrate an upregulation of their pro- and anti-oxidant mechanisms in response to acute exercise while systematic exercise training enhances their antioxidant capacity, thereby leading to a reduced generation of free radicals both at rest and in response to exercise stress. However, less information exists regarding oxidative stress responses and the underlying mechanisms in the pediatric population. Evidence suggests that exercise-induced redox perturbations may be valuable in order to monitor exercise-induced inflammatory responses and as such training overload in children and adolescents as well as monitor optimal growth and development. The purpose of this review was to provide an update on oxidative stress responses to acute and chronic exercise in youth. It has been documented that acute exercise induces age-specific transient alterations in both oxidant and antioxidant markers in children and adolescents. However, these responses seem to be affected by factors such as training phase, training load, fitness level, mode of exercise etc. In relation to chronic adaptation, the role of training on oxidative stress adaptation has not been adequately investigated. The two studies performed so far indicate that children and adolescents exhibit positive adaptations of their antioxidant system, as adults do. More studies are needed in order to shed light on oxidative stress and antioxidant responses, following acute exercise and training adaptations in youth. Available evidence suggests that small amounts of oxidative stress may be necessary for growth whereas the transition to adolescence from childhood may promote maturation of pro- and anti-oxidant mechanisms. Available evidence also suggests that obesity may negatively affect basal and exercise-related antioxidant responses in the peripubertal period during pre- and early-puberty. PMID:28106721

Phosphatidylinositol 3-kinase function at very early symbiont perception: a local nodulation control under stress conditions?

PubMed

Robert, Germán; Muñoz, Nacira; Alvarado-Affantranger, Xochitl; Saavedra, Laura; Davidenco, Vanina; Rodríguez-Kessler, Margarita; Estrada-Navarrete, Georgina; Sánchez, Federico; Lascano, Ramiro

2018-04-09

Root hair curling is an early and essential morphological change required for the success of the symbiotic interaction between legumes and rhizobia. At this stage rhizobia grow as an infection thread within root hairs and are internalized into the plant cells by endocytosis, where the PI3K enzyme plays important roles. Previous observations show that stress conditions affect early stages of the symbiotic interaction, from 2 to 30 min post-inoculation, which we term as very early host responses, and affect symbiosis establishment. Herein, we demonstrated the relevance of the very early host responses for the symbiotic interaction. PI3K and the NADPH oxidase complex are found to have key roles in the microsymbiont recognition response, modulating the apoplastic and intracellular/endosomal ROS induction in root hairs. Interestingly, compared with soybean mutant plants that do not perceive the symbiont, we demonstrated that the very early symbiont perception under sublethal saline stress conditions induced root hair death. Together, these results highlight not only the importance of the very early host-responses on later stages of the symbiont interaction, but also suggest that they act as a mechanism for local control of nodulation capacity, prior to the abortion of the infection thread, preventing the allocation of resources/energy for nodule formation under unfavorable environmental conditions.

Effect of acute psychological stress on response inhibition: An event-related potential study.

PubMed

Qi, Mingming; Gao, Heming; Liu, Guangyuan

2017-04-14

This study aimed to investigate the effect of acute psychological stress on response inhibition and its electrophysiological correlates using a dual-task paradigm. Acute stress was induced by a primary task (mental arithmetic task), which consisted of a stress block and a control block. Response inhibition was measured using a secondary task (Go/NoGo task). In each trial, a Go/NoGo stimulus was presented immediately after the mental arithmetic task. The results revealed increased subjective stress and negative affect for the stress relative to control block, suggesting that the mental arithmetic task triggered a reliable stress response. ERPs locked to the Go/NoGo stimuli revealed that decreased P2 and increased N2 components were evoked for the stress block compared to the control block. These results demonstrated that acute psychological stress alters the response inhibition process by reducing the early selective attention process and enhancing the cognitive control process. Copyright © 2017 Elsevier B.V. All rights reserved.

Predictors of Treatment Response to Fluoxetine in PTSD Following a Recent History of War Zone Stress Exposure

DTIC Science & Technology

2010-07-01

routinely prescribed for acute stress disorder and early PTSD and recommended in the VA-DoD best practice guidelines, the efficacy of SSRIs as an early...selective serotonin reuptake inhibitors (SSRIs) are routinely prescribed for acute stress disorder and early PTSD and recommended in the VA-DoD best practice...1-0283 TITLE: Predictors of Treatment Response to Fluoxetine in PTSD Following a Recent History of War Zone Stress Exposure

Late-Onset Cognitive Impairments after Early-Life Stress Are Shaped by Inherited Differences in Stress Reactivity

PubMed Central

McIlwrick, Silja; Pohl, Tobias; Chen, Alon; Touma, Chadi

2017-01-01

Early-life stress (ELS) has been associated with lasting cognitive impairments and with an increased risk for affective disorders. A dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis, the body’s main stress response system, is critically involved in mediating these long-term consequences of adverse early-life experience. It remains unclear to what extent an inherited predisposition for HPA axis sensitivity or resilience influences the relationship between ELS and cognitive impairments, and which neuroendocrine and molecular mechanisms may be involved. To investigate this, we exposed animals of the stress reactivity mouse model, consisting of three independent lines selectively bred for high (HR), intermediate (IR), or low (LR) HPA axis reactivity to a stressor, to ELS and assessed their cognitive performance, neuroendocrine function and hippocampal gene expression in early and in late adulthood. Our results show that HR animals that were exposed to ELS exhibited an HPA axis hyper-reactivity in early and late adulthood, associated with cognitive impairments in hippocampus-dependent tasks, as well as molecular changes in transcript levels involved in the regulation of HPA axis activity (Crh) and in neurotrophic action (Bdnf). In contrast, LR animals showed intact cognitive function across adulthood, with no change in stress reactivity. Intriguingly, LR animals that were exposed to ELS even showed significant signs of enhanced cognitive performance in late adulthood, which may be related to late-onset changes observed in the expression of Crh and Crhr1 in the dorsal hippocampus of these animals. Collectively, our findings demonstrate that the lasting consequences of ELS at the level of cognition differ as a function of inherited predispositions and suggest that an innate tendency for low stress reactivity may be protective against late-onset cognitive impairments after ELS. PMID:28261058

Effect of childhood physical abuse on cortisol stress response.

PubMed

Carpenter, Linda L; Shattuck, Thaddeus T; Tyrka, Audrey R; Geracioti, Thomas D; Price, Lawrence H

2011-03-01

Abuse and neglect are highly prevalent in children and have enduring neurobiological effects. Stressful early life environments perturb the hypothalamic-pituitary-adrenal (HPA) axis, which in turn may predispose to psychiatric disorders in adulthood. However, studies of childhood maltreatment and adult HPA function have not yet rigorously investigated the differential effects of maltreatment subtypes, including physical abuse. In this study, we sought to replicate our previous finding that childhood maltreatment was associated with attenuated cortisol responses to stress and determine whether the type of maltreatment was a determinant of the stress response. Salivary cortisol response to the Trier Social Stress Test (TSST) was examined in a non-clinical sample of women (n = 110). Subjects had no acute medical problems and were not seeking psychiatric treatment. Effects of five maltreatment types, as measured by the Childhood Trauma Questionnaire, on cortisol response to the TSST were investigated. To further examine the significant (p < 0.005) effect of one maltreatment type, women with childhood physical abuse (PA) (n = 20) were compared to those without past PA (n = 90). Women reporting childhood PA displayed a significantly blunted cortisol response to the TSST compared with subjects without PA, after controlling for estrogen use, age, other forms of maltreatment, and other potential confounds. There were no differences between PA and control groups with regard to physiological arousal during the stress challenge. In a non-clinical sample of women with minimal or no current psychopathology, physical abuse is associated with a blunted cortisol response to a psychosocial stress task.

Analysis of plant hormone profiles in response to moderate dehydration stress.

PubMed

Urano, Kaoru; Maruyama, Kyonoshin; Jikumaru, Yusuke; Kamiya, Yuji; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

2017-04-01

Plant responses to dehydration stress are mediated by highly complex molecular systems involving hormone signaling and metabolism, particularly the major stress hormone abscisic acid (ABA) and ABA-dependent gene expression. To understand the roles of plant hormones and their interactions during dehydration, we analyzed the plant hormone profiles with respect to dehydration responses in Arabidopsis thaliana wild-type (WT) plants and ABA biosynthesis mutants (nced3-2). We developed a procedure for moderate dehydration stress, and then investigated temporal changes in the profiles of ABA, jasmonic acid isoleucine (JA-Ile), salicylic acid (SA), cytokinin (trans-zeatin, tZ), auxin (indole-acetic acid, IAA), and gibberellin (GA 4 ), along with temporal changes in the expression of key genes involved in hormone biosynthesis. ABA levels increased in a bi-phasic pattern (at the early and late phases) in response to moderate dehydration stress. JA-Ile levels increased slightly in WT plants and strongly increased in nced3-2 mutant plants at 72 h after the onset of dehydration. The expression profiles of dehydration-inducible genes displayed temporal responses in an ABA-dependent manner. The early phase of ABA accumulation correlated with the expression of touch-inducible genes and was independent of factors involved in the major ABA regulatory pathway, including the ABA-responsive element-binding (AREB/ABF) transcription factor. JA-Ile, SA, and tZ were negatively regulated during the late dehydration response phase. Transcriptome analysis revealed important roles for hormone-related genes in metabolism and signaling during dehydration-induced plant responses. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Early-Life Social Isolation Stress Increases Kappa Opioid Receptor Responsiveness and Downregulates the Dopamine System

PubMed Central

Karkhanis, Anushree N; Rose, Jamie H; Weiner, Jeffrey L; Jones, Sara R

2016-01-01

Chronic early-life stress increases vulnerability to alcoholism and anxiety disorders during adulthood. Similarly, rats reared in social isolation (SI) during adolescence exhibit augmented ethanol intake and anxiety-like behaviors compared with group housed (GH) rats. Prior studies suggest that disruption of dopamine (DA) signaling contributes to SI-associated behaviors, although the mechanisms underlying these alterations are not fully understood. Kappa opioid receptors (KORs) have an important role in regulating mesolimbic DA signaling, and other kinds of stressors have been shown to augment KOR function. Therefore, we tested the hypothesis that SI-induced increases in KOR function contribute to the dysregulation of NAc DA and the escalation in ethanol intake associated with SI. Our ex vivo voltammetry experiments showed that the inhibitory effects of the kappa agonist U50,488 on DA release were significantly enhanced in the NAc core and shell of SI rats. Dynorphin levels in NAc tissue were observed to be lower in SI rats. Microdialysis in freely moving rats revealed that SI was also associated with reduced baseline DA levels, and pretreatment with the KOR antagonist nor-binaltorphimine (nor-BNI) increased DA levels selectively in SI subjects. Acute ethanol elevated DA in SI and GH rats and nor-BNI pretreatment augmented this effect in SI subjects, while having no effect on ethanol-stimulated DA release in GH rats. Together, these data suggest that KORs may have increased responsiveness following SI, which could lead to hypodopaminergia and contribute to an increased drive to consume ethanol. Indeed, SI rats exhibited greater ethanol intake and preference and KOR blockade selectively attenuated ethanol intake in SI rats. Collectively, the findings that nor-BNI reversed SI-mediated hypodopaminergic state and escalated ethanol intake suggest that KOR antagonists may represent a promising therapeutic strategy for the treatment of alcohol use disorders, particularly

Stress resilience in early marriage: can practice make perfect?

PubMed

Neff, Lisa A; Broady, Elizabeth F

2011-11-01

As all couples experience stressful life events, addressing how couples adapt to stress is imperative for understanding marital development. Drawing from theories of stress inoculation, which suggest that the successful adaptation to moderately stressful events may help individuals develop a resilience to future stress, the current studies examined whether experiences with manageable stressors early in the marriage may serve to make the relationship more resilient to future stress. In Study 1, 61 newlywed couples provided data regarding their stressful life events, relationship resources (i.e., observed problem-solving behaviors), and marital satisfaction at multiple points over 2½ years. Results revealed that among spouses displaying more effective problem-solving behaviors, those who experienced moderate stress during the early months of marriage exhibited fewer future stress spillover effects and reported greater increases in felt efficacy than did spouses who had less experience with early stress. Study 2 examined stress resilience following the transition to parenthood in a new sample of 50 newlywed couples. Again, spouses who experienced moderate stress during the early months of marriage and had good initial relationship resources (i.e., observed support behaviors) reported greater marital adjustment following the transition to parenthood than did spouses who had good initial resources but less prior experience coping with stress. Together, results indicate that entering marriage with better relationship resources may not be sufficient to shield marital satisfaction from the detrimental effects of stress; rather, couples may also need practice in using those resources to navigate manageable stressful events.

Reduced resistance to oxidative stress during reproduction as a cost of early-life stress.

PubMed

Zimmer, Cédric; Spencer, Karen A

2015-05-01

Stress exposure during early-life development can have long-term consequences for a variety of biological functions including oxidative stress. The link between early-life stress and oxidative balance is beginning to be explored and previous studies have focused on this link in adult non-breeding or immature individuals. However, as oxidative stress is considered as the main physiological mechanism underlying the trade-off between self-maintenance and investment in reproduction, it is necessary to look at the consequences of early-life stress on oxidative status during reproduction. Here, we investigated the effects of exposure to pre- and/or post-natal stress on oxidative balance during reproduction under benign or stressful environmental conditions in an avian model species, the Japanese quail. We determined total antioxidant status (TAS), total oxidant status (TOS) and resistance to a free-radical attack in individual exposed to pre-natal stress, post-natal stress or both and in control individuals exposed to none of the stressors. TAS levels decreased over time in all females that reproduced under stressful conditions. TOS decreased between the beginning and the end of reproductive period in pre-natal control females. In all females, resistance to a free-radical attack decreased over the reproductive event but this decrease was more pronounced in females from a pre-natal stress development. Our results suggest that pre-natal stress may be associated with a higher cost of reproduction in terms of oxidative stress. These results also confirm that early-life stress can be associated with both benefits and costs depending of the life-history stage or environmental context. Copyright © 2014 Elsevier Inc. All rights reserved.

Early life stress and trauma and enhanced limbic activation to emotionally valenced faces in depressed and healthy children.

PubMed

Suzuki, Hideo; Luby, Joan L; Botteron, Kelly N; Dietrich, Rachel; McAvoy, Mark P; Barch, Deanna M

2014-07-01

Previous studies have examined the relationships between structural brain characteristics and early life stress in adults. However, there is limited evidence for functional brain variation associated with early life stress in children. We hypothesized that early life stress and trauma would be associated with increased functional brain activation response to negative emotional faces in children with and without a history of depression. Psychiatric diagnosis and life events in children (starting at age 3-5 years) were assessed in a longitudinal study. A follow-up magnetic resonance imaging (MRI) study acquired data (N = 115 at ages 7-12, 51% girls) on functional brain response to fearful, sad, and happy faces relative to neutral faces. We used a region-of-interest mask within cortico-limbic areas and conducted regression analyses and repeated-measures analysis of covariance. Greater activation responses to fearful, sad, and happy faces in the amygdala and its neighboring regions were found in children with greater life stress. Moreover, an association between life stress and left hippocampal and globus pallidus activity depended on children's diagnostic status. Finally, all children with greater life trauma showed greater bilateral amygdala and cingulate activity specific to sad faces but not the other emotional faces, although right amygdala activity was moderated by psychiatric status. These findings suggest that limbic hyperactivity may be a biomarker of early life stress and trauma in children and may have implications in the risk trajectory for depression and other stress-related disorders. However, this pattern varied based on emotion type and history of psychopathology. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Early intervention for post-traumatic stress disorder.

PubMed

Bryant, Richard A

2007-02-01

The potentially debilitating effect of posttraumatic stress disorder (PTSD) has created much interest in early intervention strategies that can reduce PTSD. This review critiques the evidence for psychological debriefing approaches and alternate early intervention strategies. The review critiques the randomized controlled trials of psychological debriefing, and early provision of cognitive behavior therapy. The latter approach involves therapy attention on acutely traumatized individuals who are high risk for PTSD development, and particularly in people with acute stress disorder (ASD). Psychological debriefing does not prevent PTSD. Cognitive behaviour therapy strategies have proven efficacy in reducing subsequent PTSD in ASD populations. Despite the promising evidence for early provision of CBT, many people do not benefit from CBT. This review concludes with consideration of major challenges facing early intervention approaches in the context of terrorist attacks and mass disasters.

Differential stress responses among newly received calves: variations in reductant capacity and Hsp gene expression

PubMed Central

Eitam, Harel; Vaya, Jacob; Brosh, Arieh; Orlov, Ala; Khatib, Soliman; Izhaki, Ido

2010-01-01

Bovine respiratory disease complex (BRD), a major economic concern to the beef cattle industry all over the world, is triggered by physical, biological and psychological stresses. It is becoming noticeable that the key to reducing BRD appears to be centered at reducing the response to stress. The aims of the present study were to detect individual variations in the stress response of newly received young calves through their leukocyte heat shock protein (Hsp) response, selected neutrophil-related gene expression and oxidative stress, and relate them to pulmonary adhesions at slaughter, an indicative sign of clinical and subclinical episodes of BRD at an early age. Differential expression patterns of Hsp60 and Hsp70A1A were revealed in newly received calves 1 h, 5 h and 1 day after arrival, distinguishing between stress-responsive and non-stress-responsive individuals. Plasma cortisol was also indicative of stress-responsive and non-stress-responsive individuals, 1 h and 5 h after arrival. At the longer term, β-glycan levels were highest 7 days after arrival and significantly correlated with an adhesion-free phenotype at slaughter. Oxidative stress responses, measured through the oxidation products of the exogenous linoleoyl tyrosine (LT) marker, revealed that hydroperoxidation and epoxidation of membranes may readily occur. Based on the LT oxidation products and levels of β-glycan, we present a discriminant analysis model, according to which vulnerable individuals may be predicted at near 100% probability 7 days after arrival. Since clinical signs of BRD may often go undetected in feedlot calves, such a model, after its examination in large-scale experiments, may be a reliable tool for an early prediction of subclinical signs of BRD. PMID:20401744

Stress in Early Childhood: Helping Children and Their Carers

ERIC Educational Resources Information Center

Thomas, Patrice

2006-01-01

This book offers practical and effective strategies for stress management for both early childhood staff and the children in their care. Here, the author uncovers valuable insights into the causes of stress and outlines a range of activities to counteract it. Early childhood practitioners know that theirs is both a stressful and rewarding…

Identifying key features of early stressful experiences that produce stress vulnerability and resilience in primates

PubMed Central

Parker, Karen J.; Maestripieri, Dario

2010-01-01

This article examines the complex role of early stressful experiences in producing both vulnerability and resilience to later stress-related psychopathology in a variety of primate models of human development. Two types of models are reviewed: Parental Separation Models (e.g., isolate-rearing, peer-rearing, parental separations, and stress inoculation) and Maternal Behavior Models (e.g., foraging demands, variation in maternal style, and maternal abuse). Based on empirical evidence, it is argued that early life stress exposure does not increase adult vulnerability to stress-related psychopathology as a linear function, as is generally believed, but instead reflects a quadratic function. Features of early stress exposure including the type, duration, frequency, ecological validity, sensory modality, and developmental timing, within and between species, are identified to better understand how early stressful experiences alter neurobiological systems to produce such diverse developmental outcomes. This article concludes by identifying gaps in our current knowledge, providing directions for future research, and discussing the translational implications of these primate models for human development and psychopathology. PMID:20851145

The Surgically Induced Stress Response

PubMed Central

Finnerty, Celeste C.; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A.; Herndon, David N.

2013-01-01

The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes which induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress response, however, varies according to the severity of injury (surgical or traumatic). This spectrum of injuries and insults ranges from small lacerations to severe insults such as large poly-traumatic and burn injuries. Although the stress response to acute trauma evolved to improve chances of survival following injury, in modern surgical practice the stress response can be detrimental. PMID:24009246

Early life influences on emotional reactivity: evidence that social enrichment has greater effects than handling on anxiety-like behaviors, neuroendocrine responses to stress and central BDNF levels.

PubMed

Cirulli, Francesca; Berry, Alessandra; Bonsignore, Luca Tommaso; Capone, Francesca; D'Andrea, Ivana; Aloe, Luigi; Branchi, Igor; Alleva, Enrico

2010-05-01

During the early post-natal phases the brain is experience-seeking and provided by a considerable plasticity which allows a fine tuning between the external environment and the developing organism. Since the early work of Seymour Levine, an impressive amount of research has clearly shown that stressful experiences exert powerful effects on the brain and body development. These effects can last throughout the entire life span influencing brain function and increasing the risk for depression and anxiety disorders. The mechanisms underlying the effects of early stress on the developing organism have been widely studied in rodents through experimental manipulations of the post-natal environment, such as handling, which have been shown to exert important effects on the emotional phenotype and the response to stress. In the present paper we review the relevant literature and present some original data indicating that, compared to handling, which imposes an external manipulation on the mother-infant relationship, social enrichment, in the form of communal rearing, in mice has very profound effects on animal's emotionality and the response to stress. These effects are also accompanied by important changes in central levels of brain-derived neurotrophic factor. The present data indicate that communal rearing has more pervasive effects than handling, strengthening previous data suggesting that it is a good animal model of reduced susceptibility to depression-like behavior. Overall, the availability of ever more sophisticated animal models represents a fundamental tool to translate basic research data into appropriate interventions for humans raised under traumatic or impoverished situations. (c) 2010 Elsevier Ltd. All rights reserved.

Plant Nucleolar Stress Response, a New Face in the NAC-Dependent Cellular Stress Responses.

PubMed

Ohbayashi, Iwai; Sugiyama, Munetaka

2017-01-01

The nucleolus is the most prominent nuclear domain, where the core processes of ribosome biogenesis occur vigorously. All these processes are finely orchestrated by many nucleolar factors to build precisely ribosome particles. In animal cells, perturbations of ribosome biogenesis, mostly accompanied by structural disorders of the nucleolus, cause a kind of cellular stress to induce cell cycle arrest, senescence, or apoptosis, which is called nucleolar stress response. The best-characterized pathway of this stress response involves p53 and MDM2 as key players. p53 is a crucial transcription factor that functions in response to not only nucleolar stress but also other cellular stresses such as DNA damage stress. These cellular stresses release p53 from the inhibition by MDM2, an E3 ubiquitin ligase targeting p53, in various ways, which leads to p53-dependent activation of a set of genes. In plants, genetic impairments of ribosome biogenesis factors or ribosome components have been shown to cause characteristic phenotypes, including a narrow and pointed leaf shape, implying a common signaling pathway connecting ribosomal perturbations and certain aspects of growth and development. Unlike animals, however, plants have neither p53 nor MDM2 family proteins. Then the question arises whether plant cells have a nucleolar stress response pathway. In recent years, it has been reported that several members of the plant-specific transcription factor family NAC play critical roles in the pathways responsive to various cellular stresses. In this mini review, we outline the plant cellular stress response pathways involving NAC transcription factors with reference to the p53-MDM2-dependent pathways of animal cells, and discuss the possible involvement of a plant-unique, NAC-mediated pathway in the nucleolar stress response in plants.

Early-Life Stress Is Associated with Gender-Based Vulnerability to Epileptogenesis in Rat Pups

PubMed Central

Desgent, Sébastien; Duss, Sandra; Sanon, Nathalie T.; Lema, Pablo; Lévesque, Maxime; Hébert, David; Rébillard, Rose-Marie; Bibeau, Karine; Brochu, Michèle; Carmant, Lionel

2012-01-01

During development, the risk of developing mesial temporal lobe epilepsy (MTLE) increases when the developing brain is exposed to more than one insult in early life. Early life insults include abnormalities of cortical development, hypoxic-ischemic injury and prolonged febrile seizures. To study epileptogenesis, we have developed a two-hit model of MTLE characterized by two early-life insults: a freeze lesion-induced cortical malformation at post-natal day 1 (P1), and a prolonged hyperthermic seizure (HS) at P10. As early life stressors lead to sexual dimorphism in both acute response and long-term outcome, we hypothesized that our model could lead to gender-based differences in acute stress response and long-term risk of developing MTLE. Male and female pups underwent a freeze-lesion induced cortical microgyrus at P1 and were exposed to HS at P10. Animals were monitored by video-EEG from P90 to P120. Pre and post-procedure plasma corticosterone levels were used to measure stress response at P1 and P10. To confirm the role of sex steroids, androgenized female pups received daily testosterone injections to the mother pre-natally and post-natally for nine days while undergoing both insults. We demonstrated that after both insults females did not develop MTLE while all males did. This correlated with a rise in corticosterone levels at P1 following the lesion in males only. Interestingly, all androgenized females showed a similar rise in corticosterone at P1, and also developed MTLE. Moreover, we found that the cortical lesion significantly decreased the latency to generalized convulsion during hyperthermia at P10 in both genders. The cortical dysplasia volumes at adulthood were also similar between male and female individuals. Our data demonstrate sexual dimorphism in long-term vulnerability to develop epilepsy in the lesion + hyperthermia animal model of MTLE and suggest that the response to early-life stress at P1 contributes significantly to epileptogenesis in a

Analysis of Stress-Responsive Gene Expression in Cultivated and Weedy Rice Differing in Cold Stress Tolerance

PubMed Central

Pereira, Andy; Tseng, Te-Ming; Zimmer, Paulo Dejalma; Burgos, Nilda Roma

2015-01-01

Rice (Oryza sativa L.) cultivars show impairment of growth in response to environmental stresses such as cold at the early seedling stage. Locally adapted weedy rice is able to survive under adverse environmental conditions, and can emerge in fields from greater soil depth. Cold-tolerant weedy rice can be a good genetic source for developing cold-tolerant, weed-competitive rice cultivars. An in-depth analysis is presented here of diverse indica and japonica rice genotypes, mostly weedy rice, for cold stress response to provide an understanding of different stress adaptive mechanisms towards improvement of the rice crop performance in the field. We have tested a collection of weedy rice genotypes to: 1) classify the subspecies (ssp.) grouping (japonica or indica) of 21 accessions; 2) evaluate their sensitivity to cold stress; and 3) analyze the expression of stress-responsive genes under cold stress and a combination of cold and depth stress. Seeds were germinated at 25°C at 1.5- and 10-cm sowing depth for 10d. Seedlings were then exposed to cold stress at 10°C for 6, 24 and 96h, and the expression of cold-, anoxia-, and submergence-inducible genes was analyzed. Control plants were seeded at 1.5cm depth and kept at 25°C. The analysis revealed that cold stress signaling in indica genotypes is more complex than that of japonica as it operates via both the CBF-dependent and CBF-independent pathways, implicated through induction of transcription factors including OsNAC2, OsMYB46 and OsF-BOX28. When plants were exposed to cold + sowing depth stress, a complex signaling network was induced that involved cross talk between stresses mediated by CBF-dependent and CBF-independent pathways to circumvent the detrimental effects of stresses. The experiments revealed the importance of the CBF regulon for tolerance to both stresses in japonica and indica ssp. The mechanisms for cold tolerance differed among weedy indica genotypes and also between weedy indica and cultivated

The effects of brain serotonin deficiency on behavioural disinhibition and anxiety-like behaviour following mild early life stress.

PubMed

Sachs, Benjamin D; Rodriguiz, Ramona M; Siesser, William B; Kenan, Alexander; Royer, Elizabeth L; Jacobsen, Jacob P R; Wetsel, William C; Caron, Marc G

2013-10-01

Aberrant serotonin (5-HT) signalling and exposure to early life stress have both been suggested to play a role in anxiety- and impulsivity-related behaviours. However, whether congenital 5-HT deficiency × early life stress interactions influence the development of anxiety- or impulsivity-like behaviour has not been established. Here, we examined the effects of early life maternal separation (MS) stress on anxiety-like behaviour and behavioural disinhibition, a type of impulsivity-like behaviour, in wild-type (WT) and tryptophan hydroxylase 2 (Tph2) knock-in (Tph2KI) mice, which exhibit ~60-80% reductions in the levels of brain 5-HT due to a R439H mutation in Tph2. We also investigated the effects of 5-HT deficiency and early life stress on adult hippocampal neurogenesis, plasma corticosterone levels and several signal transduction pathways in the amygdala. We demonstrate that MS slightly increases anxiety-like behaviour in WT mice and induces behavioural disinhibition in Tph2KI animals. We also demonstrate that MS leads to a slight decrease in cell proliferation within the hippocampus and potentiates corticosterone responses to acute stress, but these effects are not affected by brain 5-HT deficiency. However, we show that 5-HT deficiency leads to significant alterations in SGK-1 and GSK3β signalling and NMDA receptor expression in the amygdala in response to MS. Together, these findings support a potential role for 5-HT-dependent signalling in the amygdala in regulating the long-term effects of early life stress on anxiety-like behaviour and behavioural disinhibition.

Initial water deficit effects on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance: metabolic reorganization prior to early stress responses.

PubMed

Pinheiro, Carla; António, Carla; Ortuño, Maria Fernanda; Dobrev, Petre I; Hartung, Wolfram; Thomas-Oates, Jane; Ricardo, Cândido Pinto; Vanková, Radomira; Chaves, M Manuela; Wilson, Julie C

2011-10-01

The early (2-4 d) effects of slowly imposed soil water deficit on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance in different organs (leaf blade, stem stele, stem cortex, and root) were evaluated on 23-d-old plants (growth chamber assay). Our work shows that several metabolic adjustments occurred prior to alteration of the plant water status, implying that water deficit is perceived before the change in plant water status. The slow, progressive decline in soil water content started to be visible 3 d after withholding water (3 DAW). The earliest plant changes were associated with organ-specific metabolic responses (particularly in the leaves) and with leaf conductance and only later with plant water status and photosynthetic rate (4 DAW) or photosynthetic capacity (according to the Farquhar model; 6 DAW). Principal component analysis (PCA) of the physiological parameters, the carbohydrate and the hormone levels and their relative values, as well as leaf water-soluble metabolites full scan data (LC-MS/MS), showed separation of the different sampling dates. At 6 DAW classically described stress responses are observed, with plant water status, ABA level, and root hormonal balance contributing to the separation of these samples. Discrimination of earlier stress stages (3 and 4 DAW) is only achieved when the relative levels of indole-3-acetic acid (IAA), cytokinins (Cks), and carbon metabolism (glucose, sucrose, raffinose, and starch levels) are taken into account. Our working hypothesis is that, in addition to single responses (e.g. ABA increase), the combined alterations in hormone and carbohydrate levels play an important role in the stress response mechanism. Response to more advanced stress appears to be associated with a combination of cumulative changes, occurring in several plant organs. The carbohydrate and hormonal balance in the leaf (IAA to bioactive-Cks; soluble sugars to IAA and starch to IAA; relative abundances of the

Bruxism affects stress responses in stressed rats.

PubMed

Sato, Chikatoshi; Sato, Sadao; Takashina, Hirofumi; Ishii, Hidenori; Onozuka, Minoru; Sasaguri, Kenichi

2010-04-01

It has been proposed that suppression of stress-related emotional responses leads to the simultaneous activation of both sympathetic and parasympathetic divisions of the autonomic nervous system (ANS) and that the expression of these emotional states has a protective effect against ulcerogenesis. In the present study, we investigated whether stress-induced bruxism activity (SBA) has a physiological effect of on the stress-induced changes of the stomach, thymus, and spleen as well as blood leukocytes, cortisol, and adrenaline. This study demonstrated that SBA attenuated the stress-induced ulcer genesis as well as degenerative changes of thymus and spleen. SBA also attenuated increases of adrenaline, cortisol, and neutrophils in the blood. In conclusion, expression of aggression through SBA during stress exposure attenuates both stress-induced ANS response, including gastric ulcer formation.

Ontogeny of the stress response in chinook salmon, Oncorhynchus tshawytscha

USGS Publications Warehouse

Feist, G.; Schreck, C.B.

2001-01-01

Whole body concentrations of cortisol were determined via radioimmunoassay in chinook salmon, Onchorynchus tshawytscha, during early development in both stressed and non-stressed fish to determine when the corticosteroidogenic stress response first appeared. Progeny from both pooled and individual females were examined to determine if differences existed in offspring from different females. Levels of cortisol were low in eyed eggs, increased at hatch, decreased 2 weeks later and then remained constant thereafter. Differences in cortisol between stressed and control fish were found 1 week after hatch and persisted for the remainder of the study. The magnitude of the stress response, or relative amount of cortisol produced, generally increased from the time when it was first detected, but a decrease in the ability to elicit cortisol was seen 4 weeks after hatching. Cortisol content of separate progeny from two individual females showed a similar pattern to that seen in pooled eggs. Our results indicate that chinook salmon are capable of producing cortisol following a stressful event approximately 1 week after the time of hatching. The decrease in endogenous cortisol content seen 2 weeks after hatching, and the decrease in the magnitude of the stress response seen 4 weeks after hatching may be comparable to developmental events documented in mammals where corticosteroid synthesis is inhibited to neutralize possible detrimental effects of these hormones during critical periods of development.

Perceived Stress and Canadian Early Childcare Educators

ERIC Educational Resources Information Center

Wagner, Shannon L.; Forer, Barry; Cepeda, Ivan L.; Goelman, Hillel; Maggi, Stefania; D'Angiulli, Amedeo; Wessel, Julie; Hertzman, Clyde; Grunau, Ruth E.

2013-01-01

Background: Occupational stress for early childcare educators is an area of apparent understudy in the literature. The present study attempted to address this gap and provide some updated data regarding the experiences of this occupational group. Methods: Early childhood workers across a variety of early childhood education settings (N = 69)…

Callous-unemotional traits and early life stress predict treatment effects on stress and sex hormone functioning in incarcerated male adolescents.

PubMed

Johnson, Megan; Vitacco, Michael J; Shirtcliff, Elizabeth A

2018-03-01

The stress response system is highly plastic, and hormone rhythms may "adaptively calibrate" in response to treatment. This investigation assessed whether stress and sex hormone diurnal rhythms changed over the course of behavioral treatment, and whether callous-unemotional (CU) traits and history of early adversity affected treatment results on diurnal hormone functioning in a sample of 28 incarcerated adolescent males. It was hypothesized that the treatment would have beneficial effects, such that healthier diurnal rhythms would emerge post-treatment. Diurnal cortisol, testosterone, and dehydroepiandrosterone (DHEA) were sampled two weeks after admission to the correctional/treatment facility, and again approximately four months later. Positive treatment effects were detected for the whole sample, such that testosterone dampened across treatment. CU traits predicted a non-optimal hormone response to treatment, potentially indicating biological preparedness to respond to acts of social dominance and aggression. The interaction between CU traits and adversity predicted a promising and sensitized response to treatment including increased cortisol and a steeper testosterone drop across treatment. Results suggest that stress and sex hormones are highly receptive to treatment during this window of development.

Genome-wide analysis identifies chickpea (Cicer arietinum) heat stress transcription factors (Hsfs) responsive to heat stress at the pod development stage.

PubMed

Chidambaranathan, Parameswaran; Jagannadham, Prasanth Tej Kumar; Satheesh, Viswanathan; Kohli, Deshika; Basavarajappa, Santosh Halasabala; Chellapilla, Bharadwaj; Kumar, Jitendra; Jain, Pradeep Kumar; Srinivasan, R

2018-05-01

The heat stress transcription factors (Hsfs) play a prominent role in thermotolerance and eliciting the heat stress response in plants. Identification and expression analysis of Hsfs gene family members in chickpea would provide valuable information on heat stress responsive Hsfs. A genome-wide analysis of Hsfs gene family resulted in the identification of 22 Hsf genes in chickpea in both desi and kabuli genome. Phylogenetic analysis distinctly separated 12 A, 9 B, and 1 C class Hsfs, respectively. An analysis of cis-regulatory elements in the upstream region of the genes identified many stress responsive elements such as heat stress elements (HSE), abscisic acid responsive element (ABRE) etc. In silico expression analysis showed nine and three Hsfs were also expressed in drought and salinity stresses, respectively. Q-PCR expression analysis of Hsfs under heat stress at pod development and at 15 days old seedling stage showed that CarHsfA2, A6, and B2 were significantly upregulated in both the stages of crop growth and other four Hsfs (CarHsfA2, A6a, A6c, B2a) showed early transcriptional upregulation for heat stress at seedling stage of chickpea. These subclasses of Hsfs identified in this study can be further evaluated as candidate genes in the characterization of heat stress response in chickpea.

Reactive oxygen species in response of plants to gravity stress

NASA Astrophysics Data System (ADS)

Jadko, Sergiy

2016-07-01

Reactive oxygen species (ROS) as second messengers can induce stress response of plants. Thioredoxins (Trx) and peroxiredoxins (Prx) can function as sensors and transmitters of the ROS in stress signaling and antioxidant response. 12-14 days old tissue culture of Arabidopsis thaliana have been investigated. Hypergravity stress was induced by centrifugation at 10 and 20 g during 30 and 90 min and than intensity of spontaneous chemiluminescence (SChL/ROS content), Trx and Prx activities were determined. All experiments were repeated from 3 to 5 times and the obtained data were statistically treated. In the tissue culture under development of the stress there were an increase in intensity of SChL and Trx and Prx activities. Thus, under hypergravity stress in the plant occurred early increase in the ROS level and the ROS induced the increase in the Trx and Prx activities. Prx and Trx can also participate in the formation of stress respons as acceptors and transducers of the redox signals. Increase in the activity of these enzymes primarily aimed at increasing of the total antioxidant activity in the cells to prevent of the plant to development of oxidative degradation by ROS.

Early-developmental stress, repeatability, and canalization in a suite of physiological and behavioral traits in female zebra finches.

PubMed

Careau, Vincent; Buttemer, William A; Buchanan, Katherine L

2014-10-01

Adaptive developmental plasticity allows individuals experiencing poor environmental conditions in early life to adjust their life-history strategy in order to prioritize short-term fitness benefits and maximize reproductive output in challenging environments. Much research has been conducted to test whether such adoption of a "faster" life-history strategy is accompanied by concordant changes in behavior and physiology, with mixed results. As research in this field has focused on comparison of mean-level responses of treatment groups, few studies include repeated measures of response variables and the effect that developmental stress may have on repeatability per se. We investigated how early-developmental stress affects the mean expression of (and repeatability in) a variety of behavioral and physiological traits in female zebra finches. We predicted that: (1) individuals subjected to nutritional restriction in the nestling phase would have higher feeding and activity rates, with associated increases in hematocrit and basal metabolic rates (BMRs), (2) nutritional restriction in early life would alter adults' stress-induced corticosterone level, and (3) developmental stress would, respectively, influence the amount of among-individual and within-individual variation in behavioral and physiological traits, hence affecting the repeatability of these traits. In comparison to control females, stressed females did not differ in activity rate or stress-induced corticosterone level, but they did have higher levels of feeding, hematocrit, and BMR. Among-individual variance and repeatability were generally higher in stressed females than in controls. Finally, we found that developmental dietary restriction significantly reduced the amount of within-individual variance both in activity rate in the novel environment and in stress-induced corticosterone level. Our results not only confirm previous findings on the effect of early-developmental stress on BMR, but also extend

Close-range hyperspectral image analysis for the early detection of stress responses in individual plants in a high-throughput phenotyping platform

NASA Astrophysics Data System (ADS)

Mohd Asaari, Mohd Shahrimie; Mishra, Puneet; Mertens, Stien; Dhondt, Stijn; Inzé, Dirk; Wuyts, Nathalie; Scheunders, Paul

2018-04-01

The potential of close-range hyperspectral imaging (HSI) as a tool for detecting early drought stress responses in plants grown in a high-throughput plant phenotyping platform (HTPPP) was explored. Reflectance spectra from leaves in close-range imaging are highly influenced by plant geometry and its specific alignment towards the imaging system. This induces high uninformative variability in the recorded signals, whereas the spectral signature informing on plant biological traits remains undisclosed. A linear reflectance model that describes the effect of the distance and orientation of each pixel of a plant with respect to the imaging system was applied. By solving this model for the linear coefficients, the spectra were corrected for the uninformative illumination effects. This approach, however, was constrained by the requirement of a reference spectrum, which was difficult to obtain. As an alternative, the standard normal variate (SNV) normalisation method was applied to reduce this uninformative variability. Once the envisioned illumination effects were eliminated, the remaining differences in plant spectra were assumed to be related to changes in plant traits. To distinguish the stress-related phenomena from regular growth dynamics, a spectral analysis procedure was developed based on clustering, a supervised band selection, and a direct calculation of a spectral similarity measure against a reference. To test the significance of the discrimination between healthy and stressed plants, a statistical test was conducted using a one-way analysis of variance (ANOVA) technique. The proposed analysis techniques was validated with HSI data of maize plants (Zea mays L.) acquired in a HTPPP for early detection of drought stress in maize plant. Results showed that the pre-processing of reflectance spectra with the SNV effectively reduces the variability due to the expected illumination effects. The proposed spectral analysis method on the normalized spectra successfully

Effects of stress in early life on immune functions in rats with asthma and the effects of music therapy.

PubMed

Lu, Yanxia; Liu, Meng; Shi, Shousen; Jiang, Hong; Yang, Lejin; Liu, Xin; Zhang, Qian; Pan, Fang

2010-06-01

Although studies have shown that psychological stress has detrimental effects on bronchial asthma, there are few objective data on whether early-life stress, as early postnatal psychosocial environment, has a long-lasting effect on adult asthma and the potential pathophysiologic mechanism. This study aims to examine the effects on immune function and hypothalamic-pituitary-adrenal (HPA) axis responses in adult asthmatic rats that experienced stress in early life and the potential ameliorative effects of music therapy on these parameters. Forty male Wistar rat pups were randomly assigned to the asthma group, the adulthood-stressed asthma group, the childhood-stressed asthma group, the music group, and the control group. Restraint stress and Mozart's Sonata K.448 were applied to ovalbumin (OVA)-induced asthmatic rats to establish psychological stress and music therapy models. The levels of serum corticosterone were examined in both childhood after stress and adulthood after OVA challenge. Immune indicators in blood, lung, and brain tissues were measured after the last OVA challenge. Stress in both childhood and adulthood resulted in increases in leukocyte and eosinophil numbers and serum interleukin (IL)-4 levels. The adulthood-stressed group demonstrated increased corticosterone levels after challenge, whereas the childhood-stressed group showed increased corticosterone concentration in childhood but decreased level in adulthood. Central IL-1beta exhibited a similar tendency. Music group rats showed reduced serum IL-4 and corticosterone. Stress in childhood and adulthood resulted in different HPA axis responsiveness in the exacerbation of markers of asthma. These data provide the first evidence of the long-term normalizing effects of music on asthmatic rats.

Neonatal overfeeding disrupts pituitary ghrelin signalling in female rats long-term; Implications for the stress response.

PubMed

Sominsky, Luba; Ziko, Ilvana; Spencer, Sarah J

2017-01-01

The hypothalamic-pituitary-adrenal (HPA) axis responses to psychological stress are exacerbated in adult female but not male rats made obese due to overfeeding in early life. Ghrelin, traditionally known for its role in energy homeostasis, has been recently recognised for its role in coordinating the HPA responses to stress, particularly by acting directly at the anterior pituitary where the growth hormone secretagogue receptor (GHSR), the receptor for acyl ghrelin, is abundantly expressed. We therefore hypothesised that neonatal overfeeding in female rats would compromise pituitary responsiveness to ghrelin, contributing to a hyperactive central stress responsiveness. Unlike in males where hypothalamic ghrelin signalling is compromised by neonatal overfeeding, there was no effect of early life diet on circulating ghrelin or hypothalamic ghrelin signalling in females, indicating hypothalamic feeding and metabolic ghrelin circuitry remains intact. However, neonatal overfeeding did lead to long-term alterations in the pituitary ghrelin system. The neonatally overfed females had increased neonatal and reduced adult expression of GHSR and ghrelin-O-acyl transferase (GOAT) in the pituitary as well as reduced pituitary responsiveness to exogenous acyl ghrelin-induced adrenocorticotropic hormone (ACTH) release in vitro. These data suggest that neonatal overfeeding dysregulates pituitary ghrelin signalling long-term in females, potentially accounting for the hyper-responsive HPA axis in these animals. These findings have implications for how females may respond to stress throughout life, suggesting the way ghrelin modifies the stress response at the level of the pituitary may be less efficient in the neonatally overfed.

Deciphering early events involved in hyperosmotic stress-induced programmed cell death in tobacco BY-2 cells.

PubMed

Monetti, Emanuela; Kadono, Takashi; Tran, Daniel; Azzarello, Elisa; Arbelet-Bonnin, Delphine; Biligui, Bernadette; Briand, Joël; Kawano, Tomonori; Mancuso, Stefano; Bouteau, François

2014-03-01

Hyperosmotic stresses represent one of the major constraints that adversely affect plants growth, development, and productivity. In this study, the focus was on early responses to hyperosmotic stress- (NaCl and sorbitol) induced reactive oxygen species (ROS) generation, cytosolic Ca(2+) concentration ([Ca(2+)]cyt) increase, ion fluxes, and mitochondrial potential variations, and on their links in pathways leading to programmed cell death (PCD). By using BY-2 tobacco cells, it was shown that both NaCl- and sorbitol-induced PCD seemed to be dependent on superoxide anion (O2·(-)) generation by NADPH-oxidase. In the case of NaCl, an early influx of sodium through non-selective cation channels participates in the development of PCD through mitochondrial dysfunction and NADPH-oxidase-dependent O2·(-) generation. This supports the hypothesis of different pathways in NaCl- and sorbitol-induced cell death. Surprisingly, other shared early responses, such as [Ca(2+)]cyt increase and singlet oxygen production, do not seem to be involved in PCD.

Early and delayed long-term transcriptional changes and short-term transient responses during cold acclimation in olive leaves

PubMed Central

Leyva-Pérez, María de la O; Valverde-Corredor, Antonio; Valderrama, Raquel; Jiménez-Ruiz, Jaime; Muñoz-Merida, Antonio; Trelles, Oswaldo; Barroso, Juan Bautista; Mercado-Blanco, Jesús; Luque, Francisco

2015-01-01

Low temperature severely affects plant growth and development. To overcome this constraint, several plant species from regions having a cool season have evolved an adaptive response, called cold acclimation. We have studied this response in olive tree (Olea europaea L.) cv. Picual. Biochemical stress markers and cold-stress symptoms were detected after the first 24 h as sagging leaves. After 5 days, the plants were found to have completely recovered. Control and cold-stressed plants were sequenced by Illumina HiSeq 1000 paired-end technique. We also assembled a new olive transcriptome comprising 157,799 unigenes and found 6,309 unigenes differentially expressed in response to cold. Three types of response that led to cold acclimation were found: short-term transient response, early long-term response, and late long-term response. These subsets of unigenes were related to different biological processes. Early responses involved many cold-stress-responsive genes coding for, among many other things, C-repeat binding factor transcription factors, fatty acid desaturases, wax synthesis, and oligosaccharide metabolism. After long-term exposure to cold, a large proportion of gene down-regulation was found, including photosynthesis and plant growth genes. Up-regulated genes after long-term cold exposure were related to organelle fusion, nucleus organization, and DNA integration, including retrotransposons. PMID:25324298

Shear stress upregulates regeneration-related immediate early genes in liver progenitors in 3D ECM-like microenvironments.

PubMed

Nishii, Kenichiro; Brodin, Erik; Renshaw, Taylor; Weesner, Rachael; Moran, Emma; Soker, Shay; Sparks, Jessica L

2018-05-01

The role of fluid stresses in activating the hepatic stem/progenitor cell regenerative response is not well understood. This study hypothesized that immediate early genes (IEGs) with known links to liver regeneration will be upregulated in liver progenitor cells (LPCs) exposed to in vitro shear stresses on the order of those produced from elevated interstitial flow after partial hepatectomy. The objectives were: (1) to develop a shear flow chamber for application of fluid stress to LPCs in 3D culture; and (2) to determine the effects of fluid stress on IEG expression in LPCs. Two hours of shear stress exposure at ∼4 dyn/cm 2 was applied to LPCs embedded individually or as 3D spheroids within a hyaluronic acid/collagen I hydrogel. Results were compared against static controls. Quantitative reverse transcriptase polymerase chain reaction was used to evaluate the effect of experimental treatments on gene expression. Twenty-nine genes were analyzed, including IEGs and other genes linked to liver regeneration. Four IEGs (CFOS, IP10, MKP1, ALB) and three other regeneration-related genes (WNT, VEGF, EpCAM) were significantly upregulated in LPCs in response to fluid mechanical stress. LPCs maintained an early to intermediate stage of differentiation in spheroid culture in the absence of the hydrogel, and addition of the gel initiated cholangiocyte differentiation programs which were abrogated by the onset of flow. Collectively the flow-upregulated genes fit the pattern of an LPC-mediated proliferative/regenerative response. These results suggest that fluid stresses are potentially important regulators of the LPC-mediated regeneration response in liver. © 2017 Wiley Periodicals, Inc.

Early life stress determines the effects of glucocorticoids and stress on hippocampal function: Electrophysiological and behavioral evidence respectively.

PubMed

Pillai, Anup G; Arp, Marit; Velzing, Els; Lesuis, Sylvie L; Schmidt, Mathias V; Holsboer, Florian; Joëls, Marian; Krugers, Harm J

2018-05-01

Exposure to early-life adversity may program brain function to prepare individuals for adaptation to matching environmental contexts. In this study we tested this hypothesis in more detail by examining the effects of early-life stress - induced by raising offspring with limited nesting and bedding material from postnatal days 2-9 - in various behavioral tasks and on synaptic function in adult mice. Early-life stress impaired adult performance in the hippocampal dependent low-arousing object-in-context recognition memory task. This effect was absent when animals were exposed to a single stressor before training. Early-life stress did not alter high-arousing context and auditory fear conditioning. Early-life stress-induced behavioral modifications were not associated with alterations in the dendritic architecture of hippocampal CA1 pyramidal neurons or principal neurons of the basolateral amygdala. However, early-life stress reduced the ratio of NMDA to AMPA receptor-mediated excitatory postsynaptic currents and glutamate release probability specifically in hippocampal CA1 neurons, but not in the basolateral amygdala. These ex vivo effects in the hippocampus were abolished by acute glucocorticoid treatment. Our findings support that early-life stress can hamper object-in-context learning via pre- and postsynaptic mechanisms that affect hippocampal function but these effects are counteracted by acute stress or elevated glucocorticoid levels. Copyright © 2018. Published by Elsevier Ltd.

SALT-RESPONSIVE ERF1 Regulates Reactive Oxygen Species–Dependent Signaling during the Initial Response to Salt Stress in Rice[W

PubMed Central

Schmidt, Romy; Mieulet, Delphine; Hubberten, Hans-Michael; Obata, Toshihiro; Hoefgen, Rainer; Fernie, Alisdair R.; Fisahn, Joachim; San Segundo, Blanca; Guiderdoni, Emmanuel; Schippers, Jos H.M.; Mueller-Roeber, Bernd

2013-01-01

Early detection of salt stress is vital for plant survival and growth. Still, the molecular processes controlling early salt stress perception and signaling are not fully understood. Here, we identified SALT-RESPONSIVE ERF1 (SERF1), a rice (Oryza sativa) transcription factor (TF) gene that shows a root-specific induction upon salt and hydrogen peroxide (H2O2) treatment. Loss of SERF1 impairs the salt-inducible expression of genes encoding members of a mitogen-activated protein kinase (MAPK) cascade and salt tolerance–mediating TFs. Furthermore, we show that SERF1-dependent genes are H2O2 responsive and demonstrate that SERF1 binds to the promoters of MAPK KINASE KINASE6 (MAP3K6), MAPK5, DEHYDRATION-RESPONSIVE ELEMENT BINDING2A (DREB2A), and ZINC FINGER PROTEIN179 (ZFP179) in vitro and in vivo. SERF1 also directly induces its own gene expression. In addition, SERF1 is a phosphorylation target of MAPK5, resulting in enhanced transcriptional activity of SERF1 toward its direct target genes. In agreement, plants deficient for SERF1 are more sensitive to salt stress compared with the wild type, while constitutive overexpression of SERF1 improves salinity tolerance. We propose that SERF1 amplifies the reactive oxygen species–activated MAPK cascade signal during the initial phase of salt stress and translates the salt-induced signal into an appropriate expressional response resulting in salt tolerance. PMID:23800963

Predictors of responses to stress among families coping with poverty-related stress.

PubMed

Santiago, Catherine DeCarlo; Etter, Erica Moran; Wadsworth, Martha E; Raviv, Tali

2012-05-01

This study tested how poverty-related stress (PRS), psychological distress, and responses to stress predicted future effortful coping and involuntary stress responses one year later. In addition, we explored age, sex, ethnicity, and parental influences on responses to stress over time. Hierarchical linear modeling analyses conducted with 98 low-income families (300 family members: 136 adults, 82 school-aged children, 82 adolescents) revealed that primary control coping, secondary control coping, disengagement, involuntary engagement, and involuntary disengagement each significantly predicted future use of that response. Primary and secondary control coping also predicted less maladaptive future responses to stress, while involuntary responses to stress undermined the development of adaptive responding. Age, sex, and interactions among PRS and prior coping were also found to predict certain responses to stress. In addition, child subgroup analyses demonstrate the importance of parental modeling of coping and involuntary stress responses, and warmth/nurturance and monitoring practices. Results are discussed with regard to the implications for preventive interventions with families in poverty.

Transactional relations between caregiving stress, executive functioning, and problem behavior from early childhood to early adolescence

PubMed Central

LaGasse, Linda L.; Conradt, Elisabeth; Karalunas, Sarah L.; Dansereau, Lynne M.; Butner, Jonathan E.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles R.; Whitaker, Toni M.; Lester, Barry M.

2016-01-01

Developmental psychopathologists face the difficult task of identifying the environmental conditions that may contribute to early childhood behavior problems. Highly stressed caregivers can exacerbate behavior problems, while children with behavior problems may make parenting more difficult and increase caregiver stress. Unknown is: (1) how these transactions originate, (2) whether they persist over time to contribute to the development of problem behavior and (3) what role resilience factors, such as child executive functioning, may play in mitigating the development of problem behavior. In the present study, transactional relations between caregiving stress, executive functioning, and behavior problems were examined in a sample of 1,388 children with prenatal drug exposures at three developmental time points: early childhood (birth-age 5), middle childhood (ages 6 to 9), and early adolescence (ages 10 to 13). Transactional relations differed between caregiving stress and internalizing versus externalizing behavior. Targeting executive functioning in evidence-based interventions for children with prenatal substance exposure who present with internalizing problems and treating caregiving psychopathology, depression, and parenting stress in early childhood may be particularly important for children presenting with internalizing behavior. PMID:27427803

Anthocyanins of Coloured Wheat Genotypes in Specific Response to SalStress.

PubMed

Mbarki, Sonia; Sytar, Oksana; Zivcak, Marek; Abdelly, Chedly; Cerda, Artemio; Brestic, Marian

2018-06-23

The present study investigated the effect of salt stress on the development of adaptive responses and growth parameters of different coloured wheat genotypes. The different coloured wheat genotypes have revealed variation in the anthocyanin content, which may affect the development of adaptive responses under increasing salinity stress. In the early stage of treatment with salt at a lower NaCl concentration (100 mM), anthocyanins and proline accumulate, which shows rapid development of the stress reaction. A dose-dependent increase in flavonol content was observed for wheat genotypes with more intense purple-blue pigmentation after treatment with 150 mM and 200 mM NaCl. The content of Na⁺ and K⁺ obtained at different levels of salinity based on dry weight (DW) was more than 3 times greater than the control, with a significant increase of both ions under salt stress. Overall, our results demonstrated that coloured wheat genotypes with high anthocyanin content are able to maintain significantly higher dry matter production after salt stress treatment.

TPH-2 Polymorphisms Interact with Early Life Stress to Influence Response to Treatment with Antidepressant Drugs.

PubMed

Xu, Zhi; Reynolds, Gavin P; Yuan, Yonggui; Shi, Yanyan; Pu, Mengjia; Zhang, Zhijun

2016-11-01

Variation in genes implicated in monoamine neurotransmission may interact with environmental factors to influence antidepressant response. We aimed to determine how a range of single nucleotide polymorphisms in monoaminergic genes influence this response to treatment and how they interact with childhood trauma and recent life stress in a Chinese sample. An initial study of monoaminergic coding region single nucleotide polymorphisms identified significant associations of TPH2 and HTR1B single nucleotide polymorphisms with treatment response that showed interactions with childhood and recent life stress, respectively (Xu et al., 2012). A total of 47 further single nucleotide polymorphisms in 17 candidate monoaminergic genes were genotyped in 281 Chinese Han patients with major depressive disorder. Response to 6 weeks' antidepressant treatment was determined by change in the 17-item Hamilton Depression Rating Scale score, and previous stressful events were evaluated by the Life Events Scale and Childhood Trauma Questionnaire-Short Form. Three TPH2 single nucleotide polymorphisms (rs11178998, rs7963717, and rs2171363) were significantly associated with antidepressant response in this Chinese sample, as was a haplotype in TPH2 (rs2171363 and rs1487278). One of these, rs2171363, showed a significant interaction with childhood adversity in its association with antidepressant response. These findings provide further evidence that variation in TPH2 is associated with antidepressant response and may also interact with childhood trauma to influence outcome of antidepressant treatment. © The Author 2016. Published by Oxford University Press on behalf of CINP.

TPH-2 Polymorphisms Interact with Early Life Stress to Influence Response to Treatment with Antidepressant Drugs

PubMed Central

Reynolds, Gavin P.; Yuan, Yonggui; Shi, Yanyan; Pu, Mengjia; Zhang, Zhijun

2016-01-01

Background: Variation in genes implicated in monoamine neurotransmission may interact with environmental factors to influence antidepressant response. We aimed to determine how a range of single nucleotide polymorphisms in monoaminergic genes influence this response to treatment and how they interact with childhood trauma and recent life stress in a Chinese sample. An initial study of monoaminergic coding region single nucleotide polymorphisms identified significant associations of TPH2 and HTR1B single nucleotide polymorphisms with treatment response that showed interactions with childhood and recent life stress, respectively (Xu et al., 2012). Methods: A total of 47 further single nucleotide polymorphisms in 17 candidate monoaminergic genes were genotyped in 281 Chinese Han patients with major depressive disorder. Response to 6 weeks’ antidepressant treatment was determined by change in the 17-item Hamilton Depression Rating Scale score, and previous stressful events were evaluated by the Life Events Scale and Childhood Trauma Questionnaire-Short Form. Results: Three TPH2 single nucleotide polymorphisms (rs11178998, rs7963717, and rs2171363) were significantly associated with antidepressant response in this Chinese sample, as was a haplotype in TPH2 (rs2171363 and rs1487278). One of these, rs2171363, showed a significant interaction with childhood adversity in its association with antidepressant response. Conclusions: These findings provide further evidence that variation in TPH2 is associated with antidepressant response and may also interact with childhood trauma to influence outcome of antidepressant treatment. PMID:27521242

Motivation, stress, anxiety, and cortisol responses in elite paragliders.

PubMed

Filaire, Edith; Alix, Deborah; Rouveix, Matthieu; Le Scanff, Christine

2007-06-01

In this study metamotivational dominance (measured with the Telic Dominance Scale), precompetition anxiety (evaluated with the CSAI-2), perceived stress (measured with the Perceived Stress Scale), and cortisol responses by 10 paragliding competitors prior to and following a paragliding competition were examined. Saliva was collected for each subject for cortisol analysis on eight occasions: during a resting day (baseline values) and prior to and after competition. Analysis indicated subjects were all paratelic-dominant (characterized by a desire for high arousal, a focus on the present). Scores were high on the Perceived Stress Scale and cognitive nxiety (a telic emotion). Cortisol values showed a significant increase early on the day of the competition and remained elevated all the day, with highest concentrations at the start. Participants' cognitive anxiety and cortisol responses were significantly correlated .79 just before the jump and the direction of the cognitive anxiety was rated as facilitative of performance. These results may suggest that the more frequently the subject is playful in life, the more cortisol they produce when aroused in a less frequent telic state.

FoxO and Stress Responses in the Cnidarian Hydra vulgaris

PubMed Central

Bridge, Diane; Theofiles, Alexander G.; Holler, Rebecca L.; Marcinkevicius, Emily; Steele, Robert E.; Martínez, Daniel E.

2010-01-01

Background In the face of changing environmental conditions, the mechanisms underlying stress responses in diverse organisms are of increasing interest. In vertebrates, Drosophila, and Caenorhabditis elegans, FoxO transcription factors mediate cellular responses to stress, including oxidative stress and dietary restriction. Although FoxO genes have been identified in early-arising animal lineages including sponges and cnidarians, little is known about their roles in these organisms. Methods/Principal Findings We have examined the regulation of FoxO activity in members of the well-studied cnidarian genus Hydra. We find that Hydra FoxO is expressed at high levels in cells of the interstitial lineage, a cell lineage that includes multipotent stem cells that give rise to neurons, stinging cells, secretory cells and gametes. Using transgenic Hydra that express a FoxO-GFP fusion protein in cells of the interstitial lineage, we have determined that heat shock causes localization of the fusion protein to the nucleus. Our results also provide evidence that, as in bilaterian animals, Hydra FoxO activity is regulated by both Akt and JNK kinases. Conclusions These findings imply that basic mechanisms of FoxO regulation arose before the evolution of bilaterians and raise the possibility that FoxO is involved in stress responses of other cnidarian species, including corals. PMID:20657733

FoxO and stress responses in the cnidarian Hydra vulgaris.

PubMed

Bridge, Diane; Theofiles, Alexander G; Holler, Rebecca L; Marcinkevicius, Emily; Steele, Robert E; Martínez, Daniel E

2010-07-21

In the face of changing environmental conditions, the mechanisms underlying stress responses in diverse organisms are of increasing interest. In vertebrates, Drosophila, and Caenorhabditis elegans, FoxO transcription factors mediate cellular responses to stress, including oxidative stress and dietary restriction. Although FoxO genes have been identified in early-arising animal lineages including sponges and cnidarians, little is known about their roles in these organisms. We have examined the regulation of FoxO activity in members of the well-studied cnidarian genus Hydra. We find that Hydra FoxO is expressed at high levels in cells of the interstitial lineage, a cell lineage that includes multipotent stem cells that give rise to neurons, stinging cells, secretory cells and gametes. Using transgenic Hydra that express a FoxO-GFP fusion protein in cells of the interstitial lineage, we have determined that heat shock causes localization of the fusion protein to the nucleus. Our results also provide evidence that, as in bilaterian animals, Hydra FoxO activity is regulated by both Akt and JNK kinases. These findings imply that basic mechanisms of FoxO regulation arose before the evolution of bilaterians and raise the possibility that FoxO is involved in stress responses of other cnidarian species, including corals.

Alprazolam treatment immediately after stress exposure interferes with the normal HPA-stress response and increases vulnerability to subsequent stress in an animal model of PTSD.

PubMed

Matar, Michael A; Zohar, Joseph; Kaplan, Zeev; Cohen, Hagit

2009-04-01

In light of clinical reports suggesting that early benzodiazepine administration interferes with long-term recovery from traumatic stress, a prospective animal model for PTSD was employed to assess the short- and long-term effects of a brief course of alprazolam following stress exposure. Animals exposed to stress were treated either 1 h or 7 days later with alprazolam or vehicle for 3-days. Outcome measures included behavior in the elevated plus-maze (EPM) and acoustic startle response (ASR) tests 30 days after initial exposure and freezing behavior upon exposure to a trauma-cue on day 31. One group was repeatedly exposed to the triggering trauma shortly before and after treatment and assessed as above. Circulating corticosterone levels were assessed 4 h after initiation of alprazolam and post-treatment. Pre-set cut-off behavioral criteria classified exposed animals according to their EPM and ASR response-patterns into 'extreme', 'minimal,' or 'partial' behavioral response for analysis of prevalence rates. Immediate alprazolam treatment was effective in alleviating anxiety at day 4. No observable anxiolytic effects remained at day 30. Immediate alprazolam also resulted in significantly greater freezing response to trauma-cue exposure and in extreme responses to double-exposure. Corticosterone levels were significantly suppressed by alprazolam during treatment and rebounded after cessation. A brief course of alprazolam in the immediate aftermath of stress-exposure is associated with less favorable responses to additional stress-exposure later on. Alprazolam was associated with a significant attenuation of the HPA-response, suggesting a possible link between initial HPA-axis response disruption and the subsequent unfavorable outcomes.

Early Life Stress Effects on Glucocorticoid—BDNF Interplay in the Hippocampus

PubMed Central

Daskalakis, Nikolaos P.; De Kloet, Edo Ronald; Yehuda, Rachel; Malaspina, Dolores; Kranz, Thorsten M.

2015-01-01

Early life stress (ELS) is implicated in the etiology of multiple psychiatric disorders. Important biological effects of ELS are manifested in stress-susceptible regions of the hippocampus and are partially mediated by long-term effects on glucocorticoid (GC) and/or neurotrophin signaling pathways. GC-signaling mediates the regulation of stress response to maintain homeostasis, while neurotrophin signaling plays a key role in neuronal outgrowth and is crucial for axonal guidance and synaptic integrity. The neurotrophin and GC-signaling pathways co-exist throughout the central nervous system (CNS), particularly in the hippocampus, which has high expression levels of glucocorticoid-receptors (GR) and mineralocorticoid-receptors (MR) as well as brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related kinase receptor B (TrkB). This review addresses the effects of ELS paradigms on GC- and BDNF-dependent mechanisms and their crosstalk in the hippocampus, including potential implications for the pathogenesis of common stress-related disorders. PMID:26635521

Rate of rise in diastolic blood pressure influences vascular sympathetic response to mental stress.

PubMed

El Sayed, Khadigeh; Macefield, Vaughan G; Hissen, Sarah L; Joyner, Michael J; Taylor, Chloe E

2016-12-15

Research indicates that individuals may experience a rise (positive responders) or fall (negative responders) in muscle sympathetic nerve activity (MSNA) during mental stress. In this study, we examined the early blood pressure responses (including the peak, time of peak and rate of rise in blood pressure) to mental stress in positive and negative responders. Negative MSNA responders to mental stress exhibit a more rapid rise in diastolic pressure at the onset of the stressor, suggesting a baroreflex-mediated suppression of MSNA. In positive responders there is a more sluggish rise in blood pressure during mental stress, which appears to be MSNA-driven. This study suggests that whether MSNA has a role in the pressor response is dependent upon the reactivity of blood pressure early in the task. Research indicates that individuals may experience a rise (positive responders) or fall (negative responders) in muscle sympathetic nerve activity (MSNA) during mental stress. The aim was to examine the early blood pressure response to stress in positive and negative responders and thus its influence on the direction of change in MSNA. Blood pressure and MSNA were recorded continuously in 21 healthy young males during 2 min mental stressors (mental arithmetic, Stroop test) and physical stressors (cold pressor, handgrip exercise, post-exercise ischaemia). Participants were classified as negative or positive responders according to the direction of the mean change in MSNA during the stressor tasks. The peak changes, time of peak and rate of changes in blood pressure were compared between groups. During mental arithmetic negative responders experienced a significantly greater rate of rise in diastolic blood pressure in the first minute of the task (1.3 ± 0.5 mmHg s -1 ) compared with positive responders (0.4 ± 0.1 mmHg s -1 ; P = 0.03). Similar results were found for the Stroop test. Physical tasks elicited robust parallel increases in blood pressure and MSNA across

Rate of rise in diastolic blood pressure influences vascular sympathetic response to mental stress

PubMed Central

El Sayed, Khadigeh; Macefield, Vaughan G.; Hissen, Sarah L.; Joyner, Michael J.

2016-01-01

Key points Research indicates that individuals may experience a rise (positive responders) or fall (negative responders) in muscle sympathetic nerve activity (MSNA) during mental stress.In this study, we examined the early blood pressure responses (including the peak, time of peak and rate of rise in blood pressure) to mental stress in positive and negative responders.Negative MSNA responders to mental stress exhibit a more rapid rise in diastolic pressure at the onset of the stressor, suggesting a baroreflex‐mediated suppression of MSNA. In positive responders there is a more sluggish rise in blood pressure during mental stress, which appears to be MSNA‐driven.This study suggests that whether MSNA has a role in the pressor response is dependent upon the reactivity of blood pressure early in the task. Abstract Research indicates that individuals may experience a rise (positive responders) or fall (negative responders) in muscle sympathetic nerve activity (MSNA) during mental stress. The aim was to examine the early blood pressure response to stress in positive and negative responders and thus its influence on the direction of change in MSNA. Blood pressure and MSNA were recorded continuously in 21 healthy young males during 2 min mental stressors (mental arithmetic, Stroop test) and physical stressors (cold pressor, handgrip exercise, post‐exercise ischaemia). Participants were classified as negative or positive responders according to the direction of the mean change in MSNA during the stressor tasks. The peak changes, time of peak and rate of changes in blood pressure were compared between groups. During mental arithmetic negative responders experienced a significantly greater rate of rise in diastolic blood pressure in the first minute of the task (1.3 ± 0.5 mmHg s−1) compared with positive responders (0.4 ± 0.1 mmHg s−1; P = 0.03). Similar results were found for the Stroop test. Physical tasks elicited robust parallel increases in blood

Neonatal overfeeding disrupts pituitary ghrelin signalling in female rats long-term; Implications for the stress response

PubMed Central

Ziko, Ilvana; Spencer, Sarah J.

2017-01-01

The hypothalamic-pituitary-adrenal (HPA) axis responses to psychological stress are exacerbated in adult female but not male rats made obese due to overfeeding in early life. Ghrelin, traditionally known for its role in energy homeostasis, has been recently recognised for its role in coordinating the HPA responses to stress, particularly by acting directly at the anterior pituitary where the growth hormone secretagogue receptor (GHSR), the receptor for acyl ghrelin, is abundantly expressed. We therefore hypothesised that neonatal overfeeding in female rats would compromise pituitary responsiveness to ghrelin, contributing to a hyperactive central stress responsiveness. Unlike in males where hypothalamic ghrelin signalling is compromised by neonatal overfeeding, there was no effect of early life diet on circulating ghrelin or hypothalamic ghrelin signalling in females, indicating hypothalamic feeding and metabolic ghrelin circuitry remains intact. However, neonatal overfeeding did lead to long-term alterations in the pituitary ghrelin system. The neonatally overfed females had increased neonatal and reduced adult expression of GHSR and ghrelin-O-acyl transferase (GOAT) in the pituitary as well as reduced pituitary responsiveness to exogenous acyl ghrelin-induced adrenocorticotropic hormone (ACTH) release in vitro. These data suggest that neonatal overfeeding dysregulates pituitary ghrelin signalling long-term in females, potentially accounting for the hyper-responsive HPA axis in these animals. These findings have implications for how females may respond to stress throughout life, suggesting the way ghrelin modifies the stress response at the level of the pituitary may be less efficient in the neonatally overfed. PMID:28282447

RNA-seq Analysis of Early Hepatic Response to Handling and Confinement Stress in Rainbow Trout

PubMed Central

Liu, Sixin; Gao, Guangtu; Palti, Yniv; Cleveland, Beth M.; Weber, Gregory M.; Rexroad, Caird E.

2014-01-01

Fish under intensive rearing conditions experience various stressors which have negative impacts on survival, growth, reproduction and fillet quality. Identifying and characterizing the molecular mechanisms underlying stress responses will facilitate the development of strategies that aim to improve animal welfare and aquaculture production efficiency. In this study, we used RNA-seq to identify transcripts which are differentially expressed in the rainbow trout liver in response to handling and confinement stress. These stressors were selected due to their relevance in aquaculture production. Total RNA was extracted from the livers of individual fish in five tanks having eight fish each, including three tanks of fish subjected to a 3 hour handling and confinement stress and two control tanks. Equal amount of total RNA of six individual fish was pooled by tank to create five RNA-seq libraries which were sequenced in one lane of Illumina HiSeq 2000. Three sequencing runs were conducted to obtain a total of 491,570,566 reads which were mapped onto the previously generated stress reference transcriptome to identify 316 differentially expressed transcripts (DETs). Twenty one DETs were selected for qPCR to validate the RNA-seq approach. The fold changes in gene expression identified by RNA-seq and qPCR were highly correlated (R2 = 0.88). Several gene ontology terms including transcription factor activity and biological process such as glucose metabolic process were enriched among these DETs. Pathways involved in response to handling and confinement stress were implicated by mapping the DETs to reference pathways in the KEGG database. Accession Numbers Raw RNA-seq reads have been submitted to the NCBI Short Read Archive under accession number SRP022881. Customized Perl Scripts All customized scripts described in this paper are available from Dr. Guangtu Gao or the corresponding author. PMID:24558395

Early life trauma exposure and stress sensitivity in young children.

PubMed

Grasso, Damion J; Ford, Julian D; Briggs-Gowan, Margaret J

2013-01-01

The current study replicates and extends work with adults that highlights the relationship between trauma exposure and distress in response to subsequent, nontraumatic life stressors. The sample included 213 2-4-year-old children in which 64.3% had a history of potential trauma exposure. Children were categorized into 4 groups based on trauma history and current life stress. In a multivariate analysis of variance, trauma-exposed children with current life stressors had elevated internalizing and externalizing problems compared with trauma-exposed children without current stress and nontrauma-exposed children with and without current stressors. The trauma-exposed groups with or without current stressors did not differ on posttraumatic stress disorder symptom severity. Accounting for number of traumatic events did not change these results. These findings suggest that early life trauma exposure may sensitize young children and place them at risk for internalizing or externalizing problems when exposed to subsequent, nontraumatic life stressors.

Early and delayed long-term transcriptional changes and short-term transient responses during cold acclimation in olive leaves.

PubMed

Leyva-Pérez, María de la O; Valverde-Corredor, Antonio; Valderrama, Raquel; Jiménez-Ruiz, Jaime; Muñoz-Merida, Antonio; Trelles, Oswaldo; Barroso, Juan Bautista; Mercado-Blanco, Jesús; Luque, Francisco

2015-02-01

Low temperature severely affects plant growth and development. To overcome this constraint, several plant species from regions having a cool season have evolved an adaptive response, called cold acclimation. We have studied this response in olive tree (Olea europaea L.) cv. Picual. Biochemical stress markers and cold-stress symptoms were detected after the first 24 h as sagging leaves. After 5 days, the plants were found to have completely recovered. Control and cold-stressed plants were sequenced by Illumina HiSeq 1000 paired-end technique. We also assembled a new olive transcriptome comprising 157,799 unigenes and found 6,309 unigenes differentially expressed in response to cold. Three types of response that led to cold acclimation were found: short-term transient response, early long-term response, and late long-term response. These subsets of unigenes were related to different biological processes. Early responses involved many cold-stress-responsive genes coding for, among many other things, C-repeat binding factor transcription factors, fatty acid desaturases, wax synthesis, and oligosaccharide metabolism. After long-term exposure to cold, a large proportion of gene down-regulation was found, including photosynthesis and plant growth genes. Up-regulated genes after long-term cold exposure were related to organelle fusion, nucleus organization, and DNA integration, including retrotransposons. © The Author 2014. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Early Life Stress Affects Mortality Rate More than Social Behavior, Gene Expression or Oxidative Damage in Honey Bee Workers

PubMed Central

Rueppell, Olav; Yousefi, Babak; Collazo, Juan; Smith, Daniel

2017-01-01

Early life stressors can affect aging and life expectancy in positive or negative ways. Individuals can adjust their behavior and molecular physiology based on early life experiences but relatively few studies have connected such mechanisms to demographic patterns in social organisms. Sociality buffers individuals from environmental influences and it is unclear how much early life stress affects later life history. Workers of the honey bee (Apis mellifera L.) were exposed to two stressors, Varroa parasitism and paraquat exposure, early in life. Consequences were measured at the molecular, behavioral, and demographic level. While treatments did not significantly affect levels of oxidative damage, expression of select genes, and titers of the common deformed wing virus, most of these measures were affected by age. Some of the age effects, such as declining levels of deformed wing virus and oxidative damage, were opposite to our predictions but may be explained by demographic selection. Further analyses suggested some influences of worker behavior on mortality and indicated weak treatment effects on behavior. The latter effects were inconsistent among the two experiments. However, mortality rate was consistently reduced by Varroa mite stress during development. Thus, mortality was more responsive to early life stress than our other response variables. The lack of treatment effects on these measures may be due to the social organization of honey bees that buffers the individual from the impact of stressful developmental conditions. PMID:28122251

Early life stress affects mortality rate more than social behavior, gene expression or oxidative damage in honey bee workers.

PubMed

Rueppell, Olav; Yousefi, Babak; Collazo, Juan; Smith, Daniel

2017-04-01

Early life stressors can affect aging and life expectancy in positive or negative ways. Individuals can adjust their behavior and molecular physiology based on early life experiences but relatively few studies have connected such mechanisms to demographic patterns in social organisms. Sociality buffers individuals from environmental influences and it is unclear how much early life stress affects later life history. Workers of the honey bee (Apis mellifera L.) were exposed to two stressors, Varroa parasitism and Paraquat exposure, early in life. Consequences were measured at the molecular, behavioral, and demographic level. While treatments did not significantly affect levels of oxidative damage, expression of select genes, and titers of the common deformed wing virus, most of these measures were affected by age. Some of the age effects, such as declining levels of deformed wing virus and oxidative damage, were opposite to our predictions but may be explained by demographic selection. Further analyses suggested some influences of worker behavior on mortality and indicated weak treatment effects on behavior. The latter effects were inconsistent among the two experiments. However, mortality rate was consistently reduced by Varroa mite stress during development. Thus, mortality was more responsive to early life stress than our other response variables. The lack of treatment effects on these measures may be due to the social organization of honey bees that buffers the individual from the impact of stressful developmental conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

The Batten disease gene CLN3 is required for the response to oxidative stress

PubMed Central

Tuxworth, Richard I.; Chen, Haiyang; Vivancos, Valerie; Carvajal, Nancy; Huang, Xun; Tear, Guy

2011-01-01

Mutations in the CLN3 gene cause juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease), an early onset neurodegenerative disorder. JNCL is the most common of the NCLs, a group of disorders with infant or childhood onset that are caused by single gene mutations. The NCLs, although relatively rare, share many pathological and clinical similarities with the more common late-onset neurodegenerative disorders, while their simple genetic basis makes them an excellent paradigm. The early onset and rapid disease progression in the NCLs suggests that one or more key cellular processes are severely compromised. To identify the functional pathways compromised in JNCL, we have performed a gain-of-function modifier screen in Drosophila. We find that CLN3 interacts genetically with the core stress signalling pathways and components of stress granules, suggesting a function in stress responses. In support of this, we find that Drosophila lacking CLN3 function are hypersensitive to oxidative stress yet they respond normally to other physiological stresses. Overexpression of CLN3 is sufficient to confer increased resistance to oxidative stress. We find that CLN3 mutant flies perceive conditions of increased oxidative stress correctly but are unable to detoxify reactive oxygen species, suggesting that their ability to respond is compromised. Together, our data suggest that the lack of CLN3 function leads to a failure to manage the response to oxidative stress and this may be the key deficit in JNCL that leads to neuronal degeneration. PMID:21372148

Long-term academic stress enhances early processing of facial expressions.

PubMed

Zhang, Liang; Qin, Shaozheng; Yao, Zhuxi; Zhang, Kan; Wu, Jianhui

2016-11-01

Exposure to long-term stress can lead to a variety of emotional and behavioral problems. Although widely investigated, the neural basis of how long-term stress impacts emotional processing in humans remains largely elusive. Using event-related brain potentials (ERPs), we investigated the effects of long-term stress on the neural dynamics of emotionally facial expression processing. Thirty-nine male college students undergoing preparation for a major examination and twenty-one matched controls performed a gender discrimination task for faces displaying angry, happy, and neutral expressions. The results of the Perceived Stress Scale showed that participants in the stress group perceived higher levels of long-term stress relative to the control group. ERP analyses revealed differential effects of long-term stress on two early stages of facial expression processing: 1) long-term stress generally augmented posterior P1 amplitudes to facial stimuli irrespective of expression valence, suggesting that stress can increase sensitization to visual inputs in general, and 2) long-term stress selectively augmented fronto-central P2 amplitudes for angry but not for neutral or positive facial expressions, suggesting that stress may lead to increased attentional prioritization to processing negative emotional stimuli. Together, our findings suggest that long-term stress has profound impacts on the early stages of facial expression processing, with an increase at the very early stage of general information inputs and a subsequent attentional bias toward processing emotionally negative stimuli. Copyright © 2016 Elsevier B.V. All rights reserved.

Deciphering early events involved in hyperosmotic stress-induced programmed cell death in tobacco BY-2 cells

PubMed Central

Monetti, Emanuela; Kadono, Takashi; Bouteau, François

2014-01-01

Hyperosmotic stresses represent one of the major constraints that adversely affect plants growth, development, and productivity. In this study, the focus was on early responses to hyperosmotic stress- (NaCl and sorbitol) induced reactive oxygen species (ROS) generation, cytosolic Ca2+ concentration ([Ca2+]cyt) increase, ion fluxes, and mitochondrial potential variations, and on their links in pathways leading to programmed cell death (PCD). By using BY-2 tobacco cells, it was shown that both NaCl- and sorbitol-induced PCD seemed to be dependent on superoxide anion (O2·–) generation by NADPH-oxidase. In the case of NaCl, an early influx of sodium through non-selective cation channels participates in the development of PCD through mitochondrial dysfunction and NADPH-oxidase-dependent O2·– generation. This supports the hypothesis of different pathways in NaCl- and sorbitol-induced cell death. Surprisingly, other shared early responses, such as [Ca2+]cyt increase and singlet oxygen production, do not seem to be involved in PCD. PMID:24420571

Pre-pubertal stress exposure affects adult behavioral response in association with changes in circulating corticosterone and brain-derived neurotrophic factor.

PubMed

Bazak, Noam; Kozlovsky, Nitsan; Kaplan, Zeev; Matar, Michael; Golan, Hava; Zohar, Joseph; Richter-Levin, Gal; Cohen, Hagit

2009-07-01

Early-life stress produces a cascade of neurobiological events that cause enduring changes in neural plasticity and synaptic efficacy that appear to play pivotal roles in the pathophysiology of post-traumatic stress disorder (PTSD). Brain-derived neurotrophic factor (BDNF) has been implicated in the neurobiological mechanisms of these changes, in interaction with components of the stress response, such as corticosterone. This study examined the consequences of juvenile stress for behavior during adulthood in association with circulating corticosterone levels and BDNF expression. The experiments examined single exposure to predator scent stress (soiled cat litter for 10 min) as compared to repeated exposure, early in life and later on. Behavioral responses were assessed in the elevated plus maze and the acoustic startle response paradigms at 28, 60 and 90 days of age. Plasma corticosterone was measured and brain areas analyzed for BDNF levels. The results show that juvenile stress exposure increased anxiety-like behavior and startle amplitude and decreased plasma corticosterone. This response was seen immediately after exposure and also long term. Adult stress exposure increased anxiety-like behavior, startle amplitude and plasma corticosterone. Exposure to both early and later life trauma elicited reduced levels of corticosterone following the initial exposure, which were not raised by re-exposure, and elicited significant downregulation of BDNF mRNA and protein levels in the hippocampus CA1 subregion. The consequences of adult stress exposure were more severe in rats were exposed to the same stressor as juveniles, indicated increased vulnerability. The results suggest that juvenile stress has resounding effects in adulthood reflected in behavioral responses. The concomitant changes in BDNF and corticosterone levels may mediate the changes in neural plasticity and synaptic functioning underlying clinical manifestations of PTSD.

Orexinergic Neurotransmission in Temperature Responses to Methamphetamine and Stress: Mathematical Modeling as a Data Assimilation Approach

PubMed Central

Behrouzvaziri, Abolhassan; Fu, Daniel; Tan, Patrick; Yoo, Yeonjoo; Zaretskaia, Maria V.; Rusyniak, Daniel E.; Molkov, Yaroslav I.; Zaretsky, Dmitry V.

2015-01-01

Experimental Data Orexinergic neurotransmission is involved in mediating temperature responses to methamphetamine (Meth). In experiments in rats, SB-334867 (SB), an antagonist of orexin receptors (OX1R), at a dose of 10 mg/kg decreases late temperature responses (t>60 min) to an intermediate dose of Meth (5 mg/kg). A higher dose of SB (30 mg/kg) attenuates temperature responses to low dose (1 mg/kg) of Meth and to stress. In contrast, it significantly exaggerates early responses (t<60 min) to intermediate and high doses (5 and 10 mg/kg) of Meth. As pretreatment with SB also inhibits temperature response to the stress of injection, traditional statistical analysis of temperature responses is difficult. Mathematical Modeling We have developed a mathematical model that explains the complexity of temperature responses to Meth as the interplay between excitatory and inhibitory nodes. We have extended the developed model to include the stress of manipulations and the effects of SB. Stress is synergistic with Meth on the action on excitatory node. Orexin receptors mediate an activation of on both excitatory and inhibitory nodes by low doses of Meth, but not on the node activated by high doses (HD). Exaggeration of early responses to high doses of Meth involves disinhibition: low dose of SB decreases tonic inhibition of HD and lowers the activation threshold, while the higher dose suppresses the inhibitory component. Using a modeling approach to data assimilation appears efficient in separating individual components of complex response with statistical analysis unachievable by traditional data processing methods. PMID:25993564

Plant Flavonoids—Biosynthesis, Transport and Involvement in Stress Responses

PubMed Central

Petrussa, Elisa; Braidot, Enrico; Zancani, Marco; Peresson, Carlo; Bertolini, Alberto; Patui, Sonia; Vianello, Angelo

2013-01-01

This paper aims at analysing the synthesis of flavonoids, their import and export in plant cell compartments, as well as their involvement in the response to stress, with particular reference to grapevine (Vitis vinifera L.). A multidrug and toxic compound extrusion (MATE) as well as ABC transporters have been demonstrated in the tonoplast of grape berry, where they perform a flavonoid transport. The involvement of a glutathione S-transferase (GST) gene has also been inferred. Recently, a putative flavonoid carrier, similar to mammalian bilitranslocase (BTL), has been identified in both grape berry skin and pulp. In skin the pattern of BTL expression increases from véraison to harvest, while in the pulp its expression reaches the maximum at the early ripening stage. Moreover, the presence of BTL in vascular bundles suggests its participation in long distance transport of flavonoids. In addition, the presence of a vesicular trafficking in plants responsible for flavonoid transport is discussed. Finally, the involvement of flavonoids in the response to stress is described. PMID:23867610

Minimizing cows' stress when calves were early weaned using the two-step method with nose flaps.

PubMed

Ungerfeld, R; Quintans, G; Hötzel, M J

2016-11-01

Early weaning may be used in beef cattle production to improve reproduction rates in range conditions. However, weaning causes a stress response in cows, which may be especially strong in early weaning management, as the bond between the cow and the calf is still strong. We hypothesized that weaning calves in two steps, with the aid of anti-sucking devices (nose flaps) would reduce the behavioural stress response in the cows separated from their calves 2 months after parturition. We compared the behaviour frequency and weight change in cows that were weaned abruptly, by separation of the calf on day 0 of the study, or in two steps, consisting of the use of anti-sucking nose flaps for 5 days before permanent separation; a third group was not weaned to serve as control. Thirty-six crossbred multiparous Aberdeen Angus×Hereford cows and their calves (n=12/treatment) were managed in three paddocks with similar pasture availability, with four dyads from each treatment per paddock. Cows' behaviour was observed by direct visual instantaneous sampling, at 10 min intervals from days -3 to 11. Weaning the calves in two steps clearly attenuated the behavioural stress response observed in abruptly weaned cows, which included reductions in grazing and lying, and increases in pacing, walking and vocalizing. Our results corroborate those previously shown for cows nursing older calves, and indicate that step weaning can reduce the behavioural stress response of cows at weaning, even when the calf is weaned shortly after birth, when the bond between the cow and calf is still very strong.

RESEARCH: Conceptualizing Environmental Stress: A Stress-Response Model of Coastal Sandy Barriers.

PubMed

Gabriel; Kreutzwiser

2000-01-01

/ The purpose of this paper is to develop and apply a conceptual framework of environmental stress-response for a geomorphic system. Constructs and methods generated from the literature were applied in the development of an integrative stress-response framework using existing environmental assessment techniques: interaction matrices and a systems diagram. Emphasis is on the interaction between environmental stress and the geomorphic environment of a sandy barrier system. The model illustrates a number of stress concepts pertinent to modeling environmental stress-response, including those related to stress-dependency, frequency-recovery relationships, environmental heterogeneity, spatial hierarchies and linkages, and temporal change. Sandy barrier stress-response and recovery are greatly impacted by fluctuating water levels, stress intensity and frequency, as well as environmental gradients such as differences in sediment storage and supply. Aspects of these stress-response variables are articulated in terms of three main challenges to management: dynamic stability, spatial integrity, and temporal variability. These in turn form the framework for evaluative principles that may be applied to assess how policies and management practices reflect key biophysical processes and human stresses identified by the model.

Evidence of an IFN-γ by early life stress interaction in the regulation of amygdala reactivity to emotional stimuli.

PubMed

Redlich, Ronny; Stacey, David; Opel, Nils; Grotegerd, Dominik; Dohm, Katharina; Kugel, Harald; Heindel, Walter; Arolt, Volker; Baune, Bernhard T; Dannlowski, Udo

2015-12-01

Since numerous studies have found that exposure to early life stress leads to increased peripheral inflammation and psychiatric disease, it is thought that peripheral immune activation precedes and possibly mediates the onset of stress-associated psychiatric disease. Despite early studies, IFNγ has received little attention relative to other inflammatory cytokines in the context of the pathophysiology of affective disorders. Neuroimaging endophenotypes have emerged recently as a promising means of elucidating these types of complex relationships including the modeling of the interaction between environmental factors and genetic predisposition. Here we investigate the GxE relationship between early-life stress and genetic variants of IFNγ on emotion processing. To investigate the impact of the relationship between genetic variants of IFNγ (rs1861494, rs2069718, rs2430561) and early life stress on emotion processing, a sample of healthy adults (n=409) undergoing an emotional faces paradigm in an fMRI study were genotyped and analysed. Information on early life stress was obtained via Childhood Trauma Questionnaire (CTQ). A positive association between early life stress and amygdala reactivity was found. Specifically, the main effect of genotype of rs1861494 on amygdala reactivity indicates a higher neural response in C allele carriers compared to T homozygotes, while we did not find main effects of rs2069718 and rs2430561. Importantly, interaction analyses revealed a specific interaction between IFNγ genotype (rs1861494) and early life stress affecting amygdala reactivity to emotional faces, resulting from a positive association between CTQ scores and amygdala reactivity in C allele carriers while this association was absent in T homozygotes. Our findings indicate that firstly the genetic variant of IFNγ (rs1861494) is involved with the regulation of amygdala reactivity to emotional stimuli and secondly, that this genetic variant moderates effects of early life

Lymphoproliferative and gamma interferon responses to stress-regulated Mycobacterium avium subsp. paratuberculosis recombinant proteins.

PubMed

Gurung, Ratna B; Begg, Douglas J; Purdie, Auriol C; de Silva, Kumudika; Bannantine, John P; Whittington, Richard J

2014-06-01

Johne's disease in ruminants is a chronic infection of the intestines caused by Mycobacterium avium subsp. paratuberculosis. An important strategy to control disease is early detection, and a potentially efficient method for early detection is measurement of cell-mediated immune responses developed by the host in response to exposure or infection. One method is to measure lymphoproliferation and cytokine release from the host cells when exposed to the organism or parts of the organism. In this study, 10 recombinant M. avium subsp. paratuberculosis proteins known to be upregulated under in vitro stress conditions were evaluated by examining their ability to evoke memory as a result of exposure by vaccination or oral challenge with live Mycobacterium avium subsp. paratuberculosis. Out of 10 proteins, MAP2698c was found to induce higher cell-mediated immune responses in vaccinated and challenged sheep in comparison to healthy controls. The findings suggest that not all stress-regulated proteins have the diagnostic potential to detect cell-mediated immune responses in ovine paratuberculosis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Lymphoproliferative and Gamma Interferon Responses to Stress-Regulated Mycobacterium avium subsp. paratuberculosis Recombinant Proteins

PubMed Central

Gurung, Ratna B.; Begg, Douglas J.; Purdie, Auriol C.; de Silva, Kumudika; Bannantine, John P.

2014-01-01

Johne's disease in ruminants is a chronic infection of the intestines caused by Mycobacterium avium subsp. paratuberculosis. An important strategy to control disease is early detection, and a potentially efficient method for early detection is measurement of cell-mediated immune responses developed by the host in response to exposure or infection. One method is to measure lymphoproliferation and cytokine release from the host cells when exposed to the organism or parts of the organism. In this study, 10 recombinant M. avium subsp. paratuberculosis proteins known to be upregulated under in vitro stress conditions were evaluated by examining their ability to evoke memory as a result of exposure by vaccination or oral challenge with live Mycobacterium avium subsp. paratuberculosis. Out of 10 proteins, MAP2698c was found to induce higher cell-mediated immune responses in vaccinated and challenged sheep in comparison to healthy controls. The findings suggest that not all stress-regulated proteins have the diagnostic potential to detect cell-mediated immune responses in ovine paratuberculosis. PMID:24695774

Early heart rate responses to standardized trauma-related pictures predict posttraumatic stress disorder – a prospective study

PubMed Central

Suendermann, Oliver; Ehlers, Anke; Boellinghaus, Inga; Gamer, Matthias; Glucksman, Edward

2010-01-01

BACKGROUND Trauma survivors with posttraumatic stress disorder (PTSD) report heightened physiological responses to a wide range of stimuli. It has been suggested that associative learning and stimulus generalization play a key role in the development of these symptoms. Some studies have found that trauma survivors with PTSD show greater physiological responses to individualized trauma reminders in the initial weeks after trauma than those without PTSD. This study investigated whether heart rate and skin conductance responses (HRR, SCR) to standardized trauma-related pictures at 1 month after the trauma predict chronic PTSD. METHOD Survivors of motor vehicle accidents or physical assaults (N=166) watched standardized trauma-related, generally threatening and neutral pictures at 1 month post- trauma while their HRR and SCR were recorded. PTSD symptoms were assessed with structured clinical interviews at 1 and 6 months; self-reports of fear responses and dissociation during trauma were obtained soon after the trauma. RESULTS At 1 month, trauma survivors with PTSD showed greater HRR to trauma-related pictures than those without PTSD, but not to general threat or neutral pictures. HRR to trauma-related pictures predicted PTSD severity at 1 and 6 months, and were related to fear and dissociation during trauma. SCR was not related to PTSD. CONCLUSION HRR to standardized trauma reminders at 1 month after the trauma differentiate between trauma survivors with and without PTSD, and predict chronic PTSD. Results are consistent with a role of associative learning in PTSD and suggest that early stimulus generalization may be an indicator of risk for chronic PTSD. PMID:20124426

PERIPHERAL IMMUNE SYSTEM SUPPRESSION IN EARLY ABSTINENT ALCOHOL DEPENDENT INDIVIDUALS: LINKS TO STRESS AND CUE-RELATED CRAVING

PubMed Central

Fox, Helen C; Milivojevic, Verica; Angarita, Gustavo A; Stowe, Raymond; Sinha, Rajita

2017-01-01

Background Peripheral immune system cytokines may play an integral role in underlying sensitized stress response and alcohol craving during early withdrawal. To date, the nature of these immune changes during early abstinence have not been examined. Methods Thirty-nine early abstinent, treatment-seeking alcohol dependent individuals and 46 socially drinking controls were exposed to three guided imageries: stress, alcohol cue and neutral. These were presented randomly across consecutive days. Plasma measures of tumor necrosis factor alpha (TNFα), tumor necrosis factor receptor 1 (TNFR1), interleukin-6 (IL-6), and interleukin-10 (IL-10), were collected at baseline, immediately after imagery and at various recovery time-points. Ratings of alcohol craving, negative mood and anxiety were also obtained at the same time-points. Results The alcohol group demonstrated decreased basal IL-10 compared with controls particularly following exposure to alcohol cue. They also showed a dampened TNFα and TNFR1 response to stress and cue, respectively, and a generalized suppression of IL-6. In the alcohol group, these immune system adaptations occurred alongside significant elevations in anxiety, negative mood and alcohol craving. Conclusions Findings demonstrate that broad immuno-suppression is still observed in alcohol dependent individuals after three weeks of abstinence and may be linked to motivation for alcohol. PMID:28675117

The influence of social support and perceived stress on response time inconsistency.

PubMed

Phibbs, Sandi; Stawski, Robert S; MacDonald, Stuart W S; Munoz, Elizabeth; Smyth, Joshua M; Sliwinski, Martin J

2017-11-24

Lack of social support and high levels of stress represent potentially modifiable risk factors for cognitive aging. In this study we examined the relationships between these two risk factors and response time inconsistency (RTI), or trial-to-trial variability in choice response time tasks. RTI is an early indicator of declining cognitive health, and examining the influence of modifiable psychosocial risk factors on RTI is important for understanding and promoting cognitive health during adulthood and old age. Using data from a community sample study (n = 317; M age = 49, range = 19-83), we examined the effects of social support, including size of network and satisfaction with support, global perceived stress, and their interactions on RTI. Neither size of network nor satisfaction with support was associated with RTI independent of perceived stress. Stress was positively associated with increased RTI on all tasks, independent of social support. Perceived stress did not interact with either dimension of social support to predict RTI, and perceived stress effects were invariant across age and sex. Perceived stress, but not social support, may be a unique and modifiable risk factor for normal and pathological cognitive aging. Discussion focuses on the importance of perceived stress and its impact on RTI in supporting cognitive health in adulthood and old age.

Impact of early life adversity on EMG stress reactivity of the trapezius muscle.

PubMed

Luijcks, Rosan; Vossen, Catherine J; Roggeveen, Suzanne; van Os, Jim; Hermens, Hermie J; Lousberg, Richel

2016-09-01

Human and animal research indicates that exposure to early life adversity increases stress sensitivity later in life. While behavioral markers of adversity-induced stress sensitivity have been suggested, physiological markers remain to be elucidated. It is known that trapezius muscle activity increases during stressful situations. The present study examined to what degree early life adverse events experienced during early childhood (0-11 years) and adolescence (12-17 years) moderate experimentally induced electromyographic (EMG) stress activity of the trapezius muscles, in an experimental setting. In a general population sample (n = 115), an anticipatory stress effect was generated by presenting a single unpredictable and uncontrollable electrical painful stimulus at t = 3 minutes. Subjects were unaware of the precise moment of stimulus delivery and its intensity level. Linear and nonlinear time courses in EMG activity were modeled using multilevel analysis. The study protocol included 2 experimental sessions (t = 0 and t = 6 months) allowing for examination of reliability.Results show that EMG stress reactivity during the stress paradigm was consistently stronger in people with higher levels of early life adverse events; early childhood adversity had a stronger moderating effect than adolescent adversity. The impact of early life adversity on EMG stress reactivity may represent a reliable facet that can be used in both clinical and nonclinical studies.

A Prospective Examination of Emotional Clarity, Stress Responses, and Depressive Symptoms during Early Adolescence

ERIC Educational Resources Information Center

Flynn, Megan; Rudolph, Karen D.

2014-01-01

This study examined the proposal that difficulty understanding one's emotional experiences (i.e., deficits in emotional clarity) would interfere with the formulation of adaptive responses to interpersonal stress, which would then predict depressive symptoms. This process was examined across 3 years (fourth to sixth grade) during early…

Modulation of the Hypothalamic-Pituitary-Adrenal Axis by Early Life Stress Exposure

PubMed Central

van Bodegom, Miranda; Homberg, Judith R.; Henckens, Marloes J. A. G.

2017-01-01

Exposure to stress during critical periods in development can have severe long-term consequences, increasing overall risk on psychopathology. One of the key stress response systems mediating these long-term effects of stress is the hypothalamic-pituitary-adrenal (HPA) axis; a cascade of central and peripheral events resulting in the release of corticosteroids from the adrenal glands. Activation of the HPA-axis affects brain functioning to ensure a proper behavioral response to the stressor, but stress-induced (mal)adaptation of the HPA-axis' functional maturation may provide a mechanistic basis for the altered stress susceptibility later in life. Development of the HPA-axis and the brain regions involved in its regulation starts prenatally and continues after birth, and is protected by several mechanisms preventing corticosteroid over-exposure to the maturing brain. Nevertheless, early life stress (ELS) exposure has been reported to have numerous consequences on HPA-axis function in adulthood, affecting both its basal and stress-induced activity. According to the match/mismatch theory, encountering ELS prepares an organism for similar (“matching”) adversities during adulthood, while a mismatching environment results in an increased susceptibility to psychopathology, indicating that ELS can exert either beneficial or disadvantageous effects depending on the environmental context. Here, we review studies investigating the mechanistic underpinnings of the ELS-induced alterations in the structural and functional development of the HPA-axis and its key external regulators (amygdala, hippocampus, and prefrontal cortex). The effects of ELS appear highly dependent on the developmental time window affected, the sex of the offspring, and the developmental stage at which effects are assessed. Albeit by distinct mechanisms, ELS induced by prenatal stressors, maternal separation, or the limited nesting model inducing fragmented maternal care, typically results in HPA

Seaweed extract improve drought tolerance of soybean by regulating stress-response genes.

PubMed

Shukla, Pushp S; Shotton, Katy; Norman, Erin; Neily, Will; Critchley, Alan T; Prithiviraj, Balakrishnan

2018-02-01

There is an increasing global concern about the availability of water for agricultural use. Drought stress negatively impacts plant physiology and crop productivity. Soybean ( Glycine max ) is one of the important oilseed crops, and its productivity is often reduced by drought. In this study, a commercial extract of Ascophyllum nodosum (ANE) was evaluated for its potential to alleviate drought stress in soybean. The aim of this study was to determine the effects of ANE on the response of soybean plants to drought stress by monitoring stomatal conductance, relative leaf water content, antioxidant activity and expression of stress-responsive genes. Plants treated with ANE had higher relative water content and higher stomatal conductance under drought stress. During early recovery in the post-drought phase, ANE treated plants had significantly higher stomatal conductance. The antioxidant activity was also found higher in the plants treated with ANE. In addition, ANE-treatment led to changes in the expression of stress-responsive genes: GmCYP707A1a , GmCYP707A3b , GmRD22 , GmRD20 , GmDREB1B , GmERD1 , GmNFYA3 , FIB1a , GmPIP1b , GmGST , GmBIP and GmTp55 . Taken together, these results suggest that applications of ANE improve the drought tolerance of soybean by changing physiology and gene expression.

Seaweed extract improve drought tolerance of soybean by regulating stress-response genes

PubMed Central

Shukla, Pushp S; Shotton, Katy; Norman, Erin; Neily, Will; Critchley, Alan T

2018-01-01

Abstract There is an increasing global concern about the availability of water for agricultural use. Drought stress negatively impacts plant physiology and crop productivity. Soybean (Glycine max) is one of the important oilseed crops, and its productivity is often reduced by drought. In this study, a commercial extract of Ascophyllum nodosum (ANE) was evaluated for its potential to alleviate drought stress in soybean. The aim of this study was to determine the effects of ANE on the response of soybean plants to drought stress by monitoring stomatal conductance, relative leaf water content, antioxidant activity and expression of stress-responsive genes. Plants treated with ANE had higher relative water content and higher stomatal conductance under drought stress. During early recovery in the post-drought phase, ANE treated plants had significantly higher stomatal conductance. The antioxidant activity was also found higher in the plants treated with ANE. In addition, ANE-treatment led to changes in the expression of stress-responsive genes: GmCYP707A1a, GmCYP707A3b, GmRD22, GmRD20, GmDREB1B, GmERD1, GmNFYA3, FIB1a, GmPIP1b, GmGST, GmBIP and GmTp55. Taken together, these results suggest that applications of ANE improve the drought tolerance of soybean by changing physiology and gene expression. PMID:29308122

Adiposity moderates links from early adversity and depressive symptoms to inflammatory reactivity to acute stress during late adolescence.

PubMed

Chiang, Jessica J; Bower, Julienne E; Irwin, Michael R; Taylor, Shelley E; Fuligni, Andrew J

2017-11-01

Both early adversity and depression are associated with heightened inflammation. However, few studies have focused on inflammatory reactivity to psychosocial stress and examined adiposity as a potential moderator. Yet, repeated heightened inflammatory reactivity over time is thought to contribute to low-grade chronic inflammation and adipose tissue is a key source of pro-inflammatory cytokines. The purpose of the present study was to examine whether early adversity and depressive symptoms were related to stress-induced inflammation and whether these associations varied by total body and abdominal adiposity as measured by body mass index (BMI) and waist circumference (WC) in a sample of late adolescents. Participants reported on their early family environment and current depressive symptoms, had their height, weight, and WC assessed for adiposity markers, and provided blood samples for IL-6 assessment before and after a standardized laboratory stress task. No main effect of early adversity on IL-6 reactivity to acute stress was observed. However, significant interactions between early adversity and BMI and WC emerged. Greater exposure to early adversity was associated with greater IL-6 responses only among adolescents with higher BMI or WC. The same pattern of findings was observed for depressive symptoms. Additionally, moderated mediation analyses indicated that among adolescents with greater adiposity, early adversity indirectly influenced IL-6 reactivity via current depressive symptoms. These findings contribute to our understanding of vulnerability factors that may amplify the associations between early adversity and depressive symptoms and inflammation during relatively early stages of life. Copyright © 2017 Elsevier Inc. All rights reserved.

Tornado disasters and stress responses.

PubMed

Godleski, L S

1997-04-01

Each year, a number of tornados rip through Kentucky, leaving fear, destruction, and human injury in their path. Persons who endure these catastrophes often experience a variety of stress responses. The psychological and medical sequelae include depression, acute and post-traumatic stress disorders, substance abuse, anxiety, and somatization. It is especially important for the Kentucky practitioner to be able to recognize and screen for pathology following a tornado disaster in order to provide leadership in ascertaining treatment for such stress responses.

STRESS RESPONSE STUDIES USING ANIMAL MODELS

EPA Science Inventory

This presentation will provide the evidence that ozone exposure in animal models induce neuroendocrine stress response and this stress response modulates lung injury and inflammation through adrenergic and glucocorticoid receptors.

Anger responses to psychosocial stress predict heart rate and cortisol stress responses in men but not women.

PubMed

Lupis, Sarah B; Lerman, Michelle; Wolf, Jutta M

2014-11-01

While previous research has suggested that anger and fear responses to stress are linked to distinct sympathetic nervous system (SNS) stress responses, little is known about how these emotions predict hypothalamus-pituitary-adrenal (HPA) axis reactivity. Further, earlier research primarily relied on retrospective self-report of emotion. The current study aimed at addressing both issues in male and female individuals by assessing the role of anger and fear in predicting heart rate and cortisol stress responses using both self-report and facial coding analysis to assess emotion responses. We exposed 32 healthy students (18 female; 19.6±1.7 yr) to an acute psychosocial stress paradigm (TSST) and measured heart rate and salivary cortisol levels throughout the protocol. Anger and fear before and after stress exposure was assessed by self-report, and video recordings of the TSST were assessed by a certified facial coder to determine emotion expression (FACS). Self-reported emotions and emotion expressions did not correlate (all p>.23). Increases in self-reported fear predicted blunted cortisol responses in men (β=0.41, p=.04). Also for men, longer durations of anger expression predicted exaggerated cortisol responses (β=0.67 p=.004), and more anger incidences predicted exaggerated cortisol and heart rate responses (β=0.51, p=.033; β=0.46, p=.066, resp.). Anger and fear did not predict SNS or HPA activity for females (all p>.23). The current differential self-report and facial coding findings support the use of multiple modes of emotion assessment. Particularly, FACS but not self-report revealed a robust anger-stress association that could have important downstream health effects for men. For women, future research may clarify the role of other emotions, such as self-conscious expressions of shame, for physiological stress responses. A better understanding of the emotion-stress link may contribute to behavioral interventions targeting health-promoting ways of

Anger responses to psychosocial stress predict heart rate and cortisol stress responses in men but not women

PubMed Central

Lupis, Sarah B.; Lerman, Michelle; Wolf, Jutta M.

2014-01-01

While previous research has suggested that anger and fear responses to stress are linked to distinct sympathetic nervous system (SNS) stress responses, little is known about how these emotions predict hypothalamus-pituitary-adrenal (HPA) axis reactivity. Further, earlier research primarily relied on retrospective self-report of emotion. The current study aimed at addressing both issues in male and female individuals by assessing the role of anger and fear in predicting heart rate and cortisol stress responses using both self-report and facial coding analysis to assess emotion responses. We exposed 32 healthy students (18 female; 19.6+/−1.7 yrs.) to an acute psychosocial stress paradigm (TSST) and measured heart rate and salivary cortisol levels throughout the protocol. Anger and fear before and after stress exposure was assessed by self-report, and video recordings of the TSST were assessed by a certified facial coder to determine emotion expression (FACS). Self-reported emotions and emotion expressions did not correlate (all p > .23). Increases in self-reported fear predicted blunted cortisol responses in men (β = 0.41, p = .04). Also for men, longer durations of anger expression predicted exaggerated cortisol responses (β = 0.67 p = .004), and more anger incidences predicted exaggerated cortisol and heart rate responses (β = 0.51, p = .033; β = 0.46, p = .066, resp.). Anger and fear did not predict SNS or HPA activity for females (all p > .23). The current differential self-report and facial coding findings support the use of multiple modes of emotion assessment. Particularly, FACS but not self-report revealed a robust anger-stress association that could have important downstream health effects for men. For women, future research may clarify the role of other emotions, such as self-conscious expressions of shame, for physiological stress responses. A better understanding of the emotion-stress link may contribute to behavioral interventions targeting health

Early-life adversity programs emotional functions and the neuroendocrine stress system: the contribution of nutrition, metabolic hormones and epigenetic mechanisms.

PubMed

Yam, Kit-Yi; Naninck, Eva F G; Schmidt, Mathias V; Lucassen, Paul J; Korosi, Aniko

2015-01-01

Clinical and pre-clinical studies have shown that early-life adversities, such as abuse or neglect, can increase the vulnerability to develop psychopathologies and cognitive decline later in life. Remarkably, the lasting consequences of stress during this sensitive period on the hypothalamic-pituitary-adrenal axis and emotional function closely resemble the long-term effects of early malnutrition and suggest a possible common pathway mediating these effects. During early-life, brain development is affected by both exogenous factors, like nutrition and maternal care as well as by endogenous modulators including stress hormones. These elements, while mostly considered for their independent actions, clearly do not act alone but rather in a synergistic manner. In order to better understand how the programming by early-life stress takes place, it is important to gain further insight into the exact interplay of these key elements, the possible common pathways as well as the underlying molecular mechanisms that mediate their effects. We here review evidence that exposure to both early-life stress and early-life under-/malnutrition similarly lead to life-long alterations on the neuroendocrine stress system and modify emotional functions. We further discuss how the different key elements of the early-life environment interact and affect one another and next suggest a possible role for the early-life adversity induced alterations in metabolic hormones and nutrient availability in shaping later stress responses and emotional function throughout life, possibly via epigenetic mechanisms. Such knowledge will help to develop intervention strategies, which gives the advantage of viewing the synergistic action of a more complete set of changes induced by early-life adversity.

Youth Depression and Early Childrearing: Stress Generation and Intergenerational Transmission of Depression

ERIC Educational Resources Information Center

Hammen, Constance; Brennan, Patricia A.; Le Brocque, Robyne

2011-01-01

Objective: Broadening the concept of stress generation beyond acute life events, the current study explores predictors of the creation of stressful environments--specifically, selection into early childrearing by age 20. It was predicted that youth with early onset depressive disorders would be at higher risk for early childrearing accompanied by…

Responses to Fiscal Stress in Higher Education.

ERIC Educational Resources Information Center

Wilson, Robert A., Ed.

Proceedings of the 1981 University of Arizona conference on responses to fiscal stress in higher education are presented. Topics include the impact of the federal government on higher education, state and institutional responses to new federal policies, developing responses to fiscal stress, alternate perspectives on fiscal stress, and tactical…

Stress and resource pathways connecting early socioeconomic adversity to young adults' physical health risk.

PubMed

Wickrama, Kandauda K A S; Lee, Tae Kyoung; O'Neal, Catherine Walker; Kwon, Josephine A

2015-05-01

Although research has established the impact of early stress, including stressful life contexts, and early resources, such as educational attainment, on various adolescent health outcomes, previous research has not adequately investigated "integrative models" incorporating both stress and resource mediational pathways to explain how early socioeconomic adversity impacts physical health outcomes, particularly in early life stages. Data on early childhood/adolescent stress and socioeconomic resources as well as biomarkers indicating physical health status in young adulthood were collected from 11,798 respondents (54 % female) over a 13-year period from youth participating in the National Study of Adolescent Health (Add Health). Physical health risk in young adulthood was measured using a composite index of nine regulatory biomarkers of cardiovascular and metabolic systems. Heterogeneity in stress and socioeconomic resource pathways was assessed using latent class analysis to identify clusters, or classes, of stress and socioeconomic resource trajectories. The influence of early socioeconomic adversity on young adults' physical health risk, as measured by biomarkers, was estimated, and the role of stress and socioeconomic resource trajectory classes as linking mechanisms was assessed. There was evidence for the influence of early socioeconomic adversity on young adults' physical health risk directly and indirectly through stress and socioeconomic resource trajectory classes over the early life course. These findings suggest that health models should be broadened to incorporate both stress and resource experiences simultaneously. Furthermore, these findings have prevention and intervention implications, including the importance of early socioeconomic adversity and key intervention points for "turning" the trajectories of at-risk youth.

Impact of early life adversity on EMG stress reactivity of the trapezius muscle

PubMed Central

Luijcks, Rosan; Vossen, Catherine J.; Roggeveen, Suzanne; van Os, Jim; Hermens, Hermie J.; Lousberg, Richel

2016-01-01

Abstract Human and animal research indicates that exposure to early life adversity increases stress sensitivity later in life. While behavioral markers of adversity-induced stress sensitivity have been suggested, physiological markers remain to be elucidated. It is known that trapezius muscle activity increases during stressful situations. The present study examined to what degree early life adverse events experienced during early childhood (0–11 years) and adolescence (12–17 years) moderate experimentally induced electromyographic (EMG) stress activity of the trapezius muscles, in an experimental setting. In a general population sample (n = 115), an anticipatory stress effect was generated by presenting a single unpredictable and uncontrollable electrical painful stimulus at t = 3 minutes. Subjects were unaware of the precise moment of stimulus delivery and its intensity level. Linear and nonlinear time courses in EMG activity were modeled using multilevel analysis. The study protocol included 2 experimental sessions (t = 0 and t = 6 months) allowing for examination of reliability. Results show that EMG stress reactivity during the stress paradigm was consistently stronger in people with higher levels of early life adverse events; early childhood adversity had a stronger moderating effect than adolescent adversity. The impact of early life adversity on EMG stress reactivity may represent a reliable facet that can be used in both clinical and nonclinical studies. PMID:27684800

The effect of early to mid-gestational nutrient restriction on female offspring fertility and hypothalamic-pituitary-adrenal axis response to stress.

PubMed

Long, N M; Nijland, M J; Nathanielsz, P W; Ford, S P

2010-06-01

Primiparous ewes born as singletons to Rambouillet x Columbia crossbred ewes fed either 100% of NRC recommendations (control, Con; n = 7) or 50% of NRC (nutrient restricted, NR; n = 7) from d 28 through 78 postmating were utilized for this study. At 1 yr of age, a subset of ewes born to Con (n = 4) and NR (n = 4) mothers received jugular catheters and were subjected to a corticotrophin-releasing hormone (CRH)/arginine vasopressin (AVP) challenge, an ACTH challenge, and an isolation stress test, in which ACTH and cortisol responses were determined. A week after these challenges, estrus was monitored twice daily in all ewes from Con (n = 7) and NR mothers (n = 7). Once estrus was observed (d 0), daily blood samples were collected from ewes for progesterone through the subsequent estrus. Estrous detection and daily blood sampling were repeated during an estrous cycle in the next year, ewes were hand mated at the second estrus, and pregnancy was determined by delivery of a live lamb(s). Ewes from NR mothers tended (P = 0.10) to have a greater peak ACTH response after an intravenous CRH/AVP injection than ewes from Con mothers. The cortisol response of ewes to a CRH/AVP or ACTH challenge was not influenced by maternal nutrition. In contrast, ewes from Con mothers tended (P = 0.10) to release more ACTH in response to the isolation stress test and showed a greater (P = 0.04) cortisol release than ewes from NR mothers. Ewes from NR mothers exhibited decreased (P < 0.05) plasma progesterone in both yr 1 and 2 of the study compared with ewes from Con mothers. Furthermore, fewer (P < 0.0001) ewes from NR mothers produced a lamb (1 of 7) than ewes from Con mothers (7 of 7) during yr 2 of the study. These findings indicate that maternal undernutrition during early gestation may affect stress responses by the offspring, but has limited impact on hypothalamo-pituitary-adrenal sensitivity. Furthermore, offspring of NR ewes exhibited reduced progesterone secretion during the luteal

Sex Differences in Stress Response Circuitry Activation Dependent on Female Hormonal Cycle

PubMed Central

Goldstein, Jill M.; Jerram, Matthew; Abbs, Brandon; Whitfield-Gabrieli, Susan; Makris, Nikos

2010-01-01

Understanding sex differences in stress regulation has important implications for understanding basic physiological differences in the male and female brain and their impact on vulnerability to sex differences in chronic medical disorders associated with stress response circuitry. In this fMRI study, we demonstrated that significant sex differences in brain activity in stress response circuitry were dependent on women's menstrual cycle phase. Twelve healthy Caucasian premenopausal women were compared to a group of healthy men from the same population, based on age, ethnicity, education, and right-handedness. Subjects were scanned using negative valence/high arousal versus neutral visual stimuli that we demonstrated activated stress response circuitry (amygdala, hypothalamus, hippocampus, brainstem, orbitofrontal and medial prefrontal cortices (OFC and mPFC), and anterior cingulate gyrus (ACG). Women were scanned twice based on normal variation in menstrual cycle hormones (i.e., early follicular (EF) compared with late follicular-midcycle menstrual phases (LF/MC)). Using SPM8b, there were few significant differences in BOLD signal changes in men compared to EF women, except ventromedial (VMN) and lateral (LHA) hypothalamus, left amygdala, and ACG. In contrast, men exhibited significantly greater BOLD signal changes compared to LF/MC women on bilateral ACG and OFC, mPFC, LHA, VMN, hippocampus, and periaqueductal gray, with largest effect sizes in mPFC and OFC. Findings suggest that sex differences in stress response circuitry are hormonally regulated via the impact of subcortical brain activity on the cortical control of arousal, and demonstrate that females have been endowed with a natural hormonal capacity to regulate the stress response that differs from males. PMID:20071507

Sex differences in stress response circuitry activation dependent on female hormonal cycle.

PubMed

Goldstein, Jill M; Jerram, Matthew; Abbs, Brandon; Whitfield-Gabrieli, Susan; Makris, Nikos

2010-01-13

Understanding sex differences in stress regulation has important implications for understanding basic physiological differences in the male and female brain and their impact on vulnerability to sex differences in chronic medical disorders associated with stress response circuitry. In this functional magnetic resonance imaging study, we demonstrated that significant sex differences in brain activity in stress response circuitry were dependent on women's menstrual cycle phase. Twelve healthy Caucasian premenopausal women were compared to a group of healthy men from the same population, based on age, ethnicity, education, and right handedness. Subjects were scanned using negative valence/high arousal versus neutral visual stimuli that we demonstrated activated stress response circuitry [amygdala, hypothalamus, hippocampus, brainstem, orbitofrontal cortex (OFC), medial prefrontal cortex (mPFC), and anterior cingulate gyrus (ACG)]. Women were scanned twice based on normal variation in menstrual cycle hormones [i.e., early follicular (EF) compared with late follicular-midcycle (LF/MC) menstrual phases]. Using SPM8b, there were few significant differences in blood oxygenation level-dependent (BOLD) signal changes in men compared to EF women, except ventromedial nucleus (VMN), lateral hypothalamic area (LHA), left amygdala, and ACG. In contrast, men exhibited significantly greater BOLD signal changes compared to LF/MC women on bilateral ACG and OFC, mPFC, LHA, VMN, hippocampus, and periaqueductal gray, with largest effect sizes in mPFC and OFC. Findings suggest that sex differences in stress response circuitry are hormonally regulated via the impact of subcortical brain activity on the cortical control of arousal, and demonstrate that females have been endowed with a natural hormonal capacity to regulate the stress response that differs from males.

Peritraumatic dissociation, acute stress, and early posttraumatic stress disorder in victims of general crime.

PubMed

Birmes, P; Carreras, D; Ducassé, J L; Charlet, J P; Warner, B A; Lauque, D; Schmitt, L

2001-09-01

To compare the relation between peritraumatic dissociation and acute stress and the early development of posttraumatic stress disorder (PTSD) in victims of general crime. A total of 48 subjects were assessed within 24 hours of the trauma, using the Peritraumatic Dissociative Experiences Questionnaire Self-Report Version (PDEQ-SRV). They were followed longitudinally to assess acute stress (2 weeks after the assault,) using the Standford Acute Stress Reaction Questionnaire (SASRQ), and posttraumatic stress (at 5 weeks), using the Clinician-Administered PTSD Scale (CAPS) and the Impact of Event Scale (IES). Among PTSD subjects mean PDEQ scores were significantly higher (mean 3, SD 0.9) than in those without PTSD (mean 2.3, SD 0.7) (t = 2.78, df 46, P = 0.007). Among PTSD subjects, mean SASRQ scores were significantly higher (mean 97.9, SD 29.2) than in those without PTSD (mean 54.8, SD 28.2) (t = 4.9, df 46, P = 0.00007). High levels of peritraumatic dissociation and acute stress following violent assault are risk factors for early PTSD. Identifying acute reexperiencing can help the clinician identify subjects at highest risk.

Quantitative Proteomic Profiling of Early and Late Responses to Salicylic Acid in Cucumber Leaves

PubMed Central

Li, Liang; Shang, Qing-Mao

2016-01-01

Salicylic acid (SA) is an important phytohormone that plays vital regulatory roles in plant growth, development, and stress responses. However, studies on the molecular mechanism of SA, especially during the early SA responses, are lagging behind. In this study, we initiated a comprehensive isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomic analysis to explore the early and late SA-responsive proteins in leaves of cucumber (Cucumis sativus L.) seedlings. Upon SA application through the roots, endogenous SA accumulated in cucumber leaves. By assaying the changes in marker gene expression and photosynthetic rate, we collected samples at 12 h and 72 h post treatment (hpt) to profile the early and late SA responsiveness, respectively. The iTRAQ assay followed by tandem mass spectrometry revealed 135 differentially expressed proteins (DEPs) at 12 hpt and 301 DEPs at 72 hpt. The functional categories for these SA-responsive proteins included in a variety of biochemical processes, including photosynthesis, redox homeostasis, carbohydrate and energy metabolism, lipid metabolism, transport, protein folding and modification, proteolysis, cell wall organization, and the secondary phenylpropanoid pathway. Conclusively, based on the abundant changes of these DEPs, together with their putative functions, we proposed a possible SA-responsive protein network. It appears that SA could elicit reactive oxygen species (ROS) production via enhancing the photosynthetic electron transferring, and then confer some growth-promoting and stress-priming effects on cells during the late phase, including enhanced photosynthesis and ROS scavenging, altered carbon metabolic flux for the biosynthesis of amino acids and nucleotides, and cell wall reorganization. Overall, the present iTRAQ assay provides higher proteome coverage and deepened our understanding of the molecular basis of SA-responses. PMID:27551830

RNA-seq analysis of early hepatic response to handling and confinement stress in rainbow trout

USDA-ARS?s Scientific Manuscript database

Fish under intensive rearing conditions experience various stressors which have negative impacts on survival, growth and fillet quality. Identifying and characterizing the molecular mechanisms underlying stress responses will facilitate the development of strategies that aim to improve animal welfar...

Plant responses to water stress

PubMed Central

Kar, Rup Kumar

2011-01-01

Terrestrial plants most often encounter drought stress because of erratic rainfall which has become compounded due to present climatic changes.Responses of plants to water stress may be assigned as either injurious change or tolerance index. One of the primary and cardinal changes in response to drought stress is the generation of reactive oxygen species (ROS), which is being considered as the cause of cellular damage. However, recently a signaling role of such ROS in triggering the ROS scavenging system that may confer protection or tolerance against stress is emerging. Such scavenging system consists of antioxidant enzymes like SOD, catalase and peroxidases, and antioxidant compounds like ascorbate, reduced glutathione; a balance between ROS generation and scavenging ultimately determines the oxidative load. As revealed in case of defence against pathogen, signaling via ROS is initiated by NADPH oxidase-catalyzed superoxide generation in the apoplastic space (cell wall) followed by conversion to hydrogen peroxide by the activity of cell wall-localized SOD. Wall peroxidase may also play role in ROS generation for signaling. Hydrogen peroxide may use Ca2+ and MAPK pathway as downstream signaling cascade. Plant hormones associated with stress responses like ABA and ethylene play their role possibly via a cross talk with ROS towards stress tolerance, thus projecting a dual role of ROS under drought stress. PMID:22057331

Early-life stress origins of gastrointestinal disease: animal models, intestinal pathophysiology, and translational implications

PubMed Central

Pohl, Calvin S.; Medland, Julia E.

2015-01-01

Early-life stress and adversity are major risk factors in the onset and severity of gastrointestinal (GI) disease in humans later in life. The mechanisms by which early-life stress leads to increased GI disease susceptibility in adult life remain poorly understood. Animal models of early-life stress have provided a foundation from which to gain a more fundamental understanding of this important GI disease paradigm. This review focuses on animal models of early-life stress-induced GI disease, with a specific emphasis on translational aspects of each model to specific human GI disease states. Early postnatal development of major GI systems and the consequences of stress on their development are discussed in detail. Relevant translational differences between species and models are highlighted. PMID:26451004

Epidural analgesia in early labour blocks the stress response but uterine contractions remain unchanged.

PubMed

Scull, T J; Hemmings, G T; Carli, F; Weeks, S K; Mazza, L; Zingg, H H

1998-07-01

To determine the effect of epidural analgesia on biochemical markers of stress, plasma oxytocin concentrations and frequency of uterine contractions during the first stage of labour. Nine nulliparous women, in spontaneous labour, with a singleton fetus and cervical dilatation < or = 5 cm were enrolled. Epidural bupivacaine 0.25% (range 10-14 ml) was administered and bilateral sensory blockade to ice (T8-L4) achieved. Blood samples were collected before the epidermal block and every 10 min for one hour after the block was achieved for the measurement of plasma beta-endorphin, cortical, glucose, lactate and oxytocin concentrations. No exogenous oxytocin was given. Intensity of pain was assessed at the time of the blood sampling using a 10 cm visual analogue scale (VAS). The frequency of uterine contractions was recorded for 60 min before and after the epidural block. There was a decrease in plasma beta-endorphin and cortisol concentrations after epidural block (P < 0.01). There were no changes in plasma glucose and lactate concentrations. The mean VAS for pain decreased 10 min after epidural block was achieved and remained < 2 throughout the study period (P < 0.001). Mean plasma oxytocin concentrations did not change. The frequency of uterine contractions before and after the epidural block was similar. The metabolic stress response to the pain of labour was attenuated by epidural analgesia. In contrast, plasma oxytocin concentration and frequency of uterine contractions were unaffected by the attenuation of metabolic stress response.

Behavioural response to combined insecticide and temperature stress in natural populations of Drosophila melanogaster.

PubMed

Fournier-Level, A; Neumann-Mondlak, A; Good, R T; Green, L M; Schmidt, J M; Robin, C

2016-05-01

Insecticide resistance evolves extremely rapidly, providing an illuminating model for the study of adaptation. With climate change reshaping species distribution, pest and disease vector control needs rethinking to include the effects of environmental variation and insect stress physiology. Here, we assessed how both long-term adaptation of populations to temperature and immediate temperature variation affect the genetic architecture of DDT insecticide response in Drosophila melanogaster. Mortality assays and behavioural assays based on continuous activity monitoring were used to assess the interaction between DDT and temperature on three field-derived populations from climate extremes (Raleigh for warm temperate, Tasmania for cold oceanic and Queensland for hot tropical). The Raleigh population showed the highest mortality to DDT, whereas the Queensland population, epicentre for derived alleles of the resistance gene Cyp6g1, showed the lowest. Interaction between insecticide and temperature strongly affected mortality, particularly for the Tasmanian population. Activity profiles analysed using self-organizing maps show that the insecticide promoted an early response, whereas elevated temperature promoted a later response. These distinctive early or later activity phases revealed similar responses to temperature and DDT dose alone but with more or less genetic variance depending on the population. This change in genetic variance among populations suggests that selection particularly depleted genetic variance for DDT response in the Queensland population. Finally, despite similar (co)variation between traits in benign conditions, the genetic responses across population differed under stressful conditions. This showed how stress-responsive genetic variation only reveals itself in specific conditions and thereby escapes potential trade-offs in benign environments. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European

Little Kids, Big Worries: Stress-Busting Tips for Early Childhood Classrooms

ERIC Educational Resources Information Center

Honig, Alice Sterling

2010-01-01

Research shows that stress in the crucial early years of a child's life can pose dramatic, lasting challenges to development, learning, and behavior. This is the practical book early childhood professionals need to recognize stress in young children--and intervene with proven relief strategies before pressures turn into big problems. Developed by…

Obesity induced alterations in redox homeostasis and oxidative stress are present from an early age.

PubMed

Lechuga-Sancho, Alfonso M; Gallego-Andujar, David; Ruiz-Ocaña, Pablo; Visiedo, Francisco M; Saez-Benito, Ana; Schwarz, Mónica; Segundo, Carmen; Mateos, Rosa M

2018-01-01

Oxidative stress and inflammation have been postulated as underlying mechanisms for the development of obesity-related insulin resistance. This association however, remains elusive especially in childhood. We sought to investigate this relation by measuring oxidative stress and antioxidant response biomarkers, before and during an oral glucose tolerance test (OGTT), in different biological samples from obese children. 24 children were recruited for the study, (18 obese and 6 controls). After OGTT, the obese group was subdivided in two, according to whether or not carbohydrate metabolic impairment (Ob.IR+, Ob.IR-; respectively) was found. Different biomarkers were analyzed after fasting (T = 0) and during an OGTT (T = 60 and 120 min). Lipoperoxides were measured in plasma, erythrocytes, and urine; while advanced glycation end products were determined in plasma, and redox status (GSH/GSSG ratio) in erythrocytes. We found marked differences in the characterization of the oxidative status in urine and erythrocytes, and in the dynamics of the antioxidant response during OGTT. Specifically, Ob.IR+ children show increased oxidative stress, deficient antioxidant response and a significant imbalance in redox status, in comparison to controls and Ob.IR- children. Obese children with insulin resistance show increased levels of oxidative stress biomarkers, and a stunted antioxidant response to an OGTT leading to increased oxidative stress after a single glucose load, as detected in erythrocytes, but not in plasma. We propose erythrocytes as sensors of early and acute changes in oxidative stress associated with insulin resistance in childhood obesity. This is a pilot study, performed with a limited sample size, so data should be interpreted with caution until reproduced.

Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part I: responses in the roots.

PubMed

Vanhoudt, Nathalie; Vandenhove, Hildegarde; Horemans, Nele; Remans, Tony; Opdenakker, Kelly; Smeets, Karen; Bello, Daniel Martinez; Wannijn, Jean; Van Hees, May; Vangronsveld, Jaco; Cuypers, Ann

2011-06-01

When aiming to evaluate the environmental impact of uranium contamination, it is important to unravel the mechanisms by which plants respond to uranium stress. As oxidative stress seems an important modulator under other heavy metal stress, this study aimed to investigate oxidative stress related responses in Arabidopsis thaliana exposed to uranium concentrations ranging from 0.1 to 100 μM for 1, 3 and 7 days. Besides analyzing relevant reactive oxygen species-producing and -scavenging enzymes at protein and transcriptional level, the importance of the ascorbate-glutathione cycle under uranium stress was investigated. These results are reported separately for roots and leaves in two papers: Part I dealing with responses in the roots and Part II unraveling responses in the leaves and presenting general conclusions. Results of Part I indicate that oxidative stress related responses in the roots were only triggered following exposure to the highest uranium concentration of 100 μM. A fast oxidative burst was suggested based on the observed enhancement of lipoxygenase (LOX1) and respiratory burst oxydase homolog (RBOHD) transcript levels already after 1 day. The first line of defense was attributed to superoxide dismutase (SOD), also triggered from the first day. The enhanced SOD-capacity observed at protein level corresponded with an enhanced expression of iron SOD (FSD1) located in the plastids. For the detoxification of H(2)O(2), an early increase in catalase (CAT1) transcript levels was observed while peroxidase capacities were enhanced at the later stage of 3 days. Although the ascorbate peroxidase capacity and gene expression (APX1) increased, the ascorbate/dehydroascorbate redox balance was completely disrupted and shifted toward the oxidized form. This disrupted balance could not be inverted by the glutathione part of the cycle although the glutathione redox balance could be maintained. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Yeast Environmental Stress Response Regulates Mutagenesis Induced by Proteotoxic Stress

PubMed Central

Shor, Erika; Fox, Catherine A.; Broach, James R.

2013-01-01

Conditions of chronic stress are associated with genetic instability in many organisms, but the roles of stress responses in mutagenesis have so far been elucidated only in bacteria. Here, we present data demonstrating that the environmental stress response (ESR) in yeast functions in mutagenesis induced by proteotoxic stress. We show that the drug canavanine causes proteotoxic stress, activates the ESR, and induces mutagenesis at several loci in an ESR-dependent manner. Canavanine-induced mutagenesis also involves translesion DNA polymerases Rev1 and Polζ and non-homologous end joining factor Ku. Furthermore, under conditions of chronic sub-lethal canavanine stress, deletions of Rev1, Polζ, and Ku-encoding genes exhibit genetic interactions with ESR mutants indicative of ESR regulating these mutagenic DNA repair processes. Analyses of mutagenesis induced by several different stresses showed that the ESR specifically modulates mutagenesis induced by proteotoxic stress. Together, these results document the first known example of an involvement of a eukaryotic stress response pathway in mutagenesis and have important implications for mechanisms of evolution, carcinogenesis, and emergence of drug-resistant pathogens and chemotherapy-resistant tumors. PMID:23935537

Coping and Responses to Stress in Navajo Adolescents: Psychometric Properties of the Responses to Stress Questionnaire

ERIC Educational Resources Information Center

Wadsworth, Martha E.; Rieckmann, Traci; Benson, Molly A.; Compas, Bruce E.

2004-01-01

This study tested the factor structure of coping and stress responses in Navajo adolescents and examined the reliability and validity of the Responses to Stress Questionnaire (RSQ; Connor-Smith, Compas, Wadsworth, Thomsen, & Saltzman, 2000) with this population. Confirmatory factor analyses revealed that a correlated five-factor model of…

Response to Hyperosmotic Stress

PubMed Central

Saito, Haruo; Posas, Francesc

2012-01-01

An appropriate response and adaptation to hyperosmolarity, i.e., an external osmolarity that is higher than the physiological range, can be a matter of life or death for all cells. It is especially important for free-living organisms such as the yeast Saccharomyces cerevisiae. When exposed to hyperosmotic stress, the yeast initiates a complex adaptive program that includes temporary arrest of cell-cycle progression, adjustment of transcription and translation patterns, and the synthesis and retention of the compatible osmolyte glycerol. These adaptive responses are mostly governed by the high osmolarity glycerol (HOG) pathway, which is composed of membrane-associated osmosensors, an intracellular signaling pathway whose core is the Hog1 MAP kinase (MAPK) cascade, and cytoplasmic and nuclear effector functions. The entire pathway is conserved in diverse fungal species, while the Hog1 MAPK cascade is conserved even in higher eukaryotes including humans. This conservation is illustrated by the fact that the mammalian stress-responsive p38 MAPK can rescue the osmosensitivity of hog1Δ mutations in response to hyperosmotic challenge. As the HOG pathway is one of the best-understood eukaryotic signal transduction pathways, it is useful not only as a model for analysis of osmostress responses, but also as a model for mathematical analysis of signal transduction pathways. In this review, we have summarized the current understanding of both the upstream signaling mechanism and the downstream adaptive responses to hyperosmotic stress in yeast. PMID:23028184

Early-life stress origins of gastrointestinal disease: animal models, intestinal pathophysiology, and translational implications.

PubMed

Pohl, Calvin S; Medland, Julia E; Moeser, Adam J

2015-12-15

Early-life stress and adversity are major risk factors in the onset and severity of gastrointestinal (GI) disease in humans later in life. The mechanisms by which early-life stress leads to increased GI disease susceptibility in adult life remain poorly understood. Animal models of early-life stress have provided a foundation from which to gain a more fundamental understanding of this important GI disease paradigm. This review focuses on animal models of early-life stress-induced GI disease, with a specific emphasis on translational aspects of each model to specific human GI disease states. Early postnatal development of major GI systems and the consequences of stress on their development are discussed in detail. Relevant translational differences between species and models are highlighted. Copyright © 2015 the American Physiological Society.

EARLY HEAD START FAMILIES' EXPERIENCES WITH STRESS: UNDERSTANDING VARIATIONS WITHIN A HIGH-RISK, LOW-INCOME SAMPLE.

PubMed

Hustedt, Jason T; Vu, Jennifer A; Bargreen, Kaitlin N; Hallam, Rena A; Han, Myae

2017-09-01

The federal Early Head Start program provides a relevant context to examine families' experiences with stress since participants qualify on the basis of poverty and risk. Building on previous research that has shown variations in demographic and economic risks even among qualifying families, we examined possible variations in families' perceptions of stress. Family, parent, and child data were collected to measure stressors and risk across a variety of domains in families' everyday lives, primarily from self-report measures, but also including assay results from child cortisol samples. A cluster analysis was employed to examine potential differences among groups of Early Head Start families. Results showed that there were three distinct subgroups of families, with some families perceiving that they experienced very high levels of stress while others perceived much lower levels of stress despite also experiencing poverty and heightened risk. These findings have important implications in that they provide an initial step toward distinguishing differences in low-income families' experiences with stress, thereby informing interventions focused on promoting responsive caregiving as a possible mechanism to buffer the effects of family and social stressors on young children. © 2017 Michigan Association for Infant Mental Health.

Adiposity Is Associated with Blunted Cardiovascular, Neuroendocrine and Cognitive Responses to Acute Mental Stress

PubMed Central

Jones, Alexander; McMillan, Merlin R.; Jones, Russell W.; Kowalik, Grzegorz T.; Steeden, Jennifer A.; Deanfield, John E.; Pruessner, Jens C.; Taylor, Andrew M.; Muthurangu, Vivek

2012-01-01

Obesity and mental stress are potent risk factors for cardiovascular disease but their relationship with each other is unclear. Resilience to stress may differ according to adiposity. Early studies that addressed this are difficult to interpret due to conflicting findings and limited methods. Recent advances in assessment of cardiovascular stress responses and of fat distribution allow accurate assessment of associations between adiposity and stress responsiveness. We measured responses to the Montreal Imaging Stress Task in healthy men (N = 43) and women (N = 45) with a wide range of BMIs. Heart rate (HR) and blood pressure (BP) measures were used with novel magnetic resonance measures of stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) and arterial compliance to assess cardiovascular responses. Salivary cortisol and the number and speed of answers to mathematics problems in the task were used to assess neuroendocrine and cognitive responses, respectively. Visceral and subcutaneous fat was measured using T2 *-IDEAL. Greater BMI was associated with generalised blunting of cardiovascular (HR:β = −0.50 bpm.unit−1, P = 0.009; SV:β = −0.33 mL.unit−1, P = 0.01; CO:β = −61 mL.min−1.unit−1, P = 0.002; systolic BP:β = −0.41 mmHg.unit−1, P = 0.01; TPR:β = 0.11 WU.unit−1, P = 0.02), cognitive (correct answers: r = −0.28, P = 0.01; time to answer: r = 0.26, P = 0.02) and endocrine responses (cortisol: r = −0.25, P = 0.04) to stress. These associations were largely determined by visceral adiposity except for those related to cognitive performance, which were determined by both visceral and subcutaneous adiposity. Our findings suggest that adiposity is associated with centrally reduced stress responsiveness. Although this may mitigate some long-term health risks of stress responsiveness, reduced performance under stress may be a more immediate negative

Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

PubMed

Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

2016-02-01

Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

Absence of neurogenic response following robust predator-induced stress response.

PubMed

Lau, Catherine; Hebert, Mark; Vani, Marc A; Walling, Sue; Hayley, Shawn; Lagace, Diane C; Blundell, Jacqueline

2016-12-17

Traumatic events contribute to a variety of neuropsychiatric disorders including post-traumatic stress disorder (PTSD). Identifying the neural mechanisms that affect the stress response may improve treatment for stress-related disorders. Neurogenesis, the production of neurons, occurs within the adult brain and disturbances in neurogenesis in the subgranular zone (SGZ) of the hippocampus have been linked to mood and anxiety disorders. Chronic stress models have mainly suggested correlations with stress reducing adult SGZ neurogenesis, whereas acute stress models and those with a naturalistic component that are also associated with long-lasting behavioral changes have produced inconsistent results. Therefore, the goal of the current study was to examine the effects of acute predator stress on adult neurogenesis. Predator stress involved a single 10-min unprotected rat to cat exposure that has previously been shown to produce contextual fear, hyperarousal, and anxiety-like behavior lasting at least 3weeks. As expected, predator stress produced a stress response as detected by elevated corticosterone (CORT) levels immediately after stress. Despite this robust stress response, there was no significant difference between stressed and handled control rats in the number of proliferating or surviving cells as assessed by a 5-bromo-2'-deoxyuridine-immunoreactive (BrdU-IR) labeling 2h or 4weeks post-stress throughout the rostro-caudal axis of the SGZ, respectively. Additionally, 90% of 4-week-old BrdU-IR cells in both conditions expressed NeuN, suggesting no change in cell fate with stress exposure. Overall, these data give caution to the notion that acute predator stress can alter the production or survival of adult-generated cells. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Mechanical Stress Induces Biotic and Abiotic Stress Responses via a Novel cis-Element

PubMed Central

Walley, Justin W; Coughlan, Sean; Hudson, Matthew E; Covington, Michael F; Kaspi, Roy; Banu, Gopalan; Harmer, Stacey L; Dehesh, Katayoon

2007-01-01

Plants are continuously exposed to a myriad of abiotic and biotic stresses. However, the molecular mechanisms by which these stress signals are perceived and transduced are poorly understood. To begin to identify primary stress signal transduction components, we have focused on genes that respond rapidly (within 5 min) to stress signals. Because it has been hypothesized that detection of physical stress is a mechanism common to mounting a response against a broad range of environmental stresses, we have utilized mechanical wounding as the stress stimulus and performed whole genome microarray analysis of Arabidopsis thaliana leaf tissue. This led to the identification of a number of rapid wound responsive (RWR) genes. Comparison of RWR genes with published abiotic and biotic stress microarray datasets demonstrates a large overlap across a wide range of environmental stresses. Interestingly, RWR genes also exhibit a striking level and pattern of circadian regulation, with induced and repressed genes displaying antiphasic rhythms. Using bioinformatic analysis, we identified a novel motif overrepresented in the promoters of RWR genes, herein designated as the Rapid Stress Response Element (RSRE). We demonstrate in transgenic plants that multimerized RSREs are sufficient to confer a rapid response to both biotic and abiotic stresses in vivo, thereby establishing the functional involvement of this motif in primary transcriptional stress responses. Collectively, our data provide evidence for a novel cis-element that is distributed across the promoters of an array of diverse stress-responsive genes, poised to respond immediately and coordinately to stress signals. This structure suggests that plants may have a transcriptional network resembling the general stress signaling pathway in yeast and that the RSRE element may provide the key to this coordinate regulation. PMID:17953483

Mothers' Stress, Resilience and Early Intervention

ERIC Educational Resources Information Center

Margalit, M.; Kleitman, T.

2006-01-01

The aim of the study was to examine factors that predict maternal stress, reported by mothers whose infants were diagnosed as having developmental disabilities at the beginning of participating in an early intervention programme "Me and My Mommy" and after one year. A second goal was to identify and to portray a subgroup of resilient…

Early Detection of Salt Stress Damage by Biophotons in Red Bean Seedling

NASA Astrophysics Data System (ADS)

Ohya, Tomoyuki; Kurashige, Hideaki; Okabe, Hirotaka; Kai, Shoichi

2000-06-01

The optical detection of the stress damage to plants by NaCl solutions was attempted during germination of a seed and growth of a root. We compared the photon intensity of red beans before and after NaCl treatment and found that the photon intensity after NaCl treatment decreased as the NaCl concentration increased. For the saturated NaCl concentration (4.5 M), however, the observed photon intensity drastically increased, and the simultaneous destruction of cell membranes was observed. The intensity of biophoton emission from red beans showed characteristic change with salt concentrations. When the salt stress was applied to the red beans at an early growth stage, their root elongations were suppressed and photon intensity from the root decreased. This was not the case for the root at the late stage. This shows that biophoton intensity due to salt stress depends on not only NaCl concentration but also the growth stage of the plant. We may conclude that the extent of damage to roots by salt stress can be evaluated from biophoton response.

Alternative Splicing Control of Abiotic Stress Responses.

PubMed

Laloum, Tom; Martín, Guiomar; Duque, Paula

2018-02-01

Alternative splicing, which generates multiple transcripts from the same gene, is an important modulator of gene expression that can increase proteome diversity and regulate mRNA levels. In plants, this post-transcriptional mechanism is markedly induced in response to environmental stress, and recent studies have identified alternative splicing events that allow rapid adjustment of the abundance and function of key stress-response components. In agreement, plant mutants defective in splicing factors are severely impaired in their response to abiotic stress. Notably, mounting evidence indicates that alternative splicing regulates stress responses largely by targeting the abscisic acid (ABA) pathway. We review here current understanding of post-transcriptional control of plant stress tolerance via alternative splicing and discuss research challenges for the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

Smoking in young adulthood among African Americans: Interconnected effects of supportive parenting in early adolescence, proinflammatory epitype, and young adult stress.

PubMed

Beach, Steven R H; Lei, Man Kit; Brody, Gene H; Miller, Gregory E; Chen, Edith; Mandara, Jelani; Philibert, Robert A

2017-08-01

We examined two potentially interacting, connected pathways by which parental supportiveness during early adolescence (ages 1-13) may come to be associated with later African American young adult smoking. The first pathway is between parental supportiveness and young adult stress (age 19), with stress, in turn, predicting increased smoking at age 20. The second pathway is between supportive parenting and tumor necrosis factor (TNF) gene methylation (i.e., TNFm), a proinflammatory epitype, with low levels indicating greater inflammatory potential and forecasting increased risk for smoking in response to young adult stress. In a sample of 382 African American youth residing in rural Georgia, followed from early adolescence (age 10-11) to young adulthood (age 20), supportive parenting indirectly predicted smoking via associations with young adult stress, IE = -0.071, 95% confidence interval [-0.132, -0.010]. In addition, supportive parenting was associated with TNFm measured at age 20 (r = .177, p = .001). Further, lower TNFm was associated with a significantly steeper slope (b = 0.583, p = .003) of increased smoking in response to young adult stress compared to those with higher TNFm (b = 0.155, p = .291), indicating an indirect, amplifying role for supportive parenting via TNFm. The results suggest that supportive parenting in early adolescence may play a role in understanding the emergence of smoking in young adulthood.

Selection of reference genes for microRNA analysis associated to early stress response to handling and confinement in Salmo salar.

PubMed

Zavala, Eduardo; Reyes, Daniela; Deerenberg, Robert; Vidal, Rodrigo

2017-05-11

MicroRNAs are key non-coding RNA molecules that play a relevant role in the regulation of gene expression through translational repression and/or transcript cleavage during normal development and physiological adaptation processes like stress. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) has become the approach normally used to determine the levels of microRNAs. However, this approach needs the use of endogenous reference. An improper selection of endogenous references can result in confusing interpretation of data. The aim of this study was to identify and validate appropriate endogenous reference miRNA genes for normalizing RT-qPCR survey of miRNAs expression in four different tissues of Atlantic salmon, under handling and confinement stress conditions associated to early or primary stress response. Nine candidate reference normalizers, including microRNAs and nuclear genes, normally used in vertebrate microRNA expression studies were selected from literature, validated by RT-qPCR and analyzed by the algorithms geNorm and NormFinder. The results revealed that the ssa-miR-99-5p gene was the most stable overall and that ssa-miR-99-5p and ssa-miR-23a-5p genes were the best combination. Moreover, the suitability of ssa-miR-99-5p and ssa-miR-23a-5p as endogeneuos reference genes was demostrated by the expression analysis of ssa-miR-193-5p gene.

The therapeutic use of the relaxation response in stress-related diseases.

PubMed

Esch, Tobias; Fricchione, Gregory L; Stefano, George B

2003-02-01

The objective of this work was to investigate a possible (therapeutic) connection between the relaxation response (RR) and stress-related diseases. Further, common underlying molecular mechanisms and autoregulatory pathways were examined. For the question of (patho)physiology and significance of RR techniques in the treatment of stress-related diseases, we analyzed peer-reviewed references only. The RR has been shown to be an appropriate and relevant therapeutic tool to counteract several stress-related disease processes and certain health-restrictions, particularly in certain immunological, cardiovascular, and neurodegenerative diseases/mental disorders. Further, common underlying molecular mechanisms may exist that represent a connection between the stress response, pathophysiological findings in stress-related diseases, and physiological changes/autoregulatory pathways described in the RR. Here, constitutive or low-output nitric oxide (NO) production may be involved in a protective or ameliorating context, whereas inducible, high-output NO release may facilitate detrimental disease processes. In mild or early disease states, a high degree of biological and physiological flexibility may still be possible (dynamic balance). Here, the therapeutic use of RR techniques may be considered particularly relevant, and the observable (beneficial) effects may be exerted via activation of constitutive NO pathways. RR techniques, regularly part of professional stress management or mind/body medical settings, represent an important tool to be added to therapeutic strategies dealing with stress-related diseases. Moreover, as part of 'healthy' life-style modifications, they may serve primary (or secondary) prevention. Further studies are necessary to elucidate the complex physiology underlying the RR and its impact upon stress-related disease states.

Adulthood stress responses in rats are variably altered as a factor of adolescent stress exposure.

PubMed

Moore, Nicole L T; Altman, Daniel E; Gauchan, Sangeeta; Genovese, Raymond F

2016-05-01

Stress exposure during development may influence adulthood stress response severity. The present study investigates persisting effects of two adolescent stressors upon adulthood response to predator exposure (PE). Rats were exposed to underwater trauma (UWT) or PE during adolescence, then to PE after reaching adulthood. Rats were then exposed to predator odor (PO) to test responses to predator cues alone. Behavioral and neuroendocrine assessments were conducted to determine acute effects of each stress experience. Adolescent stress altered behavioral response to adulthood PE. Acoustic startle response was blunted. Bidirectional changes in plus maze exploration were revealed as a factor of adolescent stress type. Neuroendocrine response magnitude did not predict severity of adolescent or adult stress response, suggesting that different adolescent stress events may differentially alter developmental outcomes regardless of acute behavioral or neuroendocrine response. We report that exposure to two different stressors in adolescence may differentially affect stress response outcomes in adulthood. Acute response to an adolescent stressor may not be consistent across all stressors or all dependent measures, and may not predict alterations in developmental outcomes pertaining to adulthood stress exposure. Further studies are needed to characterize factors underlying long-term effects of a developmental stressor.

Long-term dysregulation of brain corticotrophin and glucocorticoid receptors and stress reactivity by single early-life pain experience in male and female rats.

PubMed

Victoria, Nicole C; Inoue, Kiyoshi; Young, Larry J; Murphy, Anne Z

2013-12-01

Inflammatory pain experienced on the day of birth (postnatal day 0: PD0) significantly dampens behavioral responses to stress- and anxiety-provoking stimuli in adult rats. However, to date, the mechanisms by which early life pain permanently alters adult stress responses remain unknown. The present studies examined the impact of inflammatory pain, experienced on the day of birth, on adult expression of receptors or proteins implicated in the activation and termination of the stress response, including corticotrophin releasing factor receptors (CRFR1 and CRFR2) and glucocorticoid receptor (GR). Using competitive receptor autoradiography, we show that Sprague Dawley male and female rat pups administered 1% carrageenan into the intraplantar surface of the hindpaw on the day of birth have significantly decreased CRFR1 binding in the basolateral amygdala and midbrain periaqueductal gray in adulthood. In contrast, CRFR2 binding, which is associated with stress termination, was significantly increased in the lateral septum and cortical amygdala. GR expression, measured with in situ hybridization and immunohistochemistry, was significantly increased in the paraventricular nucleus of the hypothalamus and significantly decreased in the hippocampus of neonatally injured adults. In parallel, acute stress-induced corticosterone release was significantly attenuated and returned to baseline more rapidly in adults injured on PD0 in comparison to controls. Collectively, these data show that early life pain alters neural circuits that regulate responses to and neuroendocrine recovery from stress, and suggest that pain experienced by infants in the Neonatal Intensive Care Unit may permanently alter future responses to anxiety- and stress-provoking stimuli. Published by Elsevier Ltd.

Early adaption to the antarctic environment at dome C: consequences on stress-sensitive innate immune functions.

PubMed

Feuerecker, Matthias; Crucian, Brian; Salam, Alex P; Rybka, Ales; Kaufmann, Ines; Moreels, Marjan; Quintens, Roel; Schelling, Gustav; Thiel, Manfred; Baatout, Sarah; Sams, Clarence; Choukèr, Alexander

2014-09-01

Abstract Feuerecker, Matthias, Brian Crucian, Alex P. Salam, Ales Rybka, Ines Kaufmann, Marjan Moreels, Roel Quintens, Gustav Schelling, Manfred Thiel, Sarah Baatout, Clarence Sams, and Alexander Choukèr. Early adaption in the Antarctic environment at Dome C: Consequences on stress-sensitive innate immune functions. High Alt Med Biol 15:341-348, 2014.-Purpose/Aims: Medical reports of Antarctic expeditions indicate that health is affected under these extreme conditions. The present study at CONCORDIA-Station (Dome C, 3233 m) seeks to investigate the early consequences of confinement and hypobaric hypoxia on the human organism. Nine healthy male participants were included in this study. Data collection occurred before traveling to Antarctica (baseline), and at 1 week and 1 month upon arrival. Investigated parameters included basic physiological variables, psychological stress tests, cell blood count, stress hormones, and markers of innate immune functions in resting and stimulated immune cells. By testing for the hydrogen peroxide (H2O2) production of stimulated polymorphonuclear leukocytes (PMNs), the effects of the hypoxia-adenosine-sensitive immune modulatory pathways were examined. As compared to baseline data, reduced oxygen saturation, hemoconcentration, and an increase of secreted catecholamines was observed, whereas no psychological stress was seen. Upon stimulation, the activity of PMNs and L-selectin shedding was mitigated after 1 week. Endogenous adenosine concentration was elevated during the early phase. In summary, living conditions at high altitude influence the innate immune system's response. After 1 month, some of the early effects on the human organism were restored. As this early adaptation is not related to psychological stress, the changes observed are likely to be induced by environmental stressors, especially hypoxia. As hypoxia is triggering ATP-catabolism, leading to elevated endogenous adenosine concentrations, this and the increased

Sex differences in stress-induced visceral hypersensitivity following early life adversity: a two hit model.

PubMed

Prusator, D K; Greenwood-Van Meerveld, B

2016-12-01

Early life adversity (ELA) has been indicated as a risk factor for the development of stress axis dysfunction in adulthood, specifically in females. We previously showed that unpredictable ELA induces visceral hyperalgesia in adult female rats. It remains to be determined whether ELA alters visceral nociceptive responses to stress in adulthood. The current study tested the hypothesis that following ELA, exposure to an adulthood stressor, or second hit, serves as a risk factor for exaggerated stress-induced visceral hypersensitivity that is sex-specific. Following ELA, adult stress was induced via a single exposure (acute) or repetitive daily exposure, 1 h/day for 7 days (chronic), to water avoidance stress (WAS). Acute WAS increased pain behaviors in all adult female rats, however, females that experienced unpredictable ELA exhibited significantly more pain behaviors compared to those exposed to predictable ELA or controls. Following chronic WAS, all adult females exhibited increased pain responses, however, an exaggerated response was observed in rats exposed to unpredictable or predictable ELA compared to controls. Similarly, in adult male rats exposure to acute or chronic WAS increased pain behaviors, however, there were no differences in pain behaviors between ELA groups. This study highlights a novel consequence of ELA on stress-induced visceral nociception in adulthood that is sex-specific. More importantly, our study suggests that ELA not only serves as a risk factor for development of chronic pain in adulthood, but also serves as a predisposition for worsening of visceral pain following adult stress in female rats. © 2016 John Wiley & Sons Ltd.

Stress proteins and the immune response.

PubMed

Moseley, P

2000-07-25

The heat shock or stress response is one of the most highly conserved adaptive responses in nature. In single cell organisms, the stress response confers tolerance to a variety of stresses including hyperthermia, hyperoxia, hypoxia, and other perturbations, which alter protein synthesis. This tolerance phenomenon is also extremely important in the multicellular organism, resulting in not only thermal tolerance, but also resistance to stresses of the whole organism such as ischemia-reperfusion injury. Moreover, recent data indicates that these stress proteins have the ability to modulate the cellular immune response. Although the terms heat shock proteins (HSPs) and stress proteins are often used interchangeably, the term stress proteins includes the HSPs, the glucose-regulated proteins (GRPs) and ubiquitin. The stress proteins may be grouped by molecular weight ranging from the large 110 kDa HSP110 to ubiquitin at 8 kDa. These proteins serve as cellular chaperones, participating in protein synthesis and transport through the various cellular compartments. Because these proteins have unique cellular localizations, the chaperone function of the stress proteins often involves a transfer of peptides between stress proteins as the peptide is moved between cellular compartments. For example, HSP70 is a cytosolic and nuclear chaperone, which is critical for the transfer of cellular peptides in the mitochondrion through a hand-off that involves mitochondrial HSP60 at the inner mitochondrial membrane. Similarly, cytosolic proteins are transferred from HSP70 to gp96 as they move into the endoplasmic reticulum. The central role of the stress proteins in the transfer of peptides through the cell may be responsible for the recently recognized importance of the stress proteins in the modulation of the immune system [Feder, M.E., Hofmann, G.E., 1999. Heat-shock proteins, molecular chaperones, and the stress response: evolutionary and ecological physiology. Annu. Rev. Physiol. 61

Sociotropic cognition moderates stress-induced cardiovascular responsiveness in college women.

PubMed

Sauro, M D; Jorgensen, R S; Larson, C A; Frankowski, J J; Ewart, C K; White, J

2001-10-01

This study examined the moderating effects of sociotropic cognition (SC), a nondefensive need for approval, on stress-induced cardiovascular responsiveness (CVR) in women. Sixty-seven college-age females had blood pressure (BP) and heart rate (HR) monitored during baseline, anticipation, story-telling (where participants were randomly assigned to a low or high threat condition), and recovery periods. SC showed a positive association with CVR only in the high interpersonal threat context during task and early stages of the recovery periods. SC was positively correlated with such variables as anxiety, ruminative style, dysphoria, and anger. This is the first report examining the moderating effects of SC on interpersonal stress-induced CVR prior to, during, and following a task, using an explicit manipulation of social evaluation. The data help define risk factors for CVR in women, which may aid in the understanding of how emotions and stress affect physical health and well-being.

Transcriptional 'memory' of a stress: transient chromatin and memory (epigenetic) marks at stress-response genes.

PubMed

Avramova, Zoya

2015-07-01

Drought, salinity, extreme temperature variations, pathogen and herbivory attacks are recurring environmental stresses experienced by plants throughout their life. To survive repeated stresses, plants provide responses that may be different from their response during the first encounter with the stress. A different response to a similar stress represents the concept of 'stress memory'. A coordinated reaction at the organismal, cellular and gene/genome levels is thought to increase survival chances by improving the plant's tolerance/avoidance abilities. Ultimately, stress memory may provide a mechanism for acclimation and adaptation. At the molecular level, the concept of stress memory indicates that the mechanisms responsible for memory-type transcription during repeated stresses are not based on repetitive activation of the same response pathways activated by the first stress. Some recent advances in the search for transcription 'memory factors' are discussed with an emphasis on super-induced dehydration stress memory response genes in Arabidopsis. © 2015 The Author The Plant Journal © 2015 John Wiley & Sons Ltd.

Opposite Effects of Stress on Pain Modulation Depend on the Magnitude of Individual Stress Response.

PubMed

Geva, Nirit; Defrin, Ruth

2018-04-01

The effect of acute stress on pain threshold and intolerance threshold are reported as producing either hypoalgesia or hyperalgesia. Yet, the contribution of individual stress reactivity in this respect has not been established. The aim was to test 2 pain modulation paradigms under acute stress manipulation, to our knowledge, for the first time, to study whether stress differentially affects pain modulation, and whether the effect is related to individual stress response. Participants were 31 healthy subjects. Conditioned pain modulation (CPM) and pain adaptation were measured before and after inducing an acute stress response using the Montreal Imaging Stress Task. Subjects' stress response was evaluated according to salivary cortisol, autonomic function, and perceived stress and anxiety. The Montreal Imaging Stress Task induced a validated stress response. On a group level, stress induced reduction in CPM magnitude and increase in pain adaptation compared with baseline. These responses correlated with stress reactivity. When the group was subdivided according to stress reactivity, only high stress responders exhibited reduced CPM whereas only low stress responders exhibited increased pain adaptation. The results suggest that acute stress may induce opposite effects on pain modulation, depending on individual stress reactivity magnitude, with an advantage to low stress responders. This study evaluated the effect of acute stress on pain modulation. Pain modulation under stress is affected by individual stress responsiveness; decreased CPM occurs in high stress responders whereas increased pain adaptation occurs in low stress responders. Identification of high stress responders may promote better pain management. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

Early identification of posttraumatic stress following military deployment: Application of machine learning methods to a prospective study of Danish soldiers.

PubMed

Karstoft, Karen-Inge; Statnikov, Alexander; Andersen, Søren B; Madsen, Trine; Galatzer-Levy, Isaac R

2015-09-15

Pre-deployment identification of soldiers at risk for long-term posttraumatic stress psychopathology after home coming is important to guide decisions about deployment. Early post-deployment identification can direct early interventions to those in need and thereby prevents the development of chronic psychopathology. Both hold significant public health benefits given large numbers of deployed soldiers, but has so far not been achieved. Here, we aim to assess the potential for pre- and early post-deployment prediction of resilience or posttraumatic stress development in soldiers by application of machine learning (ML) methods. ML feature selection and prediction algorithms were applied to a prospective cohort of 561 Danish soldiers deployed to Afghanistan in 2009 to identify unique risk indicators and forecast long-term posttraumatic stress responses. Robust pre- and early postdeployment risk indicators were identified, and included individual PTSD symptoms as well as total level of PTSD symptoms, previous trauma and treatment, negative emotions, and thought suppression. The predictive performance of these risk indicators combined was assessed by cross-validation. Together, these indicators forecasted long term posttraumatic stress responses with high accuracy (pre-deployment: AUC = 0.84 (95% CI = 0.81-0.87), post-deployment: AUC = 0.88 (95% CI = 0.85-0.91)). This study utilized a previously collected data set and was therefore not designed to exhaust the potential of ML methods. Further, the study relied solely on self-reported measures. Pre-deployment and early post-deployment identification of risk for long-term posttraumatic psychopathology are feasible and could greatly reduce the public health costs of war. Copyright © 2015 Elsevier B.V. All rights reserved.

Maternal Separation Enhances Neuronal Activation and Cardiovascular Responses to Acute Stress in Borderline Hypertensive Rats

PubMed Central

Sanders, Brian J.; Anticevic, Alan

2007-01-01

There is much evidence suggesting early life events, such has handling or repeated separations from the nest, can have a long term effect on the biological and behavioral development of rats. The current study examined the effect of repeated maternal separation (MS) on the behavioral, cardiovascular, and neurobiological responses to stress in subjects vulnerable to environmental stressors as adults. Borderline hypertensive rats (BHR), which are the first generation offspring of spontaneously hyperternsive and Wistar-Kyoto rats, were separated from the dams for 3 hours per day from post-natal day 1 through 14. Non-separated controls remained in the home cage. When allowed to explore the open field chamber for 60 minutes as adults, MS subjects had significantly greater locomotor activity compared to controls. All subjects were exposed to 30 minutes of restraint stress during which time mean arterial pressure (MAP) and heart rate (HR) were measured. Although both groups had comparable increases in MAP, MS animals displayed significantly higher HR throughout the stress period. Finally, MS subjects had significantly more stress-induced Fos positive cells, an estimate of neuronal activation, in the central nucleus of the amygdala (CeA), paraventricular nucleus of the hypothalamus (PVN), and the bed nucleus of the stria terminalis (BNST), each of which plays an important role in organizing the biobehavioral response to stress. These results suggest that maternal separation can further enhance stress reactivity in this model and may represent a useful approach for studying the relationship between early life events and future vulnerability to stressful situations. PMID:17604851

Toward Understanding How Early-Life Stress Reprograms Cognitive and Emotional Brain Networks.

PubMed

Chen, Yuncai; Baram, Tallie Z

2016-01-01

Vulnerability to emotional disorders including depression derives from interactions between genes and environment, especially during sensitive developmental periods. Adverse early-life experiences provoke the release and modify the expression of several stress mediators and neurotransmitters within specific brain regions. The interaction of these mediators with developing neurons and neuronal networks may lead to long-lasting structural and functional alterations associated with cognitive and emotional consequences. Although a vast body of work has linked quantitative and qualitative aspects of stress to adolescent and adult outcomes, a number of questions are unclear. What distinguishes 'normal' from pathologic or toxic stress? How are the effects of stress transformed into structural and functional changes in individual neurons and neuronal networks? Which ones are affected? We review these questions in the context of established and emerging studies. We introduce a novel concept regarding the origin of toxic early-life stress, stating that it may derive from specific patterns of environmental signals, especially those derived from the mother or caretaker. Fragmented and unpredictable patterns of maternal care behaviors induce a profound chronic stress. The aberrant patterns and rhythms of early-life sensory input might also directly and adversely influence the maturation of cognitive and emotional brain circuits, in analogy to visual and auditory brain systems. Thus, unpredictable, stress-provoking early-life experiences may influence adolescent cognitive and emotional outcomes by disrupting the maturation of the underlying brain networks. Comprehensive approaches and multiple levels of analysis are required to probe the protean consequences of early-life adversity on the developing brain. These involve integrated human and animal-model studies, and approaches ranging from in vivo imaging to novel neuroanatomical, molecular, epigenomic, and computational

Induction of the plasticity-associated immediate early gene Arc by stress and hallucinogens: role of brain-derived neurotrophic factor.

PubMed

Benekareddy, Madhurima; Nair, Amrita R; Dias, Brian G; Suri, Deepika; Autry, Anita E; Monteggia, Lisa M; Vaidya, Vidita A

2013-03-01

Exposure to stress and hallucinogens in adulthood evokes persistent alterations in neurocircuitry and emotional behaviour. The structural and functional changes induced by stress and hallucinogen exposure are thought to involve transcriptional alterations in specific effector immediate early genes. The immediate early gene, activity regulated cytoskeletal-associated protein (Arc), is important for both activity and experience dependent plasticity. We sought to examine whether trophic factor signalling through brain-derived neurotrophic factor (BDNF) contributes to the neocortical regulation of Arc mRNA in response to distinct stimuli such as immobilization stress and the hallucinogen 2,5-dimethoxy-4-iodoamphetamine (DOI). Acute exposure to either immobilization stress or DOI induced Arc mRNA levels within the neocortex. BDNF infusion into the neocortex led to a robust up-regulation of local Arc transcript expression. Further, baseline Arc mRNA expression in the neocortex was significantly decreased in inducible BDNF knockout mice with an adult-onset, forebrain specific BDNF loss. The induction of Arc mRNA levels in response to both acute immobilization stress or a single administration of DOI was significantly attenuated in the inducible BDNF knockout mice. Taken together, our results implicate trophic factor signalling through BDNF in the regulation of cortical Arc mRNA expression, both under baseline conditions and following stress and hallucinogen exposure. These findings suggest the possibility that the regulation of Arc expression via BDNF provides a molecular substrate for the structural and synaptic plasticity observed following stimuli such as stress and hallucinogens.

[Regulation of heat shock gene expression in response to stress].

PubMed

Garbuz, D G

2017-01-01

Heat shock (HS) genes, or stress genes, code for a number of proteins that collectively form the most ancient and universal stress defense system. The system determines the cell capability of adaptation to various adverse factors and performs a variety of auxiliary functions in normal physiological conditions. Common stress factors, such as higher temperatures, hypoxia, heavy metals, and others, suppress transcription and translation for the majority of genes, while HS genes are upregulated. Transcription of HS genes is controlled by transcription factors of the HS factor (HSF) family. Certain HSFs are activated on exposure to higher temperatures or other adverse factors to ensure stress-induced HS gene expression, while other HSFs are specifically activated at particular developmental stages. The regulation of the main mammalian stress-inducible factor HSF1 and Drosophila melanogaster HSF includes many components, such as a variety of early warning signals indicative of abnormal cell activity (e.g., increases in intracellular ceramide, cytosolic calcium ions, or partly denatured proteins); protein kinases, which phosphorylate HSFs at various Ser residues; acetyltransferases; and regulatory proteins, such as SUMO and HSBP1. Transcription factors other than HSFs are also involved in activating HS gene transcription; the set includes D. melanogaster GAF, mammalian Sp1 and NF-Y, and other factors. Transcription of several stress genes coding for molecular chaperones of the glucose-regulated protein (GRP) family is predominantly regulated by another stress-detecting system, which is known as the unfolded protein response (UPR) system and is activated in response to massive protein misfolding in the endoplasmic reticulum and mitochondrial matrix. A translational fine tuning of HS protein expression occurs via changing the phosphorylation status of several proteins involved in translation initiation. In addition, specific signal sequences in the 5'-UTRs of some HS

Extraversion and cardiovascular responses to recurrent social stress: Effect of stress intensity.

PubMed

Lü, Wei; Xing, Wanying; Hughes, Brian M; Wang, Zhenhong

2017-10-28

The present study sought to establish whether the effects of extraversion on cardiovascular responses to recurrent social stress are contingent on stress intensity. A 2×5×1 mixed-factorial experiment was conducted, with social stress intensity as a between-subject variable, study phase as a within-subject variable, extraversion as a continuous independent variable, and cardiovascular parameter (HR, SBP, DBP, or RSA) as a dependent variable. Extraversion (NEO-FFI), subjective stress, and physiological stress were measured in 166 undergraduate students randomly assigned to undergo moderate (n=82) or high-intensity (n=84) social stress (a public speaking task with different levels of social evaluation). All participants underwent continuous physiological monitoring while facing two consecutive stress exposures distributed across five laboratory phases: baseline, stress exposure 1, post-stress 1, stress exposure 2, post-stress 2. Results indicated that under moderate-intensity social stress, participants higher on extraversion exhibited lesser HR reactivity to stress than participants lower on extraversion, while under high-intensity social stress, they exhibited greater HR, SBP, DBP and RSA reactivity. Under both moderate- and high-intensity social stress, participants higher on extraversion exhibited pronounced SBP and DBP response adaptation to repeated stress, and showed either better degree of HR recovery or greater amount of SBP and DBP recovery after stress. These findings suggest that individuals higher on extraversion exhibit physiological flexibility to cope with social challenges and benefit from adaptive cardiovascular responses. Copyright © 2017 Elsevier B.V. All rights reserved.

Obesity induced alterations in redox homeostasis and oxidative stress are present from an early age

PubMed Central

Lechuga-Sancho, Alfonso M.; Gallego-Andujar, David; Ruiz-Ocaña, Pablo; Visiedo, Francisco M.; Saez-Benito, Ana; Schwarz, Mónica; Segundo, Carmen

2018-01-01

Objectives Oxidative stress and inflammation have been postulated as underlying mechanisms for the development of obesity-related insulin resistance. This association however, remains elusive especially in childhood. We sought to investigate this relation by measuring oxidative stress and antioxidant response biomarkers, before and during an oral glucose tolerance test (OGTT), in different biological samples from obese children. Subjects 24 children were recruited for the study, (18 obese and 6 controls). After OGTT, the obese group was subdivided in two, according to whether or not carbohydrate metabolic impairment (Ob.IR+, Ob.IR-; respectively) was found. Different biomarkers were analyzed after fasting (T = 0) and during an OGTT (T = 60 and 120 min). Lipoperoxides were measured in plasma, erythrocytes, and urine; while advanced glycation end products were determined in plasma, and redox status (GSH/GSSG ratio) in erythrocytes. Results We found marked differences in the characterization of the oxidative status in urine and erythrocytes, and in the dynamics of the antioxidant response during OGTT. Specifically, Ob.IR+ children show increased oxidative stress, deficient antioxidant response and a significant imbalance in redox status, in comparison to controls and Ob.IR- children. Conclusion Obese children with insulin resistance show increased levels of oxidative stress biomarkers, and a stunted antioxidant response to an OGTT leading to increased oxidative stress after a single glucose load, as detected in erythrocytes, but not in plasma. We propose erythrocytes as sensors of early and acute changes in oxidative stress associated with insulin resistance in childhood obesity. This is a pilot study, performed with a limited sample size, so data should be interpreted with caution until reproduced. PMID:29370267

The effect of early-life stress on airway inflammation in adult mice.

PubMed

Vig, Rattanjeet; Gordon, John R; Thébaud, Bernard; Befus, A Dean; Vliagoftis, Harissios

2010-01-01

Neonatal stress induces permanent physiological changes that may influence the immune system. Early-life stress increases asthma disease severity in children. We investigated the effects of early-life stress on allergic airway inflammation using a murine model of asthma coupled to maternal separation as an early-life stress stimulus. Maternally separated (MS) and unseparated control (CON) mice were sensitized with ovalbumin (OVA) beginning at day 31 after birth. Challenging mice with OVA increased airway hyperresponsiveness (AHR) and the number of inflammatory cells recovered in the bronchoalveolar lavage (BAL), compared to saline-challenged mice. Challenging MS mice with OVA resulted in less total inflammatory cells, eosinophils, interferon-gamma, and interleukin-4 in BAL compared to CON mice. However, MS mice challenged with OVA exhibited AHR similar to CON mice challenged with OVA. In contrast, an enhanced stress protocol (MS+) involving removal of pups from their home cages following the removal of the dam resulted in inflammatory cell accumulation and cytokine levels in the BAL similar to CON mice and higher than MS mice. These findings indicate that the effect of early-life psychological factors on the development of airway inflammatory diseases such as asthma is very complex and depends on the quality of the psychological stress stimulus.

Construction and application of EST library from Setaria italica in response to dehydration stress.

PubMed

Zhang, Jinpeng; Liu, Tingsong; Fu, Junjie; Zhu, Yun; Jia, Jinping; Zheng, Jun; Zhao, Yinhe; Zhang, Ying; Wang, Guoying

2007-07-01

Foxtail millet is a gramineous crop with low water requirement. Despite its high water use efficiency, less attention has been paid to the molecular genetics of foxtail millet. This article reports the construction of subtracted cDNA libraries from foxtail millet seedlings under dehydration stress and the expression profile analysis of 1947 UniESTs from the subtracted cDNA libraries by a cDNA microarray. The results showed that 95 and 57 ESTs were upregulated by dehydration stress, respectively, in roots and shoots of seedlings and that 10 and 27 ESTs were downregulated, respectively, in roots and shoots. The expression profile analysis showed that genes induced in foxtail millet roots were different from those in shoots during dehydration stress and that the early response to dehydration stress in foxtail millet roots was the activation of the glycolysis metabolism. Moreover, protein degradation pathway may also play a pivotal role in drought-tolerant responses of foxtail millet. Finally, Northern blot analysis validated well the cDNA microarray data.

Transgenerational transmission of a stress-coping phenotype programmed by early-life stress in the Japanese quail

PubMed Central

Zimmer, Cédric; Larriva, Maria; Boogert, Neeltje J.; Spencer, Karen A.

2017-01-01

An interesting aspect of developmental programming is the existence of transgenerational effects that influence offspring characteristics and performance later in life. These transgenerational effects have been hypothesized to allow individuals to cope better with predictable environmental fluctuations and thus facilitate adaptation to changing environments. Here, we test for the first time how early-life stress drives developmental programming and transgenerational effects of maternal exposure to early-life stress on several phenotypic traits in their offspring in a functionally relevant context using a fully factorial design. We manipulated pre- and/or post-natal stress in both Japanese quail mothers and offspring and examined the consequences for several stress-related traits in the offspring generation. We show that pre-natal stress experienced by the mother did not simply affect offspring phenotype but resulted in the inheritance of the same stress-coping traits in the offspring across all phenotypic levels that we investigated, shaping neuroendocrine, physiological and behavioural traits. This may serve mothers to better prepare their offspring to cope with later environments where the same stressors are experienced. PMID:28387355

STRESS ETHYLENE PRODUCTION - A MEASURE OF PLANT RESPONSE TO STRESS

EPA Science Inventory

Contents: Introduction to the symposium; Environmental data acquisition; Plant organ chambers in plant physiology field research; Interpreting the metabolic responses of plants to water stress; Stress ethylene production.

Long-term changes in cognitive bias and coping response as a result of chronic unpredictable stress during adolescence.

PubMed

Chaby, Lauren E; Cavigelli, Sonia A; White, Amanda; Wang, Kayllie; Braithwaite, Victoria A

2013-01-01

Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid "stress" hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision-making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g., isolation, crowding, cage tilt) were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias [F (1, 12) = 5.000, P < 0.05], altered coping response [T (1, 14) = 2.216, P = 0.04], and accelerated decision-making [T (1, 14) = 3.245, P = 0.01]. Exposure to chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object [T (1, 14) = 2.240, P = 0.04; T (1, 14) = 2.419, P = 0.03, respectively]. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions.

Effect of Pet Dogs on Children’s Perceived Stress and Cortisol Stress Response

PubMed Central

Kertes, Darlene A.; Liu, Jingwen; Hall, Nathan J.; Hadad, Natalie A.; Wynne, Clive D. L.; Bhatt, Samarth S.

2016-01-01

The present study tested whether pet dogs have stress-buffering effects for children during a validated laboratory-based protocol, the Trier Social Stress Test for Children (TSST-C). Participants were 101 children aged 7–12 years with their primary caregivers and pet dogs. Children were randomly assigned in the TSST-C to a pet present condition or one of two comparison conditions: parent present or no support figure present. Baseline, response, and recovery indices of perceived stress and cortisol levels were computed based on children’s self-reported feelings of stress and salivary cortisol. Results indicated that in the alone (no social support) condition, children showed the expected rise for both perceived stress and cortisol response to stress. Pet dog presence significantly buffered the perceived stress response in comparison to children in the alone and parent present conditions. No main condition effect was observed for cortisol; however, for children experiencing the stressor with their pet present, lower cortisol response to stress was associated with more child-initiated petting and less dog proximity-seeking behavior. The results support the notion that pet dogs can provide socio-emotional benefits for children via stress buffering. PMID:28439150

Stat5 Signaling Specifies Basal versus Stress Erythropoietic Responses through Distinct Binary and Graded Dynamic Modalities

PubMed Central

Porpiglia, Ermelinda; Hidalgo, Daniel; Koulnis, Miroslav; Tzafriri, Abraham R.; Socolovsky, Merav

2012-01-01

Erythropoietin (Epo)-induced Stat5 phosphorylation (p-Stat5) is essential for both basal erythropoiesis and for its acceleration during hypoxic stress. A key challenge lies in understanding how Stat5 signaling elicits distinct functions during basal and stress erythropoiesis. Here we asked whether these distinct functions might be specified by the dynamic behavior of the Stat5 signal. We used flow cytometry to analyze Stat5 phosphorylation dynamics in primary erythropoietic tissue in vivo and in vitro, identifying two signaling modalities. In later (basophilic) erythroblasts, Epo stimulation triggers a low intensity but decisive, binary (digital) p-Stat5 signal. In early erythroblasts the binary signal is superseded by a high-intensity graded (analog) p-Stat5 response. We elucidated the biological functions of binary and graded Stat5 signaling using the EpoR-HM mice, which express a “knocked-in” EpoR mutant lacking cytoplasmic phosphotyrosines. Strikingly, EpoR-HM mice are restricted to the binary signaling mode, which rescues these mice from fatal perinatal anemia by promoting binary survival decisions in erythroblasts. However, the absence of the graded p-Stat5 response in the EpoR-HM mice prevents them from accelerating red cell production in response to stress, including a failure to upregulate the transferrin receptor, which we show is a novel stress target. We found that Stat5 protein levels decline with erythroblast differentiation, governing the transition from high-intensity graded signaling in early erythroblasts to low-intensity binary signaling in later erythroblasts. Thus, using exogenous Stat5, we converted later erythroblasts into high-intensity graded signal transducers capable of eliciting a downstream stress response. Unlike the Stat5 protein, EpoR expression in erythroblasts does not limit the Stat5 signaling response, a non-Michaelian paradigm with therapeutic implications in myeloproliferative disease. Our findings show how the binary and

Exposure and peritraumatic response as predictors of posttraumatic stress in children following the 1995 Oklahoma City bombing.

PubMed

Pfefferbaum, Betty; Doughty, Debby E; Reddy, Chandrashekar; Patel, Nilam; Gurwitch, Robin H; Nixon, Sara Jo; Tivis, Rick D

2002-09-01

Studies have demonstrated a positive relationship between exposure and posttraumatic stress, but one's subjective appraisal of danger and threat at the time of exposure may be a better predictor of posttraumatic stress than more objective measures of exposure. We examined the role of peritraumatic response in posttraumatic stress reactions in over 2,000 middle school children 7 weeks after the 1995 Oklahoma City, Oklahoma, bombing. While many children reported hearing and feeling the blast and knowing direct victims, most were in school at the time of the explosion and therefore were not in direct physical proximity to the incident. Physical, interpersonal, and television exposure accounted for 12% of the total variance in our measure of posttraumatic stress when peritraumatic response was ignored. Peritraumatic response and television exposure accounted for 25% of the total variance, and physical and interpersonal exposure were not significant in this context. These findings suggest the importance of peritraumatic response in children's reactions to terrorism. These early responses can be used to help determine which children may experience difficulty over time.

Everyday stress response targets in the science of behavior change.

PubMed

Smyth, Joshua M; Sliwinski, Martin J; Zawadzki, Matthew J; Scott, Stacey B; Conroy, David E; Lanza, Stephanie T; Marcusson-Clavertz, David; Kim, Jinhyuk; Stawski, Robert S; Stoney, Catherine M; Buxton, Orfeu M; Sciamanna, Christopher N; Green, Paige M; Almeida, David M

2018-02-01

Stress is an established risk factor for negative health outcomes, and responses to everyday stress can interfere with health behaviors such as exercise and sleep. In accordance with the Science of Behavior Change (SOBC) program, we apply an experimental medicine approach to identifying stress response targets, developing stress response assays, intervening upon these targets, and testing intervention effectiveness. We evaluate an ecologically valid, within-person approach to measuring the deleterious effects of everyday stress on physical activity and sleep patterns, examining multiple stress response components (i.e., stress reactivity, stress recovery, and stress pile-up) as indexed by two key response indicators (negative affect and perseverative cognition). Our everyday stress response assay thus measures multiple malleable stress response targets that putatively shape daily health behaviors (physical activity and sleep). We hypothesize that larger reactivity, incomplete recovery, and more frequent stress responses (pile-up) will negatively impact health behavior enactment in daily life. We will identify stress-related reactivity, recovery, and response in the indicators using coordinated analyses across multiple naturalistic studies. These results are the basis for developing a new stress assay and replicating the initial findings in a new sample. This approach will advance our understanding of how specific aspects of everyday stress responses influence health behaviors, and can be used to develop and test an innovative ambulatory intervention for stress reduction in daily life to enhance health behaviors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neuronal Responses to Physiological Stress

PubMed Central

Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

2012-01-01

Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, due to an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level. PMID:23112806

Biotechnological approaches to study plant responses to stress.

PubMed

Pérez-Clemente, Rosa M; Vives, Vicente; Zandalinas, Sara I; López-Climent, María F; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized.

Biotechnological Approaches to Study Plant Responses to Stress

PubMed Central

Pérez-Clemente, Rosa M.; Vives, Vicente; Zandalinas, Sara I.; López-Climent, María F.; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized. PMID:23509757

Smyd1 Facilitates Heart Development by Antagonizing Oxidative and ER Stress Responses

PubMed Central

Park, Chong Yon; Harriss, June; Pierce, Stephanie A.; Dekker, Joseph D.; Valenzuela, Nicolas; Srivastava, Deepak; Schwartz, Robert J.; Stewart, M. David; Tucker, Haley O.

2015-01-01

Smyd1/Bop is an evolutionary conserved histone methyltransferase previously shown by conventional knockout to be critical for embryonic heart development. To further explore the mechanism(s) in a cell autonomous context, we conditionally ablated Smyd1 in the first and second heart fields of mice using a knock-in (KI) Nkx2.5-cre driver. Robust deletion of floxed-Smyd1 in cardiomyocytes and the outflow tract (OFT) resulted in embryonic lethality at E9.5, truncation of the OFT and right ventricle, and additional defects consistent with impaired expansion and proliferation of the second heart field (SHF). Using a transgenic (Tg) Nkx2.5-cre driver previously shown to not delete in the SHF and OFT, early embryonic lethality was bypassed and both ventricular chambers were formed; however, reduced cardiomyocyte proliferation and other heart defects resulted in later embryonic death at E11.5-12.5. Proliferative impairment prior to both early and mid-gestational lethality was accompanied by dysregulation of transcripts critical for endoplasmic reticulum (ER) stress. Mid-gestational death was also associated with impairment of oxidative stress defense—a phenotype highly similar to the previously characterized knockout of the Smyd1-interacting transcription factor, skNAC. We describe a potential feedback mechanism in which the stress response factor Tribbles3/TRB3, when directly methylated by Smyd1, acts as a co-repressor of Smyd1-mediated transcription. Our findings suggest that Smyd1 is required for maintaining cardiomyocyte proliferation at minimally two different embryonic heart developmental stages, and its loss leads to linked stress responses that signal ensuing lethality. PMID:25803368

The behavioural effects of predator-induced stress responses in the cricket (Gryllus texensis): the upside of the stress response.

PubMed

Adamo, Shelley A; Kovalko, Ilya; Mosher, Brianna

2013-12-15

Predator-induced stress responses are thought to reduce an animal's risk of being eaten. Therefore, these stress responses should enhance anti-predator behaviour. We found that individual insects (the cricket Gryllus texensis) show reliable behavioural responses (i.e. behavioural types) in a plus-shaped maze. An individual's behaviour in the plus maze remained consistent for at least 1/2 of its adult life. However, after exposure to a model predator, both male and female crickets showed a reduced period of immobility and an increased amount of time spent under shelter compared with controls. These changes could be mimicked by injections of the insect stress neurohormone octopamine. These behavioural changes probably aid crickets in evading predators. Exposure to a model predator increased the ability of crickets to escape a live predator (a bearded dragon, Pogona vitticeps). An injection of octopamine had the same effect, showing that stress hormones can reduce predation. Using crickets to study the fitness consequences of predator-induced stress responses will help integrate ecological and biomedical concepts of 'stress'.

Emerging role of amyloid beta in stress response: Implication for depression and diabetes.

PubMed

Morgese, Maria Grazia; Schiavone, Stefania; Trabace, Luigia

2017-12-15

Chronic stress is considered a widely accepted risk factor for the development of neuropsychiatric and neurological disorders. Indeed, high cortisol levels, and, thus, hypothalamic pituitary adrenal (HPA)-axis dysregulation, have been indicated as the most frequent alteration in patients affected by depression, as well as by Alzheimer's disease (AD). Furthermore, depressive state has been pointed as an early manifestation of AD, advocating an overlap between these neuropathological events. We have previously demonstrated that central soluble beta amyloid 1-42 (Aβ) administration peptide induces a depressive like-behavior in rats, with altered HPA axis activation, reduced cortical serotonin and neurotrophin levels. The crucial role of Aβ in stress response is becoming more and more evident, indeed many reports indicate that its release is increased in stressful conditions and stress-based paradigm. Furthermore, it has been reported that stress controls Aβ production and/or clearance. Chronic stress is responsible of inducing neuroinflammation processes and reduced serotoninergic tone, both pathophysiological mechanisms proposed in the association of depression with another chronic disease, such as diabetes. Likewise, AD has also been indicated as type 3 diabetes, considering the large body of literature that suggests common biological bases. Thus, the main aim of the present review is to evaluate the most recent literature findings in humans and animal models in regard to the role of Aβ in stress response and in relation to the biological substrates and pathological pathways common to AD and comorbid diseases, such as depression and diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

Energetic stress: The reciprocal relationship between energy availability and the stress response.

PubMed

Harrell, C S; Gillespie, C F; Neigh, G N

2016-11-01

The worldwide epidemic of metabolic syndromes and the recognized burden of mental health disorders have driven increased research into the relationship between the two. A maladaptive stress response is implicated in both mental health disorders and metabolic disorders, implicating the hypothalamic-pituitary-adrenal (HPA) axis as a key mediator of this relationship. This review explores how an altered energetic state, such as hyper- or hypoglycemia, as may be manifested in obesity or diabetes, affects the stress response and the HPA axis in particular. We propose that changes in energetic state or energetic demands can result in "energetic stress" that can, if prolonged, lead to a dysfunctional stress response. In this review, we summarize the role of the hypothalamus in modulating energy homeostasis and then briefly discuss the relationship between metabolism and stress-induced activation of the HPA axis. Next, we examine seven mechanisms whereby energetic stress interacts with neuroendocrine stress response systems, including by glucocorticoid signaling both within and beyond the HPA axis; by nutrient-induced changes in glucocorticoid signaling; by impacting the sympathetic nervous system; through changes in other neuroendocrine factors; by inducing inflammatory changes; and by altering the gut-brain axis. Recognizing these effects of energetic stress can drive novel therapies and prevention strategies for mental health disorders, including dietary intervention, probiotics, and even fecal transplant. Copyright © 2015 Elsevier Inc. All rights reserved.

Plant hormone-mediated regulation of stress responses.

PubMed

Verma, Vivek; Ravindran, Pratibha; Kumar, Prakash P

2016-04-14

Being sessile organisms, plants are often exposed to a wide array of abiotic and biotic stresses. Abiotic stress conditions include drought, heat, cold and salinity, whereas biotic stress arises mainly from bacteria, fungi, viruses, nematodes and insects. To adapt to such adverse situations, plants have evolved well-developed mechanisms that help to perceive the stress signal and enable optimal growth response. Phytohormones play critical roles in helping the plants to adapt to adverse environmental conditions. The elaborate hormone signaling networks and their ability to crosstalk make them ideal candidates for mediating defense responses. Recent research findings have helped to clarify the elaborate signaling networks and the sophisticated crosstalk occurring among the different hormone signaling pathways. In this review, we summarize the roles of the major plant hormones in regulating abiotic and biotic stress responses with special focus on the significance of crosstalk between different hormones in generating a sophisticated and efficient stress response. We divided the discussion into the roles of ABA, salicylic acid, jasmonates and ethylene separately at the start of the review. Subsequently, we have discussed the crosstalk among them, followed by crosstalk with growth promoting hormones (gibberellins, auxins and cytokinins). These have been illustrated with examples drawn from selected abiotic and biotic stress responses. The discussion on seed dormancy and germination serves to illustrate the fine balance that can be enforced by the two key hormones ABA and GA in regulating plant responses to environmental signals. The intricate web of crosstalk among the often redundant multitudes of signaling intermediates is just beginning to be understood. Future research employing genome-scale systems biology approaches to solve problems of such magnitude will undoubtedly lead to a better understanding of plant development. Therefore, discovering additional crosstalk

Satisfaction with the initial police response and development of posttraumatic stress disorder symptoms in victims of domestic burglary.

PubMed

Kunst, M J J; Rutten, S; Knijf, E

2013-02-01

The current study used a prospective design to investigate the association between early symptoms, satisfaction with the initial police response, and development of posttraumatic stress disorder (PTSD) symptomatology in victims of domestic burglary (n = 95). Early symptoms and satisfaction with the initial police response were assessed through telephone interviews conducted within the first month after the burglary and PTSD symptoms 4 to 6 weeks after baseline. Separate regression models were tested for satisfaction with performance and satisfaction with procedure. Results suggested that early symptoms were a risk factor for PTSD symptomatology (β = .50, p < .001 and β = .48, p < .001) above and beyond levels of peritraumatic distress (β = .21, p < .05 and β = .22, p < .05) and irrespective of level of satisfaction (β = -.02, ns and β = -.10, ns). Victims with high levels of early symptoms, however, were clearly at an increased risk of PTSD symptomatology if they scored low on satisfaction at baseline. Results were discussed in light of the framework of therapeutic jurisprudence. Copyright © 2013 International Society for Traumatic Stress Studies.

Maternal regulation of the infant's HPA axis stress response: Seymour 'Gig' Levine's legacy to Neuroendocrinology.

PubMed

Suchecki, Deborah

2018-05-18

Thirty years ago, Seymour 'Gig' Levine published a serendipitous, yet, seminal finding on the regulatory role of maternal presence on the corticosterone stress response of neonatal rats, during the developmental period know as stress hyporesponsive period. At the same time, his group of students also studied the stress response of infant monkeys to maternal separation, as a means to understand the stressful nature of disruptions of attachment to the primary caregiver. Gig and his group of students and collaborators, mainly in the USA and the Netherlands, investigated how initial social relationships buffer the stress response of non-human primate and rodent infants. His work in rodents revolved on determining how prolonged deprivation of maternal care disinhibits the stress response of neonates and how maternal behaviours regulate specific aspects of the hypothalamic-pituitary-adrenal axis. The 24 h maternal deprivation was useful to determine the importance of nutrition to suppress the corticosterone stress response, whilst anogenital licking and grooming inhibited stress-induced ACTH release and the combination of both behaviours prevented the effects of maternal deprivation on the central hypothalamic stress response. Levine's group also studied the consequences of maternal deprivation on basal and stress-induced activity of the HPA axis in juveniles' and the persistent effects of replacement of maternal behaviours on these parameters. Gig's legacy allowed many groups around the world to use the 24 h maternal deprivation paradigm as an animal model of vulnerability and resilience to stress-related psychiatric disorders and to study the neurobiological underpinnings of disruption of the mother-infant relationship and loss of parental care, a highly prevalent condition in humans. This review pays homage to a great scientist and mentor, whose discoveries paved the way for the understanding of how early social relations build resilience or lead to susceptibility to

Cortisol modulates men's affiliative responses to acute social stress.

PubMed

Berger, Justus; Heinrichs, Markus; von Dawans, Bernadette; Way, Baldwin M; Chen, Frances S

2016-01-01

The dominant characterization of the physiological and behavioral human stress reaction is the fight-or-flight response. On the other hand, it has been suggested that social affiliation during stressful times ("tend-and-befriend") also represents a common adaptive response to stress, particularly for women. In the current study, we investigate the extent to which men may also show affiliative responses following acute stress. In addition, we examine a potential neuroendocrine modulator of the hypothesized affiliative response. Eighty male students (forty dyads) were recruited to undergo either the Trier Social Stress Test for Groups (TSST-G) or a non-stressful control situation. Subsequently, participants completed a dyadic interaction task and were then asked to report their feelings of psychological closeness to their interaction partner. Although participants assigned to the stress condition did not differ overall on psychological closeness from participants assigned to the control condition, participants with high cortisol responses to the stressor showed significantly higher ratings of psychological closeness to their interaction partner than participants with low cortisol responses. Our findings suggest that men may form closer temporary bonds following stressful situations that are accompanied by a significant cortisol response. We suggest that the traditional characterization of the male stress response in terms of "fight-or-flight" may be incomplete, and that social affiliation may in fact represent a common, adaptive response to stress in men. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microarray and growth analyses identify differences and similarities of early corn response to weeds, shade, and nitrogen stress

USDA-ARS?s Scientific Manuscript database

Weed interference with crop growth is often attributed to water, nutrient, or light competition; however, specific physiological responses to these stresses are not well described. This study’s objective was to compare growth, yield, and gene expression responses of corn to nitrogen (N), low light (...

Transcriptome Analysis of Early Responsive Genes in Rice during Magnaporthe oryzae Infection.

PubMed

Wang, Yiming; Kwon, Soon Jae; Wu, Jingni; Choi, Jaeyoung; Lee, Yong-Hwan; Agrawal, Ganesh Kumar; Tamogami, Shigeru; Rakwal, Randeep; Park, Sang-Ryeol; Kim, Beom-Gi; Jung, Ki-Hong; Kang, Kyu Young; Kim, Sang Gon; Kim, Sun Tae

2014-12-01

Rice blast disease caused by Magnaporthe oryzae is one of the most serious diseases of cultivated rice (Oryza sativa L.) in most rice-growing regions of the world. In order to investigate early response genes in rice, we utilized the transcriptome analysis approach using a 300 K tilling microarray to rice leaves infected with compatible and incompatible M. oryzae strains. Prior to the microarray experiment, total RNA was validated by measuring the differential expression of rice defense-related marker genes (chitinase 2, barwin, PBZ1, and PR-10) by RT-PCR, and phytoalexins (sakuranetin and momilactone A) with HPLC. Microarray analysis revealed that 231 genes were up-regulated (>2 fold change, p < 0.05) in the incompatible interaction compared to the compatible one. Highly expressed genes were functionally characterized into metabolic processes and oxidation-reduction categories. The oxidative stress response was induced in both early and later infection stages. Biotic stress overview from MapMan analysis revealed that the phytohormone ethylene as well as signaling molecules jasmonic acid and salicylic acid is important for defense gene regulation. WRKY and Myb transcription factors were also involved in signal transduction processes. Additionally, receptor-like kinases were more likely associated with the defense response, and their expression patterns were validated by RT-PCR. Our results suggest that candidate genes, including receptor-like protein kinases, may play a key role in disease resistance against M. oryzae attack.

Development of the cortisol circadian rhythm in the light of stress early in life.

PubMed

Simons, Sterre S H; Beijers, Roseriet; Cillessen, Antonius H N; de Weerth, Carolina

2015-12-01

The secretion of the stress hormone cortisol follows a diurnal circadian rhythm. There are indications that this rhythm is affected by stress early in life. This paper addresses the development of the cortisol circadian rhythm between 1 and 6 years of age, and the role of maternal stress and anxiety early in the child's life on this (developing) rhythm. Participants were 193 healthy mother-child dyads from a community sample. Self-reported maternal stress and anxiety and physiological stress (saliva cortisol), were assessed prenatally (gestational week 37). Postnatally, self-reported maternal stress and anxiety were measured at 3, 6, 12, 30, and 72 months. Saliva cortisol samples from the children were collected on two days (four times each day) at 12, 30, and 72 months of age. The total amount of cortisol during the day and the cortisol decline over the day were determined to indicate children's cortisol circadian rhythm. Multilevel analyses showed that the total amount of cortisol decreased between 1 and 6 years. Furthermore, more maternal pregnancy-specific stress was related to higher total amounts of cortisol in the child. Higher levels of early postnatal maternal anxiety were associated with flatter cortisol declines in children. Higher levels of early postnatal maternal daily hassles were associated with steeper child cortisol declines over the day. These results indicated developmental change in children's cortisol secretion from 1 to 6 years and associations between maternal stress and anxiety early in children's lives and children's cortisol circadian rhythm in early childhood. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biological stress response terminology: Integrating the concepts of adaptive response and preconditioning stress within a hormetic dose-response framework.

PubMed

Calabrese, Edward J; Bachmann, Kenneth A; Bailer, A John; Bolger, P Michael; Borak, Jonathan; Cai, Lu; Cedergreen, Nina; Cherian, M George; Chiueh, Chuang C; Clarkson, Thomas W; Cook, Ralph R; Diamond, David M; Doolittle, David J; Dorato, Michael A; Duke, Stephen O; Feinendegen, Ludwig; Gardner, Donald E; Hart, Ronald W; Hastings, Kenneth L; Hayes, A Wallace; Hoffmann, George R; Ives, John A; Jaworowski, Zbigniew; Johnson, Thomas E; Jonas, Wayne B; Kaminski, Norbert E; Keller, John G; Klaunig, James E; Knudsen, Thomas B; Kozumbo, Walter J; Lettieri, Teresa; Liu, Shu-Zheng; Maisseu, Andre; Maynard, Kenneth I; Masoro, Edward J; McClellan, Roger O; Mehendale, Harihara M; Mothersill, Carmel; Newlin, David B; Nigg, Herbert N; Oehme, Frederick W; Phalen, Robert F; Philbert, Martin A; Rattan, Suresh I S; Riviere, Jim E; Rodricks, Joseph; Sapolsky, Robert M; Scott, Bobby R; Seymour, Colin; Sinclair, David A; Smith-Sonneborn, Joan; Snow, Elizabeth T; Spear, Linda; Stevenson, Donald E; Thomas, Yolene; Tubiana, Maurice; Williams, Gary M; Mattson, Mark P

2007-07-01

Many biological subdisciplines that regularly assess dose-response relationships have identified an evolutionarily conserved process in which a low dose of a stressful stimulus activates an adaptive response that increases the resistance of the cell or organism to a moderate to severe level of stress. Due to a lack of frequent interaction among scientists in these many areas, there has emerged a broad range of terms that describe such dose-response relationships. This situation has become problematic because the different terms describe a family of similar biological responses (e.g., adaptive response, preconditioning, hormesis), adversely affecting interdisciplinary communication, and possibly even obscuring generalizable features and central biological concepts. With support from scientists in a broad range of disciplines, this article offers a set of recommendations we believe can achieve greater conceptual harmony in dose-response terminology, as well as better understanding and communication across the broad spectrum of biological disciplines.

Early life social stress induced changes in depression and anxiety associated neural pathways which are correlated with impaired maternal care.

PubMed

Murgatroyd, Christopher A; Peña, Catherine J; Podda, Giovanni; Nestler, Eric J; Nephew, Benjamin C

2015-08-01

Exposures to various types of early life stress can be robust predictors of the development of psychiatric disorders, including depression and anxiety. The objective of the current study was to investigate the roles of the translationally relevant targets of central vasopressin, oxytocin, ghrelin, orexin, glucocorticoid, and the brain-derived neurotrophic factor (BDNF) pathway in an early chronic social stress (ECSS) based rodent model of postpartum depression and anxiety. The present study reports novel changes in gene expression and extracellular signal related kinase (ERK) protein levels in the brains of ECSS exposed rat dams that display previously reported depressed maternal care and increased maternal anxiety. Decreases in oxytocin, orexin, and ERK proteins, increases in ghrelin receptor, glucocorticoid and mineralocorticoid receptor mRNA levels, and bidirectional changes in vasopressin underscore related work on the adverse long-term effects of early life stress on neural activity and plasticity, maternal behavior, responses to stress, and depression and anxiety-related behavior. The differences in gene and protein expression and robust correlations between expression and maternal care and anxiety support increased focus on these targets in animal and clinical studies of the adverse effects of early life stress, especially those focusing on depression and anxiety in mothers and the transgenerational effects of these disorders on offspring. Copyright © 2015 Elsevier B.V. All rights reserved.

Response of Desulfovibrio vulgaris to Alkaline Stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stolyar, S.; He, Q.; He, Z.

2007-11-30

The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included threemore » ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).« less

Job Stress and Coping Strategies among Early Childhood Teachers in Central Taiwan

ERIC Educational Resources Information Center

Hung, Chih-Lun

2012-01-01

The purpose of this study was to explore the association between job stress and coping strategies in early childhood teachers in Central Taiwan. A quantitative approach was utilized, and data were collected from 314 participants. The results of the present study suggest that (1) early childhood teachers believed that their job stress was due to a…

Early life stress impairs social recognition due to a blunted response of vasopressin release within the septum of adult male rats.

PubMed

Lukas, Michael; Bredewold, Remco; Landgraf, Rainer; Neumann, Inga D; Veenema, Alexa H

2011-07-01

Early life stress poses a risk for the development of psychopathologies characterized by disturbed emotional, social, and cognitive performance. We used maternal separation (MS, 3h daily, postnatal days 1-14) to test whether early life stress impairs social recognition performance in juvenile (5-week-old) and adult (16-week-old) male Wistar rats. Social recognition was tested in the social discrimination test and defined by increased investigation by the experimental rat towards a novel rat compared with a previously encountered rat. Juvenile control and MS rats demonstrated successful social recognition at inter-exposure intervals of 30 and 60 min. However, unlike adult control rats, adult MS rats failed to discriminate between a previously encountered and a novel rat after 60 min. The social recognition impairment of adult MS rats was accompanied by a lack of a rise in arginine vasopressin (AVP) release within the lateral septum seen during social memory acquisition in adult control rats. This blunted response of septal AVP release was social stimulus-specific because forced swimming induced a rise in septal AVP release in both control and MS rats. Retrodialysis of AVP (1 μg/ml, 3.3 μl/min, 30 min) into the lateral septum during social memory acquisition restored social recognition in adult MS rats at the 60-min interval. These studies demonstrate that MS impairs social recognition performance in adult rats, which is likely caused by blunted septal AVP activation. Impaired social recognition may be linked to MS-induced changes in other social behaviors like aggression as shown previously. Copyright © 2010 Elsevier Ltd. All rights reserved.

Differentially delayed root proteome responses to salt stress in sugar cane varieties.

PubMed

Pacheco, Cinthya Mirella; Pestana-Calsa, Maria Clara; Gozzo, Fabio Cesar; Mansur Custodio Nogueira, Rejane Jurema; Menossi, Marcelo; Calsa, Tercilio

2013-12-06

Soil salinity is a limiting factor to sugar cane crop development, although in general plants present variable mechanisms of tolerance to salinity stress. The molecular basis underlying these mechanisms can be inferred by using proteomic analysis. Thus, the objective of this work was to identify differentially expressed proteins in sugar cane plants submitted to salinity stress. For that, a greenhouse experiment was established with four sugar cane varieties and two salt conditions, 0 mM (control) and 200 mM NaCl. Physiological and proteomics analyses were performed after 2 and 72 h of stress induction by salt. Distinct physiological responses to salinity stress were observed in the varieties and linked to tolerance mechanisms. In proteomic analysis, the roots soluble protein fraction was extracted, quantified, and analyzed through bidimensional electrophoresis. Gel images analyses were done computationally, where in each contrast only one variable was considered (salinity condition or variety). Differential spots were excised, digested by trypsin, and identified via mass spectrometry. The tolerant variety RB867515 showed the highest accumulation of proteins involved in growth, development, carbohydrate and energy metabolism, reactive oxygen species metabolization, protein protection, and membrane stabilization after 2 h of stress. On the other hand, the presence of these proteins in the sensitive variety was verified only in stress treatment after 72 h. These data indicate that these stress responses pathways play a role in the tolerance to salinity in sugar cane, and their effectiveness for phenotypical tolerance depends on early stress detection and activation of the coding genes expression.

The endoplasmic reticulum stress response: A link with tuberculosis?

PubMed

Cui, Yongyong; Zhao, Deming; Barrow, Paul Andrew; Zhou, Xiangmei

2016-03-01

Tuberculosis (TB) remains a major cause of mortality and morbidity in the worldwide. The endoplasmic-reticulum stress (ERS) response constitutes a cellular process that is triggered by mycobacterial infection that disturbs the folding of proteins in the endoplasmic reticulum (ER). The unfolded protein response (UPR) is induced to suspend the synthesis of early proteins and reduce the accumulation of unfolded- or misfolded proteins in the ER restoring normal physiological cell function. Prolonged or uncontrolled ERS leads to the activation of three signaling pathways (IRE1, PERK and ATF6) which directs the cell towards apoptosis. The absence of this process facilitates spread of the mycobacteria within the body. We summarize here recent advances in understanding the signaling pathway diversity governing ERS in relation to TB. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Serotonin Transporter and Early Life Stress: Translational Perspectives

PubMed Central

Houwing, Danielle J.; Buwalda, Bauke; van der Zee, Eddy A.; de Boer, Sietse F.; Olivier, Jocelien D. A.

2017-01-01

The interaction between the serotonin transporter (SERT) linked polymorphic region (5-HTTLPR) and adverse early life stressing (ELS) events is associated with enhanced stress susceptibility and risk to develop mental disorders like major depression, anxiety, and aggressiveness. In particular, human short allele carriers are at increased risk. This 5-HTTLPR polymorphism is absent in the rodent SERT gene, but heterozygous SERT knockout rodents (SERT+/−) show several similarities to the human S-allele carrier, therefore creating an animal model of the human situation. Many rodent studies investigated ELS interactions in SERT knockout rodents combined with ELS. However, underlying neuromolecular mechanisms of the (mal)adaptive responses to adversity displayed by SERT rodents remain to be elucidated. Here, we provide a comprehensive review including studies describing mechanisms underlying SERT variation × ELS interactions in rodents. Alterations at the level of translation and transcription but also epigenetic alterations considerably contribute to underlying mechanisms of SERT variation × ELS interactions. In particular, SERT+/− rodents exposed to adverse early rearing environment may be of high translational and predictive value to the more stress sensitive human short-allele carrier, considering the similarity in neurochemical alterations. Therefore, SERT+/− rodents are highly relevant in research that aims to unravel the complex psychopathology of mental disorders. So far, most studies fail to show solid evidence for increased vulnerability to develop affective-like behavior after ELS in SERT+/− rodents. Several reasons may underlie these failures, e.g., (1) stressors used might not be optimal or severe enough to induce maladaptations, (2) effects in females are not sufficiently studied, and (3) few studies include both behavioral manifestations and molecular correlates of ELS-induced effects in SERT+/− rodents. Of course, one should not exclude the

Early life social stress and resting state functional connectivity in postpartum rat anterior cingulate circuits.

PubMed

Nephew, Benjamin C; Febo, Marcelo; Huang, Wei; Colon-Perez, Luis M; Payne, Laurellee; Poirier, Guillaume L; Greene, Owen; King, Jean A

2018-03-15

Continued development and refinement of resting state functional connectivity (RSFC) fMRI techniques in both animal and clinical studies has enhanced our comprehension of the adverse effects of stress on psychiatric health. The objective of the current study was to assess both maternal behavior and resting state functional connectivity (RSFC) changes in these animals when they were dams caring for their own young. It was hypothesized that ECSS exposed dams would express depressed maternal care and exhibit similar (same networks), yet different specific changes in RSFC (different individual nuclei) than reported when they were adult females. We have developed an ethologically relevant transgenerational model of the role of chronic social stress (CSS) in the etiology of postpartum depression and anxiety. Initial fMRI investigation of the CSS model indicates that early life exposure to CSS (ECSS) induces long term changes in functional connectivity in adult nulliparous female F1 offspring. ECSS in F1 dams resulted in depressed maternal care specifically during early lactation, consistent with previous CSS studies, and induced changes in functional connectivity in regions associated with sensory processing, maternal and emotional responsiveness, memory, and the reward pathway, with robust changes in anterior cingulate circuits. The sample sizes for the fMRI groups were low, limiting statistical power. This behavioral and functional neuroanatomical foundation can now be used to enhance our understanding of the neural etiology of early life stress associated disorders and test preventative measures and treatments for stress related disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

Transcriptome profiling of low temperature-treated cassava apical shoots showed dynamic responses of tropical plant to cold stress

PubMed Central

2012-01-01

Background Cassava is an important tropical root crop adapted to a wide range of environmental stimuli such as drought and acid soils. Nevertheless, it is an extremely cold-sensitive tropical species. Thus far, there is limited information about gene regulation and signalling pathways related to the cold stress response in cassava. The development of microarray technology has accelerated the study of global transcription profiling under certain conditions. Results A 60-mer oligonucleotide microarray representing 20,840 genes was used to perform transcriptome profiling in apical shoots of cassava subjected to cold at 7°C for 0, 4 and 9 h. A total of 508 transcripts were identified as early cold-responsive genes in which 319 sequences had functional descriptions when aligned with Arabidopsis proteins. Gene ontology annotation analysis identified many cold-relevant categories, including 'Response to abiotic and biotic stimulus', 'Response to stress', 'Transcription factor activity', and 'Chloroplast'. Various stress-associated genes with a wide range of biological functions were found, such as signal transduction components (e.g., MAP kinase 4), transcription factors (TFs, e.g., RAP2.11), and reactive oxygen species (ROS) scavenging enzymes (e.g., catalase 2), as well as photosynthesis-related genes (e.g., PsaL). Seventeen major TF families including many well-studied members (e.g., AP2-EREBP) were also involved in the early response to cold stress. Meanwhile, KEGG pathway analysis uncovered many important pathways, such as 'Plant hormone signal transduction' and 'Starch and sucrose metabolism'. Furthermore, the expression changes of 32 genes under cold and other abiotic stress conditions were validated by real-time RT-PCR. Importantly, most of the tested stress-responsive genes were primarily expressed in mature leaves, stem cambia, and fibrous roots rather than apical buds and young leaves. As a response to cold stress in cassava, an increase in transcripts and

Development of the embryonic heat shock response and the impact of repeated thermal stress in early stage lake whitefish (Coregonus clupeaformis) embryos.

PubMed

Whitehouse, Lindy M; McDougall, Chance S; Stefanovic, Daniel I; Boreham, Douglas R; Somers, Christopher M; Wilson, Joanna Y; Manzon, Richard G

2017-10-01

Lake whitefish (Coregonus clupeaformis) embryos were exposed to thermal stress (TS) at different developmental stages to determine when the heat shock response (HSR) can be initiated and if it is altered by exposure to repeated TS. First, embryos were subject to one of three different TS temperatures (6, 9, or 12°C above control) at 4 points in development (21, 38, 60 and 70 days post-fertilisation (dpf)) for 2h followed by a 2h recovery to understand the ontogeny of the HSR. A second experiment explored the effects of repeated TS on the HSR in embryos from 15 to 75 dpf. Embryos were subjected to one of two TS regimes; +6°C TS for 1h every 6 days or +9°C TS for 1h every 6 days. Following a 2h recovery, a subset of embryos was sampled. Our results show that embryos could initiate a HSR via upregulation of heat shock protein 70 (hsp70) mRNA at all developmental ages studied, but that this response varied with age and was only observed with a TS of +9 or +12°C. In comparison, when embryos received multiple TS treatments, hsp70 was not induced in response to the 1h TS and 2h recovery, and a downregulation was observed at 39 dpf. Downregulation of hsp47 and hsp90α mRNA was also observed in early age embryos. Collectively, these data suggest that embryos are capable of initiating a HSR at early age and throughout embryogenesis, but that repeated TS can alter the HSR, and may result in either reduced responsiveness or a downregulation of inducible hsps. Our findings warrant further investigation into both the short- and long-term effects of repeated TS on lake whitefish development. Copyright © 2017 Elsevier Ltd. All rights reserved.

West nile virus infections suppress early viral RNA synthesis and avoid inducing the cell stress granule response.

PubMed

Courtney, S C; Scherbik, S V; Stockman, B M; Brinton, M A

2012-04-01

West Nile virus (WNV) recently became endemic in the United States and is a significant cause of human morbidity and mortality. Natural WNV strain infections do not induce stress granules (SGs), while W956IC (a lineage 2/1 chimeric WNV infectious clone) virus infections produce high levels of early viral RNA and efficiently induce SGs through protein kinase R (PKR) activation. Additional WNV chimeric viruses made by replacing one or more W956IC genes with the lineage 1 Eg101 equivalent in the W956IC backbone were analyzed. The Eg-NS4b+5, Eg-NS1+3+4a, and Eg-NS1+4b+5 chimeras produced low levels of viral RNA at early times of infection and inefficiently induced SGs, suggesting the possibility that interactions between viral nonstructural proteins and/or between viral nonstructural proteins and cell proteins are involved in suppressing early viral RNA synthesis and membrane remodeling during natural WNV strain infections. Detection of exposed viral double-stranded RNA (dsRNA) in W956IC-infected cells suggested that the enhanced early viral RNA synthesis surpassed the available virus-induced membrane protection and allowed viral dsRNA to activate PKR.

Stress response physiology of thermophiles.

PubMed

Ranawat, Preeti; Rawat, Seema

2017-04-01

Thermo (or hyperthermo) philic microorganisms are ubiquitous having a wide range of habitats from freshly fallen snow to pasteurized milk to geothermal areas like hot springs. The variations in physicochemical conditions, viz., temperature, pH, nutrient availability and light intensity in the habitats always pose stress conditions for the inhabitants leading to slow growth or cell death. The industrial processes used for harvesting secondary metabolites such as enzymes, toxins and organic acids also create stressed environments for thermophiles. The production of DNA-binding proteins, activation of reactive oxygen species detoxification system, compatible solute accumulation, expression of heat shock proteins and alterations in morphology are a few examples of physiological changes demonstrated by these microscopic lifeforms in stress. These microorganisms exhibit complex genetic and physiological changes to minimize, adapt to and repair damage caused by extreme environmental disturbances. These changes are termed as 'stress responses' which enable them to stabilize their homeostasis. The exploration of important thermophilic factors would pave the way in engineering the microbial strains for various biotechnological applications. This review article presents a picture of physiological responses of thermophiles against various stress conditions as their mechanisms to respond to stress make them model organisms to further explore them for basic and applied biology purposes.

Hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes: sex differences in regulation of stress responsivity.

PubMed

Oyola, Mario G; Handa, Robert J

2017-09-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism's response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic-pituitary-gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life.

Hypothalamic–pituitary–adrenal and hypothalamic–pituitary–gonadal axes: sex differences in regulation of stress responsivity

PubMed Central

Oyola, Mario G.; Handa, Robert J.

2018-01-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic–pituitary–adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism’s response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic–pituitary–gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life. PMID:28859530

Shared and unique responses of plants to multiple individual stresses and stress combinations: physiological and molecular mechanisms

PubMed Central

Pandey, Prachi; Ramegowda, Venkategowda; Senthil-Kumar, Muthappa

2015-01-01

In field conditions, plants are often simultaneously exposed to multiple biotic and abiotic stresses resulting in substantial yield loss. Plants have evolved various physiological and molecular adaptations to protect themselves under stress combinations. Emerging evidences suggest that plant responses to a combination of stresses are unique from individual stress responses. In addition, plants exhibit shared responses which are common to individual stresses and stress combination. In this review, we provide an update on the current understanding of both unique and shared responses. Specific focus of this review is on heat–drought stress as a major abiotic stress combination and, drought–pathogen and heat–pathogen as examples of abiotic–biotic stress combinations. We also comprehend the current understanding of molecular mechanisms of cross talk in relation to shared and unique molecular responses for plant survival under stress combinations. Thus, the knowledge of shared responses of plants from individual stress studies and stress combinations can be utilized to develop varieties with broad spectrum stress tolerance. PMID:26442037

Early Life Stress Differentially Modulates Distinct Forms of Brain Plasticity in Young and Adult Mice

PubMed Central

Reichardt, Wilfried; Clark, Kristin; Geiger, Julia; Gross, Claus M.; Heyer, Andrea; Neagu, Valentin; Bhatia, Harsharan; Atas, Hasan C.; Fiebich, Bernd L.; Bischofberger, Josef; Haas, Carola A.; Normann, Claus

2012-01-01

Background Early life trauma is an important risk factor for many psychiatric and somatic disorders in adulthood. As a growing body of evidence suggests that brain plasticity is disturbed in affective disorders, we examined the short-term and remote effects of early life stress on different forms of brain plasticity. Methodology/Principal Findings Mice were subjected to early deprivation by individually separating pups from their dam in the first two weeks after birth. Distinct forms of brain plasticity were assessed in the hippocampus by longitudinal MR volumetry, immunohistochemistry of neurogenesis, and whole-cell patch-clamp measurements of synaptic plasticity. Depression-related behavior was assessed by the forced swimming test in adult animals. Neuropeptides and their receptors were determined by real-time PCR and immunoassay. Early maternal deprivation caused a loss of hippocampal volume, which returned to normal in adulthood. Adult neurogenesis was unaffected by early life stress. Long-term synaptic potentiation, however, was normal immediately after the end of the stress protocol but was impaired in adult animals. In the forced swimming test, adult animals that had been subjected to early life stress showed increased immobility time. Levels of substance P were increased both in young and adult animals after early deprivation. Conclusion Hippocampal volume was affected by early life stress but recovered in adulthood which corresponded to normal adult neurogenesis. Synaptic plasticity, however, exhibited a delayed impairment. The modulation of synaptic plasticity by early life stress might contribute to affective dysfunction in adulthood. PMID:23071534

Mothers of children with developmental disabilities: stress in early and middle childhood.

PubMed

Azad, Gazi; Blacher, Jan; Marcoulides, George A

2013-10-01

Using a sample of 219 families of children with (n=94) and without (n=125) developmental disabilities, this study examined the longitudinal perspectives of maternal stress in early (ages 3-5) and middle childhood (ages 6-13) and its relationship to mothers' and children's characteristics. Multivariate latent curve models indicated that maternal stress remained high and stable with minimal individual variation in early childhood, but declined with significant individual variation in middle childhood. Maternal stress at the beginning of middle childhood was associated with earlier maternal stress, as well as children's behavioral problems and social skills. The trajectory of maternal stress across middle childhood was related to children's behavioral problems. Implications for interventions are discussed. Copyright © 2013. Published by Elsevier Ltd.

When Does Stress Help or Harm? The Effects of Stress Controllability and Subjective Stress Response on Stroop Performance

PubMed Central

Henderson, Roselinde K.; Snyder, Hannah R.; Gupta, Tina; Banich, Marie T.

2012-01-01

The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest

When does stress help or harm? The effects of stress controllability and subjective stress response on stroop performance.

PubMed

Henderson, Roselinde K; Snyder, Hannah R; Gupta, Tina; Banich, Marie T

2012-01-01

The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual's response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop

Response inhibition and cognitive appraisal in clients with acute stress disorder and posttraumatic stress disorder.

PubMed

Abolghasemi, Abass; Bakhshian, Fereshteh; Narimani, Mohammad

2013-08-01

The purpose of the present study was to compare response inhibition and cognitive appraisal in clients with acute stress disorder, clients with posttraumatic stress disorder, and normal individuals. This was a comparative study. The sample consisted of 40 clients with acute stress disorder, 40 patients with posttraumatic stress disorder, and 40 normal individuals from Mazandaran province selected through convenience sampling method. Data were collected using Composite International Diagnostic Interview, Stroop Color-Word Test, Posttraumatic Cognitions Inventory, and the Impact of Event Scale. Results showed that individuals with acute stress disorder are less able to inhibit inappropriate responses and have more impaired cognitive appraisals compared to those with posttraumatic stress disorder. Moreover, results showed that response inhibition and cognitive appraisal explain 75% of the variance in posttraumatic stress disorder symptoms and 38% of the variance in posttraumatic stress disorder symptoms. The findings suggest that response inhibition and cognitive appraisal are two variables that influence the severity of posttraumatic stress disorder and acute stress disorder symptoms. Also, these results have important implications for pathology, prevention, and treatment of posttraumatic stress disorder and acute stress disorder.

Impacts of Early Life Stress on the Methylome and Transcriptome of Atlantic Salmon.

PubMed

Moghadam, Hooman K; Johnsen, Hanne; Robinson, Nicholas; Andersen, Øivind; H Jørgensen, Even; Johnsen, Helge K; Bæhr, Vegar J; Tveiten, Helge

2017-07-10

Exposure to environmental stressors during early-life stages can change the rate and timing of various developmental processes. Epigenetic marks affecting transcriptional regulation can be altered by such environmental stimuli. To assess how stress might affect the methylome and transcriptome in salmon, fish were treated using cold-shock and air-exposure from the eye-stage until start-feeding. The fish were either stressed prior to hatching (E), post-hatching (PH), pre- and post-hatching (EPH) or not stressed (CO). Assessing transcriptional abundances just prior to start feeding, E and PH individuals were found to have modified the expression of thousands of genes, many with important functions in developmental processes. The EPH individuals however, showed expression similar to those of CO, suggesting an adaptive response to extended periods of stress. The methylome of stressed individuals differed from that of the CO, suggesting the importance of environment in shaping methylation signatures. Through integration of methylation with transcription, we identified bases with potential regulatory functions, some 10s of kb away from the targeted genes. We then followed fish growth for an additional year. Individuals in EPH showed superior growth compared to other treatment groups, highlighting how stress can potentially have long-lasting effects on an organism's ability to adapt to environmental perturbations.

Waterborne aripiprazole blunts the stress response in zebrafish

NASA Astrophysics Data System (ADS)

Barcellos, Heloísa Helena De Alcantara; Kalichak, Fabiana; da Rosa, João Gabriel Santos; Oliveira, Thiago Acosta; Koakoski, Gessi; Idalencio, Renan; de Abreu, Murilo Sander; Giacomini, Ana Cristina Varrone; Fagundes, Michele; Variani, Cristiane; Rossini, Mainara; Piato, Angelo L.; Barcellos, Leonardo José Gil

2016-11-01

Here we provide, at least to our knowledge, the first evidence that aripiprazole (APPZ) in the water blunts the stress response of exposed fish in a concentration ten times lower than the concentration detected in the environment. Although the mechanism of APPZ in the neuroendocrine axis is not yet determined, our results highlight that the presence of APPZ residues in the environment may interfere with the stress responses in fish. Since an adequate stress response is crucial to restore fish homeostasis after stressors, fish with impaired stress response may have trouble to cope with natural and/or imposed stressors with consequences to their welfare and survival.

Transcriptomic Analysis of the Primary Roots of Alhagi sparsifolia in Response to Water Stress

PubMed Central

Pei, Xinwu; Zhang, Chao; Jia, Shirong; Li, Weimin

2015-01-01

Background Alhagi sparsifolia is a typical desert phreatophyte and has evolved to withstand extreme dry, cold and hot weather. While A. sparsifolia represents an ideal model to study the molecular mechanism of plant adaption to abiotic stress, no research has been done in this aspect to date. Here we took advantage of Illumina platform to survey transcriptome in primary roots of A. sparsifolia under water stress conditions in aim to facilitate the exploration of its genetic basis for drought tolerance. Methodology and Principal Findings We sequenced four primary roots samples individually collected at 0, 6, 24 and 30h from the A. sparsifolia seedlings in the course of 24h of water stress following 6h of rehydration. The resulting 38,763,230, 67,511,150, 49,259,804 and 54,744,906 clean reads were pooled and assembled into 33,255 unigenes with an average length of 1,057 bp. All-unigenes were subjected to functional annotation by searching against the public databases. Based on the established transcriptome database, we further evaluated the gene expression profiles in the four different primary roots samples, and identified numbers of differently expressed genes (DEGs) reflecting the early response to water stress (6h vs. 0h), the late response to water stress (24h vs. 0h) and the response to post water stress rehydration (30h vs. 24h). Moreover, the DEGs specifically regulated at 6, 24 and 30h were captured in order to depict the dynamic changes of gene expression during water stress and subsequent rehydration. Functional categorization of the DEGs indicated the activation of oxidoreductase system, and particularly emphasized the significance of the ‘Glutathione metabolism pathway’ in response to water stress. Conclusions This is the first description of the genetic makeup of A. sparsifolia, thus providing a substantial contribution to the sequence resources for this species. The identified DEGs offer a deep insight into the molecular mechanism of A. sparsifolia

Development of early age shrinkage stresses in reinforced concrete bridge decks

NASA Astrophysics Data System (ADS)

William, Gergis W.; Shoukry, Samir N.; Riad, Mourad Y.

2008-12-01

This paper describes the instrumentation and data analysis of a reinforced concrete bridge deck constructed on 3-span continuous steel girders in Evansville, West Virginia. An instrumentation system consisting of 232 sensors is developed and implemented specifically to measure strains and temperature in concrete deck, strains in longitudinal and transverse rebars, the overall contraction and expansion of concrete deck, and crack openings. Data from all sensors are automatically collected every 30 minutes starting at the time of placing the concrete deck. Measured strain and temperature time-histories were used to calculate the stresses, which were processed to attenuate the thermal effects due to daily temperature changes and isolate the drying shrinkage component. The results indicated that most of concrete shrinkage occurs during the first three days. Under the constraining effects from stay-in-place forms and reinforcement, early age shrinkage leads to elevated longitudinal stress, which is the main factor responsible for crack initiation.

Stress biomarker responses to different protocols of forced exercise in chronically stressed rats.

PubMed

Radahmadi, Maryam; Alaei, Hojjatallah; Sharifi, Mohammad Reza; Hosseini, Nasrin

2017-01-01

Stress is one of the most significant causes of major health problems on a global scale. The beneficial effects of exercise on combating stress, however, are well-established. The present study investigated the stress biomarker responses, such as serum corticosterone, interlukin-1β, and glucose levels, to different (preventive, therapeutic, protective, and continuous) protocols of forced exercise under stress. Male rats were randomly allocated to the following five groups: stressed, preventive, therapeutic, protective, and continuous (and/or pre-stress, post-stress, stress-accompanied, and both pre-stress and stress-accompanied exercise respectively) exercise groups. Stress was applied 6 h/day for 21 days and the treadmill running was employed at a speed of 20-21 m/min for 21 and 42 days. The findings showed that the therapeutic, protective, and continuous exercises led to reduced corticosterone and glucose levels. Whereas, the preventive exercise did not reverse the stress responses, and that the therapeutic exercise led to a significant decline in serum interlukin-1β. It is concluded that protective, therapeutic, and, particularly, continuous exercises lead to significant reductions in serum corticosterone and the associated stress-induced hyperglycemia. Moreover, it appears that the timing and duration of exercise are the two factors contributing to changes in stress biomarker responses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dysfunctional stress responses in chronic pain.

PubMed

Woda, Alain; Picard, Pascale; Dutheil, Frédéric

2016-09-01

Many dysfunctional and chronic pain conditions overlap. This review describes the different modes of chronic deregulation of the adaptive response to stress which may be a common factor for these conditions. Several types of dysfunction can be identified within the hypothalamo-pituitary-adrenal axis: basal hypercortisolism, hyper-reactivity, basal hypocortisolism and hypo-reactivity. Neuroactive steroid synthesis is another component of the adaptive response to stress. Dehydroepiandrosterone (DHEA) and its sulfated form DHEA-S, and progesterone and its derivatives are synthetized in cutaneous, nervous, and adipose cells. They are neuroactive factors that act locally. They may have a role in the localization of the symptoms and their levels can vary both in the central nervous system and in the periphery. Persistent changes in neuroactive steroid levels or precursors can induce localized neurodegeneration. The autonomic nervous system is another component of the stress response. Its dysfunction in chronic stress responses can be expressed by decreased basal parasympathethic activity, increased basal sympathetic activity or sympathetic hyporeactivity to a stressful stimulus. The immune and genetic systems also participate. The helper-T cells Th1 secrete pro-inflammatory cytokines such as IL-1-β, IL-2, IL-6, IL-8, IL-12, IFN-γ, and TNF-α, whereas Th2 secrete anti-inflammatory cytokines: IL-4, IL-10, IGF-10, IL-13. Chronic deregulation of the Th1/Th2 balance can occur in favor of anti- or pro-inflammatory direction, locally or systemically. Individual vulnerability to stress can be due to environmental factors but can also be genetically influenced. Genetic polymorphisms and epigenetics are the main keys to understanding the influence of genetics on the response of individuals to constraints. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nitrogen stress response and stringent response are coupled in Escherichia coli

PubMed Central

Brown, Daniel R.; Barton, Geraint; Pan, Zhensheng; Buck, Martin; Wigneshweraraj, Sivaramesh

2014-01-01

Assimilation of nitrogen is an essential process in bacteria. The nitrogen regulation stress response is an adaptive mechanism used by nitrogen-starved Escherichia coli to scavenge for alternative nitrogen sources and requires the global transcriptional regulator NtrC. In addition, nitrogen-starved E. coli cells synthesize a signal molecule, guanosine tetraphosphate (ppGpp), which serves as an effector molecule of many processes including transcription to initiate global physiological changes, collectively termed the stringent response. The regulatory mechanisms leading to elevated ppGpp levels during nutritional stresses remain elusive. Here, we show that transcription of relA, a key gene responsible for the synthesis of ppGpp, is activated by NtrC during nitrogen starvation. The results reveal that NtrC couples these two major bacterial stress responses to manage conditions of nitrogen limitation, and provide novel mechanistic insights into how a specific nutritional stress leads to elevating ppGpp levels in bacteria. PMID:24947454

The Effects of Prenatal Maternal Stress on Early Temperament: The 2011 Queensland Flood Study.

PubMed

Simcock, Gabrielle; Elgbeili, Guillaume; Laplante, David P; Kildea, Sue; Cobham, Vanessa; Stapleton, Helen; Austin, Marie-Paule; Brunet, Alain; King, Suzanne

2017-06-01

This study examined the effects of disaster-related prenatal maternal stress on infant temperament and whether the sex of the infant or the timing of the stressor in pregnancy would moderate the effects. Mothers' objective experiences of a sudden-onset flood in Queensland, Australia, their subjective emotional reactions, and cognitive appraisal of the event were assessed. At 6 months postpartum, 121 mothers reported their infant's temperament on the 5 dimensions of the Short Temperament Scale for Infants. When controlling for postnatal maternal factors, subjective prenatal maternal stress and cognitive appraisal of the disaster were associated with easier aspects of infant temperament. However, several interesting interactions emerged showing negative effects of the flood. With higher levels of objective hardship in pregnancy, boys (but not girls) received more irritable temperament ratings. When the flood occurred early in pregnancy, higher levels of objective hardship predicted more arrhythmic infant temperament. Finally, mothers whose emotional response to the flood exceeded the hardship they endured reported significantly more active-reactive infants. Prenatal maternal stress from a natural disaster predicted more difficult temperament ratings that were moderated by infant sex, timing of the flood in gestation, and mother's emotional response to the disaster.

2016 Microbial Stress Response GRC/GRS

DTIC Science & Technology

2016-09-13

Holyoke College South Hadley, MA Chairs: Eduardo A. Groisman & Dianne K. Newman Vice Chairs: Petra A. Levin & William W. Navarre Contributors...by Discussion Leader 9:10 am - 9:35 am Martin Ackermann (ETH Zurich, Switzerland) "History-Dependence in Bacterial Stress Response – Scaling up from...Government. Microbial Stress Response GRC – Registration List Ackermann, Martin ETH Zurich Speaker Registered Andersson, Dan I Uppsala

Serum Response Factor (SRF) Ablation Interferes with Acute Stress-Associated Immediate and Long-Term Coping Mechanisms.

PubMed

Zimprich, Annemarie; Mroz, Gabi; Meyer Zu Reckendorf, Christopher; Anastasiadou, Sofia; Förstner, Philip; Garrett, Lillian; Hölter, Sabine M; Becker, Lore; Rozman, Jan; Prehn, Cornelia; Rathkolb, Birgit; Moreth, Kristin; Wurst, Wolfgang; Klopstock, Thomas; Klingenspor, Martin; Adamski, Jerzy; Wolf, Eckhard; Bekeredjian, Raffi; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabe; Knöll, Bernd

2017-12-01

Stress experience modulates behavior, metabolism, and energy expenditure of organisms. One molecular hallmark of an acute stress response is a rapid induction of immediate early genes (IEGs) such as c-Fos and Egr family members. IEG transcription in neurons is mediated by the neuronal activity-driven gene regulator serum response factor (SRF). We show a first role of SRF in immediate and long-lasting acute restraint stress (AS) responses. For this, we employed a standardized mouse phenotyping protocol at the German Mouse Clinic (GMC) including behavioral, metabolic, and cardiologic tests as well as gene expression profiling to analyze the consequences of forebrain-specific SRF deletion in mice exposed to AS. Adult mice with an SRF deletion in glutamatergic neurons (Srf; CaMKIIa-CreERT2 ) showed hyperactivity, decreased anxiety, and impaired working memory. In response to restraint AS, instant stress reactivity including locomotor behavior and corticosterone induction was impaired in Srf mutant mice. Interestingly, even several weeks after previous AS exposure, SRF-deficient mice showed long-lasting AS-associated changes including altered locomotion, metabolism, energy expenditure, and cardiovascular changes. This suggests a requirement of SRF for mediating long-term stress coping mechanisms in wild-type mice. SRF ablation decreased AS-mediated IEG induction and activity of the actin severing protein cofilin. In summary, our data suggest an SRF function in immediate AS reactions and long-term post-stress-associated coping mechanisms.

Emotional non-acceptance links early life stress and blunted cortisol reactivity to social threat.

PubMed

Cărnuţă, Mihai; Crişan, Liviu G; Vulturar, Romana; Opre, Adrian; Miu, Andrei C

2015-01-01

Early life stress (ELS) has been recently associated with blunted cortisol reactivity and emotion dysregulation, but no study until now examined whether these characteristics are related. The main goal of this study was to examine the potential mediator role of emotion dysregulation in the relation between ELS and cortisol reactivity to social threat. Only women who were free of psychiatric and endocrine disorders, had regular menstrual cycle and did not use oral contraceptives were selected for this study (N=62). After filling in ELS and multidimensional emotion dysregulation measures, participants underwent the Trier Social Stress Test during which cortisol and autonomic responses were assessed. Most participants (85.5%) reported one or more major stressful events (i.e., physical abuse, sexual abuse, major parental conflicts, death of a family or close friend, severe illness) experienced before age 17. ELS was negatively associated with cortisol reactivity and positively associated with skin conductance level (SCL) reactivity, but it did not influence heart rate and respiratory sinus arrhythmia. In addition, ELS was positively related to emotional non-acceptance (i.e., a tendency to develop secondary emotional responses to one's negative emotions), and the latter was negatively related to cortisol responses and positively related to SCL responses. Bootstrapping analyses indicated that emotional non-acceptance was a significant mediator in the relationships between ELS and both cortisol and SCL responses. Emotional non-acceptance is thus one of the psychological mechanisms underlying blunted cortisol and increased sympathetic reactivity in young healthy volunteers with a history of ELS. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comfort food is comforting to those most stressed: evidence of the chronic stress response network in high stress women.

PubMed

Tomiyama, A Janet; Dallman, Mary F; Epel, Elissa S

2011-11-01

Chronically stressed rodents who are allowed to eat calorie-dense "comfort" food develop greater mesenteric fat, which in turn dampens hypothalamic-pituitary-adrenocortical (HPA) axis activity. We tested whether similar relations exist in humans, at least cross-sectionally. Fifty-nine healthy premenopausal women were exposed to a standard laboratory stressor to examine HPA response to acute stress and underwent diurnal saliva sampling for basal cortisol and response to dexamethasone administration. Based on perceived stress scores, women were divided into extreme quartiles of low versus high stress categories. We found as hypothesized that the high stress group had significantly greater BMI and sagittal diameter, and reported greater emotional eating. In response to acute lab stressor, the high stress group showed a blunted cortisol response, lower diurnal cortisol levels, and greater suppression in response to dexamethasone. These cross-sectional findings support the animal model, which suggests that long-term adaptation to chronic stress in the face of dense calories result in greater visceral fat accumulation (via ingestion of calorie-dense food), which in turn modulates HPA axis response, resulting in lower cortisol levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

Corn response to climate stress detected with satellite-based NDVI time series

DOE PAGES

Wang, Ruoyu; Cherkauer, Keith; Bowling, Laura

2016-03-23

Corn growth conditions and yield are closely dependent on climate variability. Leaf growth, measured as the leaf area index, can be used to identify changes in crop growth in response to climate stress. This research was conducted to capture patterns of spatial and temporal corn leaf growth under climate stress for the St. Joseph River watershed, in northeastern Indiana. Leaf growth is represented by the Normalized Difference Vegetative Index (NDVI) retrieved from multiple years (2000–2010) of Landsat 5 TM images. By comparing NDVI values for individual image dates with the derived normal curve, the response of crop growth to environmentalmore » factors is quantified as NDVI residuals. Regression analysis revealed a significant relationship between yield and NDVI residual during the pre-silking period, indicating that NDVI residuals reflect crop stress in the early growing period that impacts yield. Both the mean NDVI residuals and the percentage of image pixels where corn was under stress (risky pixel rate) are significantly correlated with water stress. Dry weather is prone to hamper potential crop growth, with stress affecting most of the observed corn pixels in the area. Oversupply of rainfall at the end of the growing season was not found to have a measurable effect on crop growth, while above normal precipitation earlier in the growing season reduces the risk of yield loss at the watershed scale. Furthermore, the spatial extent of stress is much lower when precipitation is above normal than under dry conditions, masking the impact of small areas of yield loss at the watershed scale.« less

Corn response to climate stress detected with satellite-based NDVI time series

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Ruoyu; Cherkauer, Keith; Bowling, Laura

Corn growth conditions and yield are closely dependent on climate variability. Leaf growth, measured as the leaf area index, can be used to identify changes in crop growth in response to climate stress. This research was conducted to capture patterns of spatial and temporal corn leaf growth under climate stress for the St. Joseph River watershed, in northeastern Indiana. Leaf growth is represented by the Normalized Difference Vegetative Index (NDVI) retrieved from multiple years (2000–2010) of Landsat 5 TM images. By comparing NDVI values for individual image dates with the derived normal curve, the response of crop growth to environmentalmore » factors is quantified as NDVI residuals. Regression analysis revealed a significant relationship between yield and NDVI residual during the pre-silking period, indicating that NDVI residuals reflect crop stress in the early growing period that impacts yield. Both the mean NDVI residuals and the percentage of image pixels where corn was under stress (risky pixel rate) are significantly correlated with water stress. Dry weather is prone to hamper potential crop growth, with stress affecting most of the observed corn pixels in the area. Oversupply of rainfall at the end of the growing season was not found to have a measurable effect on crop growth, while above normal precipitation earlier in the growing season reduces the risk of yield loss at the watershed scale. Furthermore, the spatial extent of stress is much lower when precipitation is above normal than under dry conditions, masking the impact of small areas of yield loss at the watershed scale.« less

Associations between circadian and stress response cortisol in children.

PubMed

Simons, Sterre S H; Cillessen, Antonius H N; de Weerth, Carolina

2017-01-01

Hypothalamic-pituitary-adrenal (HPA) axis functioning is characterized by the baseline production of cortisol following a circadian rhythm, as well as by the superimposed production of cortisol in response to a stressor. However, it is relatively unknown whether the basal cortisol circadian rhythm is associated with the cortisol stress response in children. Since alterations in cortisol stress responses have been associated with mental and physical health, this study investigated whether the cortisol circadian rhythm is associated with cortisol stress responses in 6-year-old children. To this end, 149 normally developing children (M age  = 6.09 years; 70 girls) participated in an innovative social evaluative stress test that effectively provoked increases in cortisol. To determine the cortisol stress response, six cortisol saliva samples were collected and two cortisol stress response indices were calculated: total stress cortisol and cortisol stress reactivity. To determine children's cortisol circadian rhythm eight cortisol circadian samples were collected during two days. Total diurnal cortisol and diurnal cortisol decline scores were calculated as indices of the cortisol circadian rhythm. Hierarchical regression analyses indicated that higher total diurnal cortisol as well as a smaller diurnal cortisol decline, were both uniquely associated with higher total stress cortisol. No associations were found between the cortisol circadian rhythm indices and cortisol stress reactivity. Possible explanations for the patterns found are links with children's self-regulatory capacities and parenting quality.

The early response during the interaction of fungal phytopathogen and host plant.

PubMed

Shen, Yilin; Liu, Na; Li, Chuang; Wang, Xin; Xu, Xiaomeng; Chen, Wan; Xing, Guozhen; Zheng, Wenming

2017-05-01

Plants can be infected by a variety of pathogens, most of which can cause severe economic losses. The plants resist the invasion of pathogens via the innate or acquired immune system for surviving biotic stress. The associations between plants and pathogens are sophisticated beyond imaging and the interactions between them can occur at a very early stage after their touching each other. A number of researchers in the past decade have shown that many biochemical events appeared even as early as 5 min after their touching for plant disease resistance response. The early molecular interactions of plants and pathogens are likely to involve protein phosphorylation, ion fluxes, reactive oxygen species (ROS) and other signalling transduction. Here, we reviewed the recent progress in the study for molecular interaction response of fungal pathogens and host plant at the early infection stage, which included many economically important crop fungal pathogens such as cereal rust fungi, tomato Cladosporium fulvum , rice blast and so on. By dissecting the earlier infection stage of the diseases, the avirulent/virulent genes of pathogen or resistance genes of plant could be defined more clearly and accurately, which would undoubtedly facilitate fungal pathogenesis study and resistant crop breeding. © 2017 The Authors.

The early response during the interaction of fungal phytopathogen and host plant

PubMed Central

Shen, Yilin; Liu, Na; Li, Chuang; Wang, Xin; Xu, Xiaomeng; Chen, Wan; Xing, Guozhen

2017-01-01

Plants can be infected by a variety of pathogens, most of which can cause severe economic losses. The plants resist the invasion of pathogens via the innate or acquired immune system for surviving biotic stress. The associations between plants and pathogens are sophisticated beyond imaging and the interactions between them can occur at a very early stage after their touching each other. A number of researchers in the past decade have shown that many biochemical events appeared even as early as 5 min after their touching for plant disease resistance response. The early molecular interactions of plants and pathogens are likely to involve protein phosphorylation, ion fluxes, reactive oxygen species (ROS) and other signalling transduction. Here, we reviewed the recent progress in the study for molecular interaction response of fungal pathogens and host plant at the early infection stage, which included many economically important crop fungal pathogens such as cereal rust fungi, tomato Cladosporium fulvum, rice blast and so on. By dissecting the earlier infection stage of the diseases, the avirulent/virulent genes of pathogen or resistance genes of plant could be defined more clearly and accurately, which would undoubtedly facilitate fungal pathogenesis study and resistant crop breeding. PMID:28469008

Early life socioeconomic status, chronic physiological stress and hippocampal N-acetyl aspartate concentrations.

PubMed

McLean, John; Krishnadas, Rajeev; Batty, G David; Burns, Harry; Deans, Kevin A; Ford, Ian; McConnachie, Alex; McGinty, Agnes; McLean, Jennifer S; Millar, Keith; Sattar, Naveed; Shiels, Paul G; Tannahill, Carol; Velupillai, Yoga N; Packard, Chris J; Condon, Barrie R; Hadley, Donald M; Cavanagh, Jonathan

2012-12-01

Early life socioeconomic deprivation has been associated with cognitive and behavioural changes that persist through towards adulthood. In this study, we investigated whether early life socioeconomic status is associated with changes in the hippocampus N-acetyl aspartate (NAA), using the non-invasive technique of magnetic resonance spectroscopy (MRS). We performed proton magnetic resonance spectroscopy ((1)H-MRS) of the hippocampus at 3T in 30 adult males, selected from the PSOBID cohort. We conducted multiple regression analysis to examine the relationship between early socioeconomic status (SES) and concentration of N-acetyl-aspartate in the hippocampus. We also examined whether the relationship between these variables was mediated by markers of chronic physiological stress. Greater socioeconomic deprivation was associated with lower hippocampal NAA concentrations bilaterally. The relationship between early life SES and hippocampal NAA concentrations was mediated by allostatic load index - a marker of chronic physiological stress. Greater early life socioeconomic deprivation was associated with lower concentrations of NAA reflecting lesser neuronal integrity. This relationship was mediated by greater physiological stress. Further work, to better understand the biological processes underlying the effects of poverty, physiological stress on hippocampal metabolites is necessary. Copyright © 2012 Elsevier B.V. All rights reserved.

Job stress factors, stress response, and social support in association with insomnia of Japanese male workers.

PubMed

Nishitani, Naoko; Sakakibara, Hisataka

2010-01-01

The aim of the present study was to examine the relation of insomnia with job stress factors, stress response, and social support. A self-completed questionnaire survey was conducted in 212 male Japanese workers at a synthetic fiber plant. With regard to insomnia, subjects were asked the first 5 of the 8 questions on the Athens Insomnia Scale (AIS). Job stress factors, stress response and social support were assessed using the Job Stress Questionnaire. Multiple regression analyses showed that psychological job stress factors of poor appropriateness of work and high qualitative workload were associated with insomnia. The psychological stress response of depression and physical stress responses were also related with insomnia. Depression was also related to appropriateness of work. The present results showed that insomnia was closely related with the psychological job stress factor of appropriateness of work and the psychological response of depression. These mutual relationships between insomnia and poor mental health need be investigated further.

Stress Response and Artemisinin Resistance in Malaria Parasite

DTIC Science & Technology

2017-07-01

AWARD NUMBER: W81XWH-16-1-0241 TITLE: Stress Response and Artemisinin Resistance in Malaria Parasite PRINCIPAL INVESTIGATOR: Juan C. Pizarro...SUBTITLE Stress Response and Artemisinin Resistance in Malaria Parasite 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-16-1-0241 5c. PROGRAM ELEMENT...explored the role of GRP78, a protein chaperone from the stress response, in arteminisin resistant parasites. The GRP78 expression at the mRNA and

Global Effects of Early Life Stress on Neurons and Glial Cells.

PubMed

Duenas, Zulma; Caicedo-Mera, Juan Carlos; Torner, Luz

2018-02-12

Early life stress is considered a risk factor for the development of many diseases in both adolescence and adulthood. It has been reported that chronic stress (for instance, due to maternal separation during breast feeding), causes damage to the central nervous system at the level of neurons and glial cells, which are reflected in behavioral disturbances and susceptibility to the development of primarily emotional psychopathology. The aim of this review is to identify the overall state of the scientific literature that relates the information about the consequences of early life stress, contextualizing the mechanisms that may be altered, the behavioral consequences that have been studied and the possible dimorphic effects and its causes. At the end a short overview of pharmacological treatments that have been proposed to reduce the behavioral and neuroendocrine consequences caused by early life stress is presented. This review pretends to integrate general but relevant information based primarily on studies in animal models, which allow the experimental approach and the study of the mechanisms involved. A series of questions remains for reflection and surely will be answered in the near future. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Inhibition of Reticulon-1A-Mediated Endoplasmic Reticulum Stress in Early AKI Attenuates Renal Fibrosis Development.

PubMed

Fan, Ying; Xiao, Wenzhen; Lee, Kyung; Salem, Fadi; Wen, Jiejun; He, Li; Zhang, Jing; Fei, Yang; Cheng, Dongsheng; Bao, Hongda; Liu, Yumei; Lin, Fujun; Jiang, Gengru; Guo, Zhiyong; Wang, Niansong; He, John Cijiang

2017-07-01

Several animal studies have shown an important role for endoplasmic reticulum (ER) stress in AKI, whereas human studies are lacking. We recently reported that Reticulon-1A (RTN1A) is a key mediator of ER stress and kidney cell injury. Here, we investigated whether modulation of RTN1A expression during AKI contributes to the progression to CKD. In a retrospective study of 51 patients with AKI, increased expression of RTN1A and other ER stress markers were associated with the severity of kidney injury and with progression to CKD. In an inducible tubular cell-specific RTN1A-knockdown mouse model subjected to folic acid nephropathy (FAN) or aristolochic acid nephropathy, reduction of RTN1A expression during the initial stage of AKI attenuated ER stress and kidney cell injury in early stages and renal fibrosis development in later stages. Treatment of wild-type mice with tauroursodeoxycholic acid, an inhibitor of ER stress, after the induction of kidney injury with FA facilitated renoprotection similar to that observed in RTN1A-knockdown mice. Conversely, in transgenic mice with inducible tubular cell-specific overexpression of RTN1A subjected to FAN, induction of RTN1A overexpression aggravated ER stress and renal injury at the early stage and renal fibrosis at the late stage of FAN. Together, our human and mouse data suggest that the RTN1A-mediated ER stress response may be an important determinant in the severity of AKI and maladaptive repair that may promote progression to CKD. Copyright © 2017 by the American Society of Nephrology.

Coping as a mediator of the relationship between stress mindset and psychological stress response: a pilot study.

PubMed

Horiuchi, Satoshi; Tsuda, Akira; Aoki, Shuntaro; Yoneda, Kenichiro; Sawaguchi, Yusuke

2018-01-01

Coping, the cognitive and behavioral effort required to manage the effects of stressors, is important in determining psychological stress responses (ie, the emotional, behavioral, and cognitive responses to stressors). Coping was classified into categories of emotional expression (eg, negative feelings and thoughts), emotional support seeking (eg, approaching loved ones to request encouragement), cognitive reinterpretation (eg, reframing a problem positively), and problem solving (eg, working to solve the problem). Stress mindset refers to the belief that stress has enhancing (stress-is-enhancing mindset) or debilitating consequences (stress-is-debilitating mindset). This study examined whether coping mediated the relationship between stress mindset and psychological stress responses. Psychological stress responses were conceptualized as depression-anxiety, irritability-anger, and helplessness. The following two hypotheses were tested: 1) a stronger stress-is-enhancing mindset is associated with less frequent use of emotional expression, emotional support seeking, and problem solving, which in turn is associated with lower levels of depression-anxiety, irritability-anger, and helplessness; 2) a stronger stress-is-debilitating mindset is associated with more frequent use of these coping strategies, which in turn is associated with higher levels of these psychological stress responses. The participants were 30 male and 94 female undergraduate and graduate students (mean age =20.4 years). Stress mindset, coping, and psychological stress responses were measured using self-report questionnaires. Six mediation analyses were performed with stress-is-enhancing mindset or stress-is-debilitating mindset as the independent variable, one of the psychological stress responses as the dependent variable, and the four coping strategies as mediators. Emotional expression partially mediated the relationship between a strong stress-is-debilitating mindset and higher irritability

Coping as a mediator of the relationship between stress mindset and psychological stress response: a pilot study

PubMed Central

Horiuchi, Satoshi; Tsuda, Akira; Aoki, Shuntaro; Yoneda, Kenichiro; Sawaguchi, Yusuke

2018-01-01

Background Coping, the cognitive and behavioral effort required to manage the effects of stressors, is important in determining psychological stress responses (ie, the emotional, behavioral, and cognitive responses to stressors). Coping was classified into categories of emotional expression (eg, negative feelings and thoughts), emotional support seeking (eg, approaching loved ones to request encouragement), cognitive reinterpretation (eg, reframing a problem positively), and problem solving (eg, working to solve the problem). Stress mindset refers to the belief that stress has enhancing (stress-is-enhancing mindset) or debilitating consequences (stress-is-debilitating mindset). This study examined whether coping mediated the relationship between stress mindset and psychological stress responses. Psychological stress responses were conceptualized as depression-anxiety, irritability-anger, and helplessness. The following two hypotheses were tested: 1) a stronger stress-is-enhancing mindset is associated with less frequent use of emotional expression, emotional support seeking, and problem solving, which in turn is associated with lower levels of depression-anxiety, irritability-anger, and helplessness; 2) a stronger stress-is-debilitating mindset is associated with more frequent use of these coping strategies, which in turn is associated with higher levels of these psychological stress responses. Materials and methods The participants were 30 male and 94 female undergraduate and graduate students (mean age =20.4 years). Stress mindset, coping, and psychological stress responses were measured using self-report questionnaires. Six mediation analyses were performed with stress-is-enhancing mindset or stress-is-debilitating mindset as the independent variable, one of the psychological stress responses as the dependent variable, and the four coping strategies as mediators. Results Emotional expression partially mediated the relationship between a strong stress

Stress-Related Gene Expression Reflects Morphophysiological Responses to Water Deficit.

PubMed

Rymaszewski, Wojciech; Vile, Denis; Bediee, Alexis; Dauzat, Myriam; Luchaire, Nathalie; Kamrowska, Dominika; Granier, Christine; Hennig, Jacek

2017-07-01

Acclimation to water deficit (WD) enables plants to maintain growth under unfavorable environmental conditions, although the mechanisms are not completely understood. In this study, the natural variation of long-term acclimation to moderate and severe soil WD was investigated in 18 Arabidopsis ( Arabidopsis thaliana ) accessions using PHENOPSIS, an automated phenotyping platform. Soil water content was adjusted at an early stage of plant development and maintained at a constant level until reproductive age was achieved. The accessions were selected based on the expression levels of ANNEXIN1 , a drought-related marker. Severe WD conditions had a greater effect on most of the measured morphophysiological traits than moderate WD conditions. Multivariate analyses indicated that trait responses associated with plant size and water management drove most of the variation. Accessions with similar responses at these two levels were grouped in clusters that displayed different response strategies to WD The expression levels of selected stress-response genes revealed large natural variation under WD conditions. Responses of morphophysiological traits, such as projected rosette area, transpiration rate, and rosette water content, were correlated with changes in the expression of stress-related genes, such as NINE-CIS-EPOXYCAROTENOID DIOXYGENASE3 and N-MYC DOWNREGULATED-LIKE1 ( NDL1 ), in response to WD Interestingly, the morphophysiological acclimation response to WD also was reflected in the gene expression levels (most notably those of NDL1 , CHALCONE SYNTHASE , and MYB DOMAIN PROTEIN44 ) in plants cultivated under well-watered conditions. Our results may lead to the development of biomarkers and predictors of plant morphophysiological responses based on gene expression patterns. © 2017 American Society of Plant Biologists. All Rights Reserved.

Generational differences in response to desiccation stress in the desert moss Tortula inermis.

PubMed

Stark, Lloyd R; Oliver, Melvin J; Mishler, Brent D; McLetchie, D Nicholas

2007-01-01

Active growth in post-embryonic sporophytes of desert mosses is restricted to the cooler, wetter months. However, most desert mosses have perennial gametophytes. It is hypothesized that these life history patterns are due, in part, to a reduced desiccation tolerance for sporophytes relative to gametophytes. Gametophytes with attached post-embryonic sporophytes of Tortula inermis (early seta elongation phenophase) were exposed to two levels of desiccation stress, one rapid-dry cycle and two rapid-dry cycles, then moistened and allowed to recover, resume development, and/or regenerate for 35 d in a growth chamber. Gametophytes tolerated the desiccation treatments well, with 93 % survival through regenerated shoot buds and/or protonemata. At the high stress treatment, a significantly higher frequency of burned leaves and browned shoots occurred. Sporophytes were far more sensitive to desiccation stress, with only 23 % surviving after the low desiccation stress treatment, and 3 % surviving after the high desiccation stress treatment. While the timing of protonemal production and sporophytic phenophases was relatively unaffected by desiccation stress, shoots exposed to one rapid-dry cycle produced shoots more rapidly than shoots exposed to two rapid-dry cycles. It is concluded that sporophytes of Tortula inermis are more sensitive to rapid drying than are maternal gametophytes, and that sporophyte abortion in response to desiccation results from either reduced desiccation tolerance of sporophytes relative to gametophytes, or from a termination of the sporophyte on the part of the gametophyte in response to stress.

Stressors, Resources, and Stress Responses in Pregnant African American Women

PubMed Central

Giurgescu, Carmen; Kavanaugh, Karen; Norr, Kathleen F.; Dancy, Barbara L.; Twigg, Naomi; McFarlin, Barbara L.; Engeland, Christopher G.; Hennessy, Mary Dawn; White-Traut, Rosemary C.

2013-01-01

This research aimed to develop an initial understanding of the stressors, stress responses, and personal resources that impact African American women during pregnancy, potentially leading to preterm birth. Guided by the ecological model, a prospective, mixed-methods, complementarity design was used with 11 pregnant women and 8 of their significant others. Our integrated analysis of quantitative and qualitative data revealed 2 types of stress responses: high stress responses (7 women) and low stress responses (4 women). Patterns of stress responses were seen in psychological stress and cervical remodeling (attenuation or cervical length). All women in the high stress responses group had high depression and/or low psychological well-being and abnormal cervical remodeling at one or both data collection times. All but 1 woman had at least 3 sources of stress (racial, neighborhood, financial, or network). In contrast, 3 of the 4 women in the low stress responses group had only 2 sources of stress (racial, neighborhood, financial, or network) and 1 had none; these women also reported higher perceived support. The findings demonstrate the importance of periodically assessing stress in African American women during pregnancy, particularly related to their support network as well as the positive supports they receive. PMID:23360946

Bifidobacterium CECT 7765 modulates early stress-induced immune, neuroendocrine and behavioral alterations in mice.

PubMed

Moya-Pérez, A; Perez-Villalba, A; Benítez-Páez, A; Campillo, I; Sanz, Y

2017-10-01

Emerging evidence suggests that there is a window of opportunity within the early developmental period, when microbiota-based interventions could play a major role in modulating the gut-brain axis and, thereby, in preventing mood disorders. This study aims at evaluating the effects and mode of action of Bifidobacterium pseudocatenulatum CECT 7765 in a murine model of chronic stress induced by maternal separation (MS). C57Bl/6J male breast-fed pups were divided into four groups, which were subjected or not to MS and supplemented with placebo or B. pseudocatenulatum CECT7765 until postnatal period (P) 21 and followed-up until P41. Behavioral tests were performed and neuroendocrine parameters were analyzed including corticosterone, cytokine/chemokine concentrations and neurotransmitters. Microbiota was also analyzed in stools by 16S rRNA gene sequencing. B. pseudocatenulatum CECT 7765 administration attenuated some aspects of the excessive MS-induced stress response of the hypothalamic-pituitary-adrenal (HPA) axis, particularly corticosterone production at baseline and in response to subsequent acute stress in adulthood. B. pseudocatenulatum CECT 7765 also down-regulated MS-induced intestinal inflammation (reducing interferon gamma [IFN-γ]) and intestinal hypercatecholaminergic activity (reducing dopamine [DA] and adrenaline [A] concentrations) at P21. These effects have a long-term impact on the central nervous system (CNS) of adult mice since MS mice fed B. pseudocatenulatum CECT 7765 showed lower anxiety levels than placebo-fed MS mice, as well as normal neurotransmitter levels in the hypothalamus. The anti-inflammatory effect of B. pseudocatenulatum CECT 7765 seemed to be related to an improvement in glucocorticoid sensitivity in mesenteric lymph node immunocompetent cells at P21. The administration of B. pseudocatenulatum CECT 7765 to MS animals also reversed intestinal dysbiosis affecting the proportions of ten Operational Taxonomic Units (OTUs) at P21, which

Early response to venlafaxine antidepressant correlates with lower ACTH levels prior to pharmacological treatment.

PubMed

Araya, A V; Rojas, P; Fritsch, R; Rojas, R; Herrera, L; Rojas, G; Gatica, H; Silva, H; Fiedler, J L

2006-12-01

A link between stressful life events and development or exacerbation of depression has been established via a large body of evidence. An alteration in the regulation of the hypothalamic-pituitary-adrenal (HPA) axis in depression has also been associated with an increase in cortisol secretion. As arginine-vasopressin (AVP) plays an important role in the activation of HPA axis during stress, the present study investigated ACTH and cortisol secretory response induced by an AVP-related peptide desmopressin (ddAVP) in patients with major depression. Prior to antidepressant treatment, endocrinological parameters were evaluated and correlated with the clinical response to venlafaxine treatment, which offers a dual antidepressant action. Depressive patients with no other psychiatric pathology were evaluated with 17-item Hamilton Depression Scale (HAM-D) in order to follow-up the response to venlafaxine. After 1 wk of treatment, 60% of patients reduced their initial HAM-D score to at least 25%; this group was classified as early responders. The other group (40%) started to reduce significantly their HAM-D score after 3 wk of treatment and was classified as late responders. After 6 wk of treatment both groups have reduced HAM-D score to at least 25% of the baseline score. Prior to the pharmacological treatment, both early and late responders showed salivary cortisol rhythm and urinary free cortisol (UFC) in 24-h similar to healthy subjects. However, we did observe differences in basal ACTH secretion, showing that the late responder group had higher basal ACTH than both early responders and controls. The ddAVP challenge promoted a robust secretion of ACTH only in late responders, suggesting a different sensitivity of pituitary vasopressin receptor. The differences in clinical response to venlafaxine among depressive patients seem to be related to endocrinological parameters.

WRKY transcription factors in plant responses to stresses.

PubMed

Jiang, Jingjing; Ma, Shenghui; Ye, Nenghui; Jiang, Ming; Cao, Jiashu; Zhang, Jianhua

2017-02-01

The WRKY gene family is among the largest families of transcription factors (TFs) in higher plants. By regulating the plant hormone signal transduction pathway, these TFs play critical roles in some plant processes in response to biotic and abiotic stress. Various bodies of research have demonstrated the important biological functions of WRKY TFs in plant response to different kinds of biotic and abiotic stresses and working mechanisms. However, very little summarization has been done to review their research progress. Not just important TFs function in plant response to biotic and abiotic stresses, WRKY also participates in carbohydrate synthesis, senescence, development, and secondary metabolites synthesis. WRKY proteins can bind to W-box (TGACC (A/T)) in the promoter of its target genes and activate or repress the expression of downstream genes to regulate their stress response. Moreover, WRKY proteins can interact with other TFs to regulate plant defensive responses. In the present review, we focus on the structural characteristics of WRKY TFs and the research progress on their functions in plant responses to a variety of stresses. © 2016 Institute of Botany, Chinese Academy of Sciences.

The Role of the Transcriptional Response to DNA Replication Stress

PubMed Central

Herlihy, Anna E.; de Bruin, Robertus A.M.

2017-01-01

During DNA replication many factors can result in DNA replication stress. The DNA replication stress checkpoint prevents the accumulation of replication stress-induced DNA damage and the potential ensuing genome instability. A critical role for post-translational modifications, such as phosphorylation, in the replication stress checkpoint response has been well established. However, recent work has revealed an important role for transcription in the cellular response to DNA replication stress. In this review, we will provide an overview of current knowledge of the cellular response to DNA replication stress with a specific focus on the DNA replication stress checkpoint transcriptional response and its role in the prevention of replication stress-induced DNA damage. PMID:28257104

The Role of the Transcriptional Response to DNA Replication Stress.

PubMed

Herlihy, Anna E; de Bruin, Robertus A M

2017-03-02

During DNA replication many factors can result in DNA replication stress. The DNA replication stress checkpoint prevents the accumulation of replication stress-induced DNA damage and the potential ensuing genome instability. A critical role for post-translational modifications, such as phosphorylation, in the replication stress checkpoint response has been well established. However, recent work has revealed an important role for transcription in the cellular response to DNA replication stress. In this review, we will provide an overview of current knowledge of the cellular response to DNA replication stress with a specific focus on the DNA replication stress checkpoint transcriptional response and its role in the prevention of replication stress-induced DNA damage.

Towards Establishment of a Rice Stress Response Interactome

PubMed Central

Seo, Young-Su; Chern, Mawsheng; Bartley, Laura E.; Han, Muho; Jung, Ki-Hong; Lee, Insuk; Walia, Harkamal; Richter, Todd; Xu, Xia; Cao, Peijian; Bai, Wei; Ramanan, Rajeshwari; Amonpant, Fawn; Arul, Loganathan; Canlas, Patrick E.; Ruan, Randy; Park, Chang-Jin; Chen, Xuewei; Hwang, Sohyun; Jeon, Jong-Seong; Ronald, Pamela C.

2011-01-01

Rice (Oryza sativa) is a staple food for more than half the world and a model for studies of monocotyledonous species, which include cereal crops and candidate bioenergy grasses. A major limitation of crop production is imposed by a suite of abiotic and biotic stresses resulting in 30%–60% yield losses globally each year. To elucidate stress response signaling networks, we constructed an interactome of 100 proteins by yeast two-hybrid (Y2H) assays around key regulators of the rice biotic and abiotic stress responses. We validated the interactome using protein–protein interaction (PPI) assays, co-expression of transcripts, and phenotypic analyses. Using this interactome-guided prediction and phenotype validation, we identified ten novel regulators of stress tolerance, including two from protein classes not previously known to function in stress responses. Several lines of evidence support cross-talk between biotic and abiotic stress responses. The combination of focused interactome and systems analyses described here represents significant progress toward elucidating the molecular basis of traits of agronomic importance. PMID:21533176

Differential activation of eIF2 kinases in response to cellular stresses in Schizosaccharomyces pombe.

PubMed

Zhan, Ke; Narasimhan, Jana; Wek, Ronald C

2004-12-01

Phosphorylation of eukaryotic initiation factor-2 (eIF2) is an important mechanism mitigating cellular injury in response to diverse environmental stresses. While all eukaryotic organisms characterized to date contain an eIF2 kinase stress response pathway, the composition of eIF2 kinases differs, with mammals containing four distinct family members and the well-studied lower eukaryote Saccharomyces cerevisiae expressing only a single eIF2 kinase. We are interested in the mechanisms by which multiple eIF2 kinases interface with complex stress signals and elicit response pathways. In this report we find that in addition to two previously described eIF2 kinases related to mammalian HRI, designated Hri1p and Hri2p, the yeast Schizosaccharomyces pombe expresses a third eIF2 kinase, a Gcn2p ortholog. To delineate the roles of each eIF2 kinase, we constructed S. pombe strains expressing only a single eIF2 kinase gene or deleted for the entire eIF2 kinase family. We find that Hri2p is the primary activated eIF2 kinase in response to exposure to heat shock, arsenite, or cadmium. Gcn2p serves as the primary eIF2 kinase induced during a nutrient downshift, treatment with the amino acid biosynthetic inhibitor 3-aminotriazole, or upon exposure to high concentrations of sodium chloride. In one stress example, exposure to H(2)O(2), there is early tandem activation of both Hri2p and Gcn2p. Interestingly, with extended stress conditions there is activation of alternative secondary eIF2 kinases, suggesting that eukaryotes have mechanisms of coordinate activation of eIF2 kinase in their stress remediation responses. Deletion of these eIF2 kinases renders S. pombe more sensitive to many of these stress conditions.

The relationship between personality and the response to acute psychological stress.

PubMed

Xin, Yuanyuan; Wu, Jianhui; Yao, Zhuxi; Guan, Qing; Aleman, André; Luo, Yuejia

2017-12-04

The present study examined the relationship between personality traits and the response to acute psychological stress induced by a standardized laboratory stress induction procedure (the Trier Social Stress Test, TSST). The stress response was measured with a combination of cardiovascular reactivity, hypothalamic-pituitary-adrenal axis reactivity, and subjective affect (including positive affect, negative affect and subjective controllability) in healthy individuals. The Generalized Estimating Equations (GEE) approach was applied to account for the relationship between personality traits and stress responses. Results suggested that higher neuroticism predicted lower heart rate stress reactivity, lower cortisol stress response, more decline of positive affect and lower subjective controllability. Individuals higher in extraversion showed smaller cortisol activation to stress and less increase of negative affect. In addition, higher openness score was associated with lower cortisol stress response. These findings elucidate that neuroticism, extraversion and openness are important variables associated with the stress response and different dimensions of personality trait are associated with different aspects of the stress response.

ABA signaling in stress-response and seed development.

PubMed

Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko

2013-07-01

KEY MESSAGE : We review the recent progress on ABA signaling, especially ABA signaling for ABA-dependent gene expression, including the AREB/ABF regulon, SnRK2 protein kinase, 2C-type protein phosphatases and ABA receptors. Drought negatively impacts plant growth and the productivity of crops. Drought causes osmotic stress to organisms, and the osmotic stress causes dehydration in plant cells. Abscisic acid (ABA) is produced under osmotic stress conditions, and it plays an important role in the stress response and tolerance of plants. ABA regulates many genes under osmotic stress conditions. It also regulates gene expression during seed development and germination. The ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. ABRE-binding protein (AREB)/ABRE-binding factor (ABF) transcription factors (TFs) regulate ABRE-dependent gene expression. Other TFs are also involved in ABA-responsive gene expression. SNF1-related protein kinases 2 are the key regulators of ABA signaling including the AREB/ABF regulon. Recently, ABA receptors and group A 2C-type protein phosphatases were shown to govern the ABA signaling pathway. Moreover, recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress-response and seed development. The control of the expression of ABA signaling factors may improve tolerance to environmental stresses.

Parenting stress reduces the effectiveness of early teaching interventions for autistic spectrum disorders.

PubMed

Osborne, Lisa A; McHugh, Louise; Saunders, Jo; Reed, Phil

2008-07-01

This community-based study examined the influence of early teaching interventions on children diagnosed with Autistic Spectrum Disorders, and the dynamics between the time intensity of the interventions and parenting stress, on child outcomes. Intellectual, educational, and adaptive behavior and social functioning were all measured. Sixty-five children were divided into four groups, based on the levels of time intensity of their intervention, and on their parents' stress levels. There were gains in intellectual, educational, and adaptive behavioral and social skills, and there was a positive relationship between the time intensity of the early teaching interventions and child outcome gains. More importantly, however, high levels of parenting stress counteracted the effectiveness of the early teaching interventions.

Relation between stress and cytokine responses in inner-city mothers.

PubMed

Gruenberg, David A; Wright, Rosalind J; Visness, Cynthia M; Jaffee, Katy F; Bloomberg, Gordon R; Cruikshank, William W; Kattan, Meyer; Sandel, Megan T; Wood, Robert A; Gern, James E

2015-11-01

Women in poor urban neighborhoods have high rates of stress and allergic diseases, but whether stress or stress correlates such as depression promote inflammatory and type 2 cytokine responses is unknown. To examine associations among external stressors, perceived stress, depression, and peripheral blood mononuclear cell cytokine responses of mothers enrolled in the Urban Environment and Childhood Asthma Study and test the hypothesis that stress would be positively associated with type 2 and selected proinflammatory (tumor necrosis factor-α and interleukin-8) responses. Questionnaire data from mothers living in 4 inner cities included information about external stress, stress perception, and depression. The external stress domains (interpersonal problems, housing, and neighborhood stress) were combined into a Composite Stressor score. Peripheral blood mononuclear cells were stimulated ex vivo and cytokine responses to innate, adaptive, and polyclonal immune stimuli were compared with stress and depression scores for 469 of the 606 study participants. There were no significant positive associations between Composite Stressor scores, perceived stress, or depression scores and proinflammatory or type 2 cytokine responses, and these findings were not modified by allergy or asthma status. There were some modest associations with individual stressors and cytokine responses, but no consistent relations were noted. Depression was associated with decreased responses to some stimuli, particularly dust mite. Composite measurements of stressors, perceived stress, or depression were not positively related to proinflammatory or type 2 cytokine responses in these young urban women. These data do not support the hypothesis that these factors promote cytokine responses associated with allergy. ClinicalTrials.gov, identifier NCT00114881. Copyright © 2015. Published by Elsevier Inc.

Maternal corticosterone reduces egg fertility and hatchability and increases the numbers of early dead embryos in eggs laid by quail hens selected for exaggerated adrenocortical stress responsiveness.

PubMed

Schmidt, J B; Satterlee, D G; Treese, S M

2009-07-01

Quail hens selected for exaggerated (HS, high stress) rather than reduced (LS, low stress) plasma corticosterone (B) response to brief restraint deposit more B into their egg yolks than do LS hens. Female progeny of HS hens implanted with B also show reduced egg production when compared with female offspring of LS- and HS-control and LS-B-implanted hens. Herein, LS and HS hens were implanted (s.c.) with empty (controls, CON) or B-filled silastic tubes to assess the interactive influences of maternal B-treatment with quail stress line on egg fertility (FERT), total egg hatchability (TOTHATCH) and fertile egg hatchability, and the percentages of embryonic mortality (early dead, ED; late dead) and pipped eggs. Mean FERT was dramatically reduced in eggs of HS compared with LS hens and B-implanted compared with CON-treated hens (P < 0.0001, both cases). Line x implant treatment FERT outcomes partitioned (P < 0.05) as follows: LS-B = LS-CON > HS-CON > HS-B. In addition, TOTHATCH was also affected by line (LS > HS; P < 0.0001) and implant treatment (CON > B-implant; P < 0.0002) and line x implant treatment TOTHATCH means differed (P < 0.05) as follows: LS-CON = LS-B = HS-CON > HS-B. Fertile egg hatchability was reduced (P < 0.05) in HS-B-treated hen eggs when compared with LS-B and HS-CON hen eggs and more (P < 0.05) ED embryos were found in eggs laid by HS-B-implanted hens than in any other treatment group. Late dead and pipped egg percentages were unaffected by any treatment. The findings are important to avian geneticists because they further emphasize the benefits that selection for reduced adrenocortical responsiveness has on hen reproductive performance. The maternal B findings also warn poultry and hatchery managers that unless hen stress during egg formation is avoided, negative consequences in FERT, TOTHATCH, and ED can result, particularly in hens genetically predisposed toward exaggerated adrenal stress responsiveness.

Transcriptomes of Eight Arabidopsis thaliana Accessions Reveal Core Conserved, Genotype- and Organ-Specific Responses to Flooding Stress1[OPEN

PubMed Central

van Veen, Hans; Vashisht, Divya; Akman, Melis; Girke, Thomas; Mustroph, Angelika; Reinen, Emilie; Kooiker, Maarten; van Tienderen, Peter; Voesenek, Laurentius A.C.J.

2016-01-01

Climate change has increased the frequency and severity of flooding events, with significant negative impact on agricultural productivity. These events often submerge plant aerial organs and roots, limiting growth and survival due to a severe reduction in light reactions and gas exchange necessary for photosynthesis and respiration, respectively. To distinguish molecular responses to the compound stress imposed by submergence, we investigated transcriptomic adjustments to darkness in air and under submerged conditions using eight Arabidopsis (Arabidopsis thaliana) accessions differing significantly in sensitivity to submergence. Evaluation of root and rosette transcriptomes revealed an early transcriptional and posttranscriptional response signature that was conserved primarily across genotypes, although flooding susceptibility-associated and genotype-specific responses also were uncovered. Posttranscriptional regulation encompassed darkness- and submergence-induced alternative splicing of transcripts from pathways involved in the alternative mobilization of energy reserves. The organ-specific transcriptome adjustments reflected the distinct physiological status of roots and shoots. Root-specific transcriptome changes included marked up-regulation of chloroplast-encoded photosynthesis and redox-related genes, whereas those of the rosette were related to the regulation of development and growth processes. We identified a novel set of tolerance genes, recognized mainly by quantitative differences. These included a transcriptome signature of more pronounced gluconeogenesis in tolerant accessions, a response that included stress-induced alternative splicing. This study provides organ-specific molecular resolution of genetic variation in submergence responses involving interactions between darkness and low-oxygen constraints of flooding stress and demonstrates that early transcriptome plasticity, including alternative splicing, is associated with the ability to cope

Incentive effect on inhibitory control in adolescents with early-life stress: an antisaccade study.

PubMed

Mueller, Sven C; Hardin, Michael G; Korelitz, Katherine; Daniele, Teresa; Bemis, Jessica; Dozier, Mary; Peloso, Elizabeth; Maheu, Francoise S; Pine, Daniel S; Ernst, Monique

2012-03-01

Early-life stress (ES) such as adoption, change of caregiver, or experience of emotional neglect may influence the way in which affected individuals respond to emotional stimuli of positive or negative valence. These modified responses may stem from a direct alteration of how emotional stimuli are coded, and/or the cognitive function implicated in emotion modulation, such as self-regulation or inhibition. These ES effects have been probed on tasks either targeting reward and inhibitory function. Findings revealed deficits in both reward processing and inhibitory control in ES youths. However, no work has yet examined whether incentives can improve automatic response or inhibitory control in ES youths. To determine whether incentives would only improve self-regulated voluntary actions or generalize to automated motoric responses, participants were tested on a mixed eye movement task that included reflex-like prosaccades and voluntary controlled antisaccade eye movements. Seventeen adopted children (10 females, mean age 11.3 years) with a documented history of neglect and 29 typical healthy youths (16 females, mean age 11.9 years) performed the mixed prosaccade/antisaccade task during monetary incentive conditions or during no-incentive conditions. Across both saccade types, ES adolescents responded more slowly than controls. As expected, control participants committed fewer errors on antisaccades during the monetary incentive condition relative to the no-incentive condition. By contrast, ES youths failed to show this incentive-related improvement on inhibitory control. No significant incentive effects were found with prepotent prosaccades trials in either group. Finally, co-morbid psychopathology did not modulate the findings. These data suggest that youths with experience of early stress exhibit deficient modulation of inhibitory control by reward processes, in tandem with a reward-independent deficit in preparation for both automatic and controlled responses

In response to community violence: coping strategies and involuntary stress responses among Latino adolescents.

PubMed

Epstein-Ngo, Quyen; Maurizi, Laura K; Bregman, Allyson; Ceballo, Rosario

2013-01-01

Among poor, urban adolescents, high rates of community violence are a pressing public health concern. This study relies on a contextual framework of stress and coping to investigate how coping strategies and involuntary stress responses may both mediate and moderate the relation between exposure to community violence and psychological well-being. Our sample consists of 223 ninth grade Latino adolescents from poor, urban families. In response to community violence, these adolescents reported using an array of coping strategies as well as experiencing a number of involuntary stress responses; the most frequent coping responses were turning to religion and seeking social support. Hierarchical regression analyses demonstrated that involuntary stress responses mediated the relations between both witnessing or being victimized by violence and poorer psychological functioning, while coping strategies moderated these relations. These findings suggest that the negative psychological effects of exposure to community violence may, in part, be explained by involuntary stress responses, while religious-based coping may serve as a protective factor.

Deep Transcriptomic Analysis of Black Rockfish (Sebastes schlegelii) Provides New Insights on Responses to Acute Temperature Stress.

PubMed

Lyu, Likang; Wen, Haishen; Li, Yun; Li, Jifang; Zhao, Ji; Zhang, Simin; Song, Min; Wang, Xiaojie

2018-06-14

In the present study, we conducted an RNA-Seq analysis to characterize the genes and pathways involved in acute thermal and cold stress responses in the liver of black rockfish, a viviparous teleost that has the ability to cope with a wide range of temperature changes. A total of 584 annotated differentially expressed genes (DEGs) were identified in all three comparisons (HT vs NT, HT vs LT and LT vs NT). Based on an enrichment analysis, DEGs with a potential role in stress accommodation were classified into several categories, including protein folding, metabolism, immune response, signal transduction, molecule transport, membrane, and cell proliferation/apoptosis. Considering that thermal stress has a greater effect than cold stress in black rockfish, 24 shared DEGs in the intersection of the HT vs LT and HT vs NT groups were enriched in 2 oxidation-related gene ontology (GO) terms. Nine important heat-stress-reducing pathways were significantly identified and classified into 3 classes: immune and infectious diseases, organismal immune system and endocrine system. Eight DEGs (early growth response protein 1, bile salt export pump, abcb11, hsp70a, rtp3, 1,25-dihydroxyvitamin d(3) 24-hydroxylase, apoa4, transcription factor jun-b-like and an uncharacterized gene) were observed among all three comparisons, strongly implying their potentially important roles in temperature stress responses.

Nutritional support and the role of the stress response in critically ill children.

PubMed

Joosten, Koen F M; Kerklaan, Dorian; Verbruggen, Sascha C A T

2016-05-01

Nutrition impacts outcome in critically ill children. Based on evolving neuro-endocrine, immunologic and metabolic alterations, three different phases can be proposed during the course of illness. The different phases each demand for tailored macronutrient intakes in critically ill children. Early enteral nutrition is associated with decreased morbidity and mortality, but several misconceptions concerning the provision of enteral nutrition prevent adequate intake. Parenteral nutrition in critically ill children is associated with potential disadvantages, as nosocomial infections, but evidence on the effect on clinical outcome is lacking. Nutrient restriction early during critical illness might be beneficial for short and long-term outcomes by decreasing the incidence of side-effects and possibly by amplifying the acute catabolic stress response and stimulating autophagy and muscle integrity. Higher caloric and protein intake via the enteral route are associated with higher 60-day survival, asking for a more aggressive feeding approach in subsequent phases. Understanding the stress response to critical illness and its phases is essential for nutritional recommendations in critically ill children. Although parenteral nutrient restriction during the acute phase might be beneficial, inclining requirements ask for a more aggressive approach during the stable and recovery phase to enable recovery, growth and catch-up growth.

Transactional Associations Between Youths’ Responses to Peer Stress and Depression: The Moderating Roles of Sex and Stress Exposure

PubMed Central

Agoston, Anna Monica; Rudolph, Karen D.

2011-01-01

This study examined transactional associations between responses to peer stress and depression in youth. Specifically, it tested the hypotheses that (a) depression would predict fewer effortful responses and more involuntary, dysregulated responses to peer stress over time; and (b) fewer adaptive and more maladaptive responses would predict subsequent depression. Youth (M age = 12.41; SD = 1.19; 86 girls, 81 boys) and their maternal caregivers completed semi-structured interviews and questionnaires at three annual waves. Multi-group comparison path analyses were conducted to examine sex and stress-level differences in the proposed reciprocal-influence model. In girls and in youth exposed to high levels of peer stress, maladaptive stress responses predicted more depressive symptoms and adaptive stress responses predicted fewer depressive symptoms at each wave. These findings suggest the utility of preventive interventions for depression designed to enhance the quality of girls’ stress responses. In boys, depression predicted less adaptive and more maladaptive stress responses, but only at the second wave. These findings suggest that interventions designed to reduce boys’ depressive symptoms may help them develop more adaptive stress responses. PMID:20852929

Early-life stress and reproductive cost: A two-hit developmental model of accelerated aging?

PubMed

Shalev, Idan; Belsky, Jay

2016-05-01

Two seemingly independent bodies of research suggest a two-hit model of accelerated aging, one highlighting early-life stress and the other reproduction. The first, informed by developmental models of early-life stress, highlights reduced longevity effects of early adversity on telomere erosion, whereas the second, informed by evolutionary theories of aging, highlights such effects with regard to reproductive cost (in females). The fact that both early-life adversity and reproductive effort are associated with shorter telomeres and increased oxidative stress raises the prospect, consistent with life-history theory, that these two theoretical frameworks currently informing much research are tapping into the same evolutionary-developmental process of increased senescence and reduced longevity. Here we propose a mechanistic view of a two-hit model of accelerated aging in human females through (a) early-life adversity and (b) early reproduction, via a process of telomere erosion, while highlighting mediating biological embedding mechanisms that might link these two developmental aging processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thermally induced chronic developmental stress in coho salmon: Integrating measures of mortality, early growth and fluctuating asymmetry

USGS Publications Warehouse

Campbell, W.B.; Emlen, J.M.; Hershberger, W.K.

1998-01-01

ambient temperatures than in crosses exposed to fluctuating temperatures during embryogenesis. Observed patterns of early growth revealed no heterosis, but instead reflected maternal effects, with some crosses slowing growth and yolk utilization when exposed to fluctuating temperatures. Analyses of fluctuating asymmetry also showed no effects from heterosis. While analyses of composite asymmetry scores and branchiostegal rays were inconclusive, analyses of individual characters showed significantly higher fluctuating asymmetry in pelvic finray counts and a marginal change in the numbers of fish asymmetric for this character in crosses exposed to chronic thermal stress. In contrast, the fluctuating asymmetry in lower gillraker counts was significantly higher in crosses exposed to ambient temperatures and there were significantly more fish asymmetric for this character. Data on mortalities and fluctuating asymmetry indicate pelvic finray development was thermally stressed, while the heightened fluctuating asymmetry in lower gillraker counts under ambient temperatures was due to a greater frequency of less fit fish that had not been culled by thermal stress. Changes in early growth patterns in response to developmental stress yielded no parallel responses in meristic characters. We conclude that chronic thermal stress produced both selectively lethal and sublethal effects that directly shaped fluctuating asymmetry and fitness profiles in these crosses. Implicit in this conclusion is that developmental instability analyses can detect more than just chronic sublethal stress, thus providing substantial credence for using instability studies as proactive bioassessment methodologies.

Peer Victimization in Middle Childhood Impedes Adaptive Responses to Stress: A Pathway to Depressive Symptoms

PubMed Central

Troop-Gordon, Wendy; Rudolph, Karen D.; Sugimura, Niwako; Little, Todd D.

2015-01-01

Although associations between peer victimization in childhood and later psychopathology are well documented, surprisingly little research directly examines pathways accounting for these enduring effects. The present study addresses this issue by examining whether maladaptive responses to peer aggression (less effortful engagement coping and more involuntary responses) mediate associations between peer victimization and later depressive symptoms. Data were collected on 636 children (338 girls, 298 boys; M =8.94 years, SD =.37) for three consecutive years beginning in 3rd grade. Findings supported the proposition that peer victimization predicts lower levels of effortful engagement coping and higher levels of involuntary engagement and disengagement responses to stress. Moreover, these responses to stress helped to explain the link between 3rd-grade peer victimization and 5th-grade depressive symptoms. No sex differences in these linkages emerged. These findings build on prior theory and research by providing a more nuanced understanding of how and why peer victimization serves as an early risk factor for depressive symptoms. PMID:24730449

Peer victimization in middle childhood impedes adaptive responses to stress: a pathway to depressive symptoms.

PubMed

Troop-Gordon, Wendy; Rudolph, Karen D; Sugimura, Niwako; Little, Todd D

2015-01-01

Although associations between peer victimization in childhood and later psychopathology are well documented, surprisingly little research directly examines pathways accounting for these enduring effects. The present study addresses this issue by examining whether maladaptive responses to peer aggression (less effortful engagement coping and more involuntary responses) mediate associations between peer victimization and later depressive symptoms. Data were collected on 636 children (338 girls, 298 boys; M = 8.94 years, SD = .37) for three consecutive years beginning in 3rd grade. Findings supported the proposition that peer victimization predicts lower levels of effortful engagement coping and higher levels of involuntary engagement and disengagement responses to stress. Moreover, these responses to stress helped to explain the link between 3rd-grade peer victimization and 5th-grade depressive symptoms. No sex differences in these linkages emerged. These findings build on prior theory and research by providing a more nuanced understanding of how and why peer victimization serves as an early risk factor for depressive symptoms.

Early-life stress links 5-hydroxymethylcytosine to anxiety-related behaviors

PubMed Central

Papale, Ligia A.; Madrid, Andy; Li, Sisi; Alisch, Reid S.

2017-01-01

ABSTRACT Environmental stress contributes to the development of psychiatric disorders, including posttraumatic stress disorder and anxiety. While even acute stress alters gene expression, the molecular mechanisms underlying these changes remain largely unknown. 5-hydroxymethylcytosine (5hmC) is a novel environmentally sensitive DNA modification that is highly enriched in the brain and is associated with active transcription of neuronal genes. Here we examined behavioral and molecular alterations in adult mice that experienced an early-life stress before weaning (postnatal day 12 to 18) and found anxiety-like behaviors in adult female mice that were accompanied by correlated disruptions of hypothalamic 5hmC and gene expression in 118 genes, revealing potentially functional 5hmC (i.e., gene regulation). These genes are known and potentially novel stress-related targets, including Nr3c2, Nrxn1, Nfia, and Clip1, that have a significant enrichment for neuronal ontological functions, such as neuronal development and differentiation. Sequence motif predictions indicated that 5hmC may regulate gene expression by mediating transcription factor binding and alternative splicing of many of these transcripts. Together, these findings represent a critical step toward understanding the effects of early environment on the neuromolecular mechanisms that underlie the risk to develop anxiety disorders. PMID:28128679

Chronic Smoking, Trait Anxiety, and the Physiological Response to Stress.

PubMed

Wiggert, Nicole; Wilhelm, Frank H; Nakajima, Motohiro; al'Absi, Mustafa

2016-10-14

Both chronic smoking and trait anxiety have been associated with dysregulations in psychobiological stress response systems. However, these factors have not been studied in conjunction. We expected trait anxiety and smoking status to attenuate stress reactivity. Furthermore, we expected an allostatic load effect resulting in particularly attenuated stress reactivity in high-anxious smokers. In addition, high-anxious smokers were expected to exhibit increased urges to smoke in response to stress. 115 smokers and 37 nonsmokers, aged 18-64 years, completed a laboratory session including mental stressors such as evaluated public speaking and mental arithmetic. Trait anxiety was assessed using Spielberger's State-Trait Anxiety Inventory. Cardiovascular autonomic indices, salivary cortisol, and the desire to smoke were measured at baseline, during stressors, and at recovery. Regression analyses showed that smokers exhibited attenuated cardiovascular stress responses in comparison to nonsmokers. Higher trait anxiety predicted attenuated systolic blood pressure responses to stress. No interaction effect of smoking status and trait anxiety was found in stress response measures. Higher trait anxiety predicted an increased desire to smoke in response to stress among smokers. Results indicate that both smoking status and trait anxiety are associated with blunted sympatho-adrenal cardiovascular stress reactivity. Elevated urges to smoke in response to stress found among smokers with high trait anxiety suggest an important role of anxiety in smoking propensity and relapse.

Overexpression of Forebrain CRH During Early Life Increases Trauma Susceptibility in Adulthood

PubMed Central

Toth, Mate; Flandreau, Elizabeth I; Deslauriers, Jessica; Geyer, Mark A; Mansuy, Isabelle M; Merlo Pich, Emilio; Risbrough, Victoria B

2016-01-01

Although early-life stress is a significant risk factor for developing anxiety disorders, including posttraumatic stress disorder (PTSD), the underlying mechanisms are unclear. Corticotropin releasing hormone (CRH) is disrupted in individuals with PTSD and early-life stress and hence may mediate the effects of early-life stress on PTSD risk. We hypothesized that CRH hyper-signaling in the forebrain during early development is sufficient to increase response to trauma in adulthood. To test this hypothesis, we induced transient, forebrain-specific, CRH overexpression during early-life (pre-puberty, CRHOEdev) in double-mutant mice (Camk2a-rtta2 × tetO-Crh) and tested their behavioral and gene expression responses to the predator stress model of PTSD in adulthood. In one cohort of CRHOEdev exposed and unexposed mice, avoidance and arousal behaviors were examined 7–15 days after exposure to predator stress. In another cohort, gene expression changes in Crhr1, Crhr2, and Fkbp51 in forebrain of CRHOEdev exposed and unexposed mice were examined 7 days after predator stress. CRHOEdev induced robust increases in startle reactivity and reductions in startle inhibition independently of predator stress in both male and female mice. Avoidance behaviors after predator stress were highly dependent on sex and CRHOEdev exposure. Whereas stressed females exhibited robust avoidance responses that were not altered by CRHOEdev, males developed significant avoidance only when exposed to both CRHOEdev and stress. Quantitative real-time-PCR analysis indicated that CRHOEdev unexposed males exhibit significant changes in Crhr2 expression in the amygdala and bed nucleus stria terminalis in response to stress, whereas males exposed to CRHOEdev did not. Similar to CRHOEdev males, females exhibited no significant Crhr2 gene expression changes in response to stress. Cortical Fkbp51 expression was also significantly reduced by stress and CRHOEdev exposure in males, but not in females. These

Exposure to Violence Predicting Cortisol Response During Adolescence and Early Adulthood: Understanding Moderating Factors

PubMed Central

Heinze, Justin E.; Miller, Alison L.; Stoddard, Sarah A.; Zimmerman, Marc A.

2014-01-01

Previous research on the association between violence and biological stress regulation has been largely cross-sectional, and has also focused on childhood. Using longitudinal data from a low-income, high-risk, predominantly African-American sample (n = 266; 57 % female), we tested hypotheses about the influence of cumulative exposure to violence during adolescence and early adulthood on cortisol responses in early adulthood. We found that cumulative exposure to violence predicted an attenuated cortisol response. Further, we tested whether sex, mothers’ support, or fathers’ support moderated the effect of exposure to violence on cortisol responses. We found that the effect of cumulative exposure to violence on cortisol was modified by sex; specifically, males exposed to violence exhibited a more attenuated response pattern. In addition, the effect of cumulative exposure to violence on cortisol was moderated by the presence of fathers’ support during adolescence. The findings contribute to a better understanding of how cumulative exposure to violence influences biological outcomes, emphasizing the need to understand sex and parental support as moderators of risk. PMID:24458765

Prenatal stress programs neuroendocrine stress responses and affective behaviors in second generation rats in a sex-dependent manner.

PubMed

Grundwald, Natalia J; Brunton, Paula J

2015-12-01

An adverse environment in early life is often associated with dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis and higher rates of mood disorders in adulthood. In rats, exposure to social stress during pregnancy results in hyperactive HPA axis responses to stress in the adult offspring and heightened anxiety behavior in the males, but not the females. Here we tested whether, without further intervention, the effects of prenatal stress (PNS) in the first filial generation (F1) are transmitted to the F2 generation via the maternal line. F1 control and PNS female rats were mated with control males and housed under non-stress conditions throughout pregnancy. HPA axis responses to acute stress, anxiety- and depressive-like behavior were assessed in the adult F2 offspring. ACTH and corticosterone responses to an acute stressor were markedly enhanced in F2 PNS females compared with controls. This was associated with greater corticotropin releasing hormone (Crh) mRNA expression in the paraventricular nucleus and reduced hippocampal glucocorticoid (Gr) and mineralocorticoid receptor (Mr) mRNA expression. Conversely, in the F2 PNS males, HPA axis responses to acute stress were attenuated and hippocampal Gr mRNA expression was greater compared with controls. F2 PNS males exhibited heightened anxiety-like behavior (light-dark box and elevated plus maze) compared with F2 control males. Anxiety-like behavior did not differ between F2 control and PNS females during metestrus/diestrus, however at proestrus/estrus, F2 control females displayed a reduction in anxiety-like behavior, but this effect was not observed in the F2 PNS females. Heightened anxiety in the F2 PNS males was associated with greater Crh mRNA expression in the central nucleus of the amygdala compared with controls. Moreover, Crh receptor-1 (Crhr1) mRNA expression was significantly increased, whereas Crhr2 mRNA was significantly decreased in discrete regions of the amygdala in F2 PNS males compared

Work stress and innate immune response.

PubMed

Boscolo, P; Di Gioacchino, M; Reale, M; Muraro, R; Di Giampaolo, L

2011-01-01

Several reports highlight the relationship between blood NK cytotoxic activity and life style. Easy life style, including physical activity, healthy dietary habits as well as good mental health are characterized by an efficient immune response. Life style is related to the type of occupational activity since work has a central part in life either as source of income or contributing to represent the social identity. Not only occupational stress, but also job loss or insecurity are thus considered serious stressful situations, inducing emotional disorders which may affect both neuroendocrine and immune systems; reduced reactivity to mitogens and/or decreased blood NK cytotoxic activity was reported in unemployed workers or in those with a high perception of job insecurity and/or job stress. Although genetic factors have a key role in the pathogenesis of autoimmune disorders, occupational stress (as in night shifts) was reported associated to an increased incidence of autoimmune disorders. Monitoring blood NK response may thus be included in the health programs as an indirect index of stressful job and/or poor lifestyle.

Buffering boys and boosting girls: The protective and promotive effects of Early Head Start for children’s expressive language in the context of parenting stress

PubMed Central

Vallotton, C. D.; Harewood, T.; Ayoub, C. A.; Pan, B.; Mastergeorge, A. M.; Brophy-Herb, H.

2011-01-01

Children’s characteristics, including gender, influence their development by eliciting differential responses from their environments, and by influencing differential responses to their environments. Parenting-related stress, associated with poverty environments, negatively influences children’s language, likely through its impact on parent-child interactions, but may impact boys’ and girls’ development differently. Early intervention represents one tool for supporting development in at-risk toddlers, but gender-differences in effects of intervention are rarely described. The current studies assessed the effects of Early Head Start (EHS) on children’s productive vocabulary in the context of parenting stress and examined gender differences in program effects on vocbulary. Data were from the national EHS Research and Evaluation (EHSRE) study (Study 1, N = 3,001), and from a dataset associated with one EHSRE site (Study 2, N = 146) where additional data on productive vocabulary were collected. Study 1 found that at 24 months of age, the EHS program protected girls’ productive vocabulary from the negative effects of parenting stress, but had little impact on boys’ vocabulary. In Study 2, the local EHS site promoted girls’ vocabulary development over time from 14 to 36 months despite the negative effects of parenting stress, and protected boys’ vocabulary from the negative parenting stress effects. These results suggest differential ways in which at-risk toddlers are affected by early intervention. PMID:23166405

Cortisol responses to naturalistic and laboratory stress in student teachers: comparison with a non-stress control day.

PubMed

Wolfram, Maren; Bellingrath, Silja; Feuerhahn, Nicolas; Kudielka, Brigitte M

2013-04-01

Ambulatory assessments of hypothalamus-pituitary-adrenal axis responses to acute natural stressors yield evidence on stress regulation with high ecological validity. Sampling of salivary cortisol is a standard technique in this field. In 21 healthy student teachers, we assessed cortisol responses to a demonstration lesson. On a control day, sampling was repeated at analogous times. Additionally, the cortisol awakening response (CAR) was assessed on both days. Participants were also exposed to a laboratory stressor, the Trier Social Stress Test, and rated their individual levels of chronic work stress. In pre-to-post-stress assessment, cortisol levels declined after the lesson. However, post-stress cortisol levels were significantly higher compared with those on the control day. Also, the Trier Social Stress Test yielded higher cortisol responses when using the control day as reference baseline. Associations between the CAR and chronic stress measures were observed solely on the control day. There were no significant associations between cortisol responses to the natural and laboratory stressors. Our results indicate that a control day might be an important complement in laboratory but especially in ambulatory stress research. Furthermore, associations between chronic stress measures and the CAR might be obscured by acute stress exposure. Finally, responses to the laboratory stressor do not seem to mirror natural stress responses. Copyright © 2012 John Wiley & Sons, Ltd.

Global protein phosphorylation dynamics during deoxynivalenol-induced ribotoxic stress response in the macrophage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Xiao; Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824; Whitten, Douglas A.

Deoxynivalenol (DON), a trichothecene mycotoxin produced by Fusarium that commonly contaminates food, is capable of activating mononuclear phagocytes of the innate immune system via a process termed the ribotoxic stress response (RSR). To encapture global signaling events mediating RSR, we quantified the early temporal (≤ 30 min) phosphoproteome changes that occurred in RAW 264.7 murine macrophage during exposure to a toxicologically relevant concentration of DON (250 ng/mL). Large-scale phosphoproteomic analysis employing stable isotope labeling of amino acids in cell culture (SILAC) in conjunction with titanium dioxide chromatography revealed that DON significantly upregulated or downregulated phosphorylation of 188 proteins at bothmore » known and yet-to-be functionally characterized phosphosites. DON-induced RSR is extremely complex and goes far beyond its prior known capacity to inhibit translation and activate MAPKs. Transcriptional regulation was the main target during early DON-induced RSR, covering over 20% of the altered phosphoproteins as indicated by Gene Ontology annotation and including transcription factors/cofactors and epigenetic modulators. Other biological processes impacted included cell cycle, RNA processing, translation, ribosome biogenesis, monocyte differentiation and cytoskeleton organization. Some of these processes could be mediated by signaling networks involving MAPK-, NFκB-, AKT- and AMPK-linked pathways. Fuzzy c-means clustering revealed that DON-regulated phosphosites could be discretely classified with regard to the kinetics of phosphorylation/dephosphorylation. The cellular response networks identified provide a template for further exploration of the mechanisms of trichothecenemycotoxins and other ribotoxins, and ultimately, could contribute to improved mechanism-based human health risk assessment. - Highlights: ► Mycotoxin deoxynivalenol (DON) induces immunotoxicity via ribotoxic stress response. ► SILAC

[Influence of early childhood stress exposure and traumatic life events on pain perception].

PubMed

Tesarz, J; Gerhardt, A; Eich, W

2018-06-05

Adult pain perception is influenced substantially by interactions between mind, body, and social environment during early life. Early stress exposure and traumatic life events induce powerful psychophysical stress reactions that exert multiple neurofunctional processes. This has significant implications for pain perception and pain processing. As part of this review, the complex relationships between traumatic stress experiences and associated psychobiological mechanisms of chronic pain will be discussed. Based on selected studies, psychophysiological findings are presented and possible underlying mechanisms are discussed. The article concludes with a discussion of potential implications for treatment.

Differential sensitization of parenting on early adolescent cortisol: Moderation by profiles of maternal stress.

PubMed

Martin, Christina Gamache; Kim, Hyoun K; Fisher, Philip A

2016-05-01

The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the body's stress-response neurobiological system, and its development and functioning are shaped by the social environment. Much of our understanding of the effects of the caregiving environment on the HPA axis is based on (a) parenting in young children and (b) individual maternal stressors, such as depression. Yet, less is known about how parenting behaviors and maternal stressors interact to influence child cortisol regulation, particularly in older children. With an ethnically diverse sample of 199 mothers and their early adolescent children (M=11.00years; 54% female), a profile analytic approach was used to investigate how multiple phenotypes of maternal stress co-occur and moderate the relation between parenting behaviors and youths' diurnal cortisol rhythms. Latent profile analysis yielded 4 profiles: current parenting stress, concurrent parenting and childhood stress, childhood stress, and low stress. For mothers with the concurrent parenting and childhood stress profile, inconsistent discipline, poor parental supervision, and harsh caregiving behaviors each were related to flattened diurnal cortisol rhythms in their adolescents. For mothers with the current parenting stress and childhood stress profiles, their use of inconsistent discipline was associated with flattened diurnal cortisol rhythms in their adolescents. For mothers with the low stress profile, none of the parenting behaviors was related to their adolescents' cortisol regulation. Findings suggest that based on mothers' stress profile, parenting behaviors are differentially related to youths' diurnal cortisol rhythms. Implications for parenting interventions are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differential Sensitization of Parenting on Early Adolescent Cortisol: Moderation by Profiles of Maternal Stress

PubMed Central

Martin, Christina Gamache; Kim, Hyoun K.; Fisher, Philip A.

2016-01-01

The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the body’s stress-response neurobiological system, and its development and functioning are shaped by the social environment. Much of our understanding of the effects of the caregiving environment on the HPA axis is based on a) parenting in young children and b) individual maternal stressors, such as depression. Yet, less is known about how parenting behaviors and maternal stressors interact to influence child cortisol regulation, particularly in older children. With an ethnically diverse sample of 199 mothers and their early adolescent children (M = 11.00 years; 54% female), a profile analytic approach was used to investigate how multiple phenotypes of maternal stress co-occur and moderate the relation between parenting behaviors and youths’ diurnal cortisol rhythms. Latent profile analysis yielded 4 profiles: current parenting stress, concurrent parenting and childhood stress, childhood stress, and low stress. For mothers with the concurrent parenting and childhood stress profile, inconsistent discipline, poor parental supervision, and harsh caregiving behaviors each were related to flattened diurnal cortisol rhythms in their adolescents. For mothers with the current parenting stress and childhood stress profiles, their use of inconsistent discipline was associated with flattened diurnal cortisol rhythms in their adolescents. For mothers with the low stress profile, none of the parenting behaviors was related to their adolescents’ cortisol regulation. Findings suggest that based on mothers’ stress profile, parenting behaviors are differentially related to youths’ diurnal cortisol rhythms. Implications for parenting interventions are discussed. PMID:26859701

Reduced risk of apoptosis: mechanisms of stress responses.

PubMed

Milisav, Irina; Poljšak, Borut; Ribarič, Samo

2017-02-01

Apoptosis signaling pathways are integrated into a wider network of interconnected apoptotic and anti-apoptotic pathways that regulate a broad range of cell responses from cell death to growth, development and stress responses. An important trigger for anti- or pro-apoptotic cell responses are different forms of stress including hypoxia, energy deprivation, DNA damage or inflammation. Stress duration and intensity determine whether the cell's response will be improved cell survival, due to stress adaptation, or cell death by apoptosis, necrosis or autophagy. Although the interplay between enhanced stress tolerance and modulation of apoptosis triggering is not yet fully understood, there is a substantial body of experimental evidence demonstrating that apoptosis and anti-apoptosis signaling pathways can be manipulated to trigger or delay apoptosis in vitro or in vivo. Anti-apoptotic strategies cover a broad range of approaches. These interventions include mediators that prevent apoptosis (trophic factors and cytokines), apoptosis inhibition (caspase inhibition, stimulation of anti-apoptotic or inhibition of pro-apoptotic proteins and elimination of apoptotic stimulus), adaptive stress responses (induction of maintenance and repair, caspase inactivation) and cell-cell interactions (blocking engulfment and modified micro environment). There is a consensus that preclinical efficacy and safety evaluations of anti-apoptotic strategies should be performed with protocols that simulate as closely as possible the effects of aging, gender, risk factors, comorbidities and co-medications.

Antagonistic, overlapping and distinct responses to biotic stress in rice (Oryza sativa) and interactions with abiotic stress

PubMed Central

2013-01-01

Background Every year, substantial crop loss occurs globally, as a result of bacterial, fungal, parasite and viral infections in rice. Here, we present an in-depth investigation of the transcriptomic response to infection with the destructive bacterial pathogen Xanthomonas oryzae pv. oryzae(Xoo) in both resistant and susceptible varieties of Oryza sativa. A comparative analysis to fungal, parasite and viral infection in rice is also presented. Results Within 24 h of Xoo inoculation, significant reduction of cell wall components and induction of several signalling components, membrane bound receptor kinases and specific WRKY and NAC transcription factors was prominent, providing a framework for how the presence of this pathogen was signalled and response mounted. Extensive comparative analyses of various other pathogen responses, including in response to infection with another bacterium (Xoc), resistant and susceptible parasite infection, fungal, and viral infections, led to a proposed model for the rice biotic stress response. In this way, a conserved induction of calcium signalling functions, and specific WRKY and NAC transcription factors, was identified in response to all biotic stresses. Comparison of these responses to abiotic stress (cold, drought, salt, heat), enabled the identification of unique genes responsive only to bacterial infection, 240 genes responsive to both abiotic and biotic stress, and 135 genes responsive to biotic, but not abiotic stresses. Functional significance of a number of these genes, using genetic inactivation or over-expression, has revealed significant stress-associated phenotypes. While only a few antagonistic responses were observed between biotic and abiotic stresses, e.g. for a number of endochitinases and kinase encoding genes, some of these may be crucial in explaining greater pathogen infection and damage under abiotic stresses. Conclusions The analyses presented here provides a global view of the responses to multiple

Early life adversity potentiates the effects of later life stress on cumulative physiological dysregulation.

PubMed

Dich, Nadya; Hansen, Åse Marie; Avlund, Kirsten; Lund, Rikke; Mortensen, Erik Lykke; Bruunsgaard, Helle; Rod, Naja Hulvej

2015-01-01

Previous research indicates that early life adversity may heighten stress reactivity and impair mechanisms for adaptive coping, suggesting that experience of stress in early life may also potentiate adults' physiological vulnerability to stress in later life. The study tested this hypothesis by investigating whether the experience of stressful events and circumstances (SEC) in childhood or adolescence amplified the effect of adulthood SEC on physiological dysregulation (allostatic load, AL) in later midlife. Observational data were used in the present study. Physiological functioning was measured in later midlife (participants' age ranged from 49 to 63 years). Both childhood/adolescence and adulthood SEC were reported retrospectively on the same occasion. Participants were 5309 Danish men and women from Copenhagen Aging and Midlife Biobank (CAMB). SEC included socioeconomic and family factors. The AL index was based on nine cardiovascular, metabolic, and immune biomarkers. Experience of SEC in both early life and adulthood independently predicted higher AL. In men, experience of SEC in early life also potentiated the effect of SEC in adulthood on AL. The results provide further insight into the mechanisms behind the "biological embedding" of childhood stress.

Role of shame and body esteem in cortisol stress responses

PubMed Central

Lupis, Sarah B.; Sabik, Natalie J.

2016-01-01

Studies assessing the role of shame in HPA axis reactivity report mixed findings. Discrepancies may be due to methodological difficulties and inter-individual differences in the propensity to experience shame in a stressful situation. Hence, the current study combined self-report of shame and facial coding of shame expressions and assessed the role of body esteem as a moderator of the shame–stress link. For this, 44 healthy students (24F, age 20.5 ± 2.1 years) were exposed to an acute psychosocial stress paradigm (Trier Social Stress Test: TSST). Salivary cortisol levels were measured throughout the protocol. Trait shame was measured before the stress test, and state shame immediately afterwards. Video recordings of the TSST were coded to determine emotion expressions. State shame was neither associated with cortisol stress responses nor with body esteem (self-report: all ps ≥ .24; expression: all ps ≥ .31). In contrast, higher trait shame was associated with both negative body esteem (p = .049) and stronger cortisol stress responses (p = .013). Lastly, having lower body esteem predicted stronger cortisol stress responses (p = .022); however, it did not significantly moderate the association between shame indices and cortisol stress responses (all ps ≥ .94). These findings suggest that body esteem and trait shame independently contribute to strength of cortisol stress responses. Thus, in addition to trait shame, body esteem emerged as an important predictor of cortisol stress responses and as such, a potential contributor to stress-related negative health outcomes. PMID:26577952

A physical/psychological and biological stress combine to enhance endoplasmic reticulum stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mondal, Tapan Kumar; Emeny, Rebecca T.; Gao, Donghong

The generation of an immune response against infectious and other foreign agents is substantially modified by allostatic load, which is increased with chemical, physical and/or psychological stressors. The physical/psychological stress from cold-restraint (CR) inhibits host defense against Listeria monocytogenes (LM), due to early effects of the catecholamine norepinephrine (NE) from sympathetic nerves on β1-adrenoceptors (β1AR) of immune cells. Although CR activates innate immunity within 2 h, host defenses against bacterial growth are suppressed 2–3 days after infection (Cao and Lawrence 2002). CR enhances inducible nitric oxide synthase (iNOS) expression and NO production. The early innate activation leads to cellular reduction-oxidationmore » (redox) changes of immune cells. Lymphocytes from CR-treated mice express fewer surface thiols. Splenic and hepatic immune cells also have fewer proteins with free thiols after CR and/or LM, and macrophages have less glutathione after the in vivo CR exposure or exposure to NE in vitro. The early induction of CR-induced oxidative stress elevates endoplasmic reticulum (ER) stress, which could interfere with keeping phagocytized LM within the phagosome or re-encapsuling LM by autophagy once they escape from the phagosome. ER stress-related proteins, such as glucose-regulated protein 78 (GRP78), have elevated expression with CR and LM. The results indicate that CR enhances the unfolded protein response (UPR), which interferes with host defenses against LM. Thus, it is postulated that increased stress, as exists with living conditions at low socioeconomic conditions, can lower host defenses against pathogens because of oxidative and ER stress processes. - Highlights: • Cold-restraint (physical/psychological stress) induces early oxidative stress. • The oxidative stress relates to catecholamine signaling beta-adrenoceptors. • Physical/psychological stress combines infection enhancing inflammation. • Endoplasmic

Refining the multisystem view of the stress response: coordination among cortisol, alpha-amylase, and subjective stress in response to relationship conflict.

PubMed

Laurent, Heidemarie K; Powers, Sally I; Granger, Douglas A

2013-07-02

This study investigated associations among young adults' hypothalamic-pituitary-adrenal axis activity, autonomic nervous system activity, and subjective stress in response to interpersonal conflict to better characterize coordination across stress systems. Seven saliva samples were collected from 199 young adult opposite-sex couples before, during, and after they discussed an unresolved relationship conflict. Samples were later assayed for cortisol and alpha-amylase (sAA). Couples rated anticipatory stress prior to the conflict and perceived stress immediately following the task. Growth curve modeling was used to examine two possible levels of within-person coordination across physiological systems: alignment between cortisol and sAA responses throughout the sampling period ("matched phase coordination"), and association between overall levels of cortisol and sAA in response to conflict ("average level coordination"). Whereas both partners showed the former type of coordination, only women showed the latter type. Positive anticipation of the stressor predicted stronger cortisol-sAA matched phase coordination for women. Pre-task ratings related to women's sAA, and post-task ratings related to both partners' cortisol responses. Implications for a multisystem interpretation of normal and pathological responses to daily stress are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Refining the multisystem view of the stress response: Coordination among cortisol, alpha-amylase, and subjective stress in response to relationship conflict

PubMed Central

Powers, Sally I.; Granger, Douglas A.

2013-01-01

This study investigated associations among young adults' hypothalamic-pituitary-adrenal axis activity, autonomic nervous system activity, and subjective stress in response to interpersonal conflict to better characterize coordination across stress systems. Seven saliva samples were collected from 199 young adult opposite-sex couples before, during, and after they discussed an unresolved relationship conflict. Samples were later assayed for cortisol and alpha-amylase (sAA). Couples rated anticipatory stress prior to the conflict and perceived stress immediately following the task. Growth curve modeling was used to examine two possible levels of within-person coordination across physiological systems: alignment between cortisol and sAA responses throughout the sampling period (“matched phase coordination”), and association between overall levels of cortisol and sAA in response to conflict (“average level coordination”). Whereas both partners showed the former type of coordination, only women showed the latter type. Positive anticipation of the stressor predicted stronger cortisol-sAA matched phase coordination for women. Pre-task ratings related to women's sAA, and post-task ratings related to both partners' cortisol responses. Implications for a multisystem interpretation of normal and pathological responses to daily stress are discussed. PMID:23684904

Parenting Interventions in Early Head Start: The Buffering Toxic Stress Consortium

ERIC Educational Resources Information Center

Berlin, Lisa; Blair, Clancy; Boyd, Misty L.; Constantino, John N.; Hallam, Rena A.; Han, Myae; Hustedt, Jason; Harden, Brenda Jones; Raver, C. Cybele; Sarche, Michelle; Vu, Jennifer A.; Watamura, Sarah Enos; Meyer, Aleta; Fortunato, Christine

2013-01-01

The Buffering Toxic Stress Consortium was created by the Office of Planning, Research and Evaluation within the Administration for Children and Families to test preventive interventions for Early Head Start families facing toxic stress, as conceptualized by Shonkoff, Boyce, and McEwen in their influential 2009 article. Because relationships…

Interdependence of tetrapyrrole metabolism, the generation of oxidative stress and the mitigative oxidative stress response

PubMed Central

Busch, Andrea W.U.; Montgomery, Beronda L.

2015-01-01

Tetrapyrroles are involved in light harvesting and light perception, electron-transfer reactions, and as co-factors for key enzymes and sensory proteins. Under conditions in which cells exhibit stress-induced imbalances of photosynthetic reactions, or light absorption exceeds the ability of the cell to use photoexcitation energy in synthesis reactions, redox imbalance can occur in photosynthetic cells. Such conditions can lead to the generation of reactive oxygen species (ROS) associated with alterations in tetrapyrrole homeostasis. ROS accumulation can result in cellular damage and detrimental effects on organismal fitness, or ROS molecules can serve as signals to induce a protective or damage-mitigating oxidative stress signaling response in cells. Induced oxidative stress responses include tetrapyrrole-dependent and -independent mechanisms for mitigating ROS generation and/or accumulation. Thus, tetrapyrroles can be contributors to oxidative stress, but are also essential in the oxidative stress response to protect cells by contributing to detoxification of ROS. In this review, we highlight the interconnection and interdependence of tetrapyrrole metabolism with the occurrence of oxidative stress and protective oxidative stress signaling responses in photosynthetic organisms. PMID:25618582

Adolescent voluntary exercise attenuated hippocampal innate immunity responses and depressive-like behaviors following maternal separation stress in male rats.

PubMed

Sadeghi, Mahsa; Peeri, Maghsoud; Hosseini, Mir-Jamal

2016-09-01

Early life stressful events have detrimental effects on the brain and behavior, which are associated with the development of depression. Immune-inflammatory responses have been reported to contribute in the pathophysiology of depression. Many studies have reported on the beneficial effects of exercise against stress. However, underlying mechanisms through which exercise exerts its effects were poorly studied. Therefore, it applied maternal separation (MS), as a valid animal model of early-life adversity, in rats from postnatal day (PND) 2 to 14 for 180min per day. At PND 28, male Wistar albino rats were subjected to 5 experimental groups; 1) controls 2) MS rats 3) MS rats treated with fluoxetine 5mg/kg to PND 60, 4) MS rats that were subjected to voluntary running wheel (RW) exercise and 5) MS rats that were subjected to mandatory treadmill (TM) exercise until adulthood. At PND 60, depressive-like behaviors were assessed by using forced swimming test (FST), splash test, and sucrose preference test (SPT). Our results revealed that depressive-like behaviors following MS stress were associated with an increase in expression of toll-like receptor 4 (Tlr-4) and its main signaling protein, Myd88, in the hippocampal formation. Also, we found that voluntary (and not mandatory) physical exercise during adolescence is protected against depressant effects of early-life stress at least partly through mitigating the innate immune responses in the hippocampus. Copyright © 2016. Published by Elsevier Inc.

Chronic Smoking, Trait Anxiety, and the Physiological Response to Stress

PubMed Central

Wiggert, Nicole; Wilhelm, Frank H.; Nakajima, Motohiro; al’Absi, Mustafa

2016-01-01

Background and Objectives Both chronic smoking and trait anxiety have been associated with dysregulations in psychobiological stress response systems. However, these factors have not been studied in conjunction. We expected trait anxiety and smoking status to attenuate stress reactivity. Furthermore, we expected an allostatic load effect resulting in particularly attenuated stress reactivity in high-anxious smokers. In addition, high-anxious smokers were expected to exhibit increased urges to smoke in response to stress. Methods 115 smokers and 37 nonsmokers, aged 18 – 64 years, completed a laboratory session including mental stressors such as evaluated public speaking and mental arithmetic. Trait anxiety was assessed using Spielberger’s State-Trait Anxiety Inventory. Cardiovascular autonomic indices, salivary cortisol, and the desire to smoke were measured at baseline, during stressors, and at recovery. Results Regression analyses showed that smokers exhibited attenuated cardiovascular stress responses in comparison to nonsmokers. Higher trait anxiety predicted attenuated systolic blood pressure responses to stress. No interaction effect of smoking status and trait anxiety was found in stress response measures. Higher trait anxiety predicted an increased desire to smoke in response to stress among smokers. Conclusion Results indicate that both smoking status and trait anxiety are associated with blunted sympatho-adrenal cardiovascular stress reactivity. Elevated urges to smoke in response to stress found among smokers with high trait anxiety suggest an important role of anxiety in smoking propensity and relapse. PMID:27484702

Most oxidative stress response in water samples comes from unknown chemicals: the need for effect-based water quality trigger values.

PubMed

Escher, Beate I; van Daele, Charlotte; Dutt, Mriga; Tang, Janet Y M; Altenburger, Rolf

2013-07-02

The induction of adaptive stress response pathways is an early and sensitive indicator of the presence of chemical and non-chemical stressors in cells. An important stress response is the Nrf-2 mediated oxidative stress response pathway where electrophilic chemicals or chemicals that cause the formation of reactive oxygen species initiate the production of antioxidants and metabolic detoxification enzymes. The AREc32 cell line is sensitive to chemicals inducing oxidative stress and has been previously applied for water quality monitoring of organic micropollutants and disinfection byproducts. Here we propose an algorithm for the derivation of effect-based water quality trigger values for this end point that is based on the combined effects of mixtures of regulated chemicals. Mixture experiments agreed with predictions by the mixture toxicity concept of concentration addition. The responses in the AREc32 and the concentrations of 269 individual chemicals were quantified in nine environmental samples, ranging from treated effluent, recycled water, stormwater to drinking water. The effects of the detected chemicals could explain less than 0.1% of the observed induction of the oxidative stress response in the sample, affirming the need to use effect-based trigger values that account for all chemicals present.

Exposure of mother rats to chronic unpredictable stress before pregnancy alters the metabolism of gamma-aminobutyric acid and glutamate in the right hippocampus of offspring in early adolescence in a sexually dimorphic manner.

PubMed

Huang, Yuejun; Shen, Zhiwei; Hu, Liu; Xia, Fang; Li, Yuewa; Zhuang, Jingwen; Chen, Peishan; Huang, Qingjun

2016-12-30

There is increasing evidence that mothers' exposure to stress before or during pregnancy is linked to an incidence of psychiatric disorders in offspring. However, a few studies have estimated the role of sex in the detrimental effects of pre-gestational stress on the offspring rats at early adolescence. Sex differences regarding the metabolism of gamma-aminobutyric acid and glutamate in the right hippocampus were investigated by MRS when the offspring rats reached 30 days. Additionally, the impact of pre-gestational stress exposed on an additional short-term acute stressor, such as forced swim, was examined in the male and female offspring rats. Our findings showed female offspring rats were more vulnerable to stressful conditions for either pre-gestational stress or acute stress in early adolescence, and had decreased GABA/Cr+PCr and Glu/Cr+PCr in the right hippocampus. Interestingly, in response to forced swim, male offspring rats whose mothers were exposed to pre-gestational stress were more affected by the short-term acute stressor and this was manifested by change of Glu/GABA and Glu/Gln in the right hippocampus. These data indicated that although female offspring rats were more vulnerable to pre-gestational stress from their mothers than males, in response to an additional acute stressor they showed better response. Therefore, both sexually dimorphic manner and combination of stressful procedures should be carefully considered in the study of stress-related psychiatric disorders in early adolescence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Proteomic analysis of endoplasmic reticulum stress responses in rice seeds.

PubMed

Qian, Dandan; Tian, Lihong; Qu, Leqing

2015-09-23

The defects in storage proteins secretion in the endosperm of transgenic rice seeds often leads to endoplasmic reticulum (ER) stress, which produces floury and shrunken seeds, but the mechanism of this response remains unclear. We used an iTRAQ-based proteomics analysis of ER-stressed rice seeds due to the endosperm-specific suppression of OsSar1 to identify changes in the protein levels in response to ER stress. ER stress changed the expression of 405 proteins in rice seed by >2.0- fold compared with the wild-type control. Of these proteins, 140 were upregulated and 265 were downregulated. The upregulated proteins were mainly involved in protein modification, transport and degradation, and the downregulated proteins were mainly involved in metabolism and stress/defense responses. A KOBAS analysis revealed that protein-processing in the ER and degradation-related proteasome were the predominant upregulated pathways in the rice endosperm in response to ER stress. Trans-Golgi protein transport was also involved in the ER stress response. Combined with bioinformatic and molecular biology analyses, our proteomic data will facilitate our understanding of the systemic responses to ER stress in rice seeds.

Early-life stress impacts the developing hippocampus and primes seizure occurrence: cellular, molecular, and epigenetic mechanisms

PubMed Central

Huang, Li-Tung

2014-01-01

Early-life stress includes prenatal, postnatal, and adolescence stress. Early-life stress can affect the development of the hypothalamic-pituitary-adrenal (HPA) axis, and cause cellular and molecular changes in the developing hippocampus that can result in neurobehavioral changes later in life. Epidemiological data implicate stress as a cause of seizures in both children and adults. Emerging evidence indicates that both prenatal and postnatal stress can prime the developing brain for seizures and an increase in epileptogenesis. This article reviews the cellular and molecular changes encountered during prenatal and postnatal stress, and assesses the possible link between these changes and increases in seizure occurrence and epileptogenesis in the developing hippocampus. In addititon, the priming effect of prenatal and postnatal stress for seizures and epileptogenesis is discussed. Finally, the roles of epigenetic modifications in hippocampus and HPA axis programming, early-life stress, and epilepsy are discussed. PMID:24574961

[Early mobilization. Competencies, responsibilities, milestones].

PubMed

Nydahl, P; Dewes, M; Dubb, R; Filipovic, S; Hermes, C; Jüttner, F; Kaltwasser, A; Klarmann, S; Klas, K; Mende, H; Rothaug, O; Schuchhardt, D

2016-03-01

Early mobilization is an evident, interprofessional concept to improve the outcome of intensive care patients. It reduces psychocognitive deficits and delirium and attenuates a general deconditioning, including atrophy of the respiratory pump and skeletal muscles. In this regard the interdisciplinary approach of early mobilization, taking into account different levels of mobilization, appears to be beneficial. The purpose of this study was to explore opinions on collaboration and tasks between different professional groups. During the 25th Bremen Conference on Intensive Medicine and Nursing on 20 February 2015, a questionnaire survey was carried out among the 120 participants of the German Early Mobilization Network meeting. In all, 102 questionnaires were analyzed. Most participants reported on the interdisciplinarity of the approach, but none of the tasks and responsibilities concerning early mobilization can be assigned to a single professional group. The practical implementation of mobilizing orally intubated patients may require two registered nurses as well as a physical therapist. Implementation in daily practice seems to be heterogeneous. There is no consensus regarding collaboration, competencies, and responsibilities with respect to early mobilization of intensive care patients. The approach to date has been characterized by a lack of interprofessional communication, which may lead to an inefficient use of the broad and varied base of knowledge and experienceof the different professions.

Induction of the cellular stress response in Chironomus (Diptera)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pardalis, G.; Hudson, L.A.; Ciborowski, J.J.H.

1995-12-31

The accumulation of stress or heat shock proteins is involved in the protection and defense of a cell from environmentally induced damage. Under stressful conditions, cytoplasmic stress protein 70 migrates to the nucleus where it assists in the restoration of the nucleolar function. The authors have demonstrated a dose-response relationship between incidence of decreased nucleolar size in chironomid salivary glands and degree of sediment contamination. Reduced nucleolar size is indicative of reduced nucleolar function. The relationship between nucleolus size and stress protein accumulation is being explored. They are conducting experiments on chironomids to characterize the response elicited by heat shockmore » and PAH exposure in the laboratory to determine if the simultaneous action of more than one stressor can significantly alter the stress response. Simultaneous studies are being conducted to validate these biomarkers in mesocosm caging experiments. Aspects of the response will be useful as biomarkers of general stress.« less